混合燃料中含氧量对柴油机有害物质排放量的影响

Influence of fuel oxygen content on engine exhaust emissions

通过柴油机试验,研究了混合燃料中含氧量对柴油机有害物质排放量的影响。试验结果显示,在混合燃料中含氧量低于10.4%(质量分数,下同)时,CO和HC排放量随含氧量增加而减少;但随着混合燃料中乙醇所占比例增加,当混合燃料中含氧量达25.3%时,CO和HC排放量均增加到含氧量为10.4%时的2.5倍左右;当混合燃料中含氧量低于10.4%时,NOX排放量随其增加而少量增加,但当混合燃料中含氧量达25.3%时,NOX排放量较燃用柴油时减少50%以上;碳烟排放量则随着混合燃料中含氧量增加而不断减少。

Series of diesel-rice bran oil biodiesel （RBD）-ethanol blend fuel were prepared to detect the influence of oxygen content on diesel engine exhaust emissions. Blend fuel could be distinguished as high oxygen content level （oxygen content： 10.4%-25.3%） and low oxygen content level （oxygen content〈10.4%）. CO and HC emissions decreased with the increasing of oxygen content under low oxygen content level. The emissions trend was contrary to that under high oxygen content level. The CO and HC emissions （oxygen content： 25.3%）were 1.5 and 2.5 times as much as that when oxygen content was 10.4%. At low oxygen content, increasing of fuel oxygen content resulted in higher NOx emissions, but the NOx emissions decreased when the blend fuel to higher level oxygen content. The NOx emissions reduced 60% when the oxygen content increased to 25.3%. The soot emissions continued decreased with increasing of oxygen content.