以活性炭纤维为阴极的光电化学法协同处理垃圾渗滤液  

Synergetic Treatment of Landfill Leachate in the Photoelectrochemical Process with Activated Carbon Fiber as Cathode

作　　者：肖书虎[1] 宋永会[1] 肖宏康[1] 张国芳[1] 

机构地区：[1]中国环境科学研究院城市水环境研究室,北京100012

出　　处：《环境工程技术学报》2011年第4期353-358,共6页Journal of Environmental Engineering Technology

基　　金：国家水体污染控制与治理科技重大专项(2008ZX07208-003);中国博士后科学基金项目(20100470399);中国环境科学研究院中央级公益性科研院所基本科研业务专项资助项目(2010KYYW15)

摘　　要：以活性炭纤维（ACF）为阴极,RuO2/Ti形稳电极为阳极,研究了电氧化、电氧化/电芬顿及光电化学组合3种过程对垃圾渗滤液的处理效果,考察了初始pH和电流密度对光电化学法降解渗滤液TOC的影响,并探讨了渗滤液有机物形态及可生化性的变化规律。结果表明,光电化学组合法对渗滤液TOC的处理效果及降解一级动力学常数远高于电氧化及电氧化/电芬顿过程之和,原位生成H2O2与活性氯在紫外光辐照/Fe2＋条件下生成羟基与氯自由基是该光电化学体系的主要协同机理。电流密度是渗滤液TOC降解的控制因素,TOC的降解速率随电流密度升高而逐渐提高。在初始pH为2.0-5.1,电流密度为15.0 mA/cm2及Fe^2＋投加量为1 mmol/L条件下,300 min内垃圾渗滤液TOC的去除率达80%左右,TOC降解动力学常数为6.1×10^-3-6.6×10^-3min^-1。紫外可见光谱（UV-Vis）及排阻凝胶色谱（GPC）结果表明,光电化学体系能有效将难降解的腐殖酸/富里酸转化为小分子物质乃至矿化,使渗滤液的可生化性得到明显改善,BOD5/CODCr提升至0.42。Photoelectrochemical treatment of landfill leachate with activated carbon fiber（ACF） as cathode and RuO2Ti as anode was carried out.The treatment efficiencies were compared among electro-oxidation,electro-oxidationelectro-Fenton and photoelectrochemical processes,and the effects of initial pH and current intensity on degradation of leachate TOC by photoelectrochemical method were studied.Simultaneously,the variation rules of organic speciation and biodegradability were investigated.The results showed that the degradation efficiency of TOC and the first-order kinetic constant were far higher than the sum of electro-oxidation and electro-oxidationelectro-Fenton,and thus the hybrid photoelectrochemical process presented a good synergetic effect.The formations of hydroxyl and chlorine radicals,which were disassociated from H2O2 and active chlorine by UV and Fe2＋,were proposed to be the main mechanism.Current density was the control factor and the degradation rate of TOC increased gradually with increasing current density.Under the conditions of initial pH of 2.0-5.1,current intensity of 15.0 mAcm2 and Fe2＋ addition of 1 mmolL,the removals of TOC reached about 80% within 300 min and the first-order kinetic constants ranged between 6.1×10-3-6.6×10-3 min-1.The UV-Vis and gel permeation chromatography（GPC） spectra showed that the biorefractory humic and fulvic substances could be transformed into small molecules or even be mineralized,which resulted in the increasing of biodegradability and the BOD5CODCr reached about 0.42.

关 键 词：光电化学 活性炭纤维 垃圾渗滤液 协同效应 可生化性 

分 类 号：X799.3[环境科学与工程—环境工程]