Volatile Organic Compounds(VOCs)Source Profiles For Industrial Sources And It's Application In PMF Source Apportionment

Goal for solve the uncertainties for volatile organic compounds(VOCs)positive matrix factorization(PMF)source apportionment caused by the photochemical aging of the source and the factor identification using literature source tracers rather than emission characteristics of local emission sources.In this paper,VOCs as the important precursors of ozone and secondary organic aerosols,were selected to study the source characteristics of different industry and their application in urban source apportionment.In order to establish a more effective solution of positive definite matrix factorization(PMF)source apportionment method,the technical route of "local source measurement-sources clustering-principal component factor extraction – primary PMF source apportionment-determination of fresh primary source-secondary PMF source apportionment" was proposed in this study.Taking Zhuhai as an example,we tested and analyzed the representative industries and ambient air by TO-14 and TO-15 methods recommended by the US environmental protection agency.Four categories were determined for the local industrial sources according to the results of cluster analysis,and the marker of VOC species for industrial sources were extracted by principal component analysis.The different degrees of photochemical processing of factors were used for primary PMF source apportionment,and local fresh primary sources were determined for secondary source apportionment.Combining the VOC marker of local sources and the results of secondary PMF,the contributions of local emission sources of VOCs were discussed.The results and conclusions are as follows:(1)Four VOC source categories were determined according to clustering analysis of source profiles similarity.The first one covered 6 industries and contained non-ferrous metal smelting and rolling processing industry,textile industry,pharmaceutical manufacturing industry,electronic manufacturing industry,furniture manufacturing industry,metal product industry;The second one included chemical raw materials and products manufacturing industry,rubber and plastic products industry,electrical machinery and equipment manufacturing industry;The third one included printing and recording media reproduction industry and automobile manufacturing industry.The fourth one is crude oil processing and petroleum products manufacturing industry.(2)Oxygenated volatile organic compounds(OVOCs)is the principal component for the first VOC source categories,specifically,acetone is the most important species,trichloroethylene and cyclohexane are the second principal component,acetonitrile and dichloromethane are the third principal component.Benzene series is the principal component for the second categories,with benzene and toluene as the main components,and OVOCs,such as 2-butanone and acetone as the second principal component.The first principal component of the third category is cis-1,2-dichloroethylene,and the second principal component are 3-methylhexane and n-pentane.The fourth-class industry takes ethane and n-hexane as the primary components.C2-C4 small molecule alkenes and C6-C9 aromatic hydrocarbons are the first major component for local motor vehicle source,and macromolecular alkanes and benzene series are the second major component.(3)There are four factors for the first PMF source apportionment,including fresh primary,aged primary,secondary and unknown source.By comprehensively considering marker of the local source categories and the results of secondary PMF source apportionment of the fresh primary source,five local emission sources were determined.motor vehicle source was the largest contributor to primary fresh VOCs,accounting for 47.3%;the fourth local source category,the crude oil processing and petroleum products manufacturing industry,were the largest industry contributor with 23.5%;unknown source accounted for 11.8% and the firstcategory local industry and the second-category local industry contributed 9.6% and 7.8%,respectively.According to the results of source apportionment,motor vehicle source and crude oil processing and petroleum products manufacturing industry should be controlled strictly to decrease VOCs emission.