title: [Mechanism of nitrogen removal by partial nitrification-denitrification biological filter].
abstract: The controlling factors for nitrite accumulation in partial nitrification and mechanism of nitrogen removal from the secondary effluent of wastewater treatment plant by partial nitrification-denitrification biological filter were investigated. The results showed that nitrite accumulated with increasing of pH value in the influent under the condition of temperature was (30 +/- 1) degrees C. The nitrite accumulation achieved to the highest at a pH value of 8.5 in this batch experiments. In addition, the nitrite accumulation presented increasing tendency through the up-flow nitrifying biological filter, which can be adjusted by the changes of pH and DO through the filter. The removal efficiency of NH4+ -N was over 90% by the partial nitrification-denitrification biological filter. Meanwhile, carbon sources were supplied for the denitrifying bacteria to accomplish denitrification process. Under the condition of COD/TN at a value of 3.0, the concentration of TN in the effluent of denitrifying biofilter was 8-9 mg x L(-1) and the removal efficiency achieved 79% - 81%, stably.
authors.affiliation: Department of Environmental Science and Engineering, School of Food and Chemical Engineering, Beijing Technology and Business University, Beijing 100048, China. syingxue@126.com
authors.forename: Ying-Xue
authors.initials: YX
authors.lastname: Sun
authors.forename: Dong
authors.initials: D
authors.lastname: Xu
authors.forename: Yuan
authors.initials: Y
authors.lastname: Tian
authors.forename: Yan-Fei
authors.initials: YF
authors.lastname: Li
mesh_terms: D064751:Ammonium Compounds / Q000302:isolation & purification / Q000378:metabolism; D018441:Biofilms; D019149:Bioreactors / Q000382:microbiology; D058440:Denitrification; D005374:Filtration; D058465:Nitrification; D009573:Nitrites / Q000302:isolation & purification* / Q000378:metabolism; D009584:Nitrogen / Q000302:isolation & purification* / Q000378:metabolism; D014865:Waste Disposal, Fluid / Q000379:methods*; D018508:Water Purification
chemical_list: D064751:Ammonium Compounds; D009573:Nitrites; D009584:Nitrogen