琥珀山庄污水处理厂污泥上浮的成因与控制

污水处理厂的污泥上浮会影响污水处理系统的操作、运行和出水水质.活性污泥上浮以后,如不及时处理会造成污泥大量流失、氧化沟内MLSS值降低、微生物量锐减,导致运行彻底失败.本文以合肥市琥珀山庄污水处理厂的工艺运行为实例,寻求活性污泥上浮的原因及其控制对策.通过多年的观察与实践,认为污泥上浮的主要原因有污泥老化与腐化、污泥反硝化、冲击负荷、曝气过度、污泥携油上浮等.实践表明,气温、气压和水温的变化也是污泥上浮的重要原因.常用的控制污泥上浮的方法有增加污泥回流量、及时排除剩余污泥、降低混合液浓度、缩短污泥龄、降低溶解氧、消除沉淀池的死角区、加大池底坡度以及改进池底刮泥设备等.

EXPLORING THE CAUSES AND CONTROL MEASURES TO GET RID OF THE SLUDGE RISING IN THE SEWAGE-DISPOSAL WORKS OF VILLAGE AMBER

The purpose of this paper is to find effective measures to solve the problem of ever rising sludge due to the sewage disposal by taking the sewage disposal Plant Amber Village, Anhui province, for example. When the activated sludge rise, a large part of it on the surface would lose if it were not to be timely treated. At the same time, if the value of MLSS decreases in oxidation, the quantity of microorganism would quickly and sharply decrease, which may lead to the total failure of microorganism recycling. This paper takes the operation system of the Amber Village Sewage Plant of Hefei, as an example to search for the cause and countermeasure so as to be able to control the sludge rising problem. Through our years' observation and practice, this paper has summarized the main causes leading to the rising of activated sludge in the following six points: aging and septicity, sludge reverse nitrification, impact loading, over aeration, and sludge rising due to the increase of grease. Our findings suggest that temperature change, the change of air pressure and water also account for the sludge rising. Our practice also shows that the common methods of controlling sludge rising can be summarized as follows: to increase the sludge return value; to get rid of excessive sludge timely; to lower the concentration of mixed liquor; to shorten the sludge age; to reduce the dissolved oxygen, etc. Effective measures may also include eliminating of the dead corner of sedimentation tank, enlarging the bottom grade of the tank and improving the scrape facility, etc. In autumn and winter seasons, sludge rising may be caused by not degradation of some synthetic detergent, grease accumulation out of the domestic sewage as well as soil impurities.