Pilot study of trichloroethene-contaminated aquifer using vegetable oil emulsion.

• Main Authors: Jing-Hua Sung, 宋景樺
• Other Authors: 張書奇
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/69136558638548289720

碩士 === 國立中興大學 === 環境工程學系所 === 101 === The family of chlorinatd ethenes has been widely used as a solvent and building block in industrial and pharmaceutical manufacturing. Some of the most common chlorinated alipathic hydrocarbons （CAHs） found in groundwater include perchloroethene （PCE）, trichloroethene （TCE）, 1,1,1-trichloroethane （1,1,1-TCA）, carbon tetrachloride （CT）. Enhanced reductive bioremediation （ERB） of halogenated organics has been appliedto reduce CAHs in groundwater. ERB involves the addition of carbon substrates to the subsurface to stimulate anaerobic bacteria capable of reductively dechlorinating CAHs. In this processes, CAHs play the roles as electron accepters, while an electron donor is required to provide energy. Researchers are developing all different kinds of electron doners. Vegetable oil emulsion is one of them that can slowly release hydrogen in the subsurface to enhanced reductive bioremediation. Our study focuses on the first phase of anaerobic reductive dechlorination reactions applying a self-developed soybean oil emulsion for a pilot study. We conducted two experiments on the site. From the first experiment, we know that monitoring wells MW-1 was not affected by injection well IW-1. So we changed the injection methods to improve the radius of influence of the emulsion. In addition to chemical analysis such as CAHs, daughter compounds, inorganic compounds, and total organic carbon, total count of bacteria and denaturing gradient gel electrophoresis were alos performed. We found that in injection wells IW-1 and IW-2, 21 days after the injection, TCE concentrations were already less than detection limit. In IW-2, 1,1-DCE dropped from 127.2 μg/L to 27.3 μg/L 95 days after injection. Thus we confirmed that this soybean oil emulsion can effectively enhanc 1,1-DCE and TCE biodegradation in a real world situation.