摘要
炼化污水反渗透浓水具有高盐度、高污染、难生化降解等特性,常规工艺处理难度大。采用电化学法处理炼化污水反渗透浓水,通过单因素实验确定了最佳电化学条件。结果显示:选用锡锑极板和铁板分别为阳极和阴极,硫酸钠为电解质,设置阴阳极面积比为1.5∶1,TOC和TN去除率分别可达46%和35%。进一步优化电化学条件表明:电流密度过大会促进电解水副反应发生,降低有机物降解的电子利用效率;电解质虽然能增加电导率,但是过量添加会降低电极电势,影响有机物在阳极表面的降解效率;碱性体系利于·OH的产生,但pH的增加会导致有机物的矿化产物以CO_(3)^(2-)形式存在,淬灭·OH,降低氧化性能。因此,当电流密度为20.0 mA/cm^(2),SO_(4)^(2-)浓度为9.0 g/L,pH为8.5,电解2.5 h后,出水TOC与TN浓度分别为15 mg/L和14 mg/L,去除率最高,可达56%和55%。实验证明:电化学处理可有效降低炼化污水反渗透浓水污染负荷,减轻常规工艺的处理压力,为实现炼化企业污水零排放提供技术支撑。
The reverse osmosis concentrated water from refining wastewater has the characteristics of high salinity,high pollution,and difficult biochemical degradation,making it difficult to treat with conventional processes.The electrochemical method was used to treat concentrated reverse osmosis water from refining wastewater,and the optimal electrochemical conditions were determined through single factor experiments.The results showed that using tin antimony plates and iron plates as anodes and cathodes,sodium sulfate as electrolyte,and setting the anode cathode area ratio to 1.5∶1,the removal rates of TOC and TN could reach 46%and 35%,respectively.Further optimization of electrochemical conditions indicated that excessive current density promoted the occurrence of side reactions in water electrolysis and reduced the electron utilization efficiency of organic matter degradation.Although electrolytes can increase conductivity,excessive addition can lower electrode potential and affect the degradation efficiency of organic matter on the anode surface.The alkaline system was conducive to the production of·OH,but an increase in pH can lead to the mineralization products of organic matter existing in the form of CO_(3)^(2-),quenching·OH and reducing oxidation performance.Therefore,when the current density was 20.0 mA/cm^(2),the SO_(4)^(2-) concentration was 9.0 g/L,the pH was 8.5,and after electrolysis for 2.5 h,the effluent TOC and TN concentrations were 15 mg/L and 14 mg/L,respectively,with the highest removal rates of 56% and 55%.The experimental results showed that electrochemical treatment can effectively reduce the pollution load of reverse osmosis concentrated water in refining wastewater,alleviate the treatment pressure of conventional processes,and provide technical support for achieving zero discharge of wastewater in refining enterprises.
作者
李晓旭
徐俊发
刘璐
李晋
Li Xiaoxu;Xu Junfa;Liu Lu;Li Jin(Guangdong Petrochemical Co.,Ltd.,Guangdong,Jieyang,515200;College of Science,China University of Petroleum(Beijing),Beijing,102249;Beijing North Energy Conservation and Environmental Protection Co.,Ltd.,Beijing,100070)
出处
《安全、健康和环境》
2025年第1期30-37,共8页
Safety Health & Environment
关键词
反渗透浓水
电化学
单因素
TOC去除率
TN去除率
reverse osmosis concentrated water
electrochemistry
single factor
TOC removal rate
TN removal rate
作者简介
第一作者:李晓旭,工程师,2013年毕业于黑龙江大学高分子材料与工程专业,现主要从事炼化企业物资采购、公用工程等工作。E-mail:lixx-gd@petrochina.com.cn;通信作者:李晋,讲师,2023年博士毕业于中国石油大学(北京)化学工程与技术专业,主要研究方向为石油石化污染控制与处理。E-mail:lijincup@163.com。
