This document discusses biogas as an alternative fuel source and its use in dual fuel diesel engines. It introduces biogas as a renewable fuel produced from organic waste that can help address issues with fossil fuel depletion and emissions. It then describes how diesel engines can be modified to run primarily on biogas, with a small amount of diesel to aid combustion. Performance metrics like torque, fuel consumption, efficiency and emissions are evaluated at different biogas percentages and compression ratios. Results show dual fuel engines can reduce emissions compared to diesel while maintaining power levels with only minor engine modifications.

1. Biogas Diesel Engine
Presentation by :
FAZEEL MOHAMMED N M
MECHANICAL ENGINEERING
TKMCE ,KOLLAM

2. INTRODUCTION
We have limited resources available on earth.
 Our demands are continuously increasing day by day.
Fossil fuels are fast depleting than we imagine .
Someday the non-renewable resources get exhausted. Can
you imagine a day without that?
 Fossil fuels raises serious environmental concerns.
Burning of fossil fuels produces 21.3 Gigatonnes of CO2,
causing serious environmental problem.

3. WHAT WE CAN DO ?
RECYCLE - compositing waste materials into new products to prevent waste
of potentially useful materials.
Switch over to alternate energy sources
We save our money
when we save energy
We reduce pollution
when we save energy

4. WHY BIOGAS ?
Biogas is an alternative and renewable energy, produced by the
anaerobic decomposition of organic matter .
Cheaper Technology and Recycle of organic matter is possible.
Biogas is a GREEN FUEL , can power Earth for days to come.
Biogas can reduce CO2 emission as compared to fossil
fuels.
 Biogas can be produced at house levels too.

5. Dual Fuel Engine
Modifications are made in the conventional Diesel Engine to
convert to 80-90% biogas engine .
 A Gas Carburettor is connected to inlet manifold , where
biogas and air is mixed in the ratio.
 The supply of diesel is controlled by a governor ,controlled by
ECU of the engine.
 Diesel is supplied to engine cylinder (10-20%) to aid in
combustion of biogas

6. Modifications in Diesel engine

7. Dual Fuel Engine
 Dual Fuel Engine is started on diesel ,the main valve is
gradually opened .
 As the Biogas enters ,the engine speed increases.
 The governor automatically reduces the intake of diesel oil,
thereby reducing speed of engine .
 Heating of intake Biogas-air mixture enhances combustion.
 Increasing the Compression ratio increases efficiency .

8. Performance of Dual Fuel Engine
The Performance Is Investigated on the following grounds :
 Engine Torque / Load torque
Brake Specific Fuel Consumption
Brake thermal Efficiency
Emission Characteristics

9. Engine Torque
 For compression ratio of 14 , as Biodiesel percent increases the
Torque decreases .
 As compression Ratio increases from 14 to 16 ,Engine torque
increases .
 For the same blend , increasing the compression ratio had
more benefit with biodiesel than with high pure diesel .

10. Torque vs. Speed

11. Brake Specific Fuel Consumption
 For the same Compression Ratio , there is higher specific fuel
consumption than diesel fuel at same rpm .
 For same blend , as Compression Ratio increases specific fuel
consumption decreases .
 Biodiesel gives a better decrease in BSFC than diesel as the
compression ratio increase .
 It may be due to lower volatility and higher cetane number of
biodiesel compared to diesel fuel.

12. BSFC vs. Compression Ratio

13. Brake Thermal Efficiency
 Brake thermal efficiency of the engine, in general, reduced with
the increasing concentration of biodiesel in the blends.
 Increasing the Compression Ratio improved the efficiency of
the engine .

14. Brake Thermal Efficiency vs. Compression Ratio

15. CO EMISSION
 Effect of Blend : Co emission decreased with increasing engine
speeds for all blends till 1700 rpm, then increase with
increasing the speed .
 Effect of Compression Ratio : CO emission reduced when
compression ratio was increased from 14 to 18 .

16. CO EMISSION vs. COMPRESSION RATIO

17. NOX EMISSION
 Effect of blend : All blends of Biogas produced higher NOx than
pure diesel for all engine speeds at all compression ratios .
 Effect of compression ratio : NOx emission increases as
compression ratio increases from 14 to 18.

18. NOX EMISSION vs. COMPRESSION RATIO

19. CONCLUSION
 CO Emission produce less exhaust emissions than
conventional diesel engines without any substantial
increase in operating and capital cost.
 Increasing the compression ratio improved the
performance and cylinder pressure of the engine.
 The mole fraction of H2O increases with bio-gas
substitution , this decreased the peak combustion
temperatures.

20. REFERENCES
• Mohammed EL_Kassaby, Medhat A. Nemit_allah, (2012) Studying the effect of
compression ratio on an engine fueled with waste oil produced biodiesel/diesel fuel,
Alexandria Engineering Journal
• Shaik Magbul Hussain, Dr.B. Sudheer prem kumar, Dr.K .Vijaya Kumar Reddy
,(2013) Biogas Diesel Dual Fuel Engine Exhaust Gas Emission, International Journal
Of Advanced Research In Engineering And Technology.
• N.H.S.Ray, M.K.Mohanty, R.C.Mohanty, (2013) Biogas as Alternate Fuel in Diesel
Engines: A Literature Review, IOSR Journal of Mechanical and Civil Engineering
• Bhaskor J. Bora , Ujjwal K. Saha , Soumya Chatterjee, Vijay Veer(2014) Effect of
compression ratio on performance, combustion and emission characteristics of a
dual fuel diesel engine run on raw biogas, Energy Conversion And Management .
• M. Mohamed Ibrahim, , J. Varuna Narasimhan, A. Ramesh (July 2015) ,
Comparison of the predominantly premixed charge compression ignition and the dual
fuel modes of operation with biogas and diesel as fuels ,Energy.