腈纶废水处理工艺改进与工程实践

Improvement and Engineering Practice of Acrylic Fiber Wastewater Treatment Process

结合国家"十一五"水专项成果,介绍了东北某大型化纤厂腈纶废水处理工程改造效果。工程实践表明,采用预处理气浮/连续砂滤/水解酸化/折流板生化反应器/深度气浮工艺可以使腈纶废水经过处理后出水COD达到《污水综合排放标准》(GB 8978—1996)的二级标准。与传统加压气浮相比,浅层气浮更适合于腈纶废水的预处理;采用微生物固定化载体并辅以折流板式生化反应池,可有效解决传统活性污泥法二沉池污泥上浮、生化池污泥浓度低的问题,提高了处理效果;采用混凝剂,可有效降低生化处理出水的COD,为出水的达标排放提供保证。

Combined with the achievements of the national water project in 11 th Five-Year Plan, the reconstruction effect of a large acrylic fiber wastewater treatment project in northeast China was intro- duced. The engineering practices showed that the processes of pretreatment air flotation, continuous sand filter, hydrolysis acidification, baffled biochemical reactor and advanced air flotation could make the ef- fluent COD meet the second class criteria specified in Integrated Wastewater Discharge Standard （GB 8978 - 1996）. The effect of shallow air flotation was better than that of traditional pressurized air flotation during the pretreatment of acrylic fiber wastewater. The problems in traditional activated sludge process, like sludge bulking in elarifier and low sludge concentration in biochemical tank could be solved using im- mobilized microbial technology along with baffled biochemical reactor, thus improving the treatment effi- ciency. The oxidation coagulating agent could effectively reduce the COD in biochemical treatment efflu- ent, and consequently ensure that the effluent met the discharge standard.