电凝聚臭氧化耦合工艺的有机物处理特性及去除机制解析

以污水厂二级出水溶解性有机物强效去除为目的，本研究构建了电凝聚臭氧化耦合（E-HOC）体系，明确了该体系对污水厂二级出水及布洛芬的处理特性，探明了有机物的强化去除机制.结果表明，在pH5条件下，E-HOC工艺对二级出水溶解性有机物的去除效果更优，相较于臭氧氧化、电絮凝工艺、预臭氧化-电絮凝工艺、电絮凝串联臭氧工艺以及化学混凝工艺分别提高了46.4%、20.0%、19.4%、36.1%和49.7%.为进一步明确该耦合工艺去除溶解性有机物的机制，基于淬灭实验和EPR特征峰谱图分析，证实了金属盐混凝剂可作为催化剂有效地提高羟基自由基（·OH）的产量，揭示了该耦合体系存在臭氧混凝协同增效（SOC）反应.傅立叶红外的分析结果表明，Al阳极电解产生的混凝剂水解物表面羟基为SOC反应中产生·OH的活性位点.基于有机物在E-HOC体系中的动力学特性，解析了耦合体系中有机物的去除机制，SOC反应和臭氧氧化反应在E-HOC体系的有机物去除过程中作用显著，SOC反应为·OH的生成提供了一种新的途径.

Characteristics and Removal Mechanism of an Electro-Hybrid Ozonation-Coagulation System in the Treatment of Organic Matters

To improve the removal efficiency of dissolved organic matter in wastewater treatment plant (WWTP) effluent, electro-hybrid ozonation-coagulation (E-HOC) is proposed and the treatment characteristics and removal mechanism for WWTP effluent and ibuprofen (IBP) are investigated. The E-HOC process has a better removal effect on dissolved organic matter in WWTP effluent, achieving 46.4%, 20.0%, 19.4%, 36.1%, and 49.7% higher removal than EC, ozonation, pre-ozonation-EC, electrocoagulation-ozonation, and chemical coagulation, respectively. To determine the mechanism of the E-HOC process, quenching experiments and electron paramagnetic resonance (EPR) were conducted, which confirmed that metal coagulants can be used as a catalyst to effectively increase the generation of the hydroxyl radical (·OH). Synergistic effects between ozone and the coagulants (SOC) were also found to be involved. Fourier-transform infrared spectroscopy (FT-IR) illustrated that the surface hydroxyl groups of the coagulant (hydrolyzed species produced by Al anode electrolysis) were the active sites for the generation of·OH in the SOC reaction. Based on a kinetics analysis of organic matter removal in the E-HOC system, SOC effects and ozonation played dominant roles in the E-HOC process. Additionally, the SOC created a new pathway for·OH formation.