title: Performance of magnesium ammonium phosphate precipitation and its effect on biological treatability of leather tanning industry wastewaters.
abstract: Leather tanning industry is one of the several industries discharging significant amount of nitrogen. Magnesium ammonium phosphate (MAP) precipitation is a promising pretreatment for leather tanning industry wastewaters for the control of toxic parameters; excess suspended solids as well as nitrogen which increase the cost and complexity of following biological treatment. Application of MAP precipitation, however, modifies the characteristics and biological treatability of wastewaters. In this study, characteristics and biological treatability of MAP precipitation effluent were experimentally investigated using the wastewaters obtained from a bovine leather processing plant. An experimental study involving the determination of COD fractions and kinetic parameters of biological treatment was conducted for both gravity settling and MAP precipitation. Results of the study indicated that MAP precipitation, in addition to high degree of nitrogen removal, yielded a soluble, readily biodegradable effluent which was also free from toxics. MAP precipitation provided an effluent COD of almost half of that of gravity settling. Reduced value of soluble residual microbial products (Sp) obtained with MAP precipitation effluent was an additional benefit.
authors.affiliation: Environmental Engineering Department, Civil Engineering Faculty, Istanbul Technical University, Maslak, Istanbul, Turkey. otunay@ins.itu.edu.tr
authors.forename: Olcay
authors.initials: O
authors.lastname: Tünay
authors.forename: Gülsüm Emel
authors.initials: GE
authors.lastname: Zengin
authors.forename: Işik
authors.initials: I
authors.lastname: Kabdaşli
authors.forename: Ozlem
authors.initials: O
authors.lastname: Karahan
mesh_terms: D000818:Animals; D001673:Biodegradation, Environmental; D002417:Cattle; D011232:Chemical Precipitation; D006490:Hemostatics / Q000737:chemistry*; D007700:Kinetics; D017616:Magnesium Compounds / Q000737:chemistry*; D009584:Nitrogen / Q000302:isolation & purification*; D010710:Phosphates / Q000737:chemistry*; D012867:Skin; D012995:Solubility; D000069877:Struvite; D013783:Textile Industry; D014865:Waste Disposal, Fluid / Q000379:methods*; D018508:Water Purification / Q000379:methods*
chemical_list: D006490:Hemostatics; D017616:Magnesium Compounds; D010710:Phosphates; D000069877:Struvite; D009584:Nitrogen