Research On Preparation And Purification System Of Artificial Seawater

This thesis designed an artificial seawater preparation and purification treatment system,which is used in the field of experimental research on electrical field characteristics of the ocean environment.It is mainly composed of a device preparing seawater and a treatment system purifying the artificial seawater.This thesis applied the programmable control technology and human-machine interface technology to form a mechatronic integration of seawater preparation device,which made use of a PLC and a water level automatic control system with water level sensors in the test pool and mixing tank.The device can automatically control the circulating pumps,the electrical actuators and solenoids in and out of operation according to the water level,salinity,and process control diagram preset by PLC and HMI,in order to ensure the continuous preparation of artificial seawater in accordance with the design requirements and maintain the best state of being efficient and reliable.In the preparation process,the salinity of artificial seawater can be precisely controlled by means of precisely measuring how much water and salt have been used,in order to indirectly realize the design requirement of the conductivity of artificial seawater.In addition,in order to ensure the quality of the artificial seawater,this thesis designed a seawater purification treatment system,which can monitor the purification quality of seawater,can adjust the ORP value by adding disinfection solution,can regulate the pH value by adding acid or alkali,can filter the impurities and sludge in the pool by means of the front and rear sand filter,and can kill harmful bacteria by using the odor sterilization device and ultraviolet disinfection device.Finally,this thesis designed the PLC program and the HMI interface of the control system,and carried out the software debugging and system alignment testing,which shows that all functions of control and process diagram have been realized and the design requirement of specification for the system has been satisfied.