杭州市区机动车危险气态污染物排放的模型计算

通过对杭州市区机动车保有量及其构成、车辆登记分布和累积行驶里程的调查分析，获得了杭州市区机动车的基本运营特征参数.采用修正的MOBILE6.2 模型计算了杭州市区2003年机动车排放的危险气态污染物（苯、1,3-丁二烯、甲醛、乙醛和丙烯醛）的排放因子.并在此基础上计算了杭州市区机动车危险气态污染物的排放清单和分车型的排放分担率.结果表明，杭州市区机动车危险气态污染物的综合排放因子很高，汽油车、摩托车、重型柴油车的
排放因子分别是美国同期水平的1.3～6.9、1.7～4.4和3倍，2003年杭州市区机动车危险气态污染物苯、1,3-丁二烯、甲醛、乙醛和丙烯醛总量分别为810.0、116.7、412.2、123.8和18.0 t.研究还表明，车速对此类污染物的排放影响很大，当平均车速大于30 km/h时，排放因子明显减小.

Estimation of motor vehicle air toxic emissions in urban area of Hangzhou, China

Vehicle activity data in Hangzhou were investigated,including vehicle population distribution,vehicle registration distribution and mileage accumulation rates(MAR).The MOBILE6.2 model developed by Environmental Protection Agency of the United States(USEPA) was modified and used to calculate the emission factors of the air toxics of interest,including benzene,1,3-butadiene,formaldehyde,acetaldehyde and acrolein.The total air toxics emissions per year from motor vehicles were estimated and different vehicles' contributions to the total vehicular emissions were calculated.Results showed that the emission factors of air toxics from gasoline vehicles,motor cycles and heavy-duty diesel vehicles are quite large,and are 1.3~6.9,1.7~4.4 and 3 times respectively those of the American average emission level during the same period.The total emissions of benzene,1,3-butadiene,formaldehyde,acetaldehyde and acrolein from vehicles were 810.0,116.7,412.2 and 18.0 t respectively in Hangzhou in 2003.Study on the relationship between emission factors and vehicle speeds demonstrated that the emission factors of air toxics are low when the average speed is above 30 km/h.