Research On Reverse Osmosis Membrane Water Purification Control System

At present,the reverse osmosis membrane water purification control system still has the disadvantages of acquiring few types of water quality parameters,no strict restrictions on the quality of membrane-entering water,and the inability to achieve predictive control.Aiming at the above problems,micro-control system technology,sensor technology and communication technology are combined in this paper to study a reverse osmosis membrane water purification control system.Temperature,conductivity,pressure,turbidity,flow and other parameters are comprehensively collected by the system.The control system will automatically alarm when the quality of membrane-entering water does not reach the preset target.At the same time,a water production rate prediction model is established by the system and the remaining life of the reverse osmosis membrane is predicted based on the decline trend of the water production rate.STC15W4K56S4 is used as the main control processor of the control system.The main control processor,relay drive unit,parameter acquisition unit,peripheral circuit,and DTU constitute the system's lower computer,which realizes parameter acquisition,pump/valve drive,data storage,MCU monitoring,real-time Clock,serial communication and other functions.The water purification site PC and the user's mobile phone/PC are included in the upper computer,which realizes the functions of parameter viewing,threshold modification,pump/valve control,log viewing,and automatic alarm.The PC on the water purification site communicates with the lower computer through the serial port,the user's mobile phone/PC communicate with the lower computer access the cloud server through the Internet.The data of the cloud server is provided by DTU through the 4G network.In addition,the remaining life prediction algorithm of reverse osmosis membrane is studied in this paper.The control system bases on the existing historical water production rate within 517 days to fill in the original data set,fills in missing values,replaces outliers,smooths data noise,establishes a water production rate prediction model and evaluates the reaction based on the water production rate.In the working state of the osmosis membrane,an alarm is issued in advance when the reverse osmosis membrane is about to reach the maximum service life,which realizes the prediction of the remaining life of the reverse osmosis membrane.The main program of the system is designed according to the process flow of reverse osmosis membrane water purification,he PID automatic dosing program and the remaining life prediction program of the reverse osmosis membrane are designed.The entire control system is tested and the test result has met the requirement of the control system.