Source Profile Of PM_2.5 And VOCs And Source Apportionment Of Combined Air Pollution In Typical Coastal Area In Zhejiang Province

Combined air pollution is one of the most important environmental problems in China.In particular,air pollution episodes dominated by particulate matter or ozone frequently occurrences which is harmful to social economy,public health and ecological environment.Pollution source profile is the basic work of air pollution prevention and control research,which can directly reflect the characteristic of pollution source,clarify the major pollutants from emission sources,and identify the special pollution factor to indicate one unique pollution source.Simultaneously,pollution source profile is important basic data for air quality simulation and source apportionment.Air pollution simulation and source apportionment is a significant method to quantify the contribution value and rate of emission sources in simulation area.This study took the coastal area in Zhejiang province as research area.Combined with the identification of characteristic industries in research area,study on source profiles of PM_2.5 and VOCs was carried out to provide basic guarantee for accurate source apportionment.Localized PM_2.5 open source profiles of city fugitive dust,soil dust,road dust and construction dust were established.Special PM_2.5stationary source profile of coal-burning boilers dust,garbage incineration dust,metallurgy dust,together with dusts from special industries of metal manufacturing,medical waste incineration,solid waste dismantling,sludge processing,ship building and repairing and rubber manufacturing were established.Meanwhile,VOCs source profile of garbage incineration,ship building and repairing,petrochemical industry,oil storage,petrol station,printing and dyeing,aquatic products processing,sewage treatment,rubber manufacturing and coal-burning boilers were also established.For instance,ship building and repairing is typical important coastal industry.Its PM_2.5source profile showed that Fe?Zn and EC had larger mass fraction of 0.2473?0.0942and 0.0848 g·g^-1.Its VOCs source profile showed that alkane and aromatic hydrocarbon had larger mass fraction of 62.35 and 34.37 g·g^-1.Meanwhile,OFPs?Ozone Formation Potentials?profiles were also built,and industrial process dusts contributed the most on VOCs emission and OFPs of 40.90%and 44.26%.The results fill the database of source profiles in the area.Furthermore,the results provide strong support for further research on characteristics of air pollution in the Yangtze river delta.Considering the problem of colinearity among open source when executing CMB,city fugitive dust was treated as ambient receptor,enrichment factor was induced to magnify the differences between dust sources.Then,an amended CMB apportionment method was put forward as two apportionment simulation were execute on ambient dust and city fugitive dust,respectively.The contribution of soil dust,road dust,construction dust and city fugitive dust were separated and more detailed and accurate source apportionment result of PM_2.5 was acquired.The source apportionment of soil dust,road dust,construction dust and city fugitive dust were0.47%?2.24%?0.09%and 21.91%,respectively.WRF-CMAQ was applied to build 3 layer nested grids simulator for research on air pollution simulation and analysis on spatial and temporal distribution characteristic of PM_2.5 and O₃ in typical city?city ZS?.ISAM source tracking algorithm was applied to apportion the source contribution of PM_2.5?O₃?VOCs?NO₂?SO₂ and NH₃ in city ZS.Combined with the precision of CMB in primary source apportioning and the advantages of CMAQ in analyzing various pollutants,an apportionment technique was established,which not only retained the higher accuracy of CMB model on PM_2.5 primary source analysis,but also redistributed the secondary sources in CMB.Thus,more accurate and reliable source apportionment result,including primary and secondary source contribution,was obtained.Non-local source was the largest contributor of 28.30%.Shipping and on-road mobile source were in the second place of 14.62%and 11.59%,respectively.The contributions of fuel-burning boilers and industrial process were 5.27%and 7.96%,respectively.Finally,combined with the above research and other relative study from our research group,guided by regional development and emission reduction planning,this paper puts forward the strategy of combined air pollution prevention and control from the different scales of regional and key emission sources.Scenario simulation analysis method was applied to predict the pollution formation under different emission reduction scenarios,and then,to put forward the strategy of combined air pollution prevention and control from large scale.As to key emission sources in different fields,case analysis of whole process control was applied.In coastal areas,the emission control on ships should be emphasized in the field of transportation.The implementation of ultra-low emission should be accelerated and NO_X was the pollutants from coal-burning boilers that need to be controlled in priority,in the field of industrial.In the field of agricultural,the resource of crop straw could be took as one of the development directions to reduce coal consumption and air pollutant emissions in the future.Finally,it can be seen that the combined air pollution prevention strategy proposed in this study has achieved remarkable results in local air pollution prevention and control actions according to changes in environmental air quality.