Dual reflux PSA

A dual reflux PSA cycle with both stripping and enriching has been proposed to obtain high enrichment and recovery. The separation is much better than that obtainable by normal PSA and suggests that it is possible to obtain two nearly pure products from a dilute feed stream [see Mclntire et al., Ind. Eng. Chem, Res., 41, 3499 (2002)]. 

Diagne, D., Goto, M. and Hirose, T., Numerical Analysis of a Dual Refluxed PSA Process during Simultaneous Removal and Concentration of Carbon Dioxide Dilute Gas from Air, J. Chem. Tech. Biotechnol., 65 (1996) pp. 29-38. 

Ebner A. E. and Ritter J. A., Dual Reflux PSA for the Complete Separation of Binary Gas Streams, AlChE J., submitted (2002). 

The consequence of these works is the redefinition of PSA cycles as stripping and rectifying, by drawing a direct analogy with distillation. Hirose and coworkers [2] and McIntyre, et al. [4] showed further that it is possible to combine both configurations into a dual reflux (DR) PSA... 

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