33年来中国铁路运输行业的大气污染物排放

铁路是中国重要的交通运输方式,但中国至今尚无铁路运输行业大气污染物排放的报道.根据中国铁路部门逐年统计数据,采用基于燃料消耗量的排放因子法,估算了1975～2007年中国铁路机车大气污染物排放量,并分析了大气污染物排放强度及其变化.结果表明,33年来中国铁路机车烟尘、SO2、CO和CnHm排放量逐年降低,分别由1975...

Air Pollutants Emissions of Locomotives in China Railways in Recent 33 Years

Although railway has played a great role in transportation in china,there has been no any study on air pollutants emissions of locomotives until now. Based on the annual statistical data collected by the Chinese Railway Statistic Center,using the emission factor method derived from fuel consumption,the air pollutants emissions of locomotives during 1975-2007 were calculated,and their emission intensities and dynamic characteristics were analyzed. The results show that the emissions of soot,SO₂,CO and C_nH_m from steam and diesel locomotives in china decreased from 3510.6 thousand,399.7 thousand,846.0 thousand and 845.3 thousand ton in 1975 to 78.7 thousand,11.4 thousand,36.7 thousand and 26.4 thousand ton in 2007,indicating a decrease of 107.0 thousand,12.1 thousand,25.3 thousand and 25.6 thousand ton per year,respectively. However,the emissions of NO_xshowed an increase trend from 34.8 thousand ton in 1975 to 98.3 thousand ton in 2007 with an increase rate of 2.0 thousand ton per year. The emission intensities of soot,SO₂,CO and C_nH_m decreased significantly from 686.2,78.1,165.4 and 165.2 g/(hundred converted ton-km) in 1975 to 5.4,0.8,2.5 and 1.8 g/(hundred converted ton-km) in 2007,respectively. The emission intensity of NO_xfluctuated in the range of 5.0-8.0 g/(hundred converted ton-km). Air pollutants emissions of locomotives accounted for very little of the total emissions in China,and the emission intensities decreased persistently. It shows that railway transportation is a perfect way of saving energy and reducing emission in the sector of transportation.