改良型UCT工艺在农村生活污水处理中的应用

Application of modified UCT process in decentralized rural sewage treatment

我国农村生活污水处理设施的进水COD往往低于设计水质,因而脱氮除磷过程中碳源不足,同时进水中TN、TP波动较大,导致现有工艺难以稳定实现脱氮除磷。针对这一问题,构建了基于改良型UCT工艺的一体化农村生活污水处理系统,并应用在江苏省常州市某村落。该处理系统可使污泥脱氮与混合液脱氮实现分离,在保证脱氮效率的同时,进一步减少硝酸盐进入厌氧区,以保证稳定的脱氮除磷效果。该系统已稳定运行超过2年,对COD、NH3-N、TN、TP等指标的平均去除率分别为87.8%、94.5%、72.9%和83.9%,出水水质满足江苏省《村庄生活污水治理水污染物排放标准》(DB32/T 3462-2018)中一级A标准。本案例可为我国农村生活污水处理的技术选择和运行提供参考。

The COD concentration of most domestic rural sewage is lower than that of the design influent,leading to insufficient carbon source in the removal of nitrogen and phosphorus.Besides,the TN and TP concentration of the influent sewage fluctuate greatly,which makes it difficult for existing technologies to achieve stable removal effect of phosphorus and nitrogen.Based on the modified UCT process,an integrated rural sewage treatment system was developed and applied in Changzhou City,Jiangsu Province.The system can completely separate the denitrification of the sludge and that of the mixture,ensuring the efficiency of denitrification and further reducing the amount of nitrate entering the anaerobic zone.The system has been operated stably for over two years.The average removal efficiencies of COD,NH3-N,TN and TP were 87.8%,94.5%,72.9%and 83.9%,respectively,and the effluent met with the ClassⅠ-A standard according to the Discharge standard of water pollutantsfor rural domestic sewage treatment(DB32/T 3462—2018).The case study can provide a reference for technology selection and operation of rural decentralized sewage treatment.