关中住宅燃煤排放 PM_2.5 中 NACs 污染特征及吸光特性

In order to investigate the differences in the molecular composition, regional emission and light absorption contribution of nitrated aromatic compounds (NACs) produced by different combustion methods of residential coal in rural areas of Guanzhong Plain, bituminous coal and anthracite were selected as fuels. Based on the field stove and dilution sampling system, the characteristics of (NACs) emissions from coal combustion were studied by using ultra-high performance liquid phase and four-pole time-of-flight mass spectrometry. The results show that the average emission factor of ΣNACs (EF_ΣNACs) during coal combustion in Guanzhong area was 3.7mg/kg, in which bituminous briquette (7.5mg/kg) > anthracite briquette (2.7mg/kg) = bituminous coal (2.7mg/kg) > anthracite (1.7mg/kg), the EFΣ_NACs produced by coal combustion in different stoves were significantly different. In traditional stoves, the EF_ΣNACs emitted by bituminous briquettes were the highest, followed by anthracite briquettes and bituminous raw coal, and anthracite raw coal was the lowest. The EF_ΣNACs from bituminous briquette decreased the most after the use of air distribution furnace. The light absorption value of ΣNACs at 365nm was bituminous briquette traditional stove > anthracite briquette traditional stove > bituminous briquette air distribution furnace > anthracite air distribution furnace > bituminous traditional stove > anthracite traditional stove > anthracite traditional stove. In this paper, the total emission of ΣNACs from coal combustion in five cities of Guanzhong Plain in 2019was estimated to be 198.8t, with Weinan (91.6t) > Xi'an (32.2t) > Xianyang (29.2t) ≈ Baoji (29.0t) > Tongchuan (16.8t).