ON-FARM PRODUCTION OF SOYBEAN OIL AND ITS PROPERTIES AS A FUEL

This study presents the design of a system for on-farm production of soybean oil for use as a fuel in compression ignition engines. The soybean oil production system consists of a heat exchanger to heat the beans with the exhaust gas of an engine, a screw press and a system for water degumming and drying the expressed crude oil. Optimum parameters of the oil production system were found. The rheological properties of soybean oil, ester of soybean oil and blends of the above with diesel fuel and diesel fuel additives are given.;Data on soybean temperature, outlet gas temperature and thermal efficiency were obtained from a developed mathematical model of the heat exchanger. Soybean flow rate through the heat exchanger is a non-linear function of auger speed. Changes in the moisture content of the soybeans while passing through the heat exchanger are negligible.;The screw press was tested with soybeans at various temperatures to observe oil yield and energy consumption. Optimum performance occurred with soybeans heated to 49(DEGREES)C.;Chemical analyses show that crude oil from the press is similar to that of commercially degummed oil. The degumming process is not needed for the crude oil to be used as a fuel in compression ignition engines. Rheological properties of the soybean oil and soybean oil-diesel fuel mixture show that the fluids have viscosities of time independent characteristics and are Newtonian fluids. Diesel fuel additives having low viscosities can be used to lower the viscosity of soybean oil and blends with diesel fuel but the effect is insignificant.