title: Relaxing the formation of hypoxic bottom water with sediment microbial fuel cells.
abstract: The method of improving bottom water environment using industrial wastes to suppress diffusion substances from bottom sediment has recently captured the attention of many researchers. In this study, wastewater discharge-derived sediment was used to examine an alternative approach involving the use of sediment microbial fuel cells (SMFCs) in relaxing the formation of hypoxic bottom water, and removing reduced substances from sediment. Concentrations of dissolved oxygen (DO) and other ions were measured in overlying water and sediment pore water with and without the application of SMFCs. The results suggest that SMFCs can markedly reduce hydrogen sulfide and manganese ion concentrations in overlying water, and decrease the depletions of redox potential and DO concentration. In addition, SMFCs can dissolve ferric compounds in the sediment and thereby release the ferric ion available to fix phosphate in the sediment. Our results indicate that SMFCs can be used as an alternative method to relax the formation of hypoxic bottom water and to remove reduced substances from the sediment, thus improving the quality of both water and sediment environments.
authors.affiliation: a Department of Civil and Environmental Engineering , Hiroshima University , Higashihiroshima City , Hiroshima-Ken , Japan.
authors.forename: Narong
authors.identifier: http://orcid.org/0000-0001-7881-7000
authors.initials: N
authors.lastname: Touch
authors.affiliation: a Department of Civil and Environmental Engineering , Hiroshima University , Higashihiroshima City , Hiroshima-Ken , Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Hibino
authors.affiliation: a Department of Civil and Environmental Engineering , Hiroshima University , Higashihiroshima City , Hiroshima-Ken , Japan.
authors.forename: Yuki
authors.identifier: http://orcid.org/0000-0003-1493-1212
authors.initials: Y
authors.lastname: Morimoto
authors.affiliation: a Department of Civil and Environmental Engineering , Hiroshima University , Higashihiroshima City , Hiroshima-Ken , Japan.
authors.forename: Nobutaka
authors.identifier: http://orcid.org/0000-0001-6510-6197
authors.initials: N
authors.lastname: Kinjo
mesh_terms: D000693:Anaerobiosis; D001674:Bioelectric Energy Sources; D004058:Diffusion; D019015:Geologic Sediments / Q000032:analysis*; D010100:Oxygen; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000032:analysis*
chemical_list: D010100:Oxygen; D062065:Wastewater
keywords: SMFC; dissolved oxygen; hydrogen sulfide; hypoxic bottom water; phosphate fixation