title: Development of a new non-aeration-based sewage treatment technology: Performance evaluation of a full-scale down-flow hanging sponge reactor employing third-generation sponge carriers.
abstract: A practical-scale down-flow hanging sponge (DHS) reactor using third-generation (G3) sponge carriers was applied for treatment of the effluent from an up-flow anaerobic sludge blanket (UASB) reactor treating municipal sewage. The process performance of the DHS reactor filled with G3 sponge carriers (DHS-G3) was evaluated by conducting an on-site experiment in India over one year. The performance of the DHS-G3 for removal of organic matter and ammonium-nitrogen at a relatively short hydraulic retention time (HRT) of only 0.66 h satisfied the Indian effluent quality standards except for fecal coliform. The removal rate constants for total biochemical oxygen demand (BOD) and fecal coliform determined based on the water quality profiles along the DHS-G3 almost reached equilibrium approximately four months after the start of operation, i.e., 2.45 h(-1) for BOD and 2.30 h(-1) for fecal coliform, respectively. The oxygen utilization activity of retained sludge was determined to assess the distribution of heterotrophic and autotrophic bacteria along the DHS-G3. Nitrification was promoted in the lower portion of the DHS-G3 reactor in the duration with low organic load, while it decreased when the organic load was increased, probably due to proliferation of heterotrophic bacteria.
authors.affiliation: Dept. of Civil Engineering, National Institute of Technology, Kisarazu College, 2-11-1 Kiyomidaihigashi, Kisarazu, Chiba, 292-0041, Japan. Electronic address: okubo@wangan.c.kisarazu.ac.jp.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Okubo
authors.affiliation: Dept. of Civil and Environmental Engineering, Tohoku University, 6-6-06 Aza-Aoba, Aramaki, Aoba-ku, Sendai, Miyagi, 980-8579, Japan. Electronic address: kengo.kubota.a7@tohoku.ac.jp.
authors.forename: Kengo
authors.initials: K
authors.lastname: Kubota
authors.affiliation: Dept. of Civil and Environmental Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, 940-2188, Japan. Electronic address: ecoya@vos.nagaoka.ac.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamaguchi
authors.affiliation: Dept. of Civil Engineering, National Institute of Technology, Kisarazu College, 2-11-1 Kiyomidaihigashi, Kisarazu, Chiba, 292-0041, Japan. Electronic address: uemura@wangan.c.kisarazu.ac.jp.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Uemura
authors.affiliation: New Industry Creation Hatchery Center, Tohoku University, 6-6-04 Aza-Aoba, Aramaki, Aoba-ku, Sendai, Miyagi, 980-8579, Japan. Electronic address: hideki.harada.e3@tohoku.ac.jp.
authors.forename: Hideki
authors.initials: H
authors.lastname: Harada
mesh_terms: D000818:Animals; D019149:Bioreactors / Q000382:microbiology*; D058465:Nitrification; D009584:Nitrogen; D012722:Sewage / Q000382:microbiology*; D014865:Waste Disposal, Fluid; D018508:Water Purification
chemical_list: D012722:Sewage; D009584:Nitrogen
keywords: Down-flow hanging sponge reactor; Municipal sewage treatment; Oxygen utilization rate; Sponge carrier; Up-flow anaerobic sludge blanket reactor