低温优选模式下CAST工艺DO和MLSS的优化  

Optimization DO and MLSS of CAST Process under Low Temperature and Optimal Mode Conditions

作　　者：吴磊[1,2] 龙天渝[1,2] 王俊 

机构地区：[1]重庆大学三峡库区生态环境教育部重点实验室,重庆400045 [2]重庆大学城市建设与环境工程学院,重庆400045 [3]武汉市东西湖自来水公司,湖北武汉430040

出　　处：《中国给水排水》2011年第13期29-32,共4页China Water & Wastewater

基　　金：国家水体污染控制与治理科技重大专项(2009ZX07104-002);中国科学院西部行动计划项目(KZCX2-XB2-07)

摘　　要：根据万盛污水处理厂在冬季低温下运行时出水NH3-N和TN浓度超标现象较为严重的情况,为了强化CAST工艺的脱氮效果,在已确定的优选C运行模式即进水2 h—曝气2.5 h(进水1.5 h后开始曝气)—沉淀1 h—滗水/待机1 h的基础上,分别进行了DO和MLSS两个运行参数优化的研究。在基本运行参数保持不变的情况下,通过分析不同DO和MLSS值时的除污效果,确定了低温期的DO最佳控制阈值为2.0～3.0 mg/L,MLSS最佳控制阈值为5 000～6 000 mg/L。优化运行参数后,系统对COD、NH3-N、TN的平均去除率分别为91.2%、83.2%和69.4%,脱氮性能得到明显提升。According to the effluent NH3 - N and TN exceeding the standard in Wansheng WWTP operated at low temperature in winter, the two operating parameters of DO and MLSS were respectively optimized based on the C preferred operation mode, namely influent 2 h, aeration 2.5 h （ aeration after influent 1.5 h）, sedimentation 1 h and decanting/standby ! h in order to enhance nitrogen removal effect of CAST process. When the basic operating parameters are unchanged, through analyzing the pollutant removal efficiency at different concentrations of DO and MLSS, the optimal control thresholds of DO and MLSS are determined as 2.0 to 3.0 mg/L and 5 000 to 6 000 mg/L respectively during low temperature period. After optimization of running parameters, the average removal rates of COD, NH3 - N and TN are 91.2%, 83.2% and 69.4% respectively, nitrogen removal performance of the system is improved significantly.

关 键 词：CAST工艺 脱氮 低温 参数优化 

分 类 号：X703[环境科学与工程—环境工程]