粉煤炉电厂烟气颗粒物中多环芳烃的赋存特征及源解析意义

Occurrence of polycyclic aromatic hydrocarbons in inhalable particulate matters emitted from pulverized coal boilers of coal-fired power plant and source apportionment implications

针对安徽淮南3家粉煤炉燃煤机组排放的烟气,分析了可吸入颗粒物(PM_(2.5–10)、PM_(1–2.5)、PM_(1))中多环芳烃(PAHs)的浓度和组成及PAHs单体同位素的值.研究表明,烟气颗粒物中PAHs排放浓度主要受锅炉类型、燃烧参数和大气污染控制设施等因素的影响.细颗粒物易富集PAHs,且对高分子量PAHs的富集程度更高.不同粒度颗粒物中PAHs特征比值的变化幅度较小,但对不同燃煤源排放的PAHs仍有较大的不确定性.PAHs单体碳同位素值有效区别燃煤锅炉源、生物质燃烧和车辆尾气排放源,但对于粉煤炉的不同燃烧过程指示不明显.

The concentrations,distributions,and stable carbon isotope compositions of polycyclic aromatic hydrocarbons(PAHs)in inhalable particulate matters(PM_(2.5-10)、PM_(1-2.5)andPM_(1))emitted from three pulverized coal boilers of coal-fired power plants(CFPPs)in Anhui,China were investigated.Results indicate that PAH concentrations and distributions in PM_(2.5-10)、PM_(1-2.5) and PM_(1) were affected by the boiler type and operating conditions of air pollution control devices.The fine particles tended to enrich high molecular weight PAHs compared to coarse particles.The diagnostic ratios of PAHs varied insignificantly among different boilers,suggesting a potential to trace CFPP-based combustion sources in the environment.However,they can not be used to trace emission sources from different types of coal boilers of CFPPs due to their large variations.The stable carbon isotope compositions of PAHs showed significant variations among the emission sources of CFPPs,biomass burning,and vehicle exhaust.They varied insignificantly in the processes of PAH formation during coal combustion from pulverized coal boilers and the subsequent transfer of flue gas.