(449av) CO2 Removal from CO2-CH4 Mixtures Using a Shell-and-Tube Separator and Its CFD Analysis | AIChE

(449av) CO2 Removal from CO2-CH4 Mixtures Using a Shell-and-Tube Separator and Its CFD Analysis

Authors 

Kato, T. - Presenter, Utsunomiya University
Itoh, N., Utsunomiya University
Sato, T., Utsunomiya University
Kanno, Y., Utsunomiya University
 For more precise analysis for various types of membrane separators, modelling using computational fluid dynamics (CFD) is very useful because of taking into account all the distributions with respect to flow rate, concentration, pressure and temperature. Even for a shell-and-tube separator, being the simplest configuration among the flow types, to more accurately determine the concentration dependence of zeolite membrane permeance during separation of CH4-CO2 mixture those phenomena should be considered.

 The performance of the gas separator for binary CH4-CO2 mixture with zeolite membrane is experimentally known to be influenced by the composition, which can change along the length of separator: this makes it more difficult to formulate the concentration dependency. Then, it was assumed that the permeances of CO2 and CH4 were as follows; PCO2=PCO20(1+a(1-x)) and PCH4=PCH40(1+bx), where x was the mol fraction of CO2. The CFD code used in this study is STAR-CCM+. The constant a and b is determined so as to agree with the experimental result. It was made clear that the permeances of two gases for the chabazite zeolite membrane show the concentration dependences assumed. In addition, the concentration distribution and flow rate within the separator were visualized, helping understand the separation manner inside the separator employed.