School of Environmental and Chemical Engineering, Shanghai University, No. 99, Shangda Rd, Shanghai 200444, China E-mail:
Water Sci Technol. 2021 Apr;83(8):1824-1833. doi: 10.2166/wst.2021.107.
In this paper, combined with the addition of ethylenediaminetetraacetic acid (EDTA), the electrochemical treatment of waste activated sludge (WAS) was investigated to explore its effect on the release of phosphorus (P) from WAS. The results showed that during the electrochemical treatment, the addition of EDTA could significantly promote the release of P from the WAS to the supernatant, the optimal amount of EDTA was 0.4 g/g total suspended solids (TSS), when the release of total dissolved phosphorus (TDP), organic phosphorus (OP) and molybdate reactive phosphorus (PO-P) were 187.30, 173.84 and 13.46 mg/L, respectively. OP was the most likely form of P to be released during this process. Moreover, combined electrochemical-EDTA treatment could promote the release of P and metal ions from extracellular polymeric substances (EPSs) to the supernatant, and increase the solubility and disintegration of sludge. EDTA chelated the metal ions of sludge flocs and phosphate precipitates to cause sludge floc decomposition, thereby promoting the release of P from WAS.
本文结合乙二胺四乙酸（EDTA）的添加，研究了电化学处理剩余活性污泥（WAS）以探索其对 WAS 中磷（P）释放的影响。结果表明，在电化学处理过程中，EDTA 的添加可显著促进 P 从 WAS 向上清液中释放，EDTA 的最佳添加量为 0.4 g/g 总悬浮固体（TSS），此时总溶解磷（TDP）、有机磷（OP）和钼酸盐反应性磷（PO-P）的释放量分别为 187.30、173.84 和 13.46 mg/L。OP 是在此过程中最有可能释放的 P 形态。此外，电化学-EDTA 联合处理可以促进 P 和金属离子从胞外聚合物（EPS）释放到上清液中，增加污泥的溶解性和崩解性。EDTA 螯合了污泥絮体和磷酸盐沉淀物中的金属离子，导致污泥絮体分解，从而促进了 WAS 中 P 的释放。
