两级A/O生物滤池处理生活污水的挂膜启动研究

Study on the start-up of membranes for domestic sewage treatment by two-stage A/O biofilter

采用低碳氮比生活污水,研究了两级A/O生物滤池的挂膜启动及其对COD、NH+4-N的去除性能。结果表明:①试验对陶粒为载体的两级A/O生物滤池进行挂膜启动,在流量分配比、水力负荷、DO分别为50%∶50%、0.7 m 3/(m 2·h)、4 mg/L的工况下,反应器采用“快速排泥法”历时57 d挂膜完成;②COD去除率在第51 d达到66%,NH+4-N去除率在第49 d达到80%并保持稳定,出水水质均达到GB 18918—2002《城镇污水处理厂污染物排放标准》一级A标准;③挂膜完成时,镜检可见反应器填料上附着大量菌胶团以及轮虫、钟虫等微生物,电镜扫描也观察到白色条带和斑点,均表明挂膜启动成功。

The low-carbon-nitrogen ratio domestic sewage was used to study the membrane initiation of the two-stage A/O biofilter and its removal performance for COD and NH+4-N.The results showed that:(1)The test was carried out on the two-stage A/O biofilter with ceramsite as carrier.The“fast sludge removal method”was adopted,and the reactor membrane start-up process lasted for 57 d with the flow distribution ratio,hydraulic load and DO were 50%∶50%,0.7 m 3/(m 2·h),and 4 mg/L,respectively;(2)The COD removal rate reached to 66%on the 51 d,and the NH+4-N removal rate reached to 80%on the 49 d and remained stable,the effluent quality reached the first-class A standard of the Emission Standards for Pollutants in Urban Sewage Treatment Plants(GB 18918—2002);(3)When the film was completed,microscopic examination showed that a large number of bacterial micelles and microorganisms such as rotifers and bell worms were attached to the reactor and white bands and spots was observed on electron microscopy,indicating that the film was successfully activated.