基于溶解氧与需气量串级控制的曝气系统优化控制  

Study on Optimization of Aeration System Based on Cascade Control of DO and Air Demand

作　　者：谢继荣[1] 王佳伟[1] 蒋勇[1] 张志渊[1] 李鑫玮[1] 韩春荣[1] 严彬宾[2] 

机构地区：[1]北京城市排水集团有限责任公司,北京100022 [2]重庆邮电大学自动化学院,重庆400065

出　　处：《中国给水排水》2011年第21期36-39,共4页China Water & Wastewater

基　　金：北京市科技计划项目(D101109047410001);北京市优秀人才培养基金资助项目(PYZZ090428001289)

摘　　要：污水生物处理工艺的高效节能是污水处理厂节能降耗的主要方向。以小红门污水厂的曝气控制系统为例,通过分析原有常规PID曝气控制系统存在的问题,提出了基于溶解氧与需气量串级控制的曝气系统优化控制方法。通过处理规模为15×104 m3/d的工程示范表明,常规PID控制方式对于需气量相对恒定的定常系统具有较好的控制效果,其溶解氧波动范围可以控制在±0.5 mg/L。但当污水处理厂进水负荷波动较大时,溶解氧波动范围超过±2.5 mg/L,并且使阀门等执行机构动作频繁。基于DO与需气量串级控制的曝气优化控制系统提高了系统的快速响应能力和稳定性,能够对需气量发生较大变化的时变系统获得较好的控制效果,其溶解氧的波动范围可以维持在±0.3 mg/L,并进一步提高了节能效果。Biological wastewater treatment process is the most important part for energy saving in wastewater treatment plants （WWTP）. Taking aeration control system in Xiaohongmen WWTP for example, the existing conventional PID control system is analyzed, and an optimized aeration control system based on cascade control of DO and air demand is proposed. The demonstration project with treatment capacity of 15 × 10^4 m^3/d shows that the conventional PID control has good control performance for a fixed system with relatively constant air demand, in which the fluctuation range of dissolved oxygen can be controlled at ± 0.5 mg/L by conventional PID control. However, when the influent loads fluctuate, the fluctuation range of dissolved oxygen is more than ±2.5 mg/L, and the actuating devices （ such as valves） move frequently. The optimized aeration control system based on cascade control of DO and air demand improves the rapid response capability and stability, which can obtain better control performance in the time-varying system with large variation of air demand. The fluctuation range of dissolved oxygen can be maintained at ± 0. 3 mg/L, and the energy saving efficiency can be improved further.

关 键 词：PID控制 串级控制 溶解氧 需气量 时变系统 

分 类 号：X703[环境科学与工程—环境工程]