Emission Inventory and Characteristics of Anthropogenic Air Pollutant Sources in the Sichuan Province

Abstract

Based on anthropogenic source activity data and emission factors for the Sichuan Province, the 1 km×1 km-gridded atmospheric air pollutant emission inventory of 2015 was developed in combination with GIS technology and the combined "bottom-up" and "top-down" construction method. The results show that the total emission of SO2, NOx, CO, PM10, PM2.5, BC, OC, VOCs, and NH3 in Chengdu is 444.9×103, 820.0×103, 3773.1×103, 1371.6×103, 537.5×103, 28.7×103, 53.1×103, 923.6×103, and 988.0×103 t, respectively. Power plants and other industrial combustion boilers contribute more than 95% of the SO2 emissions. Mobile, fossil fuel combustion, and industrial process sources contribute 54%, 23%, and 20% of the NOx emissions, respectively. The industrial process of steel production and building materials manufacturing contribute 20% PM10 of the emissions and take up 34% PM2.5 of the emissions. Fugitive dust and road fugitive dust contributes 60% PM10 and 35% PM2.5 of the emissions, respectively. Biomass combustion contributes 33% BC and 51% OC of the emissions, respectively. The solvent use of mechanical processing, building decoration, electronic equipment manufacturing, and printing and furniture industry contribute 46% of the VOCs of the emissions. The NH3 emissions mainly orginate from the sources of livestock feeding and nitrogen fertilizers, accounting for 70% and 25% of the NH3 emissions, respectively. The spatial distribution of the emissions shows that high emissions are mainly distributed in the most densely populated, agricultural, and industrial more developed areas in Panzhihua and the Sichuan Basin. The urban agglomerations of the Chengdu Plain, represented by Chengdu, Deyang, and Mianyang, are the areas with emission concentration in the Sichuan Basin. The emissions inventory in this study has uncertainties. More fundamental studies on activity data should be conducted and the emission factors of typical emission sources should be further localized to improve the emission inventory and prevention and control of complex air pollution in the Sichuan Province and provide scientific support.