SBIR Phase II: Enhanced Subsurface Injection of Chlorinated Solvent Degrading Microorganisms

该第二阶段SBIR项目包括开发、测试和模拟表面活性剂泡沫/细菌输送系统，用于就地修复稠密非水相液体(DNAPL)污染物。第一阶段研究证明了表面活性泡沫塑料技术与生物强化相结合对修复三氯乙烯(TCE)污染含水层的效果。这项初步工作的结果表明，泡沫塑料促进专门微生物向地下含水层沉积物的运输，将通过动员和分散DNAPL并运送可供生物降解的活生物来修复DNAPL。第二阶段研究的目标包括优化泡沫和细菌注射，以最大限度地提高DNAPL的冲刷能力，并提高细菌存活率和三氯乙烯的降解率。此外，这项技术将在以下方面进行测试：1)多种沉积物类型，2)风化沉积物，3)其他DNAPL污染物。从第二阶段工作中收集的数据将被用来开发一个数学模型，以预测DNAPL在田间条件下的命运(三氯乙烯动员的程度和三氯乙烯的降解速度)。该模型将用于确定影响地下水中三氯乙烯动员和降解的因素，并将用于设计和预测实地补救工作。这项技术的研究开发的潜在商业应用将导致一种具有成本效益的就地生物强化技术，即使是受三氯乙烯污染最严重的含水层也可以进行处理。氯化溶剂对含水层的污染是政府和工业场所最常见的环境责任之一，因此，能够经济有效地解决这一问题的工艺很可能在商业上取得成功。

This Phase II SBIR project involves the development, testing and modeling of a surfactant foam/bacterial delivery system for in situ remediation of dense non-aqueous phase liquid (DNAPL) contaminants. The Phase I study demonstrated the efficacy of combining a surfactant foam technology with bioaugmentation, to remediate trichloroethylene (TCE) contaminated aquifers. Results from this initial work suggested that foam facilitated transport of specialized microorganisms into subsurface aquifer sediments would result in the remediation of DNAPLs through mobilization and dispersion of the DNAPL and delivery of viable organisms for biodegradation. Objectives for the Phase II study include optimizing the foam and bacterial injection in order to maximize the scouring of the DNAPL and to enhance bacterial survival and TCE-degradation. In addition, this technology will be tested with: 1) numerous sediment types, 2) weathered sediment, and 3) other DNAPL contaminants. Data collected from the Phase II work will be used to develop a mathematical model to predict the fate of DNAPLs (extent of TCE mobilization and rate of TCE degradation) under field conditions. This model will be used to identify factors effecting the mobilization and degradation of TCE in the subsurface and will be used to design and predict field remediation efforts. Potential Commercial Applications of the Research Development of this technology will lead to a cost effective in situ bioaugmentation technology for treating even the most highly TCE-contaminated aquifers. Chlorinated solvent contamination of aquifers is one of the most common environmental liabilities at both government and industrial sites, therefore a process that can cost-effectively solve this problem will most likely be a commercial success.