Technical Approach

The novel approach pursued in this research utilizes three sustainable technologies in concert—anaerobic membrane bioreactors (AnMBRs), clinoptilolite ion exchange, and GreenBox^TM ammonia electrolysis. The synergistic combination of these technologies will enable the first anaerobic treatment system that is capable of removing ammonia, a critical pollutant in municipal waste streams that is conventionally degraded using energy-intensive aeration processes. The component technologies are currently at an embryonic stage of development. Therefore, research efforts will initially focus on the optimization of each in the context of the FOB operating environment, followed by system integration and pilot-scale evaluation. AnMBR technology will be applied to degrade organics in wastewater and generate methane, which can be harvested for electrical and thermal energy. However, since AnMBRs do not remove ammonia and can also be hindered by its accumulation, clinoptilolite will be applied to sequester ammonia from the AnMBR reactor and effluent stream. Clinoptilolite is a naturally occurring ion exchanging zeolite that acts as a molecular sieve with high selectivity and capacity for ammonia. Upon saturation, clinoptilolite will be regenerated using sodium hydroxide brine solution, resulting in a highly concentrated ammonia brine waste. This waste stream is ideal for feeding the GreenBox^TM ammonia electrolysis system, which will be applied to convert ammonia into useful hydrogen fuel. Thus, the wastewater treatment system will generate two forms of useful fuel—methane and hydrogen—that can be easily converted into electrical and thermal energy at FOBs. It will also require minimal chemical inputs, reduce sludge production, be simple to operate, and be scalable. Treated water will be suitable for reuse applications.