基于原位碳源补充强化污水处理深度脱氮技术的中试

Pilot Test of Advanced Denitrification for Enhanced Wastewater Treatment Based on In-Situ Carbon Source Supplement

针对某污水处理厂出水TN无法稳定达标问题,拟采用反硝化生物滤池工艺,同时利用污水厂原水水解酸化池产生的挥发性脂肪酸和乙酸钠溶液联用作为反硝化外加碳源,强化对二级出水深度脱氮处理。中试试验结果表明,在挂膜成功后,采用水解酸化VFAs与乙酸钠混合作为外加碳源,按照COD/NO_3^-N=5:1(COD_(乙酸钠):COD_(酸化液)=3:2)投加,反硝化滤池出水TN浓度稳定,低于5 mg/L,且出水COD、氨氮达到一级A标准。研究表明,污水处理厂进水中低品质碳源经过水解酸化后产生的VFAs可作为反硝化碳源的补充,实现良好的反硝化处理效果,同时能有效地减少人工碳源的投加使用,削减反硝化滤池工艺运行成本。

In order to meet the requirements of the first grade A standard for discharge quality of sewage water,mainly the total nitrogen(TN),of a wastewater treatment plants(WWTP),denitrification biofilter was carried out to achieve advanced denitrification of secondary effluent.Volatile fatty acids(VFAs)produced by hydrolysis acidification of influent in current WWTP was used as carbon source of denitrification combined with sodium acetate.The results of the pilot test showed that TN of the effluent was lower than5mg/L,and the concentrations of COD,NH3N and TP in the effluents could reach the first grade A standard when the amount of VFAs and sodium acetate was added at the ratio of COD/NO-3N=5∶1(COD sodium acetate∶COD hydrolysis acidification effluent=3∶2).The obtained data indicated that VFAs produced from influent in the hydrolysis and acidification reactors could be used as denitrification carbon source,which was beneficial to reduce commercial carbon source and decrease the operation cost of denitrification filter process.