Результаты производствнных исследований использования моторного биотоплива

Abstract

Operating at optimum load with the working speed of 2,5 to 2,6 m/s and the traction power of 26,4 to 27,0 kN, the comparative fuel rate on RME increased by 8 to10  compared with mineral diesel. The environmental effect of biodesel and its mixes with mineral diesel was established. The trials carried under operating conditions show that when biodiesel and its mixes with mineral diesel were used, NOx amount in oxides increased with the higher amount of RME in the fuel mix. When the tractor operated on pure RME, NOx emissions increased by 6 to 9 % against mineral diesel. Having summed up the obtained results it can be stated that the amount of NOx in oxides is proportional to the amount of RME in them. The higher is RME amount in a mix, the more NOx is there. Nevertheless, in all tested cases this amount did not exceed the allowed rate, which was 600 mg/m3. The measurements of CO amount in oxides allow making a conclusion that replacement of mineral diesel with pure RME will result in reducing CO amount by 5,5 to 8,5 % for both 18 kW and 58 kW tractors depending on the tractor load. The minimum relative CO amount in engine oxides was obtained, when the engine was loaded by 70-80 %. Operation on partial (30 to 50 %) or full (90 to 100 %) load increased CO amount by 50 to 80 % compared with that on 73 to 80 % load. The study of dependence of exhaust smoking on the load showed that replacement of mineral diesel with pure RME reduced exhaust smoking by 40 to 70 %. When the tractor load was 73 to 80 %, exhaust smoking was the lowest. At the Lithuanian Institute of Agricultural Engineering experiments were carried out on pure rape-seed methylester (RME) and its mix with mineral diesel (M) application in tractor units of different power. The dynamics of comparative fuel rates was determined for 18 kW tractor unit at maximum tractor tractive force Pmax operating under the same conditions with mineral diesel, RME and their mix. The trials were carried out driving at four gears, with 1,2 to 2,7 m/s working speed. The lowest comparative traction fuel rate was achieved at maximum traction power of tractor Pmax 11,1-12,2 kN and working speed vd 1,8-2,1 m/s, correspondingly: M – 210 g/kWh; M+30  RME - 213 g/kWh; M+50  RME- 229 g/kWh; 100  RME- 248 g/kWh. Obviously, when tractor unit operated at optimum load on pure RME, fuel rate increased by 12  compared with mineral diesel. Operating on mixes containing 50  and 30  of RME the fuel rate increased by 5,8  and 3,9 , correspondingly. Comparative fuel rate was also determined for 58 kW power tractor unit at maximum traction power of tractor Pmax and nominal engine acceleration mode under the same conditions as mineral diesel, RME and their three mixes. The trial was performed at 1,5 to 2,7 m/s working speed of the tractor unit. The minimum comparative fuel rate of the tractor unit was registered at the maximum traction power of tractor Pmax 31,5-32,4 kN and working speed vd = 2,3-3,4 m/s, accordingly: M – 451 g/kWh; M+30  RME - 469 g/kWh; M+50  RME - 478 g/kWh; 100  RME - 505 g/kWh. Thus, when 58 kW tractor operated at optimum load on 100  RME, the comparative fuel rate increased by 8,9  compared with mineral diesel. Operating on mixes containing 50  and 30  of RME the fuel consumption increased by 6  and 4 , correspondingly. Similar dependencies were obtained in experiments on comparative fuel rate of the tractor unit with 151 kW tractor.