Preparation Of Emulsions From Biomass Pyrolysis Liquid And Diesel And Their Use In Engine

Due to the shortage of fossil fuel resources and the environmental pollution associated with the excess use of the fossil fuels, new and renewable energy sources have been developed rapidly in many countries. Substitute fuels have attracted more and more attention worldwide.This study reviewed the world's energy development conditions and the development trend of renewable energy resources, introduced the development of bio-energy and the utilization of bio-oil, and then proposed the scope and significance of the study on bio-oil/diesel oil emulsified fuels.Pyrolysis derived bio-oil was emulsified by diesel oil with complex of nonionic surfactants. The density, calorific value and pH value of the emulsified fuel were measured. Taking the stability of the emulsion as the evaluating index, the effect of surfactant type and content, bio-oil content in the emulsion were investigated. Experimental results show that the optimal emulsion could be obtained when the content of nonionic surfactants combined by Span 80 and Tween 80 is 2%, bio-oil content is 20%, and the emulsification time is 30 min in a water bath of 40℃. The density of the emulsion increases and the pH and calorific value decrease with the increase of the bio-oil content.The performance of bio-oil/diesel oil emulsified fuels with four different bio-oil/diesel oil ratios were tested on a SD1110 diesel engine, the engine load characteristics and exhaust emission characteristics curves of diesel engine were determined, and then, the fuel economy and exhaust emission characteristics of the engine fueled with the emulsified fuel were analyzed in comparison with that of the pure No.0 diesel oil. The experimental results show that, when the engine is fueled with the emulsified fuel at bio-oil concentration of 20%, the specific fuel consumption is the lowest. Moreover, the NO and smoke emissions of the emulsified fuels are lower than that of the pure No.0 diesel oil.Finally, problems for applying the bio-oil/diesel emulsified fuel to the diesel engine are pointed out, measures for solving these problems are proposed and suggestions for further study are also given.