Methyl or ethyl esters of vegetable oils are the reliable alternative fuels for the petroleum diesel, because their properties are very nearer to the petroleum diesel. But the flash point and auto-ignition temperature...Methyl or ethyl esters of vegetable oils are the reliable alternative fuels for the petroleum diesel, because their properties are very nearer to the petroleum diesel. But the flash point and auto-ignition temperatures are very high for these esters. CR （compression ratio） is one of the parameter which influences the atomization and vaporization of fuel. It is also caused for improvement in the turbulence which leads to better combustion. In this work the single cylinder diesel engine was tested at different compression ratios i.e. 16.5：1, 17.5：1, 18.5：1, 19：1 with palm kernel methyl ester without modifications. On increasing compression ratio closeness of molecules of air increases and fuel is injected into that air caused for better combustion. The inbuilt oxygen of methyl or ethyl ester will participate in the combustion and causes for reduction of HC and CO. Better compression ratio for an engine with particular fuel provides satisfactory thermal efficiency and less environmental pollution. In the investigations, for palm kernel methyl ester, 18.5：1 compression ratio is preferable on single cylinder Dl-diesel engine.展开更多
Research, development and use of biofuels have emerged into focus caused by environmental protection reasons. As biodiesels （fatty acid methyl esters） have many disadvantages, the conversion of vegetable oils to bet...Research, development and use of biofuels have emerged into focus caused by environmental protection reasons. As biodiesels （fatty acid methyl esters） have many disadvantages, the conversion of vegetable oils to better quality fuels is required. One of the possible solutions is the catalytic hydrogenation of vegetable oils mixed with straight run gas oil. During quality improvement of mixtures of rapeseed oil （0, 5, 8, 12, 50 and 100%） and straight run gas oil （sulphur content： 0.95%） on NiMo, P/A12O3 catalyst at different process parameters, it was found that both the deep sulphur and nitrogen removal of gas oil and oxygen removal reactions of triglycerides （hydrogenation, decaboxylation and decarbonylation ways） and in a moderate degree the hydrogenation of aromatics took place. At favourable process parameters （350-360℃; 60 bar; LHSV： 1.5 h^-1; H2/hydrocarbon ratio： 600 Nm^3/m^3） diesel fuel fractions with sulphur and nitrogen content 〈 10 mg/kg and with significantly higher cetane numbers （〉 60-80） than the requirement of the valid standard （minimum 51; EN 590：2009＋A1：2010） were produced. During its application the concentration of sulphur and nitrogen oxides and the particulate matter is clearly lower in the exhaust gas contributing to lower emission and the conversation of the catalytic activity of the after-treatment systems.展开更多
文摘Methyl or ethyl esters of vegetable oils are the reliable alternative fuels for the petroleum diesel, because their properties are very nearer to the petroleum diesel. But the flash point and auto-ignition temperatures are very high for these esters. CR （compression ratio） is one of the parameter which influences the atomization and vaporization of fuel. It is also caused for improvement in the turbulence which leads to better combustion. In this work the single cylinder diesel engine was tested at different compression ratios i.e. 16.5：1, 17.5：1, 18.5：1, 19：1 with palm kernel methyl ester without modifications. On increasing compression ratio closeness of molecules of air increases and fuel is injected into that air caused for better combustion. The inbuilt oxygen of methyl or ethyl ester will participate in the combustion and causes for reduction of HC and CO. Better compression ratio for an engine with particular fuel provides satisfactory thermal efficiency and less environmental pollution. In the investigations, for palm kernel methyl ester, 18.5：1 compression ratio is preferable on single cylinder Dl-diesel engine.
文摘Research, development and use of biofuels have emerged into focus caused by environmental protection reasons. As biodiesels （fatty acid methyl esters） have many disadvantages, the conversion of vegetable oils to better quality fuels is required. One of the possible solutions is the catalytic hydrogenation of vegetable oils mixed with straight run gas oil. During quality improvement of mixtures of rapeseed oil （0, 5, 8, 12, 50 and 100%） and straight run gas oil （sulphur content： 0.95%） on NiMo, P/A12O3 catalyst at different process parameters, it was found that both the deep sulphur and nitrogen removal of gas oil and oxygen removal reactions of triglycerides （hydrogenation, decaboxylation and decarbonylation ways） and in a moderate degree the hydrogenation of aromatics took place. At favourable process parameters （350-360℃; 60 bar; LHSV： 1.5 h^-1; H2/hydrocarbon ratio： 600 Nm^3/m^3） diesel fuel fractions with sulphur and nitrogen content 〈 10 mg/kg and with significantly higher cetane numbers （〉 60-80） than the requirement of the valid standard （minimum 51; EN 590：2009＋A1：2010） were produced. During its application the concentration of sulphur and nitrogen oxides and the particulate matter is clearly lower in the exhaust gas contributing to lower emission and the conversation of the catalytic activity of the after-treatment systems.
