The Research And Development Of The Integrated Automation System Of Bromine

Bromine products have a very wide application in the field of medicine, pesticide, dye application and various fields of industry. China’s coastal bromine manufacturers use air blowing method to extract bromine from seawater. Because of the corrosive environment and process medium, it is difficult to choose detecting instrument and actuator valve instrument. As the manual operation, there is a need to improve the automation level.According to the process and security requirements, this paper builds an automatic monitoring system platform based on Industrial Ethernet, fieldbus technology and other network system. DCS control method has a S7-300CPU315-2DP as the main station and double CPU software redundancy. Most of the variables of detection and control process are completed by the master. Via the Profibus-DP bus, the S7-300 master is connected to the three sub control station, which is responsible for the bittern pump frequency converter station, sulphur burning station and weighing the alarm data collection and control station. This paper completes the selection of PLC type and its extension module also display instrument, fills the automatic control equipment table, draws the detecting process of the electrical wiring diagram and controls flow diagram and makes upper unit state picture through the PC configuration software KingView6.55.In the monitoring system platform, in view of blowing out with acid, this paper uses the integral separation PID to add acid with the PH value automaticly. In view of blowing out with chlorine, this paper uses fuzzy self-adjust PID to add chlorine with ORP value. Because of the adsorption properties of ORP electrode, here uses constant acid, constant temperature and self-cleaning technology to ensure the accurate measurement of ORP. In view of distillating with chlorine, this paper uses cascade ratio control. Main controller is the bromide composition controller, sub control is single ratio control to complete the fluid flow and chlorine flow rate, operating variables is the chlorine dosage, by adjusting the chlorine dosage to maintain stable component of bromide. As the bromine ingredients are difficult to measure online, here uses image analysis technology. Control procedures are programmed using SIEMENS STEP7V5.5 software. Monitor screens are made through the PC configuration software KingView6.55.The system realizes the automatic control of key variables to blow out and distillation. It makes human-computer isolation real, ensuring personal and equipment safety. Also, with simple system operation, the level of the automatic control is highly improved, obtaining obvious economic benefit and social benefit.