Dual-Biofilm Reactive Barrier for Treatment of Chlorinated Benzenes at Anaerobic-

用于在厌氧条件下处理氯化苯的双生物膜反应屏障

• 批准号: 8757453
• 负责人: Edward Bouwer
• 金额: $ 16万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-10 至 2018-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8757453
• 关键词: Address; Aerobic; Aerobic Bacteria; Affect; Amendment; Bacteria; Benzene; Biodegradation; Biological Availability; Bioremediations; Carbon; Carbon Dioxide; Carcinogens; Chlorobenzene; Communities; Compost; Effectiveness; Electron Microscopy; Environment; Environment and Public Health; Environmental Risk Factor; Exposure to; Goals; Growth; Hazardous Waste Sites; Health; Human; In Situ; Inorganic Sulfates; Kinetics; Laboratories; Liquid substance; Methods; Microbial Biofilms; Nature; Nitrates; Oxidants; Oxidation-Reduction; Pathway interactions; Performance; Phase; Population; Process; Research; Research Design; Risk; Sampling; Scientific Advances and Accomplishments; Series; Shock; Site; Soil; Source; Spectrum Analysis; Surface; System; Technology; Temperature; Testing; Unspecified or Sulfate Ion Sulfates; Validation; Water; Work; analytical method; aqueous; chlorobenzene; dechlorination; drinking water; feeding; innovation; innovative technologies; microbial; microbial community; microorganism; organic contaminant; performance site; remediation; research study; superfund site; uptake

DESCRIPTION (provided by applicant): The proposed project comprises mechanistic research to assess the biogeochemical interactions that affect bioavailability of chlorinated benzenes (CBs) during in situ remediation of CB-contaminated groundwater and sediments using a dual-biofilm barrier approach. The dual-biofilm barrier innovatively combines both an anaerobic dehalogenating consortia and aerobic oxidizing bacteria, seeded on granular activated carbon (GAC), to achieve complete transformation of higher chlorinated benzenes to carbon dioxide, which otherwise commonly stalls at formation of monochlorobenzene and benzene upon reductive dechlorination of higher chlorinated benzenes. The overall goals of this proposed project are to further the scientific and technical advancement of this innovative technology and to demonstrate its effectiveness in protecting ecological and human health by treating contaminants in situ and reducing their mass flux to surface water or in subsurface plumes that are potential drinking water sources. Laboratory and field tests will be conducted using a Superfund site where dense non-aqueous phase liquid (DNAPL) CB contamination is present in wetland sediments and groundwater, and preliminary studies have been performed on the contaminant distribution and degradation processes. The effectiveness of this biobarrier technology to serve as a long-term remedy at this Superfund site and other hazardous waste sites depends on several factors, including biogeochemical interactions and dynamics with the biofilm, other biobarrier components, the underlying sediment, and the inflowing groundwater. These factors will be investigated through studies designed to address five specific aims: (i) determine the stability and effectiveness of aerobic and anaerobic biofilms on GAC through microcosm experiments under shock loading conditions and employing electron microscopy and surface spectroscopy to characterize the surfaces; (ii) examine the interactions between unseeded GAC and the site matrix (sediment and water) in batch experiments to assess contaminant sorption / desorption kinetics by utilizing aqueous phase speciation and surface characterization methods; (iii) investigate biodegradation processes and rates of CBs in replicate upflow column experiments that compare unseeded GAC to GAC seeded with only an anaerobic culture and both the aerobic and anaerobic cultures to assess the dual-biofilm effectiveness in treating CBs; (iv) assess the impacts of different electron acceptors and other biogeochemical conditions on degradation rates of CBs in upflow column experiments to establish conditions that optimize barrier efficiency and performance; (v) evaluate on-site performance of the dual-biofilm barrier through field tests to determine biofilm effectiveness and sustainability over a multi-year period under realistic hydrologic and biogeochemical dynamics and environmental conditions.

描述（由申请人提供）：拟议项目包括机械研究，以评估在使用双生物膜屏障方法原位修复受氯化苯（CB）污染的地下水和沉积物期间影响氯化苯（CB）生物利用度的生物地球化学相互作用。双生物膜屏障创新性地结合了厌氧脱卤菌群和好氧氧化细菌，接种在颗粒活性炭（GAC）上，以实现将高级氯化苯完全转化为二氧化碳，否则二氧化碳通常会在还原时停止形成一氯苯和苯高级氯化苯的脱氯。该拟议项目的总体目标是进一步推动这一创新技术的科学和技术进步，并通过原位处理污染物并减少其向地表水或潜在地下羽流的质量通量来证明其在保护生态和人类健康方面的有效性。饮用水源。实验室和现场测试将在湿地沉积物和地下水中存在浓密非水相液体 (DNAPL) CB 污染的超级基金场地进行，并对污染物分布和降解过程进行了初步研究。这种生物屏障技术作为超级基金场地和其他危险废物场地的长期补救措施的有效性取决于几个因素，包括生物地球化学相互作用以及与生物膜、其他生物屏障成分、底层沉积物和流入地下水的动态。这些因素将通过旨在解决五个具体目标的研究进行调查：（i）通过冲击载荷条件下的微观实验并采用电子显微镜和表面光谱来表征表面，确定 GAC 上需氧和厌氧生物膜的稳定性和有效性； (ii) 在批量实验中检查未接种的 GAC 与位点基质（沉积物和水）之间的相互作用，以利用水相形态和表面表征方法评估污染物吸附/解吸动力学； (iii) 在重复上流柱实验中研究生物降解过程和CB的速率，该实验将未接种的GAC与仅接种厌氧培养物以及需氧和厌氧培养物的GAC进行比较，以评估双生物膜处理CB的有效性； (iv) 评估上流柱实验中不同电子受体和其他生物地球化学条件对CB降解速率的影响，以建立优化屏障效率和性能的条件； (v) 通过现场测试评估双生物膜屏障的现场性能，以确定生物膜在现实水文和生物地球化学动力学和环境条件下多年的有效性和可持续性。