Modeling of Particle Size Distributions in Industrial Poly(vinyl chloride) Suspension Polymerization Reactors

In the present paper, a mathematical model is built and implemented to describe the trajectories of mass inventories, pressures and polymer properties with emphasis on final particle size distributions of industrial scale poly(vinyl chloride) suspension polymerization reactors. The model comprises the mass balances, statistical moment balances, equilibrium relationships and population balance equations. A discretization scheme is employed to transform the integro-differential equations resulting from the population balance model into a system of differential equations. The obtained results show, for the first time, that classical breakage and coalescence kernels described in the literature can provide very good fittings of actual industrial scale data when coupled with proper parameter estimation procedures, so that the proposed model is able to represent the available operation data with good accuracy at distinct conditions. Particularly, it is also shown that the use of a top condenser for control of the reactor temperature can lead to changes of parameters that control the particle size distributions.

Automated summary

In this paper, a mathematical model is developed to describe the trajectories and final particle size distributions of poly(vinyl chloride) suspension polymerization reactors on an industrial scale. The model includes mass balances, statistical moment balances, equilibrium relationships, and population balance equations. The results show that classical breakage and coalescence kernels can accurately fit actual industrial data, when combined with proper parameter estimation procedures. It is also found that the use of a top condenser can influence the control of particle size distributions.