电化学氧化—絮凝系统协同去除水中砷的研究

Synergistic Removal of Arsenic by Electrochemical Oxidization and Flocculation System

针对传统电絮凝所存在的曝气增氧、电极反应能耗高的关键问题,研究开发了空气阴极,并与铁阳极组成电化学氧化—絮凝协同除砷系统,比较了在相同电压下,新型电化学氧化—絮凝系统与传统电絮凝系统在砷去除效率、能耗上的区别。结果表明:当给定相同电压时,空气阴极电絮凝系统的电流密度较传统电絮凝系统要高得多。在2.0 V电压下,空气阴极电絮凝系统对As(Ⅲ)与总砷的去除反应速率常数约为曝气电絮凝系统的3倍。与曝气电絮凝相比,空气阴极电絮凝无需曝气,能节省50%的电极反应能耗,可节省74%的总能耗。

Aiming at the key problems of high energy consumption of aeration and electrode reaction in traditional electrocoagulation, an electrochemical oxidation-flocculation system composed of air cathode and iron anode was developed for arsenic removal. Arsenic removal efficiency and energy consumption of the new electrochemical oxidation-flocculation system and traditional electrocoagulation system at the same voltage was compared. Current density of air cathode electrocoagulation was much higher than that of traditional electrocoagulation system at the same voltage. When the voltage was 2.0 V, the reaction rate constant of As(Ⅲ) and total arsenic removal in air cathode electrocoagulation was three times of that in aerated electrocoagulation. Compared with aerated electrocoagulation, there was no aeration in air cathode electrocoagulation, which could save 50% energy consumption of electrode reaction and 74% total energy consumption.