Combustion, performance and emissions characteristics of a biogas fuelled diesel engine with fish biodiesel as pilot fuel

Environmental concerns and reduction in the availability of petroleum fuels have driven interest in the search for alternative fuels for IC engines. In order to overcome the problems associated with the use of petroleum based diesel fuels, a renewable and eco-friendly biofuel can be used for partial replacement of diesel fuels. Hence in this work, feasibility of using fish oil biodiesel was investigated. The important fuel properties were evaluated. Experimental tests were carried out to evaluate the performance, emissions and combustion characteristics. A single cylinder 10 HP, constant speed, water cooled diesel engine was used for experimentation with B20 fish diesel as fuel. This study expanded to achieve diesel equivalent performance from diesel engines with maximum replacement of diesel with renewable fuels. In this context the study analysed the influence of B20 fish biodiesel as a pilot fuel in a biodiesel biogas dual fuel engine. The results of dual-fuel mode operation study are compared to those for B20 diesel operation at identical engine settings. Further for baseline comparison, the results of biodiesel and dual fuel mode of operation are compared to those of standard diesel run. Experiments were performed at various load conditions from 0 to 100% of maximum load at a constant speed of 1500 rpm. In general, B20 fish biodiesel is compatible with diesel in terms of performance and combustion characteristics. The exhaust emissions like CO and HC were significantly less, and NOx is slightly higher, than diesel fuel at all engine load conditions. Dual fuel mode of operations shows lower thermal efficiency and higher fuel consumption for other fuel mode of test run at all ranges of engine loads. Significantly lower in NOx and smoke capacity and HC, CO concentrations were considerably higher for dual fuel mode as compared to other fuels. In dual fuel mode, peak pressure and heat release rate were slightly higher compared to diesel and biodiesel mode of operation for all engine loads.