化肥工业废水处理O/A/O脱氮工艺研究

O/A/O Nitrogen Removal Process for Treatment of Fertilizer Industrial Wastewater

根据化肥工业废水氨氮含量高、波动大等特点,设计了初曝池-兼气池-好氧池(O/A/O)组合工艺。利用模拟废水考察了水力停留时间(HRT)、溶氧(DO)浓度、硝化液回流比和污泥回流比对除氮效果的影响。在模拟废水实验参数基础上,得出实际运行参数为:污泥回流比100%,硝化液回流比400%,缺氧池DO<0.5mg·L^(-1),好氧池DO 3mg·L^(-1)。采用O/A/O组合工艺对化肥工业产生的COD在100~1 100mg·L^(-1)、氨氮在20~130mg·L^(-1)范围波动的实际废水进行处理,出水COD均值为35.5mg·L^(-1),出水氨氮均值为1mg·L^(-1),达到《综合污水排放标准》(GB 8978-1996)的一级标准。该技术具有较好的推广应用价值。

A primary aeration pool-anaerobic and aerobic pool-aerobic pool （O/A/O） integrated process was designed according to the characteristics of high ammonia nitrogen content and big fluctuation for fertilizer industrial wastewater. The effects of hydraulic retention time（HRT）, dissolved oxygen（DO） concentration, nitri- fication liquid reflux ratio, sludge reflux ratio on nitrogen removal efficiency were investigated by using the sim- ulated wastewater..On the basis of parameters of simulated wastewater experiment, the practical process param- eters were obtained as follows： sludge reflux ratio of 100%, nitrification liquid reflux ratio of 400% ,DO concen- tration of anoxic pool low than 0.5 mg·L^-1 ,DO concentration of aerobic pool 3 mg ·L^-1. The effluent quality can reach the first class of Integrated Standard of Wastewater Discharge（ GB 8978-1996） with the average effluent COD 35.5 mg·L^-1 ,effluent ammonia nitrogen 1 mg·L^-1 through the treatment of the fertilizer industrial wastewater with COD range from 100 mg·L^-1 to 1 100 mg ·L^-1 ,ammonia nitrogen range from 20 nag ·L^-1 to 130 mg·L^-1. There are wide applications for O/A/O integrated process.