title: Degradation of endocrine-disrupting chemicals during activated sludge reduction by ozone.
abstract: Ozonation has been considered to be an effective means for the reduction of excess sludge in recent years. However, it remains largely unknown whether hydrophobic organic micro-pollutants, which are originally adsorbed on activated sludge, will be released into wastewater upon ozonation because of sludge solubilization. This study investigated the degradation efficiencies of several typical endocrine-disrupting chemicals (EDCs) during sludge ozonation, including estrone (E1), estriol (E3), 17α-ethynylestradiol (EE2), bisphenol A (BPA), and 4-nonylphenol (NP). Results indicate that the EDCs present in activated sludge could be effectively removed by O3 even though the apparent rate constants in sludge were 3-4 orders of magnitude lower than those in water. However, the applied O3 dose should be prudently controlled because a low dose (e.g., 29mgO3g(-1)SS) may lead to an increase of BPA and NP concentrations in the liquid phase of activated sludge. Furthermore, H2O2 addition or pH adjustment could improve the removal of most studied EDCs, but exert a negative effect on the more hydrophobic and refractory compound, NP.
authors.affiliation: State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuang-qing Road, Beijing 100085, China. qiangz@rcees.ac.cn
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Qiang
authors.forename: Yafeng
authors.initials: Y
authors.lastname: Nie
authors.forename: Weiwei
authors.initials: W
authors.lastname: Ben
authors.forename: Jiuhui
authors.initials: J
authors.lastname: Qu
authors.forename: Heqing
authors.initials: H
authors.lastname: Zhang
mesh_terms: D001559:Benzhydryl Compounds / Q000032:analysis / Q000737:chemistry; D052244:Endocrine Disruptors / Q000032:analysis* / Q000737:chemistry; D004964:Estriol; D004970:Estrone / Q000032:analysis / Q000737:chemistry; D004997:Ethinyl Estradiol / Q000032:analysis / Q000737:chemistry; D010126:Ozone / Q000737:chemistry*; D010636:Phenols / Q000032:analysis / Q000737:chemistry; D012722:Sewage / Q000737:chemistry* / Q000382:microbiology; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D052244:Endocrine Disruptors; D004964:Estriol; D004970:Estrone; D004997:Ethinyl Estradiol; D010126:Ozone; D010636:Phenols; D012722:Sewage; D014874:Water Pollutants, Chemical; C041594:4-nonylphenol; C006780:bisphenol A; D000098826:Bisphenol A Compounds