Hydrocarbon emissions from gas engine
CHP-units 2011 measurement program
Datum
Status
June 2012
Definitive
KEMA
in opdracht van Agentschap NL
Colofon
Projectnaam
Projectnummer
Versienummer
Publicatienummer
Locatie
Projectleider
Contactpersoon
Hydrocarbon emissions from gas engine CHP-units
2011 measurement program
ROBP100154
Utrecht
Michel de Zwart, Agentschap NL
Michel de Zwart, Agentschap NL
Aantal bijlagen
Auteurs
1
G.H.J. van Dijk
Dit rapport is tot
stand gekomen
door:
KEMA in samenwerking met het Ministerie van Infrastructuur
en Milieu, Agentschap NL, Energy Matters en Jacob Klimstra
Consultancy.
Hoewel dit rapport met de grootst mogelijke zorg is samengesteld kan
Agentschap NL geen enkele aansprakelijkheid aanvaarden voor eventuele fouten.
Hydrocarbon emissions from gas engine
CHP-units
2011 measurement program
(Anonymized report)
Groningen, June 28, 2012
74100741-GCS 12-1002 (anonymized report)
Hydrocarbon emissions from gas engine
CHP-units
2011 measurement program
Groningen, June 28, 2012
Author G.H.J. van Dijk
By order of NL Agency, Croeselaan 15, Utrecht
author : G.H.J. van Dijk
reviewed : A. Dijks
B
approved : J. Knijp
141 pages
2 annexes
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74100741-GCS 12-1002
SUMMARY
In December 2009, the Ministry of Infrastructure and Environment (I&M) issued the Decree
on Emission Limits for Middle Sized Combustion Installations (BEMS). This decree imposes
a first-time emission limit value (ELV) of 1500 mg C/m3o at 3% O2 for hydrocarbons emitted
by gas engines. I&M used the findings of two hydrocarbon emission measurement programs,
executed in 2007 and 2009, as a guideline for this initial ELV. The programs did reveal
substantial variation in the hydrocarbon emissions of the gas engines tested. This variation,
and especially the uncertainty as to the role of engine and/or other parameters causing such
variation, was felt to hamper further policy development. I&M therefore commissioned KEMA
to perform follow-up measurements on ten gas engine CHP-units in 2011. Aim of this 2011
program is to assess hydrocarbon emission variation in relation to engine parameters and
process conditions including maintenance status, and to atmospheric conditions. The 2011
program comprised two identical measurement sessions, one in spring and one in winter.
The set of (dark and light) green bars in figure 1 represent the hydrocarbon emissions of the
ten CHP-units as observed in the 2011 spring session. The (dark and light) blue bars give
the hydrocarbon emissions as found in the 2011 winter session. Hydrocarbon emission
levels observed in the 2007 and 2009 programs are given in dark grey respectively light grey.
Hydrocarbon emission in mg C/m 3o @ 3%O2
Overview of hydrocarbon emissions in 2007, 2009 and 2011 measurement programs
2250
2000
1750
2007 -> catalyst-out
2011-spring -> engine-out
2011-winter -> engine-out
* = CHP-unit without catalyst
2009 -> catalyst-out (or engine-out *)
2011-spring -> catalyst-out
2011-winter -> catalyst-out
BEMS ELV
1500
1250
1000
750
500
250
0
CHP-unit
CHP-unit
CHP-unit
CHP-unit
CHP-unit
CHP-unit
CHP-unit
CHP-unit
CHP-unit
CHP-unit
#1
#2
#3 *
#4
#5 *
#6
#7
#8
#9 *
#10
Figure 1 Overview of the hydrocarbon emissions of the ten CHP-units as found in the 2011 program,
including those of the 2007 and 2009 programs (based on measurements with FID analyzers
using propane for span calibration).
Figure 1 reveals that seven of the ten CHP-units tested met the initial BEMS hydrocarbon
ELV target in both of the 2011 measurement sessions. The corresponding as-found engine
parameters and process conditions proved to be in normal state, meaning that other engine
performances, e.g. NOx-emission, were not compromised.
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74100741-GCS 12-1002
CHP-unit #6 met the BEMS hydrocarbon target in the winter session, but only after the
supplier had corrected the maladjusted settings for air-to-fuel ratio and ignition timing found
in the spring session. CHP-unit #5 met the BEMS hydrocarbon target in the spring session,
albeit with NOx-emissions exceeding the current BEES ELV. The supplier of this unit
subsequently readjusted the air-to-fuel ratio to a more fuel-lean setting, but this proved
inadequate as in the winter session hydrocarbon and NOx-emissions still proved slightly
above target. Retarding the ignition timing may help to bring both emissions down, albeit at
an additional cost of efficiency. Ultimately engine design measures, e.g. crevice volume
reduction, could be considered to meet the hydrocarbon target without compromising other
engine performances. CHP-unit #4 exceeded the BEMS hydrocarbon ELV target in both
sessions. This unit's anti-polishing top-end design probably explains for the relatively high
hydrocarbon emissions. Anti-polishing designs aim to reduce top-end wear rates and
typically involve an increase in piston top-land crevice volume. The latter crevice generally is
a main source of hydrocarbon emissions as will be debated below. The hydrocarbon
emissions of the biogas CHP-unit #9 prove surprisingly low. Clarification as to the cause of
this is highly recommended. Effectively, eight of the ten CHP-units tested thus met the BEMS
hydrocarbon ELV target with normal state operating conditions; CHP-units #4 and #5 will
need specific measures to meet this target.
Figure 1 further reveals that for eight of the ten CHP-units tested only a minor difference
between their spring and winter session's hydrocarbon emissions was observed. Although
generally being within hydrocarbon emission measurement uncertainty, in some cases this
difference may also reflect a net effect of minor shifts in engine process conditions. The more
substantial delta between the spring and winter session as observed for CHP-units #5 and
#6 can evidently be attributed to the aforementioned readjustment of engine settings. These
findings emphasize the necessity of insight in engine parameters and process conditions
when analyzing different sets of hydrocarbon emission data from a given engine. Moreover,
they suggest that a difference in engine parameter and process conditions lay at the root of
the substantial spread in hydrocarbon emission levels found for given units between the
2007, 2009 and 2011 programs. Lastly, these findings give evidence of adequate
compensation by the engine management systems for changes in atmospheric conditions.
Suggestion was that the modification from aluminum pistons to steel pistons in CHP-unit #10
explains for this unit's large drop in hydrocarbon emissions between the 2007 and 2009
programs. Notwithstanding the steel pistons, the hydrocarbon slip observed in the 2011
program proved roughly on a par again with the relatively high level found in the 2007
program.
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74100741-GCS 12-1002
Unfortunately, analysis as to the cause of this variation by comparison of the engine
operating condition data was hampered by the lack of such data from the 2007 and 2009
programs. Clarification of the possible sense of steel pistons as an engine-design measure to
reduce hydrocarbon emissions from its suggested effect of allowing a smaller piston top-land
crevice is highly recommended.
Not counting 'odd-design' CHP-unit #4 and biogas CHP-unit #9, the hydrocarbon emissions
of the 2011 program engine population roughly ranged between 1000 and 1500 mg C/m3o at
3% O2. Arguably, this range represents the forefront of modern gas engine technology with
respect to hydrocarbon emission. As such, the lower end of this range could serve as an
ultimate guideline for what is technically feasible in terms of engine-bound measures for
hydrocarbon emission reduction across the entire engine population. Substantial enginebound reduction beyond this lower limit is unlikely given the necessity of having crevices in
the combustion chamber for adequate life-time of critical engine components, and given the
necessity of (ultra-)fuel-lean engine operation for highest power output, efficiency and fuelgas acceptance. Unfortunately, end-of-pipe hydrocarbon abatement using current oxidation
catalysts is not a viable option given the poor effectiveness of such catalysts for methane
and even ethane under typical gas engine operating conditions. The oxidation sections in the
CO2-dosing catalyst systems tested in the 2011 program removed on average just 6% of the
hydrocarbons from the engine exhaust gas. Conversion rate for the methane fraction was
only 1% while that for the non-methane fraction amounted to roughly 36%. Consequently, the
lower end of the aforementioned range could also serve as an ultimate guideline for possible
future tightening of the BEMS hydrocarbon emission limit. Downward steps in the BEMS
hydrocarbon ELV should give ample allowance for the necessary efforts by engine
manufacturers to thoroughly test engine design changes. Such design changes will by
necessity have an incremental character with each step requiring field testing typically in the
order of years prior to release on production engines.
As to the source of hydrocarbon emissions from gas engines, crevices i.e. narrow gaps in the
combustion chamber are known to be the main source. Air-fuel mixture trapped in such
crevices escapes combustion due to quenching of the flame and is subsequently expelled
into the exhaust of the gas engine. The amount of mixture escaping combustion, and hence
an engine's hydrocarbon emission base level, is mainly determined by the size of the
crevices and the in-cylinder conditions during the combustion process.
The piston top-land crevice typically is the largest crevice and serves to protect the
lubrication oil in the top-ring area from overheating. Maintaining proper lubrication conditions
in the top-ring area is essential for engine life-time.
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74100741-GCS 12-1002
Engine manufacturers thus face a delicate balancing act in reducing the size of the piston
top-land crevice and its associated hydrocarbon emissions and fuel-loss, while maintaining
acceptable engine life-time. Hence the earlier appeal for sensible timing of possible future
changes in hydrocarbon emission legislation.
The in-cylinder conditions relevant for hydrocarbon emissions are to some extent governed
by certain engine process conditions. The air-to-fuel ratio of the cylinder charge is one such
condition as e.g. fuel-leaning tends to increase flame-quenching in crevices or near the walls
of the combustion chamber. In too fuel-lean mixtures, even whole pockets of air-fuel mixture
can escape combustion. In the 2011 program, CHP-units #5 and #6 are examples of where
an (intentional) change in the air-to-fuel ratio setting explains for the observed shift in
hydrocarbon emissions. The 2011 findings further illustrate that there is no 'golden' air-to-fuel
ratio with respect to hydrocarbon slip. Different engines (types) will have different sets of
optimum process conditions providing the desired engine performances. CHP-units #6 and
#10 e.g. proved that the high air-to-fuel ratios typical for prechamber gas engines not
necessarily implicate high hydrocarbon emissions. Ignition timing is another process
condition affecting hydrocarbon emissions as this affects the cylinder charge pressure during
the combustion process and consequently the mass of air-fuel mixture trapped in a crevice.
The 2011 program did not provide a clear illustration of the sensitivity of hydrocarbon slip to
ignition timing. Hydrocarbon emission further is sensitive to the intake manifold temperature
as governed by the charge cooler temperature controller. E.g. increasing the intake manifold
temperature leads to higher combustion temperatures which reduces flame-quenching in
crevices or near walls. The stable intake manifold temperatures observed in the 2011
program did not allow illustration of this sensitivity.
Misfire adds to the hydrocarbon emissions as it involves the repeated discharge of unburned
cylinder charges into the exhaust system. Misfire results from malfunctioning ignition systems
and/or overleaning of the air-fuel mixture. The share of misfire-related hydrocarbon slip
depends on the misfire-rate i.e. the frequency with which subsequent cylinder charges fail to
ignite and/or fully combust. In the 2011 program, CHP-units # 3, #5 and #8 were found to be
misfiring, albeit at a very low rate still, thus only contributing little to the units' hydrocarbon
emissions.
Modern CHP-units almost all have sophisticated engine management systems capable of
proper control of the engine process conditions relevant for hydrocarbon emissions. Hence
the earlier remark on the adequate compensation for changes in atmospheric conditions
observed in the 2011 program. More and more engine management systems also include
misfire-detection allowing for early detection and subsequent correction of misfire.
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74100741-GCS 12-1002
Fouling of the combustion chamber could well be an important clue in explaining for the
substantial variation in hydrocarbon emissions for given CHP-units observed between the
2007, 2009 and 2011 programs. Such gradual fouling, mainly carbon deposits from (partially)
burned lubricating oil, could on the one hand reduce hydrocarbon emissions by reducing e.g.
the piston top-land crevice volume. On the other hand could porous deposits in the combustion chamber act as a layer of 'microscopic' crevices effectively increasing crevice volume.
Carbon build up in the combustion chamber will certainly affect engine performances such as
NOx-emissions or sensitivity to knock as a consequence of e.g. the gradual increase in
compression ratio. In turn, such gradual changes in engine performances could lead to
automatic readjustments of engine settings by the engine management system and/or to adhoc manual readjustments by maintenance personnel. Irrespective of its origins, such
readjustments will affect hydrocarbon emissions too. Unfortunately, the 2011 program
maintenance monitoring did not provide conclusive evidence for a correlation between
combustion chamber fouling and hydrocarbon emissions. Clarification of the possible role of
combustion chamber fouling (and cleaning) as a root cause for scatter in subsequent
hydrocarbon emission measurements on given engines is highly recommended.
Based on findings of the 2007 measurement program, I&M uses a factor of 93% to calculate
the methane emissions from the measured hydrocarbon emissions for all gas engine CHPunits. The average methane fraction in the hydrocarbon emissions downstream of the
catalyst systems found in the 2011 program proves marginally lower at c. 91%. A possible
bias in the FID correction method used could well explain for this difference. Care should be
taken when determining the methane fraction in the hydrocarbon emissions from gas
engines without an oxidation catalyst system or from gas engines running on other types of
fuel gas as than a different methane fraction factor would need to apply.
The BEMS decree prescribes the use of the flame ionization detector method according to
standards NEN-EN 12619 (and NEN-EN 13526) for hydrocarbon emission measurements. It
was found that this method overestimates the hydrocarbon emissions, and the methane
emissions and global warming potential derived thereof, for gas engines running on
methane-based fuel gases. The apparent characteristics of the FID analyzer used in the
2011 program suggest an overestimation of the hydrocarbon emissions by over 12%.
Comparative analysis of the separately measured methane and hydrocarbon emissions
confirmed this order of magnitude for the overestimation. Given that there are several options
to improve the accuracy of the hydrocarbon emission measurements, investigation of the
pros and cons of such options is highly recommended.
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1
74100741-GCS 12-1002
CONTENTS
page
SUMMARY ............................................................................................................................... 3 1 CONTENTS ............................................................................................................ 8 2 INTRODUCTION .................................................................................................... 9 3 3.1 3.2 3.3 3.4 3.5 MEASUREMENT PROGRAM .............................................................................. 11 Selected CHP-units .............................................................................................. 11 CHP-unit settings .................................................................................................. 12 Emission testing.................................................................................................... 12 Performance and process conditions testing ........................................................ 15 Maintenance monitoring ....................................................................................... 16 4 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10 MEASUREMENT RESULTS ................................................................................ 18 CHP-unit #1 .......................................................................................................... 18 CHP-unit #2 .......................................................................................................... 20 CHP-unit #3 .......................................................................................................... 22 CHP-unit #4 .......................................................................................................... 24 CHP-unit #5 .......................................................................................................... 25 CHP-unit #6 .......................................................................................................... 27 CHP-unit #7 .......................................................................................................... 29 CHP-unit #8 .......................................................................................................... 31 CHP-unit #9 .......................................................................................................... 32 CHP-unit #10 ........................................................................................................ 34 5 FLAME IONIZATION DETECTOR METHOD ....................................................... 37 6 6.1 6.2 6.3 6.4 6.5 SUMMARY AND DISCUSSION OF MEASUREMENT RESULTS ....................... 40 Hydrocarbon emissions overview ......................................................................... 40 Hydrocarbon emission limit value outlook ............................................................ 42 Engine parameters and process conditions.......................................................... 43 Catalyst hydrocarbon conversion ......................................................................... 46 Hydrocarbon emission methane fraction .............................................................. 48 7 7.1 7.2 CONCLUSIONS AND RECOMMENDATIONS .................................................... 50 Conclusions .......................................................................................................... 50 Recommendations ................................................................................................ 51 Annex A – Tabulated measurement data ............................................................................... 53 Annex B – SGS emission measurement and calculation methods ...................................... 134 -9-
2
74100741-GCS 12-1002
INTRODUCTION
In December 2009, the Ministry of Infrastructure and Environment (I&M) issued the Decree
on Emission Limits for Middle Sized Combustion Installations (BEMS), imposing stringent
emission limit values for combustion equipment. This decree includes a first-time emission
limit value (ELV) for hydrocarbons emitted by gas engines 1 .
I&M used the findings of two hydrocarbon emission measurement programs, executed in
2007 and 2009, as a guideline for the initial ELV of 1500 mg C/m3o at 3% O2.
The first measurement program, in 2007, comprised ten gas engine CHP-units, for which a
population-averaged catalyst-out hydrocarbon emission of c. 1285 mg C/m3o at 3% O2 was
found. In 2009, a second measurement program was executed, comprising thirty gas engine
CHP-units 2 . Here, the population-averaged catalyst-out hydrocarbon emission amounted to
c. 1215 mg C/m3o at 3% O2. In both programs, the variation in hydrocarbon emissions
between CHP-units of different make and type proved substantial. E.g. in 2009, the worstperforming CHP-unit emitted well over 300% more unburned hydrocarbons than the bestperforming CHP-unit. Moreover, for six out of eight CHP-units tested in both programs,
significant differences were found between their 2007 and 2009 hydrocarbon emission
levels. In the most extreme case, this difference amounted to over 100%. This variation, and
especially the uncertainty as to the role of engine and/or other parameters causing such
variation, was felt to be hampering further policy development by I&M.
I&M therefore commissioned KEMA to perform follow-up measurements on ten gas engine
CHP-units in 2011. The aim of this 2011 measurement program is to assess hydrocarbon
emissions variation in relation to engine parameters and process conditions including
maintenance status, and to atmospheric conditions. For this purpose, the 2011 program
includes additional monitoring and measurements related to the emissions and performances
of gas engine CHP-units. Furthermore, the 2011 program is executed twice, in spring 2011
and in winter 2011.
This report presents the findings of the 2011 measurement program. In chapter 4, the main
measurement results for the individual CHP-units are given and explained. Chapter 5 discusses the accuracy of the prescribed flame ionization detector method for gas engine
1
Only applicable to natural-gas-fuelled gas engines with a fuel gas input of 2.5 MW and above. Any
such gas engine installed after April 1st 2010 need to comply with the emission limit value (ELV) for
hydrocarbons directly, whereas for that installed prior to April 1st 2010, compliance to this ELV
becomes compulsory per January 1st 2017. Biogas engines are exempted from this hydrocarbon ELV.
2
The 30-unit population measured in 2009 comprised eight units from the 10-unit population
measured in 2007.
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74100741-GCS 12-1002
hydrocarbon emission measurements. An overall summary and discussion of the hydrocarbon emission findings is presented in chapter 6. The conclusions and recommendations
to be drawn from the 2011 measurement program are presented in chapter 7.
Annex A holds a detailed tabulated overview of all 2011 measurement data, whereas annex
B describes the emission measurement and calculation methods used by SGS
Environmental Services BV.
But first, in chapter 3, a detailed description of the 2011 measurement program is given.
Note 1: Given their installation date prior to April 1st, 2010, all natural-gas-driven CHP-units
under investigation will not be liable for compliance with the BEMS ELVs before
January 1st, 2017. The single biogas CHP-unit is exempted from the BEMS
hydrocarbon ELV all together.
In this report, the initial BEMS hydrocarbon ELV of 1500 mg C/m3o at 3% O2 just
serves as a target level in order to yardstick the hydrocarbon emission of the CHPunits tested.
Note 2: In this report (ref. 74100741-GCS 12-1002), certain references to the identification
of the CHP-units tested are deleted.
Full identification of the CHP-units tested is given in a confidential version of this
report (ref. 74100741-GCS 12-1001).
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3
74100741-GCS 12-1002
MEASUREMENT PROGRAM
The 2011 measurement program involves ten gas engine CHP-units. From these units, a
range of emission and performance parameters is measured in relation to their operating
conditions and maintenance status.
Prior to the start of the 2011 spring measurement sessions, all ten test sites were visited in
the presence of representatives of the supplier and owner of the CHP-units to evaluate the
required on-site preparations. The actual measurements were performed in the presence
and under supervision of a representative of the supplier of the CHP-unit under investigation.
Follow-up on the measurement preparations and commitment to the measurement program
by both the owners and the suppliers was truly excellent.
In section 3.1, the main characteristics of the ten CHP-units selected are given. The engine
set points and process conditions adopted during testing are described in section 3.2.
Section 3.3 describes the set up used for emission testing, followed in section 3.4 by that for
the performance and process condition measurements. Lastly, in section 3.5 a description of
the maintenance status monitoring is given.
3.1
Selected CHP-units
A steering committee 3 , installed and presided by NL Agency, selected the ten gas engine
CHP-units for the 2011 program. This population comprises nine CHP-units from the 2009
measurement program and five CHP-units from the 2007 program.
Nine of the ten selected CHP-units run on natural gas and are installed in horticulture
companies. Of these, seven are equipped with an exhaust gas catalyst system for CO2dosing. The tenth, and smallest, CHP-unit runs on biogas in a swine research farm. This unit
does not have a catalyst system.
All ten CHP-units are grid-connected. The rated electric power outputs range between 360
kW and 5120 kW. Three CHP-units feed into a 10 kV grid and the rest feed into a 400 V grid.
3
The steering committee members are:
- NL Agency
- Ministry of Infrastructure and Environment
- Infomil
- Jacob Klimstra Consultancy
- Energy Matters
- KEMA
- SGS
: M. de Zwart (chairman),
: H. Walthaus,
: W. Burgers,
: J. Klimstra,
: S. Schlatmann and E. Koolwijk,
: G.H.J. van Dijk,
: H.J. Olthuis.
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74100741-GCS 12-1002
The gas engines in eight of the CHP-units have an open chamber combustion system; the
remaining two engines are equipped with prechamber combustion.
All but one engine is running at 1500 rpm; the remaining, and biggest, engine runs at 750
rpm. The latter engine further is equipped with inlet-port-injection of the main fuel gas flow,
whereas in all other engines, the main fuel gas flow is premixed with the combustion air
upstream of the turbocharger.
Further details on the gas engines and catalyst systems can be found in the Gas engine
characteristics and Catalyst characteristics tables in annex A.
3.2
CHP-unit settings
For all but one CHP-unit, the measurements were performed with the engine set for rated
power output, reflecting the 'as found' condition. The power output set point of the remaining
unit was temporarily raised to c. 95% of its rated power, adhering just to its contractual power
export limitation.
Other primary engine settings affecting the engine emissions and performance, such as
ignition timing, air-to-fuel ratio, intake manifold charge temperature and jacket water
temperature, were adopted 'as found'. Of these, all but the jacket water temperature (set
point) were measured and recorded, the latter being regularly checked for stability only,
using the engine management system.
In the 'as found' condition, the routing of the exhaust gas downstream of the catalyst systems
to either greenhouse or chimney is computer-controlled based on CO2-demand from the
greenhouse. Switching between both routings will to some extent affect the exhaust gas
back-pressure. This in turn may affect the engine emissions and performance. When
deemed necessary for an undisturbed measurement, the set point for the exhaust gas
routing was temporarily locked to either green house or chimney. Whenever feasible, the
exhaust gas routing adopted in the 2011 spring session was used in the 2011 winter session
too. The adopted routings can be found in the Emission data tables in annex A.
3.3
Emission testing
For the CHP-units equipped with a catalyst system, an emission test comprised two series of
three consecutive 30-minute measurements. In the first series, the engine-out emissions
were measured, whereas in the second series, the catalyst-out emissions were measured.
In all engine-out measurements, the exhaust gas was sampled upstream from the urea
injector of the catalyst system.
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74100741-GCS 12-1002
In all catalyst-out measurements, the exhaust gas was sampled downstream from the
condensing exhaust gas heat exchanger. Furthermore, in all catalyst-out measurements, the
urea injection was active.
The emission test for the three CHP-units without catalyst system comprised only one series
of three consecutive 30-minute measurements. Evidently, this series concerned the engineout emissions.
In one case here, the exhaust gas was sampled downstream from the condensing exhaust
gas heat exchanger. In another, this was done upstream from the condensing exhaust gas
heat exchanger in order to duplicate the 2009 measurement program conditions. In the case
of the biogas CHP-unit, the sample was taken from the uncooled exhaust gas upstream from
the silencer.
Arrangements were made with the owners of the CHP-units to ascertain that the gas engine
and catalyst system were properly warmed up prior to the start of the tests.
Table 1 gives an overview of the measured exhaust gas emission components and the type
of exhaust gas analysis used.
Table 1 Measured exhaust gas emission components and type of analysis.
Component
Unit
Dry / wet analysis
Formula
-
-
Oxygen
O2
%-v
dry
Carbon monoxide
CO
ppm-v
dry
Carbon dioxide
CO2
%-v
dry
Nitrogen oxide
NO
ppm-v
dry
Nitrogen oxides
NOx (NO + NO2)
ppm-v
dry
CH4
ppm-v
dry
CxHy (as C3H8)
ppm-v
wet
Name
Methane
Hydrocarbons
All emission tests further comprised measurement of the atmospheric conditions i.e.
pressure, temperature and relative humidity, and of the exhaust gas temperature at the
sample location downstream of the condensing exhaust gas heat exchanger.
In addition, prior to the start of the first measurement series, a sample of the fuel gas was
taken. This sample was afterwards analyzed in KEMA's fuel and exhaust gas analysis
laboratory to obtain the composition and properties of the fuel gas.
The data acquisition sample rate for the emission measurements was set at 5 min-1.
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74100741-GCS 12-1002
From the measured emissions, and using the fuel gas properties and atmospheric
conditions, the emissions as per table 2 were calculated.
Table 2 Overview of calculated exhaust gas emissions 4 .
Component
Name
Carbon monoxide
Nitrogen oxide
Nitrogen oxides
Methane
Hydrocarbons
Hydrocarbons
Unit A
(in dry exhaust gas)
Unit B
(in dry exhaust gas)
-
-
Formula
CO
mg/m3o
at 3%-V O2
g/GJ
NO (as NO2)
mg/m3o
at 3%-V O2
g/GJ
NOx (as NO2)
mg/m3o
at 3%-V O2
g/GJ
CH4
mg/m3o
at 3%-V O2
g/GJ
CxHy (as C)
mg/m3o
at 3%-V O2
g/GJ
CxHy (as CH4)
mg/m3o
at 3%-V O2
g/GJ
Furthermore, the dry oxygen fraction corrected for incomplete combustion 5 was calculated,
as was the corresponding air-to-fuel ratio λ.
In addition, the so-called methane slip was derived from the measured methane emission.
This slip represents the energy content of the methane emission expressed as a percentage
of the fuel gas energy input; it serves the purpose of being a simple indicator of the level of
fuel slip loss in a gas engine.
Also, the net global warming potential associated with the observed hydrocarbon emission
was calculated in terms of mass-based CO2-equivalent emission per unit of fuel gas energy.
The measured hydrocarbon emission in wet exhaust gas was converted to same in dry
exhaust gas using the water fraction in the exhaust gas. The latter fraction was not measured
but calculated from the atmospheric conditions, fuel gas composition and combustion
stoichiometry. The water fraction in the exhaust gas downstream from the condensing
exhaust gas heat exchanger was calculated using the measured exhaust gas temperature at
the sample location and assuming full saturation.
The exhaust gas flow was derived from the measured fuel gas flow using the fuel gas
properties and combustion stoichiometry.
For all of the aforementioned measured and calculated parameters, the average values over
the 30-minute measurement intervals can be found in the Emission data tables in annex A.
4
The newly-introduced BEMS ELVs are expressed in unit A, whereas the BEES ELVs are expressed
in unit B. For ease of evaluation, the observed exhaust gas emissions are given in both units.
5
The correction was done for the following incomplete combustion products: NO, NO2, CO and CH4.
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74100741-GCS 12-1002
For the measured emission parameters only, the minimum, maximum and standard deviation
values per 30-minute measurement interval are listed in the Emission data statistics tables in
annex A. Annex A further provides the composition and properties of the fuel gas samples.
3.4
Performance and process conditions testing
The performance tests comprised energy flow measurements, gas engine process condition
measurements and electric power output stability measurements.
Fuel gas consumption was measured using the CHP-unit in-situ gas meter 6 . From the gas
meter electronic volume converter, gas volume readings were recorded at the start and end
of each series of three consecutive 30-minute emission measurements. These readings
represent the gas volume at reference conditions. The elapsed time between the two
readings was accurately recorded using a stopwatch. Fuel gas consumption divided by time
gives the average fuel gas flow over the c. 90 minute measurement period.
The corresponding average fuel gas input in terms of power was calculated using the lower
heating value resulting from the aforementioned fuel gas analysis.
Gross electricity production was measured using the CHP-unit in-situ gross electric energy
meter 7 . This meter records electricity energy production based on accurate voltage and
current measurements on the gross electric output of the generator. Here too, meter
readings at the start and end of each series of three consecutive 30-minute emission
measurements were recorded. The elapsed time between the two readings was determined
using a stopwatch again. Gross electricity production divided by time gives the average gross
electric power output over the c. 90 minute measurement period.
The CHP-unit LHV-based average electric efficiency over the c. 90-minute measurement
period was calculated from dividing gross electric power output by fuel gas input.
The energy flow and efficiency data can be found in the Measured energy flows and electric
efficiency tables in annex A.
In parallel with the emission and energy flow measurements, some key gas engine process
conditions were recorded. The combustion air temperature was measured in the air flow
directly upstream from the air filter using a PT100 temperature sensor.
6
The in-situ gas meters typically are used for fuel gas consumption monitoring purposes only i.e. not
for billing purposes.
7
These in-situ electric energy meters are specifically installed and used by the electricity network
companies for accurate registration of the gross electricity production.
-16-
74100741-GCS 12-1002
In case the engine was equipped with two air filters, and when deemed necessary for a
representative measurement, the combustion air temperature at both air filters was
monitored.
Using a K-type thermocouple temperature sensor, the exhaust gas temperature directly
downstream from the turbocharger was measured. In case the engine was equipped with two
turbochargers, both downstream exhaust gas temperatures were monitored.
The intake manifold charge pressure and temperature conditions were measured using
piezoresistive pressure transducers and PT100 temperature sensors. In case the engine was
equipped with separate intercoolers for left- and right-hand cylinder banks, the intake
manifold charge temperature in both banks was measured. Also, when separate throttle
valves for left- and right-hand banks were present, the intake manifold charge pressure in
both banks was recorded.
The data sample rate for the engine process condition measurements was set at 20 min-1.
All gas engine process condition data can be found in the Measured gas engine process
conditions tables in annex A.
In parallel with the aforementioned performance tests, the stability of the electric power
output was monitored, using a unique KEMA measurement set-up.
This stability is a measure of running speed variations which are a telltale for combustion
stability, and thereby for hydrocarbon emissions resulting from (imminent) overleaning of the
combustible mixture and misfiring.
The measurement system determines the top-top variation and RMS variation of the
generator gross electric power output in a series of 2-minute intervals over the entire test
period. Data post-processing takes c. 1 minute per 2-minute interval. Each 90-minute test
periods therefore comprise a series of thirty power stability measurements.
The observed power stability can be found in the Measured gross electric power output
variation graphs in annex A 8 .
3.5
Maintenance monitoring
Maintenance work on a gas engine CHP-unit can seriously affect its hydrocarbon emission.
Spark plug regapping or renewal can for example eliminate misfire-related hydrocarbon
emission. Another example is adjustment of the air-to-fuel ratio set point, typically done for
NOx-emission adjustment, but affecting the hydrocarbon emission too. Cleaning deposits
from pistons and cylinder liners is known to have an impact on the top land crevice volume
related hydrocarbon emissions.
8
Note: the top-top and RMS variations are expressed as a percentage of the gross electric power
output.
-17-
74100741-GCS 12-1002
But also less typical maintenance work such as installing latest-design engine parts, e.g.
pistons, can affect the hydrocarbon emission. Therefore, the maintenance status must be
considered when evaluating the hydrocarbon emission between different measurements for
a given CHP-unit.
For this reason, great effort was put in identifying relevant maintenance work being
performed in the period between the 2011 spring and winter sessions. Furthermore, in some
cases information on maintenance work was retrieved for the period(s) between the 2007,
2009 and 2011 measurement sessions.
The actual maintenance monitoring in the measurement sessions itself comprised recording
of the actual CHP-unit total running hours. In addition, the total running hours at the time of
the previous and of the planned next regular maintenance 9 events were recorded. From this
data, the 'timing' of the measurement sessions within the regular maintenance and overhaul
scheme can be derived. This timing can be of interest for evaluation of e.g. misfire in relation
to spark plug wear or crevice volume related hydrocarbon emission in relation to top land
area cleaning during overhaul work.
The engine run time data can be found in the Gas engine characteristics tables in annex A.
Whenever possible, also catalyst run time data was recorded. This can be found in the
Catalyst system characteristics tables in annex A.
Both tables further list any known atypical or irregular maintenance event with a possible
effect on the hydrocarbon emission.
Any adjustment of relevant engine settings in the period between the 2011 spring and winter
session can be found in different tables in annex A, e.g. the ignition timing in the Gas engine
characteristics table or the air-to-fuel ratio in the Emission data table.
