造纸工业中水回用系统外排膜浓缩水达标排放设计

Design Case of Standardized Discharge of Membrane Concentrated Water from Water Reuse System in Papermaking Industry

湖北某工业园区污水处理厂接纳的来水主要为某造纸工业中水回用系统超滤及反渗透膜系统外排的浓缩水,膜浓缩水含盐量高,会抑制微生物的活性,导致污水的可生化性差,处理难度大。针对膜浓缩水的特殊性,污水处理工艺针对性地采用臭氧氧化-硝化及反硝化滤池-曝气生物滤池-芬顿氧化-活性炭吸附工艺,臭氧-曝气生物滤池用于去除来水中的色度、COD及其他有机污染物,硝化反硝化滤池用于脱氮,芬顿氧化用于进一步去除COD及TP,活性炭吸附工艺用于最后的出水水质保障。项目建成运行两年以来,出水水质稳定达到《城镇污水处理厂污染物排放标准》(GB 18918—2002)一级A标准,实现了膜系统浓缩水的达标排放处理。

Influent of a wastewater treatment plant in an industrial park in Hubei Province is mainly concentrated water discharged by ultrafiltration and reverse osmosis membrane of a paper industry’s reclaimed water reuse system.The high salt content of membrane concentrated water will inhibit the activity of microorganisms,resulting in poor biodegradability of wastewater and great difficulty in treatment.According to the particularity of concentrated water of membrane,the process of ozonation-nitrification and denitrification biological filter-biological aerated filter-fenton-activated carbon adsorption is adopted for the wastewater treatment.Ozone biological aerated filter is used to remove chroma,COD and other organic pollutants in the incoming water,nitrification and denitrification filter is used to remove nitrogen,Fenton oxidation is used to further remove COD and TP,and activated carbon adsorption process is used to guarantee the water quality of final effluent.Since the completion and operation of this project for two years,the effluent water quality has stably reached the first grade A of primary criteria specified in Discharge Standard of Pollutants for Municipal Wastewater Treatment plant(GB 18918-2002),achieving the standard discharge treatment of concentrated water in the membrane system.