Design of distributed control system for wiped film molecular distillation

The wiped film molecular distillation is a molecular still with a rotating scraped film structure, which has the advantages of fast separation and high purity. In this paper, Distributed Control System (DCS) is used to automate the control of the film evaporation process, and establish the control master and slave station. The speed of the feed motor, the speed of the film motor, the temperature of the thermostat and the hot oil machine in the two-stage distillation process are detected and controlled by two circuits in the film scraper evaporator. The hardware of the distributed system is configured and programmed by the STEP7 of SIMATIC to control the process of film evaporation. Then use configuration software designs a monitoring interface for the two-stage distillation process, which is convenient to record real-time data, realize remote safety control of the film scraping evaporation process.