Characteristics And Control Of VOCs Emission From Typical Electronic Products Processing And Manufacturing Factory

As the rapid development of global electronic product market, VOCs emissioncaused by the processing and manufacturing of electronic products has become one ofthe most important factors that influences urban ambient air quality in some Chinesecities. Being an emerging industry, currently there is less research that has been carriedout regarding its VOCs problem, therefore this research aims to obtain the VOCsemission characteristics of electronic products’ processing and manufacturing processesthrough on site research and sampling, and provide technical suggestion on its VOCscontrol by thoroughly analyzing available treatment equipment in market. And theinfluence on VOCs emission of ventilation system in painting room was simulated byusing Computational Fluent Dynamic (CFD), with which an optimized venting scenariowas selected. In addition, suggestions on VOCs regulating and management in Chinawere provided through case-studying of the system in the United States and comparingthe situation with China.In this research, fast VOCs detector was applied in combination with samplingmethods of Summa canister and DNPH absorbent to identify the key emission processand qualify the VOCs species distribution, as well as quantify the concentration ofBTEX and ketone during the processing and manufacturing of electronic products. Theresults showed that in all processes that involve VOCs release, concentrations of totalVOCs in the workshops are0.1-0.5mg/m~3,1.5-2.5mg/m~3and20-200mg/m~3forcasting, cutting and painting respectively, indicating painting is the main emissionprocess. Over20different species were detected in those workshops, including alkanes,eneynes, aromatics, ketones, esters and ethers, in which BTEX and ketone are mainspecies emitted in painting process. The annual total emission caused by paintingprocess is840t in the whole factory.By analyzing the existing VOCs control technique and commercially availabletreatment equipment, two treating methods with plasma remover and zeolitepre-concentrator as key VOCs removing elements respectively were provided based onthe theory of end control. In order to make use of the ventilation system in paintingroom, four different venting scenarios were designed and simulated and the result indicated that with an air supply speed of0.8m/s and exhaust speed of0.4m/s, theefficiency of VOCs exhausting system can be maximized and the ambient VOCsconcentration in the painting room can be minimized.Realizing the current existing regulation related to VOCs emission in China cannot be reasonably used as control criteria for electronic product processing andmanufacturing, which has lead to severe pollution problem in certain area. As a result,by learning the U.S. regulations system of air pollution control and analyzing the VOCsmanagement scheme in China, the regulating situation for processing andmanufacturing of electronic products industry was assessed. In according to theliterature research of all the regulating and management systems both in U.S. and China,suggestions from the point of view of overall structure of environment legislation, airpollution law system and VOCs regulation system were provided regarding the VOCsemission problem in China as well as in electronic products’ processing andmanufacturing industry.