UASB/MBR-CANON工艺处理高氮活性印花废水

Treating high nitrogen-containing reactive printing wastewater with UASB/MBR-CANON process

针对棉织物活性印花废水高氮、高色度、高COD等特点,采用上流式厌氧污泥床反应器与完全自养脱氮膜生物反应器组合工艺(UASB/MBR-CANON),处理模拟高氮活性印花废水。实验过程分为独立启动和串联运行2个阶段,探究了不同基质浓度条件下UASB/MBR-CANON反应器对高氮活性印花废水的处理效果。结果表明:UASB和MBR-CANON反应器分别经过140 d独立启动运行后,UASB反应器与MBR-CANON反应器完成串联运行,此时总氮平均去除率达到72%,COD平均去除率达到74%,染料平均脱色率达到82%;在MBRCANON反应器运行的200 d内,通过对膜表面污染物分析发现,膜表面滤饼层胞外聚合物中多糖和蛋白质含量分别为52 mg·L^-1和17 mg·L^-1。膜通量数据表明,在低通量状态下,膜通量衰减速率较为缓慢,经过清洗后,膜通量可恢复初始通量的80%~90%。进一步分析可知,采用UASB/MBR-CANON工艺处理高氮活性印花废水具有较高的技术可行性,以上研究结果可为该工艺的工程化应用提供参考。

Aiming at the characteristics of cotton fabric wastewater:high nitrogen content,high chroma and high COD,a combined process with an up-flow anaerobic sludge bed(UASB)and a completely autotrophic nitrogen removal over nitrite(CANON)-membrane bioreactor(MBR)was developed to treat the simulated high nitrogen-containing active printing wastewater.The experiment process was divided into two stages,i.e.an independent start-up stage and a serial operation stage.The treatment efficiency of the simulated printing wastewater by UASB/MBR-CANON process under different substrate concentrations was investigated.After 140 days-independent start-up of the UASB and MBR-CANON reactors,the UASB effluent was gradually fed to the MBR-CANON reactor.Then the average removal efficiencies for TN,COD and chroma by the combined process reached 72%,74% and 82%,respectively.Within the 200 days-running of the combined process,the contents of polysaccharide and protein in extracellular polymeric substances of membrane cake layer were 52 mg·L^-1 and 17 mg·L^-1,respectively.The change of membrane flux indicated that the decay rate of flux was slow at a low flux stage,and 80%~90% initial flux could be recovered after cleaning.Results indicated that the combined process is a feasible solution for treating the active printing wastewater,and can provide reference for its industrial application.