Can steady-state momentum equations be used in modelling pressurization of adsorption beds?

• Type: Article in International Scientific Journal
• Date: 1993

Authors

Sereno, C (Author) Other; Alírio Rodrigues (Author) FEUP

Journal

Title: Gas Separation and Purification

Vol. 7

Pages: 167-174

ISSN: 0950-4214

Publisher: Pergamon Press - Elsevier

Indexing

Scopus - 30 Citations

Other information

Authenticus ID: P-007-610

Abstract (EN): Modelling of pressurization and blowdown steps of a pressure swing adsorption (PSA) cycle has been carried out using a steady-state momentum equation (Darcy or Ergun) locally in the bed. There has been some controversy about the validity of such an approach since Darcy's or Ergun's equations are strictly valid only for quasi-stable flow, and during pressurization at short times, the flow is unstable. In order to check the assumptions usually made in modelling isothermal pressurization, three models are developed. Model I includes mass balance and unsteady-state mechanical energy balance for a packed bed with non-porous, inert particles; Model II neglects the kinetic energy change in the mechanical energy balance and Model III considers a steady-state mechanical energy balance. The latter model is the one used in previous work. The numerical tool used to solve all the model equations is the moving finite element method (MFEM) with polynomial approximation of any degree in each element developed by C. Sereno1. Comparison of simulation results for the various models showed that steady-state momentum equations can be safely used in modelling pressurization of adsorbers. © 1993.

Language: English

Type (Professor's evaluation): Scientific