| 摘要: | 本研究以南部某石化工業區廢水處理廠之廢水收集系統為研究對象，進?廢水中可逸散之揮發性有機物特性之採樣分析及處理效能評估。研究結果顯示進流水逸散之揮發性有機物種，被檢測出84種揮發性有機物質中，本石化業廢水處理廠以苯環揮發性有機物(乙苯、鄰-二甲苯、間,對-二甲苯、甲苯、苯、苯乙烯)及鹵烷類揮發性有機物(四氯乙烯、氯苯、三氯乙烯、四氯化碳、1,2-二氯乙烷、氯仿)為主，進流水逸散之TVOCs濃度介於 874.9 ~ 98.3 ppm之間。本研究同時針對廢水逸散之VOCs進行控制，在去除逸散氣體之水氣前後，獲得差異相當大之VOCs削減率，研究顯示去除水氣後活性碳之吸附效果能有效提升。此外，進流逸氣與不同臭氧供應條件下（15 L/min、30 L/min、45 L/min）混合氧化後之處理效果，研究顯示臭氧15 L/min，削減率為62.3% ~ 78.7% 之間；臭氧30 L/min，削減率為71.8%~85.4% 之間；臭氧45 L/min，削減率為71.4% ~ 97.3% 之間。再進一步結合臭氧（15 L/min、30 L/min、45 L/min）氧化及活性碳吸附之效果，研究顯示，臭氧 15 L/min氧化及活性碳吸附削減率為83.8 ~ 99.0%，平均為95.0%；臭氧 30 L/min氧化及活性碳吸附削減率為86.1 ~ 96.3%，平均為92.7%；臭氧45 L/min氧化及活性碳吸附削減率為91.1% ~ 99.3%，平均為96.0%。在本研究試驗中，在活性碳吸附前，若能先去除水氣，將有效提升活性碳吸附效果，並延長使用壽命；臭氧氧化揮發性有機物條件，考慮臭氧產生量提高時削減率卻無明顯差異，因此試驗中臭氧30L/min氧化為最適條件；再進一步結合臭氧氧化及活性碳吸附條件，在試驗中削減率平均比較結果中，考慮氧化15 L/min結合活性碳吸附時遇高濃度有機物時雖可達良好吸附效果，但仍比45 L/min時差，且臭氧45 L/min氧化結合活性碳吸附效果較為穩定，故試驗中臭氧45L/min氧化結合活性碳吸附為最適條件。
In this study, volatile organic compounds (VOCs) in the raw wastewater collection system of a wastewater treatment plant at a petrochemical industrial park in Southern Taiwan were sampled and analyzed to evaluate the performance of outgassing treatment. First, stainless steel bottles were used to sample gas for analyzing various species of VOC. Considering the high relative humidity of the gas, activated carbon adsorption and ozonation were applied under varying water vapor conditions. Subsequently, activated carbon adsorption and ozonation procedures were combined and assessed for its effectiveness in removing VOCs following the removal of water vapor from VOCs. The study results show that among the 84 types of VOC detected in the wastewater inflow fugitive species sample, benzenic VOCs (ethylbenzene, o-xylene, m,p-xylene, toluene, benzene, and styrene) and alkyl halide VOCs (tetrachloroethene, chlorobenzene, trichloroethylene, carbon tetrachloride, 1,2-dichloroethylene, and chloroform) were the most common. The concentration of fugitive total VOCs in the inflowing water ranged between 98.3 and 874.9 ppm.When the fugitive VOCs in the wastewater were controlled, the reduction rate results differed significantly before and after removing the water vapor from the fugitive gas. The studied effect shows that the adsorption results of the activated carbon can be improved after removing the water vapor (on average, the reduction rate increased to 72.8%). In addition, regarding the inflow outgassing treatment effects under different ozone supply conditions and after mixing with oxides, the reduction rates were 62.3%–78.7%, 71.8%–85.4%, and 71.4%–97.3% at ozone production rates of 15, 30, and 45 L/min, respectively.Regarding the serial treatment effects obtained from combining ozonation and activated carbon adsorption, the total VOC reduction rates by oxidation and adsorption were 83.8%–99.0% (average: 95.0%), 86.1%–96.3% (average: 92.7%), and 91.1%–99.3% (average: 96.0%) for ozone generation rates of 15, 30, and 45 L/min, respectively.In the test performed in this study, when water vapor interference was removed before conducting VOC adsorption treatment with activated carbon, the adsorption effect was effectively enhanced, thus prolonging its utility. An ozone production rate of 30 L/min was the optimal oxidation condition in the test. Further combined with the ozonation and activated carbon adsorption conditions, the ozone production rate of 45 L/min produced a more stable treatment effect. |