Any known key events in the maintenance history of the CHP-units in the 2007 to 2011
timeframe are listed in the summary tables in the next chapter.
9
Here, regular maintenance events refer to those maintenance intervals that involve work with
possible relevance for the hydrocarbon emissions only. Such work e.g. typically includes spark plug
regapping or renewal, air filter renewal, valve gap resetting and adjustment of engine settings.
-18-
4
74100741-GCS 12-1002
MEASUREMENT RESULTS
In sections 4.1 to 4.10, the key results of the 2011 measurement program are presented per
individual CHP-unit 10 .
4.1
CHP-unit #1
This CHP-unit is driven by a 16-cylinder gas engine in Vee-configuration. It is equipped with
a catalyst system for CO2-dosing purposes.
This unit's rated electric power output is 1558 kW and engine speed is 1500 rpm. The engine
has a compression ratio of 12:1 and features an open chamber combustion system. The
specific engine load in terms of brake mean effective pressure (BMEP) amounts to c. 18.3
bar. This CHP-unit was commissioned in June 2006 and participated in the 2007 and 2009
measurement programs.
Table 3 gives an overview of the key results of the 2011 measurement program. For purpose
of comparison, the corresponding results of the 2007 and 2009 programs are listed too.
The actual electric power output of the CHP-unit roughly matched rated power output in both
sessions. The electric efficiency ranged between 41.4 and 41.5%.
In terms of engine process conditions, the c. 0.01-point difference in air-to-fuel ratio and 1
o
CA difference in ignition timing between both sessions stand out. The c. 8 oC drop in
exhaust gas temperature in the winter session is a consequence of this shift in ignition timing
and the slightly lower intake manifold temperature.
The winter session's colder weather is seen reflected in the lower combustion air
temperature and possibly in the aforementioned intake manifold temperature decrease.
Combustion stability proved excellent as indicated by the low variation in electric power
output. The maintenance monitoring did not suggest any relevance for the hydrocarbon slip
of this CHP-unit.
The hydrocarbon emission itself proved comfortably below the BEMS ELV of 1500 mg C/m3o
at 3% O2 in both sessions, as it did in the 2007 and 2009 programs.
The winter session's hydrocarbon slip was a minor 5% above that of the spring session. This
delta is well within the measurement uncertainty 11 of the hydrocarbon emission
measurement. Possibly though, this delta reflects some net effect of the aforementioned
changes in air-to-fuel ratio and ignition timing.
10
11
For a full listing of the measurement data per individual CHP-unit, see annex A.
See table B2 in annex B for an overview of the emission measurement uncertainties.
-19-
74100741-GCS 12-1002
Table 3 Overview of the 2011 (and 2009/2007) key measurement results.
CHP-unit #1
Test period
2011 - spring
2009 1), 3)
2007 2), 3)
2011- winter
Engine_out Catalyst_out Engine_out Catalyst_out Catalyst_out Catalyst_out
Emissions
Cx Hy as C 4)
mg/m3o @ 3 %-v O2
1066
1001
1018
961
969
823
mg/m3o @ 3 %-v O2
1421
1335
1357
1282
1291
1097
CH4 5)
mg/m3o @ 3 %-v O2
1087
1069
1068
1053
---
---
NOx (as NO2)
mg/m3o @ 3 %-v O2
838
29
845
25
---
28
%-v (dry)
9.32
9.30
9.27
9.33
9.23
9.19
kW
% (LHV-based)
% (of actual power)
% (of actual power)
1554.3
41.4
6.1 to 7.8
0.8 to 1.1
1554.9
41.5
5.8 to 7.8
0.8 to 0.9
1558.7
41.4
5.7 to 7.2
0.8 to 0.9
1558.6
41.5
5.9 to 7.7
0.8 to 0.9
1500
35.2
-----
1521
42.7
-----
Cx Hy as CH4
4)
O2 (as measured)
Electric power output
Electric power
Electric efficiency
Variation (top_top)
Variation (RMS)
Process conditions
Ignition timing
Air-to-fuel ratio (λ)
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Atmospheric conditions
Pressure
Temperature
Relative humidity
Absolute humidity
Maintenance remarks
o
BTDC
o
C
bara
o
C
o
C
1.71
14.3
3.29
46.6
427
1.71
12.8
3.29
47.3
---
1.70
20.2
3.30
49.9
434
1.71
20.4
3.29
48.3
435
-------------
-------------
mbar
o
C
%
g H2O/kg dry air
1002
7
86
5.4
1003
6
84
4.9
1027
20
52
7.4
1028
15
69
7.2
999
12
91
8.0
1017
24
43
7.9
c. 26
c. 25
· Gas engine (apr 2011-nov 2011) : only typical (ir-)regular maintenance inbetw een the 2011 sessions.
· Catalyst (may 2010-nov 2011)
Notes:
: only typical (ir-)regular maintenance just prior to and inbetw een the 2011 sessions.
1) Measurement results taken from reports 50964183-TOS/TCM 09-6715 rev. 1 and 50964183-TOS/TCM 09-6714.
2) Measurement results taken from reports 50762926-TOS/TCM 07-7080 and 50761926-TOS/TCM 07-7081.
3) The electric power output and electric efficiency as reported from the 2007 and 2009 programs seem a bit off-scale,
presumably due to the indicative nature of the measurement procedure being used at that time.
4) As calculated from measurements with FID analyzers using propane for span calibration.
5) As calculated from measurements with a methane analyzer.
The catalyst-out hydrocarbon emissions proved roughly 6% lower than the corresponding
engine-out hydrocarbon emissions. This moderate reduction over the catalyst system is
typical for the majority of the catalyst systems in use for CO2-dosing purposes. It can be
attributed to the oxidation of primarily non-methane hydrocarbons in the oxidation catalyst
section of such catalyst systems.
In comparison with the 2011 and 2009 catalyst-out hydrocarbon emission levels, the c. 15%
lower level observed in 2007 stands out. This delta goes beyond measurement uncertainties
and should involve additional causes. Unfortunately, the lack of detailed engine process
condition data from the 2007 and 2009 programs prohibits any conclusive analysis, other
than a possible effect of the apparently lower air-to-fuel ratio in 2007.
-20-
4.2
74100741-GCS 12-1002
CHP-unit #2
This CHP-unit was commissioned in December 2006. It is driven by a 16-cylinder gas engine
in Vee-configuration and uses a catalyst system for CO2-dosing purposes.
The rated electric power output is 1562 kW and specific engine load (BMEP) amounts to c.
17.1 bar. The 1500 rpm engine has a compression ratio of 12:1 and deploys an open
chamber combustion system.
This CHP-unit was included in the 2007 and 2009 measurement programs.
Table 4 gives an overview of the key results of the 2011 measurement program. For purpose
of comparison, the corresponding 2007 and 2009 results are listed too.
Table 4 Overview of the 2011 (and 2009/2007) key measurement results.
CHP-unit #2
Test period
2011- winter
2011 - spring
2009 1), 3)
2007 2), 3)
Engine_out Catalyst_out Engine_out Catalyst_out Catalyst_out Catalyst_out
Emissions
Cx Hy as C 4)
mg/m3o @ 3 %-v O2
1224
1128
1264
1208
1170
1450
mg/m3o @ 3 %-v O2
1632
1504
1685
1610
1558
1934
CH4 5)
mg/m3o @ 3 %-v O2
1277
1262
1335
1296
---
---
NOx (as NO2)
mg/m3o @ 3 %-v O2
744
48
497
45
---
36
%-v (dry)
9.25
9.24
9.40
9.34
9.35
9.33
kW
% (LHV-based)
% (of actual power)
% (of actual power)
1553.8
40.4
6.0 to 8.4
0.9 to 1.0
1553.5
40.4
6.2 to 9.0
0.8 to 1.0
1549.8
40.0
6.8 to 10.2
0.9 to 1.5
1548.5
40.0
7.2 to 9.3
1.0 to 1.3
1566
42.3
-----
1562
43.1
-----
Cx Hy as CH4
4)
O2 (as measured)
Electric power output
Electric power
Electric efficiency
Variation (top_top)
Variation (RMS)
Process conditions
Ignition timing
Air-to-fuel ratio (λ)
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Atmospheric conditions
Pressure
Temperature
Relative humidity
Absolute humidity
Maintenance remarks
o
BTDC
o
C
bara
o
C
o
C
1.69
14.3
3.04
47.0
464
1.69
14.5
3.04
47.0
464
1.71
22.1
3.15
46.9
477
1.71
24.3
3.15
47.0
479
-------------
-------------
mbar
o
C
%
g H2O/kg dry air
1013
9
76
5.4
1011
10
70
5.3
1026
17
54
6.4
1024
19
49
6.6
1003
18
55
7.1
1006
17
85
10.3
22
c. 20
· Gas engine (oral communication) : just prior to 2011 w inter session cyl. heads & pistons cleaning to prevent continuous knock-induced ignition timing adjustment as observed in 2011 spring session; otherw ise only typical (ir-)regular maintenance inbetw een the 2011 sessions.
· Catalyst (oral communication)
Notes:
: only typical (ir-)regular maintenance inbetw een the 2011 sessions.
1) Measurement results taken from reports 50964183-TOS/TCM 09-6715 rev. 1 and 50964183-TOS/TCM 09-6714.
2) Measurement results taken from reports 50762926-TOS/TCM 07-7080 and 50761926-TOS/TCM 07-7081.
3) The electric power output and electric efficiency as reported from the 2007 and 2009 programs seem a bit offscale, presumably due to the indicative nature of the measurement procedure being used at that time.
4) As calculated from measurements with FID analyzers using propane for span calibration.
5) As calculated from measurements with a methane analyzer.
-21-
74100741-GCS 12-1002
The actual electric power output proved within fair range of the rated power output in both
sessions. The corresponding electric efficiency was 40.0% respectively 40.4%.
In terms of engine process conditions, the differences in air-to-fuel ratio and ignition timing
stand out. In both sessions, the ignition timing set point was 22 oBTDC. The ignition timing in
the spring session however varied between c. 19.5 and 20.5 oBTDC as a result of continuous
adjustment by the knock protection system, whereas that of the winter's session proved
stable at 22 oBTDC 12 . In addition, the air-to-fuel ratio proved c. 0.02-point apart between
both sessions. The significance of both deltas can be seen from the roughly 50% rise in
engine-out NOx-emission between the spring and winter session. A net effect is also seen in
the c. 14 oC drop in exhaust gas temperature.
The winter session's colder weather is reflected in the lower combustion air temperature. The
latter's associated higher air density could be responsible for the aforementioned shift in airto-fuel ratio.
The relatively high level of variation in electric power output in the spring session reflected
this session's instable ignition timing. The stable ignition timing in the winter session did
improve combustion stability, although the base level remains relatively unfavorable.
Maintenance monitoring did not suggest any relevance for the hydrocarbon slip for this CHPunit either.
The hydrocarbon emission again proved comfortably below the BEMS ELV of 1500 mg
C/m3o at 3% O2 in both sessions, as it did in the 2009 program. The 2007 hydrocarbon
emission was only marginally below the BEMS ELV.
The winter session's engine-out hydrocarbon slip proved a minor 3% below that of the spring
session. This delta is well within the measurement uncertainty 13 of the hydrocarbon
emission measurement. Again though, this delta may reflect some net result of the (opposite)
effects of the aforementioned changes in air-to-fuel ratio and ignition timing.
Further noteworthy is the apparent doubling of the catalyst hydrocarbon conversion rate from
roughly 4% to 8% between the spring and winter session. The catalyst operating conditions
i.e. exhaust gas temperature and space velocity, nor the catalyst's maintenance history
support such a boost in hydrocarbon oxidation activity. Moreover, the CH4 conversion rate
instead declined between the spring and winter session, leaving just emission measurement
uncertainty as a plausible explanation.
12
13
The ignition timing adjustment issue was solved by cleaning of the combustion chambers.
See table B2 in annex B for an overview of the emission measurement uncertainties.
-22-
74100741-GCS 12-1002
In comparison with the 2011 and 2009 catalyst-out hydrocarbon emission levels, the c. 25%
higher level observed in 2007 stands out. This delta goes beyond measurement uncertainties
and should involve additional causes. Unfortunately, the lack of detailed engine process
condition data from the 2007 and 2009 programs prohibits any conclusive analysis.
4.3
CHP-unit #3
This CHP-unit is driven by a 20-cylinder gas engine in Vee-configuration and was commissioned in March 2007. There is no catalyst system installed.
This unit's rated electric power output is 1064 kW and specific engine load (BMEP) is c. 18.2
bar. The engine has a compression ratio of 12.5:1 and uses an open chamber combustion
system. Engine speed is 1500 rpm.
This CHP-unit participated in the 2009 measurement program too.
Table 5 gives an overview of the key results of the 2011 measurement program. For purpose
of comparison, the 2009 results are listed also.
The actual electric power output exactly matched rated power in both sessions. For the
electric efficiency, 38.5% respectively 38.8% was found.
No significant differences in engine process conditions other than a minor 0.01-point shift in
air-to-fuel ratio and some 6 oC delta in the combustion air temperature were apparent
between both sessions. The latter delta evidently reflects the colder winter weather.
The power output variation measurement clearly indicated misfire in both sessions as can be
seen from the high peak levels for the top-top variation of the electric power output. Given
the very mild misfire-rate, significance of this misfire for the hydrocarbon emission is probably
low.
Maintenance monitoring showed that two (but most probably three) cylinders had the
combustion chamber cleaned in between both sessions.
Here too, the hydrocarbon emission proved comfortably below the BEMS ELV of 1500 mg
C/m3o at 3% O2 in both sessions, as it did in the 2009 program.
In contrast to what could be expected from the minor drop in air-to-fuel ratio, the winter
session's hydrocarbon emission was c. 10% higher than that observed in the spring session.
Most likely, measurement uncertainty 14 will explain for the larger share of this effect.
Possibly, the combustion chamber maintenance plays a role too, provided that the cleaning
of the combustion chambers has opened up crevices.
14
See table B2 in annex B for an overview of the emission measurement uncertainties.
-23-
74100741-GCS 12-1002
Table 5 Overview of the 2011 (and 2009) key measurement results.
CHP-unit #3
Test period
2011- winter
2011 - spring
2009 1), 2)
Engine_out Catalyst_out Engine_out Catalyst_out Engine_out
Emissions
Cx Hy as C 3)
2007
Engine_out
mg/m3o @ 3 %-v O2
1167
n/a
1059
n/a
946
---
mg/m3o @ 3 %-v O2
1556
n/a
1412
n/a
1260
---
CH4 4)
mg/m3o @ 3 %-v O2
1170
n/a
1100
n/a
---
---
NOx (as NO2)
mg/m3o @ 3 %-v O2
554
n/a
686
n/a
773
---
%-v (dry)
9.18
n/a
9.23
n/a
9.06
---
n/a
n/a
n/a
n/a
1064.1
38.8
5.9 to 24.4
0.8 to 1.0
n/a
n/a
n/a
n/a
1049
39.0
-----
---------
Cx Hy as CH4
3)
O2 (as measured)
Electric power output
Electric power
Electric efficiency
Variation (top_top)
Variation (RMS)
Process conditions
Ignition timing
Air-to-fuel ratio (λ)
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Atmospheric conditions
Pressure
Temperature
Relative humidity
Absolute humidity
Maintenance remarks
kW
1062.9
% (LHV-based)
38.5
% (of actual power) 6.6 to 25.1
% (of actual power) 1.0 to 1.2
o
BTDC
o
C
bara
o
C
o
C
20
1.68
14.6
3.38
47.2
452
n/a
n/a
n/a
n/a
n/a
n/a
20
1.69
20.5
3.34
44.6
451
n/a
n/a
n/a
n/a
n/a
n/a
-------------
-------------
mbar
o
C
%
g H2O/kg dry air
1018
10
93
7.1
n/a
n/a
n/a
n/a
1023
19
31
4.2
n/a
n/a
n/a
n/a
1019
17
54
6.5
---------
· Gas engine (mar 2007-dec 2011) : in betw een the 2011 sessions cleaning of multiple combustion chambers; otherw ise only typical (ir-)regular maintenance
in betw een the 2011 sessions; occasional misfire during both 2011 sessions.
· Catalyst
Notes:
: n/a
1) Measurement results taken from reports 50964183-TOS/TCM 09-6715 rev. 1 and 50964183-TOS/TCM 09-6714.
2) The electric power output (and probably also the electric efficiency) as reported from the 2009 program seem a bit
off-scale, presumably due to the indicative nature of the measurement procedure being used at that time.
3) As calculated from measurements with FID analyzers using propane for span calibration.
4) As calculated from measurements with a methane analyzer.
Equally surprising is the apparent c. 20% drop in NOx-emission between the spring and
winter session. Here too, one would expect a minor opposite effect from the marginal
differences in engine process conditions. In addition to measurement uncertainty, the higher
absolute humidity in the winter session can explain for part of this reversed effect. Water
vapor in the combustion air is known to decrease the NOx-emission from its high specific
heat, effectively reducing combustion peak temperatures and thereby reducing thermal NOxformation.
The 2009 hydrocarbon emission is somewhat below that of the 2011 program. Apart from
measurement uncertainty, the apparent less fuel-lean engine operation in 2009 could explain
for part of this difference. Unfortunately, no adequate 2009 engine process condition data is
available to support conclusive analysis as to the cause of this delta in hydrocarbon emission
-24-
4.4
74100741-GCS 12-1002
CHP-unit #4
This CHP-unit, driven by a 20-cylinder gas engine in Vee-configuration, was commissioned
in April 2009. For CO2-dosing purposes a catalyst system is installed.
Electric power rating is 1200 kW and specific engine load (BMEP) amounts to c. 19.3 bar.
The 1500 rpm engine has an open chamber combustion system with a compression ratio of
11.9:1.
On request of the supplier, this CHP-unit was entered in the 2011 program as it would better
reflect the latest design status over the older CHP-units participating in the 2009 and 2007
programs.
Table 6 gives an overview of the key results of the 2011 measurement program.
Table 6 Overview of the 2011 key measurement results.
CHP-unit #4
Test period
2011- winter
2011 - spring
2009
2007
Engine_out Catalyst_out Engine_out Catalyst_out Catalyst_out Catalyst_out
Emissions
Cx Hy as C 1)
mg/m3o @ 3 %-v O2
2039
1891
1844
1811
---
---
Cx Hy as CH4 1)
mg/m3o @ 3 %-v O2
2719
2521
2459
2414
---
---
CH4 2)
mg/m3o @ 3 %-v O2
2120
2094
1969
1955
---
---
NOx (as NO2)
mg/m3o
O2 (as measured)
Electric power output
Electric power
Electric efficiency
Variation (top_top)
Variation (RMS)
Process conditions
Ignition timing
Air-to-fuel ratio (λ)
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Atmospheric conditions
Pressure
Temperature
Relative humidity
Absolute humidity
Maintenance remarks
@ 3 %-v O2
614
38
648
15
---
---
%-v (dry)
9.20
9.19
9.17
9.10
---
---
kW
% (LHV-based)
% (of actual power)
% (of actual power)
1215.8
40.8
5.8 to 7.8
0.8 to 0.9
1215.8
40.9
5.5 to 10.7
0.8 to 1.0
1210.2
41.0
6.2 to 7.7
0.9 to 1.0
1209.7
40.9
6.2 to 8.1
0.9 to 1.0
---------
---------
o
BTDC
o
C
bara
o
C
o
C
1.66
30.7
3.79
45.1
440
1.67
31.3
3.81
46.7
440
1.66
26.0
3.79
48.9
444
1.66
25.5
3.79
48.8
444
-------------
-------------
mbar
o
C
%
g H2O/kg dry air
1016
7
94
5.8
1016
7
95
5.9
1017
23
36
6.2
1017
23
36
6.2
---------
---------
c. 25
c. 25
· Gas engine (oral communication) : in dec 2010 equipped w ith anti-polishing liners & pistons w ith unknow n effect on crevice volume; only typical (ir-)regular
maintenance in betw een 2011 sessions; tw o misfire-events in 2011 w inter catalyst-out session.
· Catalyst
Notes:
: no data available.
1) As calculated from measurements with an FID analyzer using propane for span calibration.
2) As calculated from measurements with a methane analyzer.
The actual electric power output marginally exceeded the power output rating in both
sessions. The corresponding electric efficiency proved in the c. 40.9% region.
-25-
74100741-GCS 12-1002
Other than a negligible 0.01-point rise in air-to-fuel ratio and a minor drop in intake manifold
and exhaust gas temperature, no significant change in engine process conditions was seen
between the spring and winter session. Remarkable though is the roughly 5 oC higher
combustion air temperature in the winter session, attributable to the control algorithm used in
this unit's cabinet ventilation system.
The electric power output variation measurement indicated stable combustion, albeit at a
somewhat unfavorably high base level.
The maintenance monitoring did not suggest any relevance for the hydrocarbon slip of this
CHP-unit.
Notwithstanding its apparent recent design status, the hydrocarbon emission of this CHP-unit
proved unfavorably high and exceeds the BEMS ELV of 1500 mg C/m3o at 3% O2.
From communication with the supplier of this CHP-unit, it transpired that in December 2010
special anti-polishing pistons and cylinder liners were installed as a measure to reduce topend wear. The supplier was unaware of the precise effect of this design change on the piston
top-land crevice. Generally though, anti-polishing top-end designs involve an increase in topend crevice volume. Since this crevice is the main source of hydrocarbon slip, this unit's antipolishing top-end hardware most likely explains for the relatively high hydrocarbon emission
observed.
Some 11% rise in engine-out hydrocarbon emission was observed between the spring and
winter session. Given the stable engine process conditions, apart from measurement
uncertainty, no further clue can be given to explain this difference.
Further noteworthy is the corresponding only 4% rise in catalyst-out hydrocarbon emission.
This would suggest a triplication of the catalyst activity for hydrocarbon conversion between
the spring and winter session. There is no obvious ground for such a boost in hydrocarbon
conversion, leaving just measurement uncertainty as a plausible explanation.
4.5
CHP-unit #5
A 16-cylinder gas engine in Vee-configuration is the prime mover in this 1400 kW CHP-unit.
It was commissioned in December 2008 and has no catalyst system.
The engine has a compression ratio of 12.7:1 and deploys an open chamber combustion
system. Engine speed is 1500 rpm and specific engine load (BMEP) amounts to c. 19.3 bar.
This CHP-unit was measured before in the 2009 program.
Table 7 gives an overview of the key results of the 2011 measurement program. For purpose
of comparison, the 2009 results are listed too.
-26-
74100741-GCS 12-1002
Table 7 Overview of the 2011 (and 2009) key measurement results.
CHP-unit #5
Test period
2011- winter
2011 - spring
2009 1), 2)
Engine_out Catalyst_out Engine_out Catalyst_out Engine_out
Emissions
Cx Hy as C 3)
2007
Engine_out
mg/m3o @ 3 %-v O2
1515
n/a
987
n/a
1017
---
mg/m3o @ 3 %-v O2
2020
n/a
1316
n/a
1355
---
CH4 4)
mg/m3o @ 3 %-v O2
1508
n/a
1105
n/a
---
---
NOx (as NO2)
mg/m3o @ 3 %-v O2
842
n/a
2077
n/a
1649
---
%-v (dry)
9.41
n/a
8.77
n/a
8.65
---
n/a
n/a
n/a
n/a
1402.5
41.6
4.5 to 28.8
0.6 to 0.9
n/a
n/a
n/a
n/a
1431
44.5
-----
---------
Cx Hy as CH4
3)
O2 (as measured)
Electric power output
Electric power
Electric efficiency
Variation (top_top)
Variation (RMS)
Process conditions
Ignition timing
Air-to-fuel ratio (λ)
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Atmospheric conditions
Pressure
Temperature
Relative humidity
Absolute humidity
Maintenance remarks
kW
1397.2
% (LHV-based)
40.5
% (of actual power) 7.7 to 28.9
% (of actual power) 1.0 to 1.4
o
BTDC
o
C
bara
o
C
o
C
c. 20
1.71
11.0
3.65
43.1
440
n/a
n/a
n/a
n/a
n/a
n/a
c. 20
1.63
25.4
3.46
42.6
451
n/a
n/a
n/a
n/a
n/a
n/a
-------------
-------------
mbar
o
C
%
g H2O/kg dry air
1021
10
91
6.9
n/a
n/a
n/a
n/a
1018
23
29
5.0
n/a
n/a
n/a
n/a
1023
17
56
6.7
---------
· Gas engine (dec 2008-dec 2011) : in betw een 2009 and 2011 spring sessions only typical (ir-)regular maintenance; in betw een 2011 sessions only typical
(ir-)regular maintenance; occasional misfire during 2011 spring session, repeated misfire during 2011 w inter session.
· Catalyst
Notes:
: n/a.
1) Measurement results taken from reports 50964183-TOS/TCM 09-6715 rev. 1 and 50964183-TOS/TCM 09-6714.
2) The electric power output and electric efficiency as reported from the 2009 program seem a bit off-scale,
presumably due to the indicative nature of the measurement procedure being used at that time.
3) As calculated from measurements with FID analyzers using propane for span calibration.
4) As calculated from measurements with a methane analyzer.
In both sessions, the observed electric power output was close to the rated power output.
Nonetheless, the corresponding electric efficiency proved to differ by c. 1.1%-point.
This delta is easily explained from the 0.08-point increase in air-to-fuel ratio between the
spring and winter session. Following the spring session, the supplier of the CHP-unit had
changed the air-to-fuel ratio setting to bring the NOx-emission down by some 60% in an effort
to meet the current BEES ELV for NOx. The more fuel-lean air-fuel mixture is also seen reflected in the winter session's higher intake manifold pressure and lower exhaust gas temperature. The colder winter weather is apparent in the lower combustion air temperature only.
In both sessions, ignition timing varied around a nominal value of 20 oBTDC as a result of
continuous adjustment by the knock protection system.
The high peak levels for the top-top variation of the electric power output clearly gave
evidence of misfire in both sessions. Given the relatively low misfire-rate in both sessions,
-27-
74100741-GCS 12-1002
significance of this misfire for the hydrocarbon emission is probably low.
Maintenance monitoring showed no relevance for the hydrocarbon slip of this CHP-unit.
The hydrocarbon emission was greatly affected by the readjustment of the air-to-fuel ratio.
The winter session hydrocarbon emission marginally exceeded the BEMS ELV, whereas that
of the spring session was still comfortably below this ELV. The roughly 50% rise in
hydrocarbon emission follows from the typical sensitivity of hydrocarbon emission to air-tofuel ratio.
Possibly, the winter session's more fuel-lean operation contributed to the somewhat higher
misfire rate in this session.
The 2009 apparent lower air-to-fuel ratio does not support the c. 3% higher hydrocarbon
emission and 20% lower NOx-emission as compared to the 2011 spring session. Again, the
lack of further data on the 2009 engine process conditions prohibits any conclusive analysis.
4.6
CHP-unit #6
CHP-unit #6 is driven by a 12-cylinder gas engine in Vee-configuration and was
commissioned in August 2006. It is equipped with a catalyst system for CO2-dosing
purposes.
The electric power output rating for this CHP-unit is 5120 kW and specific engine load
(BMEP) is c. 18.5 bar. The 750 rpm engine has a prechamber combustion system and uses
inlet port injection for the main fuel gas flow. Its compression ratio is 13:1.
This CHP-unit also participated in the 2007 and 2009 programs.
Table 8 gives an overview of the key findings of the 2011 measurement program. For
purpose of comparison, the 2007 and 2009 findings are listed also.
The actual electric power output proved within fair range of the rated power output in both
sessions. The corresponding electric efficiency was seen to have risen from 44.2 to 45.3%
between both sessions.
In terms of engine process conditions, the differences in air-to-fuel ratio and ignition timing
stand out. A drop of some 0.07-point in air-to-fuel ratio was seen between the spring and
winter session, while the nominal ignition timing 15 had advanced from 10.8 to 12.3 oBTDC.
The supplier of the CHP-unit related that both adjustments were done to win electric efficiency by using the potential associated with the spring session's low engine-out NOx emission.
15
Individual cylinders had a fixed off-set to this nominal timing, ranging from -0.75 oCA to +0.75 oCA.
-28-
74100741-GCS 12-1002
Table 8 Overview of the 2011 (and 2009/2007) key measurement findings.
CHP-unit #6
Test period
2011- winter
2011 - spring
2009 1), 3)
2007 2), 3)
Engine_out Catalyst_out Engine_out Catalyst_out Catalyst_out Catalyst_out
Emissions
Cx Hy as C 4)
mg/m3o @ 3 %-v O2
1321
1321
1651
1638
1763
1110
mg/m3o @ 3 %-v O2
1761
1762
2201
2184
2349
1480
CH4 5)
mg/m3o @ 3 %-v O2
1371
1370
1787
1794
---
---
NOx (as NO2)
mg/m3o @ 3 %-v O2
661
52
205
68
69
61
%-v (dry)
10.66
10.62
11.13
11.11
10.55
10.77
5232
45.5
-----
5147
46.6
-----
Cx Hy as CH4
4)
O2 (as measured)
Electric power output
Electric power
Electric efficiency
Variation (top_top)
Variation (RMS)
Process conditions
Ignition timing
Air-to-fuel ratio (λ)
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Atmospheric conditions
Pressure
Temperature
Relative humidity
Absolute humidity
Maintenance remarks
kW
5135.8
% (LHV-based)
45.3
% (of actual power) 8.6 to 10.3
% (of actual power) 1.3 to 1.5
o
5136.0
5145.0
5145.3
45.3
44.2
44.1
8.3 to 10.7 12.8 to 51.0 13.2 to 17.0
1.3 to 1.5
1.8 to 2.3
2.0 to 2.3
BTDC
o
C
bara
o
C
o
C
1.91
32.9
3.47
50.8
404
1.91
33.2
3.47
50.2
404
1.98
32.1
3.75
51.4
386
1.98
32.1
3.77
51.6
384
-------------
-------------
mbar
o
C
%
g H2O/kg dry air
1008
8
71
4.7
1010
8
77
5.1
1025
16
58
6.5
1024
15
64
6.7
1021
16
43
4.8
1003
17
98
12.0
c. 12.3
c. 10.8
· Gas engine (mid 2007-dec 2011) : prior to 2007 session & mid 2010 & just prior to 2011 w inter session cyl. heads w ere replaced; just prior to 2011 w inter
session readjustment of ign. timing and λ; prior to 2011 spring session 'test' spark plugs w ere installed; one single misfire
event in 2011 spring session; further just typical (ir-)regular maintenance.
· Catalyst (sep 2006-dec 2011)
Notes:
: March 2009 catalyst system w as cleaned.
1) Measurement findings taken from reports 50964183-TOS/TCM 09-6715 rev. 1 and 50964183-TOS/TCM 09-6714.
2) Measurement findings taken from reports 50762926-TOS/TCM 07-7080 and 50761926-TOS/TCM 07-7081.
3) The electric power output and electric efficiency as reported from the 2007 and 2009 programs may be somewhat
off-scale, due to the indicative nature of the measurement procedure being used at that time.
4) As calculated from measurements with FID analyzers using propane for span calibration.
5) As calculated from measurements with a methane analyzer.
This readjustment proved successful given the aforementioned significant efficiency gain
between both sessions. The engine-out NOx-emission rose by over 200%, yet still being
compliant with the current BEES NOx ELV. A net effect is also seen in the c. 19 oC increase
in exhaust gas temperature.
The winter session's colder weather did not affect the combustion air temperature nor the
intake manifold temperature.
Noteworthy is the relatively high base level for the electric power output variation in the
spring session. This gives evidence to instable combustion, probably as a consequence of
the relatively unfavorable engine settings in terms of air-to-fuel ratio and ignition timing.
Just prior to the winter session, all cylinder heads had been replaced. This will most probably
-29-
74100741-GCS 12-1002
not have affected top-land crevice-related hydrocarbon emission as no piston or cylinder liner
cleaning was involved.
The aforementioned readjustments, and especially that of the air-to-fuel ratio, proved
beneficial for the hydrocarbon slip too. The new setting(s) saw the hydrocarbon emission
drop below the BEMS ELV target.
Noteworthy further is the apparent low catalyst hydrocarbon oxidation rate. This is
presumably due to this unit's low exhaust gas temperature being typical for large-bore ultralean-burn gas engines.
The 2007 and 2009 catalyst-out hydrocarbon emissions seemingly show an atypical trend
given their apparent air-to-fuel ratios. Again, the lack of further engine process condition data
from the 2009 and 2007 programs hampers a conclusive analysis.
4.7
CHP-unit #7
This CHP-unit, driven by a 12-cylinder gas engine in Vee-configuration, was commissioned
in November 2005. A catalyst system for CO2-dosing purposes is installed.
Rated power output is 1166 kW, engine speed is 1500 rpm and specific engine load (BMEP)
amounts to c. 18.3 bar. The engine has a compression ratio of 13.5:1 and is equipped with
an open chamber combustion system. This unit before participated in the 2009 program.
Table 9 gives an overview of the key findings of the 2011 measurement program. For
purpose of comparison, the 2009 findings are listed too.
