Abstract
Three control schemes based on temperature, pressure and temperature, and ratio were proposed for hybrid distillation-vapor permeation process of ethylene/ethane separation. The dynamic performances of the three control strategies were examined based on the responses to step changes of the flow rate ±5 %, temperature +2 °C and -0.032 °C. When the feed flow rate and temperature changed, fluctuation curves of ten parameters including distillate flow rate, bottom flow rate, ethylene concentration in distillate, ethane concentration in bottom, top stage pressure, top stage temperature, reflux ratio, boilup ratio, reboiler level and bottom stage temperature were compared to conform the optimal control strategy. The results show that ratio control scheme 3 is the best according to the system stability and controllability.
