郑州市典型工业企业VOCs排放特征及风险评估

为了解郑州市不同行业企业挥发性有机物(VOCs)污染特征及潜在危害,通过Summa罐和气袋采集样品,之后采用GC-MS/FID对样品进行测定分析.结果表明:郑州市包装印刷企业排放VOCs组分主要为含氧VOCs(OVOCs),包括乙酸乙酯和异丙醇,占比93.1%以上;汽车制造、家具制造和涂料生产企业VOCs组分主要为芳香烃,占比为33.5%～90.0%,以间/对-二甲苯、邻-二甲苯和乙苯为主;食品加工企业VOCs中卤代烃占比较高,为52.3%;橡胶企业VOCs主要为卤代烃和烷烃,占比分别为25.5%和28.8%;石墨碳素企业VOCs主要为芳香烃和OVOCs,占比分别为28.5%和24.1%.对比以往研究发现,郑州市与其他城市溶剂使用企业VOCs排放特征较为类似,但由于生产工艺及原辅料使用不同,相同行业企业中不同环节VOCs组分存在差异.风险评估结果显示,各企业排放的VOCs组分对臭氧生成潜势(OFP)和危害指数(HI)贡献具有一定正关联性,尤其苯、甲苯、乙苯及二甲苯等C_6～C_8芳香烃对OFP和HI贡献较大.汽车制造企业3号和家具企业5号HI值分别为1.18和2.74,均高于EPA规定限值,主要与该企业生产过程中使用溶剂型原辅料有关,且排放的主要以芳香烃为主,尤其苯、甲苯、乙苯、二甲苯和三甲基苯等C_6～C_9苯系物对HI和OFP的贡献较高,今后需重点管控溶剂型企业VOCs的排放.

Emission Characteristics and Risk Assessment of Volatile Organic Compounds from Typical Factories in Zhengzhou

To understand the characteristics and potential hazards of volatile organic compounds (VOCs) emitted from different industrial factories in Zhengzhou, several representative factories have been selected for sample collection using canisters; the samples were subsequently analyzed by GC-MS/FID system, from which the composition and risk of VOCs are discussed in this study. It was found that OVOCs, especially ethyl acetate and isopropanol, were the most important species originating from printing factories, which accounted for more than 93.1% of total VOCs. The major components related to manufacturing industries, including automobile, furniture, and coating, were aromatics, mainly m/p-xylene, o-xylene, and ethylbenzene, which contributed 33.5%-90.0% to VOCs. Halogenated hydrocarbons made the largest contribution (52.3%) to VOCs in the food processing industry. The main components of VOCs were halogenoalkanes (25.5%) and alkanes (28.8%) in rubber factories. As for graphite carbon factories, the main components of VOCs were aromatics (28.5%) and alkanes (24.1%). Compared with previous studies, the VOC emission characteristics of factories involving solvent usage in Zhengzhou are consistent with those in other cities, but the compositional information of VOCs varies across different factories, even within the same industry, due to the different production processes and raw materials used. Risk assessment showed that the concentration of VOCs emitted from solvent factories are positively correlated with ozone formation potential (OFP) and the hazard index (HI). Specifically, benzene, toluene, ethylbenzene, xylene, and other C₆-C₈ aromatic hydrocarbons contributed significantly to OFP and HI. The HI values were 1.18 and 2.74 in automobile manufacturing factory NO.3 and wooden furniture factory NO.5, respectively, which were higher than the limits stated by EPA regulations because of the different production processes and raw materials, and the VOCs of the factories were mainly composed of aromatics; in particular, C₆-C₉ benzene series contributed significantly to HI and OFP. Therefore, it is necessary to control VOCs originating from industries involving solvent usage.