Potential of a Dual Fuel DI Diesel Engine Fuelled with Jatropha Curcas L. Oil and Producing Gas Derived from Biomass

High energy demand and environmental pollution leads to seeking of new, renewable and clean energy as biofuel and biomass. These fuels are abundant in tropical areas and agricultural-economic-based countries. Among various crops which are used for biofuel, Jatropha Curcas L. Oil (JO) is more beneficial and attractive as it is non-edible which is not competitive with food demand. In agricultural sector, the biomass waste especially from rice production such as rice husk is a tremendous resource in Cambodia. The combination of the use of biomass from rice husk (RH) and Jatropha Cake (JC) from the JO production in the gasification can produce more energy for the electricity production especially in the remote and rural area. In previous research, some researchers have been investigated on the use of JO in blending ratio, heated-neat condition and dual fuel combustion of diesel and bio-digested biogas. The use of crude-neat JO and producing gas from the gasification has never conducting yet. In this study, mixed combustion of dual fuel of neat JO and producing biogas (BG) in single cylinder, direct injection compression ignition engine was conducted at fixed injection timing θ_j = 17 °bTDC, with two mixing ratios of producing gas r_{pg = 25 and 50% in energy base as JOHBG25 and JOHBG50 at low, medium and high loads. The producing gas which composes of hydrogen, carbon mono-oxide, methane, carbon dioxide, nitrogen and oxygen from the gasification was replaced by the simulated gas and was fed from gas cylinder. In previous experiments, pressure histories were recorded and engine outputs and combustion characteristics such as thermal efficiency, specific energy consumption, rate of heat release, maximum pressure-rise rate, maximum heat-release rate were recorded and analyzed, and exhaust gas emissions were measured. From the results, at low load, JOHBG25 is better for its thermal efficiency. Both dual fuels JOHBG25 and 50 produced lower maximum pressure-rise rate, compared to JO and diesel with similar brake specific energy consumption (BSEC). In all loads, JOHBG25 and JOHBG50 produce higher CO and THC but less NOx, opacity and smoke compared to JO and diesel.}