title: Characteristics of DO, organic matter, and ammonium profile for practical-scale DHS reactor under various organic load and temperature conditions.
abstract: Profile analysis of the down-flow hanging sponge (DHS) reactor was conducted under various temperature and organic load conditions to understand the organic removal and nitrification process for sewage treatment. Under high organic load conditions (3.21-7.89 kg-COD m-3day-1), dissolved oxygen (DO) on the upper layer of the reactor was affected by organic matter concentration and water temperature, and sometimes reaches around zero. Almost half of the CODCrwas removed by the first layer, which could be attributed to the adsorption of organic matter on sponge media. After the first layer, organic removal proceeded along the first-order reaction equation from the second to the fourth layers. The ammoniacal nitrogen removal ratio decreased under high organic matter concentration (above 100 mg L-1) and low DO (less than 1 mg L-1) condition. Ammoniacal nitrogen removal proceeded via a zero-order reaction equation along the reactor height. In addition, the profile results of DO, CODCr, and NH3-N were different in the horizontal direction. Thus, it is thought the concentration of these items and microbial activities were not in a uniform state even in the same sponge layer of the DHS reactor.
authors.affiliation: a Department of Energy and Environment Science , Nagaoka University of Technology , Niigata , Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Nomoto
authors.affiliation: b New Industry Creation Hatchery Center , Tohoku University , Sendai , Japan.
authors.forename: Muntjeer
authors.initials: M
authors.lastname: Ali
authors.affiliation: c Department of Civil Engineering , Indian Institute of Technology Roorkee , Roorkee , India.
authors.forename: Komal
authors.initials: K
authors.lastname: Jayaswal
authors.affiliation: d Faculty of Applied Life Sciences , Niigata University of Pharmacy and Applied Life Sciences , Niigata , Japan.
authors.forename: Akinori
authors.initials: A
authors.lastname: Iguchi
authors.affiliation: e Department of Civil and Environmental Engineering , Nagaoka University of Technology , Niigata , Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Hatamoto
authors.affiliation: f Department of Civil Engineering , National Institute of Technology, Kisarazu College , Kisarazu , Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Okubo
authors.affiliation: b New Industry Creation Hatchery Center , Tohoku University , Sendai , Japan.
authors.forename: Masanobu
authors.initials: M
authors.lastname: Takahashi
authors.affiliation: g Department of Civil and Environmental Engineering , Tohoku University , Sendai , Japan.
authors.forename: Kengo
authors.initials: K
authors.lastname: Kubota
authors.affiliation: h Department of Civil Engineering , National Institute of Technology, Kagawa College , Takamatsu , Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Tagawa
authors.affiliation: f Department of Civil Engineering , National Institute of Technology, Kisarazu College , Kisarazu , Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Uemura
authors.affiliation: i Department of Science of Technology Innovation , Nagaoka University of Technology , Niigata , Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamaguchi
authors.affiliation: b New Industry Creation Hatchery Center , Tohoku University , Sendai , Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Harada
mesh_terms: D064751:Ammonium Compounds / Q000032:analysis*; D019149:Bioreactors; D009584:Nitrogen; D010100:Oxygen / Q000032:analysis*; D012722:Sewage; D013696:Temperature; D014865:Waste Disposal, Fluid
chemical_list: D064751:Ammonium Compounds; D012722:Sewage; D009584:Nitrogen; D010100:Oxygen
keywords: Down-flow hanging sponge; developing country; high organic load; nitrification; sewage treatment