【作者】 李明波；

【导师】 金奇庭；

【作者基本信息】 西安建筑科技大学 ， 环境工程， 2004， 硕士

【摘要】 垃圾渗滤液是垃圾填埋过程中的产物，是一种高浓度有毒有害有机废水，其水质水量变化大、成份复杂，而且随着垃圾填埋年龄的增加，垃圾渗滤液将发生稳定化作用，使生物降解性变差，其处理问题一直是个世界性的难题。以产生强氧化性羟基自由基为主要氧化剂的光化学氧化工艺，能在非常短的时间内降解污染物，在处理有机废水中有着广泛的应用前景。 本文系统研究了光化学氧化工艺（UV／O₃、UV／H₂O₂、UV／H₂O₂／O₃）处理稳定化垃圾渗滤液的效果和相关的影响因素。垃圾渗滤液来源于西安市江村沟垃圾填埋场，主要水质指标为：pH8.2、COD2628mg／L、BOD₅430mg／L、NH₃-N3100mg／L、色度800倍、碱度（CaCO₃）13000mg／L，光化学氧化前进行了氨吹脱预处理。结果表明，[O₃]=1.4g／（L·h），UV／O₃氧化2.5hCOD去除率为55～80％、NH₃-N去除率＞96％、色度去除率100％；[H₂O₂]=1～8g／L，UV／H₂O₂氧化3hCOD去除率为19～38％、NH₃-N去除率为18～27％、色度去除率＞50％；[O₃]=1.4g／（L·h）、[H₂O₂]／[O₃]=0.1～1.0，UV／H₂O₂／O₃氧化2.5hCOD去除率为65～86％、NH₃-N去除率＞96％、色度去除率100％。说明光化学氧化工艺对垃圾渗滤液具有良好的处理效果。 该垃圾渗滤液的BOD₅／COD值小于0.19，经UV／O₃预氧化处理后（[O₃]=450mg／L），BOD₅／COD值升高至0.4左右，生物降解性得到很大改善。应用超滤膜分离技术测定垃圾渗滤液中有机物分子量分布的结果表明，垃圾渗滤液中有机物主要为分子量大于10KD（＞83％）的大分子有机物，经过UV／O₃氧化后转化为分子量小于3KD（＞98％）的小分子有机物。同时，间歇式活性污泥筛选法试验结果证明，UV／O₃工艺的预氧化效果十分明显，能显著改善垃圾渗滤液的生物降解性，从而有利于后续生物处理。 建立了UV／O₃工艺氧化垃圾渗滤液的拟一级反应动力学模型，并证明动力学模型符合实际。更多还原

【Abstract】 In this dissertation, laboratory experiments were conducted to compare the efficacies to treat stabilized landfill leachate, by several photochemical oxidation processes, such as UV/H2O2, UV/O3, and UV/H2O2/O3. The leachate came from a municipal sanitary landfill located in northwest China and the average values of its main parameters were: pH8.2; COD2628mgL-1; BOD5430mgL-1; NH3-N3100mgL-1. NH3-N of raw leachate was initially desorbed at pH11.0, and then the photochemical oxidation processes were applied. The results showed only 18~27%COD removal was reached by UV/H2O2 with hydrogen peroxide doses between 1 and 8gL-1, however, 55~80%COD removal was obtained by UV/O3 with an ozone dosage of 3.5gL-1, and 65~86%COD removal was achieved by UV/H2O2/O3 with an ozone dosage of 3.5gL-1 in the presence of hydrogen peroxide doses between 0.35 and 3.5 gL-1.Biodegradability of landfill leachate, measured as BOD5/COD, increased from less than 0.19 to nearly 0.4 by UV/O3 with an ozone dosage of 450 mgL-1. UF separation showed that the predominant COD distribution before and after UV/O3 oxidation were higher than10KD(>83%) and lower than 3KD(>98%) respectively, which revealed the significant reduction of nonbiodegradable organic matters of leachate. In addition, results of Batch Activated Sludge processes treatment showed a substantial argument for the increase on biodegradability of oxidized leachate, which demonstrated that UV/O3 would be beneficial to the subsequent biological treatment processes.A Pseudo-first-order kinetics model for COD removal by UV/O3 was proposed and proved.更多还原