This proposal brings together Hampton Roads Sanitation District and the University of Michigan to develop a sensor-mediated control strategy for achieving efficient nitrogen removal from next generation mainstream wastewater systems, and to demonstrate that strategy through pilot-scale systems. The nitrogen removal technologies being considered are novel and undeveloped for mainstream implementation, but hold great promise by significantly reducing the energy, carbon and land footprint of treatment processes that meet stringent nutrient regulations for a significant percentage of the U.S. wastewater flow. To fully understand how sensor-mediated control strategies confer sustained performance and resiliency to microbiological communities that comprise these treatment systems, a strong university partnership is needed. In the bioreactors being evaluated, University of Michigan will be responsible for performing molecular microbiological analyses to evaluate the impact of sensor-mediated control strategies on the composition and metabolic function of the microbial consortia. Experimental lab-scale systems will be operated at University of Michigan while existing pilot-scale systems will be operated at both University of Michigan and Hampton Roads Sanitation District. All experimental systems will be fully automated with sensor-mediated control strategies. Performance-based computational models will be developed during the first year and further refined in subsequent years to develop a useful design tool for the industry to use once these technologies are implemented. One or more graduate students will be funded on this project and will work both on-campus and at Hampton Roads Sanitation District over the course of their Ph.D. degree program. The industrial co-PI will serve as co-advisor to the graduate student(s). This project will demonstrate a utility-university research partnership that will serve as a national model.
There has been rapid development of sidestream treatment of ammonia-ladened wastewaters that use nitrite repression to prevent complete ammonia oxidation, and anaerobic ammonia oxidation (anammox) to remove N. However, comparable development for mainstream treatment where the ammonia concentrations are more than an order of magnitude lower and flows are vastly larger has not occurred. There are unique challenges to implementing sensor-mediated partial ammonia oxidation, nitrite repression (NOB out-selection) and anammox at the mainstream that will be addressed through this project. The PIs will also address denitrifying anaerobic methane oxidation, a new microbial metabolism, as well as anaerobic sulfide oxidation. The team will evaluate the impact that sensor-mediated control strategies have on the structure and function of microbial communities that comprise these systems. This, in turn, will advance our broader understanding of sensor-mediated control strategies for wastewater treatment at a mechanistic level. Due to the collaborative effort in advancing use of sensor-mediated control strategies with next-generation treatment systems, the research team is more likely to get "buy-in" from an industry that has traditionally been wary of advanced automation.
