Selection of best FGD technology for Africa
Rüdiger Baege
Hamon Enviroserv GmbH Essen / Germany
Andrew Twyford
Hamon South-Africa / Johannesburg
19-21 July 2016, Johannesburg
1 CONTENT
1
2
3
4
5
6
7
CONTENT.......................................................................................................................2
ABSTRACT ....................................................................................................................3
INTRODUCTION ...........................................................................................................4
3.1 Worldwide status of air quality ..................................................................................4
3.2 Environmental regulations in Europe .........................................................................4
3.3 Power market and environmental regulations in (South) Africa..................................5
FGD TECHNOLOGIES...................................................................................................7
4.1 Overview and comparison of different FGD technology ............................................7
4.2 Main questions related to FGD plants ........................................................................7
4.3 Dry FGD technology .................................................................................................9
4.4 Semidry FGD technology ..........................................................................................9
4.4.1 Spray dry absorption (SDA) ................................................................................9
4.4.2 Circulating dry scrubber (CDS) ......................................................................... 10
4.5 Wet FGD technology ...............................................................................................11
4.5.1 Lime / limestone FGD .......................................................................................11
4.5.2 Seawater FGD ...................................................................................................11
SPECIAL REQUIREMENTS FOR (SOUTH) AFRICA ................................................12
5.1 General ....................................................................................................................12
5.2 Typical FGD plants sizes .........................................................................................12
5.3 Feasibility study ......................................................................................................14
OUTLOOK .................................................................................................................... 15
BIBLIOGRAPHY ..........................................................................................................16
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technical track/session 7 - emission control technologies
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2 ABSTRACT
Along with hydro power, coal will remain one of the most important sources of energy
in Africa for the foreseeable future. Coal does however bring with it the price of negative
environmental impact. This necessitates further installations and the continuous improvement
in the efficiency of de-dusting, denitrification and desulphurization equipment used on coalfired plant, as emission limits become increasingly stricter.
Flue gas desulphurization (FGD) technologies were mainly developed in the 1970’s and
‘80’s in Europe (Germany), America (US) and Asia (Japan). Different types of FGD
technologies have emerged over time as a result, an overview of which will be presented in
this paper.
The most widely installed FGD technology throughout the world is currently wet
limestone desulphurization (WFGD). In order to fulfil the requirements of ever stricter
emissions legislation, wet ESPs for SO3 and dust removal need to be installed downstream of
a WFGD. This arrangement has already been implemented in a number of power plants and
has demonstrated a significant increase in capital and operation costs.
Semi-dry FGD technology, based on circulating dry scrubbing (CDS), has now been
further developed and is proving to be highly effective in meeting today’s (and future
stronger) emission requirements. Two major advantages of this technology are the total
removal of SO3 and the high removal efficiency for mercury without the addition of activated
carbon. To ensure that particulate emissions are sufficiently low, a bag filter is installed
downstream of the CDS.
This paper presents a general overview of different FGD technologies including their
advantages and disadvantages. Furthermore this paper will highlight the considerable
experience which has been gained from power plants and international plant designers over
the last 20 years. This paper is intended to be informative when decisions regarding the future
implementation of FGD in Africa are made.
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3 INTRODUCTION
3.1 Worldwide status of air quality
First world industrial development over the past 50 years has seen dramatic increases of
gaseous emissions to atmosphere worldwide, and the more recent growth in emerging
economies augments this considerably. SOX or oxides of sulphur have been identified as a
particularly problematic gaseous emission, not only detrimental to health, but also a major
contributor to negative environmental impacts such as acid rain. Countries including
Germany, the USA and Japan have been proactive in the reduction of SO X emissions through
FGD since the early 1970’s, all the while improving technologies and efficiencies to suit
increasingly strict emissions legislation.
FGD is now a common occurrence on all power stations in Western, developed
countries. The 1990’s has seen the spread of FGD throughout Eastern Europe and Brazil,
Russia, India and China (BRIC). China has taken the lead in the application of FGD on coalfired power stations, having retrofitted FGD into most existing stations, and equipped all new
plant with FGD. In China alone nearly 900,000 MWel worth of power production had been
fitted with FGD by 2010. [1].
