SBIR-STTR Award

Municipal wastewater treatment plants represent a huge energy 'sink' in the United States. Estimates are that these plants consume up to 3 percent of the total amount of power consumed annually. Ironically, the wastewater is concentrated with materials (carbohydrates) which inherently are high energy compounds. Novel research with Microbial Fuel Cell (MFC) technology has demonstrated an ability to extract this chemical energy contained in wastewater and convert it to electrical power. Chemical energy extracted from wastewater carbohydrates has the potential, in theory, to convert wastewater treatment plants from huge power users to sources of electrical power. This effort is proposed to bring to market MFC technology which could have a radically positive effect on a huge energy-consuming industry in the U.S. and the world. Fuss & O'Neill, using engineering research conducted at the University of Connecticut (UConn), will demonstrate the feasibility of an innovative approach to achieve three of the U.S. Environmental Protection Agency's (EPA) goals for wastewater facilities: reducing energy requirements, better managing energy use, and the cost-effective production and recovery of renewable energy (green power) (under the EPA SBIR Solicitation Category E). Fuss & O'Neill's SBIR Phase I project will successfully apply the fundamental mechanisms of MFC technology to wastewater treatment, which is believed to have a revolutionary significance for the wastewater industry. This technology has the potential to generate sufficient power to operate a host treatment facility without adding or requiring additional energy. In short, it would have the potential to achieve environmental goals in an energy self-sufficient manner. Ongoing MFC research at UConn has demonstrated that electrical power is produced as renewable energy through the contaminant removal in wastewater treatment without adding extra chemical catalysts. This holds a great promise of transforming wastewater treatment facilities into green power plants. The 16,000 public wastewater treatment systems in the United States account for approximately 2-3% of the nation's electric load. As population grows and environmental requirements become more stringent, the demand for energy in water and wastewater is expected to grow by up to 20% during the next 15 years. Developing new approaches to reduce energy consumption in wastewater treatment systems is critical for environmental sustainability. Bioelectricity generation in MFCs is a promising solution, since it utilizes anaerobic bacteria to convert contaminants in wastewater to electricity. It is expected that the energy contained in wastewater nationwide can meet the requirements of more than 100 million people. MCFs treating wastewater will be a significant step toward environmental sustainability in the New England area

Wastewater treatment facilities serve a critically important environmental and public health function, but do so at a very high cost. Implementation of microbial fuel cell (MFC) technology in wastewater systems could change the fundamental energy budget of treatment nationwide. The Phase I SBIR project, entitled "Electricity Generation from Anaerobic Wastewater Treatment in Microbial Fuel Cells (MFCs)," successfully demonstrated that MFCs can treat municipal wastewater and generate electricity simultaneously. In this pilot-scale project, which had considerable outside funding, a multi-anode/cathode granular activated carbon-based MFC (MAC-GACMFC) was designed, constructed, operated, and modified to treat municipal wastewater at temperatures of 25 to 30°C with a hydraulic retention time of 20 hours and external resistances of 100 ohm. Electrical power was produced, and effluent chemical oxygen demands (CODs) less than 50 mg/L were achieved in continuous-flow anaerobic MAC-GACMFC systems treating primary effluent. In the proposed Phase II scope of work, two major tasks will be conducted to optimize MFC operation and improve power generation for future commercialization. In the first task, the MAC-GACMFC capabilities will continue to be tested at alternate operating conditions in order to develop a rational basis for design. Specifically, the first task will: * Determine treatment performance with primary effluent as the substrate; * Examine performance with higher strength dairy-based wastewaters; * Determine performance impacts at lower temperatures; * Investigate performance at alternate hydraulic retention time (HRT) levels; and * Examine the impact of alternate external resistance levels. In the second task, the MFC system configurations and materials will be modified and developed with the objectives of improving power generation and treatment efficiency and developing a practical, cost-effective commercial product. The design improvements will be critical to commercializing the technology. Specifically, the second task will address: * Improvements to anode/cathode pairs to minimize internal resistance and improve access for maintenance and repair; * Optimizing anode to cathode ratios and anode density in the GAC bed; and * Testing alternate (lower cost) catalyst coatings on the cathode material to replace the costly platinum coating. Lab-scale tests have shown encouraging results with alternative catalysts. The anticipated results of Phase II will be used to develop a greatly improved and engineered MFC system for future commercialization. In the opinion of the Project Team, this unique MFC technology has great potential to be developed as a modularized system, enhancing its feasibility as a cost-effective, practical retrofit for municipal wastewater treatment systems. Supplemental

Keywords:
small business, SBIR, EPA, wastewater treatment, microbial fuel cells, granular activated carbon, GAC, MAC-GACMFC, power generation, anaerobic, dairy-based wastewaters, alternative catalysts, water pollution, electrical power, water infrastructure rehabilitation, power generation