兰州市化石燃料燃烧源排放VOCs的臭氧及二次有机气溶胶生成潜势

随着我国工业的快速发展和城市化进程的加快,化石燃料的大量使用造成了严重的二氧化硫、颗粒物和挥发性有机物(volatile organic compounds,VOCs)等大气污染.目前,对化石燃料燃烧排放挥发性有机物环境影响的研究较少,本文计算了兰州市化石燃料燃烧源排放VOCs及其相应的臭氧生成潜势(ozone formation potential,OFP)和二次有机气溶胶生成潜势(secondary organic aerosols formation potential,SOAFP),其中水泥制造业的OFP和SOAFP占比最大,分别为45. 3%、50. 9%;其次为砖瓦制造业,但其吨标煤燃烧排放VOCs的OFP和SOAFP值最高,折为吨标煤后天然气燃烧产生VOCs的O_3和SOA最小.兰州市主城区化石燃料燃烧源OFP和SOAFP主要为电力和热力的生产供应以及西固区工业企业排放VOCs的贡献,其它地区为水泥制造业、砖瓦制造业、钢铁冶炼业等高能耗的行业的贡献为主.芳香烃是化石燃料燃烧源排放VOCs中对OFP和SOAFP均贡献最大的一类物质,占比分别为40. 0%和67. 2%,并且在生成潜势贡献前10的物种中芳香烃为主要物种.与生物质燃烧源相比,化石燃料燃烧源具有较强的O_3和SOA生成能力(2. 58 t·t~(-1)和3. 16 kg·t~(-1)).

Formation Potential of Ozone and Secondary Organic Aerosol of VOCs from Fossil Fuel Combustion in Lanzhou City

With the rapid development of China''s industry and the acceleration of urbanization, the massive use of fossil fuels has increased the concentration of air pollutants such as sulfur dioxide, particulate matter, and volatile organic compounds (VOCs) in the cities. However, there is little research on the environmental impact of volatile organic compounds from fossil fuel combustion emissions. In this paper, ozone formation potential(OFP)and secondary organic aerosol formation potential (SOAFP) of VOCs from fossil fuel combustion in Lanzhou city were calculated. The OFP and SOAFP of the cement industry were the largest, representing 45.3% and 50.9%, respectively, followed by brick and tile industries. However, when the calculations were based on tons of standard coal equivalent, the largest contributors to OFP and SOAFP of VOCs emitted from combustion were the brick and tile industries, and the smallest was the natural gas industry. VOCs from fossil fuel combustion of power plants and industry enterprises in the Xigu District are the main contributors to the OFP and SOAFP in the urban district of Lanzhou city. The contribution rates of the aromatic hydrocarbons from fossil fuel to OFP and SOAFP account for 40.0% and 67.2%, respectively. Aromatic hydrocarbons are also the main component in the top 10 species that contribute to OFP and SOAFP. The mass ratio of OFP and SOAFP per VOCs from fossil fuel combustion (2.58 t·t^-1, 3.16 kg·t^-1) is larger than those from biomass combustion (2.22 t·t^-1, 1.38 kg·t^-1).