title: Denitrification of nitrate contaminated groundwater with a fiber-based biofilm reactor.
abstract: A fiber-based biofilm reactor was developed using a laboratory-scale apparatus for treatment of nitrate-contaminated groundwater. Denitrification bacteria were inoculated by anaerobic sludge from a wastewater treatment plant. Nitrate removal efficiency, nitrite accumulation, COD and pH in the treated water were investigated under various conditions set by several parameters including hydraulic retention times (HRTs) (24, 20, 16, 12, 8, 4 and 2h), influent nitrate loading (around 50, 100 and 150 NO(3)(-)-N mg L(-1)), pH (5, 6, 7, 8, and 9) and ratios of carbon to nitrogen (C/N=3.00, 2.00, 1.50 1.25 and 1.00). The experimental results demonstrated that the optimum reaction parameters were pH 7-7.5,C/N=1.25 and HRT=8h, under which over 99% of NO(3)(-)-N was removed, almost no NO(2)(-)-N accumulated and COD was nearly zero in treated water when the concentration of NO(3)(-)-N was around 100.00 mg L(-1) in influent.
authors.affiliation: Water Resource and Environmental Engineering, China University of Geosciences, Beijing, China.
authors.forename: Qinghong
authors.initials: Q
authors.lastname: Wang
authors.forename: Chuanping
authors.initials: C
authors.lastname: Feng
authors.forename: Yingxin
authors.initials: Y
authors.lastname: Zhao
authors.forename: Chunbo
authors.initials: C
authors.lastname: Hao
mesh_terms: D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D018441:Biofilms; D019149:Bioreactors; D002244:Carbon; D006863:Hydrogen-Ion Concentration; D009566:Nitrates / Q000302:isolation & purification*; D009584:Nitrogen; D010100:Oxygen / Q000032:analysis; D012987:Soil; D013997:Time Factors; D014865:Waste Disposal, Fluid; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D014881:Water Supply
chemical_list: D009566:Nitrates; D012987:Soil; D014874:Water Pollutants, Chemical; D002244:Carbon; D009584:Nitrogen; D010100:Oxygen