Design And Realization Of Automatic Control In Wastewater Treatment

Urban wastewater treatment system plays a very important role in solving the problem of water resource shortage and promoting the social sustainable development. There are some problems in urban wastewater treatment plants, such as high operating costs, poor profits, low automatic control level, and so on. Improving the level of wastewater treatment disposal automation and application of advanced control technology are the keys to reduce operating costs and improve production efficiency.Based on the automatic control of Hangzhou Qige project 3, an efficient wastewater treatment auto-control system scheme is designed. This system is integrated by PLC, control servers, field instruments, sensors and many kinds of actuators. Decentralized control, centralized management and information sharing between different departments are realized by using the powerful data acquisition function of PLC, the communication of industrial Ethernet and field-bus, and the powerful image functions of Configuration software. By improving the level of automation equipment and optimizing control process of wastewater treatment, the intensity of work can be reduced and the wastewater treatment efficiency can be improved. Based on the realization of automatic control system, the research of aeration control is going on. By the analysis of the relation of wastewater parameters such as DO, activated sludge microorganisms and substrate, DO is chosen as the controlled object. Fuzzy control system is used as the main control tactics and the simulation results are given based on Matlab.Finally, the process of design, functions implementation and system debug of Qige aeration intelligent control system is introduced. By the analysis of the operating data, we can find that the system can overcome various disturbances, realize DO stability control and reduce the amount of aeration. And the target of energy saving is achieved.