title: Two-stage soil infiltration treatment system for treating ammonium wastewaters of low COD/TN ratios.
abstract: Soil infiltration treatment (SIT) is ineffective to treat ammonium wastewaters of total nitrogen (TN) > 100 mg l(-1). This study applied a novel two-stage SIT process for effective TN removal from wastewaters of TN>100 mg l(-1) and of chemical oxygen demand (COD)/TN ratio of 3.2-8.6. The wastewater was first fed into the soil column (stage 1) at hydraulic loading rate (HLR) of 0.06 m(3) m(-2) d(-1) for COD removal and total phosphorus (TP) immobilization. Then the effluent from stage 1 was fed individually into four soil columns (stage 2) at 0.02 m(3) m(-2) d(-1) of HLR with different proportions of raw wastewater as additional carbon source. Over the one-year field test, balanced nitrification and denitrification in the two-stage SIT revealed excellent TN removal (>90%) from the tested wastewaters.
authors.affiliation: Department of Environmental Science and Engineering, Fudan University, 220 Handan Road, Shanghai 200433, China.
authors.forename: Zhongfang
authors.initials: Z
authors.lastname: Lei
authors.forename: Ting
authors.initials: T
authors.lastname: Wu
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xiang
authors.initials: X
authors.lastname: Liu
authors.forename: Chunli
authors.initials: C
authors.lastname: Wan
authors.forename: Duu-Jong
authors.initials: DJ
authors.lastname: Lee
authors.forename: Joo-Hwa
authors.initials: JH
authors.lastname: Tay
mesh_terms: D000042:Absorption; D009584:Nitrogen / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry / Q000302:isolation & purification*; D012987:Soil / Q000737:chemistry*; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
chemical_list: D009584:Nitrogen; D010100:Oxygen; D000644:Quaternary Ammonium Compounds; D012987:Soil; D062065:Wastewater; D014874:Water Pollutants, Chemical