The actual power output virtually matched the power rating in both sessions. The
corresponding electric efficiency amounted to roughly 41.2% 16 respectively 41.5%.
Apart from a minor 0.01-point increase in air-to-fuel ratio and some 7 oC drop in combustion
air temperature, no significant change in engine process conditions was seen between the
spring and winter session. The latter temperature change reflected the colder winter weather.
Combustion stability proved excellent as indicated by the favorably low variation in electric
power output, except for an odd, single misfire-event in the winter session.
The maintenance monitoring did not suggest any relevance for the hydrocarbon slip.
16
On this location, a single fuel gas meter is used for two CHP-units. In the winter session, the green
house heat demand requirement commanded simultaneous running of both CHP-units. Permission
was given to shutdown the second CHP-unit for the duration of one measurement period only, i.e. the
catalyst-out measurement period.
-30-
74100741-GCS 12-1002
Table 9 Overview of the 2011 (and 2009) key measurement findings.
CHP-unit #7
Test period
2011- winter
2011 - spring
2009 1), 2)
2007
Engine_out Catalyst_out Engine_out Catalyst_out Catalyst_out Catalyst_out
Emissions
Cx Hy as C 3)
mg/m3o @ 3 %-v O2
1195
1124
1196
1084
778
-
mg/m3o @ 3 %-v O2
1593
1498
1595
1445
1037
-
CH4 4)
mg/m3o @ 3 %-v O2
1205
1203
1181
1162
n/a
-
NOx (as NO2)
mg/m3o @ 3 %-v O2
769
24
703
25
21
-
%-v (dry)
9.48
9.44
9.39
9.35
8.98
-
1169.4
41.2
5.4 to 7.3
0.7 to 0.8
1170.5
41.6
5.9 to 7.6
0.8 to 1.1
1170.4
41.4
5.7 to 7.4
0.8 to 0.9
1173
41.8
n/a
n/a
-
Cx Hy as CH4
3)
O2 (as measured)
Electric power output
Electric power
Electric efficiency
Variation (top_top)
Variation (RMS)
Process conditions
Ignition timing
Air-to-fuel ratio (λ)
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Atmospheric conditions
Pressure
Temperature
Relative humidity
Absolute humidity
Maintenance remarks
kW
1169.4
% (LHV-based)
n/a
% (of actual power) 5.2 to 30.9
% (of actual power) 0.8 to 1.0
o
BTDC
o
C
bara
o
C
o
C
1.72
15.7
3.31
46.6
439
1.72
14.7
3.31
46.4
439
1.71
21.3
3.27
46.0
440
1.71
22.8
3.26
45.6
440
n/a
n/a
n/a
n/a
n/a
n/a
-
mbar
o
C
%
g H2O/kg dry air
1016
5
73
3.9
1015
4
77
3.9
1018
17
72
8.6
1017
19
63
8.6
1020
18
45
5.7
-
25
25
· Gas engine (nov 2005-dec 2011) : all cyl. heads and liners replaced & pistons cleaned in betw een 2009 and 2011 spring session; just prior to 2011 spring &
w inter sessions one cylinder-unit w as replaced; further only typical (ir-)regular maintenance in betw een 2011 sessions;
single misfire event during 2011 w inter session.
· Catalyst (okt 2006-aug 2010)
Notes:
: only typical (ir-)regular maintenance.
1) Measurement findings taken from reports 50964183-TOS/TCM 09-6715 rev. 1 and 50964183-TOS/TCM 09-6714.
2) The electric power output and electric efficiency as reported from the 2009 program may be somewhat off-scale,
due to the indicative nature of the measurement procedure being used at that time.
3) As calculated from measurements with FID analyzers using propane for span calibration.
4) As calculated from measurements with a methane analyzer.
Uniquely, this unit's spring and winter engine-out hydrocarbon emission proved equal, being
comfortably below the BEMS ELV of 1500 mg C/m3o at 3% O2. A possible expected minor
effect of the change in air-to-fuel ratio could well have been masked by measurement
uncertainty effects 17 .
Measurement uncertainty will most probably also account for the apparent drop in catalyst
hydrocarbon conversion rate between the spring and winter session.
The apparent 2009 lower air-to-fuel ratio may well explain for the corresponding 30% lower
hydrocarbon emission level as compared to that in the 2011 program. Yet again, no
adequate engine process condition data from the 2009 program is available to substantiate
this presumption.
17
See table B2 in annex B for an overview of the emission measurement uncertainties.
-31-
4.8
74100741-GCS 12-1002
CHP-unit #8
This CHP-unit, driven by an 18-cylinder gas engine in Vee-configuration, was commissioned
in November 2006 and is equipped with a catalyst system for CO2-dosing purposes.
This unit is rated at 2000 kW electric power output, corresponding to a specific engine load
(BMEP) of c. 18.2 bar. The 1500 rpm engine has a compression ratio of 12.5:1 and is
equipped with an open chamber combustion system.
This CHP-unit was included in the 2007 and 2009 programs.
Table 10 gives an overview of the key findings of the 2011 measurement program. For
purpose of comparison, the 2007 and 2009 findings are listed also.
Table 10 Overview of the 2011 (and 2009/2007) key measurement findings.
CHP-unit #8
Test period
2011- winter
2011 - spring
2009 1), 3)
2007 2), 3)
Engine_out Catalyst_out Engine_out Catalyst_out Catalyst_out Catalyst_out
Emissions
Cx Hy as C 4)
mg/m3o @ 3 %-v O2
1391
1375
1318
1215
1255
1129
mg/m3o @ 3 %-v O2
1855
1834
1758
1620
1672
1506
CH4 5)
mg/m3o @ 3 %-v O2
1472
1461
1341
1325
---
---
NOx (as NO2)
mg/m3o @ 3 %-v O2
647
46
634
39
43
51
%-v (dry)
9.21
9.18
9.06
9.00
9.11
8.97
1895.5
39.0
9.1 to 12.0
1.3 to 1.4
1947
35.4
-----
1998
42.6
-----
Cx Hy as CH4
4)
O2 (as measured)
Electric power output
Electric power
Electric efficiency
Variation (top_top)
Variation (RMS)
Process conditions
Ignition timing
Air-to-fuel ratio (λ)
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Atmospheric conditions
Pressure
Temperature
Relative humidity
Absolute humidity
Maintenance remarks
kW
1895.1
1896.1
1896.0
% (LHV-based)
39.3
39.3
39.0
% (of actual power) 11.0 to 24.9 10.1 to 23.6 9.4 to 12.6
% (of actual power) 1.5 to 1.7
1.4 to 1.7
1.3 to 1.5
o
BTDC
o
C
bara
o
C
o
C
1.68
18.5
3.19
48.9
468
1.68
18.1
3.20
49.1
467
1.66
20.5
3.15
50.4
480
1.66
19.8
3.15
50.6
480
-------------
-------------
mbar
o
C
%
g H2O/kg dry air
1020
11
67
5.4
1021
11
67
5.4
1020
12
47
4.0
1020
13
43
3.9
999
11
89
7.4
1008
22
57
9.4
c. 21
c. 20
· Gas engine (dec 2010-dec 2011) : three cil. heads and liners replaced & pistons cleaned prior to 2011 w inter session; further only typical (ir-)regular
maintenance in betw een 2011 sessions; frequent misfire during 2011 w inter session.
· Catalyst (feb 2011-dec 2011)
Notes:
: prior to 2011 spring session oxi-cat cleaning + extra row ; only typical (ir-)regular maintenance inbetw een 2011 sessions.
1) Measurement findings taken from reports 50964183-TOS/TCM 09-6715 rev. 1 and 50964183-TOS/TCM 09-6714.
2) Measurement findings taken from reports 50762926-TOS/TCM 07-7080 and 50761926-TOS/TCM 07-7081.
3) The electric power output and electric efficiency as reported from the 2007 and 2009 programs seem a bit offscale, presumably due to the indicative nature of the measurement procedure being used at that time.
4) As calculated from measurements with FID analyzers using propane for span calibration.
5) As calculated from measurements with a methane analyzer.
-32-
74100741-GCS 12-1002
Due to contractual power export restrictions, the set point for the electric power output could
not be raised beyond 1915 kW. The actual electric power output proved in fair range of the
latter setting in both sessions. The observed electric efficiency amounted to 39.0%
respectively 39.3%.
Some differences in air-to-fuel ratio and ignition timing further stand out. An increase of 0.02point in air-to-fuel ratio was found between the spring and winter session. The actual ignition
timing in both sessions varied on a per-cylinder base as a result of continuous adjustment by
the knock protection system. Effectively, some 1 oCA advance in ignition timing was found
between both sessions.
The combined effect of the aforementioned changes is reflected in the c. 12 oC drop in
exhaust gas temperature and the minor rise in intake manifold pressure.
Noteworthy is further that misfire was observed in the winter session, as is reflected in this
session's high peak levels for the electric power output top-top variation. In general, the
combustion stability base level is unfavorable, most likely due to the unstable ignition timing.
Maintenance monitoring showed that three cylinder heads and liners were replaced, and
pistons cleaned, in between both sessions.
The hydrocarbon emission of this CHP-unit proved comfortably below the BEMS ELV of
1500 mg C/m3o at 3% O2 in both sessions, as it did in the 2007 and 2009 programs. The
winter session's hydrocarbon slip was some 6% above that of the spring session. This delta
is well within the measurement uncertainty 18 of the hydrocarbon emission measurement.
More probably though, this delta reflects a net effect of the aforementioned changes in air-tofuel ratio and ignition timing.
Measurement uncertainty will most probably account for the apparent drop in catalyst
hydrocarbon conversion rate between the spring and winter session.
Judging from the apparent air-to-fuel ratios, the 2007 and 2009 hydrocarbon emission levels
seem more or less consistent with those of the 2011 program. As mentioned before, the lack
of detailed engine process condition data from the 2007 and 2009 programs prohibits further
conclusive analysis.
4.9
CHP-unit #9
CHP-unit #9 is driven by a 12-cylinder gas engine in Vee-configuration and was
commissioned in April 2009. This 360 kW unit is fuelled by biogas and does not have a
catalyst system.
18
See table B2 in annex B for an overview of the emission measurement uncertainties.
-33-
74100741-GCS 12-1002
The engine has a compression ratio of 12:1 and uses an open chamber combustion system.
Engine speed is 1500 rpm and specific engine load (BMEP) is c. 13.7 bar.
This CHP-unit also participated in the 2009 program.
Table 11 gives an overview of the key findings of the 2011 measurement program. For
purpose of comparison, the 2009 findings are listed too.
Table 11 Overview of the 2011 (and 2009) key measurement findings.
CHP-unit #9
Test period
2011- winter
2011 - spring
2009 1), 2)
Engine_out Catalyst_out Engine_out Catalyst_out Engine_out
Emissions
Cx Hy as C 3)
2007
Engine_out
mg/m3o @ 3 %-v O2
292
---
295
---
190
---
mg/m3o @ 3 %-v O2
389
---
393
---
253
---
CH4 4)
mg/m3o @ 3 %-v O2
331
---
314
---
---
---
NOx (as NO2)
mg/m3o @ 3 %-v O2
702
---
655
---
686
---
%-v (dry)
6.76
---
6.50
---
5.86
---
---------
360.1
n/a
44.2 to 75.3
2.4 to 3.4
---------
328
-------
---------
Cx Hy as CH4
3)
O2 (as measured)
Electric power output
Electric power
Electric efficiency
Variation (top_top)
Variation (RMS)
Process conditions
Ignition timing
Air-to-fuel ratio (λ)
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Atmospheric conditions
Pressure
Temperature
Relative humidity
Absolute humidity
Maintenance remarks
kW
n/a
% (LHV-based)
n/a
% (of actual power) 43.8 to 77.6
% (of actual power) 2.0 to 2.8
o
BTDC
o
C
bara
o
C
o
C
18.0
1.46
8.4
2.28
60.2
496
-------------
18.0
1.43
24.2
2.25
57.2
501
-------------
-------------
-------------
mbar
o
C
%
g H2O/kg dry air
1000
5
78
4.3
---------
1023
17
31
3.7
---------
1018
18
65
8.3
---------
· Gas engine (n/a )
: Severe misfire during 2011 spring and w inter sessions.
· Catalyst
: n/a.
Notes:
1) Measurement findings taken from reports 50964183-TOS/TCM 09-6715 rev. 1 and 50964183-TOS/TCM 09-6714.
2) The electric power output as reported from the 2009 program seems a bit off-scale, presumably due to the indicative nature of the measurement procedure being used at that time.
3) As calculated from measurements with FID analyzers using propane for span calibration.
4) As calculated from measurements with a methane analyzer.
The spring session's electric power output exactly matched the power rating of this CHP-unit.
In the winter session, the CHP-unit control system commanded a power derate in the last
minute of the 90-minute measurement period. Although no exact power output could be
determined, the readings from the power analyzer used in the power output stability measurement confirmed the power output to be 360 kW again. Evidently, the winter session's
findings presented represent the performances of this CHP-unit prior to the power derate.
-34-
74100741-GCS 12-1002
The electric efficiency could not be determined since there was no gas meter in the fuel gas
supply to this CHP-unit.
First noteworthy change in the engine process conditions is the c. 0.03-point rise in air-to-fuel
ratio between the spring and winter session. The resulting more fuel-lean operation is seen
reflected in the higher intake manifold pressure and lower exhaust gas temperature.
Unexpectedly, the NOx-emission increased rather than decreased.
The combustion air temperature more or less followed the ambient air temperature as this
containerized CHP-unit was by necessity tested with open doors.
Severe misfire was observed during both sessions, as can be seen from the high peak levels
for the electric power output top-top variation. In general, combustion stability was rather
unfavorable as reflected in the high base levels for the electric power output variations.
The spring and winter session's hydrocarbon emission level proved roughly equal. The
expected effect of the change in air-to-fuel ratio could well have been masked by
measurement uncertainty 19 and differences in hydrocarbon slip originating from different
misfire-rates.
The 2009 hydrocarbon emission is roughly two-third of that observed in the 2011 program.
Given the 2009 apparent lower air-to-fuel ratio, such a lower hydrocarbon emission level
would seem appropriate. However, a definite analysis would require further information on
the 2009 engine process conditions.
4.10
CHP-unit #10
The prime mover in this CHP-unit is a 20-cylinder gas engine in Vee-configuration. The unit
was commissioned in July 2006 and is equipped with a catalyst system for CO2-dosing
purposes.
The electric power output rating for this CHP-unit is 3041 kW and specific engine load
(BMEP) amounts to c. 20.3 bar. The engine has a compression ratio of 12:1 and is equipped
with a prechamber combustion system. Engine speed is 1500 rpm.
This CHP-unit also participated in the 2007 and 2009 programs.
Table 12 gives an overview of the key findings of the 2011 measurement program. For
purpose of comparison, the 2009 and 2007 findings are listed too.
19
See table B2 in annex B for an overview of the emission measurement uncertainties.
-35-
74100741-GCS 12-1002
Table 12 Overview of the 2011 (and 2009/2007) key measurement findings.
CHP-unit #10
Test period
2011- winter
2011 - spring
2009 1), 3)
2007 2), 3)
Engine_out Catalyst_out Engine_out Catalyst_out Catalyst_out Catalyst_out
Emissions
Cx Hy as C 4)
mg/m3o @ 3 %-v O2
1283
1127
1194
1106
605
1238
mg/m3o @ 3 %-v O2
1711
1503
1592
1474
806
1651
CH4 5)
mg/m3o @ 3 %-v O2
1372
1339
1289
1274
---
---
NOx (as NO2)
mg/m3o @ 3 %-v O2
597
63
658
55
58
47
%-v (dry)
10.64
10.60
10.56
10.53
10.25
10.32
kW
% (LHV-based)
% (of actual power)
% (of actual power)
3019.2
42.1
3.3 to 4.0
0.5 to 0.5
3019.0
42.3
3.3 to 4.5
0.4 to 0.5
3021.7
42.4
3.7 to 4.5
0.5 to 0.6
3021.3
42.4
3.4 to 4.4
0.5 to 0.6
3070
44.0
-----
3043
42.6
-----
Cx Hy as CH4
4)
O2 (as measured)
Electric power output
Electric power
Electric efficiency
Variation (top_top)
Variation (RMS)
Process conditions
Ignition timing
Air-to-fuel ratio (λ)
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Atmospheric conditions
Pressure
Temperature
Relative humidity
Absolute humidity
Maintenance remarks
o
BTDC
o
C
bara
o
C
o
C
1.91
15.6
3.89
44.6
406
1.90
16.2
3.89
44.6
406
1.90
18.6
3.83
44.3
409
1.89
19.4
3.83
44.3
409
-------------
-------------
mbar
o
C
%
g H2O/kg dry air
1021
6
89
5.1
1021
7
91
5.6
1025
15
48
5.0
1026
16
48
5.3
1016
17
48
5.7
1008
17
56
6.8
c. 23
c. 23
· Gas engine (apr 2011-nov 2011) : steel pistons and improved prechambers installed in betw een 2009 and 2007 session; turbochargers and tw o cylinder
heads replaced prior to 2011 spring session; just typical (ir-)regular maintenance in betw een 2011 sessions.
· Catalyst (verbal communication)
Notes:
: extra oxi-cat row installed in betw een 2011 and 2009 sessions, otherw ise just typical (ir-)regular maintenance.
1) Measurement findings taken from reports 50964183-TOS/TCM 09-6715 rev. 1 and 50964183-TOS/TCM 09-6714.
2) Measurement findings taken from reports 50762926-TOS/TCM 07-7080 and 50761926-TOS/TCM 07-7081.
3) The electric power output and electric efficiency as reported from the 2007 and 2009 programs seem a bit offscale, presumably due to the indicative nature of the measurement procedure being used at that time.
4) As calculated from measurements with FID analyzers using propane for span calibration.
5) As calculated from measurements with a methane analyzer.
In both sessions, the actual power output proved well within range of the rated power output.
The corresponding electric efficiency amounted to c. 42.4% respectively 42.2%.
In terms of engine process conditions, only the c. 0.01-point rise in air-to-fuel ratio between
the spring and winter session stands out. A reflection of this rise is seen in the exhaust gas
temperature, and probably in electric efficiency too. The increase in intake manifold pressure
is a combined result of the change in air-to-fuel ratio and electric efficiency.
In both sessions, individual cylinders occasionally had their ignition timing retarded by up to 2
o
CA as a result of continuous adjustment by the knock protection system.
Despite the varying ignition timing, combustion stability proved excellent as indicated by the
favorably low variation in electric power output.
The maintenance monitoring did not show any issue with relevance for the hydrocarbon slip.
-36-
74100741-GCS 12-1002
The hydrocarbon emission itself proved comfortably below the BEMS ELV of 1500 mg C/m3o
at 3% O2 in both sessions.
Given the typical sensitivity of hydrocarbon emission to air-to-fuel ratio, the winter session's
slightly higher air-to-fuel ratio may account for some of this session's c. 7% higher engine-out
hydrocarbon emission, in addition to measurement uncertainty 20 .
The former correlation is supported by the simultaneous drop in engine-out NOx-emission.
Measurement uncertainty will most probably also explain for the apparent boost in catalyst
oxidation activity between both sessions.
On comparing the hydrocarbon emission levels observed in the 2007, 2009 and 2011
programs, substantial changes between these levels become evident. Suggestions were that
the roughly 50% drop in hydrocarbon slip from the 2007 to 2009 measurement was
attributable to a modification from aluminum pistons to low-crevice steel pistons just prior to
the 2009 program. The supplier of this CHP-unit could not confirm the suggested low-crevice
design of the steel pistons, other than that the aim of the modification was improvement of
the engine efficiency. Off course, reduction of hydrocarbon slip is an adequate measure to
improve engine efficiency. Notwithstanding the steel pistons were still installed, the
hydrocarbon emission level roughly doubled again from the 2009 to 2011 measurement.
Given the lack of confirmed information on the design of the steel pistons and of detailed
engine process conditions from the 2007 and 2009 programs, no conclusive explanation for
the substantial variation in hydrocarbon levels between the three programs can be given.
20
See table B2 in annex B for an overview of the emission measurement uncertainties.
-37-
5
74100741-GCS 12-1002
FLAME IONIZATION DETECTOR METHOD
The BEMS decree refers to standard NEN-EN 12619 21 as the prescribed measurement
method for hydrocarbon emissions from gas engines. This method involves the use of a
flame ionization detector analyzer (FID analyzer), while propane (C3H8) is to be used for span
calibration of the FID-analyzer.
NEN-EN 12619 acknowledges that FID-analyzers can have different response factors for the
individual components in the hydrocarbon matrix present in the exhaust gas under
investigation. This means that the measurement result of an FID-analyzer by definition
reflects some level of under- or overestimation for hydrocarbons other than the hydrocarbon
used for span calibration.
The competent authorities in the Netherlands consider NEN-EN 13526 22 equivalent to the
aforementioned NEN-EN 12619 standard. Indeed, many emission testing institutions in the
Netherlands hold an accreditation for hydrocarbon emission measurements based on NENEN 13526 instead of NEN-EN 12619.
NEN-EN 13526 too acknowledges that FID-analyzers can have different response factors for
the individual components in the hydrocarbon matrix under investigation. It further lists some
(average) response factors as published for different FID-analyzers.
Table 13 shows those response factors as well as the response factors of the FID-analyzer
used in the 2011 measurement program. The latter response factors are taken from the User
Manual of this FID-analyzer.
It is evident from the response factors in table 13 that an overestimation of the hydrocarbon
emission occurs if the main constituent of the hydrocarbon matrix under investigation is
methane. Research by DNV KEMA and others has revealed that the hydrocarbon fractions in
the fuel gas are a good estimate for the hydrocarbon fractions in the engine-out exhaust gas.
Since methane is the dominant hydrocarbon in most natural gas and biogas fuels, this
means that methane is the main constituent of the hydrocarbons in the corresponding
exhaust gas too. Consequently, FID analyzers will typically overestimate the hydrocarbon
emissions from engines running on typical natural gas and biogas fuels.
21
NEN-EN 12619: Stationary source emissions – Determination of the mass concentration of total
gaseous organic carbon at low concentrations in flue gases – Continuous flame ionization detector
method.
22
NEN-EN 13526: Stationary source emissions – Determination of the mass concentration of total
gaseous organic carbon in flue gases from solvent using processes – Continuous flame ionization
detector method.
-38-
74100741-GCS 12-1002
Table 13 Typical FID response factors as listed in NEN-EN 13526 and response factors of the
Ratfisch RS-200 FID-analyzer as used in the 2011 measurement program.
Hydrocarbon component
Typical FID response factors
(NEN-EN 13526)
- Number of FID
- Average
- Minimum
- Maximum
Ratfisch RS-200 response
factors (+/- 5%)
Methane
(CH4)
Ethane
(C2H6)
Propane
(C3H8)
n-Butane
(n-C4H10)
n-Hexane
(n-C7H16)
8
1.11
1.02
1.26
2
1.01
1.00
1.02
8
1.01
1.00
1.03
6
1.00
0.98
1.02
6
0.98
0.85
1.22
1.12
-
1.00
1.01
1.04
I&M used the findings of the 2007 and 2009 measurement programs as a guideline for the
initial BEMS hydrocarbon ELV. Since FID-analyzers were used in these programs, and
assuming typical response factors for these analyzers, the initial BEMS hydrocarbon ELV
should account for this overestimation effect. The overestimation effect will however still be
reflected in the methane emissions and the global warming potential derived from the FIDmeasured hydrocarbon emissions.
The apparent response factors of the FID analyzer used in the 2011 program suggest an
overestimation of the hydrocarbon emission by at least 12%. This suggestion is supported by
the findings, presented in figure 2, of a comparative analysis of the separately measured
engine-out methane and hydrocarbon emissions of the ten CHP-units under investigation.
The horizontal axis in figure 2 represents the expected hydrocarbon emissions as calculated
from the methane emissions measured with the methane analyzer. This calculation is based
on the assumption that the hydrocarbon component matrix in the exhaust gas is an exact
copy of that in the fuel gas. The vertical axis represents the actual FID-measured
hydrocarbon emissions.
Figure 2 clearly indicates a systematic overestimation in the FID-measured hydrocarbon
emissions as compared to the expected hydrocarbon emissions. The apparent overestimation ranges between c. 7% and 22%. This range scatter can be attributed to
measurement uncertainty 23 in the methane and hydrocarbon emission measurements, and
to differences between the fuel gas and exhaust gas hydrocarbon component matrices.
23
See table B2 in annex B for an overview of the emission measurement uncertainties.
-39-
74100741-GCS 12-1002
FID analyzer: Analysis of 2011 engine-out hydrocarbon emission overestimation
2250
2011 spring session
FID-measured hydrocarbon emission
(mg C/m3o @ 3%O 2)
2000
2011 winter session
1750
1500
Apparent overestimation
range: +7% to +22%
1250
1000
750
500
Line of 0% overestimation
250
0
0
250
500
750
1000
1250
1500
1750
2000
2250
Calculated expected hydrocarbon emission based on measured
CH4-emission and fuel gas composition (mg C/m3o @ 3%O 2)
Figure 2 Analysis of 2011 FID-measured engine-out hydrocarbon emission overestimation.
The accuracy of the flame ionization detector method for measuring the hydrocarbon
emissions from gas engines can easily be improved by using methane instead of propane for
span calibration of the FID-analyzer 24 . Alternatively, correction of the FID measurement
results for the actual response factors could be considered 25 . This option is apparently being
discussed in the expert group working on the revision of the NEN-EN 12619 standard.
Alternatively, other measuring methods e.g. methane analyzers could be used.
24
NEN-EN 12619 and NEN-EN 13526 prescribe propane for span calibration of the FID analyzer.
This will require clear arrangements on the assumptions to be made concerning the hydrocarbon
component matrix in the exhaust gas under investigation. Furthermore, thought should be given on
implementation of the revised NEN-EN 12619 standard by emission testing institutions holding an
accreditation for hydrocarbon emission measurements based on NEN-EN 13526 instead of NEN-EN
12619.
25
-40-
74100741-GCS 12-1002
6
SUMMARY AND DISCUSSION OF MEASUREMENT RESULTS
6.1
Hydrocarbon emissions overview
The set of (dark and light) green bars in figure 3 represent the hydrocarbon emissions of the
ten CHP-units as observed in the 2011 spring session. The (dark and light) blue bars give
the hydrocarbon emissions as found in the 2011 winter session. Hydrocarbon emission
levels observed in the 2007 and 2009 programs are given in dark grey respectively light grey.
The corresponding numerical values are presented in table 14 at the end of this section.
Hydrocarbon emission in mg C/m 3o @ 3%O2
Overview of hydrocarbon emissions in 2007, 2009 and 2011 measurement programs
2250
2000
1750
2007 -> catalyst-out
2011-spring -> engine-out
2011-winter -> engine-out
* = CHP-unit without catalyst
2009 -> catalyst-out (or engine-out *)
2011-spring -> catalyst-out
2011-winter -> catalyst-out
BEMS ELV
1500
1250
1000
750
500
250
0
CHP-unit
CHP-unit
CHP-unit
CHP-unit
CHP-unit
CHP-unit
CHP-unit
CHP-unit
CHP-unit
CHP-unit
#1
#2
#3 *
#4
#5 *
#6
#7
#8
#9 *
#10
Figure 3 Overview of the hydrocarbon emissions of the ten CHP-units as found in the 2011 program,
including those of the 2007 and 2009 programs (based on measurements with FID analyzers
using propane for span calibration).
Figure 3 reveals that seven of the ten CHP-units tested met the initial BEMS hydrocarbon
ELV target in both of the 2011 measurement sessions. The corresponding as-found engine
parameters and process conditions proved to be in normal state, meaning that other engine
performances, e.g. NOx-emission, were not compromised. CHP-unit #6 met the BEMS
hydrocarbon target in the winter session, but only after the supplier had corrected the maladjusted settings for air-to-fuel ratio and ignition timing found in the spring session. CHP-unit
#5 met the BEMS hydrocarbon target in the spring session, albeit with NOx-emissions
exceeding the current BEES ELV. The supplier of this unit subsequently readjusted the airto-fuel ratio to a more fuel-lean setting, but this proved inadequate as in the winter session
hydrocarbon and NOx-emissions still proved slightly above target. The new air-to-fuel ratio
setting had further taken a toll on the electric efficiency and power output stability. Retarding
the ignition timing may help to bring both emissions down, albeit at an additional cost of
efficiency. Ultimately engine design measures, e.g. crevice volume reduction, could be considered to meet the hydrocarbon target without compromising other engine performances.
-41-
74100741-GCS 12-1002
CHP-unit #4 exceeded the BEMS hydrocarbon ELV target in both sessions. In the 2007 and
2009 programs, three out of five engines of the same make and type-range were also seen
to have hydrocarbon emissions above the BEMS target. The supplier entered the newergeneration #4 CHP-unit into the 2011 program as it would reflect the latest design status of
this engine type-range. It transpired though that this engine was equipped with a special antipolishing top-end design and this probably explains for the relatively high hydrocarbon
emissions. Anti-polishing designs aim to reduce top-end wear rates and typically involve an
increase in piston top-land crevice volume. The latter crevice generally is a main source of
hydrocarbon emissions as will be debated below. Hydrocarbon emissions of the biogas CHPunit #9 prove surprisingly low, while no evident explanation is available. Clarification as to the
cause of this is highly recommended.
Effectively, eight of the ten CHP-units tested thus met the BEMS hydrocarbon ELV target
with normal state operating conditions; two CHP-units (#4 and #5) will need specific
measures to meet this target.
Figure 3 further reveals that for eight of the ten CHP-units tested only a minor difference
between their spring and winter session's hydrocarbon emissions was observed. Although
generally being within hydrocarbon emission measurement uncertainty, in some cases this
difference may also reflect a net effect of minor shifts in engine process conditions. The more
substantial delta between the spring and winter session as observed for CHP-units #5 and
#6 can evidently be attributed to the aforementioned readjustment of engine settings. These
findings emphasize the necessity of insight in engine parameters and process conditions
when analyzing different sets of hydrocarbon emission data from a given engine. Moreover,
they suggest that a difference in engine parameter and process conditions lay at the root of
the substantial spread in hydrocarbon emission levels found for given units over the 2007,
2009 and 2011 programs. Lastly, these findings give evidence of adequate compensation by
the engine management systems for changes in atmospheric conditions.
-42-
74100741-GCS 12-1002
Table 14 Numerical overview of the hydrocarbon emissions of the ten CHP-units as found in the
2011 program, including those of the 2007 and 2009 programs (based on measurements
with FID analyzers using propane for span calibration).
Hydrocarbon emissions in mg C/m3o at 3% O2
2007
2009
Catalyst-out
Catalyst-out
Engine-out
Catalyst-out
Engine-out
Catalyst-out
#1
823
969
1018
961
1066
1001
#2
CHP-unit
2011 spring session
2011 winter session
1450
1170
1263
1208
1224
1128
#3 1)
-
946 2)
1059
-
1167
-
#4
-
-
1844
1811
2039
1891
#5 1)
-
1017 2)
987
-
1515
-
1110
1763
1650
1638
1321
1321
#6
#7
-
778
1196
1084
1195
1124
#8
1129
1255
1318
1215
1392
1375
#9
1)
-
#10
Average
Notes:
190
2)
295
-
291
-
1238
605
1194
1106
1283
1127
1150
1090 3)
1355 3)
1289
1360 3)
1281
1)
CHP-unit without catalyst system.
Engine-out hydrocarbon emissions.
3)
Excluding CHP-units without catalyst system.
2)
6.2
Hydrocarbon emission limit value outlook
Not counting 'odd-design' CHP-unit #4 and biogas CHP-unit #9, the hydrocarbon emissions
of the 2011 program engine population roughly ranged between 1000 and 1500 mg C/m3o at
3% O2. Arguably, this range represents the forefront of modern gas engine technology with
respect to hydrocarbon emission. As such, the lower end of this range could serve as an
ultimate guideline for what is technically feasible in terms of engine-bound measures for
hydrocarbon emission reduction across the entire engine population. Substantial enginebound reduction beyond this lower limit is unlikely given the necessity of having crevices in
the combustion chamber for adequate life-time of critical engine components, and given the
necessity of (ultra-)fuel-lean engine operation for highest power output, efficiency and fuelgas acceptance. Unfortunately, end-of-pipe hydrocarbon abatement using current oxidation
catalysts is not a viable option given the poor effectiveness of such catalysts for methane
and even ethane under typical gas engine operating conditions (see section 6.4).
Consequently, the lower end of the aforementioned range could also serve as an ultimate
guideline for possible future tightening of the BEMS hydrocarbon emission limit.
-43-
74100741-GCS 12-1002
Downward steps in the BEMS hydrocarbon ELV should give ample allowance for the
necessary efforts by engine manufacturers to thoroughly test engine design changes. Such
design changes will by necessity have an incremental character with each step requiring field
testing typically in the order of years prior to release on production engines.
