城镇污水处理厂除磷影响因素及优化运行研究

随着全国重点流域城镇污水处理厂迎来新一轮提标改造，其中部分污水处理厂对出水总磷（TP）的排放限值由0.5 mg/L降低为0.3 mg/L，甚至降至0.2 mg/L，这对城镇污水处理厂除磷提出了新的挑战。通过对全国58座执行GB 18918-2002《城镇污水处理厂污染物排放标准》一级A标准的城镇污水处理厂进行调研分析，探讨了目前污水处理厂在实际生产运行中除磷存在的主要问题并给出相应对策，为今后高TP标准排放下污水处理厂的运行管理提供技术指导。调研结果表明:各污水处理厂的释磷潜力为0.01~23.98 mg/（g·h），其平均值为2.77 mg/（g·h），释磷潜力普遍较弱。生物除磷效果较差的主要原因为进水碳源不足、厌氧区存在高浓度硝态氮及同步化学除磷的抑制作用。基于上述调查分析，有针对性地提出了具体的调控措施，并建议污水处理厂要根据进水水质情况，通过静态实验确定最佳除磷药剂种类及合适的投加量，有效控制化学除磷过程，从而达到节省药耗的目的。

THE INFLUENCING FACTORS AND OPTIMAL OPERATION OF PHOSPHORUS REMOVAL IN URBAN WASTEWATER TREATMENT PLANTS

With the new round upgrading of urban sewage treatment plants in key river basins across China, some sewage treatment plants reduced their total effluent (TP) emission limit from 0.5 mg/L to 0.3 mg/L, and even to 0.2 mg/L, which posed a new challenge for phosphorus removal in urban sewage treatment plants. In this paper, by investigating and analyzing 58 urban sewage treatment plants that implement the Grade I-A Discharge Standard in China's national standard GB 18918-2002, we discussed the main problems of phosphorus removal in the actual production and operation of sewage treatment plants and gave corresponding countermeasures for future high-standard TP emissions, in order to provide technical guidance for the operation and management of the sewage treatment plant. The survey results showed that the phosphorus release potential of each sewage treatment plant was in the range of 0.01~23.98 mg/(g·h), and the average phosphorus release potential was 2.77 mg/(g·h). The phosphorus release potential was generally weak; insufficient carbon source in the feedwater, high concentration of nitrate nitrogen in the anaerobic zone, and the inhibition of simultaneous chemical phosphorus removal were the main reasons for the poor biological phosphorus removal effect, and specific control measures were proposed accordingly. In addition, it was recommended that the sewage treatment plant determined the best phosphorus removal agents and appropriate dosage by static experiments according to the quality of the incoming water, so as to achieve more reasonable control of the chemical phosphorus removal process, thereby achieving the purpose of saving phosphorus removal agents consumption.