Sewage Treatment Control System Based On A~2O Process Research

With the progress and development of human society,natural resources reduces gradually,especially the serious shortage of water resources,the water environment protection is very important.Although the sewage treatment process guarantee the water quality,the requires of the water quality promote the water treatment technology,especially automation and intelligence.This thesis studied the Harbin Acheng sewage treatment plant,introduced A2 O technology on the base of sewage treatment and process,and accomplished a automation system design and engineering realization for a sewage treatment plant.The thesis analyzed the simplified model of urban wastewater biochemical treatment process,and studied the steady state and dynamic response with the simulation.For the shortcoming of high power consumption,the paper studied an overall optimal control system.For the oxygen control and the turbidity control,the thesis studied the dynamic models and simulation.For the disturbance in the turbidity control system,the thesis presented a feedforward-feedback algorithm in order to shorten the response time.For the delay problem in the oxygen control system,the thesis compared the Smith estimation and the Dalin method,and shorten the response time by using Smith estimation-PID controller.The numerical dissolved oxygen concentration and sludge discharge as decision variables,the number of complete optimization control model is established,so as to realize the optimal control of the sewage treatment process.The thesis designed an automatic control system by using PLC controller,the system includes sludge treatment control subsystem,blower room control subsystem,the pretreatment control subsystem,air compressor control subsystem,and dosing pump control subsystem.Industrial Ethernet is used to connect subsytems and transfer the data in order to control and monitor the working state of each part.In order to realize the automation of the sewage treatment.