The separation of air into nitrogen and oxygen is widely practiced. Cryogenic distillation is most economical for processing 100 to 5,000 tons of air per day, while pressure-swing-adsorption is favorable for 20 to 50 tonslday. For small-volume users requiring less than 10 tonslday, gas permeation finds applications where for a single stage, either an oxygen-enriched air (40 mol% oxygen) or 98 mol% nitrogen can be produced. It is desired to produce 5 tonslday (2,000 lb/ton) of 40 mol% oxygen and nitrogen, ideally of 90 mol% purity, by gas permeation. Assume pressures of 500 psia (feed side) and 20 psia (permeate). Two companies, who can supply the membrane modules, have provided the following data:

Determine the required membrane area in m2 for each company.

Assume that both module types approximatecrossflow.

Transcribed Image Text:

Company A Company B Spiral-wound 35 1.9 Module type PM for O2, barrer/µm PMoz Hollow-fiber 15 3.5 ,/PMN2