A review on modeling and control of olefin polymerization in fluidized-bed reactors

Abstract

<jats:title>Abstract</jats:title> <jats:p>This is a detailed review on olefin polymerization models, and the most recent process control approaches used to control these nonlinear systems are presented. Great focus has been given to the various approaches of fluidized-bed reactor (FBR) modeling. Currently, there has yet to be a single model that blends these modeling aspects together into one single formulation. In this article, the classification of models works by looking at their assumption in considering the phases inside the system. Researchers have been unraveling vast information to narrate in detail the relations between various variables that can be found in FBRs. Although it is not difficult to understand about the basics of modeling polymer properties, a gap exists for future researchers to justify in detail the phenomena and reduce the gap between model predictions and the actual data. The various controlling approaches to control these FBRs have also been reviewed and categorized depending on the method they used to control significant parameters of this nonlinear system. The progress that can be expected in this field leads to the creation of more efficient reactors and minimizing waste.</jats:p>

Computational fluid dynamics simulation of gas–liquid–solid polyethylene fluidized bed reactors incorporating with a dynamic polymerization kinetic model

“…The mechanisms of polymerization kinetics on a Ziegler-Natta catalyst involve a series of elementary reactions and are extremely complicated, which therefore are always described as a simple kinetics model in most works. [5][6][7][8][9][17][18][19]27,28,[33][34][35] As a result, the polymerization FBRs lose much microscale information about polyethylene products properties such as reactant composition changes, molecular weight, and production rate. In this work, a comprehensive polymerization kinetics proposed by McAuley et al 29 is used.…”

Advances in Mathematical Modeling of Gas-Phase Olefin Polymerization

“…The implementation of mathematical models, namely macroscale modeling, mesoscale modeling, microscale modeling, single particle modeling, computational fluids dynamic modeling, microelements modeling, 2D finite element modeling, single pore modeling, and parti-level fragmentation modeling to determine the properties of the polyolefin, and the mass and heat transfer phenomena during the polymerization process. [8,11,12,22,[31][32][33][34] 7. Quality Control Different types of analysis such as nuclear magnetic resonance (NMR), temperature rising elution fractionation (TREF), gel permeation chromatography (GPC), rheological characterization (zero shear viscosity, zero shear viscosity, shear thinning behavior, dynamic modulus, loss angle, Van-Gurp-Palmen plot, Cole-Cole plot, activation energy, thermorheological complexity, strain-hardening effect, relaxation time, damping function, nonlinear dynamical oscillatory shear, and long-chain branching index), dynamic mechanical analysis, differential scanning calorimeter, neutron scattering, and molecular topology fractionation.…”

“…[ [37][38][39] From the past reviews summarized in Table 1, none of the above review studies reviewed and discussed kinetic modeling together with mass and energy balance modeling in the gas phase. The review article published by Abbasi et al (2018) [34] only focused on a fluidized bed reactor and did not cover other types of reactors such as tubular reactor or stirred bed reactor. In addition, none of the above review studies proposed simple or proper guidelines to implement and simulate the mathematical model for this olefin polymerization process.…”

Gas phase polymerization of ethylene towards UHMWPE

“…Moreover, to increase the mass transfer from gas to liquid, the pressure should be increased. In Fluidized Beds however, since there is no limitation in mass transfer [4], the reactor can be operated in lower pressures [5], and having no solvents, offers an easier and cheaper operation. While to use FBR technology seems more advantageous over slurry reactor technology, one can wonder why FBR technology does not take its place in UHMWPE process.…”