“Experimental and modeling study of ethylene polymerization in gas phase reactors: impact of thermodynamics”
Participants au projet pour le LAGEP: Nida Sheibat-Othman (Coordinatrice)
Partners: LCPP/ Villeurbanne, ETH Zürich / Switzerland
Résumé: The aim of this project is to develop a fundamental understanding of the different phenomena observed during condensed mode cooling in ethylene polymerization, and translate this new knowledge into a sophisticated model able to predict the reactor performance. Accordingly, the project is organized into three subsequent tasks covering the different scales typical of the system, from the single particle to the reactor. Namely, the equilibrium partitioning of different species (monomer, comonomers, solvents, inerts) into polyethylene films and particles will be studied experimentally using different techniques. Then, such thermodynamic knowledge will be incorporated into a single-particle model accounting for the reaction and diffusion phenomena as well as the thermal behavior. Such model will be validated by comparison with experimental data obtained using specially designed spherical stirred bed reactors that are well adapted for gas phase polymerization. Finally, taking advantage of computational efficient methods, a comprehensive model of stirred-bed reactor will be developed, accounting for all phenomena affecting the particle size distribution, such as aggregation due to polymer softening related to the plasticization induced by additional species.