6.3
Engine parameters and process conditions
Crevices i.e. narrow gaps in the combustion chamber are known to be the main source of
hydrocarbon slip in gas engines. Air-fuel mixture gets trapped in such crevices during the
compression phase of the engine process. This trapped mixture escapes combustion as the
approaching flame-front will extinguish due to cold-wall flame-quenching in the relatively cold
crevices. During the expansion and subsequent exhaust phase of the combustion process,
the unburned air-fuel mixture will be released from the crevices and is expelled with the other
combustion products into the exhaust system of the gas engine. The amount of mixture
escaping combustion, and hence an engine's hydrocarbon emission base level, is mainly
determined by the size of the crevices and the in-cylinder conditions during the combustion
process.
The so-called piston top-land crevice between piston and cylinder liner above the top
compression ring typically is the largest crevice and serves to protect the lubrication oil in the
top-ring area from overheating. Overheating of this oil would lead to accelerated oil deterioration and carbon build up in the top-ring area and consequently to excessive wear of the
piston (rings) and cylinder liner, resulting in loss of engine performance, excessive lubrication
oil consumption, premature and extended engine down-time and ultimately to premature
engine failure. Engine manufacturers thus face a delicate balancing act in reducing the size
of the piston top-land crevice and its associated hydrocarbon emissions and fuel-loss, while
maintaining acceptable engine life-time. Hence the earlier appeal for sensible timing of
possible future changes in hydrocarbon emission legislation.
The in-cylinder conditions relevant for hydrocarbon emissions are to some extent governed
by certain engine process conditions. The air-to-fuel ratio of the cylinder charge is one such
condition as e.g. fuel-leaning tends to increase flame-quenching in crevices or near the walls
of the combustion chamber. In too fuel-lean mixtures, even whole pockets of air-fuel mixture
can escape combustion. Figure 4 plots the spring and winter session's engine-out
hydrocarbon emissions against corrected oxygen fraction in the exhaust gas for the CHPunits running on natural gas. The corrected oxygen fraction is a measure of the air-to-fuel
ratio.
-44-
74100741-GCS 12-1002
CHP-units #5 and #6 best illustrate the typical sensitivity of hydrocarbon emissions to air-tofuel ratio 26 .
Sensitivity of engine-out hydrocarbon emission to air-to-fuel ratio
Hydrocarbon emission in mg C/m3o @ 3% O 2
(Round symbol = spring session, square symbol = winter session)
2250
2000
1750
1500
1250
Closed symbols = effect of change in air-to-fuel ratio
Open symbols = effect of change in air-to-fuel ratio & ignition timing
#1
#2
#3
#4
#5
#6
#7
#8
#10
1000
750
8.00
8.50
9.00
9.50
10.00
Corrected oxygen fraction in %-v (dry)
10.50
11.00
Figure 4 Sensitivity of engine-out hydrocarbon emissions to corrected oxygen fraction in the exhaust
gas (corrected oxygen fraction is a measure of the air-to-fuel ratio).
Figure 4 further reveals that there is no 'golden' air-to-fuel ratio with respect to hydrocarbon
emissions. Different engines (types) will have different sets of optimum process conditions
providing the desired engine performances. CHP-units #6 and #10 e.g. prove that the high
air-to-fuel ratios typical for prechamber gas engines not necessarily implicate high
hydrocarbon emissions.
Ignition timing is another process condition affecting hydrocarbon emissions as this affects
the cylinder charge pressure during the combustion process and consequently the mass of
air-fuel mixture trapped in a crevice. The 2011 program did not provide a clear illustration of
the sensitivity of hydrocarbon slip to ignition timing, other than mild indications in the tests of
CHP-units #1 and #8.
Hydrocarbon emission further is sensitive to the intake manifold temperature as governed by
the charge cooler temperature controller. E.g. increasing the intake manifold temperature
leads to higher combustion temperatures which reduces flame-quenching in crevices or near
walls. The stable intake manifold temperatures observed in the 2011 program did not allow
illustration of this sensitivity.
26
Analysis of the sensitivity of the other CHP-units is hampered by the low 'resolution' as compared to
measurement uncertainty and/or minor shifts in other engine process conditions.
-45-
74100741-GCS 12-1002
Fuel slip in % of
fuel gas input
Misfire adds to the hydrocarbon emissions as it involves the repeated discharge of unburned
cylinder charges into the exhaust system. Misfire results from malfunctioning ignition systems
and/or overleaning of the air-fuel mixture. The share of misfire-related hydrocarbon slip
depends on the misfire-rate i.e. the frequency with which subsequent cylinder charges fail to
ignite and/or fully combust. Figure 5 illustrates the sensitivity of fuel slip to misfire rate for two
gas engine configurations with a fuel slip base level of 2%. E.g. doubling of the fuel slip for
the 1500 rpm engine from the base level of 2% to 4% would require roughly 300 misfire
events/minute (or over 15 misfire events/minute per cylinder).
Sensitivity of fuel slip to misfire rate
6
5
4
3
2
1
0
Fuel slip base level: 2%
0
50
1500 rpm, 20 cylinders
750 rpm, 12 cylinders
100 150 200 250 300 350
Misfire rate in misfire-events/minute
400
450
500
Figure 5 Sensitivity of fuel slip to misfire rate.
The electric power output stability measurement in the 2011 program proved instrumental in
detecting misfire. Power output stability is a measure of running speed variations which are a
telltale for combustion stability. Evidently, misfire is an extreme case of combustion
instability. CHP-units # 3, #5 and #8 were found to be misfiring, albeit at a very low rate still,
thus only contributing little to these units' hydrocarbon emissions. Biogas CHP-unit #9, in
both sessions, misfired at a rate considered significant for this unit's hydrocarbon emissions.
In some cases, the misfire had already been detected by the engine management system
and was corrective action planned by the supplier of the CHP-unit; in other cases, the misfire
had so far gone unnoticed.
Modern CHP-units almost all have sophisticated engine management systems capable of
proper control of the engine process conditions relevant for hydrocarbon emissions. Hence
the earlier remark on the adequate compensation for changes in atmospheric conditions
observed in the 2011 program. More and more engine management systems also include
misfire-detection allowing for early detection and subsequent correction of misfire.
Suggestion was that the modification from aluminum pistons to steel pistons in CHP-unit #10
explains for this unit's c. 50% drop in hydrocarbon emissions between the 2007 and 2009
programs. Notwithstanding the steel pistons, the hydrocarbon slip observed in the 2011
program proved roughly on a par again with the relatively high level found in the 2007
program.
-46-
74100741-GCS 12-1002
Unfortunately, analysis as to the cause of this variation by comparison of the engine
operating condition data was hampered by the lack of such data from the 2007 and 2009
programs. Clarification of the possible sense of steel pistons as an engine-design measure to
reduce hydrocarbon emissions from its suggested effect of allowing a smaller piston top-land
crevice is highly recommended.
Fouling of the combustion chamber could well be an important clue in explaining for the
substantial variation in hydrocarbon emissions for given CHP-units observed between the
2007, 2009 and 2011 programs. Such gradual fouling, mainly carbon deposits from (partially)
burned lubricating oil, could on the one hand effectively reduce crevices and hence reduce
hydrocarbon slip. On the other hand could porous deposits in the combustion chamber act as
a layer of 'microscopic' crevices effectively increasing crevice volume. By contrast, cleaning
or replacement of such fouled components during maintenance would give an instantaneous
opposite effect. Carbon build up in the combustion chamber will certainly affect engine
performances such as NOx-emissions or sensitivity to knock as a consequence of e.g. the
gradual increase in compression ratio. In turn, such gradual changes in engine performances
could lead to automatic readjustments of engine settings by the engine management system
and/or to ad-hoc manual readjustments by maintenance personnel. Irrespective of its origins,
such readjustments will affect hydrocarbon emissions too. Unfortunately, the 2011 program
maintenance monitoring did not provide conclusive evidence for a correlation between
combustion chamber fouling and hydrocarbon emissions. Clarification of the possible role of
combustion chamber fouling (and cleaning) as a root cause for scatter in subsequent
hydrocarbon emission measurements on given engines is highly recommended.
In addition to misfire-detection, the power output stability measurement proved instrumental
in correlating the level of power output variation with engine settings or engine control system
stability. The CHP-unit #6 tests best illustrated the effect of engine settings on combustion
stability as the readjustment of air-to-fuel ratio and ignition timing settings resulted in a 35%
drop in base level top-top and RMS variation in the electric power output. The CHP-unit #8
tests demonstrated the effect of engine control system stability as here the continuously
varying ignition timing was seen reflected in an unnecessary high base level top-top and
RMS variation in electric power output.
6.4
Catalyst hydrocarbon conversion
Seven of the ten CHP-units tested are equipped with a catalyst system for cleaning of the
exhaust gas. The cleaned exhaust gas is used to increase the CO2 concentration in a greenhouse in order to increase crop yield. Such catalyst systems typically comprise a SCR
section and an oxidation section.
-47-
74100741-GCS 12-1002
The SCR section serves to reduce the NOx concentration using urea/ammonia, while the
oxidation section serves to remove CO, ethene (C2H4) and residual ammonia from the
exhaust gas 27 . It is interesting to assess the hydrocarbon conversion effectiveness of the
oxidation catalyst sections, since current oxidation catalysts are known to have difficulty in
oxidizing methane and even ethane at the given exhaust gas temperatures between c. 380
and 480 oC. The methane analyzer used in the 2011 program allows a breakdown of the
observed catalyst hydrocarbon conversion into methane and non-methane conversion. The
results of this catalyst conversion assessment are shown in figure 6. Depicted are the spring
and winter session's average conversion rates on a carbon mass basis. The bars denoted
"C" represent the best-estimate conversion rates derived from the FID analyzer results after
correction 28 for its overestimation effect (see chapter 5). The methane conversion rates were
calculated using the methane analyzer data only.
Breakdown of catalyst hydrocarbon conversion rate
Catalyst hydrocarbon conversion rate in %
(Average of 7 catalyst‐equipped CHP‐units)
40%
35%
30%
Total hydrocarbon
Methane Non‐methane
M = based on 'as measured' FID results
C = based on RF‐corrected FID results
34%
25%
23%
20%
20%
39%
15%
10%
5%
1%
6%
6%
6%
5%
1%
1%
1%
0%
M C M C Winter session
Spring session
Figure 6 Breakdown of average catalyst hydrocarbon conversion rate for the
seven catalyst-equipped CHP-units.
On average, the seven catalyst systems converted just 6% of the hydrocarbons in both
sessions.
27
In some catalyst systems, part of the oxidation catalyst section is placed upstream of the SCR
section to shift the NO/NO2-balance towards NO2 in order to enhance the effectiveness of the NOxconversion in the SCR catalyst section.
28
A response factor of 1.12 for methane and 1.06 for non-methane (predominantly ethane) was
assumed, based on the apparent response factors for the FID used as given in table 13. The
corrected FID hydrocarbon levels differ slightly from those presented in figure 2. A different correction
method had to be used here since the correlation between fuel gas composition and catalyst-out
hydrocarbon composition must be assumed less strong.
-48-
74100741-GCS 12-1002
The methane fraction in the hydrocarbon emission was hardly affected by the catalyst
systems as on average only 1% was converted in either session. Of the non-methane
fraction, predominantly ethane (C2H6) and minor fractions of higher hydrocarbons, roughly
one third only was converted in both sessions. These findings confirm the poor effectiveness
of current oxidation catalysts for methane and even ethane conversion under typical gas
engine operating conditions.
The bars denoted "M" represent the conversion rates derived from the as-measured FID
analyzer results. A substantial bias, especially evident for the non-methane fraction, is seen
to the above discussed best-estimate conversion rates. The bias is a consequence of the
typical FID overestimation effect for methane, and sometimes ethane, as discussed in
chapter 5. This finding illustrates that great care should be taken when analyzing gas engine
hydrocarbon emission data produced from typical FID analyzers.
6.5
Hydrocarbon emission methane fraction
Gas chromatography measurements in the 2007 program revealed an average methane
fraction in the catalyst-out hydrocarbon emission of 93% on a carbon mass basis. The
Ministry of Infrastructure and Environment (I&M) uses this fraction to determine the
contribution of the gas engine sector to national methane emissions and associated global
warming potential from the sector's aggregated hydrocarbon emission. The methane
analyzer used in the 2011 program allows assessment of this fraction for the 2011
hydrocarbon emissions. The results are presented in figure 7.
Breakdown of HC emission in (non‐)methane fractions
(Non‐)methane emission in mg C/m3n @ 3% O2
(Average of 7 catalyst‐equipped CHP‐units)
1600
1400
M = based on 'as measured' FID results
C = based on RF‐corrected FID results
Non‐methane
Methane
1200
21.5% 12.7% 18.1% 8.7% 22.2% 13.5% 18.2% 8.8%
1000
800
600
78.5% 87.3%
81.9% 91.3%
77.8% 86.5%
81.8% 91.2%
400
200
0
M C M C M C M C
Catalyst‐out Engine‐out Catalyst‐out
Engine‐out Spring session
Winter session
Figure 7 Breakdown of average hydrocarbon emission for the seven catalystequipped CHP-units.
-49-
74100741-GCS 12-1002
Depicted are the spring and winter session's average methane and non-methane fraction of
the hydrocarbon emissions on a carbon mass basis for the seven CHP-units with a catalyst
system. The bars denoted "C" represent the best-estimate hydrocarbon emission breakdown
derived from the FID analyzer results after correction 29 for its overestimation effect (see
chapter 5). Methane fractions are based on the methane analyzer data. The c. 91% average
methane fraction in the catalyst-out hydrocarbon emission is close to the 93% observed in
2007. Measurement uncertainty and a possible minor bias in the method used for correction
of the FID analyzer results can explain for the c. 2%-point delta.
A further interesting finding concerns the methane fraction in the hydrocarbons in the engine
exhaust gas. In chapter 5, the typical good correlation between this methane fraction and
that in the fuel gas was mentioned. The composition of the fuel gases used would suggest an
average methane fraction in the engine-out hydrocarbon emission of c. 91% rather than the
c. 87% found. Measurement uncertainty and a possible bias in the FID correction method
and in that of the aforementioned correlation can explain for this c. 4%-point difference.
The methane fractions in the engine exhaust gas and in the exhaust gas downstream of
catalyst systems for CO2-dosing purposes will on average differ by roughly 2 to 4%-point on
account of the oxidation of predominantly non-methane hydrocarbons in the catalyst system.
Care should thus be taken when determining the methane fraction in the hydrocarbon
emissions from gas engines without an oxidation catalyst system as a lower methane fraction
factor than the 93% used by I&M would need to apply. A different methane fraction factor
would also need to apply for gas engines running on e.g. biogas or other than the Dutch lowcalorific natural gas.
The bars denoted "M" represent the methane and non-methane fractions derived from the
as-measured FID analyzer results. Again, a substantial bias is seen to the above discussed
best-estimate hydrocarbon emission breakdown resulting from the typical FID overestimation
effect for methane, and sometimes ethane, as discussed in chapter 5. This finding once
again illustrates that great care should be taken when analyzing gas engine hydrocarbon
emission data produced from typical FID analyzers.
29
A response factor of 1.12 for methane and 1.06 for non-methane (predominantly ethane) was
assumed, based on the apparent response factors for the FID used as given in table 13. The
corrected FID hydrocarbon levels differ slightly from those presented in figure 2. A different correction
method had to be used here since the correlation between fuel gas composition and catalyst-out
hydrocarbon composition must be assumed less strong.
-50-
7
CONCLUSIONS AND RECOMMENDATIONS
7.1
Conclusions
74100741-GCS 12-1002
ƒ
Eight of the ten CHP-units tested met the BEMS emission limit value target of 1500 mg
C/m3o at 3% O2 while running with normal state operating conditions. Two CHP-units (#4
and #5) will need specific measures to meet this target.
The hydrocarbon emissions of the natural-gas-fueled CHP-units meeting the BEMS
target roughly ranged between 1000 and 1500 mg C/m3o at 3% O2.
ƒ
Variation in hydrocarbon emission levels for given CHP-units between the two 2011
sessions is considerably less than that seen between the 2007, 2009 and 2011
programs.
Insight in engine parameters and process conditions is essential when analyzing different
sets of hydrocarbon emission data from given engines. Differences in such parameters
and conditions most probably lay at the root of the substantial variation observed
between the 2007, 2009 and 2011 programs. Gradual fouling, and cleaning during
maintenance, of the combustion chamber is thought to be of significance too.
ƒ
No significant seasonal effect on hydrocarbon emissions was found. This gives evidence
of adequate compensation by the engine management systems for changes in
atmospheric conditions.
ƒ
The suggested reducing effect on hydrocarbon emissions of the steel pistons in CHP-unit
#10 was not confirmed.
ƒ
Crevices i.e. narrow gaps in the combustion chamber are known to be the main source of
hydrocarbon slip in gas engines. Hydrocarbon emissions base level is mainly determined
by the size of these crevices and the in-cylinder conditions during combustion.
Engine manufacturers face a delicate balancing act in reducing the size of the dominant
so-called piston top-land crevice, while maintaining good top-area lubrication conditions
needed for acceptable engine life-time.
Air-to-fuel ratio, ignition timing and intake manifold temperature are the main engine
process conditions affecting the in-cylinder conditions relevant for hydrocarbon
emissions. There is no 'golden' air-to-fuel ratio with respect to hydrocarbon slip. Different
engines (types) will have different sets of optimum process conditions providing the
desired engine performances. The tests on the prechamber gas engines prove that the
high air-to-fuel ratio typical for such engines not necessarily implicates a high
hydrocarbon emission level.
-51-
74100741-GCS 12-1002
Modern CHP-units almost all have engine management systems capable of proper
control of these conditions. The aforementioned fouling of the combustion chamber could
however induce automatic readjustment of engine settings by such systems and/or adhoc manual adjustment by maintenance personnel affecting hydrocarbon emissions.
ƒ
Misfire adds to the hydrocarbon emissions as it involves the repeated discharge of
unburned cylinder charges into the exhaust system. The share of misfire-related
hydrocarbon slip depends on the misfire-rate, i.e. the frequency with which subsequent
cylinder charges fail to ignite and/or fully combust. Three natural-gas-fuelled CHP-units
(#3, #5 and #8) were found to be misfiring albeit at a very low rate still. Biogas CHP-unit
#9 misfired severely.
Modern engine management systems more and more include misfire-detection.
ƒ
The CO2-dosing catalyst systems on average removed just 6% of the hydrocarbons from
the engine exhaust gas. Conversion rate for the methane fraction was only 1% while that
for the non-methane fraction amounted to roughly 36%. This confirms the poor
effectiveness of current oxidation catalysts for methane and even ethane under typical
gas engine operating conditions.
ƒ
The average methane fraction in the hydrocarbon emissions downstream of the catalyst
systems proved close to the 93% factor as used by I&M to derive the methane fraction
from the measured hydrocarbon emission of gas engines.
A different methane fraction factor would need to apply when determining the methane
fraction for gas engines without an oxidation catalyst or running on other types of fuel
gas.
ƒ
The prescribed flame ionization detector method is found to overestimate the
hydrocarbon emissions, and the methane emissions and global warming potential
derived thereof.
The apparent characteristics of the FID analyzer used suggest an overestimation of the
hydrocarbon emissions by over 12% and this was confirmed by a comparative analysis of
the separately measured methane and hydrocarbon emissions.
7.2
ƒ
Recommendations
The lower end of the aforementioned 1000 to 1500 mg C/m3o at 3% O2 hydrocarbon
emissions range arguably represents the forefront of modern gas engine technology with
respect to hydrocarbon emissions and could serve as an ultimate guideline for possible
future tightening of the BEMS hydrocarbon emission limit.
-52-
74100741-GCS 12-1002
Downward steps in the BEMS hydrocarbon ELV should give ample allowance for the
incremental character and long-term field test requirements of engine design changes,
given the importance of crevices for the life-time of critical engine components.
ƒ
Pros and cons of options to improve the accuracy of gas engine hydrocarbon emission
measurements, and the methane emissions and global warming potential derived
thereof, should be investigated.
Possible options are:
- using methane instead of propane for span calibration of the FID-analyzer,
- mandatory correction of the FID measurement result for the FID response factors,
- direct measurement of methane emissions using readily available methane-analyzers,
- using other measurement principles e.g. gas chromatography.
In the meantime, great care should be taken when analyzing gas engine hydrocarbon
emission data produced from FID analyzers.
ƒ
The possible significance of combustion chamber fouling and cleaning for hydrocarbon
emissions should be investigated, as the direct and/or indirect consequences could
explain for scatter in hydrocarbon emissions from subsequent measurements.
ƒ
The suggested significance of steel pistons for hydrocarbon emissions should be
investigated to identify its sense as engine-design measure with respect to hydrocarbon
emission reduction.
ƒ
The reason for the low hydrocarbon emissions from biogas CHP-unit #9 should be
investigated as a potentially interesting clue for hydrocarbon emissions reduction.
-53-
74100741-GCS 12-1002
ANNEX A – TABULATED MEASUREMENT DATA
This annex gives a comprehensive, tabulated overview of the measurement data. The
overview comprises information on:
•
Test location & date
•
Fuel gas characteristics
•
Gas engine characteristics
•
Catalyst characteristics
•
Measured energy flows and electric efficiency
•
Measured gas engine process conditions
•
Measured gross electric power output variation
•
Emission data
•
Emission data statistics
•
Gas engine process condition data statistics
•
Fuel gas data
The measurement data is given per individual test location, as per the order in table A1.
Table A1 Order of presentation of the measurement data.
Sub-annex
CHP-unit
A1
#1
A2
#2
A3
#3
A4
#4
A5
#5
A6
#6
A7
#7
A8
#8
A9
#9
A10
#10
For ease of comparison, corresponding data between the 2011 spring and 2011 winter
sessions is presented on facing pages.
-54-
74100741-GCS 12-1002
A1. CHP-unit #1 (spring 2011)
Test location & date
Location
City
Date
***
***
07 April 2011
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks
hrs
hrs
hrs
***
***
***
2006
June 2006
15577
13935
16000
· None
Fuel gas characteristics
Type
Sample time
hh:mm
Lower heating value
kJ/m3o
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
1)
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
Measured energy flows and
Measurement period
Fuel gas consumption
Measurement duration
Fuel gas flow
Fuel gas consumption
Electricity production (gross)
Measurement duration
Electricity output (gross)
Efficiency (LHV-based)
***
***
--2006
June 2006
electric efficiency
12:45 - 14:15
hh:mm
660.0
m3o
92:39.65
mm:ss
427.4
m3o/h
3762.0
kW
2388
kWh
91:55.22
mm:ss
1558.7
kW
41.4
%
Measured gas engine process conditions
12:40 - 14:20
Measurement period
hh:mm
o
20.2
C
Combustion air temperature
Intake manifold press. LB/RB
bara
3.30
3.31
o
C
49.8
50.0
Intake manifold temp. LB/RB
o
434
C
Exhaust gas temperature
mm
mm
rpm
kW
bar
o
BTDC
Natural gas
14:30
31690
Vee-16
Open chamber
170
195
12.0
1500
1558
18.3 1)
25.0
Assumption: 96% generator efficiency
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
hrs
hrs
hrs
hrs
-
15577
---------
18:10 - 19:40
633.0
88:54.90
427.1
3760.1
2298
88:27.96
1558.6
41.5
18:05 - 19:45
20.4
3.28
3.30
48.3
48.3
435
Measured gross electric power output variation (relative to actual gross electric power output)
25
15
2.0
RMS variation
1.5
10
1.0
5
0.5
0
12:00 12:30 13:00
13:30 14:00 14:30 15:00
15:30 16:00 16:30 17:00
Time (hh:mm)
17:30 18:00 18:30 19:00
0.0
19:30 20:00
RMS (%)
Top-top (%)
20
2.5
Top-top variation
-55-
74100741-GCS 12-1002
A1. CHP-unit #1 (winter 2011)
Fuel gas characteristics
Type
***
Sample time
***
hh:mm
06 December 2011 Lower heating value
kJ/m3o
Test location & date
Location
City
Date
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks
hrs
hrs
hrs
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
***
***
***
2006
June 2006
16714
15603
17600
· None
1)
2)
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
Measured energy flows and
Measurement period
Fuel gas consumption
Measurement duration
Fuel gas flow
Fuel gas consumption
Electricity production (gross)
Measurement duration
Electricity output (gross)
Efficiency (LHV-based)
-
mm
mm
rpm
kW
bar
o
BTDC
Vee-16
Open chamber
170
195
12.0
1500
1558
18.3 1)
25.0 2)
Assumption: 96% generator efficiency
Actual ignition timing w as c. 26.0 oBTDC
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
***
***
--2006
June 2006
Natural gas
12:15
31660
electric efficiency
12:35 - 14:05
hh:mm
642.0
m3o
90:12.93
mm:ss
427.0
m3o/h
3755.0
kW
2346
kWh
90:33.85
mm:ss
1554.3
kW
41.4
%
hrs
hrs
hrs
hrs
-
--6851
-------
16:10 - 17:40
639.0
89:54.83
426.4
3750.0
2322
89:35.93
1554.9
41.5
Measured gas engine process conditions
12:30 - 13:35
Measurement period
hh:mm
o
14.3
C
Combustion air temperature
Intake manifold press. LB/RB
bara
3.28
3.30
o
C
47.1
46.0
Intake manifold temp. LB/RB
o
427
C
Exhaust gas temperature
16:05 - 17:45
12.8
3.28
3.31
47.8
46.8
---
Measured gross electric power output variation (relative to actual gross electric power output)
2.5
20
Top-top variation
2.0
RMS variation
15
1.5
10
1.0
5
0.5
0
12:00
12:30
13:00
13:30
14:00
14:30
15:00
15:30
Time (hh:mm)
16:00
16:30
17:00
17:30
0.0
18:00
RMS (%)
Top-top (%)
25
-56-
74100741-GCS 12-1002
A1. CHP-unit #1 (spring 2011)
Emission data
Start
Stop
hh:mm
hh:mm
1
12:45
13:15
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
O2
CO2
CO
NO
NOx
2
13:15
13:45
Test series
3
4
13:45
18:10
14:15
18:40
Exhaust gas sampling
5
18:40
19:10
Engine-out
Catalyst-out
n/a
post
on
on
to chimney
to chimney
Atmospheric conditions
1027
1026
1027
1028
19.3
19.6
16.6
15.4
51
54
66
70
Measured emissions
6
19:10
19:40
mbar
o
C
%
1027
19.6
50
%-v (dry)
9.24
9.28
9.28
9.31
9.35
9.32
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
6.10
469
214
278
6.00
470
199
264
6.00
470
197
263
6.10
<1
6
8
6.00
<1
5
8
6.10
<1
6
9
975
963
1028
14.4
70
CH4
ppm-v (dry)
970
977
955
946
Cx Hy (as C3H8)
ppm-v (wet)
353
366
370
353
Combustion stoichiometry
350
347
%-v (dry)
-
9.06
1.70
9.10
9.10
9.14
1.70
1.70
1.71
Calculated emissions (dry)
9.18
1.71
9.15
1.71
CO
mg/m3o @ 3 %-v O2
899
904
904
<2
<2
<2
NO as NO2
mg/m3o @ 3 %-v O2
672
627
621
17
17
18
NOx as NO2
mg/m3o @ 3 %-v O2
874
832
829
25
24
27
CH4
mg/m3o @ 3 %-v O2
1062
1073
1071
1060
1055
1042
Cx Hy as C
mg/m3o @ 3 %-v O2
988
1028
1039
964
959
Cx Hy as CH4
mg/m3o @ 3 %-v O2
1317
CO
NO as NO2
g/GJ
g/GJ
255
191
1370
1385
1286
1279
Calculated specific emissions
257
257
<1
<1
178
176
5
5
NOx as NO2
g/GJ
248
236
235
7
7
8
CH4
g/GJ
301
305
304
301
300
296
Cx Hy as C
g/GJ
280
292
295
274
272
Cx Hy as CH4
g/GJ
374
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
1.5
7.0
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n/a
11.8
n/a
11.8
m3o/h
5920
---
O2 (complete combustion)
Air-to-fuel ratio (λ)
Notes:
1)
389
393
365
363
Calculated hydrocarbon slip
1.5
1.5
1.5
1.5
7.3
7.3
6.8
6.8
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n/a
11.8
--427.3
960
1280
<1
5
273
364
1.5
6.8
45
9.1
45
9.1
47
10.2
---
---
---
m 3o/h.
-57-
74100741-GCS 12-1002
A1. CHP-unit #1 (winter 2011)
Emission data
Start
Stop
hh:mm
hh:mm
1
12:35
13:05
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
O2
CO2
CO
NO
NOx
2
13:05
13:35
Test series
3
4
13:35
16:10
14:05
16:40
Exhaust gas sampling
5
16:40
17:10
Engine-out
Catalyst-out
n/a
post
on
on
to chimney
to chimney
Atmospheric conditions
1002
1002
1003
1003
7
7
6
6
89
82
82
82
Measured emissions
6
17:10
17:40
mbar
o
C
%
1002
6
86
%-v (dry)
9.33
9.32
9.32
9.31
9.30
9.29
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
6.10
488
185
265
6.10
488
184
264
6.10
488
185
265
6.20
<1
6
9
6.20
<1
6
9
6.20
<1
6
9
986
972
1004
5
88
CH4
ppm-v (dry)
986
986
973
969
Cx Hy (as C3H8)
ppm-v (wet)
380
379
375
355
Combustion stoichiometry
360
361
%-v (dry)
-
9.15
1.71
9.14
9.14
9.14
1.71
1.71
1.71
Calculated emissions (dry)
9.13
1.71
9.12
1.70
CO
mg/m3o @ 3 %-v O2
942
941
941
<2
<2
<2
NO as NO2
mg/m3o @ 3 %-v O2
586
582
585
18
19
18
NOx as NO2
mg/m3o @ 3 %-v O2
839
835
838
29
28
28
CH4
mg/m3o @ 3 %-v O2
1088
1087
1087
1070
1070
1065
Cx Hy as C
mg/m3o @ 3 %-v O2
1072
1068
1057
998
1002
1003
Cx Hy as CH4
mg/m3o @ 3 %-v O2
1429
1337
CO
NO as NO2
g/GJ
g/GJ
267
166
1424
1410
1331
1336
Calculated specific emissions
267
267
<1
<1
165
166
5
5
NOx as NO2
g/GJ
238
237
238
8
8
8
CH4
g/GJ
309
308
308
304
304
302
Cx Hy as C
g/GJ
304
303
300
283
284
Cx Hy as CH4
g/GJ
406
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
1.5
7.6
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n/a
11.8
n/a
11.8
m3o/h
5922
---
O2 (complete combustion)
Air-to-fuel ratio (λ)
Notes:
1)
404
400
378
379
Calculated hydrocarbon slip
1.5
1.5
1.5
1.5
7.5
7.5
7.1
7.1
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n/a
11.8
--426.7
<1
5
285
380
1.5
7.1
49
11.7
48
10.8
47
10.7
5904
---
---
m 3o/h.