This need for FGD, together with the need for reduction in NOx, PM 2.5 and CO2 is
simply indicative of the extent to which power production is based on the combustion of coal
throughout the world. The table below shows the production, consumption, resources and
capabilities of the top ten emitters in the world, accounting for about 90% of global emissions
as a result of coal combustion. [2], [3].
country
China
US
India
Australia
Indonesia
Russia
South Africa
Kazakhstan
Columbia
Poland
production
3,725
835
612
441
411
287
253
109
89
73
no
1
2
3
4
5
6
7
8
9
10
consumption
4,010
757
826
Japan
South Korea
160
178
85
Ukraine
74
no
1
3
2
4
7
6
5
8
10
9
reserves
124,059
222,641
85,562
62,095
17,394
69,634
9,893
25,605
Ukraine
16,203
No
2
1
3
5
8
4
10
7
6
9
resources
5,338,613
6,457,688
174,981
1,536,660
Great Britain
2,658,281
203,667
123,090
Canada
162,709
no
2
1
8
4
6
3
5
10
7
9
Production, consumption, resources and capability of hard coal (2014; Mio. t)
3.2 Environmental regulations in Europe
The “Large Combustion Plant Directive” (LCPD) was developed in Europe and later
became the “Industrial Emission Directive” (IED) no. 2010/75/EU, on 17th Dec 2010,
effective from the 6th January 2011 [4]. EU regulations will continue to focus on decreasing
air pollution levels burning different fuels over the coming years. Recently the EU conference
“LCP BREF review – final TWG meeting” was held in Seville for final discussions, defining
the new, more stringent, environmental regulations, which will be valid in all EU countries in
the near future [5].
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3.3 Power market and environmental regulations in (South) Africa
The general environmental regulations for different countries in Africa aren’t well
known outside of those countries, and are poorly published. Particulate emission control,
mostly ESP, is the norm, while FGD is seen as the future, beginning now. It is assumed that
current clean gas values for SO2 will be based on Europe’s IED of 2011.
The power mix in Africa varies depending on the resources of the country. The estimate
from the International Energy Agency (IEA) for all of Africa for electricity is:
· 40% from coal
· 30% from natural gas
· 15% from hydro
· 12% from oil
·
3% from biofuels, wind and solar based.
The figure below reveals how the Republic of South Africa hosts almost all of the
continents coal applications while North Africa generates its electricity primarily with gas and
oil. Excluding South and North Africa hydropower then becomes the dominant electricity
source for the rest of Africa´s 780 million people. If the electricity consumption per person in
Africa is compared to the rest of the world (500 vs 2,500 kWh) this is only 20%. Excluding
North and South Africa the value drops to only 180 kWh. This means that about 80% of
Africa people use less than 7% of the world’s power average or only 1.5% that of the average
North American citizen. [6].
Primary energy used in power production
Relationship between electricity use and GDP
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Therefore, it is anticipated that power production in Africa will increase at least fast as
the world average increase over the coming years. Renewable energy (hydro, solar and wind)
will play a large role in this increase with past and future trends from 2005 to 2020 suggesting
an increase from 0.2% to 10.8% of total supply. However, in South Africa coal-fired thermal
power will remain dominant (2005: 90.3%=38,938 MWel; forecast 2020: 81%=54,122 MWel).
This is clearly illustrated below [7].
Development of main power sources and total installed capacity in South Africa
Minimum emission standards for South Africa are based on the National Environmental
Management/Air Quality Act, 2004 (act. no. 39 of 2004) published in Government Notice
no. 893, Gazette No. 37054 dated 22 November 2013. The given maximum emission allowed
for combustion installations ≥50 MWel burning solid fuel are shown in the following table [8].
