Comparison and Evaluation of Engine Wear, Performance, NOx Reduction and Nano Particle Emission of Diesel, Karanja and Jatropha Oil Methyl Ester Biodiesel in a Military720 kW, heavy duty CIDI Engine Applying EGR with Turbo Charging 2020-01-0618

Global warming, stringent pollution legislations and depletion of oil reserves have opened up an opportunity to research on bio fuels. Biodiesel can be produced from edible and non-edible vegetable oils, waste bio mass and animal fats. Biodiesel is a renewable, bio gradable, sulphur free, non-toxic, oxygenated and green alternative fuel. Karanja and Jatropha oils are non- edible vegetable oils. Karanja and Jatropha oil methyl ester biodiesels are prepared by the transesterification process, using methanol. Jatropha oil methyl ester (JOME) and Karanja oil methyl ester (KOME) biodiesels have comparable performance with low gaseous emission characteristics, except a higher NOx emission, in comparison to diesel fuel. Recent emission legislations also restrict nano particle emission in addition to particulate matter, due to their adverse impact on health. In the present study, performance, combustion, emissions of carbon monoxide (CO), unburnt hydrocarbon (UHC), oxides of nitrogen (NOx) and particulate matter (PM) including nano particle emission characteristics, along with engine wear, were compared for diesel, Karanja and Jatropha biodiesel by applying 12% exhaust gas recirculating (EGR) with turbo charging, in 12 cylinders, 720 kW, 38.8 liters heavy duty compression ignition diesel injection (CIDI) military diesel engine. Both Karanja and Jatropha biodiesel fuels exhibit the ASTM standard properties within acceptable limits. Engine was subjected to 100 hours endurance run tests. Lubricating oil samples were drawn from engine after a fixed interval of 20 hours of engine run for elemental analysis. Atomic absorption spectroscopy and ferrography tests were conducted for metal wear debris concentration analysis. To test metal wear of exposed cylinder liner, scanning electron microscopy was conducted. All wear tests were conducted with a new set of engine parts for all three test fuels. Metals wear were found lowered (9-27%) for both biodiesels fuelled engine. The engine performances were evaluated in terms of power, heat release rates, and brake specific fuel consumption (BSFC). Engine performance with both Karanja and Jatropha biodiesels were slightly lower (< 2-3%) than diesel fuel. Emissions performance of Karanja and Jatropha biodiesel were better (20-74%), including 20-24% lower NOx emission, along with lower total particulate number concentration, as compared to diesel fuel with 12% EGR rate.