title: Removal of high concentration ammonia from wastewater by a combination of partial nitrification and anammox treatment.
abstract: Attached growth reactors were developed separately for solids retention time (SRT)-controlled partial nitrification and for anaerobic ammonia oxidation (Anammox) treatment, and a new nitrogen removal process is proposed for wastewater containing highly concentrated ammonia. For partial nitrification, an attached growth medium of polyurethane foam was used. Partial nitrification was achieved stably under a SRT of 4 days, and the abundance ratio of NO2(-)-N to the sum of NH4(+)-N, NO2(-)-N and NO3(-)-N was approximately 0.8 after 10 days. Under a SRT of4 days, the amoA gene concentrations of ammonia-oxidizing bacteria increased from 1 x 10(8) to 7 x 10(8) copies/l, whereas the 16S ribosomal RNA (16S rRNA) gene concentrations of nitrite-oxidizing bacteria did not increase. These results indicate that SRT-controlled operation is a promising technology for achieving partial nitrification. For the Anammox treatment, an attached growth medium of non-woven fabric was used. Inorganic nitrogen removal of approximately 80-90% was observed at an inorganic nitrogen loading rate of over 10 kgN/(m3-medium.d) and an influent nitrogen concentration of 400 mgN/l. Our non-woven fabric reactor showed similar or superior Anammox performance to that reported previously. By using a combination of these two rectors, we can develop a method that combines partial nitrification and Anammox treatment for effective and stable nitrogen removal.
authors.affiliation: Department of Environmental Engineering, Kyoto University, Kyoto, Japan.
authors.forename: F
authors.initials: F
authors.lastname: Nishimura
authors.forename: T
authors.initials: T
authors.lastname: Hidaka
authors.forename: A
authors.initials: A
authors.lastname: Nakagawa
authors.forename: H
authors.initials: H
authors.lastname: Yorozu
authors.forename: H
authors.initials: H
authors.lastname: Tsuno
mesh_terms: D000641:Ammonia / Q000302:isolation & purification*; D001419:Bacteria / Q000235:genetics / Q000378:metabolism; D019149:Bioreactors / Q000382:microbiology; D004867:Equipment Design; D009566:Nitrates / Q000378:metabolism; D058465:Nitrification; D009584:Nitrogen; D011140:Polyurethanes; D012336:RNA, Ribosomal, 16S; D014865:Waste Disposal, Fluid / Q000295:instrumentation / Q000379:methods*
chemical_list: D009566:Nitrates; D011140:Polyurethanes; D012336:RNA, Ribosomal, 16S; D000641:Ammonia; D009584:Nitrogen