Pollutant
Particulate matter
SO2
NOX (as NO2)
Emission limit values in mg/Nm3 at 10 vol.-% O2
New plants
Existing plants
(present to 1 April 2020)
(from 1 April 2015)
≤ 50
≤ 100
≤ 500
≤ 3,500 (≤ 500 from 2020)
≤ 750
≤ 1,100
Governmental emission limits valid in South Africa
This short look to the power market of Africa – mainly South Africa - and the
knowledge of environmental protection issues is indicative of a marked increase in new and
retrofit FGD Plant to be built over the next 6 years. Africa will reap the benefit of the
experience gathered by plant builders and users in Europe, Japan and the USA over the past
40 years and can look forward to a relatively smooth implementation of FGD.
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4 FGD TECHNOLOGIES
4.1 Overview and comparison of different FGD technology
The illustration below shows the different and applicable types of FGD technology in
use today. By far the most common is (non-regenerative) wet limestone FGD which could
produce saleable gypsum as a by-product. About 88% of worldwide FGD installations
(related to installed power in MWel) are based on this type of technology followed with about
9% by (non-regenerative) semi-dry FGD technology, using spray dry absorption (SDA) or
circulating dry scrubber (CDS) technology. All the other “exotic” FGD technologies like
(regenerative) activated carbon or Wellman-Lord make up the balance of about 3%. [9].
Based on a majority usage of FGD technologies, this paper focuses on semidry
(SDA/CDS) and wet (limestone/seawater) FGD technologies only.
Different main types of FGD technology
4.2 Main questions related to FGD plants
At the inception of every FGD project the questions about the design parameters and
pre-existing conditions should be clear and answered regardless of the choice of FGD plant.
These questions must however be dealt with in such a way as to give a clear indication of the
most suitable plant type. The table below is indicative of the information required before an
FGD project is contemplated.
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No.
Basic conditions
1
Raw gas components
2
Clean gas requirements
3
Clean gas temperature
4
Type of Source / fuel
5
Availability and quality of absorbent
6
Requirements for FGD product
7
Preferences to existing technologies
8
Place requirements
9
Retrofit / use of existing units
10
Dedusting requirements
11
Project time schedule
12
Investment costs
13
Operation costs
14
Maintenance costs
15
Availability
Comments
Additional to SO2 content all the other components (i.e. SO3,
HCl, HF, heavy metals, dust) are important to know.
Based on the raw gas data and the given legislative emission
limits the removal efficiencies can be specified and FGD
process incl. technical equipment could be calculated.
Required clean gas temperature can result in special equipment (e.g. GGH) being used and will influence the material
used and the whole FGD concept (e.g. use of existing stacks,
wet stack, water consumption) and investment cost for sure.
Type of source/fuel is the basis for the raw gas components.
Depending on the FGD technology different absorbents are
necessary (limestone, seawater, lime, hydrated lime). The
availability, quality, consumption and price of absorbent can
influence the decision for a special type of FGD technology.
One of the most important questions to be clarified is the use
of generated FGD by-product. Is there a market for a special
type of FGD by-product? Are there additional costs for
further FGD by-product preparation? Is there separate
removal of filter dust required?
Are there special preferences by the client, public authority or
others? The basis for preferences can be very difficult.
Should the FGD project to be built on a so-called green field
(no limited space, optimal arrangement) or it’s a retrofit
project? What are the special boundary conditions, connecting
points etc.?
See 7. above. Are there special existing units, buildings,
equipment (filter) which should be used?
This is very important for the decision of wet or dry/semidry
FGD technology. Upstream of wet FGD the flue gas stream
should be de-dusted as there is a very limited possibility to
remove dust in a wet FGD. Upstream of a dry/semidry FGD
flue gas can include dust coming from the boiler (normal PC
or CFB boiler) or dust coming from an older filter system
downstream an existing boiler (no need of filter retrofit!).
This is because a new filter system will be included in a
dry/semidry FGD plant in any case.
Based on the more difficult and complex wet limestone FGD
technology, as compared to dry/semidry FGD the time for
project execution of wet limestone FGD will be normally
longer then for dry/semidry FGD.
