Indirect injection diesel engine operation on palm oil methyl esters and its emulsions

Abstract

Results of exhaust emissions and lube oil analysis of a diesel engine fuelled with Malaysian palm oil diesel (POD or palm oil methyl esters) and ordinary diesel (OD) emulsions containing 5 and 10 per cent of water by volume are compared with those obtained when 100 per cent POD and OD fuel were used. Very promising results have been obtained. Neither the lower cetane number of POD fuel nor its emulsification with water presented any obstacle to the operation of a diesel engine during steady state engine tests and the 20 hour endurance tests. Polymerization and carbon deposits on fuel injector nozzles were monitored. Engine performance and fuel consumption for POD and its emulsions are comparable with those of OD fuel. Accumulations of wear metal debris in crank-case oil samples were lower with POD and emulsified fuels compared with baseline OD fuel. Both OD and POD emulsions with 10 per cent water by volume show a promising tendency for wear resistance. The exhaust emissions for POD and emulsified fuels are found to be much cleaner, containing less CO, CO₂, HC, NO_x, SO_x and smoke level. Power output is slightly reduced when using POD and emulsified fuels.