title: Ammonium recovery from reject water combined with hydrogen production in a bioelectrochemical reactor.
abstract: In this study, a bioelectrochemical reactor was investigated for simultaneous hydrogen production and ammonium recovery from reject water, which is an ammonium-rich side-stream produced from sludge treatment processes at wastewater treatment plants. In the anode chamber of the reactor, microorganisms converted organic material into electrical current. The electrical current was used to generate hydrogen gas at the cathode with 96±6% efficiency. Real or synthetic reject water was fed to the cathode chamber where proton reduction into hydrogen gas resulted in a pH increase which led to ammonium being converted into volatile ammonia. The ammonia could be stripped from the solution and recovered in acid. Overall, ammonium recovery efficiencies reached 94% with synthetic reject water and 79% with real reject water. This process could potentially be used to make wastewater treatment plants more resource-efficient and further research is warranted.
authors: Division of Water Environment Technology, Civil and Environmental Engineering, Chalmers University of Technology, SE-41296 Gothenburg, Sweden. Electronic address: sherrywu7@hotmail.com.
authors: Xue
authors: X
authors: Wu
authors: Division of Water Environment Technology, Civil and Environmental Engineering, Chalmers University of Technology, SE-41296 Gothenburg, Sweden. Electronic address: oskar.modin@chalmers.se.
authors: Oskar
authors: O
authors: Modin
mesh_terms: D000641:Ammonia / Q000737:chemistry; D064751:Ammonium Compounds / Q000737:chemistry*; D001674:Bioelectric Energy Sources; D019149:Bioreactors; D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D004572:Electrolysis; D005740:Gases; D006859:Hydrogen / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D009584:Nitrogen / Q000737:chemistry; D012722:Sewage; D014865:Waste Disposal, Fluid / Q000379:methods; D062065:Wastewater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification / Q000379:methods*
chemical_list: D000641:Ammonia; D064751:Ammonium Compounds; D005740:Gases; D006859:Hydrogen; D009584:Nitrogen; D012722:Sewage; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Anaerobic digester centrate; Microbial electrolysis cell; Nitrogen recovery; Sludge liquor