Emissions Inventory Of Anthropogenic Vocs In The Main City And The Affected Area Of Chongqing

Chongqing is a municipality with mountaineous terrain in China.It is also an old industrial city.Chongqing is one of the most polluted cities in China.With the city’s development and the rise of industrial enterprises,volatile organic compounds(VOCs)play an important role in environmental pollution.The volatile organic compound is a precursor that causes ozone pollution and PM2.5 formation,and itself can also adversely affect human health.Emission inventory of anthropogenic VOCs can be a guide for government to make emission reduction policies,and is an important input parameter for air quality models.The establishment of VOCs emission inventory in Chongqing is favaorable to the evaluation of air quality and can provide basic information for pollution control.Firstly,emission sources were classified into four categories,based on the emission source classification system.Then,basic emission data was obtained from surveys,statistical yearbook,field investigation,related literatures and statistical calculation.After that,data were integrated and screened to get the level of activity and emission factors of each source.Finally,using the most popular emission factor method to establish the emission inventory of anthropogenic VOCs of 2015 in Chongqing urban area and influence area.According to above method,the emission inventory of anthropogenic VOCs in urban area and influence area of Chongqing was established,and the emission characteristics of VOCs were analyzed.The inventory was verified by the emission ratio method,and allocated to grid cells through ArcGIS.Results showed that Total emission load of anthropogenic VOCs in Chongqing urban area and influence area was 223,000 tons.The emission load of biomass combustion source,fossil fuel combustion source,process source,solvent using source and automobile source was 0.2 million tons,0.6million tons,68,000 tons,84,000 tons,and 53,000 tons,respectively.The corresponding contribution rate was 1.0%,2.5%,30.6%,37.8%,and 28.1%.Yubei,Jiulongpo and Bishan were districts with largest emissions,which in total accounted for 42.9% of total emission.Dadukou was the district with least emission,which was below 10,000 tons.Equipment manufacturing industry contributed most to VOCs emissions,with the emission load of 49,000 tons,accounting for 46.7% of total industrial emission.Rubber and plastic industry and construction materials industry took the second and third place,and the emission load was 22000 tons,and 10000 tons,accounting for 21.2% and 9.7%of total industrial emission.Furniture manufacturing industry contributed least,and accounted for only 1.0% of total industrial emission.Automobile source was major VOCs emission source inYuzhong District,while process source and solvent using source were main sources in the other areas.The uncertainty of VOCs emission load in urban area and influence area in Chongqing was assessed using Monte Carlo model and results was(-37.3%,+ 70.5%)under 95% confidence interval.VOCs emission inventory was validated using the emission ratio method,which calculated that anthropogenic VOCs emission in Chongqing was in the range of 294,000 and 672,000 tons.With ArcGIS,VOCs emission inventory was allocated to grid cells with the resolution of 1 km × 1 km.From the spatial distribution point of view,biomass combustion source was mainly distributed in Yuzhong District,Dadukou District,and the junction between Nan’an Distric and Banan District and,as well as two influence areas.Fossil fuel combustion source,process source,and solvent using source distributed in various areas.The non-point source concentrated in Yuzhong District and the rim.Automobile VOCs emission concentrated in Yuzhong District,main roads,inner ring,outer ring and city expressway.