A Highly Resolved Temporal And Spatial Motor Vehicles Emission Inventory And Emission Reduction Strategy In The Harbin-Changchun Megalopolis

With the rapid development of China’s economy and the accelerating urbanization process,the number of motor vehicles as the most important means of transportation in the city has increased dramatically in decade years.By the end of 2016,the number of motor vehicles in the Harbin-Changchun megalopolis has exceeded 7,140,200.The pollution characteristics of the atmospheric environment in the Harbin-Changchun megalopolis have been transformed from soot-type pollution to combined pollution of soot and motor vehicle exhaust.As the number of motor vehicles increases,the vehicle pollution has a higher contribution to air pollution.Therefore,to a vehicle emission inventory for the Harbin-Changchun megalopolis is essential to provide a scientific basis for formulating effective pollution control strategies by exploring the characteristics of motor vehicle pollutant emissions.Firstly,considering the vehicle composition,road driving characteristics and meteorological conditions of motor vehicles,the vehicle emission factors in the HarbinChangchun megalopolis is established by combining with the“Technical Guidelines" and the IVE model method.The results show that the emissions of CO,HC(includes gasoline vehicle evaporative emissions),NOx,PM2.5,PM10,VOC and NH3 were 625,660 tons,130,400 tons,215,150 tons,11,200 tons,12,200 tons,80,500 tons and 5,200 tons in 2016,respectively.Secondly,the contribution rate of motor vehicles to total pollutant emissions in different seasons,models,fuels,emission standards and road types is analyzed.The results show that(1)the emissions of motor vehicles during the heating season are significantly higher than those in the non-heating season;(2)the small and medium passenger cars and ordinary motorcycles of gasoline vehicles are the main sources of CO and HC emissions,accounting for 86.43%and 82.31%,respectively;(3)the heavy-duty trucks in diesel vehicles are major sources of NOx and PM emissions,accounting for 86.48%and 89.68%,respectively;(4)the contribution rate of motor vehicles to pollutants of emission standard Ⅰ and Ⅱ is higher than the proportion of possession,and the cumulative effect can reach up to 48%;(5)the highway has a high contribution to NOx and PM,while the contribution rate of main roads,secondary roads and branch roads to CO and HC is as high as 80%.Then,the temporal-spatial characteristics of motor vehicle pollutants are analyzed by establishing a 3 km×3 km gridded emission inventory with ArcGIS software.The results show that pullutions are concentrated in Changchun,Harbin,Jilin and Daqing with high road network and heavliy traffic.In addition,affected by the life time of the citizens,the daily emissions of road vehicles have obvious double peaks during the morning peak and the evening peak.Finally,combined with the pollution emission characteristics and actual conditions of motor vehicles,a variety of emission reduction schemes were set up.The research shows that the accelerated elimination of old vehicles has the most obvious effect on vehicle emission reduction.The reduction rates of CO,HC,NOx,PM2.5 and PM10 are 19.83%,19.55%,8.62%,18.27%and 18.76%,respectively.In addition,it is necessary to further restrict new energy vehicles,develop public transportation,improve fuel quality and implement vehicle emission standards in advance in order to control motor vehicle emissions in the region.