A Study of Utilization of Coconut Oil for Diesel Fuel

为了将椰子油用作柴油，对椰子油甲酯的制备工艺、燃料性质和柴油燃烧特性进行了研究。CME由烷基催化酯交换反应和水洗反应制得。实验分析表明，满足欧盟生物柴油标准的椰子油酯交换反应条件为：醇量比为1.8~2.0，KOH用量为椰子油质量的1%，反应温度为60℃，反应时间为1 h。与RME和PME相比，CME具有较低的运动粘度和较高的挥发性。在一台单缸直喷式柴油机上研究了共燃式柴油的燃烧特性和排放特性，并与℃、RME和JIS2号汽油机油进行了对比。…的喷油正时和点火延时更多的CME与JIS 2号柴油的CME基本相同。CME的热效率与其他试验燃料的热效率几乎相同。由于CME的含氧量较高，其排放(HC、CO、NOx和烟度)比其他试验燃料低。特别是在100%负荷条件下，与JIS 2号汽油相比，CME的烟度排放降低了约50%。从实用角度出发，进行了20%CME与80%JIS 2号柴油(CME-B20)的调合试验。CME-B20的凝点为-12.5℃，与JIS2号柴油的凝点相同。研究了燃用CME、CME-B20、RME和JIS 2号燃料油的柴油机连续运行50h后的排放和燃烧室积碳情况。运行50小时后，CME的燃烧室积炭比JIS 2号汽油高60%左右。运行50小时后，CME-B20的积碳量略低于CME。运行50小时后，发动机润滑油的酸值与汽油的酸值基本相同。实验结果表明，与PME和RME相比，CME是一种较好的柴油代用燃料。较少

In order to use coconut oil as a diesel fuel, the manufacturing process, the fuel properties and the diesel combustion characteristics of coconut oil' methyl ester (CME)are investigated. CME is made by alkyl catalyst transesterification with water washing. From the experimental analysis, it is shown that the reaction conditions of transesterification from coconut oil to CME to satisfy the EU standard of bio-diesel are that the ratio of methanol amount to its stoichiometric value is 1.8 to 2.0, the KOH amount is 1% mass to coconut oil, the reaction temperature is 60℃, and the reaction time is one hour. CME has low kinematic viscosity and high volatility compared to RME and PME. The pour point of CME is -5.0℃ and it is not reduced by adding the pour point depressant.The combustion characteristics and exhaust emissions of CME are investigated using a single cylinder direct injection diesel engine, and are compared to PME, RME and JIS No.2 gas oil. The injection timing and ignition delay o … More f CME are almost the same as those of JIS No.2 gas oil. The thermal efficiency of CME is almost the same as the other test fuels. The exhaust emissions (HC, CO, NOx and Smoke) of CME are low compared to the other test fuels due to the higher oxygen content of CME. Especially, at 100% load condition, about 50% reduction in smoke emission is found in CME compare to that of JIS No.2 gas oil. From the practical viewpoint, a blend of 20% CME with 80% JIS No.2 gas oil (CME-B20) is tested. The pour point of CME-B20 is -12.5℃, is same as that of JIS No.2 gas oil. The CO, HC and Smoke emissions of CME-B20 are lower than those of JIS No.2 gas oil.The exhaust emissions and carbon deposit in combustion chamber of diesel engine continuously operated for 50 hours by fuelling CME, CME-B20, RME and JIS No.2 gas oil are investigated. The carbon deposit in combustion chamber after 50 hour run for CME is about 60% higher than that for JIS No.2 gas oil. The carbon deposit of CME-B20 after 50 hour run is slightly lower than that of CME. The acid value of lubricant engine oil after 50 hour run for CME is almost the same as that for the gas oil. It is considered that the carbon deposit of CME must be investigated in detail with the carbon deposit formation mechanism in combustion chamber.From the experimental results, it is concluded that CME is a good alternative fuel as diesel fuel compared PME and RME. Less