Based on points 3, 6, 10 and 11 the investment costs should
be normally higher for the wet limestone FGD technology
compared with the dry/semidry FGD technology.
Depending on the different molar ratios of FGD technologies
resulting consumption data, prices of different absorbent
types and the commercial calculations, the resultant breakeven point can vary.
Based on the higher complexity and difficulty of the wet
limestone FGD technology maintenance costs will be higher
than for a dry/semidry FGD technology.
Comparable for all FGD technologies ≥ 98 %.
Main questions related to FGD plants
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4.3 Dry FGD technology
Based on its noted characteristics, application of dry FGD technology isn’t widely used and
application is limited. Depending on the feeding point, which can be special regions in the
boiler itself, flue gas duct or a downstream filter, different types of sorbent (limestone, lime or
hydrated lime) can be used. As noted earlier molar ratios are high with very limited removal
efficiencies. For this reason the installation of dry type FGD plants is on the decrease
especially given stricter environmental regulations all over the world, but there may still be a
special and limited market for applications in (South) Africa.
4.4 Semidry FGD technology
4.4.1 Spray dry absorption (SDA)
Especially in the USA and other American countries, FGD plants based on SDA technology
have been extensively used. An absorbent suspension of hydrated lime is used. Controlled
injection of the lime suspension is done by specialised spray nozzles or fast rotating
equipment which both requires a relatively high level of maintenance. Additionally, based on
chemical reactions and stoichiometry, the removal efficiency is limited with a medium level
of molar ratio. Therefore the demand for this type of technology has waned in recent years.
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4.4.2 Circulating dry scrubber (CDS)
Conversely, and as opposed to SDAs, an increased demand for semi-dry CDS
technology has been observed. The development of flue gas cleaning in a circulating dry
scrubber, also well-known as circulating fluidized bed (CFB) FGD, goes back to the early
1970s and its first application in the alumina industry. Research and development
subsequently led to the application of this technology in flue gas desulphurisation (SO2) for
power plants and flue gas cleaning (HCl, HF and SO2) for waste incinerators [10]-[13].
Over time CDS design has evolved and been standardized by most OEMs. The
specific design feature of a CDS is the venturi section, where the flue gas is accelerated. The
water injection area is downstream of the venturi section, while the solids recirculation is
located either upstream or downstream of the venturi section (depending on the OEM).
These days most OEMs of CDS FGD technology offer more or less the same venturi
design, which was developed by Lurgi about 40 years ago. Furthermore the design of the
water injection and solids recirculation has remained more or less unchanged over time.
Back in 2007 though, Hamon Enviroserv started to develop their own computational
fluid dynamics (CFD) simulation tools in order to understand, and especially further improve
upon existing CDS technology. With the support of plant owners and operators at different
sites, the results of the CFD simulation were validated at various loads. The net result of these
simulations was the identification of weak points in the technology and the adoption of
appropriate remedies. These dealt with the problem of high moisture content in the by-product
and the resultant blockages inside the CDS system. In addition the venturi section design was
optimised together with an improved water injection system. These developments are the
basis of Hamon brand name BLUESORP ® used for their semidry CDS FGD technology.
In 2012/2013 these design changes for the venturi section and the water injection
system were implemented at the CDS plant at Plzeňská teplarenská / Czech Republic. The
successful improvement of the plant and other CDS developments had been published
repeatedly [14]-[23]. Based on successive and successful executions of these improvements,
HAMON semidry BLUESORP ® technology now offers a far more reliable and efficient
operation at all boiler loads. During optimisation lime consumption (molar ratio) could be
significantly reduced. CFD as a tool has proved to be the key to the upgrading and
improvement of existing CDS plants and for new plants the installation of a single CDS unit
for multiple boilers up to 700 MWel at no risk.
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4.5 Wet FGD technology
4.5.1 Lime / limestone FGD
As stated previously, wet limestone is the most common installed FGD technology
worldwide, especially for big power plants. FGD plants have been built for up to 1,000 MWel
units, each with absorber diameters of up to 24 m.
