利用醇類配合空氣注入法復育受有機物污染地下水之研究

A new method for air sparging on remediation of organic contaminants by adding alcohols into the groundwater

童科憲(Ke-Hsien Tung)

指導教授 ： 趙煥平

中原大學/工學院/生物環境工程研究所/碩士(2016年)

https://doi.org/10.6840/cycu201600542

摘要

空氣注入法與土壤蒸氣萃取法均為土壤地下水受到有機物污染時常見的處理方式，但可惜的是受限於有機物的揮發速率，若能有效增加有機物之揮發量，則能提高空氣注入法與土壤蒸氣萃取法之處理效率，本研究主要目標即為添加醇類至地下水中增加有機物在空氣注入法配合土壤蒸氣萃取法處理時的揮發量。
本研究使用的有機物包括常見由石化工業產生的直鏈型化合物(正己烷與正庚烷)與單環類芳香族化合物(苯、甲苯與乙苯)，同時也研究含氯有機溶劑(1,1,2-三氯乙烷與四氯乙烯)，所使用的醇類則包括正戊醇、正己醇與正庚醇，控制的條件則包含醇類濃度(2、6、10ppmv)、進氣流量(50ml/min)、抽氣流量(50ml/min)、土壤有機質含量，進行曝氣3小時後揮發之氣體將以商用吸附管進行收集，再以二硫化碳與正己烷進行萃取後注入氣相層析儀進行分析揮發質量，之後比較加入醇類與未加入之結果。
研究的結果顯示，醇類存在確實可以增加上述有機物之揮發量，其對揮發量影響大小呈現正庚醇＞正己醇＞正戊醇，且揮發速率隨著醇類濃度增加而增加，高有機質土壤會導致有機物傳輸效率受到抑制，且在揮發效率愈低的情況下愈明顯，最高的揮發增加比例為苯在彰化快官土與正庚醇添加10ppmv情況下之19.04倍，最高的揮發去除率為苯在桃園蘆竹土與正庚醇添加10ppmv情況下，去除率可達96.26%。

關鍵字

醇類 ； 有機物 ； 揮發 ； 空氣注入法

並列摘要

Air sparging (AS) and soil vapor extraction (SVE) are frequently used to remediate contaminated soil and groundwater by organic compounds. When the target contaminants are low volatile organic compounds, it will be a very long schedule to finish the remediation. In this study, a novel method was presented to increase emissions of organic compounds and improve the remediation schedule for removal efficiencies of organic contaminants. The objective of this study is to add alcohol to groundwater for the increase in volatilization of organic compounds in the processes of AS and SVE.
The target organic compounds include aliphatic compounds (n-hexane and n-heptane), aromatic compounds (benzene, toluene and ethylbenzene) and chlorinated organic compounds (1,1,2-trichloroethane and tetrachloroethene). The n-pentanol, n-hexanol and n-heptanol with 2, 6 and 10ppmv were added the solution mixing with a target organic compound. Air flow rate was set as 50 ml/min. The two kinds of soil with different organic matter content were used to examine the transportation of the test organic compounds in the soils..
The result indicated the added alcohols can effectively increase the volatilization of the VOCs. The volatile amounts of VOCs increase with the increasing alcohol concentrations. The volatilation amounts of test organic compounds were in the descreasing order : n-heptanol > n-hexanol >n-pentanol. When n-heptanol with 10 ppm was added in the system, the highest ratio of volatilization enhancement can reach 19 for benzene. The soil with high organic matter might reduce the volatilization of VOCs in the soil-water system. The best removal efficiency for aromatic compounds is 96.26%.

並列關鍵字

Alcohol ； organic compounds ； volatilization ； air sparging

參考文獻

蕭松旺，“醇類對水中有機溶質揮發影響之研究”，碩士論文，中原大學土木工程學系生物環境工程組，中壢市(2011)。

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