School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
Hunan BISEN Environmental & Energy Co. Ltd., Changsha 410100, China.
J Hazard Mater. 2021 Jul 5;413:125404. doi: 10.1016/j.jhazmat.2021.125404. Epub 2021 Feb 12.
Ozone treatment has been proven as an effective technology for removing PAHs in municipal sewage sludge. However, given the complex interaction of PAHs with sludge extracellular polymeric substances (EPS), effective sludge disintegration is required to make PAHs more accessible to oxidants, which also affects PAHs partitioning. Here, we investigated two treatment systems, namely ozonation (ozone) and sequential hydrodynamic cavitation and ozonation (HC+ozone), under varied conditions, to determine whether the extent of sludge disintegration can estimate a measurable removal of PAHs. The results showed that both the PAHs removal efficiency and kinetics highly depended on pH and ozone dose. Although no significant removal of PAHs occurred during HC treatment, the observed rate constants for Σ PAHs removal in HC+ozone system were 1.2-1.4-fold higher than those obtained in ozone system under the same condition. The accelerated PAHs removal could be attributed to the reduced flocs size (80% smaller) and increased soluble EPS concentration (5-fold higher) with HC pretreatment. Lastly, a positive correlation was noted between the PAHs removal efficiency and soluble EPS concentration (R = 0.85), indicating the important role of dissolved and colloidal matter (DCM) for PAHs partitioning between aqueous and particulate phases.
臭氧处理已被证明是去除城市污水污泥中多环芳烃的有效技术。然而，鉴于多环芳烃与污泥胞外聚合物（EPS）的复杂相互作用，需要进行有效的污泥解体，以使多环芳烃更容易接触氧化剂，这也会影响多环芳烃的分配。在这里，我们研究了两种处理系统，即臭氧处理（臭氧）和顺序水力空化和臭氧处理（HC+臭氧），在不同条件下，以确定污泥解体的程度是否可以估计多环芳烃的可测量去除。结果表明，多环芳烃的去除效率和动力学高度依赖于 pH 值和臭氧剂量。虽然在 HC 处理过程中没有发生多环芳烃的明显去除，但在相同条件下，HC+臭氧系统中Σ多环芳烃去除的观察到的速率常数比臭氧系统中的速率常数高 1.2-1.4 倍。加速的多环芳烃去除可归因于 HC 预处理后减少的絮体大小（小 80%）和增加的可溶性 EPS 浓度（高 5 倍）。最后，注意到多环芳烃去除效率与可溶性 EPS 浓度之间存在正相关关系（R=0.85），表明溶解和胶体物质（DCM）在多环芳烃在水相和颗粒相之间分配中的重要作用。
