Source apportionment of black carbon and combustion-related CO 2 for the determination of source-specific emission factors

[摘要] Black carbon (BC) aerosol typically has two major sources in the urban environment: traffic and domestic biomass burning, which has a significant contribution to urban air pollution during the heating season.Traffic emissions have been widely studied by both laboratory experiments(individual vehicle emission) and real-world measurement campaigns (fleetemission). However, emission information from biomass burning is limited,especially an insufficiency of experimental results from real-world studies.In this work, the black carbon burden in the urban atmosphere wasapportioned to fossil fuel (FF) and biomass burning (BB) related componentsusing the Aethalometer source apportionment model. Applying the BC sourceapportionment information, the combustion-related CO 2 was apportionedby multilinear regression analysis, supposing that both CO 2 components should be correlated with their corresponding BC component. The combinationof the Aethalometer model with the multilinear regression analysis (AM-MLR) provided the source-specific emission ratios (ERs) as the slopes of thecorresponding BC–CO 2 regressions. Based on the ER values, the source-specific emission factors (EFs) were determined using the carboncontent of the corresponding fuel. The analysis was carried out on a 3-month-long BC and CO 2 dataset collected at three monitoring locations in Ljubljana, Slovenia, between December 2019 and March 2020. The measured mean site-specific concentration values were in the 3560–4830 ng m −3 and 458–472 ppm ranges for BC and CO 2 , respectively. The determined average EFs for BC were 0.39 and 0.16 g(kg fuel) −1 for traffic andbiomass burning, respectively. It was also concluded that thetraffic-related BC component dominates the black carbon concentration(55 %–64 % depending on the location), while heating has the major share inthe combustion-related CO 2 (53 %–62 % depending on the location). Themethod gave essential information on the source-specific emission factors ofBC and CO 2 , enabling better characterization of urban anthropogenicemissions and the respective measures that may change the anthropogenicemission fingerprint.

[学科分类] 内科医学