-58-
74100741-GCS 12-1002
A1. CHP-unit #1 (spring 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
12:45
13:15
9.18
9.31
9.24
0.026
6.0
6.1
6.1
0.02
465
474
469
1.8
194
241
214
8.8
258
306
278
9.0
328
376
353
9.3
945
992
970
9.7
2
13:15
13:45
9.22
9.33
9.28
0.027
6.0
6.1
6.0
0.02
465
476
470
2.1
181
218
199
7.1
244
283
264
7.5
350
383
366
7.4
955
1008
977
9.3
Test series
3
4
13:45
18:10
14:15
18:40
9.21
9.23
9.32
9.42
9.28
9.31
0.025
0.037
6.0
6.0
6.1
6.1
6.0
6.1
0.02
0.03
465
0
476
2
470
1
2.0
0.2
174
4.7
220
15.2
197
5.5
8.1
1.32
239
6.7
286
22.1
263
7.8
8.4
1.90
354
333
392
377
370
353
7.9
9.2
948
923
1009
1000
975
963
10.7
16.4
5
18:40
19:10
9.27
9.45
9.35
0.048
5.9
6.1
6.0
0.04
0
1
1
0.3
4.8
9.7
5.4
0.82
6.5
14.0
7.5
1.22
331
374
350
8.9
929
992
955
12.5
6
19:10
19:40
9.25
9.37
9.32
0.027
6.0
6.1
6.1
0.02
0
1
1
0.2
4.8
11.1
5.8
1.31
7.0
16.7
8.6
1.97
331
363
347
7.2
921
971
946
10.1
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold press. LB/RB
Intake manifold temp. LB/RB
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
12:40 - 14:20
19.2
22.5
20.2
0.48
3.20
/
3.22
3.38
/
3.38
3.30
/
3.31
0.035
/
0.030
46.4
/
46.6
51.7
/
51.8
49.8
/
50.0
1.39
/
1.37
433
435
434
0.4
4+5+6
18:05 - 19:45
18.7
22.6
20.4
0.62
3.18
/
3.20
3.38
/
3.38
3.28
/
3.30
0.035
/
0.029
45.2
/
45.2
51.0
/
50.9
48.3
/
48.3
1.41
/
1.39
434
437
435
0.8
-59-
74100741-GCS 12-1002
A1. CHP-unit #1 (winter 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
12:35
13:05
9.28
9.39
9.33
0.026
6.1
6.2
6.1
0.02
482
493
488
2.0
163
213
185
10.8
241
295
265
11.8
343
404
380
12.5
947
1022
986
14.8
2
13:05
13:35
9.27
9.37
9.32
0.025
6.1
6.2
6.1
0.02
484
493
488
2.1
157
208
184
10.3
234
289
264
11.3
354
406
379
11.4
949
1023
986
14.1
Test series
3
4
13:35
16:10
14:05
16:40
9.14
9.26
9.42
9.38
9.32
9.31
0.047
0.027
6.1
6.2
6.2
6.3
6.1
6.2
0.03
0.02
482
0
501
2
488
1
2.3
0.3
110
4.5
216
7.4
185
5.8
13.0
0.55
181
7.3
300
11.2
265
9.1
14.3
0.85
334
322
430
390
375
355
13.9
12.9
945
934
1149
1010
986
972
18.0
16.0
5
16:40
17:10
9.24
9.35
9.30
0.026
6.2
6.2
6.2
0.02
0
1
1
0.3
4.8
6.9
5.9
0.47
7.4
10.7
9.0
0.73
337
382
360
11.9
942
1006
973
13.6
6
17:10
17:40
9.23
9.37
9.29
0.028
6.2
6.3
6.2
0.02
0
2
1
0.3
4.8
7.4
5.8
0.50
7.3
11.2
9.0
0.75
338
385
361
12.1
934
1014
969
14.2
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold press. LB/RB
Intake manifold temp. LB/RB
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
12:30 - 13:35
11.5
17.2
14.3
1.01
3.18
/
3.23
3.36
/
3.36
3.28
/
3.30
0.032
/
0.024
39.0
/
45.6
52.3
/
46.4
47.0
/
46.0
1.87
/
0.14
427
429
427
0.3
4+5+6
16:05 - 17:45
10.2
18.8
12.8
1.16
3.20
/
3.23
3.37
/
3.37
3.28
/
3.31
0.032
/
0.025
46.7
/
45.7
49.7
/
48.6
47.8
/
46.8
0.56
/
0.54
---------
-60-
A1. CHP-unit #1 (spring 2011)
74100741-GCS 12-1002
-61-
A1. CHP-unit #1 (winter 2011)
74100741-GCS 12-1002
-62-
74100741-GCS 12-1002
A2. CHP-unit #2 (spring 2011)
Test location & date
Location
City
Date
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks
-
***
***
08 April 2011
hrs
hrs
hrs
***
***
***
2006
December 2006
18038
17225
18255
· None
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
Measured energy flows and
Measurement period
Fuel gas consumption
Measurement duration
Fuel gas flow
Fuel gas consumption
Electricity production (gross)
Measurement duration
Electricity output (gross)
Efficiency (LHV-based)
***
***
----January 2007
Fuel gas characteristics
Type
Sample time
hh:mm
Lower heating value
kJ/m3o
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
mm
mm
rpm
kW
bar
o
BTDC
Natural gas
12:20
31650
Vee-16
Open chamber
170
210
12.0
1500
1562
17.1 1)
22.0 2)
1)
Assumption: 96% generator efficiency
2)
Cont. adjustment betw een c. 1.5o and 2.5o retard on all cyl's
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
electric efficiency
12:45 - 14:15
hh:mm
660.0
m3o
89:54.12
mm:ss
440.5
m3o/h
kW
3872.6
kWh
2322.56
89:55.15
mm:ss
1549.8
kW
40.0
%
Measured gas engine process conditions
12:40 - 14:20
Measurement period
hh:mm
o
C
22.1
Combustion air temperature
Intake manifold press. LB/RB
bara
3.16
3.15
o
46.9
C
Intake manifold temperature
o
477
C
Exhaust gas temperature
hrs
hrs
hrs
hrs
-
18039
7603
-------
15:00 - 16:30
657.0
89:33.08
440.2
3870.0
2311.68
89:34.13
1548.5
40.0
14:55 - 16:35
24.3
3.16
3.15
47.0
479
Measured gross electric power output variation (relative to actual gross electric power output)
2.5
25
15
2.0
RMS variation
1.5
10
1.0
5
0.5
0
12:00
12:30
13:00
13:30
14:00
14:30
Time (hh:mm)
15:00
15:30
16:00
16:30
0.0
17:00
RMS (%)
Top-top (%)
20
Top-top variation
-63-
74100741-GCS 12-1002
A2. CHP-unit #2 (winter 2011)
Test location & date
Location
City
Date
Fuel gas characteristics
Type
***
Sample time
***
hh:mm
29 November 2011 Lower heating value
kJ/m3o
-
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks
hrs
hrs
hrs
***
***
***
2006
December 2006
19256
19219
20719
· At last maintenance, cylinder heads and pistons w ere cleaned to
prevent knock-induced ignition timing adjustment
· Type A maintenance interval increased from 1000 to 1500 running hours
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
Measured energy flows and
Measurement period
Fuel gas consumption
Measurement duration
Fuel gas flow
Fuel gas consumption
Electricity production (gross)
Measurement duration
Electricity output (gross)
Efficiency (LHV-based)
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
Vee-16
Open chamber
170
210
12.0
1500
1562
17.1 1)
22.0 2)
1)
Assumption: 96% generator efficiency
2)
Stable ignition timing; see Maintenance remarks
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
***
***
------January 2007
mm
mm
rpm
kW
bar
o
BTDC
Natural gas
11:30
31680
electric efficiency
11:45 - 13:15
hh:mm
656.0
m3o
90:01.83
mm:ss
437.2
m3o/h
kW
3847.2
kWh
2317.44
89:29.18
mm:ss
1553.8
kW
40.4
%
hrs
hrs
hrs
hrs
-
19256
8159
19228
---------
13:50 - 15:20
656.0
89:59.06
437.4
3849.2
2320
89:36.17
1553.5
40.4
Measured gas engine process conditions
11:40 - 13:20
Measurement period
hh:mm
o
C
14.3
Combustion air temperature
Intake manifold press. LB/RB
bara
3.04
3.03
o
47.0
C
Intake manifold temperature
o
464
C
Exhaust gas temperature
13:45 - 15:25
14.5
3.05
3.03
47.0
464
Measured gross electric power output variation (relative to actual gross electric power output)
20
15
2.5
Top-top variation
2.0
RMS variation
1.5
10
1.0
5
0.5
0
11:00
11:30
12:00
12:30
13:00
13:30
Time (hh:mm)
14:00
14:30
15:00
15:30
0.0
16:00
RMS (%)
Top-top (%)
25
-64-
74100741-GCS 12-1002
A2. CHP-unit #2 (spring 2011)
Emission data
Start
Stop
hh:mm
hh:mm
1
12:45
13:15
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
2
13:15
13:45
Test series
3
4
13:45
15:00
14:15
15:30
Exhaust gas sampling
5
15:30
16:00
Engine-out
Catalyst-out
n/a
post
on
on
to chimney
to chimney
Atmospheric conditions
1026
1025
1024
1024
18
18
19
19
52
53
50
49
Measured emissions
6
16:00
16:30
mbar
o
C
%
1026
16
57
%-v (dry)
9.39
9.41
9.40
9.34
9.33
9.34
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
6.10
478
91
157
6.10
478
90
155
6.10
477
91
157
6.10
<1
10
14
6.10
<1
11
14
6.10
<1
10
14
CH4
ppm-v (dry)
1196
1206
1208
1173
1172
1178
Cx Hy (as C3H8)
ppm-v (wet)
447
446
446
438
Combustion stoichiometry
425
423
%-v (dry)
-
9.16
1.71
9.18
9.17
9.13
1.71
1.71
1.71
Calculated emissions (dry)
9.12
1.71
9.13
1.71
CO
mg/m3o @ 3 %-v O2
928
929
927
<2
<2
<2
NO as NO2
mg/m3o @ 3 %-v O2
290
287
290
33
33
32
NOx as NO2
mg/m3o @ 3 %-v O2
499
494
499
45
45
44
CH4
mg/m3o @ 3 %-v O2
1326
1339
1340
1295
1293
1300
Cx Hy as C
mg/m3o @ 3 %-v O2
1264
1263
1263
1234
1197
1192
Cx Hy as CH4
mg/m3o @ 3 %-v O2
1685
1589
CO
NO as NO2
g/GJ
g/GJ
264
82
1685
1684
1646
1596
Calculated specific emissions
264
263
<1
<1
81
82
9
9
NOx as NO2
g/GJ
142
140
142
13
13
12
CH4
g/GJ
377
380
381
368
367
369
Cx Hy as C
g/GJ
359
359
359
351
340
Cx Hy as CH4
g/GJ
479
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
1.9
8.9
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n/a
11.6
n/a
11.6
m3o/h
6130
---
O2
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
Notes:
1)
478
478
467
453
Calculated hydrocarbon slip
1.9
1.9
1.8
1.8
8.9
8.9
8.7
8.5
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n/a
11.6
--440.4
1024
19
49
<1
9
339
451
1.8
8.4
54
11.6
54
11.6
54
11.6
---
---
---
m 3o/h.
-65-
74100741-GCS 12-1002
A2. CHP-unit #2 (winter 2011)
Emission data
Start
Stop
hh:mm
hh:mm
1
11:45
12:15
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
2
12:15
12:45
Test series
3
4
12:45
13:50
13:15
14:20
Exhaust gas sampling
5
14:20
14:50
Engine-out
Catalyst-out
n/a
post
on
on
to chimney
to chimney
Atmospheric conditions
1013
1012
1011
1011
9
10
10
10
76
72
70
70
Measured emissions
6
14:50
15:20
mbar
o
C
%
1014
9
79
%-v (dry)
9.25
9.24
9.25
9.25
9.24
9.24
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
6.20
537
154
234
6.20
536
153
237
6.20
536
153
239
6.30
<1
11
15
6.30
<1
11
15
6.20
<1
11
15
CH4
ppm-v (dry)
1167
1164
1166
1154
1153
1151
Cx Hy (as C3H8)
ppm-v (wet)
442
440
432
411
Combustion stoichiometry
410
398
%-v (dry)
-
9.03
1.69
9.02
9.03
9.04
1.69
1.69
1.69
Calculated emissions (dry)
9.03
1.69
9.03
1.69
CO
mg/m3o @ 3 %-v O2
1030
1027
1028
<2
<2
<2
NO as NO2
mg/m3o @ 3 %-v O2
484
481
481
35
35
35
NOx as NO2
mg/m3o @ 3 %-v O2
736
745
752
48
48
48
CH4
mg/m3o @ 3 %-v O2
1278
1274
1277
1264
1262
1260
Cx Hy as C
mg/m3o @ 3 %-v O2
1235
1228
1208
1142
1138
1105
Cx Hy as CH4
mg/m3o @ 3 %-v O2
1647
1473
CO
NO as NO2
g/GJ
g/GJ
292
137
1638
1611
1522
1517
Calculated specific emissions
291
292
<1
<1
136
137
10
10
NOx as NO2
g/GJ
209
211
213
14
14
14
CH4
g/GJ
363
361
362
359
358
357
Cx Hy as C
g/GJ
350
348
343
324
323
Cx Hy as CH4
g/GJ
467
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
1.8
8.7
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n/a
11.6
n/a
11.6
m3o/h
6030
---
O2
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
Notes:
1)
465
457
432
430
Calculated hydrocarbon slip
1.8
1.8
1.8
1.8
8.7
8.5
8.1
8.0
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n/a
11.6
--437.3
1010
10
70
<1
10
313
418
1.8
7.8
50
11.0
49
11.0
50
11.0
6027
---
---
m 3o/h.
-66-
74100741-GCS 12-1002
A2. CHP-unit #2 (spring 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
12:45
13:15
9.32
9.45
9.39
0.027
6.1
6.1
6.1
0.02
474
482
478
1.6
77
103
91
6.2
140
170
157
7.0
426
466
447
8.1
1178
1216
1196
7.8
2
13:15
13:45
9.33
9.46
9.41
0.028
6.0
6.1
6.1
0.02
473
484
478
2.3
72
101
90
7.0
135
168
155
7.7
411
464
446
9.2
1185
1228
1206
8.1
Test series
3
4
13:45
15:00
14:15
15:30
9.33
9.26
9.46
9.40
9.40
9.34
0.031
0.032
6.0
6.1
6.1
6.2
6.1
6.1
0.02
0.02
473
-1
482
0
477
-1
2.1
0.3
75
9.5
104
11.6
91
10.4
6.7
0.50
138
12.8
171
15.7
157
14.2
7.5
0.67
428
413
464
457
446
438
8.2
9.2
1182
1145
1237
1207
1208
1173
11.5
11.1
5
15:30
16:00
9.26
9.38
9.33
0.028
6.1
6.2
6.1
0.02
-1
0
-1
0.2
9.6
11.9
10.5
0.52
13.0
16.0
14.2
0.69
410
443
425
7.7
1147
1188
1172
8.3
6
16:00
16:30
9.28
9.38
9.34
0.025
6.1
6.2
6.1
0.02
-1
-1
-1
0.2
9.4
11.4
10.2
0.51
12.8
15.4
13.8
0.67
404
440
423
8.1
1157
1198
1178
9.2
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold press. LB/RB
Intake manifold temperature
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
12:40 - 14:20
20.4
25.1
22.1
0.68
3.06
/
3.03
3.27
/
3.33
3.16
/
3.15
0.040
/
0.047
46.7
47.3
46.9
0.10
474
481
477
1.1
4+5+6
14:55 - 16:35
22.6
25.7
24.3
0.60
3.06
/
3.04
3.28
/
3.30
3.16
/
3.15
0.044
/
0.047
46.5
47.4
47.0
0.16
476
482
479
1.1
-67-
74100741-GCS 12-1002
A2. CHP-unit #2 (winter 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
11:45
12:15
9.21
9.28
9.25
0.021
6.1
6.2
6.2
0.02
533
540
537
1.6
137
167
154
4.9
217
248
234
5.8
417
460
442
10.6
1156
1182
1167
4.4
2
12:15
12:45
9.20
9.28
9.24
0.022
6.1
6.2
6.1
0.02
532
540
536
1.8
139
167
153
5.3
221
254
237
6.3
417
462
440
10.6
1153
1174
1164
4.5
Test series
3
4
12:45
13:50
13:15
14:20
9.21
9.20
9.28
9.28
9.25
9.25
0.022
0.022
6.1
6.2
6.2
6.3
6.1
6.3
0.02
0.02
532
0
540
1
536
1
1.8
0.2
143
10.0
169
15.6
153
11.0
4.9
0.84
227
13.8
259
21.2
239
15.2
6.1
1.14
405
390
450
429
432
411
12.6
10.4
1155
1143
1174
1163
1166
1154
4.5
4.0
5
14:20
14:50
9.20
9.28
9.24
0.022
6.2
6.3
6.2
0.02
0
2
1
0.4
10.0
15.6
11.1
0.99
13.8
21.2
15.3
1.35
385
430
410
10.6
1142
1165
1153
4.3
6
14:50
15:20
9.20
9.27
9.24
0.021
6.2
6.3
6.2
0.02
1
2
1
0.3
10.0
16.0
11.1
0.94
13.9
22.1
15.4
1.29
378
420
398
10.4
1140
1164
1151
4.5
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold press. LB/RB
Intake manifold temperature
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
11:40 - 13:20
13.5
16.3
14.3
0.31
2.96
/
3.00
3.11
/
3.06
3.04
/
3.03
0.018
/
0.006
46.7
47.8
47.0
0.21
463
465
464
0.3
4+5+6
13:45 - 15:25
14.0
15.8
14.5
0.21
3.02
/
2.99
3.07
/
3.05
3.05
/
3.03
0.006
/
0.006
46.1
47.3
47.0
0.26
463
465
464
0.2
-68-
A2. CHP-unit #2 (spring 2011)
74100741-GCS 12-1002
-69-
A2. CHP-unit #2 (winter 2011)
74100741-GCS 12-1002
-70-
74100741-GCS 12-1002
A3. CHP-unit #3 (spring 2011)
Test location & date
Location
City
Date
***
***
18 April 2011
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks:
hrs
hrs
hrs
***
***
***
2007
March 2007
19763
18505
20505
· Recently occasional misfire: some spark plugs w ere replaced.
· Next maintenance rescheduled to day after measurement.
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
Fuel gas characteristics
Type
Sample time
hh:mm
Lower heating value
kJ/m3o
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
1)
Vee-20
Open chamber
135
170
12.5
1500
1064
18.2 1)
20.0
Assumption: 96% generator efficiency
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
n/a
n/a
n/a
n/a
n/a
mm
mm
rpm
kW
bar
o
BTDC
Natural gas
12:05
32530
Measured energy flows and electric efficiency
Measurement period
hh:mm
12:15 - 13:45
Fuel gas consumption
m 3o
454.8
Measurement duration
mm:ss
89:48.16
303.9
Fuel gas flow
m3o/h
Fuel gas consumption
kW
2745.9
Electricity production (gross)
kWh
1605
Measurement duration
mm:ss
90:30.07
Electricity output (gross)
kW
1064.1
Efficiency (LHV-based)
%
38.8
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
Measured gas engine process conditions
Measurement period
hh:mm
12:10 - 13:50
o
Combustion air temperature
C
20.5
Intake manifold pressure
bara
3.34
o
Intake manifold temperature
C
44.6
o
C
451
Exhaust gas temperature
n/a
n/a
n/a
n/a
n/a
hrs
hrs
hrs
hrs
-
n/a
n/a
n/a
n/a
n/a
Measured gross electric power output variation (relative to actual gross electric power output)
25
15
2.0
RMS variation
1.5
10
1.0
5
0.5
0
11:00
11:30
12:00
12:30
13:00
13:30
Time (hh:mm)
14:00
14:30
15:00
15:30
0.0
16:00
RMS (%)
Top-top (%)
20
2.5
Top-top variation
-71-
74100741-GCS 12-1002
A3. CHP-unit #3 (winter 2011)
Test location & date
Location
City
Date
Fuel gas characteristics
Type
***
***
Sample time
hh:mm
23 December 2011 Lower heating value
kJ/m3o
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks:
hrs
hrs
hrs
***
***
***
2007
March 2007
22943
21760
23760
· Occasional misfire.
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
1)
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
Vee-20
Open chamber
135
170
12.5
1500
1064
18.2 1)
20.0
Assumption: 96% generator efficiency
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
n/a
n/a
n/a
n/a
n/a
mm
mm
rpm
kW
bar
o
BTDC
Natural gas
10:20
32050
Measured energy flows and electric efficiency
Measurement period
hh:mm
11:00 - 12:30
Fuel gas consumption
m 3o
462.4
Measurement duration
mm:ss
89:23.98
310.3
Fuel gas flow
m3o/h
Fuel gas consumption
kW
2762.7
Electricity production (gross)
kWh
1582
Measurement duration
mm:ss
89:18.24
Electricity output (gross)
kW
1062.9
Efficiency (LHV-based)
%
38.5
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
Measured gas engine process conditions
Measurement period
hh:mm
10:55 - 12:35
o
Combustion air temperature
C
14.6
Intake manifold pressure
bara
3.38
o
Intake manifold temperature
C
47.2
o
C
452
Exhaust gas temperature
n/a
n/a
n/a
n/a
n/a
hrs
hrs
hrs
hrs
-
n/a
n/a
n/a
n/a
n/a
Measured gross electric power output variation (relative to actual gross electric power output)
20
15
2.5
Top-top variation
2.0
RMS variation
1.5
10
1.0
5
0.5
0
10:00
10:30
11:00
11:30
12:00
12:30
Time (hh:mm)
13:00
13:30
14:00
14:30
0.0
15:00
RMS (%)
Top-top (%)
25
-72-
74100741-GCS 12-1002
A3. CHP-unit #3 (spring 2011)
Emission data
Start
Stop
hh:mm
hh:mm
1
12:15
12:45
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
2
12:45
13:15
Test series
3
4
13:15
n/a
13:45
n/a
Exhaust gas sampling
Engine-out
post
n/a
to chimney
Atmospheric conditions
1023
1023
n/a
19
19
n/a
30
30
n/a
Measured emissions
mbar
o
C
%
1024
18
33
%-v (dry)
9.23
9.24
9.23
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
6.30
551
101
210
6.30
552
108
220
6.30
552
110
225
CH4
ppm-v (dry)
1003
1007
1008
Cx Hy (as C3H8)
ppm-v (wet)
398
383
384
n/a
Combustion stoichiometry
%-v (dry)
-
9.04
1.69
CO
mg/m3o @ 3 %-v O2
NO as NO2
mg/m3o @ 3 %-v O2
NOx as NO2
5
n/a
n/a
6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
9.05
9.04
n/a
1.69
1.69
n/a
Calculated emissions (dry)
n/a
n/a
n/a
n/a
1055
1058
1057
n/a
n/a
n/a
317
339
345
n/a
n/a
n/a
mg/m3o @ 3 %-v O2
659
691
706
n/a
n/a
n/a
CH4
mg/m3o @ 3 %-v O2
1097
1102
1102
n/a
n/a
n/a
Cx Hy as C
mg/m3o @ 3 %-v O2
1086
1044
1046
n/a
n/a
n/a
Cx Hy as CH4
mg/m3o @ 3 %-v O2
1447
n/a
n/a
CO
NO as NO2
g/GJ
g/GJ
299
90
1393
1395
Calculated specific
299
299
96
98
n/a
n/a
n/a
n/a
NOx as NO2
g/GJ
187
196
200
n/a
n/a
n/a
CH4
g/GJ
310
312
312
n/a
n/a
n/a
Cx Hy as C
g/GJ
307
296
296
n/a
n/a
Cx Hy as CH4
g/GJ
410
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
1.6
7.7
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n/a
9.6
n/a
9.5
m3o/h
4290
---
O2
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
Notes:
1)
n/a
emissions
n/a
n/a
394
395
n/a
n/a
Calculated hydrocarbon slip
1.6
1.6
n/a
n/a
7.4
7.4
n/a
n/a
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n/a
9.5
--303.9
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
---
---
---
m 3o/h.
-73-
74100741-GCS 12-1002
A3. CHP-unit #3 (winter 2011)
Emission data
Start
Stop
hh:mm
hh:mm
1
11:00
11:30
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
2
11:30
12:00
Test series
3
4
12:00
n/a
12:30
n/a
Exhaust gas sampling
Engine-out
post
n/a
to chimney
Atmospheric conditions
1018
1018
n/a
10
10
n/a
95
97
n/a
Measured emissions
mbar
o
C
%
1018
11
88
%-v (dry)
9.19
9.17
9.18
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
6.20
554
71
179
6.20
553
70
177
6.20
553
70
176
CH4
ppm-v (dry)
1077
1074
1072
Cx Hy (as C3H8)
ppm-v (wet)
425
426
432
n/a
Combustion stoichiometry
%-v (dry)
-
8.99
1.69
CO
mg/m3o @ 3 %-v O2
NO as NO2
mg/m3o @ 3 %-v O2
NOx as NO2
5
n/a
n/a
6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
8.97
8.98
n/a
1.68
1.68
n/a
Calculated emissions (dry)
n/a
n/a
n/a
n/a
1057
1053
1054
n/a
n/a
n/a
222
219
219
n/a
n/a
n/a
mg/m3o @ 3 %-v O2
560
553
550
n/a
n/a
n/a
CH4
mg/m3o @ 3 %-v O2
1174
1168
1167
n/a
n/a
n/a
Cx Hy as C
mg/m3o @ 3 %-v O2
1160
1162
1179
n/a
n/a
n/a
Cx Hy as CH4
mg/m3o @ 3 %-v O2
1547
n/a
n/a
CO
NO as NO2
g/GJ
g/GJ
299
63
1549
1572
Calculated specific
298
299
62
62
n/a
n/a
n/a
n/a
NOx as NO2
g/GJ
159
157
156
n/a
n/a
n/a
CH4
g/GJ
333
331
331
n/a
n/a
n/a
Cx Hy as C
g/GJ
329
329
334
n/a
n/a
Cx Hy as CH4
g/GJ
438
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
1.7
8.2
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n/a
9.9
n/a
10.0
m3o/h
4299
---
O2
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
Notes:
1)
n/a
emissions
n/a
n/a
439
445
n/a
n/a
Calculated hydrocarbon slip
1.7
1.7
n/a
n/a
8.2
8.3
n/a
n/a
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n/a
10.1
--310.3
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
---
---
---
m 3o/h.
-74-
74100741-GCS 12-1002
A3. CHP-unit #3 (spring 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
12:15
12:45
9.19
9.27
9.23
0.020
6.2
6.3
6.3
0.02
547
554
551
1.6
90
109
101
2.9
196
218
210
3.5
376
412
398
8.5
986
1033
1003
8.1
2
12:45
13:15
9.20
9.29
9.24
0.023
6.2
6.3
6.3
0.02
548
555
552
1.6
98
119
108
4.2
207
232
220
6.0
341
405
383
9.9
996
1026
1007
4.9
Test series
3
4
13:15
n/a
13:45
n/a
9.20
n/a
9.27
n/a
9.23
n/a
0.020
n/a
6.3
n/a
6.3
n/a
6.3
n/a
0.02
n/a
545
n/a
557
n/a
552
n/a
2.5
n/a
102
n/a
117
n/a
110
n/a
3.1
n/a
217
n/a
234
n/a
225
n/a
3.6
n/a
368
n/a
404
n/a
384
n/a
7.4
n/a
1000
n/a
1031
n/a
1008
n/a
5.4
n/a
5
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
12:10 - 13:50
19.6
22.3
20.5
0.33
3.28
3.37
3.34
0.010
44.3
44.8
44.6
0.14
450
451
451
0.2
4+5+6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
-75-
74100741-GCS 12-1002
A3. CHP-unit #3 (winter 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
11:00
11:30
9.15
9.24
9.19
0.022
6.2
6.3
6.2
0.02
550
558
554
1.8
60
76
71
2.4
163
186
179
3.2
402
443
425
11.7
1051
1101
1077
6.4
2
11:30
12:00
9.14
9.21
9.17
0.021
6.1
6.3
6.2
0.02
549
556
553
1.6
66
76
70
1.9
169
184
177
2.3
395
446
426
12.1
1045
1091
1074
5.3
Test series
3
4
12:00
n/a
12:30
n/a
9.14
n/a
9.21
n/a
9.18
n/a
0.023
n/a
6.2
n/a
6.3
n/a
6.2
n/a
0.02
n/a
548
n/a
558
n/a
553
n/a
1.9
n/a
61
n/a
76
n/a
70
n/a
2.3
n/a
166
n/a
183
n/a
176
n/a
3.0
n/a
405
n/a
454
n/a
432
n/a
11.7
n/a
1061
n/a
1095
n/a
1072
n/a
6.3
n/a
5
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
10:55 - 12:35
14.1
18.1
14.6
0.32
3.35
3.41
3.38
0.009
46.7
47.4
47.2
0.17
452
453
452
0.1
4+5+6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
-76-
A3. CHP-unit #3 (spring 2011)
74100741-GCS 12-1002
-77-
A3. CHP-unit #3 (winter 2011)
74100741-GCS 12-1002
-78-
74100741-GCS 12-1002
A4. CHP-unit #4 (spring 2011)
Test location & date
Location
City
Date
***
***
19 April 2011
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks:
hrs
hrs
hrs
***
***
***
2008
Ápril 2009
6658
6079
7600
· In December 2010 anti-polishing liners and pistons w ere installed w .
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
1)
unknow n effect on crevice volume.
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
Fuel gas characteristics
Type
Sample time
hh:mm
Lower heating value
kJ/m3o
-
***
***
***
2009
---
mm
mm
rpm
kW
bar
o
BTDC
Natural gas
11:30
32570
Vee-12
Open chamber
170
190
11.9
1500
1200
19.3 1)
25.0
Assumption: 96% generator efficiency
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
Measured energy flows and electric efficiency
Measurement period
hh:mm
11:45 - 13:15
Fuel gas consumption
m 3o
488
Measurement duration
mm:ss
89:39.96
326.5
Fuel gas flow
m3o/h
Fuel gas consumption
kW
2954.3
Electricity production (gross)
kWh
1800
Measurement duration
mm:ss
89:14.45
Electricity output (gross)
kW
1210.2
Efficiency (LHV-based)
%
41.0
14:00 - 15:30
496
90:59.90
327.0
2958.8
1825
90:30.90
1209.7
40.9
Measured gas engine process conditions
Measurement period
hh:mm
11:40 - 13:20
o
Combustion air temperature
C
26.0
Intake manifold pressure
bara
3.79
o
Intake manifold temperature
C
48.9
o
C
444
Exhaust gas temperature
13:55 - 15:35
25.5
3.79
48.8
444
hrs
hrs
hrs
hrs
-
6832
2581
-------
Measured gross electric power output variation (relative to actual gross electric power output)
20
15
2.5
Top-top variation
2.0
RMS variation
1.5
10
1.0
5
0.5
0
11:00
A4. L
11:30
12:00
12:30
13:00
13:30
Time (hh:mm)
14:00
14:30
15:00
15:30
0.0
16:00
RMS (%)
Top-top (%)
25
-79-
74100741-GCS 12-1002
A4. CHP-unit #4 (winter 2011)
Test location & date
Location
City
Date
Fuel gas characteristics
Type
***
***
Sample time
hh:mm
21 December 2011 Lower heating value
kJ/m3o
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks:
hrs
hrs
hrs
***
***
***
2008
Ápril 2009
9253
9224
10724
· In December 2010 anti-polishing liners and pistons w ere installed w .
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
1)
unknow n effect on crevice volume.
mm
mm
rpm
kW
bar
o
BTDC
Natural gas
11:15
32270
Vee-12
Open chamber
170
190
11.9
1500
1200
19.3 1)
25.0
Assumption: 96% generator efficiency
· Tw o misfire events during catalyst-out measurement.
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
***
***
***
2009
---
Measured energy flows and electric efficiency
Measurement period
hh:mm
11:45 - 13:15
Fuel gas consumption
m 3o
497
Measurement duration
mm:ss
89:40.11
332.6
Fuel gas flow
m3o/h
Fuel gas consumption
kW
2981.0
Electricity production (gross)
kWh
1815
Measurement duration
mm:ss
89:34.25
Electricity output (gross)
kW
1215.8
Efficiency (LHV-based)
%
40.8
13:55 - 15:25
503
91:00.06
331.6
2972.8
1845
91:03.00
1215.8
40.9
Measured gas engine process conditions
Measurement period
hh:mm
11:40 - 13:20
o
Combustion air temperature
C
30.7
Intake manifold pressure
bara
3.79
o
Intake manifold temperature
C
45.1
o
C
440
Exhaust gas temperature
13:50 - 15:30
31.3
3.81
46.7
440
hrs
hrs
hrs
hrs
-
9522
3979
-------
Measured gross electric power output variation (relative to actual gross electric power output)
25
15
2.0
RMS variation
1.5
10
1.0
5
0.5
0
11:00
11:30
12:00
12:30
13:00
13:30
Time (hh:mm)
14:00
14:30
15:00
15:30
0.0
16:00
RMS (%)
Top-top (%)
20
2.5
Top-top variation
-80-
74100741-GCS 12-1002
A4. CHP-unit #4 (spring 2011)
Emission data
Start
Stop
hh:mm
hh:mm
1
11:45
12:15
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
2
12:15
12:45
Test series
3
4
12:45
14:00
13:15
14:30
Exhaust gas sampling
5
14:30
15:00
Engine-out
Catalyst-out
n/a
post
on
on
to chimney
to chimney
Atmospheric conditions
1017
1017
1017
1017
23
23
24
23
36
35
32
35
Measured emissions
6
15:00
15:30
mbar
o
C
%
1018
23
36
%-v (dry)
9.15
9.16
9.20
9.11
9.09
9.10
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
6.40
625
87
210
6.40
623
85
209
6.40
621
83
203
6.40
<1
3
4
6.40
<1
3
5
6.40
<1
3
5
CH4
ppm-v (dry)
1809
1809
1812
1808
1807
1808
Cx Hy (as C3H8)
ppm-v (wet)
668
657
664
667
Combustion stoichiometry
653
651
%-v (dry)
-
8.81
1.66
8.82
8.86
8.78
1.66
1.67
1.66
Calculated emissions (dry)
8.76
1.66
8.77
1.66
CO
mg/m3o @ 3 %-v O2
1188
1186
1186
<2
<2
<2
NO as NO2
mg/m3o @ 3 %-v O2
271
265
260
8
9
10
NOx as NO2
mg/m3o @ 3 %-v O2
655
652
636
13
15
17
CH4
mg/m3o @ 3 %-v O2
1965
1966
1976
1957
1953
1955
1852
1841
O2
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
3
1017
22
42
Cx Hy as C
mg/m
@ 3 %-v O2
1855
1826
1799
1793
Cx Hy as CH4
mg/m3o @ 3 %-v O2
2473
2391
CO
NO as NO2
g/GJ
g/GJ
336
77
2435
2469
2454
2398
Calculated specific emissions
336
336
<1
<1
75
74
2
3
NOx as NO2
g/GJ
185
185
180
4
4
5
CH4
g/GJ
556
557
560
554
553
554
Cx Hy as C
g/GJ
525
517
524
521
509
Cx Hy as CH4
g/GJ
700
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
2.8
13.1
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n.a.
