The GreenBox: Wastewater Remediation and Energy Generation

G.G. Botte
Ohio University - Center for Electrochemical Engineering Research,
United States

Keywords: ammonia oxidation, nitrate removal, water remediation, water-energy nexus, clean water, clean energy

Summary:

Currently, wastewater treatment solutions for ammonia (biological and chemical treatments) consume a significant amount of energy, have high operational costs, require significant capital investment, are not easily adaptable to tighter emissions regulations and are large in size. In addition, current methods do not scale-down well for non-point source pollution, which usually comes from rural areas such as livestock facilities and fertilizer run-off leading to algae bloom. For this reason, the EPA has limited the nitrate contamination level in drinking water to 10 mg/l and the algae bloom problem has caused the EPA to consider reducing this limit to a lower value. Ohio University’s patented ammonia electrolysis is the only technology that allows the direct conversion of ammonia into benign pure nitrogen gas and pure fuel grade hydrogen gas. The process, also known as the “Ammonia GreenBox” is compact, consumes less energy, reduces capital and operational costs and is amenable to regulatory changes via process control. Finally, the GreenBox provides an opportunity to generate hydrogen for use within the wastewater treatment plant infrastructure. As megatrends in population growth and urbanization continue to increase, the GreenBox provides the opportunity to retrofit and improve on current remediation plants, while also aiding in the next generation of plants that can handle more waste output from municipalities. Specifically, the Greenbox compares favorably to current technologies by reducing capital costs ($ per million gallons per day) by 54%, reducing operational costs ($ per pound of ammonia) by 92%, improving on regulatory limits (mg of nitrate per liter) by 90% and improving energy efficiency (kilowatt hour per kilogram of ammonia removed) by 85%.