SBR法处理生活污水时非丝状菌污泥膨胀的发生与控制

采用序批式活性污泥法(SBR)处理实际生活污水.研究了低溶解氧条件下,有机负荷对污泥膨胀的影响和突然降温对污泥沉降性能的影响.低溶解氧条件下,当有机负荷为0 20kg·(kg·d)-1和0 26kg·(kg·d)-1时,活性污泥中虽然有丝状菌存在,但并没有发生污泥膨胀.有机负荷达到0 57kg·(kg·d)-1时,菌胶团过量生长,发生非丝状菌污泥膨胀.提高溶解氧,降低有机负荷可使污泥沉降性能恢复正常.突然降温,也会导致非丝状菌污泥膨胀.恢复温度后,膨胀现象可得到控制.非丝状菌污泥膨胀除了没有丝状菌过量增殖外,还具有污泥有粘性,泥水混合液难过滤的特点.

Non-filamentousactivated sludge bulking in SBR treating the domestic wastewater

The effects of sludge loads under low DO condition and temperatures on activated sludge settle ability in a Sequencing Batch Reactor (SBR) fed with domestic wastewater were investigated. Though the system was kept in low DO levels, the sludge settled properly at sludge load of 0.20kg·(kg·d)-1and 0.26kg·(kg·d)-1, respectively. Deterioration of SVIs was observed after increasing sludge load to 0.57kg·(kg·d)-1, which was related to the excessive growth of Zoogloea colonies. Through increasing DO and decreasing sludge load, the zoogloea flocs gradually changed to the well-settling sludge. The non-filamentous activated sludge bulking also occurred when the temperature was decreased sharply. After increasing the temperature to the original level, the sludge bulking was controlled effectively and the low SVI was recovered. When the non-filamentous activated sludge bulking occurred, the sludge had a jelly like viscous consistency and became hard to filter.