紫外光强化电化学连续流处理垃圾渗滤液

UV-assisted Electrochemical Treatment of Landfill Leachate in a Continuous Flow Reactor

设计构建了一套放大的连续流一体化反应器,采用紫外光强化电化学法对某垃圾填埋场生化处理后的垃圾渗滤液进行处理,分别考察了水力停留时间、电流密度等因素对渗滤液化学需氧量(CODCr)及氨氮(NH3-N)去除效果的影响,并对电化学与紫外光强化电化学过程进行了对比。通过渗滤液UV-vis光谱(200～500nm)以及GC/MS分析,发现光电强化电化学过程中能生成大量的有机羧酸等小分子有机物,进而明显改善渗滤液生化性。结果表明:紫外光强化电化学过程可以有效处理垃圾渗滤液,在不调节pH且不添加电解质,水力停留时间为85min,施加电流密度为21.2mA/cm2条件下,垃圾渗滤液CODCr与NH3-N的去除率分别达到74.3%与94.9%,同时渗滤液的BOD5/CODCr达到0.6左右,提高了约12倍。

A magnified continuous-flow integrated reactor was developed and UV-assisted electrochemical（UAE）oxidation was adopted to treat leachate from a municipal sanitary landfill after biological process.The effects of hydraulic retention time and applied electric current density on the removal of CODCr and NH3-N were investigated,and UAE process and single electrochemical process compared to observe the synergetic effect.Based on analysis of UV-vis spectra（200-500 nm）and GC/MS,it was found that many small organic molecules such as organic carboxylic acids were generated in the process,which could be responsible for the improvement of biodegradability.The results showed that UAE process could treat landfill leachate effectively.Without pH adjustment and electrolyte addition,74.3% of CODCr and 94.9% of NH3-N could be degraded in the UAE process at a retention time of 85 min and electric current density of21.2 mA/cm2.Simultaneously,the BOD5/CODCr of leachate could reach at about 0.6,and its biodegradability increased by about 12 times.