The Design And Research On The Monitoring And Control System For The Biological Treatment Facility Of Waste Gas

Sewage treatment facilities often discharge harmful waste gas,which contain effiuvial contamination.As the source of stench pollution,sewage treatment facilities have great impact on the surrounding environment and the health of residents.The sewage pumping station in sewage treatment plant is one of the major stench sources. In the process of transporting sewage,a large amount of effluvial and poisonous gas was generated,which has become a public hazard.With the perfection and implementation of the country's environmental laws and regulations,the emissions of stench pollution have been strictly restricted.Deodorization in sewage treatment plants and sewage pumping station has been gradually paid attention.Compared with the traditional methods,biological treatment method has many advantages such as low-cost running,non-secondary pollution.Biological treatment method is a highly efficient technology for controlling air pollution.In order to control the stench pollution in sewage treatment facilities effectively, the paper designed a monitoring and control system to deal with emissions of waste gas,which is based on a combined biological treatment technology.The monitoring and control scheme is composed of upper computer and lower computer.The industrial personal computer(IPC) is used as upper computer.PLC is used as lower computer.The monitoring and control scheme includes the program system of PLC, the supervision system of IPC,and the communication between them.SIEMENS S7-300 PLC is used as lower computer.With the help of the programming software STEP7,the program of PLC is designed to control the process automatically according to the technologic requirements.The IPC is high stable and has a good anti-disturbance performance.WinCC is used to configure the supervisory software,in order to realize the real-time data-logging,supervising and controll,as well as various visual HMI such as technologic flow,record checking,alarming,reporting,parameter setting,real-time curving.The global script of VinCC is used to devise a fuzzy adaptive PID algorithm for the control of circular water's pH in the Bio-trickling filter.PLC and IPC which is in the control room communicate with each other via fieldbus PROFIBUS-DP.The monitoring and control system has fine HMI(Human Machine Interface), simple and convenient operation,and it is reliable,stable and easy to be extended.It not only reflects the on-the-spot working conditions in a direct and vivid way,but also can ensure the stability and precision of the controll parameters.It also can reduce the access of contacting pollution for on-site staff,greatly enhance the level of automation systems,and provide a good condition to realize the goal of enterprise's information management.