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DOI	10.5194/acp-20-13721-2020
	Chemical composition and light absorption of carbonaceous aerosols emitted from crop residue burning: Influence of combustion efficiency
	Wang Y.; Hu M.; Xu N.; Qin Y.; Wu Z.; Zeng L.; Huang X.; He L.
发表日期	2020
ISSN	1680-7316
起始页码	13721
结束页码	13734
卷号	20 期号:22
英文摘要	Biomass burning is one of the major sources of carbonaceous aerosols, which affects air quality, the radiation budget and human health. Field straw residue burning is a widespread type of biomass burning in Asia, while its emissions are poorly understood compared with wood burning emissions. In this study, lab-controlled straw (wheat and corn) burning experiments were designed to investigate the emission factors and light absorption properties of different biomass burning organic aerosol (BBOA) fractions, including water-soluble organic carbon (WSOC), humiclike substances (HULIS) and water-insoluble organic carbon (WISOC). The influences of biofuel moisture content and combustion efficiency on emissions are comprehensively discussed. The emission factors of PM2:5, organic carbon (OC) and elemental carbon (EC) were 9:3_3:4, 4:6_1:9 and 0:21_0:07 gkg1 for corn burning and 8:7_5:0, 3:9_2:8 and 0:22_0:05 gkg1 for wheat burning, generally lower than wood or forest burning emissions. Though the mass contribution of WISOC to OC (32 %-43 %) was lower than WSOC, the light absorption contribution of WISOC (57 %- 84% at 300-400 nm) surpassed WSOC due to the higher mass absorption efficiency (MAE) of WISOC. The results suggested that BBOA light absorption would be largely underestimated if only the water-soluble fractions were considered. However, the light absorption of WSOC in the near-UV range, occupying 39 %-43% of the total extracted OC absorption at 300 nm, cannot be negligible due to the sharper increase of absorption towards shorter wavelengths compared with WISOC. HULIS were the major light absorption contributors to WSOC, due to the higher MAE of HULIS than other high-polarity WSOC components. The emission levels and light absorption of BBOA were largely influenced by the burning conditions, indicated by modified combustion efficiency (MCE) calculated by measured CO and CO2 in this study. The emission factors of PM2:5, OC, WSOC, HULIS and organic acids were enhanced under lower MCE conditions or during higher moisture straw burning experiments. Light absorption coefficients of BBOA at 365 nm were also higher under lower MCE conditions, which was mainly due to the elevated mass emission factors. Our results suggested that the influence of varied combustion efficiency on particle emissions could surpass the differences caused by different types of biofuels. Thus, the burning efficiency or conditions should be taken into consideration when estimating the influence of biomass burning. In addition, we observed that the ratios of KC=OC and Cl=OC increased under higher MCE conditions due to the enhancement of potassium and chlorine released under higher fire temperatures during flaming combustion. This indicates that the potassium ion, as a commonly used biomass burning tracer, may lead to estimation uncertainty if the burning conditions are not considered. © Author(s) 2020.
语种	英语
scopus关键词	absorption; aerosol; aerosol composition; biomass burning; carbon; combustion; light effect; straw
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/247367
作者单位	State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China; Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Nanjing University of Information Science and Technology, Nanjing, China; Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, China; Beijing Innovation Center for Engineering Sciences and Advanced Technology, Peking University, Beijing, 100871, China
推荐引用方式 GB/T 7714	Wang Y.,Hu M.,Xu N.,et al. Chemical composition and light absorption of carbonaceous aerosols emitted from crop residue burning: Influence of combustion efficiency[J],2020,20(22).
APA	Wang Y..,Hu M..,Xu N..,Qin Y..,Wu Z..,...&He L..(2020).Chemical composition and light absorption of carbonaceous aerosols emitted from crop residue burning: Influence of combustion efficiency.ATMOSPHERIC CHEMISTRY AND PHYSICS,20(22).
MLA	Wang Y.,et al."Chemical composition and light absorption of carbonaceous aerosols emitted from crop residue burning: Influence of combustion efficiency".ATMOSPHERIC CHEMISTRY AND PHYSICS 20.22(2020).