Steady And Dynamic Simulation Of Proplyene Polymeriation

Hypol technology is widely used in industrial propylene polymerization. This paper establishes a steady and dynamic model of Continuous Stirred Tank Reactor (CSTR) for propylene polymerization. Rate constant parameters for polymerization reactions are calculated through date-fitting using operating data from real industrial reactors. The model can count the important index of production, such as slurry concentration in the reactor, output of products, MWN and Melt index of polypropylene. Effects of materials input flow rate and ratio of hydrogen-propylene variation on the reaction are studied. Furthermore, a simulation of product grade change is carried out. Using the dynamic model, we studied the optimal control of the polypropylene product grade transition process.1. In this thesis a rigorous thermodynamics model of PC-SAFT equation of state and the Ziegler-Natta polymerization kinetic model available in Polymers Plus is selected for simulation model. The phase equilibrium model will be extended in the future to include vapor-liquid-liquid phase equilibrium. The Ziegler-Natta polymerization kinetic model supplies to the reactor models the reaction rates for the components and the rate of change of polymer properties. The actual number of site types necessary to model a given catalyst-polymerization system is determined by deconvolution of the polymer molecular weight distribution curve obtained from a GPC analysis.2. The steady state model has been applied to study industrial propylene polymerization in steady state. The results include component mass flowrates, thermophysical information (temperature, pressure, enthalpy, etc.) and catalyst and polymer attributes. The simulation results indicate effects on the characteristics of propylene polymerization process.3. The study of different processes and operations in dynamic behavior of propylene polymerization has been done in detail using the dynamic simulation...