| Title: | Performance of calcium peroxide for removal of endocrine-disrupting compounds in waste activated sludge and promotion of sludge solubilization |
| Address: | "State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China. State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China. Electronic address: liyongmei@tongji.edu.cn" |
| DOI: | 10.1016/j.watres.2015.01.005 |
| ISSN/ISBN: | 1879-2448 (Electronic) 0043-1354 (Linking) |
| Abstract: | "Removal of six phenolic endocrine disrupting compounds (EDCs) (estrone, 17beta-estradiol, 17alpha-ethinylestradiol, estriol, bisphenol A, and 4-nonylphenols) from waste activated sludge (WAS) was investigated using calcium peroxide (CaO2) oxidation. Effects of initial pH and CaO2 dosage were investigated. The impacts of CaO2 treatment on sludge solubilization and anaerobic digestion were also evaluated. Specifically, the role of reactive oxygen species (ROS) in EDC degradation during CaO2 oxidation was tested. Effects of 6 metal ions contained in the sludge matrix on EDC degradation were also evaluated. The results showed that CaO2 treatment can be a promising technology for EDC removal and facilitating sludge reuse. The EDC removal efficiencies increased with the increase in CaO2 dosage. At CaO2 doses of more than 0.34 g per gram of total solid (g g(-1) TS), more than 50% of EDCs were removed in a wide pH range of 2-12. Higher removal efficiencies were achieved at initial pH values of 12 and 2. The products of EDCs during CaO2 oxidation had less estrogenic activity than the originals. Under the conditions of neutral pH and CaO2 dosage = 0.34 g g(-1) TS, the sludge solubilization can be improved by increasing the soluble total organic carbon (STOC) and volatile suspended solids (VSS) reduction by 25% and 27% in 7 d, respectively; the volatile fatty acid (VFA) production was enhanced by 96% in the 15 d following anaerobic digestion. The ROS released by CaO2 are the main factors contributing to EDC removal, among which, hydroxyl radicals (OH) play the most important role. Metal ions contained in the sludge matrix also affected EDC removal. For most cases, Fe, Cu, and Zn had positive effects; Mn and Ag had negative effects; and Mg had an insignificant effect on EDC removal" |
| Keywords: | Benzhydryl Compounds/chemistry Endocrine Disruptors/*chemistry Estradiol/chemistry Estriol/analysis/chemistry Estrone/chemistry Ethinyl Estradiol/chemistry Hydrogen-Ion Concentration Oxidation-Reduction Peroxides/*chemistry Phenols/chemistry Reactive Oxyg; |
| Notes: | "MedlineZhang, Ai Wang, Jie Li, Yongmei eng Research Support, Non-U.S. Gov't England 2015/01/24 Water Res. 2015 Mar 15; 71:125-39. doi: 10.1016/j.watres.2015.01.005. Epub 2015 Jan 12" |
