The Design Of Intelligent Control System In Ultrafiltration And Reverse Osmosis

Thermal power plant is an enterprise in which a large amount of water was used and discharged. Ultrafiltration and reverse osmosis(UF-RO) water treatment technology is applied to thermal power plant wastewater treatment, which can significantly improve the recycling utilization of water, so it not only has the economic efficiency also has a very important social significance.In this paper, the construction and integration of the control system of UF-RO device was completed based on the application project of water treatment in a power plant. The content included the structure design of the control system, hardware selection and configuration of the controller, the control program design and the software design of the upper computer. The control function of the UF-RO water treatment system was realized, such as the manual control of the single step control and the automatic control of whole process and so on. In the control system Siemens S7-400 PLC of redundant configuration was adopted as controller, iFIXI5.0 as PC monitoring system software. An integrated control system of high reliability UF-RO system was designed. The control system was stable and reliable when it was put into operation.The backwashing part of traditional UF-RO water treatment control system was based on the timing(quantitative) backwash mode. Nearly three percent of the water yield was consumed in this method. To solve this problem, the dynamic control strategy of UF-RO membrane backwash time based on the BP neural network algorithm was designed in this paper. The control strategy was running in the upper monitoring computer which can calculate according to the real-time detection of data to determine whether or not to backwash. And the results calculated by monitoring computer were transmitted to the PLC through the industrial Ethernet. Then control program for the backwash of UF-RO was started, and dynamic control of UF-RO membrane cleaning time, mode and intensity was realized.The neural network used in UF-RO water treatment system was analyzed and summarized, proving that the operation efficiency and working life of UF-RO system based on neural network control algorithm were improved.