title: Autotrophic nitrogen removal over nitrite in a sponge-bed trickling filter.
abstract: Partial nitritation in sponge-bed trickling filters (STF) under natural air circulation was studied in two reactors: STF-1 and STF-2 operated at 30°C with sponge thickness of 0.75 and 1.50cm, respectively. The coexistence of nitrifiers and Anammox bacteria was obtained and attributed to the favorable environment created by the reactors' design and operational regimes. After 114days of operation, the STF-1 had an average NH4(+)-N removal of 69.3% (1.17kgN/m(3)sponged) and a total nitrogen removal of 52.2% (0.88kgN/m(3)sponged) at a Nitrogen Loading Rate (NLR) of 1.68kgN/m(3)sponged and Hydraulic Retention Time (HRT) of 1.71h. The STF-2 showed an average NH4(+)-N removal of 81.6 % (0.77kgN/m(3)sponged) and a total nitrogen removal of 54% (0.51kgN/m(3)sponged), at an NLR of 0.95kgN/m(3)sponged and HRT of 2.96h. The findings suggest that autotrophic nitrogen removal over nitrite in STF systems is a feasible alternative.
authors: Environmental Engineering and Water Technology Department, UNESCO-IHE, PO Box 3015, 2601 DA Delft, The Netherlands; Faculty of Civil Engineering and Geosciences, Department of Water Management, Delft University of Technology, PO Box 5048, 2600 GA Delft, The Netherlands. Electronic address: j.sanchezguillen@unesco-ihe.org.
authors: J A
authors: JA
authors: Sánchez Guillén
authors: Environmental Engineering and Water Technology Department, UNESCO-IHE, PO Box 3015, 2601 DA Delft, The Netherlands. Electronic address: lkmcbj@yahoo.co.uk.
authors: L K M C B
authors: LKMCB
authors: Jayawardana
authors: Environmental Engineering and Water Technology Department, UNESCO-IHE, PO Box 3015, 2601 DA Delft, The Netherlands. Electronic address: c.lopezvazquez@unesco-ihe.org.
authors: C M
authors: CM
authors: Lopez Vazquez
authors: Environmental Engineering and Water Technology Department, UNESCO-IHE, PO Box 3015, 2601 DA Delft, The Netherlands. Electronic address: deoli2@unesco-ihe.org.
authors: L M
authors: LM
authors: de Oliveira Cruz
authors: Environmental Engineering and Water Technology Department, UNESCO-IHE, PO Box 3015, 2601 DA Delft, The Netherlands; Faculty of Applied Sciences, Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands. Electronic address: d.brdjanovic@unesco-ihe.org.
authors: D
authors: D
authors: Brdjanovic
authors: Environmental Engineering and Water Technology Department, UNESCO-IHE, PO Box 3015, 2601 DA Delft, The Netherlands; Faculty of Civil Engineering and Geosciences, Department of Water Management, Delft University of Technology, PO Box 5048, 2600 GA Delft, The Netherlands. Electronic address: j.vanlier@unesco-ihe.org.
authors: J B
authors: JB
authors: van Lier
mesh_terms: D052818:Autotrophic Processes / Q000502:physiology; D001421:Bacteria, Anaerobic / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D009584:Nitrogen / Q000302:isolation & purification / Q000378:metabolism*; D014462:Ultrafiltration / Q000295:instrumentation*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification / Q000378:metabolism*; D018508:Water Purification / Q000295:instrumentation*
chemical_list: D014874:Water Pollutants, Chemical; D009584:Nitrogen
keywords: Anammox; DHS; Partial nitritation; Sponge-bed trickling filter; UASB