title: Enrichment of high activity nitrifers to enhance partial nitrification process.
abstract: Partial nitrification (PN) process is an essential pre-treatment to Anammox process for nitrogen removal from ammonium-rich wastewaters. High activity nitrifiers (HANs) are considered as the key to high-rate PN process. The HANs could be successfully enriched at free ammonia (FA) concentrations of 10-20 mg NH(3)-NL(-1), which differed significantly from those enriched at FA concentrations of 1-3 mg NH(3)-NL(-1). The maximum specific ammonium conversion rate, half saturation constant, half inhibition constant, cell yield and decay rate were 2.87 g N g(-1) VSS d(-1), 5.82 mg N L(-1), 8218.8 mg N L(-1), 0.15 g VSS g(-1) NH(4)(+)-N and 0.09 d(-1) for HANs at 30 degrees C, respectively, which endowed the PN process a volumetric conversion rate (VCR) as high as 2.22+/-0.33 kg N m(-3) d(-1). The cultivation mode of HANs was workable and the HANs were promising as inoculum for the PN process.
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou, China.
authors.forename: Jianwei
authors.initials: J
authors.lastname: Chen
authors.forename: Ping
authors.initials: P
authors.lastname: Zheng
authors.forename: Yi
authors.initials: Y
authors.lastname: Yu
authors.forename: Qaisar
authors.initials: Q
authors.lastname: Mahmood
authors.forename: Chongjian
authors.initials: C
authors.lastname: Tang
mesh_terms: D001419:Bacteria / Q000254:growth & development / Q000378:metabolism*; D001673:Biodegradation, Environmental; D001681:Biological Assay; D019149:Bioreactors / Q000382:microbiology; D052918:Environmental Restoration and Remediation / Q000379:methods*; D007700:Kinetics; D009566:Nitrates / Q000302:isolation & purification*; D010084:Oxidation-Reduction; D000644:Quaternary Ammonium Compounds / Q000378:metabolism; D012722:Sewage / Q000382:microbiology
chemical_list: D009566:Nitrates; D000644:Quaternary Ammonium Compounds; D012722:Sewage