高级氧化-生化组合工艺处理垃圾渗滤液的研究

Treatment of landfill leachate with a hybrid process of advanced oxidation-biochemistry

针对垃圾渗滤液有机污染大、氨氮浓度高、可生化性差的特点,利用铁屑和颗粒活性炭(GAC)构成腐蚀电池反应所产生的Fe2+,以及通入空气中O2在阴极被还原产生的H2O2组成连续Fenton试剂对其进行处理。在反应pH为2.5,反应时间为90 min,铁屑投加量为40 g.L-1,Fe/C为3.5,絮凝pH为9的反应条件下,COD、TOC和NH4+-N的去除率分别可达到70.8%,59.6%和15.1%,BOD5/COD从原水的0.16提高到0.27,有利于垃圾渗滤液的后续处理。高级氧化-生化组合工艺采用空气中O2取代H2O2,大大降低了该技术应用于渗滤液处理的运行费用。

Landfill leachate is generally characterized as low -biodegradable wastewater containing high concentration of chemical oxygen demand （COD） and ammonium - nitrogen （ NH4 - N）. This study investigated the treatment of landfill leachate by using continuous Fenton system in combination with aeration and corrosive cell between iron scraps and granular activated carbon （GAC）. In such system, Fe^2＋ ions were continuously generated via corrosive cell, and H2O2was produced by O2 deoxidized on the cathode. The results demonstrated that based on the optimal conditions of reaction pH 2. 5, reaction time 90 mix, iron scrape concentration 40 g· L^-1, Fe/C 3.5 and flocculating pH 9.0, removal efficiency of COD, TOC, NH4^＋ - N reached 70.8% , 59.6% and 15.1% respectively. Besides, BOD5/COD value was increased from 0. 16 （ raw leachate） to 0.27 （ treated solution） , which made the effluent more suitable for the following biotreatment. The replacement of H2O2by O2from free air can reduce operational cost of treatment process.