电解催化氧化法废水处理机制研究

Study on electrochemical enhanced catalytic oxidation reaction for wastewater treatment

采用电解催化氧化法(electrochemical enhanced catalytic oxidation reaction)处理某高浓度有机废水(COD约10 000mg·L^(-1)),该工艺主要包括电解反应、催化氧化反应以及催化氧化反应后废水内循环进行电解反应等过程。开展了不同因素对废水COD降解效率影响的研究,并对反应降解机制和反应动力学进行了探讨。结果显示,内循环设计结合H_2O_2溶液投加量逐步增加的方式,使得体系在420 min反应时间内均保持着不断削减COD的能力。当FeSO_4·7H_2O初始投加量为0.6 g·L^(-1)、回流比R为0.5时,COD减少量可达9 340 mg·L^(-1)。反应过程中工作电流I及氧化还原电势ORP监测值的不断波动表明反应体系中有机物不断被降解,氧化还原环境不断地变化。该工艺耦合电解氧化和Fenton技术,协同因子约为1.48,且可极大提高废水混凝性能,反应60 min后经废水混凝处理可使COD去除率由4.27%提高至26.21%。

An electrochemically enhanced catalytic oxidation reaction was used for the treatment of highly concentrated organic wastewater（ COD of approximately 10 000 mg·L- 1）. This reaction was composed mainly of electrolytic reaction,catalytic oxidation reaction,and internal circulation reaction processes. Several factors were studied for their effect on COD degradation. Investigations on the degradation mechanism and reaction dynamics were also carried out. The results show that COD continually decreased with this reactor design and a gradual increase in the H_2O_2 solution dose. With an initial FeSO_4·7H_2O dose of 0. 6 g·L- 1and a reflux ratio of 0. 5,9 340 mg·L- 1of COD was degraded. Changes in the working current and ORP showed continued degradation of organic materials and constant change in the redox environment. In the concerned system,the electrochemical oxidation process was combined with the Fenton reaction. The cofactor of the system was around 1. 48,and the coagulation performance of wastewater improved greatly via this process,with the COD removal rate increasing from 4. 27% to 26. 1% after 60 min of reaction.