Research On Control System For Municipal Wastewater Treatment

Purging the sewage is very important for our living and producting. It's also essential to our goal of development which is continuable.In this thesis, the distributed control system(DCS) for wastewater treatment was designed with research of municipal wastewater treatment technics. The control system consists of industrial person computer(IPC),PLC control system and local intelligent control instruments, etc. The DCS system implements distributed control and centralized supervision in wastewater treatment.The industrial computer mainly implements the functions of supervision and management. It includes: dynamic show of technics flow, real time data acquirement and show, history data save and print, fault alarm, etc. The PLC control system mainly accomplishes the wastewater technics flow control, harmonizes the logical relationship among local intelligent control instruments and transmits the state of each local equipment to the industrial computer simultaneously, the PLC control station receives the control commands from the industrial computer; The local intelligent units take charge of the correlated parameters measure, disposal and control, and it will transmit the related parameters to the computer, etc.In this thesis, introduced municipal wastewater treatment technics, the integrated application program development of computer, the design method of PLC control station, the communication between PLC control system and computer, and the network of wastewater treatment with profibus-dp was also discussed.The dissolved oxygen (DO) is one of the most crucial parameter in municipal wastewater treatment system. DO is choosed as the control object and DO control system from theory...