以城市污水处理厂剩余污泥为种泥,以2 min沉淀时间为选择压,在序批式反应器(SBR)中快速培养出好氧颗粒污泥。经过60个周期(20 d),反应器内出现砂粒状颗粒,并持续稳定运行120 d。成熟的颗粒污泥平均粒径856.56μm,具有良好的硝化性能。SBR反应器以固定曝气时间方式运行,亚硝酸盐积累率达80%以上,实现了稳定短程硝化。试验结果表明:絮体污泥(即接种污泥)与颗粒污泥的硝化过程相似但略有差异。二者差别在于,氨氮氧化结束后,继续曝气120 min,絮体污泥将亚硝酸盐完全转化为硝酸盐,而颗粒污泥仅将部分亚硝酸盐转化且过程比较缓慢。
Taking the waste sludge gained from municipal wastewater treatment plants as seed sludge,aerobic granular sludge was rapidly cultured in a sequencing batch reactor through the selection pressure formed by 2 min settling time.Granular sludge in shape of sand appreaed in the 60th circle(20 d),and was operated for 120 d.The formed granular sludge has an average diameter of 856.85 μm,which has a good nitrification performance.A steady partial nitrification was achieved in the sequencing batch reactor that operated in an fixed aeration time,the nitrite accumulation rate(NO2-N / NOx-N) was over 80%.The result of batch test indicated that the nitrification processes of flocs sludge and granular sludge were similar but had a diffierence.The difference was that a continuous 120 min aeration after the end of ammonia oxidation,the flocs sludge would convert nitrite to nitrate completely,however,the procedure of granular was very slow and only a small part of nitrite was converted.