title: On-site evaluation of the performance of a full-scale down-flow hanging sponge reactor as a post-treatment process of an up-flow anaerobic sludge blanket reactor for treating sewage in India.
abstract: A down-flow hanging sponge (DHS) reactor is a novel, unaerated, aerobic, biofilm reactor that is used to polish effluent received from an up-flow anaerobic sludge blanket (UASB) reactor for treating municipal sewage. A full-scale DHS reactor was constructed for post-treatment of a full-scale UASB reactor at a municipal sewage treatment plant in India. Performance of the DHS reactor was evaluated with respect to organic removal over 1800 days of continuous operation. The UASB+DHS system consistently produced effluent with chemical oxygen demand (COD), biochemical oxygen demand (BOD), and suspended solids (SS) values of 37, 6.0 and 19 mg L(-1), on average, respectively. The sludge yield of the DHS reactor was estimated to be 0.04 kg SS kg(-1) COD removed or 0.12 kg SS kg(-1) BOD removed, which is considerably lower than other aerobic treatment methods that have been employed for polishing UASB effluent.
authors.affiliation: Department of Civil and Environmental Engineering, National Institute of Technology, Kisarazu College, 2-11-1 Kiyomidai-Higashi, Kisarazu, Chiba 292-0041, Japan. Electronic address: okubo@wangan.c.kisarazu.ac.jp.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Okubo
authors.affiliation: Center for Regional Environmental Research, National Institute for Environmental Studies (NIES), 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan. Electronic address: onodera.takashi@nies.go.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Onodera
authors.affiliation: Department of Civil and Environmental Engineering, National Institute of Technology, Kisarazu College, 2-11-1 Kiyomidai-Higashi, Kisarazu, Chiba 292-0041, Japan. Electronic address: uemura@wangan.c.kisarazu.ac.jp.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Uemura
authors.affiliation: Department of Environmental Systems Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata 940-2188, Japan. Electronic address: ecoya@vos.nagaokaut.ac.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamaguchi
authors.affiliation: Department of Social and Environmental Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi, Hiroshima 739-8527, Japan. Electronic address: ecoakiyo@hiroshima-u.ac.jp.
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Ohashi
authors.affiliation: New Industry Creation Hatchery Center, Tohoku University, 6-6-04 Aoba, Aramakiaza, 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: D000693:Anaerobiosis; D000818:Animals; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D007194:India; D011161:Porifera; D012722:Sewage; D014865:Waste Disposal, Fluid / Q000295:instrumentation* / Q000379:methods
chemical_list: D012722:Sewage
keywords: Developing countries; Down-flow hanging sponge (DHS); Municipal sewage treatment; Organic removal; Up-flow anaerobic sludge blanket (UASB)