摘要：

用硫酸法生产钛白粉时会产生大量高温酸性废水，经电石渣中和后氨氮含量高、碳氮比低。采用化学氧化法进行脱氮费用高，且无法达到去除总氮的目的。针对此类废水，采用A/O活性污泥法替代化学氧化法进行中试研究。在进水温度为40~50 ℃、COD为36.6~71.4 mg/L、氨氮为6.5~17.8 mg/L、总氮为11.1~27.8 mg/L的条件下，控制DO在3.5~4.5 mg/L、污泥回流比为60%、混合回流比90%、碳源投加量55 mg/L，结果显示，接种活性污泥经过驯化，出水COD为25~35 mg/L，氨氮在1 mg/L以下，总氮在6~9 mg/L，可稳定达到《四川省岷江、沱江流域水污染物排放标准》（DB 51/2311—2016）中的工业园区集中式污水处理厂排放标准要求。经核算，吨水运行成本为0.628元。通过逐步提高温度和水力负荷的驯化方法，达到去除此类化工废水中污染物的效果，可为工程应用提供指导和参考。

关键词: 化工废水, A/O工艺, 脱氮, 酸性废水

Abstract:

The production of titanium dioxide by sulfuric acid method generates a large amount of high-temperature acidic wastewater, which has high ammonia nitrogen content and low C/N ratio after neutralization by carbide slag. The cost of denitrification by chemical oxidation method is high, and the purpose of total nitrogen removal cannot be achieved. To treat this type of wastewater, A/O activated sludge process was used to replace chemical oxidation in this pilot-scale study. Under the condition of influent temperature under 40-50 ℃, COD within 36.6-71.4 mg/L, ammonia nitrogen within 6.5-17.8 mg/L and total nitrogen in the range of 11.1-27.8 mg/L, controlling DO of 3.5-4.5 mg/L, sludge reflux ratio of 60%, mixed reflux ratio of 90%, carbon source dosage of 55 mg/L, the results showed that, after cultivation of inoculum activated sludge, effluent could achieve COD of 25-35 mg/L, ammonia nitrogen below 1 mg/L, and total nitrogen of 6-9 mg/L, which stably met the standard of centralized wastewater treatment plant for industrial park in the Discharge Standard of Water Pollutants for Minjiang and Tuojiang River Basins of Sichuan Province(DB 51/2311—2016). After calculation, the operating cost per ton of water was 0.628 yuan. For this kind of chemical wastewater, the acclimation method of gradually increasing temperature and hydraulic loading could achieve the removal effect of pollutants, which provided guidance and reference for engineering application.

Key words: chemical wastewater, A/O process, denitrification, acid wastewater

中图分类号: 

• X703