Use of CFD in modeling MMA solution polymerization in a CSTR

Abstract

A computational fluid dynamics (CFD) model was developed to study methyl methacrylate (MMA) solution polymerization in a lab-scale stationary continuous stirred tank reactor (CSTR) equipped with a six bladed 45° pitched impeller. Azobisisobutyronitrile (AIBN) and ethyl acetate were taken as the initiator and solvent, respectively. The CFD modeling approach incorporated an integration of the continuity, momentum, and species transport equations along with a polymerization source term. The latter was a function of thermal and chemical initiations, transfer to monomer and solvent as well as the gel effect. Multiple reference frame (MRF) technique, laminar regime, and isothermal condition were considered in the modeling. To validate the CFD model, the simulation results of conversion in a stationary CSTR of MMA polymerization were compared with the data reported in the literature. The CFD model was then employed to investigate the impacts of the impeller speed, reaction temperature, residence time and inlet monomer (or solvent) concentration on the conversion and homogeneity of reaction mixture inside the reactor. Contours of monomer mass fraction conceptually facilitated to visualize the reaction progress in the reactor.