A Study on Practical Use of Cellulosic Liquefaction Fuel in Diesel Fuel

Abstract

The cellulosic liquefaction fuel (CLF) was made from woods by the direct liquefaction process. Coconuts-oil Methyl Ester (CME) of 5 wt.% was used to mix CLF and diesel fuel, because CLF was not completely mixed with diesel fuel. To clarify a desirable CLF fraction for the diesel engine, CLF was divided into two fractions by the distillation: 200 to 250 °C (CLF1) and 250 to 300 °C (CLF2). The weight mixing ratio of CLF in blended fuel was varied until 20 wt.% to analyze ignition characteristics and performance of diesel fuel-CLF-CME blends. The brake thermal efficiency of both CLF mixed fuel was almost equal to diesel fuel, however high NOx was emitted at a high load. This is because the combustion gas temperature was increased by a rapid combustion pressure rise. The smoke concentration of CLF mixed fuel was lower than that of diesel fuel. When CLF1 or CLF2 is mixed with diesel fuel by using 5 wt% of CME and the weight mixing ratio of CLF is up to 20 wt%, CLF mixed fuels have almost no influence on engine performance. For both CLF1 and CLF2 mixed fuel, it is possible to operate diesel engine without any remarkable deterioration of engine performance. When 5 wt.% CLF was mixed to diesel fuel with CME, diesel engine could be continuously operating for 8 hours without any deterioration. The ignition timing of CLF1 mixed fuel was slightly earlier than that of CLF2 at any mixing ratios, therefore CLF1 was suitable for diesel engine.