Raw gas coming from boiler units is normally de-dusted (mostly by electrostatic
precipitators) and fed into a stack without any desulphurization. Based on stricter regulations
flue gas, especially from coal fired boiler units, has to be desulfurized. During normal
operation, the raw gas is fed via a booster fan to the new absorber, where the raw gas is
saturated and cleaned. In the case of FGD plants being on outage, the ID fan conveys flue gas
to the existing stack (via a bypass duct, if allowed by authorities). Depending on the wet FGD
design, cleaned gas can be discharged directly through a wet stack on the top of the absorber
to the atmosphere (see photo above).
Wet limestone FGD technology is the most used and well known FGD technology
worldwide. Further developments are therefore limited and relate to optimization of SO2
removal and the reduction of operating cost. Special attention is given to CFD simulation
tools as the basis for optimization of the design and the arrangement of different types of
spray nozzles [24]-[29]. The uppermost spray bank is equipped with single directional hollow
cone nozzles spraying in counter flow. The other spray banks are equipped with twin
directional hollow cone nozzles spraying both in counter flow and co-direction. After
scrubbing of the flue gas by the different spray banks, the flue gas passes through a mist
eliminator to reduce the droplet content in the clean gas.
Depending on the FGD design, the resultant gypsum suspension is dewatered, and
depending on the quality, graded for commercial use.
4.5.2 Seawater FGD
Seawater FGD technology is a specialised type of wet FGD which can only (for
obvious reasons) be installed on a country´s coastline. Untreated seawater is used to scrub the
flue gas, taking advantage of seawater’s natural alkalinity in order to neutralise the SO2. Raw
seawater is obtained from the steam turbine condenser outlet. Part of this water is pumped
into the top of absorber tower. Acidified liquid is collected in the absorber pump. It is not
recirculated back (as usual in wet limestone FGD) to the top of the tower, but flows into the
external mixing and aeration basin. Here it is combined with the remainder of the seawater
from the condenser outlet and aerated to reduce the chemical oxygen demand and raise its pH
by driving off carbon dioxide (CO2). The treated liquor is then discharged back to the sea.
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Compared with wet limestone FGD technology the seawater FGD design is relatively
simple but requires special experiences. The absorber is an open spray tower also
incorporating similar spray nozzles to wet FGD. There is a substantial reference list for this
technology [30].
Seawater FGD demand is increasing, especially in the Middle East and Asia
(Indonesia, China, Vietnam) and may yet find a home on coastal coal-fired power stations in
Africa.
5 SPECIAL REQUIREMENTS FOR (SOUTH) AFRICA
5.1 General
Africa, and more specifically South Africa faces a power shortage which, while being
addressed, will see the construction further new power plants. These will be by both state
(Eskom’s Medupi and Kusile Power Stations) and Independent Power Producers (IPPs). New
plants, beginning with Kusile (6 x 800MWel), are being built with FGD in place as required
by legislation. The same legislation will require that existing power plants be retrofitted with
FGD in order to meet “as new” emission limits from 2020 [31]-[33].
The latter will be challenged by the National Water Act (NWA) Act. No. 38 of 1998,
which deals specifically with water usage constraints. Therefore one of the main focus areas
when planning new or retrofit FGD plants for the future will be water consumption. (see
chapter 4.2).
5.2 Typical FGD plants sizes
The table below defines some typical design data and technical information for different
boiler sizes which is of importance for future FGD projects in Africa. Depending on the type
of fuel and the industrial sector (mining, petrochemical, iron and steel, pulp and paper as well
as power and energy) the volume flows and flue gas parameters like SO2, HCl, HF, dust,
heavy metals etc. will be different. The numbers in the following table are therefore indicative
only.
