DYNAMICS OF PACKED BEDS WITH INTRAPHASE HEAT OR MASS TRANSFER

An extension of the finite stage model is proposed to describe the dynamic behaviour of packed bed heat exchangers and adsorbers. The model allows for axial dispersion, interphase resistance and intraparticle diffusion in the absence of gross radial transfer. A comparison between the proposed finite stage model and the axial dispersion model is made using the techniques of frequency response and moments analysis. Close correspondence is revealed between the two and it is concluded that (in the absence of decisive experimental data) either may be used. The finite stage model proposed has the advantage, however, that intraparticle diffusion effects may be much more simply allowed for. © 1968.