高效絮凝工艺深度处理污水厂出水的中试研究

PILOT STUDY ON ADVANCED TREATMENT OF MUNICIPAL WASTEWATER USING HIGH EFFECTIVE FLOCCULATION CRAFT

为了使沈阳北部污水厂二级出水达到回用水质,在中试条件下采用污泥回流高效絮凝工艺对其进行深度处理。实验中优化了高效絮凝工艺中的反应强度(G值)、污泥回流比、混凝剂和助凝剂的投药量等工艺运行参数;并考察各种运行条件下的处理效果。实验结果表明,采用污泥回流高效絮凝工艺处理沈阳北部污水厂二级出水效果良好,出水COD≤30 mg/L、浊度≤0.9 NTU、色度≤29度、ρ(TP)≤1 mg/L、ρ(NH3-N)≤10 mg/L,均达到了回用标准。中试条件下的最佳运行参数:污泥回流量在低温低浊工况下为40 L/h,在常温常浊工况下为30 L/h;G值为18.9 s-1;PAC投加量30 mg/L;助凝剂阳离子PAM RT 2300投加量0.45 mg/L。

In order to ensure the quality of second-class effluent in Shenyang north sewage treatment plant meet the level of water quality standard for the reuse of recycling water, the high effective flocculation craft was used for advanced treatment of this effluent in a pilot-scale test. The reacting intensity （G value）, sludge return ratio, coagulant and coagulant aid dosage of the high effective flocculation system were optimized, and the treatment effect of the system under different conditions was also investigated. The results show that, the high effective flocculation craft applied in the treatment of the second-class effluent from Shenyang north sewage treatment plant is effective. After treated by high effective flocculation craft, the effluent quality was reaching the expected target： COD ≤30 mg/L, turbidity ≤0.9 NTU, chroma ≤29, p（TP）≤ 1 mg/L, and p（NH3-N）≤10 mg/L. The optimal operation parameters in the pilot-scale test are as follows： sludge recycle flow rate at low temperaatre and low turbidity conditions for 40 L/h, in normal temperature and turbidity conditions for 30 L/h, G value is 18.9 s^-1, the dosage of PAC was 30 mg/L, and the coagulant cationic PAM RT 2300 dosage is 0.45 mg/L.