轻型汽车和汽车塑料配件涂装工艺过程的VOCs组分特征

通过采集和分析珠江三角洲(以下简称“珠三角”)地区轻型汽车和汽车塑料配件涂装工艺过程的VOCs样品,识别了上述两个行业不同涂装工艺过程的VOCs组分特征.结果表明:芳香烃(56.4%~75.5%)和OVOCs(11.0%~35.7%)为轻型汽车涂装工艺占比最大的两种VOCs组分;烷烃和烯炔烃在烘干工艺所占比重要高于喷涂工艺;1,2,4-三甲苯为电泳和面涂烘干工序的主要VOCs组分,间/对-二甲苯、乙酸丁酯、丙二醇甲醚醋酸酯分别为中涂、面涂和中涂烘干工序的主要VOCs组分.汽车塑料配件涂装工艺不同工序的VOCs组成相似,芳香烃(53.3%~58.3%)和OVOCs(40.9%~45.8%)为主要VOCs组成,甲苯、乙酸乙酯、乙酸丁酯等为主要VOCs组分.不同废气治理设施对汽车塑料配件涂装工艺VOCs组分会造成一定的影响.活性炭吸附治理设施处理后的主要VOCs组分为甲苯、乙苯和邻二甲苯等芳香烃组分,水喷淋治理设施则为乙酸乙酯、乙酸丁酯和丙二醇甲醚醋酸酯等OVOCs类组分.通过与其他研究对比,丙二醇甲醚醋酸酯作为原辅料和废气中的主要组分之一,在以往研究中并未识别出来,表明针对测试对象的原辅料与工艺信息的现场调研是开展VOCs组分特征及成分谱研究的基础工作,建议未来该方面研究加强对前期调研工作的重视.此外,建议关注行业发展趋势给VOCs成分谱研究带来的影响.

Process-based emission characteristics of volatile organic compounds(VOCs) from light vehicle and auto plastic parts manufacturing industry

Species profiles of VOCs emission from different processes of the light vehicle and auto plastic parts manufacturing industry in the Pearl River Delta (PRD) region were identified via field sampling and analysis. As revealed in this study, aromatics (56.4%~75.5%) and OVOCs (11.0%~35.7%) were the two major components in the coating processing of the light vehicle manufacturing industry. The percentages of alkanes and alkenes in the drying process were much larger than those in the coating process. 1,2,4-trimethylbenzene was the dominant species in the electrodeposition coating and top coat drying process. m/p-Xylene, butyl acetate and 1-methoxy-2-propyl acetate were the major species in the intermediate coating, intermediate coat drying and top coating process, respectively. In term of coating processes in the auto plastic parts manufacturing industry, aromatics (53.3%~58.3%) and OVOCs (40.9%~45.3%) were the major VOCs components, and toluene, ethyl acetate and butyl acetate were the dominant species. Besides, the major aromatics species emitted from activated carbon treatment facilities of the auto plastic parts manufacturing industry were toluene, ethyl-benzene and o-Xylene, while the major aromatics species from water spray treatment facilities were ethyl acetate, butyl acetate and 1-methoxy-2-propyl acetate. 1-methoxy-2-propyl acetate, one of the major species from raw materials and exhaust gas, was identified in this study but not in previous studies in China. This study showed that a full field investigation of raw material and process information of the test object is the first step in investigating characteristics of VOCs component and source profiles. Moreover, attentions should be paid to the influence of industrial development trend on the changes of VOCs source profiles.