The Design Of Sewage Treatment Control System Based On PLC

With the development of the economy,people's living standards are getting higher and higher,and the scale of cities continues to expand,resulting in more and more serious water pollution problems.In view of the environmental problems caused by water pollution,there is an urgent need to study a set of efficient,safe and stable sewage treatment control system.According to the requirements of sewage treatment,the three stages of sewage treatment are analyzed,and a set of sewage treatment control system using constant water level SBR process for domestic sewage is designed.Chooses Siemens S7-300 PLC as the control master station,ET200 M and G120 frequency converters as the control slave stations,the communication between the master and slave stations adopts PROFIBUS-DP network,forming a distributed I / O control system;the upper computer chooses Siemens industrial control The communication between the upper computer and the lower computer adopts PROFINET network,which can realize the rapid communication between the upper computer and the lower computer.In the software design,the monitoring part selects the WinCC configuration software to construct the monitoring screen of the host computer;the hardware configuration and control program part uses TIA Portal software to configure the system hardware,and writes the PLC control program for each control link.Aiming at the problem that it is difficult to accurately control the dissolved oxygen concentration of sewage in the aeration process of traditional sewage treatment,a fuzzy adaptive PID algorithm is proposed to control the speed of the fan,so as to achieve precise control of the dissolved oxygen concentration.The design of the automatic wastewater treatment control system combines the latest PLC control technology with the latest wastewater treatment process to achieve automatic control of the whole wastewater treatment process,and can monitor the operation status of each link in real time,can find faults in time and deal with,stable,High efficiency,energy saving,perfectly meet the requirements of sewage treatment.