A/A/O工艺运行过程中磷的迁移与积累规律

Analysis on removing and accumulating approach of phosphorus in A/A/O technology

摘要:

为提高污水处理厂科学运行管理水平和出水质量,通过对北京某污水处理厂污水处理工艺的沿程采样分析,研究A/A/O工艺运行过程中磷的迁移途径、除磷效率与工艺运行控制参数之间的相关性,并进行污水处理系统内部磷平衡核算.结果表明,A/A/O工艺缺氧段存在明显的反硝化聚磷作用,其吸磷量超过好氧段的,回流硝化液中硝酸盐质量浓度对反硝化聚磷作用有影响;除磷效果与污泥负荷、泥龄呈反向变化趋势,当污泥负荷控制在0.15 kg/(kg.d)左右,泥龄控制在10～12 d时,除磷效率在88%左右;污水处理系统内部磷的积累与排泥量具有显著的反向相关关系,排泥量控制在进水量的2.0%～2.5%时,可以保持系统稳定除磷状态,同时可避免过量排泥造成的经济浪费.

Abstract:

To improve the scientific management level and effluent quality of a municipal wastewater treatment plant(WWTP),the relationship between the phosphorus removal approach and operating parameters of the A/A/O technology was analyzed by sampling and analyzing samples from the treatment technology process of a WWTP in Beijing,and also the phosphorus material balance was assessed for the sewage treatment system.The results showed that the denitrifying phosphorus removal played remarkably a role for phosphorus removal in the anoxic zone of A/A/O process.The absorption of phosphorus in anoxic zone had exceeded the quantity in the oxic zone.The nitrate concentration in the returned nitrifying liquid had an influence on the denitrifying phosphorus removal.The relationship between phosphorus removal and sludge load,sludge retain time(SRT) showed negative correlation.When the sludge load was about 0.15 kg/(kg·d)and the SRT was about 10-12 d in A/A/O process,the phosphorus removal rate was up to 88%.There was also a negative correlation relationship between the phosphorus accumulation and the sludge emission capacities in the wastewater treatment system.When the sludge emission capacities were controlled to 2.0-2.5 percent inflow of the treatment plant,the phosphorus removal efficiency could be kept on stable and economic status.