11.8
n.a.
11.8
m3o/h
4580
---
Notes:
1)
o
689
699
695
679
Calculated hydrocarbon slip
2.8
2.8
2.8
2.8
12.9
13.1
13.0
12.7
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n.a.
11.8
--326.8
<1
3
508
677
2.8
12.6
48
11.5
49
11.5
49
11.5
---
---
---
m 3o/h.
-81-
74100741-GCS 12-1002
A4. CHP-unit #4 (winter 2011)
Emission data
Start
Stop
hh:mm
hh:mm
1
11:45
12:15
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
2
12:15
12:45
Test series
3
4
12:45
13:55
13:15
14:25
Exhaust gas sampling
5
14:25
14:55
Engine-out
Catalyst-out
n/a
post
on
on
to chimney
to chimney
Atmospheric conditions
1016
1016
1016
1016
7
7
7
7
94
94
95
95
Measured emissions
6
14:55
15:25
mbar
o
C
%
1016
7
93
%-v (dry)
9.20
9.20
9.19
9.17
9.18
9.22
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
6.30
577
60
193
6.30
579
62
196
6.30
582
64
199
6.40
<1
6
12
6.40
<1
6
12
6.30
<1
6
12
CH4
ppm-v (dry)
1952
1946
1934
1919
1922
1924
Cx Hy (as C3H8)
ppm-v (wet)
739
739
719
720
Combustion stoichiometry
708
710
%-v (dry)
-
8.84
1.67
8.84
8.83
8.82
1.67
1.66
1.66
Calculated emissions (dry)
8.83
1.66
8.87
1.67
CO
mg/m3o @ 3 %-v O2
1102
1106
1110
<2
<2
<2
NO as NO2
mg/m3o @ 3 %-v O2
188
194
200
19
19
19
NOx as NO2
mg/m3o @ 3 %-v O2
604
614
623
38
37
38
CH4
mg/m3o @ 3 %-v O2
2129
2123
2108
2088
2093
2102
Cx Hy as C
mg/m3o @ 3 %-v O2
2058
2058
2001
1898
1870
1905
Cx Hy as CH4
mg/m3o @ 3 %-v O2
2745
2539
CO
NO as NO2
g/GJ
g/GJ
312
53
2745
2668
2531
2493
Calculated specific emissions
313
314
<1
<1
55
57
5
5
NOx as NO2
g/GJ
171
174
176
11
10
11
CH4
g/GJ
603
601
597
591
593
595
Cx Hy as C
g/GJ
583
583
567
538
530
Cx Hy as CH4
g/GJ
777
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
3.0
14.5
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n.a.
11.7
n.a.
11.7
m3o/h
4642
---
O2
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
Notes:
1)
777
756
717
706
Calculated hydrocarbon slip
3.0
3.0
3.0
3.0
14.5
14.1
13.4
13.2
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n.a.
11.7
--332.1
1016
7
95
<1
6
539
719
3.0
13.4
39
6.9
39
7.0
42
8.2
4624
---
---
m 3o/h.
-82-
74100741-GCS 12-1002
A4. CHP-unit #4 (spring 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
11:45
12:15
9.10
9.20
9.15
0.022
6.3
6.4
6.4
0.02
620
630
625
2.4
78
98
87
4.0
197
224
210
5.3
624
698
668
15.3
1783
1832
1809
9.3
2
12:15
12:45
9.10
9.21
9.16
0.026
6.3
6.4
6.4
0.02
617
629
623
2.6
75
95
85
3.7
195
221
209
5.0
612
679
657
12.7
1782
1838
1809
9.3
Test series
3
4
12:45
14:00
13:15
14:30
9.15
9.05
9.24
9.18
9.20
9.11
0.024
0.028
6.3
6.4
6.4
6.5
6.4
6.4
0.02
0.02
617
-1
627
0
621
-1
2.0
0.2
75
1.4
94
3.6
83
2.5
3.5
0.48
192
2.4
214
6.2
203
4.2
4.3
0.85
623
630
687
689
664
667
12.5
9.9
1793
1784
1830
1832
1812
1808
8.6
10.8
5
14:30
15:00
9.05
9.13
9.09
0.021
6.4
6.5
6.4
0.02
-2
-1
-1
0.2
1.9
4.7
2.9
0.57
3.1
7.8
4.8
0.99
617
678
653
10.6
1784
1836
1807
10.8
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
11:40 - 13:20
22.9
31.4
26.0
1.80
3.75
3.83
3.79
0.013
48.6
49.1
48.9
0.10
443
445
444
0.4
4+5+6
13:55 - 15:35
23.0
27.9
25.5
0.86
3.75
3.83
3.79
0.014
48.7
49.0
48.8
0.06
443
445
444
0.4
6
15:00
15:30
9.05
9.14
9.10
0.023
6.4
6.4
6.4
0.02
-2
-1
-1
0.2
2.4
4.4
3.2
0.38
4.1
7.3
5.4
0.67
606
670
651
10.0
1783
1828
1808
8.5
-83-
74100741-GCS 12-1002
A4. CHP-unit #4 (winter 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
11:45
12:15
9.15
9.24
9.20
0.024
6.3
6.3
6.3
0.02
572
582
577
2.2
49
71
60
4.6
175
210
193
7.0
691
763
739
12.5
1928
1980
1952
10.5
2
12:15
12:45
9.16
9.24
9.20
0.022
6.3
6.3
6.3
0.02
575
582
579
1.7
50
76
62
4.9
180
217
196
7.3
693
768
739
16.7
1914
1977
1946
9.8
Test series
3
4
12:45
13:55
13:15
14:25
9.14
9.13
9.23
9.20
9.19
9.17
0.024
0.022
6.3
6.3
6.4
6.4
6.3
6.4
0.02
0.02
577
-2
586
-1
582
-2
2.6
0.2
53
4.7
74
7.8
64
6.1
4.7
0.66
182
9.4
216
15.4
199
12.1
7.3
1.29
700
685
749
746
719
720
19.4
13.4
1912
1902
1957
1942
1934
1919
11.9
7.7
5
14:25
14:55
9.13
9.24
9.18
0.025
6.3
6.4
6.4
0.02
-2
-1
-2
0.1
4.7
7.9
6.0
0.67
9.3
15.3
11.8
1.26
672
733
708
12.1
1896
1973
1922
10.7
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
11:40 - 13:20
25.1
34.5
30.7
1.50
3.75
3.84
3.79
0.014
44.5
45.8
45.1
0.19
439
441
440
0.3
4+5+6
13:50 - 15:30
25.3
35.0
31.3
1.52
3.75
3.89
3.81
0.023
45.2
49.7
46.7
1.62
439
441
440
0.5
6
14:55
15:25
9.16
9.27
9.22
0.025
6.3
6.4
6.3
0.02
-2
-1
-2
0.2
4.3
7.8
6.2
0.74
8.5
15.4
12.2
1.41
694
733
710
12.2
1903
1948
1924
9.1
-84-
A4. CHP-unit #4 (spring 2011)
74100741-GCS 12-1002
-85-
A4. CHP-unit #4 (winter 2011)
74100741-GCS 12-1002
-86-
74100741-GCS 12-1002
A5. CHP-unit #5 (spring 2011)
Test location & date
Location
City
Date
***
***
20 April 2011
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks:
hrs
hrs
hrs
***
***
***
2008
December 2008
9128
8153
9153
· Next maintenance scheduled for day after measurement.
· Occasional misfire.
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
Fuel gas characteristics
Type
Sample time
hh:mm
Lower heating value
kJ/m3o
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
mm
mm
rpm
kW
bar
o
BTDC
Vee-16
Open chamber
159
190
12.7
1500
1400
19.3 1)
20.0 2)
1)
Assumption: 96% generator efficiency
2)
Cont. adjustment per cyl in c. 19.7o to 20.4o range (occas. 14.0o)
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
n/a
n/a
n/a
n/a
n/a
Natural gas
11:25
32460
Measured energy flows and electric efficiency
Measurement period
hh:mm
13:15 - 13:55
Fuel gas consumption
m 3o
229.8
Measurement duration
mm:ss
36:53.23
373.7
Fuel gas flow
m3o/h
Fuel gas consumption
kW
3369.8
Electricity production (gross)
kWh
843
Measurement duration
mm:ss
36:03.81
Electricity output (gross)
kW
1402.5
Efficiency (LHV-based)
%
41.6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
Measured gas engine process conditions
Measurement period
hh:mm
11:40 - 13:20
o
Combustion air temperature
C
25.4
Intake manifold pressure
bara
3.46
o
Intake manifold temperature
C
42.6
o
C
451
Exhaust gas temperature
n/a
n/a
n/a
n/a
n/a
hrs
hrs
hrs
hrs
-
n/a
n/a
n/a
n/a
n/a
Measured gross electric power output variation (relative to actual gross electric power output)
3.0
25
Top-top variation
2.5
20
RMS variation
2.0
15
1.5
10
1.0
5
0.5
0
11:00
11:30
12:00
12:30
13:00
13:30
Time (hh:mm)
14:00
14:30
15:00
15:30
0.0
16:00
RMS (%)
Top-top (%)
30
-87-
74100741-GCS 12-1002
A5. CHP-unit #5 (winter 2011)
Test location & date
Location
City
Date
Fuel gas characteristics
Type
***
***
Sample time
hh:mm
22 December 2011 Lower heating value
kJ/m3o
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks:
hrs
hrs
hrs
***
***
***
2008
December 2008
11862
11187
12187
· Repeated misfire.
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
mm
mm
rpm
kW
bar
o
BTDC
Vee-16
Open chamber
159
190
12.7
1500
1400
19.3 1)
21.0 2)
1)
Assumption: 96% generator efficiency
2)
Cont. adjustment per cyl in c. 19.6o to 20.5o range (occas. 17.8o)
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
n/a
n/a
n/a
n/a
n/a
Natural gas
11:40
32420
Measured energy flows and electric efficiency
Measurement period
hh:mm
11:45 - 13:15
Fuel gas consumption
m 3o
574.3
Measurement duration
mm:ss
90:02.37
382.7
Fuel gas flow
m3o/h
Fuel gas consumption
kW
3446.6
Electricity production (gross)
kWh
2076
Measurement duration
mm:ss
89:09.17
Electricity output (gross)
kW
1397.2
Efficiency (LHV-based)
%
40.5
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
Measured gas engine process conditions
Measurement period
hh:mm
11:40 - 13:20
o
Combustion air temperature
C
11.0
Intake manifold pressure
bara
3.65
o
Intake manifold temperature
C
43.1
o
C
440
Exhaust gas temperature
n/a
n/a
n/a
n/a
n/a
hrs
hrs
hrs
hrs
-
n/a
n/a
n/a
n/a
n/a
Measured gross electric power output variation (relative to actual gross electric power output)
Top-top (%)
25
Top-top variation
2.5
20
RMS variation
2.0
15
1.5
10
1.0
5
0.5
0
11:00
11:30
12:00
12:30
13:00
13:30
Time (hh:mm)
14:00
14:30
15:00
15:30
0.0
16:00
RMS (%)
3.0
30
-88-
74100741-GCS 12-1002
A5. CHP-unit #5 (spring 2011)
Emission data
Start
Stop
hh:mm
hh:mm
1
11:45
12:15
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
2
12:15
12:45
Test series
3
4
12:45
n/a
13:15
n/a
Exhaust gas sampling
Engine-out
pre
n/a
to chimney
Atmospheric conditions
1018
1018
n/a
23
23
n/a
29
28
n/a
Measured emissions
mbar
o
C
%
1018
24
29
%-v (dry)
8.78
8.77
8.77
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
6.60
524
568
673
6.70
526
580
692
6.60
525
584
697
CH4
ppm-v (dry)
1058
1050
1043
Cx Hy (as C3H8)
ppm-v (wet)
364
367
367
n/a
Combustion stoichiometry
%-v (dry)
-
8.60
1.64
8.60
8.60
n/a
1.63
1.63
n/a
Calculated emissions (dry)
O2
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
5
n/a
n/a
6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
CO
mg/m3o @ 3 %-v O2
966
969
967
n/a
n/a
n/a
NO as NO2
mg/m3o @ 3 %-v O2
1717
1752
1764
n/a
n/a
n/a
NOx as NO2
mg/m3o @ 3 %-v O2
2035
2091
2106
n/a
n/a
n/a
CH4
mg/m3o @ 3 %-v O2
1114
1105
1097
n/a
n/a
n/a
990
990
3
Cx Hy as C
mg/m
@ 3 %-v O2
982
Cx Hy as CH4
mg/m3o @ 3 %-v O2
1310
CO
NO as NO2
g/GJ
g/GJ
274
487
1320
1319
Calculated specific
275
274
496
500
NOx as NO2
g/GJ
577
592
597
CH4
g/GJ
316
313
Cx Hy as C
g/GJ
278
281
Cx Hy as CH4
g/GJ
371
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
1.6
6.9
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n.a.
12.0
n.a.
12.0
m3o/h
5060
---
Notes:
1)
o
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
311
n/a
n/a
n/a
280
n/a
n/a
n/a
emissions
n/a
n/a
374
374
n/a
n/a
Calculated hydrocarbon slip
1.6
1.6
n/a
n/a
7.0
7.0
n/a
n/a
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n.a.
12.0
--373.7
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
---
---
---
m 3o/h.
-89-
74100741-GCS 12-1002
A5. CHP-unit #5 (winter 2011)
Emission data
Start
Stop
hh:mm
hh:mm
1
11:45
12:15
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
2
12:15
12:45
Test series
3
4
12:45
n/a
13:15
n/a
Exhaust gas sampling
Engine-out
pre
n/a
to chimney
Atmospheric conditions
1021
1021
n/a
10
10
n/a
90
91
n/a
Measured emissions
mbar
o
C
%
1021
10
91
%-v (dry)
9.40
9.42
9.40
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
6.19
568
159
269
6.20
567
149
259
6.21
568
152
264
CH4
ppm-v (dry)
1354
1363
1358
Cx Hy (as C3H8)
ppm-v (wet)
536
534
533
n/a
Combustion stoichiometry
%-v (dry)
-
9.15
1.71
CO
mg/m3o @ 3 %-v O2
NO as NO2
mg/m3o @ 3 %-v O2
NOx as NO2
5
n/a
n/a
6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
9.17
9.15
n/a
1.71
1.71
n/a
Calculated emissions (dry)
n/a
n/a
n/a
n/a
1103
1103
1103
n/a
n/a
n/a
507
476
484
n/a
n/a
n/a
mg/m3o @ 3 %-v O2
857
827
841
n/a
n/a
n/a
CH4
mg/m3o @ 3 %-v O2
1502
1515
1507
n/a
n/a
n/a
Cx Hy as C
mg/m3o @ 3 %-v O2
1519
1516
1511
n/a
n/a
n/a
Cx Hy as CH4
mg/m3o @ 3 %-v O2
2025
n/a
n/a
CO
NO as NO2
g/GJ
g/GJ
312
143
2021
2015
Calculated specific
312
312
135
137
n/a
n/a
n/a
n/a
NOx as NO2
g/GJ
243
234
238
n/a
n/a
n/a
CH4
g/GJ
425
429
426
n/a
n/a
n/a
Cx Hy as C
g/GJ
430
429
428
n/a
n/a
Cx Hy as CH4
g/GJ
573
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
2.1
10.7
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n.a.
11.7
n.a.
11.7
m3o/h
5464
---
O2
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
Notes:
1)
n/a
emissions
n/a
n/a
572
570
n/a
n/a
Calculated hydrocarbon slip
2.1
2.1
n/a
n/a
10.7
10.6
n/a
n/a
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n.a.
11.7
--382.7
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
---
---
---
m 3o/h.
-90-
74100741-GCS 12-1002
A5. CHP-unit #5 (spring 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
11:45
12:15
8.73
8.82
8.78
0.023
6.5
6.7
6.6
0.03
520
527
524
1.6
526
610
568
17.6
627
721
673
19.2
353
382
364
6.5
1042
1078
1058
7.1
2
12:15
12:45
8.73
8.81
8.77
0.020
6.6
6.7
6.7
0.02
522
528
526
1.7
532
633
580
19.5
641
751
692
20.8
339
388
367
7.1
1030
1083
1050
8.9
Test series
3
4
12:45
n/a
13:15
n/a
8.73
n/a
8.81
n/a
8.77
n/a
0.019
n/a
6.6
n/a
6.7
n/a
6.6
n/a
0.02
n/a
522
n/a
528
n/a
525
n/a
1.5
n/a
528
n/a
629
n/a
584
n/a
21.2
n/a
638
n/a
747
n/a
697
n/a
22.6
n/a
345
n/a
386
n/a
367
n/a
7.2
n/a
1026
n/a
1064
n/a
1043
n/a
6.6
n/a
5
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
11:40 - 13:20
23.7
28.0
25.4
0.73
3.42
3.52
3.46
0.016
42.1
43.1
42.6
0.22
450
453
451
0.6
4+5+6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
-91-
74100741-GCS 12-1002
A5. CHP-unit #5 (winter 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
11:45
12:15
9.36
9.44
9.40
0.024
6.1
6.2
6.2
0.02
563
572
568
1.9
140
183
159
7.1
247
297
269
8.1
512
558
536
11.4
1337
1403
1354
8.3
2
12:15
12:45
9.37
9.46
9.42
0.022
6.2
6.2
6.2
0.02
562
570
567
1.7
135
166
149
6.3
243
280
259
7.4
502
562
534
12.9
1346
1390
1363
7.7
Test series
3
4
12:45
n/a
13:15
n/a
9.35
n/a
9.44
n/a
9.40
n/a
0.024
n/a
6.2
n/a
6.3
n/a
6.2
n/a
0.02
n/a
563
n/a
573
n/a
568
n/a
2.0
n/a
138
n/a
173
n/a
152
n/a
8.0
n/a
245
n/a
288
n/a
264
n/a
9.2
n/a
504
n/a
568
n/a
533
n/a
13.8
n/a
1337
n/a
1384
n/a
1358
n/a
9.0
n/a
5
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
11:40 - 13:20
10.6
11.7
11.0
0.17
3.57
3.73
3.65
0.025
40.9
45.1
43.1
0.30
439
441
440
0.3
4+5+6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
-92-
A5. CHP-unit #5 (spring 2011)
74100741-GCS 12-1002
-93-
A5. CHP-unit #5 (winter 2011)
74100741-GCS 12-1002
-94-
74100741-GCS 12-1002
A6. CHP-unit #6 (spring 2011)
Test location & date
Location
Town
Date
***
***
27 April 2011
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks:
hrs
hrs
hrs
***
***
***
2006
August 2006
24397
24100
25100
· During last maintenance 'test' spark plugs w ere installed.
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
***
----2006
September 2006
Fuel gas characteristics
Type
Sample time
hh:mm
Lower heating value
kJ/m3o
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
Natural gas
12:30
32550
Vee-12
Prechamber/port injection
mm
350
mm
400
13.0
rpm
750
kW
5120
bar
18.5 1)
o
BTDC
10.8 2)
1)
Assumption: 96% generator efficiency
2)
Fixed per-cylinder retard betw een 0.0o and 0.8o
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
Measured energy flows and electric efficiency
Measurement period
hh:mm
12:45 - 14:15
2028
Fuel gas consumption
m 3o
Measurement duration
mm:ss
94:32.98
Fuel gas flow
m3o/h
1286.9
Fuel gas consumption
kW
11636.1
Electricity production (gross)
kWh
7907.2
Measurement duration
mm:ss
92:12.69
Electricity output (gross)
kW
5145.0
Efficiency (LHV-based)
%
44.2
14:45 - 16:15
1936
90:03.10
1289.9
11663.1
7944.0
92:38.18
5145.3
44.1
Measured gas engine process conditions
Measurement period
hh:mm
12:40 - 14:20
o
C
32.1
Combustion air temperature
Intake manifold pressure
bara
3.75
o
Intake manifold temperature
C
51.4
o
Exhaust gas temperature
C
386
14:40 - 16:20
32.1
3.77
51.6
384
hrs
hrs
hrs
hrs
-
----24192
-----
Measured gross electric power output variation (relative to actual gross electric power output)
25
15
51%
2.5
2.0
RMS variation
1.5
10
1.0
5
0.5
0
12:00
12:30
13:00
13:30
14:00
14:30
Time (hh:mm)
15:00
15:30
16:00
16:30
0.0
17:00
RMS (%)
Top-top (%)
20
•
Top-top variation
-95-
74100741-GCS 12-1002
A6. CHP-unit #6 (winter 2011)
Test location & date
Location
Town
Date
Fuel gas characteristics
Type
***
***
Sample time
hh:mm
20 December 2011 Lower heating value
kJ/m3o
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks:
hrs
hrs
hrs
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
***
***
***
2006
August 2006
27620
27273
28273
· 'Test' spark plugs w ere still installed.
· Just prior to tests, all cylinder heads w ere replaced (w /o cleaning of
pistons and cylinder liners) and ign. timing and λ w ere readjusted.
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
***
------2006
September 2006
Natural gas
12:35
31990
Vee-12
Prechamber/port injection
mm
350
mm
400
13.0
rpm
750
kW
5120
bar
18.5 1)
o
BTDC
12.3 2)
1)
Assumption: 96% generator efficiency
2)
Fixed per-cylinder retard betw een -0.50o and 0.80o
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
Measured energy flows and electric efficiency
Measurement period
hh:mm
12:45 - 14:15
1906
Fuel gas consumption
m 3o
Measurement duration
mm:ss
89:33.01
Fuel gas flow
m3o/h
1277.0
Fuel gas consumption
kW
11348.0
Electricity production (gross)
kWh
7644
Measurement duration
mm:ss
89:18.18
Electricity output (gross)
kW
5135.8
Efficiency (LHV-based)
%
45.3
14:45 - 16:15
1914
89:58.80
1276.3
11341.2
7647.2
89:20.17
5136.0
45.3
Measured gas engine process conditions
Measurement period
hh:mm
12:40 - 14:20
o
C
32.9
Combustion air temperature
Intake manifold pressure
bara
3.47
o
Intake manifold temperature
C
50.8
o
Exhaust gas temperature
C
404
14:40 - 16:20
33.2
3.47
50.2
404
hrs
hrs
hrs
hrs
-
----------------
Measured gross electric power output variation (relative to actual gross electric power output)
20
15
2.5
Top-top variation
2.0
RMS variation
1.5
10
1.0
5
0.5
0
12:00
12:30
13:00
13:30
14:00
14:30
Time (hh:mm)
15:00
15:30
16:00
16:30
0.0
17:00
RMS (%)
Top-top (%)
25
-96-
74100741-GCS 12-1002
A6. CHP-unit #6 (spring 2011)
Emission data
Start
Stop
hh:mm
hh:mm
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
mbar
o
C
%
1
12:45
13:15
2
13:15
13:45
Test series
3
4
13:45
14:45
14:15
15:15
Exhaust gas sampling
5
15:15
15:45
6
15:45
16:15
Engine-out
Catalyst-out
n/a
post
on
on
to greenhouse
to greenhouse
Atmospheric conditions
1025
1025
1024
1024
1024
1024
16
16
15
15
15
14
52
60
63
63
64
65
Measured emissions
%-v (dry)
11.12
11.13
11.14
11.11
11.11
11.12
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
5.20
357
41
58
5.20
370
38
54
5.20
373
37
53
5.30
<1
10
18
5.30
<1
11
19
5.30
<1
11
18
CH4
ppm-v (dry)
1347
1378
1383
1367
1377
1386
Cx Hy (as C3H8)
ppm-v (wet)
502
506
503
494
Combustion stoichiometry
501
507
%-v (dry)
-
10.87
1.98
10.87
10.88
10.87
1.98
1.98
1.98
Calculated emissions (dry)
10.87
1.98
10.88
1.98
CO
mg/m3o @ 3 %-v O2
815
845
853
<2
<2
<2
NO as NO2
mg/m3o @ 3 %-v O2
152
142
140
39
41
40
NOx as NO2
mg/m3o @ 3 %-v O2
216
203
198
67
70
69
CH4
mg/m3o @ 3 %-v O2
1756
1798
1807
1780
1794
1807
Cx Hy as C
mg/m3o @ 3 %-v O2
1643
1658
1650
1616
1639
1660
Cx Hy as CH4
mg/m3o @ 3 %-v O2
2191
2213
CO
NO as NO2
g/GJ
g/GJ
231
43
2211
2200
2154
2185
Calculated specific emissions
239
241
<1
<1
40
39
11
12
NOx as NO2
g/GJ
61
O2
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
57
56
19
20
<1
11
19
CH4
g/GJ
497
509
511
504
508
511
Cx Hy as C
g/GJ
465
469
467
457
464
470
Cx Hy as CH4
g/GJ
620
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
2.5
11.6
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n.a.
10.2
n.a.
10.2
m3o/h
21670
---
Notes:
1)
626
623
610
618
Calculated hydrocarbon slip
2.5
2.6
2.5
2.5
11.7
11.6
11.4
11.5
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n.a.
10.2
--1288
626
2.6
11.7
52
10.2
52
10.2
52
10.2
---
---
---
m 3o/h.
-97-
74100741-GCS 12-1002
A6. CHP-unit #6 (winter 2011)
Emission data
Start
Stop
hh:mm
hh:mm
1
12:45
13:15
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
2
13:15
13:45
Test series
3
4
13:45
14:45
14:15
15:15
Exhaust gas sampling
5
15:15
15:45
Engine-out
Catalyst-out
n/a
post
on
on
to chimney
to chimney
Atmospheric conditions
1008
1009
1010
1010
8
8
8
8
72
74
77
77
Measured emissions
6
15:45
16:15
mbar
o
C
%
1008
9
68
%-v (dry)
10.65
10.67
10.67
10.65
10.61
10.61
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
5.50
277
162
187
5.50
281
157
183
5.50
283
157
184
5.50
<1
11
16
5.50
<1
9
14
5.50
<1
9
13
CH4
ppm-v (dry)
1089
1102
1109
1103
1105
1104
Cx Hy (as C3H8)
ppm-v (wet)
418
424
424
425
Combustion stoichiometry
423
421
%-v (dry)
-
10.46
1.91
10.47
10.47
10.46
1.91
1.91
1.91
Calculated emissions (dry)
10.42
1.90
10.42
1.90
CO
mg/m3o @ 3 %-v O2
603
613
618
<2
<2
<2
NO as NO2
mg/m3o @ 3 %-v O2
579
562
562
38
33
31
NOx as NO2
mg/m3o @ 3 %-v O2
668
655
659
58
51
47
CH4
mg/m3o @ 3 %-v O2
1355
1374
1383
1372
1370
1368
Cx Hy as C
mg/m3o @ 3 %-v O2
1306
1329
1328
1330
1319
1314
Cx Hy as CH4
mg/m3o @ 3 %-v O2
1742
1752
CO
NO as NO2
g/GJ
g/GJ
171
164
1772
1770
1773
1759
Calculated specific emissions
174
175
<1
<1
159
159
11
9
NOx as NO2
g/GJ
189
186
O2
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
187
17
14
1011
8
77
<1
9
13
CH4
g/GJ
384
389
392
389
388
388
Cx Hy as C
g/GJ
370
377
376
377
374
373
Cx Hy as CH4
g/GJ
494
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
1.9
9.2
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n.a.
10.3
n.a.
10.3
m3o/h
20204
---
Notes:
1)
502
502
503
499
Calculated hydrocarbon slip
1.9
2.0
1.9
1.9
9.4
9.4
9.4
9.3
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n.a.
10.3
--1277
497
1.9
9.3
51
10.4
50
10.4
50
10.4
20115
---
---
m 3o/h.
-98-
74100741-GCS 12-1002
A6. CHP-unit #6 (spring 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
12:45
13:15
11.03
11.19
11.12
0.031
5.2
5.3
5.2
0.02
346
370
357
6.4
36
47
41
2.3
52
65
58
2.6
479
522
502
9.0
1310
1388
1347
17.6
2
13:15
13:45
11.05
11.19
11.13
0.032
5.2
5.3
5.2
0.02
362
378
370
4.2
34
43
38
1.9
49
59
54
2.1
481
537
506
9.4
1338
1428
1378
17.0
Test series
3
4
13:45
14:45
14:15
15:15
11.07
11.04
11.22
11.19
11.14
11.11
0.033
0.029
5.2
5.3
5.3
5.3
5.2
5.3
0.02
0.02
360
2
381
3
373
2
4.7
0.3
33
9.8
43
10.9
37
10.4
1.8
0.24
47
16.7
59
18.6
53
17.8
2.1
0.42
480
449
526
515
503
494
8.8
12.1
1339
1328
1432
1402
1383
1367
14.2
15.5
5
15:15
15:45
11.05
11.19
11.11
0.033
5.3
5.4
5.3
0.02
2
3
2
0.3
10.3
11.4
10.9
0.27
17.7
19.6
18.6
0.48
467
525
501
9.3
1329
1417
1377
18.6
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
12:40 - 14:20
30.4
34.2
32.1
0.61
3.71
3.80
3.75
0.015
50.8
52.0
51.4
0.20
383
388
386
0.8
4+5+6
14:40 - 16:20
30.4
33.7
32.1
0.62
3.73
3.81
3.77
0.013
51.0
52.3
51.6
0.20
382
386
384
0.7
6
15:45
16:15
11.04
11.19
11.12
0.034
5.3
5.3
5.3
0.02
2
3
2
0.3
9.8
11.2
10.7
0.33
17.0
19.5
18.4
0.54
481
535
507
10.2
1335
1440
1386
17.9
-99-
74100741-GCS 12-1002
A6. CHP-unit #6 (winter 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
12:45
13:15
10.58
10.69
10.65
0.024
5.4
5.5
5.5
0.02
274
281
277
1.6
149
175
162
5.0
173
201
187
5.6
392
439
418
11.8
1070
1108
1089
6.2
2
13:15
13:45
10.58
10.75
10.67
0.034
5.4
5.5
5.5
0.02
276
286
281
1.8
143
178
157
7.0
167
207
183
8.1
400
443
424
10.7
1082
1118
1102
7.6
Test series
3
4
13:45
14:45
14:15
15:15
10.54
10.58
10.78
10.71
10.67
10.65
0.036
0.031
5.4
5.5
5.5
5.5
5.5
5.5
0.02
0.02
279
0
288
0
283
0
2.9
0.1
133
8.1
178
16.0
157
10.7
7.2
1.81
159
12.4
208
24.2
184
16.3
7.8
2.78
391
389
445
446
424
425
12.2
12.0
1089
1088
1133
1126
1109
1103
10.9
6.5
5
15:15
15:45
10.53
10.67
10.61
0.031
5.5
5.6
5.5
0.02
0
0
0
0.1
7.9
15.2
9.3
1.09
12.2
23.1
14.3
1.70
401
442
423
10.8
1092
1125
1105
5.8
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
12:40 - 14:20
30.6
36.4
32.9
1.01
3.44
3.50
3.47
0.010
49.8
52.0
50.8
0.41
402
407
404
0.8
4+5+6
14:40 - 16:20
31.4
37.0
33.2
0.99
3.44
3.50
3.47
0.009
49.4
51.1
50.2
0.32
403
406
404
0.7
6
15:45
16:15
10.56
10.66
10.61
0.024
5.5
5.6
5.5
0.02
0
0
0
0.2
8.0
12.2
8.7
0.64
12.1
18.7
13.2
0.98
400
442
421
10.9
1085
1125
1104
6.2
-100-
A6. CHP-unit #6 (spring 2011)
74100741-GCS 12-1002
-101-
A6. CHP-unit #6 (winter 2011)
74100741-GCS 12-1002
-102-
74100741-GCS 12-1002
A7. CHP-unit #7 (spring 2011)
Test location & date
Location
Town
Date
***
***
28 April 2011
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks:
hrs
hrs
hrs
***
***
***
2005
November 2005
36445
34814
36814
· All cyl. heads and liners replaced & pistons cleaned at 29536 RH.
· One cylinder-unit replaced at 35868 RH (no cyl. head cleaning).
