Abstract:

A sewage treatment plant with a treatment capacity of 10 000 m³/d was designed for dairy wastewater from an enterprise in Ningxia. The combined processes of fine grid，pretreatment unit for regulating water quality，two-stage anaerobic+A/O biochemical treatment，coagulation sedimentation and V-type filter were used to treat the dairy wastewater of this enterprise. In the treatment process，the anaerobic seed sludge was activated by adding independently developed engineering bacteria and medicament to speed up the start-up of the anaerobic reactor. In order to reduce the impact of scum on the sewage treatment system，air-floatation was set at the front end of each stage of anaerobic reactor to control the formation of a large number of scum in the anaerobic digestion process，and the scum discharged by air-floatation was anaerobic digested. When the denitrification carbon source was insufficient，the carbon source was supplemented by exceeding part of the flow from the intermediate tank to anoxic denitrification tank. After 45 d of commissioning and operation，the sewage treatment system operated stably，the pollutant removal effect was good，and the effluent quality met level 1A discharge standard of Pollutant Discharge Standard for Urban Wastewater Treatment Plant（GB 18918—2002）.

Key words: dairy wastewater, sewage treatment plant, anaerobic, microbial agent, air-flotation

摘要：

针对宁夏某企业乳品废水，设计日处理量10 000 m³的污水处理厂。采用细格栅、调节水质的预处理单元、两级厌氧+A/O生化处理、混凝沉淀、V型滤池等工艺，对该企业乳品废水进行处理。处理过程中，通过投加自主研发工程菌剂和药剂，对厌氧种子污泥进行活化，加快厌氧反应器的启动；为减轻浮渣对污水处理系统的影响，在每级厌氧反应器前端设气浮，控制厌氧消化过程浮渣的大量形成，并对气浮排出的浮渣进行厌氧消化处理；当反硝化碳源不足时，从中间水池超越部分流量至缺氧反硝化池补充碳源。经过45 d的调试运行，污水处理系统运行稳定，污染物去除效果较好，出水水质达到《城镇污水处理厂污染物排放标准》（GB 18918—2002）一级A标准。

关键词: 乳品废水, 污水处理厂, 厌氧, 菌剂, 气浮

CLC Number: 

• X703