title: Struvite precipitation for ammonia nitrogen removal in 7-aminocephalosporanic acid wastewater.
abstract: 7-Aminocephalosporanic acid wastewater usually contains high concentrations of ammonium (NH₄⁺-N), which is known to inhibit nitrification during biological treatment processes. Chemical precipitation is a useful technology to remove ammonium from wastewater. In this paper, the removal of ammonium from 7-aminocephalosporanic acid wastewater was studied. The optimum pH, molar ratio, and various chemical compositions of magnesium ammonium phosphate (MAP) precipitation were investigated. The results indicated that ammonium in 7-aminocephalosporanic acid wastewater could be removed at an optimum pH of 9. The Mg²⁺:NH₄⁺-N:PO₄ ³⁻-P molar ratio was readily controlled at a ratio of 1:1:1.1 to both effectively remove ammonium and avoid creating a higher concentration of PO₄ ³⁻-P in the effluent. MgCl₂·6H₂O + 85% H₃PO₄ was the most efficient combination for NH₄⁺-N removal. Furthermore, the lowest concentration of the residual PO₄ ³⁻-P was obtained with the same combination. Struvite precipitation could be considered an effective technology for the NH₄⁺-N removal from the 7-aminocephalosporanic acid wastewater.
authors.affiliation: School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China.
authors.forename: Zaixing
authors.initials: Z
authors.lastname: Li
authors.forename: Xuguang
authors.initials: X
authors.lastname: Ren
authors.forename: Jiane
authors.initials: J
authors.lastname: Zuo
authors.forename: Yanfang
authors.initials: Y
authors.lastname: Liu
authors.forename: Erhong
authors.initials: E
authors.lastname: Duan
authors.forename: Jingliang
authors.initials: J
authors.lastname: Yang
authors.forename: Ping
authors.initials: P
authors.lastname: Chen
authors.forename: Yongjun
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000641:Ammonia / Q000737:chemistry*; D002511:Cephalosporins / Q000737:chemistry*; D011232:Chemical Precipitation; D006863:Hydrogen-Ion Concentration; D017616:Magnesium Compounds / Q000737:chemistry*; D009584:Nitrogen / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry*; D000069877:Struvite; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D002511:Cephalosporins; D017616:Magnesium Compounds; D010710:Phosphates; D014874:Water Pollutants, Chemical; D000641:Ammonia; C030735:7-aminocephalosporanic acid; D000069877:Struvite; D009584:Nitrogen