摘要：

污泥黏性膨胀问题一直是A²O工艺运行控制的难点。郑州市某污水处理厂在运行过程中出现污泥黏性膨胀问题，造成污泥沉降性能变差，SVI逐渐提升至240 mL/g左右，二沉池泥位持续升高。从进水水质、水温、曝气量、浮渣等多方面综合分析引起污泥膨胀的原因，及时从剩余污泥排放量、污泥龄、溶解氧、回流比、水力停留时间等工艺参数调整运行工艺，使污泥膨胀问题得到一定程度的缓解。为彻底消除生物池浮泥，又通过在二沉池配水井精准投加40 mg/L的阳离子高分子絮凝剂，经过一段时间的药剂助沉，明显提高了污泥沉降性能，SVI也逐渐下降至120 mL/g左右的正常水平，解决了污泥黏性膨胀问题，消除了生物池浮泥，为解决污泥黏性膨胀提供了思路。

关键词: A²O工艺, 污泥黏性膨胀, 生物浮泥, 絮凝剂

Abstract:

Sludge viscosity expansion has always been a difficulty in the operation control of A²O process. The sludge viscosity expansion problem occurred in a sewage treatment plant in Zhengzhou City, resulting in poor sludge settling performance with SVI gradually increasing to about 240 mL/g and the mud level of the secondary sedimentation tank continuing to rise. The reasons of sludge swelling were analyzed from the aspects of inlet water quality, water temperature, aeration rate and scum. And then some measures such as adjusting the residual sludge discharge, sludge age, dissolved oxygen value, reflux ratio, hydraulic residence time were timely adopted, so that the sludge bulking problem was alleviated to a certain extent. In order to eliminate the floating mud in the biological tank, 40 mg/L cationic polymer flocculant was added to the distribution well of the secondary sedimentation tank. After a period of time, the sedimentation performance of the sludge was obviously improved with the SVI gradually decreasing to the normal level of about 120 mL/g, indicating that the problem of sludge viscosity swelling and eliminated the floating mud in the biological tank was solved. It provides a way to solve the viscous swelling of sludge.

Key words: A²O process, sludge viscous bulking, biological floating mud, flocculant

中图分类号: 

• X703.1