A model for the devolatilization of EPDM rubber in a series of steam stripping vessels



A mathematical model was developed for the multitank stripping section of industrial ethylene propylene diene monomer (EPDM) rubber processes. Experiments were conducted to determine Henry's law coefficients and diffusivities for hexane solvent and 5-ethylidene-2-norbornene (ENB) comonomer in EPDM particles. Equivalent radii for diffusion within the particles were also determined. A model was developed to predict solvent and comonomer concentrations in a single particle as it moves through a series of tanks with different operating conditions. A second, more-complicated model was then developed to account for a continuous flow stirred tank residence time distribution for the particles in the tanks. Data from three industrial plants were used to estimate parameters and assess the models' predictive ability. Typical prediction errors are 0.90 wt % for residual hexane and 0.14 wt % for residual ENB. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2596–2606, 2014