Numerical simulation and experimental validation of multiple-layer, non-isothermal, bulk gas pressure swing adsorption

This paper investigates the ability of a detailed numerical model of multiple-layer, non-isothermal, bulk gas pressure swing adsorption processes to match experimental data over a range of operating conditions. The experimental apparatus is a 2-bed, 8-step VSA process for air separation using multiple layers of alumina and CaX zeolite. Input parameters are determined independently of the VSA system and no parameters in the model are adjusted to improve the fit to experimental data. A limited range of system purities and pressure swings are examined to illustrate the ability of the numerical model to capture overall performance. In general good agreement is obtained between the model and the experimental data although accurate modelling requires careful attention to details that influence the thermal behaviour of the process. The numerical model can also represent the unusual temperature profiles characteristic of multiple-layered beds. Overall, while good agreement can be obtained between model and experimentation, accurate design must still rely on experimental work. The model is, however, sufficiently accurate to permit approximate optimisation studies to be performed.