Development Of Palm Oil Engine

With the development of global economy, the consumption of fossil fuels is increasing day by day in the modern industrial society. The scarcity of fossil fuels and the severe environmental problems have hindered the development of society, and the development and use of oil alternative fuels is imperative under the situation. As an alternative fuel that has very broad application prospect, palm oil is the vegetable oil of largest production in the world, with high oxygen content, excellent combustion characteristics and low emission.There are some problems in the application of palm oil on the engine, such as poor mobility in low temperature, bad atomization, difficult start-up, lots of carbon deposition in nozzle and combustion chamber, and so on. The application of palm oil on the engine is difficult for these problems. To solve the above problems, we can develop the heating device of palm oil and the supply system of palm oil-diesel dual fuel.According to the physical and chemical properties of palm oil, author put forward the engine retrofit scheme of starting the diesel engine with diesel oil as fuel and heating palm oil by engine exhaust and the control strategy of the supply system of palm oil-diesel dual fuel; Supply system of palm oil, heating system, control system, wire harness for palm oil engine were designed; The calibration system for ECU of palm oil engine was developed; Then, the SD1115 diesel engine was retrofited for palm oil engine and bench test was carried out. Test results showed that: palm oil in filter was heated to 83 degrees Celsius in 90s by the 24V/50W thermistor; Under 1000r/min,20N·m condition, palm oil in the heater in the 320s could be heated to 60 degrees Celsius by waste heat of the engine, the highest temperature of palm oil up to 75 degrees Celsius; Under calibration condition, palm oil in the heater in the 200s could be heated to 60 degrees Celsius by waste heat of the engine, the highest temperature of palm oil up to 110 degrees Celsius. Experimental results verified the effectiveness of palm oil heater and the control system of the palm oil engine and the feasibility of the transformation scheme of the palm oil engine.Tests carried out on the palm oil engine with palm oil of 80 degrees Celsius were compared with the diesel fuel of 30 degrees Celsius without adjustment of oil pump and oil nozzle. Results of bench test showed:The maximum torque with burning palm oil is up to 98.5% for diesel and the maximum power is up to 97.3%. Combustion starting point of burning palm oil is ahead of that of diesel and the maximum explosion pressure and the pressure rise rate lower. Combustion noise, exhaust-gas temperature, equivalent fuel consumption are lower and the circulatory fluctuation is less at 1000r/min,30N·m. But, the effective thermal efficiency is higher. Under load characteristics of 1600r/min and 2200r/min, HC emission at 1600r/min was higher and at 2200r/min had little difference. NOx emission at high speed and large load was slightly higher and under other conditions were lower. CO emission and smoke intensity were lower and decreased 50% and 40% maximumly respectively at high speed and large load. After 50 hours of continuous operation under the calibration condition, the result showed that the carbon deposition in the nozzle and the bottom of the combustion chamber was more obvious when the palm oil was burning; The above results showed that the transformation of the palm oil engine was successful, and it could achieve the application requirements of the enterprise.