BEHAVIOR STUDY OF A DIESEL CYCLE VEHICLE WITH PURE VEGETABLE JATROPHA OIL IN QUITO CITY

Resumo

Ecuador finds an opportunity to replace fossil fuels with biofuels to reduce greenhouse gases emissions and achieve energy sovereignty since it is a country dedicated to agriculture. In high altitude cities as Quito (2800 m.a.s.l.), combustion in diesel engines is affected, emissions and particulate matter increase; consequently, opacity increases, air quality is affected and it has a negative visual impact. Jatropha oil does not contain sulfur while diesel sulfur content in the country is up to 500 ppm. Since opacity grows with the sulfur content, pure plant oil (PPO) offers an opportunity to reduce opacity; however, its calorific value and cetane number are lower than diesel, so it is necessary to study power and torque behavior. Jatropha oil needs to be heated before the fuel injection system since its viscosity is lower than diesel. This work studies the engine behavior in Quito in a vehicle regarding to power, torque and opacity using diesel and pure Jatropha oil at 25 °C and 85 °C, under normal conditions and modifying injection pressure, flow and injection time using a chassis dynamometer under a standard cycle. Fuel properties such as cetane number and viscosity are determined. In order to reduce opacity, optimum injection pressure and flow values are established when pure Jatropha oil is used at 25 °C and its behavior is studied comparing to diesel under the same conditions.