Prabin K. Sharma et al.: Use of Acetylene as an Alternative Fuel in IC Engine
Use of Acetylene as an Alternative Fuel in IC Engine
Prabin K. Sharma, Harihar Kuinkel*, Praveen Shrestha, Suman Poudel
Abstract— This project leads to the idea of using acetylene
gas in the internal combustion engine such that it reduces the
demand of the petroleum products that is going to be extinct in
near future. It includes about the emissions of harmful gases
that can be reduced by the use of acetylene instead of
petroleum products. Various fuels have been tested on IC
engines for their suitability as alternate fuels. Expect few
alcohols, CNG and LPG, not many fuels have been found to be
matched with IC Engines requirements .Thus this project is an
attempt for the use of an alternative resource such that it can
prove to be useful for the peoples in near future.5
Index terms─ Alternative fuel, emission, thermodynamic
approach, exhaust analysis, comparison, efficiency.
As acetylene is colorless gas and is highly combustible
with high flame speed and fast energy release, it can be used
as alternative fuel in IC engines. It has a very wide
flammability range and minimum ignition energy required
for ignition. Furthermore comparing with various other fuel
properties, acetylene proved good to be used in internal
combustion engines.
TABLE I
COMPARISON WITH OTHER FUELS
Physical and Combustion
Properties of fuels
Acetylene
Hydrogen
Diesel
Fuel
C 2 H2
H2
C8 – C20
3
I. INTRODUCTION
Density kg/m (At 1 atm
& 20 o C)
1.092
0.08
840
N the present context, the world is facing difficulties
with the crisis of fossil fuel depletion and environmental
degradation. Conventional hydrocarbon fuels used by
internal combustion engines, which continue to dominate
many fields like transportation, agriculture, and power
generation leads to pollutants like HC (hydrocarbons), SOx
(Sulphur oxides), and particulates which are highly harmful
to human health. CO2 from Greenhouse gas increases global
warming. Promising alternate fuels for internal combustion
engines are natural gas, liquefied petroleum gas (LPG),
hydrogen, acetylene, producer gas, alcohols, and vegetable
oils. Among these fuels, there has been a considerable effort
in the world to develop and introduce alternative gaseous
fuels to replace conventional fuel by partial replacement or
by total replacement. Many of the gaseous fuels can be
obtained from renewable sources. They have a high selfignition temperature; and hence are excellent spark ignition
engine fuels. And among these wide area of research, use of
acetylene as internal combustion source in engine could be
most appropriate field to research as alternative source of
fuel and can be used as the synthetic fuel for transportation.
Auto ignition temperature
(oC)
305
572
257
Stoichiometric air fuel
ratio, (kg/kg)
13.2
34.3
14.5
Flammability Limits
(Volume %)
2.5 – 81
4 – 74.5
0.6 – 5.5
Flammability Limits
(Equivalent ratio)
0.3 – 9.6
0.1 – 6.9
------
Lower Calorific Value
(kJ/kg)
48,225
1,20,000
42,500
Lower Calorific Value
(kJ/m3)
50,636
9600
-------
Max deflagration speed
(m/sec)
1.5
3.5
0.3
Ignition energy (MJ)
0.019
0.02
--------
Lower Heating value of
Stoichiometric mixture
(kJ/kg)
3396
3399
2930
I
The principal objective and advantages of the present
project include: providing a fuel comprising acetylene as a
primary fuel for an internal combustion engine; providing
such a fuel including a secondary fuel for eliminating knock
which might otherwise arise from the acetylene.
II. ABOUT ACETYLENE
Acetylene is the colorless gas with garlic smell produced
from the calcium carbide , which is obtained from
calcium carbonate . Further the calcium carbonate is
heated in lime kiln at about 8250c which forms calcium
oxides (lime) liberating . Calcium oxide is then heated in
electric furnace with coke to produce calcium carbide finally
calcium carbide is hydrolyzed producing acetylene.
*Corresponding author: [email protected]
Prabin K. Sharma, Harihar Kuinkel, and Praveen Shrestha are with the
Department of Mechanical Engineering , Kathmandu University
Suman Poudel is with the Department of Environmental Engineering ,
Kathmandu University
Rentech Symposium Compendium, Volume 1, March 2012
III. OVERVIEW OF PROJECT
Step 1: The first step involves the production of
acetylene gas through the Calcium Carbide reacting with
water in the reaction tank.
CaC2+2H2O
C2H2+Ca (OH)2
The reaction tank constitutes two chambers:
• In first (upper) chamber the water is kept.
• In second (lower) chamber the calcium carbide is
kept.
The water from the first chamber is released in such a
way to proceed the reaction spontaneously. The water is
passed through the control valve. In the second chamber the
calcium carbide is kept in desirable amount to react with
water. Through second chamber a valve is connected to the
storage tank where the gas produced during reaction is
stored.
19
Prabin K. Sharma et al.:: Use of Acetylene as an Alternative Fuel in IC Engine
Step 2: In this step the acetylene gas is stored in the
storage tank and the pressure is measured by the pressure
gauge.
this phenomenon is not mentioned here but we can simply
compare the results from the calculated values.
