Patent ID: 7279029

Claim:
A system for producing an oxygen-rich gas comprising (a) a primary gas mover including a first compressor adapted to compress atmospheric air to provide pressurized feed air and a second compressor adapted to compress a waste gas from subatmospheric pressure to atmospheric pressure, wherein the primary gas mover is characterized by a weight W p ; (b) a drive motor adapted to drive the first and second compressors; (c) a rechargeable power supply adapted to supply power to the drive motor, wherein the rechargeable power supply is characterized by a weight W b ; and (d) a pressure/vacuum swing adsorption unit adapted to separate the pressurized feed air into an oxygen-rich product at a product flow rate F p and an oxygen-depleted waste gas, wherein the adsorption unit comprises a plurality of adsorber beds containing an adsorbent, wherein the total amount of the adsorbent contained in the adsorber beds is characterized by a total adsorbent weight W a ; wherein the combined weight, W t , of the adsorbent, the primary gas mover, and the rechargeable power supply is characterized by the expression 0.75 F p <W t <2.02 F p where F p is in liters per min (at 23° C. and 1 atma pressure) and W a , W p , and W b are in pounds.