多点进水多级AO工艺在寒冷地区大型污水处理厂的应用

Application of Step-Feed Multi-Stage AO Process in Large WWTPs in Cold Region

为进一步提升生态环境和水环境质量,提升公众满意度,唐山市中心城区现状的3座污水厂需进行迁建,在郊区新建2座大型规模的污水厂,同时出水标准提升到“准Ⅳ类”水(除TN外,其余指标均达到地表水Ⅳ类标准),可为周边用户提供再生水资源。唐山位于寒冷地区,冬季温度较低时,污水厂在生物反应阶段的脱氮除磷效果明显下降。多点进水多级AO生物处理工艺具有较强的灵活性、适应性和耐冲击负荷能力,在进水水质变化时,能增强系统运行稳定性,保证污水厂平稳运行,有利于污水厂对维护良好水环境做出保障,同时为城市提供稳定的再生水资源。该工艺可以充分利用污水自身所含营养物质,优化分配污水中的碳源,并对污水中的氧和磷进行精准的脱离,从而达到节约能耗、降低处理成本的目的,经济效益良好。按30万m^(3)/d的污水处理规模计算,全年可节约电费约为131万元,乙酸钠药剂费约为1944万元。

In order to further improve the ecological environment and water environment quality,enhance public satisfaction,three existing wastewater treatment plants(WWTPs)in the original central city of Tangshan are relocated and two large WWTPs are built in the suburbs.At the same time,the effluent standard reaches“quasi-classⅣ”water(except TN,other indices meet the classⅣstandard for surface water),and renewable water resources could be provided for surrounding users.Tangshan is located in a cold area with low temperature in winter.The effect of nitrogen and phosphorus removal in the biological reaction stage of WWTP is not ideal.Step-feed multi-stage AO process has strong flexibility,adaptability and impact load resistance.When the influent water quality changes,it can maintain the stable and reliable operation of the system,ensure the smooth operation of the WWTPs,be beneficial for the WWTP to ensure the maintenance of a good water environment,improve the quality of water ecological environment,promote the construction of ecological civilization,and provide stable renewable water resources for the city.The process can make full use of the nutrients of wastewater,optimize the distribution of carbon source in wastewater,accurately use the carbon source for nitrogen and phosphorus removal,save the operation energy consumption of WWTPs,reduce the energy consumption and operation cost of WWTPs,and have good economic benefits.According to the wastewater treatment scale of 300000 m^(3)/d,the annual electricity cost can be saved about 1.31 million yuan,sodium acetate drug cost can be saved about 19.44 million yuan.