Abstract:

Due to the frequent exceeding of toxic substances such as total cyanide in the inlet water，poor biochemical properties，etc，the sewage treatment plant of a coking industrial park had difficulties in the cultivation of activated sludge in the biochemical system，the large consumption of deeply treated powder activated carbon，and the COD and TN of the effluent difficult to stabilize. On the basis of the existing process，the primary treatment was transformed into ozone pre-oxidation and hydrolytic acidification tank，which improved the biodegradability of wastewater while breaking cyanide. The secondary treatment was transformed into A/A/O and MBR process，giving full play to the biochemical degradation of organic matter，nitrogen removal and phosphorus removal，and the low turbidity of MBR effluent reduced the ineffective amount of subsequent ozone. Advanced treatment was transformed into ozone oxidation. After the completion of the technical transformation at the end of 2017，this combination process showed a good operating effect，and the cost of post-technical transformation treatment was reduced by 3 yuan/m³ compared with that before the technical transformation. The main indicators such as effluent COD and ammonia nitrogen steadily reached the “Environmental Quality Standard for Surface Water”（GB 3838—2002） Class Ⅴ standard.

Key words: pre-ozonation, MBR process, coking wastewater

摘要：

某焦化工业园污水处理厂因进水中总氰等有毒物质频繁超标、可生化性差等问题导致生化系统活性污泥培养困难，深度处理粉末活性炭消耗量过大，出水COD、TN等难以稳定达标。在原有工艺的基础上，将一级处理改造为臭氧预氧化+水解酸化池，破氰的同时提高了废水的可生化性；二级处理改造为A/A/O+MBR工艺，充分发挥生化处理工艺的脱氮除磷、降解有机物作用，MBR出水的低浊性也减少了后续臭氧的无效投加量；深度处理改造为臭氧氧化。2017年底改造完成后，此组合工艺展现出良好的运行效果，处理成本比改造前降低了3元/m³，出水COD、氨氮等主要指标稳定达到《地表水环境质量标准》（GB 3838—2002）Ⅴ类标准。

关键词: 臭氧预氧化, MBR工艺, 焦化废水

CLC Number: 

• X703