Abstract
Beginning with Lynn and Huff [A.I.Ch.E.J. 17, 475 (1971)], variable viscosity models have been applied to polymerization in tubular reactors. Such models can become quite complex and are difficult to verify based just on the usual experimental responses of conversion, number and weight average molecular weights, and effluent temperature. Verification of predicted velocity profiles is particularly important for scale-up processes. The present study reports the validation of the velocity profile predictions using residence time measurements. The process model for the styrene polymerization is based on the steady state, two-dimensional equations of mass energy and momentum transport. It contains adjustable parameters. This model predicts axial and radial velocity profiles which are then used in a tracer model. The tracer model consists of the unsteady, two-dimensional convective diffusion equation. It was solved using an apparently new technique which decouples the steps of axial convection and radial diffusion. The validity of this technique was confirmed by comparison with analytical solutions. Experimental measurements were made on tubular reactors having inside diameters of 0.011 and 0.033 m. Styrene conversions were approximately 20%. Mean residence times were 3600 s. The residence time distribution was measured using toluene as the inert tracer. Results showed excellent agreement with model predictions.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.