活性污泥法单级自养脱氮工艺的启动及污泥特性

Study on Start-up and Sludge Properties of CANON Process with Activated Sludge

在SBR反应器内，先后接种普通活性污泥及少量具有单级自养脱氮能力的生物膜，在温度为（32±1）oC、pH值为7．5～8．5的条件下，进行了活性污泥法单级自养脱氮工艺的启动及污泥特性研究。SBR首先接种活性污泥，采用控制较高游离氨浓度（5．75～8．97mg／L）及较低DO值（0．17mg／L）的方法，经过50d实现了短程硝化，亚硝酸盐氮积累率在80％以上；然后采用进一步降低DO值、以清水置换SBR内剩余出水及改连续曝气为间歇曝气等方法，尝试在SBR内富集厌氧氨氧化菌，但过程缓慢；当接种0．15g单级自养脱氮生物膜后，很快建立了厌氧氨氧化与亚硝化的协同作用，23d后，对TN的去除率及去除负荷分别达到83．07％及0．422kgN/（m^3·d）。镜检发现SBR内为活性污泥絮体与颗粒污泥的混合物，经激光粒度仪测定，絮体污泥粒径为1～300μm，颗粒污泥粒径在300—1800μm，两者的体积比约为7：3。

Start-up and sludge properties of the completely autotrophic nitrogen removal over nitrite （CANON） process were studied in the SBR with activated sludge and CANON biofilm as seeding sludge at the temperature of （32±1 ）℃ and pH of 7.5 to 8.5. The short-cut nitrification was realized by con- trolling free ammonia at 5.75 to 8.97 mg/L and DO at 0.17 mg/L for 50 d, and the nitrite accumulation rate was over 80%. The anaerobic ammonium oxidation （ANAMMOX） bacteria were cultivated by re- ducing the DO value, replacing the residual water in SBR with tap water and turning continuous aeration into intermittent aeration. But the course was very slow. After 0.15 g of CANON biofilm was inoculated in the SBR, the synergy between ANAMMOX and nitrosation was established. The removal rate and load- ing rate of TN were 83.07% and 0. 422 kgN/（m3·d） respectively after cultivating for 23 d. Activated sludge and granule sludge were found mixed in the SBR through microscopic examination. The analysis result of the laser particle analyzer showed that the volume ratio of activated sludge with size of 1 to 300μm to granular sludge with size of 300 to 1 800μm was 7 ： 3.