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Parameter
unit
data
Example
①
②
③
Boiler size
MWel
100
300
600
Raw gas data for FGD process calculations
Volume flow Mio Nm3/h
0.4
1.0
1.8
Temperature
°C
145
O2 content
vol.-%
4.5
H2O content
vol.-%
8.8
SO2 content
mg/Nm3 dry
5,000
HCl content
mg/Nm3 dry
100
HF content
mg/Nm3 dry
10
Dust content
mg/Nm3 dry
50
Dust content
mg/Nm3 dry
comments
④
800
2.5
wet flue gas
wet, act. O2
refer to act. O2
refer to act. O2
refer to act. O2
with filter downstream boiler
(retrofit semidry and wet FGD)
without filter downstream boiler
(new construction; CDS only)
20,000
Clean gas data / governmental requirements / emission limits
SO2 content
mg/Nm3 dry
500
HCl content
mg/Nm3 dry
10
HF content
mg/Nm3 dry
5
Dust content
mg/Nm3 dry
50
refer to 6 vol.-% O2
refer to 6 vol.-% O2
refer to 6 vol.-% O2
refer to 6 vol.-% O2
With these assumed but typical raw flue gas data for different boiler sizes, process design
calculations have been made for semidry CDS and wet limestone FGD technology.
The table below shows the results obtained for semidry CDS FGD technology. Purity of
lime is assumed to be ≥ 95% CaO with a reactivity time of t60 ≤ 4 min.
Parameter
unit
data
Example
①
②
③
Boiler size
MWel
100
300
600
Main results for semidry CDS FGD technology
Volume flow
Mio Nm3/h 0.436 1.073 1.922
Temperature
°C
77
H2O content
vol.-%
14.1
comments
④
800
2.665
clean flue gas; wet
at ID fan outlet
at ID fan outlet
lime (CaO)
FGD product
t/h
t/h
2.1
4.5
5.1
11
9.3
20
12.9
27.8
with filter downstream boiler (retrofit)
lime (CaO)
FGD product
t/h
t/h
2.2
12.5
5.6
31.3
10
56.3
13.9
78.2
without filter downstream boiler
(new construction)
water
waste water
m3/h
m3/h
21
52
94
130
including dry lime hydration
waste water free FGD technology
Mio USD
12.8
24
30.4
budgetary; engineering and delivery only;
civil part and erection locally
investment cost
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The table below shows the key results obtained for wet limestone FGD technology.
Process calculations are based on an assumed limestone purity of ≥ 95% CaCO3 with 1.5%
MgCO3 and 3.5% inert substances and a maximum of 30,000 ppm dissolved Chlorides of
absorber slurry.
Parameter
unit
data
Example
①
②
③
Boiler size
MWel
100
300
600
Main results for wet limestone FGD technology
Volume flow
Mio Nm3/h 0.43 1.075 1.935
Temperature
°C
53.3
H2O content
vol.-%
14.3
limestone
FGD gypsum
water
waste water
Investment cost
Comments
④
800
2.687
clean flue gas; wet
at absorber outlet
at absorber outlet
t/h
t/h
3
5.4
7.5
13.6
13.5
24.5
18.7
34
CaCO3; purity 95 %
with filter downstream boiler
m3/h
m3/h
24
1.3
60
3.1
107
5.6
150
7.8
lower (but more expensive) with GGH
influenced by different parameters
Mio USD
16
20
30
38
budgetary; engineering and delivery only;
civil part and erection locally
5.3 Feasibility study
As discussed in this paper thus far, and shown in the above mentioned tables there are a
lot of different pre-conditions which could influence the FGD design including consumption
figures. Based on the selected FGD technology resp. FGD concept and associated water and
reagent consumption, capital and operation cost could vary greatly. Therefore in anticipation
of FGD projects in the future, feasibility studies are essential to find the most economical
solution for each project.
Feasibility studies should highlight the most economical FGD type for a specific project.