TABLE II
ADIABATIC FLAME TEMPERATURE COMPARISON
Acetylene
2908.120K
Gasoline
2068.980K
Acetylene with alcohol
2569.540K
From above results we can say that alcohol is to be
introduced so as to reduce the temperature inside the
combustion chamber. For start up and operation of the
engine, two stages are involved: first the engine is started by
secondary fuel (use of ethyl alcohol
alcohol in this project). And
after certain warmwarm-up
up period the second stage involves
operating the engine by the use of primary fuel (acetylene)
to generate power output from the engine.
Fig. 1: Experimental Setup
In this step the produced gas is stored and is passed
through the pipes. Here the gas is stored to avoid moisture
and the gas stored in storage tank is provided pressure
through pressure gauge so the gas is of high concentration.
Step 3: The gas is passed
passed in the pipes in a very
sophisticated manner and then pipe is joined in the
carburetor fitted with the filter, this then filters the air and
then combines with petrol as secondary fuel which is added
in very few amount ( in about 10 to 15%) to prevent
knocking
nocking for smooth operation of an engine. Then the
mixture is passed in the engine.
F
Fig
ig. 3: Gas Injection
njection Valve
Fig. 4: Time Manifold Control Unit
IV. SOME BASIC THERMODYNAMIC EVALUATION OF
THE PROJECT
A. Stiochiometric Air/Fuel Ratio
atio Calculation
alculation
Fig 2: Overview of the Project
Fig.
III. INTRODUCTION OF SECONDARY FUEL
We can illustrate that introduction of secondary fuel is an
essential part of this project as introducing alcohol
( helps to reduce the adiabatic
flame temperature in the combustion process which leads to
avoid the auto ignition and and knocking. The illustration of
Rentech Symposium Compendium, Volume 1, March 2012
The main governing equation of the combustion is
described below for the calculation of air fuel ratioratio
4# 3.773 - → 2 3.773 4 !'
!
(
+
)* , #*.../0.)1
#
##)..2))*).220 3
( 13.28 #7 ( 1
20
Prabin K. Sharma et al.: Use of Acetylene as an Alternative Fuel in IC Engine
!0')8.91
(
+
)* , #*.../0.)1
#).2))*).220 3
( 14.61 #7 ( 1.87
B. Comparison of maximum useful work of acetylene and
gasoline
∆<=>? ≤ −#∆ − B∆C
∆<=>? ≤ −# − BCD EF,HF − # − BCI EF,HF (
#∆J KL,DL
Now, for the calculation of Gibbs free energy of the
acetylene for complete combustion i.e. for equivalence ratio
(ф≤1) we have the followings.
2 → 2 + #∆J KL,DL = #−2 × 394360 − 228590 − 209170 =
43.326 PQ/ST
#∆J KL,DL
UVWXYZ[
= −45.7PQ/ST
This illustrates that the maximum useful work of
acetylene and gasoline is quite comparable.
# = 4.16, = 7.406 , = 3.84 , ] = 0.074C8H14.96
# = 1.27, = 0.896 , = 0.73 , ] = 0.104C2H2
TABLE III
EXHAUST GAS COMPOSITION PER UNIT MOLE
Gasoline#0 )8.91 0.0695
0.1239
0.0642
0.00124
0.7410
-
Acetylene# 0.0804
0.720
0.058
0.00836
0.7586
-
(Note that the carbon monoxide emission for gasoline is greater than that of
acetylene)
VI. ENVIRONMENTAL ASPECTS
A. Total Emissions in Metric Tons
The molecular weight of acetylene is 26 with two carbon
atoms (C2H2 gas density = 0.068 lb/ft3 typically the Material
and Safety Data sheet will provide this detail of information)
while the molecular weight of CO2 is 44 with one carbon
atom. Given that each mole of acetylene, under complete
combustion, will create two moles of CO2 (i.e., each pound
of acetylene combusted will produce 3.38 pounds of CO2
(2x44/26)). Use the following conversion calculations to
derive an emission factor for acetylene:
2.210 X
) abYa c[[d !e 'e
×
8.1U
) X
=
2.08U
) abYa c[[d Wc !e 'e
30.845T
1
×
1 = f 26.04
1 gh 1.185 gh =
1 = f f 2.210 X
8.1U
2.08U
×
=
) abYa c[[d !e 'e
2.08U
) abYa c[[d !e 'e
Fig. 5: Comparison of Thermal Efficiency by Adiabatic Constant
) X
× 1.28
0 )8.91 +
∅
# + 3.773- → + + +
] + 44.295- (T=1700K)
).
# + 3.773- → + + +
+
∅
] + 9.4325-
log)2 SD =8.011+4.699-12.180=0.530
Where,
SD =3.338 (Equilibrium constant) from JANAF table.
