Experimental investigations have been carried out on oxygen enrichment of air by permeation through silicone-capillary membranes in a permeator, with partial or total recycle of the oxygen-enriched permeate to the fresh-air feed. A vacuum recycle mode was utilized, and permeate pressures were in the range from 1.013 X 103to 4.053 X 103Pa (0.01-0.04 atm) for feed air pressure varying between 1.023 X 105and 1.114 X 105Pa (1.01-1.10 atm). Permeator performances are determined for the recycle ratios of 0.0, 0.1990, 0.6067, 0.7462, 0.9039, and 1.0. A model incorporating axial pressure drop and capillary deformation is proposed for the recycle permeator. Model simulations agree with the experimental data quite well for all recycle ratios. For high recycle ratios, the recycle permeator displays a maximum in oxygen enrichment at a finite net stage cut. This maximum increases as the recycle ratio is increased. A recycle permeator is a convenient way to produce a richer permeate than can be obtained from a permeator operating in the conventional mode. However, the compressor power and membrane area required per unit net permeated product increases with recycle.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)
- Industrial and Manufacturing Engineering