Studies should include, but not be limited to the following:
·
·
·
·
·
·
·
·
·
Consumption of absorbents (different types)
Consumption of water
Consumption of power
Produced amount of FGD product in required quality / composition
Electrical consumer and measurement lists
Arrangement drawings including requirements for further possible execution
Definition of battery limits, scope of supply and exclusions
Investment costs based on real design
Operation costs based on a.m. data and local prices
Hamon Enviroserv has prepared such studies for differing FGD projects. Power plants
were visited and pre-conditions, especially battery limits for future FGD installations, were
discussed with interested parties and operators. Processes to be compared were calculated and
possible plant arrangements prepared including all the auxiliary equipment needed for the
different FGD technologies.
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Based on the arrangement designs, process parameters and masses were calculated.
Price calculations for FGD capital investment were prepared based on offers from specialised
sub-suppliers, world-wide sourced prices for steel and other materials and based on available
knowledge. Price calculations for operation costs for different FGD technologies were done
based on calculated consumption figures and local prices. The final summarized prices for
investment and operation costs have been compared and shown in different diagrams.
Financial conditions like interest rates, estimated lifetime for FGD, yearly operating time and
other special conditions are considered. Depending on project conditions there will be a
break-even point after some years. This result is valid for the specific project only, any other
project has to be discussed and calculated with their own non-reversible preconditions.
6 OUTLOOK
With the continuous requirement for the reduction of atmospheric emissions worldwide,
the necessity for increased efficiency of flue gas cleaning systems is a given.
This paper is intended to show that, depending on the locations and local conditions the
semidry (SDA/CDS) and wet (limestone/seawater) FGD technologies combine all
requirements needed to fulfil the current needs, and more importantly the needs of the future
for FGD in Africa.
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7 BIBLIOGRAPHY
[1] McIlvaine, Newsletter “FGD & DeNOx Insights”, No. 40, November 2014
[2] Coal/tables and graphics, Wikipedia, December 2015
[3] World coal market review, International Energy Agency (IEA), 2015
[4] Industrial Emissions Directive (IED) No. 2010/75/EU published in Official Journal of
European Union on 17th December 2010, came into force on 6th January 2011
[5] LCP BREF review – final TWG meeting;
European IPPC Bureau, Seville, 1-5/8-9 June 2015
[6] A fast track to African power
Power Engineering International, October 2012
[7] Africa focus, Renewables set to be the big winner in South Africa
Power Engineering International, October 2012
[8] Department of Environmental Affairs, Government Notice No. 893 dated 22nd Nov 2013
Air Quality Act, 2004 (Act. No. 39 of 2004)
[9] McIlvaine, World FGD market, October 2013
[10] Sauer, H.; Sparwald, V.; Wendt, G.:
Betriebserfahrungen mit der Abgasreinigungsanlage nach dem System VAW/Lurgi,
Erzmetall 35, No. 12, 1982, pp. 605-609
[11] Sauer, H.; Anders, R.:
Betriebserfahrungen mit der trockenen Rauchgasentschwefelung (System ZWS)
im Braunkohle-Kraftwerk Borken
VGB Kraftwerkstechnik 69, vol. 10, 1989, pp. 1018-1023
[12] Sauer H.; Baege, R.; Herden, H.:
New Aspects of CFB Technology for Flue Gas Cleaning
Power-Gen Europe, Milan, 2002
[13] Sauer, H.; Leuschke, F.; Baege, R.; Yi, J.:
What is possible to achieve on flue gas cleaning using the CFB FGD technology?
