(377b) Incorporating a Vacuum Pump Performance Curve in Cyclic Adsorption Process Simulation

Authors: 
Jiang, H., University of South Carolina
Ritter, J. A., University of South Carolina
Ebner, A. D., University of South Carolina
Pressure varying steps, and depressurization steps in particular that utilize vacuum, are key to achieve optimum performance of pressure swing adsorption (PSA) processes. Recovery, enrichment, throughput and separation energy are intimately dependent on how and to what extent depressurization in the cycle is achieved. To gain a clearer understanding of its role in PSA processes, it is necessary that models provide adequate representation of the dynamics involved during vacuum depressurization.

One key area of interest is to properly represent how pressure and flow interact at the exit of a PSA bed. To date, most models utilize a valve equation to artificially represent the dynamics of a vacuum pump. This may lead to completely erroneous performance results because the dynamic response of the valve equation may not at all represent the dynamics of any existing vacuum pump that may be used in a PSA process. To this end, an actual pump pressure-flow relationship has been incorporated into the dynamic adsorption process simulator (DAPS) at the exit of the bed with and without mediation of a valve equation to capture the role of a vacuum pump on the performance of a vacuum depressurization step. The latest result from this work will be presented.