Abstract:
At present, the calculation of fugitive road dust emissions mostly adopts the AP-42 emission factor method recommended by the US Environmental Protection Administration at home and abroad. It directly calculates the average annual total emission of fugitive road dust, which is difficult to meet the growing demand of refined management for the degree of dynamics is not enough. This study develops a new approach to acquire high-time-resolution traffic volume information by using traffic speed-flow model and it is the critical input data for the compilation of dynamic fugitive road dust emission inventory. Taking Tianjin as an example, this study adopts the bottom-up method and combines localized emission factors, road dust control measures of Tianjin and GIS platform to compile a high temporal and spatial resolution fugitive road dust emission inventory. It can provide methodology and guide for developing dynamic fugitive road dust emission inventory and finely reflect the time and spatial distribution characteristics of fugitive road dust emissions in Tianjin. The result show that:(1)On the time scale, affected by the morning and evening traffic peaks, the emission of urban fugitive road dust reached the maximum at 8:00-9:00 and 18:00-19:00 and the PM
2.5 emissions of per kilometer main trunk during peak time can reach 900g/h without control measures(2)On the spatial scale, the high emission areas of fugitive road dust are concentrated in the highway at night , in areas with dense urban branch roads at noon and in various urban roads at peak time. Annually, the high emission areas are concentrated in roads out of the city (3)The annual PM
2.5、PM
10、TSP emission of Tianjin are 32643、134924、7032913t. The total fugitive road dust emission of remote suburbs> four districts around the city> six city districts. Urban roads adopt effective control measures which have greatly reduced the total emission of fugitive road dust.