Simulation And Analysis Of Ethylene Polymerization Using GPROMS Platform

In this work, a simulation platform combining gPROMS and Aspen Plus based on CAPE-OPEN standard, was developed for ethylene polymerization process. The model of slurry reactor, which is widely used for broad molecular weight distribution (MWD) ethylene polymerization in industry, was built by gPROMS. Based on the model, a simulation platform was established to emulate the polymerization process using Ziegler-Natta catalyst with five active sites and reparameterized PC-SAFT property method from Aspen Plus.The influence of main operation parameters, i.e., connection mode of reactors, hydrogen flowrate and catalyst flowrate, on the polymerization process was investigated and an optimum condition for bimodal polyethylene production was determined. The concept design for slurry polymerization with reactors in series was conducted by steady-state and dynamic simulation. Under the steady-state condition, the hydrogen flowrate plays the major role in the number average molecular weight (Mn) of the first reactor and the weight average molecular weight (Mw) of the second reactor. Besides, under the dynamic condition, the effect of production load was evaluated, demonstrating the good operating flexibility of the process.The results obtained from this simulation platform agreed well with those from other literatures, proving the suitability of the platform for this process.