8th International Conference on CFB, Hangzhou, China, 2005
[14] Baege, R.; Feldkamp, M.:
Long-term experience of plant operators with dry flue gas cleaning in a circulating
fluidized bed (CFB)
4th Symposium “Dry flue gas cleaning”,
Essen (Germany), November 13-14, 2008
19-21 July 2016, Johannesburg
technical track/session 7 - emission control technologies
page 16 of 18
[15] Baege, R.; Feldkamp, M.; Dickamp, M.; Moser, C.:
Long-term experience and large-scale application of CFB (CDS) FGD technology
Power-Gen International
Las Vegas (USA), December 8-10, 2009
[16] Dongres, Z.; Knotek, J.; Baege, R.; Grafahrend, F.; Johnson, B.; Redinger, K.:
Modification and optimization of an existing CDS FGC system for biomass co-firing
MEGA Symposium
Baltimore (USA), August 30 – September 2, 2010
[17] Baege, R.; Dickamp, M.; Dongres, Z.; Knotek, J.:
Modification and optimization of an existing CDS FGC for biomass co-firing
Coal Gen Europe, Praha (CZ), February 15-17, 2011
[18] Feldkamp, M.; Dickamp, M.; Dongres, Z.; Chenevey, J.; Redinger, K.:
Modification and optimization of an installed CDS FGD system
Dry Scrubber Conference, Providence (USA), September 18-20, 2012
[19] Gayheart, J.W.; Feldkamp, M.:
Physical flow modelling (PFM) and computational fluid dynamics (CFD) simulation to
enhance the CDS technology
MEGA Symposium, Baltimore (USA), August 19-21, 2014
[20] Feldkamp, M.; Neuhaus, T.:
Modification and Optimization of installed CDS FGD System
Dry Scrubber Conference
Providence (USA), October, 2014
[21] Baege, R.; Feldkamp, M.; Neuhaus, T.
Operation experiences from an optimized existing semidry CDS FGD in combination
with a converted ESP into a hybrid fabric filter
VGB Workshop „Flue Gas Cleaning 2015“, Istanbul (Turkey), May 6-7, 2015
[22] Baege, R.; Moser, C.:
Development and large-scale application of CFB (CDS) FGD technology
Power-Gen Asia
Bangkok (Thailand), September 1-3, 2015
[23] Feldkamp, M.:
Operation experience with a new build two venturi CDS FGD system with direct burned
lime injection
Dry Scrubber Conference
Rapid City (USA), September 15-17, 2015
[24] Kleeberg, M.:
Retrofit of an optimized FGD system at Plzeňská energetiká
FGD days Carmeuse
Brasov (Romania), May 6-7, 2010
19-21 July 2016, Johannesburg
technical track/session 7 - emission control technologies
page 17 of 18
[25] Knoche, B.; Decker, M.:
Preparing existing wet FGD´s for new EU legislation
Coal-Gen Europe
Warszawa (Poland), February 14-16, 2012
[26] Feldkamp, M.; Kerber, H.-G.:
Optimierung der Rauchgasreinigung im Kraftwerk Plomin mit Hilfe der CFD Simulation
VDI-Fachkonferenz REA, SCR und Entstaubungsanlagen in Großkraftwerken
Düsseldorf (Germany), December 5-6, 2012
[27] Bautsch, C.:
Design and Simulation of ESP and FGD at O Mon power plant unit 2
VGB Workshop “Flue Gas Cleaning 2014”
Marseille, (France), May 21-22, 2014
[28] Bautsch, C.; Knoche, B.
Design and simulation of FGD at Bolu Gaynuk power plant
VGB Workshop „Flue Gas Cleaning 2015“
Istanbul (Turkey), May 6-7, 2015
[29] Bautsch, C.; Feldkamp, M.; Baege, R.
Simulationsgestützte Effizienzsteigerung von Rauchgasreinigungssystemen
11. VDI-Fachkonferenz „REA-, SCR- und Entstaubungsanlagen in Großkraftwerken“
Düsseldorf (Germany), November 25-26, 2015
[30] Grafahrend, F.; Bautsch, C.; Yudatoma, Y.:
Long-term experiences and development of seawater FGD technology
Power-Gen Middle East
Doha (Qatar), February 6-8, 2012
[31] Peltier, R.:
Camden Power Station, Mpumalanga Province, South Africa
Power │October 2014, pages 22-23
[32] Ramahali, K.:
Eskom´s experience in wet flue gas desulphurization (WFGD) design and construction
VGB PowerTech 10 │2014, pages 50-55
[33] Koko, M.; Singh, Y.:
Overview of the Eskom and South African new built program
VGB PowerTech 1/2 │2016
19-21 July 2016, Johannesburg
technical track/session 7 - emission control technologies
page 18 of 18