=
).)0 >WX !e 'e
) abYa c[[d Wc !e 'e
2 gh 2.370 gh 1.185 gh ×
=
1 = f 1 gh 1 = f f ..2 >WX !ie
88.2)
)28.28 U !ie
×
=
)28.28U!ie
))..8
)
) >WX ! '
e e
) abYa c[[d !e 'e
V. EXHAUST GAS COMPOSITION BY THERMODYNAMIC
APPROACH FOR RICH MIXTURE (∅ = 1.2
) abYa c[[d Wc !e 'e
) abYa c[[d !e 'e
×
) >WX !ie
) abYa c[[d Wc !e 'e
) >[djYa dWZ
=
)2k
).82×)2l, >.dWZ !ie
) abYa c[[d Wc !e 'e
Acetylene consumed#cubic feet ×
Acetylene Emission Factor ).82×)2l, >[djYa dWZ ! ie
) abYa c[[d Wc !e 'e
Total emissions #metric tons .
=
The result obtained from this calculation illustrates that
the amount of CO2 emitted is fairly minimum and other
emissions like NOx, SOx are highly negligible compared to
CO2. This indicates that acetylene can be relatively more
environmental friendly than gasoline.
By balancing the no. of moles we get the following
quadratic function.
2.38 − 36.701 + 105.830 = 0
= 3.83
Rentech Symposium Compendium, Volume 1, March 2012
21
Prabin K. Sharma et al.: Use of Acetylene as an Alternative Fuel in IC Engine
B. Ozone Layer Depletion (Photochemical Ozone
Creation Potential (POCP))
Despite playing a protective role in the stratosphere, at
ground-level ozone is classified as a damaging trace gas.
Photochemical ozone production in the troposphere, also
known as summer smog, is suspected to damage vegetation
and material. High concentrations of ozone are toxic to
humans.
Radiation from the sun and the presence of nitrogen
oxides and hydrocarbons incur complex chemical reactions,
producing aggressive reaction products, one of which is
ozone. Nitrogen oxides alone do not cause high ozone
concentration levels. Here are some of the comparisons of
POPC between several compounds.
TABLE IV
POPC COMPARISON OF DIFFERENT COMPOUNDS
This paper include the fact that acetylene can be a good
fuel for the country like Nepal where calcium carbonate are
abundant in nature as it is already discussed above. Despite
of being, good fuel for IC engine, there are some of the
control measures and safety precautions that are involved in
gas phase reactions that can cause serious damages.
ACKNOWLEDGEMENT
Accomplishment of this project was indeed very
challenging and we overcame it with the help of department
of Mechanical engineering at Kathmandu University. We
would like to thank our coordinator Dr. Bibek Baral for
helping us succeed this project and also would like to thank
Mr. Suraj Pandey for helping us in our queries .We are also
very thankful to our friends who helped us in the entire
project.
REFERENCES
[1]
[2]
[3]
J. B. Heywood, Internal Combustion Engine
Fundamentals,
McGraw-Hill, Inc., New York, 1988.
Chigier N (1981) "Energy, Combustion and Environment", McGraw
Hill
J. Wulff, W.Hulett, L. Sunggyu, “Internal combustion system using
acetylene fuel”. United States Patent No 6076487.
[4]
N. Swami, J.M. Mallikarjuna, A. Ramesh, “HCCI engine operation
with acetylene the fuel”. SAE paper no 2008-28-0032.
[5]
V.M.S. Ashok, N.I. Khan, “Experimental investigation on use of
welding gas (Acetylene) on SI Engine”. Proceedings of AER
Conference, IIT, 2006. [6] Ganesan V. Internal combustion engine.
3rd ed. Singapore: McGraw Hill Book Company; 2007.
BIOGRAPHIES
Prabin Kumar Sharma is studying Bachelors in Mechanical Engineering
(IIIYr/Ist sem) at Kathmandu University.
Harihar Kuinkel is studying Bachelors in Mechanical Engineering (IIIYr/Ist
sem) at Kathmandu University.
Note that acetylene has very low POPC that implies it has low reactivity
towards OH- radical.
The total emissions vary greatly with fuel structure. Two
factors have been identified for this large variation: diffusion
and reactivity. Diffusion of fuel molecules from boundary
layers near the cylinder wall into the hot core gas causing
partial oxidation of this fuel may be a significant source of
burn-up of HC species exiting crevices during the expansion
stroke. Thus, higher molecular weight fuels, which diffuse
more slowly, tend to exhibit higher emissions.
Praveen Shrestha is studying Bachelors in Mechanical Engineering
(IIIYr/Ist sem) at Kathmandu University.
Suman Poudel is studying Bachelors in Environmental Engineering
(IIIYr/Ist sem) at Kathmandu University.
VII. ABUNDANCE OF CALCIUM CARBONATE IN NEPAL
As mentioned earlier, acetylene is the outcome of
calcium carbide. Similarly, calcium carbide is the outcome
of calcium carbonate. According to Krishna Dev Jha, senior
divisional metallurgical engineer at Department of Mines
and Geology, Nepal has a billion tons and proven reserves of
210 million tons. This indicates that Nepal has an abundance
of calcium carbonate which is the key factor for the
production of acetylene. This seems to be one of the fruitful
aspects in the development of acetylene gas in our own
country, hereby reducing the maximum use of gasoline.
VIII. CONCLUSION
Rentech Symposium Compendium, Volume 1, March 2012
22