论文部分内容阅读
1机动车的排放污染物随着机动车数量的逐年增加,机动车尾气排放对大气环境的影响也愈来愈严重,机动车尾气污染已经成为影响城市空气质量的重要因素。我国也先后出台了多个相关标准,对机动车尾气排放的检测方法和限值都做出了明确而具体的规定和要求。机动车的排放污染物主要有3种形式:一是尾气排放污染物,即由排气管中排出的废气,主要有一氧化碳(CO)、碳氢化合物(HC)、氮氧化合物(NOx)、铅化物、硫化物等;二是曲轴箱排放污染物,是由活塞环与气缸的间隙漏入曲轴
1 Motor vehicle emission pollutants As the number of motor vehicles increases year by year, the impact of motor vehicle exhaust emissions on the atmospheric environment is more and more serious. Motor vehicle exhaust pollution has become an important factor affecting the urban air quality. China has also promulgated a number of relevant standards, the vehicle exhaust emission detection methods and limits have made clear and specific provisions and requirements. There are three main types of pollutants emitted by motor vehicles: one is pollutants discharged from the exhaust gas, that is, the exhaust gas discharged from the exhaust pipe is mainly carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NOx) Lead compounds, sulfide, etc .; the second is the crankcase emissions of pollutants, the piston ring and cylinder through the gap leakage into the crankshaft