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
Measured energy flows and
Measurement period
Fuel gas consumption
Measurement duration
Fuel gas flow
Fuel gas consumption
Electricity production (gross)
Measurement duration
Electricity output (gross)
Efficiency (LHV-based)
Fuel gas characteristics
Type
Sample time
hh:mm
Lower heating value
kJ/m3o
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
1)
Vee-12
Open chamber
170
195
13.5
1500
1166
18.3 1)
25.0
Assumption: 96% generator efficiency
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
***
***
-------
mm
mm
rpm
kW
bar
o
BTDC
Natural gas
13:00
32460
electric efficiency
14:10 - 15:40
hh:mm
466.0
m3o
89:32.09
mm:ss
312.3
m3o/h
2815.7
kW
1740
kWh
89:11.68
mm:ss
1170.5
kW
41.6
%
Measured gas engine process conditions
14:05 - 15:45
Measurement period
hh:mm
o
21.3
C
Combustion air temperature
Intake manifold press. LB/RB
bara
3.26
3.28
o
Intake manifold temp. LB/RB
C
46.4
45.6
o
440
Exhaust gas temperature
C
hrs
hrs
hrs
hrs
-
-----------
16:00 - 17:30
463.0
88:41.97
313.2
2824.0
1738
89:06.06
1170.4
41.4
15:55 - 17:35
22.8
3.25
3.27
46.0
45.2
440
Measured gross electric power output variation (relative to actual gross electric power output)
25
15
2.0
RMS variation
1.5
10
1.0
5
0.5
0
13:00
13:30
14:00
14:30
15:00
15:30
Time (hh:mm)
16:00
16:30
17:00
17:30
0.0
18:00
RMS (%)
Top-top (%)
20
2.5
Top-top variation
-103-
74100741-GCS 12-1002
A7. CHP-unit #7 (winter 2011)
Test location & date
Location
Town
Date
Fuel gas characteristics
Type
***
***
hh:mm
Sample time
19 December 2011 Lower heating value
kJ/m3o
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks:
hrs
hrs
hrs
***
***
***
2005
November 2005
40360
38635
40635
· One cylinder-unit replaced at 40010 hrs.
· One single misfire-event.
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
1)
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
Measured energy flows and
Measurement period
Fuel gas consumption
Measurement duration
Fuel gas flow
Fuel gas consumption
Electricity production (gross)
Measurement duration
Electricity output (gross)
Efficiency (LHV-based)
Vee-12
Open chamber
170
195
13.5
1500
1166
18.3 1)
25.0
Assumption: 96% generator efficiency
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
***
***
----------
mm
mm
rpm
kW
bar
o
BTDC
Natural gas
12:15
32290
electric efficiency
12:30 - 14:00
hh:mm
n/a
m3o
n/a
mm:ss
m3o/h
n/a
kW
n/a
kWh
1752.5
mm:ss
89:55.04
1169.4
kW
n.a.
%
hrs
hrs
hrs
hrs
-
----------------
14:45 - 16:15
457.0
86:38.16
316.5
2838.8
1705
87:28.98
1169.4
41.2
Measured gas engine process conditions
12:25 - 14:05
Measurement period
hh:mm
o
15.7
C
Combustion air temperature
Intake manifold press. LB/RB
bara
3.30
3.32
o
Intake manifold temp. LB/RB
C
47.3
45.9
o
Exhaust gas temperature
C
439
14:40 - 16:20
14.7
3.30
3.32
47.1
45.7
439
Measured gross electric power output variation (relative to actual gross electric power output)
• 31%
20
15
2.5
Top-top variation
2.0
RMS variation
1.5
10
1.0
5
0.5
0
12:00
12:30
13:00
13:30
14:00
14:30
Time (hh:mm)
15:00
15:30
16:00
16:30
0.0
17:00
RMS (%)
Top-top (%)
25
-104-
74100741-GCS 12-1002
A7. CHP-unit #7 (spring 2011)
Emission data
Start
Stop
hh:mm
hh:mm
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
mbar
o
C
%
1
14:10
14:40
2
14:40
15:10
Test series
3
4
15:10
16:00
15:40
16:30
Exhaust gas sampling
5
16:30
17:00
6
17:00
17:30
Engine-out
Catalyst-out
n/a
post
on
on
to greenhouse
to greenhouse
Atmospheric conditions
1018
1018
1018
1017
1017
1017
16
17
19
19
19
19
78
70
68
67
62
61
Measured emissions
%-v (dry)
9.39
9.40
9.39
9.34
9.35
9.35
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
6.20
487
177
222
6.20
486
175
219
6.20
486
174
221
6.20
<1
5
8
6.20
<1
5
8
6.20
<1
5
8
CH4
ppm-v (dry)
1064
1065
1067
1054
1051
1050
Cx Hy (as C3H8)
ppm-v (wet)
422
421
421
386
Combustion stoichiometry
386
386
%-v (dry)
-
9.19
1.71
9.20
9.19
9.15
1.71
1.71
1.71
Calculated emissions (dry)
9.16
1.71
9.16
1.71
CO
mg/m3o @ 3 %-v O2
945
944
943
<2
<2
<2
NO as NO2
mg/m3o @ 3 %-v O2
563
558
554
16
16
16
NOx as NO2
mg/m3o @ 3 %-v O2
707
698
703
25
25
25
CH4
mg/m3o @ 3 %-v O2
1180
1182
1183
1164
1161
1160
Cx Hy as C
mg/m3o @ 3 %-v O2
1197
1196
1195
1091
1069
1092
Cx Hy as CH4
mg/m3o @ 3 %-v O2
1597
1455
CO
NO as NO2
g/GJ
g/GJ
267
159
1594
1593
1454
1425
Calculated specific emissions
267
267
<1
<1
158
157
5
5
NOx as NO2
g/GJ
200
197
O2
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
199
7
7
<1
5
7
CH4
g/GJ
334
334
335
329
329
328
Cx Hy as C
g/GJ
339
338
338
309
302
309
Cx Hy as CH4
g/GJ
452
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
1.7
8.4
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n/a
11.9
n/a
11.9
m3o/h
4460
---
Notes:
1)
451
451
411
403
Calculated hydrocarbon slip
1.7
1.7
1.6
1.6
8.4
8.4
7.7
7.5
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n/a
11.9
--312.8
412
1.6
7.7
55
11.9
46
10.0
48
11.9
---
---
---
m 3o/h.
-105-
74100741-GCS 12-1002
A7. CHP-unit #7 (winter 2011)
Emission data
Start
Stop
hh:mm
hh:mm
1
12:30
13:00
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
2
13:00
13:30
Test series
3
4
13:30
14:45
14:00
15:15
Exhaust gas sampling
5
15:15
15:45
Engine-out
Catalyst-out
n/a
post
on
on
to chimney
to chimney
Atmospheric conditions
1016
1016
1015
1015
5
5
4
4
73
73
76
76
Measured emissions
6
15:45
16:15
mbar
o
C
%
1016
5
74
%-v (dry)
9.47
9.48
9.48
9.44
9.44
9.44
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
6.10
504
193
238
6.10
503
195
240
6.10
503
195
241
6.20
<1
4
7
6.20
<1
5
8
6.20
<1
5
8
CH4
ppm-v (dry)
1080
1077
1079
1082
1080
1079
Cx Hy (as C3H8)
ppm-v (wet)
420
421
421
394
Combustion stoichiometry
399
402
%-v (dry)
-
9.27
1.72
9.28
9.28
9.25
1.72
1.72
1.72
Calculated emissions (dry)
9.25
1.72
9.25
1.72
CO
mg/m3o @ 3 %-v O2
985
984
984
<2
<2
<2
NO as NO2
mg/m3o @ 3 %-v O2
619
626
626
13
15
15
NOx as NO2
mg/m3o @ 3 %-v O2
763
770
773
22
25
25
CH4
mg/m3o @ 3 %-v O2
1206
1203
1206
1205
1203
1201
Cx Hy as C
mg/m3o @ 3 %-v O2
1191
1196
1197
1115
1118
1138
Cx Hy as CH4
mg/m3o @ 3 %-v O2
1588
1517
CO
NO as NO2
g/GJ
g/GJ
279
175
1594
1596
1487
1490
Calculated specific emissions
278
278
<1
<1
177
177
4
4
NOx as NO2
g/GJ
216
218
O2
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
219
6
7
1014
4
79
<1
4
7
CH4
g/GJ
341
341
341
341
340
340
Cx Hy as C
g/GJ
337
338
339
316
316
322
Cx Hy as CH4
g/GJ
449
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
1.7
8.4
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n/a
11.3
n/a
11.3
m3o/h
n/a
---
Notes:
1)
451
452
421
422
Calculated hydrocarbon slip
1.7
1.7
1.7
1.7
8.4
8.4
7.9
7.9
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n/a
11.3
--316.5
429
1.7
8.0
53
11.3
47
10.3
53
11.3
4512
---
---
m 3o/h.
-106-
74100741-GCS 12-1002
A7. CHP-unit #7 (spring 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
14:10
14:40
9.34
9.44
9.39
0.023
6.1
6.2
6.2
0.02
483
490
487
1.6
163
185
177
3.9
207
232
222
4.2
403
437
422
7.8
1050
1083
1064
6.1
2
14:40
15:10
9.35
9.45
9.40
0.022
6.1
6.2
6.2
0.02
483
488
486
1.4
164
183
175
3.5
207
229
219
3.8
407
438
421
7.3
1049
1078
1065
5.6
Test series
3
4
15:10
16:00
15:40
16:30
9.34
9.30
9.43
9.38
9.39
9.34
0.023
0.022
6.1
6.2
6.2
6.3
6.2
6.2
0.02
0.02
483
-1
489
0
486
-1
1.6
0.2
164
3.5
181
9.9
174
5.1
3.4
1.27
209
5.4
230
15.2
221
7.9
3.8
1.91
402
362
438
399
421
386
7.6
7.7
1050
1039
1084
1068
1067
1054
5.8
5.1
5
16:30
17:00
9.30
9.38
9.35
0.022
6.2
6.3
6.2
0.02
-2
-1
-1
0.3
3.5
9.4
5.2
1.07
5.4
14.2
7.9
1.61
355
398
386
8.3
1038
1064
1051
5.5
6
17:00
17:30
9.31
9.39
9.35
0.021
6.2
6.3
6.2
0.02
-2
0
-1
0.3
3.5
10.7
5.2
1.22
5.2
16.5
8.0
1.86
365
400
386
7.4
1037
1064
1050
5.2
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold press. LB/RB
Intake manifold temp. LB/RB
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
14:05 - 15:45
19.2
23.6
21.3
0.95
3.22
/
3.24
3.31
/
3.32
3.26
/
3.28
0.011
/
0.011
45.9
/
45.1
46.7
/
45.9
46.4
/
45.6
0.17
/
0.17
439
441
440
0.4
4+5+6
15:55 - 17:35
21.5
24.5
22.8
0.42
3.22
/
3.25
3.28
/
3.30
3.25
/
3.27
0.009
/
0.009
45.4
/
44.6
46.5
/
45.8
46.0
/
45.2
0.23
/
0.24
439
440
440
0.3
-107-
74100741-GCS 12-1002
A7. CHP-unit #7 (winter 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
12:30
13:00
9.43
9.51
9.47
0.021
6.1
6.1
6.1
0.02
500
507
504
1.6
178
205
193
5.4
220
250
238
6.0
395
441
420
11.5
1064
1126
1080
7.9
2
13:00
13:30
9.43
9.52
9.48
0.022
6.1
6.1
6.1
0.02
500
506
503
1.6
183
208
195
5.5
225
256
240
6.5
395
441
421
11.5
1058
1113
1077
7.7
Test series
3
4
13:30
14:45
14:00
15:15
9.44
9.41
9.52
9.48
9.48
9.44
0.022
0.021
6.1
6.1
6.1
6.2
6.1
6.2
0.02
0.02
499
0
507
0
503
0
1.6
0.2
182
3.5
209
5.7
195
4.2
5.4
0.42
226
5.9
258
9.5
241
6.9
6.3
0.68
393
367
440
418
421
394
11.8
12.2
1059
1067
1100
1098
1079
1082
7.3
6.7
5
15:15
15:45
9.40
9.48
9.44
0.021
6.1
6.2
6.2
0.02
-1
0
0
0.2
3.4
21.2
4.7
1.95
5.9
32.7
7.8
3.00
373
420
399
11.5
1063
1097
1080
6.6
6
15:45
16:15
9.39
9.49
9.44
0.023
6.1
6.2
6.2
0.02
0
0
0
0.2
3.6
17.5
4.6
1.55
6.2
28.0
7.7
2.40
367
426
402
12.9
1061
1099
1079
6.9
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold press. LB/RB
Intake manifold temp. LB/RB
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
12:25 - 14:05
13.9
17.6
15.7
0.55
3.25
/
3.27
3.35
/
3.38
3.30
/
3.32
0.018
/
0.016
46.9
/
45.5
47.8
/
46.3
47.3
/
45.9
0.21
/
0.21
438
440
439
0.3
4+5+6
14:40 - 16:20
13.7
16.4
14.7
0.43
3.26
/
3.28
3.36
/
3.37
3.30
/
3.32
0.018
/
0.016
46.8
/
45.4
47.4
/
46.0
47.1
/
45.7
0.10
/
0.10
438
440
439
0.3
-108-
A7. CHP-unit #7 (spring 2011)
74100741-GCS 12-1002
-109-
A7. CHP-unit #7 (winter 2011)
74100741-GCS 12-1002
-110-
74100741-GCS 12-1002
A8. CHP-unit #8 (spring 2011)
Test location & date
Location
City
Date
***
***
04 May 2011
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks:
hrs
hrs
hrs
***
***
***
2006
November 2006
21706
20851
21851
· None
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
***
***
--2006
November 2006
Fuel gas characteristics
Type
Sample time
hh:mm
Lower heating value
kJ/m3o
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
mm
mm
rpm
kW
bar
o
BTDC
Natural gas
11:40
31680
Vee-18
Open chamber
180
200
12.5
1500
2000
18.2 1)
20.0 2 )
1)
Assumption: 96% generator efficiency
2)
Timing per-cyl. in c. 14.5o to 20.0o range + cont. adj. of up to 0.5o
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
Measured energy flows and electric efficiency
Measurement period
hh:mm
11:45 - 13:15
Fuel gas consumption
m 3o
824.5
Measurement duration
mm:ss
89:38.55
551.8
Fuel gas flow
m3o/h
Fuel gas consumption
kW
4856.1
Electricity production (gross)
kWh
2844
Measurement duration
mm:ss
89:59.98
Electricity output (gross)
kW
1896.0
Efficiency (LHV-based)
%
39.0
13:35 - 15:05
821.5
89:18.00
552.0
4857.4
2820
89:15.91
1895.5
39.0
Measured gas engine process conditions
Measurement period
hh:mm
11:40 - 13:20
o
Combustion air temperature
C
20.5
Intake manifold pressure
bara
3.15
o
Intake manifold temperature
C
50.4
o
C
480
Exhaust gas temperature
13:30 - 15:10
19.8
3.15
50.6
480
hrs
hrs
hrs
hrs
-
22286
7041
-------
Measured gross electric power output variation (relative to actual gross electric power output)
2.5
25
15
2.0
RMS variation
1.5
10
1.0
5
0.5
0
11:00
11:30
12:00
12:30
13:00
13:30
Time (hh:mm)
14:00
14:30
15:00
15:30
0.0
16:00
RMS (%)
Top-top (%)
20
Top-top variation
-111-
74100741-GCS 12-1002
A8. CHP-unit #8 (winter 2011)
Test location & date
Location
City
Date
Fuel gas characteristics
Type
***
***
Sample time
hh:mm
30 November 2011 Lower heating value
kJ/m3o
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks:
hrs
hrs
hrs
***
***
***
2006
November 2006
24241
23833
24833
· Three cil. heads and liners replaced & pistons cleaned at 23955 RH.
· Frequent misfire.
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
***
***
--2006
November 2006
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
mm
mm
rpm
kW
bar
o
BTDC
Natural gas
12:00
31700
Vee-18
Open chamber
180
200
12.5
1500
2000
18.2 1)
21.0 2 )
1)
Assumption: 96% generator efficiency
2)
Timing per-cyl. in c. 18.5o to 22.0o range + cont. adj. of up to 1.0o
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
Measured energy flows and electric efficiency
Measurement period
hh:mm
12:40 - 14:10
Fuel gas consumption
m 3o
820.6
Measurement duration
mm:ss
89:58.67
547.2
Fuel gas flow
m3o/h
Fuel gas consumption
kW
4818.6
Electricity production (gross)
kWh
2880
Measurement duration
mm:ss
91:10.90
Electricity output (gross)
kW
1895.1
Efficiency (LHV-based)
%
39.3
14:40 - 16:10
826.3
90:35.87
547.2
4818.7
2830
89:33.16
1896.1
39.3
Measured gas engine process conditions
Measurement period
hh:mm
12:35 - 14:15
o
Combustion air temperature
C
18.5
Intake manifold pressure
bara
3.19
o
Intake manifold temperature
C
48.9
o
C
468
Exhaust gas temperature
14:35 - 16:15
18.1
3.20
49.1
467
hrs
hrs
hrs
hrs
-
24853
8564
-------
Measured gross electric power output variation (relative to actual gross electric power output)
20
15
2.5
Top-top variation
2.0
RMS variation
1.5
10
1.0
5
0.5
0
12:00
12:30
13:00
13:30
14:00
14:30
Time (hh:mm)
15:00
15:30
16:00
16:30
0.0
17:00
RMS (%)
Top-top (%)
25
-112-
74100741-GCS 12-1002
A8. CHP-unit #8 (spring 2011)
Emission data
Start
Stop
hh:mm
hh:mm
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
mbar
o
C
%
O2
1
11:45
12:15
2
12:15
12:45
Test series
3
4
12:45
13:35
13:15
14:05
Exhaust gas sampling
5
14:05
14:35
Engine-out
Catalyst-out
n/a
post
on
on
to greenhouse
to chimney
Atmospheric conditions
1020
1020
1020
1020
1020
12
12
13
13
13
49
48
45
44
43
Measured emissions
6
14:35
15:05
1020
13
42
%-v (dry)
9.06
9.06
9.06
9.01
9.00
9.00
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
6.00
585
145
203
6.00
586
147
207
6.00
586
144
205
6.10
<1
8
12
6.10
<1
8
13
6.10
<1
8
13
CH4
ppm-v (dry)
1246
1243
1242
1239
1236
1231
Cx Hy (as C3H8)
ppm-v (wet)
481
478
479
450
Combustion stoichiometry
447
444
%-v (dry)
-
8.82
1.66
8.82
8.82
8.79
1.66
1.66
1.66
Calculated emissions (dry)
8.78
1.66
8.78
1.66
CO
mg/m3o @ 3 %-v O2
1104
1106
1106
<2
<2
<2
NO as NO2
mg/m3o @ 3 %-v O2
449
455
446
23
25
25
NOx as NO2
mg/m3o @ 3 %-v O2
628
641
634
38
40
40
CH4
mg/m3o @ 3 %-v O2
1343
1340
1339
1330
1326
1320
Cx Hy as C
mg/m3o @ 3 %-v O2
1323
1314
1317
1223
1216
1205
Cx Hy as CH4
mg/m3o @ 3 %-v O2
1765
1607
CO
NO as NO2
g/GJ
g/GJ
313
127
1752
1756
1631
1621
Calculated specific emissions
314
314
<1
<1
129
126
7
7
NOx as NO2
g/GJ
178
182
180
11
11
11
CH4
g/GJ
381
380
380
377
376
375
Cx Hy as C
g/GJ
375
373
374
347
345
Cx Hy as CH4
g/GJ
501
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
1.9
9.3
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n/a
11.6
n/a
11.6
m3o/h
7470
---
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
Notes:
1)
497
498
463
460
Calculated hydrocarbon slip
1.9
1.9
1.9
1.9
9.3
9.3
8.6
8.6
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n/a
11.6
--551.9
<1
7
342
456
1.9
8.5
48
10.9
48
11.1
48
10.9
---
---
---
m 3o/h.
-113-
74100741-GCS 12-1002
A8. CHP-unit #8 (winter 2011)
Emission data
Start
Stop
hh:mm
hh:mm
1
12:40
13:10
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
2
13:10
13:40
Test series
3
4
13:40
14:40
14:10
15:10
Exhaust gas sampling
5
15:10
15:40
Engine-out
Catalyst-out
n/a
post
on
on
to chimney
to chimney
Atmospheric conditions
1020
1021
1021
1021
11
11
11
11
66
68
66
67
Measured emissions
6
15:40
16:10
mbar
o
C
%
1020
11
67
%-v (dry)
9.21
9.21
9.21
9.18
9.18
9.17
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
6.20
617
119
199
6.20
617
125
208
6.20
617
127
212
6.30
<1
8
13
6.30
<1
8
14
6.30
<1
10
17
CH4
ppm-v (dry)
1351
1350
1344
1346
1345
1334
Cx Hy (as C3H8)
ppm-v (wet)
503
494
502
503
Combustion stoichiometry
496
485
%-v (dry)
-
8.95
1.68
8.95
8.95
8.94
1.68
1.68
1.68
Calculated emissions (dry)
8.94
1.68
8.93
1.68
CO
mg/m3o @ 3 %-v O2
1179
1179
1179
<2
<2
<2
NO as NO2
mg/m3o @ 3 %-v O2
373
392
398
25
25
31
NOx as NO2
mg/m3o @ 3 %-v O2
624
652
664
42
42
53
CH4
mg/m3o @ 3 %-v O2
1475
1474
1467
1466
1465
1451
Cx Hy as C
mg/m3o @ 3 %-v O2
1402
1375
1398
1399
1379
1348
Cx Hy as CH4
mg/m3o @ 3 %-v O2
1869
1798
CO
NO as NO2
g/GJ
g/GJ
335
106
1833
1864
1865
1839
Calculated specific emissions
335
335
<1
<1
111
113
7
7
NOx as NO2
g/GJ
177
185
189
12
12
15
CH4
g/GJ
419
418
416
416
416
412
Cx Hy as C
g/GJ
398
390
397
397
392
Cx Hy as CH4
g/GJ
530
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
2.1
9.9
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n/a
11.6
n/a
11.6
m3o/h
7529
---
O2
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
Notes:
1)
520
529
529
522
Calculated hydrocarbon slip
2.1
2.1
2.1
2.1
9.7
9.9
9.9
9.7
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n/a
11.6
--547.2
1021
10
69
<1
9
383
510
2.1
9.5
50
11.7
50
11.7
49
11.7
7510
---
---
m 3o/h.
-114-
74100741-GCS 12-1002
A8. CHP-unit #8 (spring 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
11:45
12:15
9.02
9.11
9.06
0.022
6.0
6.0
6.0
0.02
580
589
585
1.9
134
168
145
5.9
189
228
203
6.7
456
499
481
8.7
1228
1264
1246
8.0
2
12:15
12:45
9.00
9.10
9.06
0.028
6.0
6.0
6.0
0.02
582
590
586
1.9
132
162
147
7.2
189
225
207
8.4
465
495
478
8.4
1227
1262
1243
8.3
Test series
3
4
12:45
13:35
13:15
14:05
8.99
8.97
9.10
9.05
9.06
9.01
0.022
0.021
6.0
6.0
6.0
6.1
6.0
6.1
0.02
0.02
581
-2
590
-1
586
-1
2.3
0.2
129
3.5
166
17.9
144
7.6
7.5
3.20
186
5.7
229
28.8
205
12.2
8.6
5.16
463
430
496
466
479
450
7.3
8.7
1225
1218
1262
1253
1242
1239
8.1
7.7
5
14:05
14:35
8.96
9.06
9.00
0.025
6.0
6.1
6.1
0.02
-2
-1
-1
0.3
3.2
29.0
8.2
4.36
5.4
46.1
13.1
6.94
367
462
447
14.9
1221
1251
1236
6.5
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
11:40 - 13:20
17.7
23.3
20.5
0.98
3.11
3.21
3.15
0.015
49.9
50.8
50.4
0.14
479
481
480
0.3
4+5+6
13:30 - 15:10
17.1
22.2
19.8
0.81
3.11
3.20
3.15
0.015
50.2
50.9
50.6
0.10
479
481
480
0.3
6
14:35
15:05
8.95
9.04
9.00
0.022
6.0
6.1
6.1
0.02
-2
0
-1
0.3
3.2
17.4
8.1
3.12
5.4
28.0
13.0
5.01
384
460
444
10.6
1220
1245
1231
5.7
-115-
74100741-GCS 12-1002
A8. CHP-unit #8 (winter 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
12:40
13:10
9.16
9.26
9.21
0.022
6.1
6.2
6.2
0.02
611
623
617
2.5
90
136
119
7.2
164
222
199
9.1
482
527
503
10.9
1330
1394
1351
12.5
2
13:10
13:40
9.15
9.28
9.21
0.026
6.1
6.2
6.2
0.02
610
623
617
2.5
87
159
125
9.3
157
250
208
11.7
465
540
494
15.7
1323
1416
1350
14.4
Test series
3
4
13:40
14:40
14:10
15:10
9.17
9.14
9.26
9.23
9.21
9.18
0.024
0.024
6.1
6.2
6.2
6.3
6.2
6.3
0.02
0.02
612
0
623
0
617
0
2.5
0.2
96
2.5
155
18.5
127
7.9
9.1
3.70
173
4.4
245
30.5
212
13.4
11.6
6.15
479
479
525
526
502
503
15.5
12.0
1305
1323
1384
1376
1344
1346
13.6
12.7
5
15:10
15:40
9.14
9.24
9.18
0.023
6.2
6.3
6.2
0.02
0
0
0
0.2
2.5
19.4
8.0
3.88
4.2
32.3
13.5
6.47
468
522
496
12.4
1326
1378
1345
11.0
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
12:35 - 14:15
17.0
20.6
18.5
0.53
3.14
3.30
3.19
0.016
48.2
50.7
48.9
0.25
467
468
468
0.2
4+5+6
14:35 - 16:15
16.7
19.8
18.1
0.58
3.15
3.24
3.20
0.015
48.8
49.5
49.1
0.13
467
468
467
0.2
6
15:40
16:10
9.12
9.23
9.17
0.023
6.2
6.3
6.3
0.02
0
0
0
0.1
2.7
24.9
10.0
4.57
4.5
40.8
16.9
7.60
458
516
485
13.0
1311
1368
1334
10.6
-116-
A8. CHP-unit #8 (spring 2011)
74100741-GCS 12-1002
-117-
A8. CHP-unit #8 (winter 2011)
74100741-GCS 12-1002
-118-
74100741-GCS 12-1002
A9. CHP-unit #9 (spring 2011)
Test location & date
Location
City
Date
***
***
05 May 2011
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remark:
hrs
hrs
hrs
***
***
***
2008
April 2009
17466
17257
17710
· Severe misfire during measurement.
Fuel gas characteristics
Type
Sample time
hh:mm
Lower heating value
kJ/m3o
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
1)
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
Measured energy flows and
Measurement period
Fuel gas consumption
Measurement duration
Fuel gas flow
Fuel gas consumption
Electricity production (gross)
Measurement duration
Electricity output (gross)
Efficiency (LHV-based)
Vee-12
Open chamber
128
142
12.0
1500
360
13.7 1)
18.0
Assumption: 96% generator efficiency
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
n/a
n/a
n/a
n/a
n/a
mm
mm
rpm
kW
bar
o
BTDC
Biogas
11:55
20380
electric efficiency
12:10 - 13:40
hh:mm
--m3o
--mm:ss
--m3o/h
--kW
560
kWh
93:18.05
mm:ss
360.1
kW
--%
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
Measured gas engine process conditions
12:05 - 13:45
Measurement period
hh:mm
o
24.2
Combustion air temperature
C
Intake manifold pressure
bara
2.25
o
Intake manifold temperature
57.2
C
o
Exhaust gas temp. LB/RB
C
503
499
n/a
n/a
n/a
n/a
n/a
hrs
hrs
hrs
hrs
-
n/a
n/a
n/a
n/a
n/a
Measured gross electric power output variation (relative to actual gross electric power output)
100
60
4.0
RMS variation
3.0
40
2.0
20
1.0
0
11:00
11:30
12:00
12:30
13:00
13:30
Time (hh:mm)
14:00
14:30
15:00
15:30
0.0
16:00
RMS (%)
Top-top (%)
80
5.0
Top-top variation
-119-
74100741-GCS 12-1002
A9. CHP-unit #9 (winter 2011)
Test location & date
Location
City
Date
Fuel gas characteristics
Type
***
***
hh:mm
Sample time
05 December 2011 Lower heating value
kJ/m3o
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remark:
hrs
hrs
hrs
***
***
***
2008
April 2009
22366
21940
22390
· Severe misfire during measurement.
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
1)
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
Measured energy flows and
Measurement period
Fuel gas consumption
Measurement duration
Fuel gas flow
Fuel gas consumption
Electricity production (gross)
Measurement duration
Electricity output (gross)
Efficiency (LHV-based)
mm
mm
rpm
kW
bar
o
BTDC
Vee-12
Open chamber
128
142
12.0
1500
360
13.7 1)
18.0
Assumption: 96% generator efficiency
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
n/a
n/a
n/a
n/a
n/a
Biogas
12:20
20370
electric efficiency
12:30 - 14:00
hh:mm
--m3o
--mm:ss
--m3o/h
kW
--kWh
524.8
mm:ss
88:14.82
kW
----%
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
Measured gas engine process conditions
12:25 - 13:55
Measurement period
hh:mm
o
Combustion air temperature
C
8.4
Intake manifold pressure
bara
2.28
o
Intake manifold temperature
C
60.2
o
Exhaust gas temp. LB/RB
C
499
494
n/a
n/a
n/a
n/a
n/a
hrs
hrs
hrs
hrs
-
n/a
n/a
n/a
n/a
n/a
Measured gross electric power output variation (relative to actual gross electric power output)
5.0
80
Top-top variation
4.0
60
RMS variation
3.0
40
2.0
20
1.0
0
12:00
12:30
13:00
13:30
14:00
14:30
Time (hh:mm)
15:00
15:30
16:00
16:30
0.0
17:00
RMS (%)
Top-top (%)
100
-120-
74100741-GCS 12-1002
A9. CHP-unit #9 (spring 2011)
Emission data
Start
Stop
hh:mm
hh:mm
1
12:10
12:40
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
mbar
o
C
%
O2
1023
17
32
2
12:40
13:10
Test series
3
4
13:10
n/a
13:40
n/a
Exhaust gas sampling
Engine-out
n/a
n/a
to chimney
Atmospheric conditions
1023
1022
n/a
17
18
n/a
31
30
n/a
Measured emissions
5
n/a
n/a
6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
%-v (dry)
6.49
6.50
6.51
n/a
n/a
n/a
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
12.50
303
200
257
12.50
299
206
257
12.40
298
205
258
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
CH4
ppm-v (dry)
362
350
350
n/a
n/a
n/a
Cx Hy (as C3H8)
ppm-v (wet)
130
128
127
n/a
Combustion stoichiometry
n/a
n/a
%-v (dry)
-
6.41
1.43
6.42
6.43
n/a
1.43
1.43
n/a
Calculated emissions (dry)
n/a
n/a
n/a
n/a
CO
mg/m3o @ 3 %-v O2
470
464
463
n/a
n/a
n/a
NO as NO2
mg/m3o @ 3 %-v O2
509
525
522
n/a
n/a
n/a
NOx as NO2
mg/m3o @ 3 %-v O2
654
654
657
n/a
n/a
n/a
CH4
mg/m3o @ 3 %-v O2
321
310
311
n/a
n/a
n/a
Cx Hy as C
mg/m3o
mg/m3o
@ 3 %-v O2
299
294
292
n/a
n/a
n/a
@ 3 %-v O2
398
n/a
n/a
CO
NO as NO2
g/GJ
g/GJ
142
154
392
390
Calculated specific
140
140
159
158
n/a
n/a
n/a
n/a
NOx as NO2
g/GJ
198
198
199
n/a
n/a
n/a
CH4
g/GJ
97
94
94
n/a
n/a
n/a
Cx Hy as C
g/GJ
90
89
88
n/a
n/a
Cx Hy as CH4
g/GJ
120
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
0.5
2.2
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n/a
13.0
n/a
13.0
m3o/h
n/a
n/a
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
Cx Hy as CH4
Notes:
1)
n/a
emissions
n/a
n/a
119
118
n/a
n/a
Calculated hydrocarbon slip
0.5
0.5
n/a
n/a
2.2
2.2
n/a
n/a
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n/a
13.0
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
m 3o/h.
-121-
74100741-GCS 12-1002
A9. CHP-unit #9 (winter 2011)
Emission data
Start
Stop
hh:mm
hh:mm
1
12:30
13:00
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
mbar
o
C
%
O2
999
6
78
2
13:00
13:30
Test series
3
4
13:30
n/a
14:00
n/a
Exhaust gas sampling
Engine-out
n/a
n/a
to chimney
Atmospheric conditions
1000
1000
n/a
5
4
n/a
76
79
n/a
Measured emissions
5
n/a
n/a
6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
%-v (dry)
6.77
6.76
6.75
n/a
n/a
n/a
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
11.80
331
213
268
11.80
331
214
272
11.90
331
214
272
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
CH4
ppm-v (dry)
364
368
367
n/a
n/a
n/a
Cx Hy (as C3H8)
ppm-v (wet)
123
124
127
n/a
Combustion stoichiometry
n/a
n/a
%-v (dry)
-
6.69
1.46
6.68
6.67
n/a
1.46
1.45
n/a
Calculated emissions (dry)
n/a
n/a
n/a
n/a
CO
mg/m3o @ 3 %-v O2
524
523
523
n/a
n/a
n/a
NO as NO2
mg/m3o @ 3 %-v O2
553
555
555
n/a
n/a
n/a
NOx as NO2
mg/m3o @ 3 %-v O2
695
705
705
n/a
n/a
n/a
CH4
mg/m3o @ 3 %-v O2
329
332
331
n/a
n/a
n/a
Cx Hy as C
mg/m3o
mg/m3o
@ 3 %-v O2
287
290
297
n/a
n/a
n/a
@ 3 %-v O2
383
n/a
n/a
CO
NO as NO2
g/GJ
g/GJ
157
166
387
396
Calculated specific
157
157
166
166
n/a
n/a
n/a
n/a
NOx as NO2
g/GJ
208
211
n/a
n/a
CH4
g/GJ
99
100
99
n/a
n/a
n/a
Cx Hy as C
g/GJ
86
87
89
n/a
n/a
n/a
Cx Hy as CH4
g/GJ
115
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
0.5
2.1
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n/a
13.0
n/a
13.0
m3o/h
n/a
n/a
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
Cx Hy as CH4
Notes:
1)
211
n/a
emissions
n/a
n/a
n/a
116
119
n/a
n/a
Calculated hydrocarbon slip
0.5
0.5
n/a
n/a
2.2
2.2
n/a
n/a
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n/a
13.0
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
m 3o/h.
