采用光电芬顿氧化法对北京市某垃圾填埋场已经生化处理后的垃圾渗滤液进行深度处理,分别考察了电流强度和铁的不同价态等因素对渗滤液总有机碳(TOC)、化学需氧量(COD)以及色度去除效果的影响,并对阳极氧化、电芬顿和光电芬顿不同反应过程进行了对比。通过分析渗滤液UV—Vis光谱(200~500nm)变化和渗滤液中有机污染物的分子量变化,发现光电芬顿反应可以明显改善渗滤液生化性。深入研究了反应过程中铁价态的变化规律。试验结果发现,以高比表面积的活性炭纤维(ACF)为阴极的光电芬顿反应可以有效降解垃圾渗滤液,在pH为3,Fe^2+浓度为1mmol/L,电流为0.5A,O2通入量为250mL/min条件下降解360min,垃圾渗滤液TOC和COD去除率分别达到78.9%和62.8%,色度完全去除。
Photo-electro-Fenton oxidation method was used to treat landfill leachate, which was pre-treated by biochemical process and sampled from a landfill in Beijing City. The effects of current strength and iron valence on total organic carbon (TOC) , chemical oxygen dose ( COD), and color removal were investigated. Meanwhile, several different reactions of anodic oxidation, electro-Fenton, and photo-electro-Fenton were compared. The UV-Vis spectrometry of landfill leachate as well as the molecular weight distribution of organic pollutants (measured via Gel chromatography) was analyzed. The biodegradability was improved greatly. Variation of iron concentration in the reaction process was also tested. The photo-electro-Fenton reaction using ACF cathode could degrade landfill leachate effectively. After 360 min electrolysis and under the operation conditions of 0.5 A current, 1 mmol/L Fe^2+ , 250 mL/min 02 at pH 3, 78.9% of TOC and 62.8% of COD were removed respectively as well as complete decolorization.