城镇污水处理厂供氧效率和运行能耗监测评估与优化  

Monitoring,evaluation and optimization of energy consumption and oxygen transfer efficiency in municipal wastewater treatment plant

作　　者：刘战广 LIU Zhanguang(Shajighai Municipal Engineering Design Institute(Group)Co.,Ltd.,Shanghai 200092,China)

机构地区：[1]上海市政工程设计研究总院(集团)有限公司,上海200092

出　　处：《给水排水》2021年第7期32-37,共6页Water & Wastewater Engineering

基　　金：上海市青年科技启明星计划资助(18QB1403600);上海市科委“科技创新行动计划”项目(18DZ1203804)。

摘　　要：城镇污水处理是能耗密集型行业,能耗在线监测、定量分析与定向优化是降低运行成本的重要途径。通过智能电表、电量采集器等进行能耗在线采集和定量分析,并采用脱气法监测曝气系统氧转移效率(OTE),结果表明:生化处理段是最大用电工艺单元,其能耗占总能耗的50%以上。曝气、提升、搅拌、紫外消毒等设备用电量占总用电量的90%以上。基于能效评估更换部分曝气设备,优化曝气系统和机械搅拌运行方案,OTE最大值从15%-20%提升至25%-28%,污水处理厂单位电耗从0.38kW·h/m^(3)降至0.30-0.31kW·h/m^(3)。OTE和DO之间关联性较高,CASS工艺曝气周期中,OTE迅速上升并维持在较高水平,随着耗氧污染物的降解,OTE逐渐下降,DO逐渐上升。曝气周期后期,OTE显著降低且DO高于设定值时,可能出现曝气过度。Municipal wastewater treatment is an energy-intensive industry,and the online monitoring,quantitative assessment and targeted optimization of energy consumption are important ways to reduce cost and improve operation.The smart electricity meters and electricity collectors have been applied to collect electricity online for quantitative analysis of operational energy consumption and energy consumption distribution.The oxygen transfer efficiency(OTE)of the aeration system has also been measured and evaluated using off-gas method.The results show that the secondary biological treatment is the largest energy consumption section and it accounts for above 50%of the total energy consumption.The electricity consumption of aeration system,lifting pumps,mixers and UV disinfection equipment accounts for above 90%of the total electricity consumption.Based on the evaluation of energy efficiency,some aerators and air supply pipes were replaced,and the operation plan of aeration system,mixers and other equipment was optimized accordingly.With these energy-saving measures,the maximum OTE increased from 15%-20%to25%-28%,and the specific electricity consumption of the municipal wastewater treatment plant declined from 0.38 kW·h/m^(3) to 0.30-0.31 kW·h/m^(3).There is a high correlation between OTE and dissolved oxygen(DO).During the aeration cycle of the CASS process,OTE rises rapidly and maintains at a high level.With the degradation of oxygen-consuming pollutants,OTE gradually decreases,and DO gradually increases.At the end of the aeration cycle,when OTE is significantly reduced and DO is higher than the set value,over-aeration may occur,indicating an energy-saving potential.

关 键 词：污水处理厂 能耗 氧转移效率 监测 运行优化 

分 类 号：TU992[建筑科学—市政工程] X703[环境科学与工程—环境工程]