State Key Laboratory of Hydrology-Water Resources & Hydraulic Engineering, Nanjing Hydraulic Research Institute, Nanjing, 210098, China; Center for Eco-Environment Research, Nanjing Hydraulic Research Institute, Nanjing, 210098, China.
State Key Laboratory of Hydrology-Water Resources & Hydraulic Engineering, Nanjing Hydraulic Research Institute, Nanjing, 210098, China; Yangtze Institute for Conservation and Green Development, Nanjing, 210098, China; Center for Eco-Environment Research, Nanjing Hydraulic Research Institute, Nanjing, 210098, China.
Chemosphere. 2021 Dec;285:131515. doi: 10.1016/j.chemosphere.2021.131515. Epub 2021 Jul 10.
In this study, we have investigated the purification efficiency during enhanced coagulation, ozone oxidation and their combined processes for the removal of trace amounts of EDCs in different DOM matrices. The results indicated that the maximum removal efficiency of EDCs occurred at or near pH 7.0 when measured over a pH range of 4.0-10.0. The addition of natural colloids had a two-part influence. While the floc generated by polyaluminium chloride (PAC) significantly increased in size from 198.0 μm to 290.4 μm with a simultaneous improvement in the removal efficiency of EDCs, the floc size generated by polyferric sulfate (PFS) had no worthwhile change except for a slight decrement. The removal efficiency of EDCs and the decrease in spectral parameters including UVA254, UVA280 and humic-like fluorescence during ozonation processes with and without pre-coagulation were investigated. During the ozonation process, efficient elimination of target EDCs are achieved at low O doses (O/dissolved organic carbon (DOC) < 0.2) in different water matrices. The pH-titration differential absorbance spectra technique further demonstrated that the high reactivity of O to EDCs is owing to their phenolic moieties. In addition, when mgO/mgDOC ratio reaches to ~0.40, >90% of estrogenic activity was eliminated. In a nutshell, ozonation with pre-coagulation together leads to considerably higher abatement of EDCs and estradiol (E2) equivalent values (EEQ) at the same ozone dosage than ozonation only process for wastewater treatment.
在这项研究中，我们研究了强化混凝、臭氧氧化及其组合工艺在去除不同 DOM 基质中痕量 EDCs 时的净化效率。结果表明，当 pH 值在 4.0-10.0 之间测量时，EDCs 的最大去除效率发生在 pH 值为 7.0 左右。天然胶体的添加有两方面的影响。虽然聚合氯化铝 (PAC) 生成的絮体从 198.0 μm 显著增加到 290.4 μm，同时 EDCs 的去除效率也得到提高，但聚合硫酸铁 (PFS) 生成的絮体除了略有减少外，尺寸没有明显变化。研究了在预混凝和无预混凝条件下进行臭氧氧化过程中 EDCs 的去除效率和光谱参数（包括 UVA254、UVA280 和类腐殖质荧光）的降低。在不同的水基质中，在低 O 剂量（O/溶解有机碳 (DOC) < 0.2）下，臭氧氧化过程能够有效地去除目标 EDCs。pH 滴定微分吸收光谱技术进一步表明，O 对 EDCs 的高反应性归因于它们的酚基。此外，当 mgO/mgDOC 比达到~0.40 时，超过 90%的雌激素活性被消除。简而言之，与单独臭氧氧化工艺相比，预混凝与臭氧氧化联合使用可在相同臭氧剂量下显著提高废水处理中 EDCs 和雌二醇 (E2) 等效值 (EEQ) 的去除率。
