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.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.biortech.2015.07.015 | DOI Listing |
Sci Total Environ
December 2024
Department of Civil and Environmental Engineering, Nagaoka University of Technology, Nagaoka 940-2188, Japan; Department of Science of Technology Innovation, Nagaoka University of Technology, Nagaoka 940-2188, Japan. Electronic address:
Providing anaerobic environments can enhance the denitrification capacity of wastewater treatment systems. This study developed an aerobic-anaerobic downflow hanging sponge (DHS) reactor to increase denitrification. A siphon tube was integrated with a conventional DHS to create anaerobic conditions by controlling a water column inside the reactor.
View Article and Find Full Text PDFBioresour Technol
December 2024
Department of Science of Technology Innovation, Nagaoka University of Technology, Nagaoka, 940-2188, Japan; Department of Civil and Environmental Engineering, Nagaoka University of Technology, Nagaoka, 940-2188, Japan. Electronic address:
This study presents a novel approach to sustainable aquaculture by integrating biofloc technology (BFT) with a compact down-flow hanging sponge (DHS) reactor. The integrated BFT-DHS system effectively removed nitrogen compounds while maintaining ammonia-nitrogen (NH-N) concentrations below 1 mg-N L without water exchange. Application of this system in a tank bred with juvenile Oreochromis niloticus showed a high NH-N removal rate of up to 97 % and nitrite (NO -N) concentrations were maintained at 0.
View Article and Find Full Text PDFJ Environ Sci Health A Tox Hazard Subst Environ Eng
September 2024
Department of Science of Technology Innovation, Nagaoka University of Technology, Nagaoka, Japan.
Aquaponics is a promising solution for addressing food security concerns. Nonetheless, an effective water-purification system is necessary to achieve high and stable yields of fish and vegetables. This study aimed to evaluate the nitrification and oxygen transfer performance of a laboratory-scale down-flow hanging sponge (DHS) reactor with aquaponics system to treat water in an closed-aquaculture system.
View Article and Find Full Text PDFEcotoxicol Environ Saf
September 2024
Department of Civil and Environmental Engineering, Nagaoka University of Technology, Nagaoka, Niigata, 940-2188 Japan; Department of Science and Technology Innovation, Nagaoka University of Technology, Nagaoka, Niigata 940-2188, Japan.
In recirculating aquaculture systems (RAS), maintaining water quality in aquaculture tanks is a paramount factor for effective fish production. A down-flow hanging sponge (DHS) reactor, a trickling filter system used for water treatment of RAS that employs sponges to retain biomass, has high nitrification activity. However, nitrification in seawater RAS requires a long start-up time owing to the high salinity stress.
View Article and Find Full Text PDFJ Environ Sci Health A Tox Hazard Subst Environ Eng
August 2024
Regional Environment Conservation Division, National Institute for Environmental Studies, Tsukuba, Japan.
Down-flow hanging sponge (DHS) reactors, employed in domestic wastewater treatment, have demonstrated efficacy in eliminating and other potentially pathogenic bacteria. The aim of this study was to elucidate the mechanism of removal of by employing a cube-shaped polyurethane sponge carrier within a compact hanging reactor. An removal experiment was conducted on this prepared sponge.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!