title: Influence of chemical oxygen demand concentrations on anaerobic ammonium oxidation by granular sludge from EGSB reactor.
abstract: OBJECTIVE
  To investigate the effect of chemical oxygen demand (COD) concentrations on the anaerobic ammonium oxidation (ANAMMOX).
  
  
  METHODS
  An Expanded Granular Sludge Bed (EGSB) reactor was used to cultivate the granular sludge and to perform the ANAMMOX reaction in the bench scale experiment. NH4(+)-N and NO2(-)-N were measured by using colorimetric method. NO3(-)-N was analyzed by using the UV spectrophotometric method. COD measurement was based on digestion with potassium dichromate in concentrated sulphuric acid.
  
  
  RESULTS
  When the COD concentrations in the reactors were 0 mg/L, 200 mg/L, 350 mg/L, and 550 mg/L, respectively, the NH4(+)-N removal efficiency was 12.5%, 14.2%, 14.3%, and 23.7%; the removal amount of NO2(-)-N was almost the same; the nitrate removal efficiency was 16.8%, 94.5%, 86.6%, and 84.2% and TN removal efficiency was 16.3%, 50.7%, 46.9%, and 50.4%, moreover, the COD removal efficiency was 85%, 65.7%, and 60%; the COD removal rate was 27.42, 61.88, and 97.8 mg COD/(h x L).
  
  
  CONCLUSIONS
  COD concentrations have a significant influence on anaerobic ammonium oxidation by granular sludge.
authors.affiliation: Laboratory of Environmental Technology, INET Tsinghua University, Beijing, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Kang
authors.forename: Jian-Long
authors.initials: JL
authors.lastname: Wang
mesh_terms: D000641:Ammonia / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D000693:Anaerobiosis; D019149:Bioreactors; D007218:Industrial Microbiology; D009584:Nitrogen / Q000302:isolation & purification / Q000378:metabolism; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry / Q000378:metabolism*; D011192:Potassium Dichromate / Q000737:chemistry; D012722:Sewage / Q000737:chemistry / Q000382:microbiology*; D013464:Sulfuric Acids / Q000737:chemistry; D013997:Time Factors; D014865:Waste Disposal, Fluid / Q000379:methods*
chemical_list: D012722:Sewage; D013464:Sulfuric Acids; D000641:Ammonia; D009584:Nitrogen; C033158:sulfuric acid; D010100:Oxygen; D011192:Potassium Dichromate