Jr-Wei Tu1 and Chii-Dong Ho This email address is being protected from spambots. You need JavaScript enabled to view it.1

1Department of Chemical and Materials Engineering, Tamkang University, Tamsui, Taiwan 251, R.O.C.


 

Received: March 10, 2006
Accepted: May 25, 2006
Publication Date: December 1, 2006

Download Citation: ||https://doi.org/10.6180/jase.2006.9.4.05  


ABSTRACT


A new design of multi-pass mass exchanger with external recycle and the mass transfer in such a device have been investigated theoretically in this study. The analytical solutions were obtained by applying an orthogonal expansion technique associated with the eigenfunction expanding in terms of an extended power series. The influences of the design parameters (the subchannel height ratio, , and permeable membrane parameter, ) and operating conditions (the recycle ratio, R, and mass-transfer Graetz number, Gzm) on the outlet concentration and mass transfer rate were discussed and represented graphically. Comparing to the single-pass mass exchangers without external recycle, the mass transfer efficiency was improved by employing the multi-pass devices with external recycle. In economic sense, the optimal operating conditions, say R = 1, βab = βcd = 1/3 and Gzm > 30 for ϒ= 10, were selected by considering both the mass transfer efficiency improvement and power consumption increment in this study.


Keywords: Mass Transfer, External Recycle, Multi-Pass Operations, Conjugated Graetz Problem


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