Optimization of ethylene oxychlorination fluidized-bed reactor using Differential Evolution (DE) method

Abstract

The present work aims to employ Differential Evolution (DE) algorithm to optimize ethylene oxychlorination process to produce 1,2-dichloroethane in a fluidized bed reactor as a feedstock of PVC production. A steady-state reactor model, based on twophase theory of fluidization, was developed to investigate the effects of various parameters on C2H4 and HCl conversions. The model's results were compared favorably with the industrial data obtained from a pilot plant working in Italy. The feed temperature, pressure, HCl and O2 molar flow rates, and cooling medium temperature were selected as decision variables to minimize the objective function subject to the environmental constraints. The highest performance was found at HCl/C2H4 and O2/C2H4 molar ratios of 2 and 0.55, respectively; feed and cooling medium temperatures of 440 and 360 K, respectively; pressure of 367.6 kPa. The results show a decrease of 20°C in the feed temperature, which leads to saving energy and reducing the size of the pre-heater.