EHCTM and EHC-M. - In Situ Chemical Reduction (ISCR) Technology for Treatment of Chlorinated Solvents and Metals
The Adventus Group (Adventus) has developed a combination of controlled-release solid carbon and zero valent iron (ZVI) particles to yield a highly effective material for stimulating the reductive dechlorination of persistent chlorinated organic solvents and heavy metals present in groundwater. The materials are known as EHC. And EHC-M. And can be employed as fill material for permeable reactive barriers or injected into groundwater and contaminant source zones in a variety of ways. Following placement of EHC into the subsurface environment, indigenous heterotrophic bacteria consume the organic component of EHC (processed fibrous organic material) and consume dissolved oxygen thereby reducing the redox potential in groundwater. In addition, these bacteria ferment carbon and release a variety of volatile fatty acids (acetic, propionic, butyric) into the groundwater plume which serve as electron donors for other bacteria. Finally, the small ZVI particles (I.e., between 10 and 50 mm) provide substantial reactive surface area that stimulates direct chemical dechlorination and an additional drop in the redox potential of the groundwater. These physical, chemical, and biological processes combine to create a strongly reducing (e.g., up to -550 mV Eh) environment that stimulates both chemical and microbiological dechlorination of solvents in groundwater as well as precipitation and stabilization of heavy metals. In situ chemical reduction (ISCR) is defined as the combined effect of stimulated biological oxygen consumption (via “fermentation of complex organic carbon sources), direct chemical reduction with reduced metals, and the corresponding enhanced decomposition reactions that are realized at the lowered redox (Eh) conditions. These combined effects are unique to EHC. Technology.
Fayaz LAKHWALA Jim MUELLER Josephine MOLIN John VALKENBURg Ravi SRIRANGAM
The Adventus Group–USA
国际会议
2009 International Symposium on Environmental Science and Technology(2009环境科学与技术国际会议)
上海
英文
2497
2009-06-02（万方平台首次上网日期，不代表论文的发表时间）