California Department of Transportation, Marysville, CA, USA.
Environ Sci Technol. 2010 Feb 1;44(3):1085-92. doi: 10.1021/es9019645.
Bioaugmentation to enhance the rate and extent of reductive dechlorination of chlorinated ethenes was investigated in intermediate ( approximately 1 m) scale physical aquifer models (PAMs) designed to simulate the groundwater flow field near an injection well. Push-pull tests were used to quantify the reductive dechlorination of injected trichloroethene (TCE) and trichlorofluoroethene (TCFE) in prepared sediment packs with and without an added dechlorinating culture containing Dehalococcoides spp. Distribution of the added culture throughout the sediment pack was confirmed by microscopic observation. Repeated additions of TCE (100-350 microM) were completely transformed to ethene in 14 days and a subsequent TCFE addition (114 microM) was completely transformed to fluoroethene (FE) in 24 days. Similar transformation rates, product distributions, and time courses for TCE and TCFE transformation were observed when these compounds were added together at similar initial concentrations. In the control PAM (nonbioaugmented), TCE and TCFE were transformed to only cis-DCE and cis-DCFE, respectively, and transformation rates were 6-12 times slower than those in the bioaugmented PAM. The use of TCFE for push-pull tests is shown to be an effective tool for detecting and quantifying the effects of bioaugmentation on TCE transformation.
生物强化以提高还原脱氯氯化乙烯的速率和程度，在中间（约 1 米）规模物理含水层模型（PAM）中进行了研究，这些模型旨在模拟注水井附近的地下水流动场。推拉测试用于量化注入的三氯乙烯（TCE）和三氯氟乙烯（TCFE）在准备好的沉积物包中的还原脱氯，其中包含或不包含添加的含有 Dehalococcoides spp. 的脱氯培养物。通过微观观察确认了添加的培养物在整个沉积物包中的分布。在 14 天内，重复添加的 TCE（100-350 μM）完全转化为乙烯，随后添加的 TCFE（114 μM）在 24 天内完全转化为氟乙烯（FE）。当这些化合物以相似的初始浓度一起添加时，观察到 TCE 和 TCFE 转化的相似转化速率、产物分布和时间过程。在对照 PAM（非生物强化）中，TCE 和 TCFE 仅转化为顺式-DCE 和顺式-DCFE，转化速率比生物强化 PAM 慢 6-12 倍。推拉测试中使用 TCFE 被证明是检测和量化生物强化对 TCE 转化影响的有效工具。