-122-
74100741-GCS 12-1002
A9. CHP-unit #9 (spring 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
12:10
12:40
6.38
6.57
6.49
0.040
12.5
12.6
12.5
0.03
298
308
303
2.1
175
224
200
8.0
230
271
257
8.3
102
179
130
16.3
296
485
362
43.7
2
12:40
13:10
6.35
6.58
6.50
0.041
12.4
12.6
12.5
0.04
294
304
299
2.0
186
228
206
8.2
237
281
257
8.6
101
183
128
16.2
290
473
350
40.6
Test series
3
4
13:10
n/a
13:40
n/a
6.38
n/a
6.66
n/a
6.51
n/a
0.048
n/a
12.3
n/a
12.5
n/a
12.4
n/a
0.03
n/a
293
n/a
305
n/a
298
n/a
2.4
n/a
180
n/a
233
n/a
205
n/a
9.8
n/a
231
n/a
287
n/a
258
n/a
10.2
n/a
100
n/a
202
n/a
127
n/a
16.4
n/a
287
n/a
503
n/a
350
n/a
42.1
n/a
5
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature LB/RB
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
12:05 - 13:45
17.9
29.3
24.2
2.78
2.18
2.34
2.25
0.023
56.4
58.2
57.2
0.26
499
/
496
505
/
501
503
/
499
0.9
/
0.8
n/a
n/a
n/a
n/a
4+5+6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
/
n/a
/
n/a
/
n/a
/
n/a
6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
-123-
74100741-GCS 12-1002
A9. CHP-unit #9 (winter 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
12:30
13:00
6.70
6.82
6.77
0.025
11.7
11.9
11.8
0.03
327
335
331
1.9
195
235
213
7.0
246
294
268
8.2
96
167
123
12.8
316
492
364
37.6
2
13:00
13:30
6.67
6.85
6.76
0.034
11.7
11.9
11.8
0.05
326
335
331
2.0
193
233
214
8.9
249
294
272
9.8
96
157
124
14.7
314
487
368
39.9
Test series
3
4
13:30
n/a
13:55
n/a
6.69
n/a
6.83
n/a
6.75
n/a
0.030
n/a
11.8
n/a
11.9
n/a
11.9
n/a
0.04
n/a
327
n/a
334
n/a
331
n/a
1.8
n/a
186
n/a
235
n/a
214
n/a
8.5
n/a
242
n/a
296
n/a
272
n/a
9.9
n/a
94
n/a
159
n/a
127
n/a
13.9
n/a
315
n/a
477
n/a
367
n/a
37.8
n/a
5
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
Gas engine process condition data statistics
Test series
Parameter
Combustion air temperature
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature LB/RB
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
12:25 - 13:55
5.6
13.0
8.4
1.26
2.23
2.33
2.28
0.015
59.1
60.9
60.2
0.21
497
/
492
501
/
496
499
/
494
0.5
/
0.5
n/a
n/a
n/a
n/a
4+5+6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
/
n/a
/
n/a
/
n/a
/
n/a
6
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
n/a
-124-
A9. CHP-unit #9 (spring 2011)
74100741-GCS 12-1002
-125-
A9. CHP-unit #9 (winter 2011)
74100741-GCS 12-1002
-126-
74100741-GCS 12-1002
A10. CHP-unit #10 (spring 2011)
Test location & date
Location
City
Date
***
***
24 May 2011
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks:
hrs
hrs
hrs
***
***
***
2006
July 2006
23772
22429
24429
· 22586 running hours: turbochargers and cylinder heads #4 & #7 w ere
replaced.
· Engine is equipped w ith steel pistons (low top-land crevice volume?).
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
Measured energy flows and
Measurement period
Fuel gas consumption
Measurement duration
Fuel gas flow
Fuel gas consumption
Electricity production (gross)
Measurement duration
Electricity output (gross)
Efficiency (LHV-based)
***
***
--2006
August 2006
Fuel gas characteristics
Type
hh:mm
Sample time
kJ/m3o
Lower heating value
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
Natural gas
11:40
32170
Vee-20
Prechamber
mm
190
mm
220
12.0
rpm
1500
kW
3041
bar
20.3 1)
o
BTDC 23.0 (20.0+3.0 offset)
1)
Assumption: 96% generator efficiency
2)
Continuous adjustment per cylinder up to 1.0o retard
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
electric efficiency
11:45 - 13:15
hh:mm
1223.2
m3o
92:04.18
mm:ss
797.1
m3o/h
7123.1
kW
4624
kWh
91:48.88
mm:ss
kW
3021.7
%
42.4
Measured gas engine process conditions
11:40 - 13:20
Measurement period
hh:mm
o
Combustion air temp. LB/RB
C
18.1
19.2
Intake manifold pressure
bara
3.83
o
Intake manifold temperature
44.3
C
o
409
Exhaust gas temperature
C
hrs
hrs
hrs
hrs
-
2)
c. 23700
---------
13:40 - 15:10
1192.9
89:47.89
797.1
7122.8
4500
89:21.99
3021.3
42.4
13:35 - 15:15
19.1
19.7
3.83
44.3
409
Measured gross electric power output variation (relative to actual gross electric power output)
2.5
25
15
2.0
RMS variation
1.5
10
1.0
5
0.5
0
11:00
11:30
12:00
12:30
13:00
13:30
Time (hh:mm)
14:00
14:30
15:00
15:30
0.0
16:00
RMS (%)
Top-top (%)
20
Top-top variation
-127-
74100741-GCS 12-1002
A10. CHP-unit #10 (winter 2011)
Test location & date
Location
City
Date
Fuel gas characteristics
Type
***
***
hh:mm
Sample time
14 November 2011 Lower heating value
kJ/m3o
Gas engine characteristics
Make
Type
Serial number
Build year
Commissioning date
Running hours
Last maintenance
Next maintenance
Maintenance remarks:
hrs
hrs
hrs
***
***
***
2006
July 2006
25969
25891
27891
· Engine is equipped w ith steel pistons (low top-land crevice volume?).
Catalyst characteristics
Make
Type
Serial number
Build year
Commissioning date
-
Measured energy flows and
Measurement period
Fuel gas consumption
Measurement duration
Fuel gas flow
Fuel gas consumption
Electricity production (gross)
Measurement duration
Electricity output (gross)
Efficiency (LHV-based)
Cylinder configuration
Combustion system
Bore
Stroke
Compression ratio
Engine speed
Rated el. power output
BMEP
Ignition timing
Notes:
Vee-20
Prechamber
mm
190
mm
220
12.0
rpm
1500
kW
3041
bar
20.3 1)
o
BTDC 23.0 (20.0+3.0 offset)
1)
Assumption: 96% generator efficiency
2)
Continuous adjustment per cylinder up to 2.0o retard
Running hours
Running hours injection
Last maintenance
Next maintenance
Maintenance remarks
***
***
--2006
August 2006
Natural gas
13:05
31760
electric efficiency
13:15 - 14:45
hh:mm
1207.0
m3o
89:10.19
mm:ss
812.2
m3o/h
7165.0
kW
4496
kWh
89:20.97
mm:ss
kW
3019.2
%
42.1
hrs
hrs
hrs
hrs
-
2)
c. 25900
----every 4000 running hours
06-2010: extra oxicat-row
16:15 - 17:45
1190.0
88:16.86
808.8
7135.2
4474
88:54.96
3019.0
42.3
Measured gas engine process conditions
13:10 - 14:50
Measurement period
hh:mm
o
Combustion air temp. LB/RB
C
12.8
18.3
Intake manifold pressure
bara
3.89
o
Intake manifold temperature
44.6
C
o
406
Exhaust gas temperature
C
16:10 - 17:50
13.6
18.8
3.89
44.6
406
Measured gross electric power output variation (relative to actual gross electric power output)
20
15
2.5
Top-top variation
2.0
RMS variation
1.5
10
1.0
5
0.5
0
13:00
13:30
14:00
14:30
15:00
15:30
Time (hh:mm)
16:00
16:30
17:00
17:30
0.0
18:00
RMS (%)
Top-top (%)
25
-128-
74100741-GCS 12-1002
A10. CHP-unit #10 (spring 2011)
Emission data
Start
Stop
hh:mm
hh:mm
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
mbar
o
C
%
O2
1
11:45
12:15
2
12:15
12:45
Test series
3
4
12:45
13:40
13:15
14:10
Exhaust gas sampling
5
14:10
14:40
Engine-out
Catalyst-out
n/a
post
on
on
to greenhouse
to chimney
Atmospheric conditions
1025
1025
1025
1026
1026
15
15
15
16
16
48
49
48
48
49
Measured emissions
6
14:40
15:10
1026
16
47
%-v (dry)
10.57
10.56
10.56
10.53
10.53
10.52
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
5.90
306
117
185
5.90
305
117
185
5.90
304
117
187
5.90
<1
9
17
5.90
<1
8
16
6.00
<1
8
14
CH4
ppm-v (dry)
1048
1044
1041
1034
1034
1040
Cx Hy (as C3H8)
ppm-v (wet)
387
384
381
363
Combustion stoichiometry
360
362
%-v (dry)
-
10.38
1.90
10.37
10.37
10.35
1.89
1.90
1.89
Calculated emissions (dry)
10.35
1.89
10.34
1.89
CO
mg/m3o @ 3 %-v O2
661
659
656
<2
<2
<2
NO as NO2
mg/m3o @ 3 %-v O2
415
414
414
32
30
27
NOx as NO2
mg/m3o @ 3 %-v O2
656
655
662
60
55
50
CH4
mg/m3o @ 3 %-v O2
1294
1288
1284
1272
1272
1278
Cx Hy as C
mg/m3o @ 3 %-v O2
1204
1193
1184
1110
1101
1106
Cx Hy as CH4
mg/m3o @ 3 %-v O2
1605
1475
CO
NO as NO2
g/GJ
g/GJ
187
118
1591
1579
1480
1468
Calculated specific emissions
187
186
<1
<1
117
117
9
8
NOx as NO2
g/GJ
186
186
188
17
16
14
CH4
g/GJ
367
365
364
360
360
362
Cx Hy as C
g/GJ
341
338
336
315
312
Cx Hy as CH4
g/GJ
455
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
1.8
8.5
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n/a
10.5
n/a
10.5
m3o/h
12540
---
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
Notes:
1)
451
447
419
416
Calculated hydrocarbon slip
1.8
1.8
1.8
1.8
8.4
8.4
7.8
7.8
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n/a
10.5
--797.1
<1
8
313
418
1.8
7.8
45
9.3
45
9.3
45
9.3
---
---
---
m 3o/h.
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74100741-GCS 12-1002
A10. CHP-unit #10 (winter 2011)
Emission data
Start
Stop
hh:mm
hh:mm
1
13:15
13:45
Sample location
→ pre- or post exhaust gas condensor
Urea injection
Exhaust gas routing
Pressure
Temperature
Relative humidity
2
13:45
14:15
Test series
3
4
14:15
16:15
14:45
16:45
Exhaust gas sampling
5
16:45
17:15
Engine-out
Catalyst-out
n/a
post
on
on
to chimney
to chimney
Atmospheric conditions
1021
1021
1021
1021
6
6
7
7
89
89
91
91
Measured emissions
6
17:15
17:45
mbar
o
C
%
1021
6
88
%-v (dry)
10.63
10.64
10.65
10.60
10.60
10.60
%-v (dry)
ppm-v (dry)
ppm-v (dry)
ppm-v (dry)
5.40
334
90
168
5.50
332
89
168
5.50
332
87
166
5.50
<1
10
19
5.50
<1
9
18
5.50
<1
9
17
CH4
ppm-v (dry)
1102
1104
1104
1084
1080
1080
Cx Hy (as C3H8)
ppm-v (wet)
409
411
411
364
Combustion stoichiometry
360
360
%-v (dry)
-
10.43
1.91
10.44
10.45
10.41
1.91
1.91
1.90
Calculated emissions (dry)
10.41
1.90
10.41
1.90
CO
mg/m3o @ 3 %-v O2
726
723
723
<2
<2
<2
NO as NO2
mg/m3o @ 3 %-v O2
321
318
311
34
33
32
NOx as NO2
mg/m3o @ 3 %-v O2
599
600
593
66
63
61
CH4
mg/m3o @ 3 %-v O2
1369
1372
1374
1342
1337
1337
Cx Hy as C
mg/m3o @ 3 %-v O2
1278
1285
1286
1136
1122
1124
Cx Hy as CH4
mg/m3o @ 3 %-v O2
1704
1499
CO
NO as NO2
g/GJ
g/GJ
206
91
1713
1715
1514
1496
Calculated specific emissions
205
205
<1
<1
90
88
10
9
NOx as NO2
g/GJ
170
170
168
19
18
17
CH4
g/GJ
388
389
390
381
379
379
Cx Hy as C
g/GJ
363
364
365
322
318
Cx Hy as CH4
g/GJ
484
Methane slip
Hydrocarbon slip (CO2-eq.)
%
kg CO2-eq./GJ
1.9
9.0
Exhaust gas sample temp.
H2O
Exhaust gas flow 1)
o
C
%-v (wet)
n/a
10.4
n/a
10.4
m3o/h
12741
---
O2
CO2
CO
NO
NOx
O2 (complete combustion)
Air-to-fuel ratio (λ)
Notes:
1)
486
486
430
424
Calculated hydrocarbon slip
1.9
1.9
1.9
1.9
9.1
9.1
8.0
7.9
Measured/calculated exhaust gas conditions
Based on average fuel gas consumption of:
n/a
10.4
--810.5
1021
6
92
<1
9
319
425
1.9
7.9
54
10.5
53
10.5
50
10.5
12639
---
---
m 3o/h.
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74100741-GCS 12-1002
A10. CHP-unit #10 (spring 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
11:45
12:15
10.53
10.61
10.57
0.023
5.9
5.9
5.9
0.02
304
309
306
1.2
112
121
117
1.9
179
191
185
2.3
370
401
387
7.7
1038
1064
1048
5.0
2
12:15
12:45
10.52
10.59
10.56
0.025
5.9
5.9
5.9
0.02
303
307
305
1.1
111
121
117
1.9
179
190
185
2.2
365
399
384
8.3
1035
1055
1044
4.5
Test series
3
4
12:45
13:40
13:15
14:10
10.52
10.49
10.59
10.56
10.56
10.53
0.024
0.023
5.9
5.9
5.9
6.0
5.9
5.9
0.02
0.02
302
-1
307
0
304
0
1.2
0.2
114
6.2
122
13.6
117
9.2
1.9
1.87
183
11.8
192
24.8
187
17.0
2.2
3.41
364
348
396
375
381
363
8.1
7.9
1032
1025
1048
1050
1041
1034
3.8
4.1
5
14:10
14:40
10.49
10.56
10.53
0.023
5.9
6.0
5.9
0.02
-1
0
0
0.3
5.6
11.8
8.4
1.69
10.5
21.7
15.6
3.13
347
375
360
8.2
1025
1044
1034
3.8
6
14:40
15:10
10.46
10.56
10.52
0.024
5.9
6.0
6.0
0.02
-1
0
-1
0.3
4.7
12.7
7.6
1.73
8.7
24.3
14.1
3.18
339
378
362
8.9
1023
1050
1040
5.2
Gas engine process condition data statistics
Test series
Parameter
Combustion air temp. LB/RB
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
11:40 - 13:20
16.7
/
16.9
20.4
/
22.7
18.1
/
19.2
0.53
/
0.90
3.80
3.86
3.83
0.014
43.8
44.8
44.3
0.14
408
409
409
0.3
4+5+6
13:35 - 15:15
18.1
/
17.9
21.0
/
22.5
19.1
/
19.7
0.48
/
0.74
3.80
3.86
3.83
0.014
43.4
45.2
44.3
0.16
409
410
409
0.2
-131-
74100741-GCS 12-1002
A10. CHP-unit #10 (winter 2011)
Emission data statistics
Parameter
O2
Start
Stop
%-v
(dry)
CO2
%-v
(dry)
CO
ppm-v
(dry)
NO
ppm-v
(dry)
NOx
ppm-v
(dry)
Cx Hy (as C3H8)
ppm-v
(wet)
CH4
ppm-v
(dry)
hh:mm
hh:mm
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
min
max
avg
st.dev.
1
13:15
13:45
10.59
10.68
10.63
0.023
5.4
5.5
5.4
0.02
330
337
334
1.7
86
95
90
1.9
162
175
168
2.5
379
427
409
11.7
1093
1113
1102
4.6
2
13:45
14:15
10.60
10.67
10.64
0.023
5.4
5.5
5.4
0.02
329
334
332
1.2
85
93
89
1.8
164
172
168
2.2
371
435
411
14.8
1096
1114
1104
4.1
Test series
3
4
14:15
16:15
14:45
16:45
10.60
10.54
10.71
10.64
10.65
10.60
0.029
0.025
5.4
5.5
5.5
5.5
5.4
5.5
0.02
0.02
329
0
334
1
332
1
1.2
0.2
85
5.3
92
15.5
87
9.6
1.7
2.77
163
10.5
172
29.3
166
18.5
2.6
5.05
393
344
428
383
411
364
9.8
10.1
1096
1077
1112
1092
1104
1084
3.8
4.1
5
16:45
17:15
10.56
10.63
10.60
0.024
5.5
5.5
5.5
0.02
-1
1
0
0.5
5.1
14.1
9.2
2.50
10.3
26.7
17.7
4.55
337
381
360
10.8
1071
1090
1080
4.1
6
17:15
17:45
10.56
10.63
10.60
0.023
5.4
5.5
5.5
0.02
-2
0
-1
0.3
4.5
13.8
8.9
2.69
9.1
26.0
17.2
4.95
339
381
360
9.7
1070
1089
1080
4.5
Gas engine process condition data statistics
Test series
Parameter
Combustion air temp. LB/RB
Intake manifold pressure
Intake manifold temperature
Exhaust gas temperature
Period hh:mm
o
C
min
max
avg
st.dev.
bara min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
o
C
min
max
avg
st.dev.
1 + 2+ 3
13:10 - 14:50
11.5
/
15.5
17.7
/
22.4
12.8
/
18.3
0.71
/
0.75
3.86
3.92
3.89
0.014
44.2
44.9
44.6
0.17
406
407
406
0.1
4+5+6
16:10 - 17:50
11.9
/
16.1
16.5
/
20.2
13.6
/
18.8
0.83
/
0.84
3.86
3.92
3.89
0.014
44.2
45.1
44.6
0.17
406
406
406
0.1
-132-
A10. CHP-unit #10 (spring 2011)
74100741-GCS 12-1002
-133-
A10. CHP-unit #10 (winter 2011)
74100741-GCS 12-1002
-134-
74100741-GCS 12-1002
ANNEX B – SGS EMISSION MEASUREMENT AND CALCULATION
METHODS
The emission measurements and calculations were performed by SGS Environmental
Services BV under supervision of KEMA. This annex gives an overview of the measurement
and calculation methods used by SGS Environmental Services BV and provides information
about the realized measurement uncertainties.
In general, it is important to know the uncertainty in the reported emission measurement
results. After all, when reviewing measurement results against agreed values, e.g. against
values guaranteed by suppliers or against emission limit values imposed by governments,
the measurement uncertainty may be attributed to one of the parties.
The measurement uncertainty is defined as twice the standard deviation. This means that
with a certainty of 95%, the actual value lies within the specified uncertainty range.
For emission measurements in exhaust gas, the uncertainty of the measurement results is
determined by:
−
uncertainties that originate from sampling error sources (more or less representative
sampling), and
−
errors that are related to the measurement method, e.g. the exhaust gas treatment, the
accuracy of calibration gases and the specifications of the analysis equipment used such
as the measurement range, drift, sensitivity for interfering components and linearity.
In the following sections these points are discussed in more detail.
EMISSION MEASUREMENT UNCERTAINTY ORIGINATING FROM SAMPLING
The gaseous sampling is carried out in accordance with EN 15259. The extent to which the
composition of the exhaust gas sample that it is analyzed is representative for the
composition of the entire exhaust gas flow depends on a number of factors, where the
method of sampling in relation to whether or not the exhaust gases are (in)homogeneous at
that point is particularly important.
The relation between the (in) homogeneity of the exhaust gases, the sampling technique and
the resulting measurement uncertainty for gaseous exhaust gas components is specified in
more detail below, using the relative difference between the highest and lowest concentration
ΔC.
-135-
74100741-GCS 12-1002
ΔC in equation
ΔC =
C max − C min
× 100%
0,5 × (Cmax + C min )
where:
ΔC
= relative difference between the highest and lowest concentration,
Cmax
Cmin
= highest concentration in the exhaust gas stream,
= lowest concentration in the exhaust gas stream.
Table B1 Measurement uncertainty as a function of ΔC and the sampling technique
(applicable for gaseous exhaust gas components only).
ΔC
uncertainty of the measured concentration (% of the measurement
value)
point sampling
5%
10 %
30 %
50 %
100 %
200 %
line sampling
grid sampling
±
2.5 %
± 5 %
± 15 %
±
±
±
1 %
2 %
6 %
± 0.5 %
± 1.5 %
± 3 %
± 25
± 50
± 100
± 11 %
± 22 %
± 45 %
± 6.5 %
± 13 %
± 26 %
%
%
%
The results in this report are obtained using point sampling of the exhaust gasses. Based on
grid measurements at gas engines, the following typical ΔC values for different exhaust gas
components have been determined:
- ≤1% for O2 and CO,
3% for CxHy,
6% for NOx without urea injection, and
-
10% for NOx with urea injection.
For point sampling, these ΔC values result in a maximum measurement uncertainty of:
-
≤ 2% for O2, CO, and CxHy,
3% for NOx without urea injection, and
5% for NOx with urea injection.
-136-
74100741-GCS 12-1002
SPECIFICATION OF THE EMISSION ANALYSIS METHODS
The emission analysis methods are briefly explained below. This explanation is based on the
following assumptions and definitions:
−
if on-line measurement equipment (analyzers) is used, these analyzers are calibrated
with “work standards” on location prior to the measurements. Work standards are gas
mixtures in gas cylinders with an accurately known composition. The work standards that
SGS uses are related to primary reference material (PRM) from the Dutch Institute of
Measurements with an uncertainty of ≤ 1%. The work standards used have an
uncertainty of 1.5%; this has been shown in the presence of the RvA and the certification
data can be obtained on request. PRM and work standards are derivable to international
standards via the Dutch Institute of Measurements;
−
the detection limit is defined as three times the standard deviation; the analysis
uncertainty is defined as twice the standard deviation.
O2 concentration in dry exhaust gas (instrumental analysis – Servomex 4900)
− sampling
EN 15259
− measurement principle
on-line, continuously recording, paramagnetic
− standard regulation
in accordance with EN 14789
− measurement range
0 - 25 %-v
− detection limit
0.3 %-v
− monitor used
KPS 3584
− perf. characteristics
the performance characteristics are available on request
− calibration gases
N2 (zero gas), 9.01 %-v and air
− analysis uncertainty
measured values
measured values
5 - 10 %-v: ± 0.13 %-v
10 - 20 %-v: ± 0.21 %-v
CO2 concentration in dry exhaust gas (instrumental analysis – Servomex 4900)
− sampling
EN-15259
− measurement principle
on-line, continuously recording, NDIR
− standard regulation
in accordance with EN 12039
− measurement range
0 - 20 %-v
− detection limit
0.1 %-v
− monitor used
KPS 3584
− perf. characteristics
the performance characteristics are available on request
− calibration gases
N2 (zero gas), 4.01 %-v and 17.93 %-v
− analysis uncertainty
measured values 0 - 4 %-v: ± 0.1 %-v
-137-
74100741-GCS 12-1002
CO concentration in dry exhaust gas (instrumental analysis – Servomex 4900)
− sampling
EN-15259
− measurement principle
on-line, continuously recording, NDIR
− standard regulation
in accordance with EN 15058
− measurement range
0 - 3000 ppm-v
− detection limit
1.1 ppm-v
− monitor used
KPS 3584
− perf. characteristics
the performance characteristics are available on request
− calibration gases
N2 (zero gas), 40.3 ppm-v, 188 ppm-v and 1916 ppm-v
− uncertainty of analysis
measured values
0-
50 ppm-v: ± 0.7 ppm-v
measured values 50 - 200 ppm-v: ± 3
measured values 200 - 2000 ppm-v: ± 34
ppm-v
ppm-v
CxHy concentration (total hydrocarbons, instrumental analysis – Ratfisch RS-200)
− sampling
EN-15259
− measurement principle
on-line, continuously recording, FID (wet base)
− standard regulation
in accordance with EN 13526
− measurement range
0 – 1000 ppm-v
− detection limit
0.26 ppm-v
− monitor used
EAAR-08-30
− perf. characteristics
the performance characteristics are available on request
− calibration gases
N2 (zero gas), 88.9 ppm-v and 889 ppm-v
− uncertainty of analysis
measured values
10 - 100 ppm-v: ± 2 ppm-v C3H8
measured values 100 - 1000 ppm-v: ± 14 ppm-v C3H8
NO and NOx-concentration in dry exhaust gas (instrumental analysis - Ecophysics)
− sampling
EN 15259
− measurement principle
on-line, continuously recording, chemoluminescence
− standard regulation
in accordance with EN 14792
− measurement range
0-100 ppm-v; 0-1000 ppm-v
− detection limit
2.4 ppm-v
− monitor used
KPS 1207
− perf. characteristics
the performance characteristics are available on request
− calibration gases
N2 (zero gas), 10.6 ppm-v, 90,9 ppm-v and 227.9 ppm-v
− analysis uncertainty
measured values 0 - 10 ppm-v: ± 0.6 ppm-v
measured values 10 - 100 ppm-v: ± 1.6 ppm-v
measured values 100 - 250 ppm-v: ± 3.9 ppm-v
-138-
74100741-GCS 12-1002
CH4 concentration in dry exhaust gas (instrumental analysis – Maihak Unor 610)
− sampling
EN 15259
− measurement principle
on-line, continuously recording, IR
− standard regulation
KEMA method (analyzer is owned by KEMA)
− measurement range
0-5000 ppm-v
− detection limit
10 ppm-v
− monitor used
G0043
− perf. characteristics
the performance characteristics are available on request
− calibration gases
N2 (zero gas), 4501 ppm-v
− analysis uncertainty
measured values
250 - 1000 ppm-v: ± 20 ppm-v
measured values
1000 - 5000 ppm-v: ± 30 ppm-v
EMISSION CALCULATIONS
The following emission calculations were used.
Conversion from wet exhaust gas to dry exhaust gas
C dry = C wet .
100
(100 - H2 O )
in which:
Cdry
= volume concentration of emission component in dry exhaust gas [ppm-v],
Cwet
= volume concentration of emission component in wet exhaust gas [ppm-v],
H2O = water vapour volume concentration in (wet) exhaust gas [%-v].
Conversion from actual oxygen concentration to reference oxygen concentration
CB = C A ⋅
20.95 − B
20.95 − A
or
C B' = C A ⋅
20.95 − B
⋅ρ
20.95 − A
in which:
CB
= volume concentration of emission component in dry exhaust gas at reference
oxygen concentration [ppm-v],
CB'
= mass concentration of emission component in dry exhaust gas at reference oxygen
concentration [mg/m3o],
CA
= volume concentration of emission component in dry exhaust gas at actual oxygen
concentration [ppm-v],
B
= reference oxygen concentration [%-v],
A
= actual (measured) oxygen concentration in dry exhaust gas [%-v],
ρ
= specific mass of emission component [kg/m3o].
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74100741-GCS 12-1002
The specific mass ρ of emission components used is:
CO
org.comp., as C
H2O
CH4
- 1.25 kg/m3o
- 1.61 kg/m3o
- 0.80 kg/m3o
- 0.714 kg/m3o
CO2
org.comp. as C3H8
NOx as NO2
- 1.96 kg/m3o
- 1.96 kg/m3o
- 2.05 kg/m3o
Calculation of CxHy emission in mg C/m3o at 3%-v O2
C X H Y (as C ) = C C 3 H 8 ⋅
in which:
CxHy (as C)
CC3H8
3
A
n
M
22.41
20.95 − 3 n ⋅ M
⋅
20.95 − A 22.41
= mass concentration of CxHy emission, expressed as C (carbon), in dry
exhaust gas at 3%-v reference oxygen concentration [mg C/m3o at 3%-v O2],
= volume concentration of CxHy emission, measured as C3H8, in dry exhaust
gas at actual oxygen concentration [ppm-v],
= reference oxygen concentration [%-v],
= actual (measured) oxygen concentration in dry exhaust gas [%-v],
= number of carbon atoms per C3H8 molecule (= 3),
= molar mass of C (carbon); (= 12.011 kg/kmol),
= molar volume of ideal gas [m3o/kmol].
Calculation of specific emissions in g/GJ
E[ g / GJ ] = C X ⋅
R
20.95
⋅ρ⋅ 0
20.95 − X
Hi
in which:
E[g/GJ] = specific emission of component [g/GJ],
CX
= volume concentration of emission component in dry exhaust gas at actual oxygen
concentration [ppm-v],
X
= actual (measured) oxygen concentration in dry exhaust gas [%-v],
ρ
= specific mass of emission component [kg/m3o],
R0
= volume of dry exhaust gas formed per volume of fuel gas for stoichiometric
combustion [m3o/m3o],
= lower heating value of fuel gas [MJ/m3o].
Hi
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74100741-GCS 12-1002
Calculation of air-to-fuel ratio (λ)
λ = 1+
R0 ⋅ X '
L0 ⋅ (20.95 − X ' )
in which:
λ
= air-to-fuel ratio [-],
R0
= volume of dry exhaust gas formed per volume of fuel gas for stoichiometric
L0
X'
combustion [m3o/m3o],
= volume of dry combustion air per volume of fuel gas required for stoichiometric
combustion [m3o/m3o],
= actual (measured) oxygen concentration in dry exhaust gas, corrected for
incomplete combustion products [%-v].
Calculation of methane slip
ECH 4 =
ECH 4 [ g / GJ ] ⋅ H i
CH 4
10000
in which:
= methane slip [% of fuel gas energy input],
ECH4
ECH4 [g/GJ] = specific emission of CH4 [g/GJ],
Hi CH4
= lower heating value of CH4 [MJ/kg]; (= 50).
Calculation of hydrocarbon slip (CO2-eq.)
30
EGWPnett = EC x H y [ g / GJ ] ⋅ 0.0249
in which:
EGWP_nett = hydrocarbon slip [kg CO2-eq./GJ],
ECxHy [g/GJ] = specific emission of CxHy [g C/GJ].
TOTAL EMISSION MEASUREMENT UNCERTAINTY
Table B2 shows the total emission measurement uncertainties for the different exhaust gas
components at given concentration levels.
30
Based on memorandum Koolwaterstofemissies en GWP-effect by Infomil (dated September 4th,
2007).
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74100741-GCS 12-1002
Table B2 Total emission measurement uncertainty.
Measurement uncertainty
(± % of measured values, 2s)
Component
sampling
analysis
total
O2
all measured concentrations
2
2
3
CO2
all measured concentrations
2
3
4
2
14
2
6
14
3
6
5*
5*
3 **
9
6
5
10
8
6
2
2
5
3
6
4
2
2
10
5
11
6
CO
10
500
1000
NOx
20
50
100-1000
CH4
300
1000-2000
CxHy
300
1000-2000
mg/m3o at 3% O2
mg/m3o at 3% O2
mg/m3o at 3% O2
mg/m3o at 3% O2
mg/m3o at 3% O2
mg/m3o at 3% O2
mg/m3o at 3% O2
mg/m3o at 3% O2
mg/m3o at 3% O2
mg/m3o at 3% O2
* with urea injection
** without urea injection
ACCREDITATION AND RESPONSIBILITY
RvA Testing accreditation L-092
measurements:
−
31
is applicable and includes the following emission
on-line determination of gaseous O2, CO2, CO, NO, NOx and CxHy.
The CH4 emission measurement is not included in this accreditation.
31
Accreditation is held by SGS Environmental Services BV.