UV-Fenton体系处理准好氧矿化垃圾床渗滤液尾水中难降解有机物  

Treatment of recalcitrant organics of semi-aerobic aged refuse bioreactor leachate tail water by UV-Fenton process

作　　者：冯梅 陈炜鸣 潘旭秦 李启彬 刘丹 FENG Mei;CHEN Weiming;PAN Xuqing;LI Qibin;LIU Dan(Faculty of Geosciences and Environmental Engineering,Southwest Jiaotong University,Chengdu 611756)

机构地区：[1]西南交通大学地球科学与环境工程学院

出　　处：《环境科学学报》2019年第9期2980-2987,共8页Acta Scientiae Circumstantiae

基　　金：四川省重大科技专项(No.19ZDZX0009)

摘　　要：采用紫外(UV)耦合Fenton反应产生活性氧物种降解准好氧矿化垃圾床渗滤液尾水中的难降解污染物.考察了初始pH值、双氧水和二价铁(Fe^2+)投加量对污染物去除效能的影响,并采用醇类猝灭实验和三维荧光技术解析了体系产生的主要活性氧物种及其腐殖质的降解机制.结果表明,UV-Fenton体系可协同、有效地处理准好氧矿化垃圾床渗滤液尾水中的污染物.增大双氧水和二价铁投加量可提高体系降解有机物的能力与反应速率,初始pH值为3.0时有机物降解效果最佳,中性与碱性环境均会显著抑制体系对有机物的降解.在H2O2投加量为0.084 mol·L^-1,Fe^2+投加量为0.056 mol·L^-1,初始pH值为3.0的条件下,渗滤液尾水COD去除率与反应速率常数最终分别为77.22%和0.04679.经UV-Fenton体系处理后,得益于体系主要的活性氧物种·OH与O·2^-对渗滤液尾水中芳香类有机物质的有效降解,同时,可见区荧光峰值降低了51.00%,紫外区荧光峰值先增大后减小.因此,渗滤液中大分子物质大幅减少,小分子物质相对增多.In this study,ultraviolet(UV)-coupled Fenton process was used to produce reactive oxygen species(ROS)to degrade refractory organic pollutants in leachate tail water from semi-aerobic aged refuse bioreactor(SAARB).The effects of initial pH value,H2O2 dosage,and Fe2+dosage on removal efficacy of organic matter were investigated.In addition,alcohol quenching experiments were carried out to identify predominant ROS in the UV-Fenton process.Three-dimensional excitation and emission(3 D-EEM)spectra were used to reveal the degradation mechanism of humic substances by UV-Fenton process.Results showed that UV-Fenton process was able to co-efficiently and effectively degrade organic pollutants in leachate tail water from SAARB.Removal efficacies of organic matter can be greatly enhanced by increasing H2O2 and Fe^2+dosages.Acidic ambient(especially pH=3.0)favored treatment efficacy,but neutral and base ambient depressed the treatment efficacy.Under conditions of initial pH=3.0,H2O2 dosage 0.084 mmol·L^-1,and Fe^2+dosage 0.056 mmol·L^-1,the removal efficiency and removal rate of COD were 77.22%and 0.04679,respectively.Owing to the contribution of·OH and O·2^-,aromatic substances in leachate tail water were greatly degraded.Meanwhile,the fluorescent peak value of fulvic substances in visible light region decreased by 51.00%,and the fluorescent peak value of fulvic substances in ultraviolet light region increased at first and then decreased,leading to a significant content decrease of macromolecular organic matters and an increase of small organic matters.

关 键 词：紫外 芬顿 准好氧矿化垃圾床 垃圾渗滤液 自由基 

分 类 号：X703[环境科学与工程—环境工程]