好氧接触氧化+Fenton组合工艺处理皮革废水

Aerobic contact oxidation + Fenton process for treatment of tannery wastewater

采用接触氧化工艺代替传统A^2O工艺中的活性污泥法来处理皮革废水,研究缺氧HRT、好氧HRT、混合液回流等因素对系统处理效果的影响。结果表明,在进水COD、氨氮以及TN分别为550~986,84~127,99~148 mg·L^(-1)的情况下,取消缺氧段以及混合液回流,控制好氧HRT=18 h,好氧柱DO为2.5~3.5 mg·L^(-1),好氧柱内发生了同步硝化反硝化,系统COD、氨氮以及TN的平均去除率分别为74.76%、98.35%以及67.63%。生化出水氨氮达到广东省《水污染排放限值》(DB 44/26-2001)第2时段一级标准。采用Fenton工艺深度处理生化出水,在m_(H_2O_2)/m_(COD)=1.5,m_(Fe^(2+))/m_(COD)=0.2,pH=3以及反应时间为4 h的反应条件下,可以将COD由150~220 mg·L^(-1)降至100 mg·L^(-1)以内。

Contact oxidation process was adopted to replace the activated sludge method in the conventional A-2O technique for processing tannery wastewater and to research the influence of anoxic HRT,aerobic HRT and mixed liquor recycle on the efficiency of the system. The results showed that when the influent COD,ammonia-nitrogen and TN were 550 to 986,84 to 127 and 99 to 148 mg·L^-1,respectively,the anoxic and mixed liquor recycle components were removed,the aerobic HRT was maintained at 18 h and the DO in the aerobic zone was controlled at 2. 5 to 3. 5 mg·L^-1,simultaneous nitrification and denitrification would occur in the aerobic zone and the average removal rates of COD,ammonia-nitrogen and TN would be 74. 76%,98. 35% and 67. 63%,respectively. The ammonia-nitrogen in the biochemical effluent met the first class discharge standard of second period level of Water Pollution Discharge Limits of Guangdong Province（ DB 44 /26-2001）. Fenton technique was used for the advanced treatment of the COD in the biochemical effluent. When mH2O2/ mCOD was 1. 5,mFe^2 ＋/ mCOD was 0. 2,pH was 3 and the reaction time was 4 h,COD could be reduced from 150 to 220 mg·L^-1 to less than 100 mg·L^-1.