Heat and Mass Transfer Australasia

ISBN Print: 978-1-56700-099-3

ADSORBER-REGENERATORS; NUMERICAL MODELS OF THE INFLUENCE OF LOCALISED HEAT LOSS

DOI: 10.1615/978-1-56700-099-3.480
pages 399-406

Abstract

In this paper the coupled equations for species and temperature transport through a packed bed region of an adsorber-gegenerator are presented. The storage of species in the solid phase, with subsequent implications for mass transfer, is allowed for. Temperature is treated assuming a large Biot number. The equations are discretised and solved with a second order PetrofF-Galerkin scheme.

The novel aspect of the work is that the solution for coupled heat transfer and mass transfer is presented for two dimensions, permitting the influence of localised cooling to be established throughout the bed.

Predictions for a shallow bed adsorber, removing CO2, show the effects of applying cooling at the side walls. Whilst temperatures along the side increase by a maximum of 10°C, those along the centre line of the bed increase by as much as 100°C. In consequence the time for 'breakthrough' of CO2 into the exit stream is 5200s if the behaviour of adsorbent near the wall is considered, but reduced to 4500s for that along the centre line.