Patent ID: 7104531

Claim:
A refillable apparatus for dissolving a gas in a liquid and for dispensing the gas-containing liquid, the apparatus comprising a pressurizable vessel having a single external duct for passage of liquid into and out of the vessel and a single external duct for passage of a gas into and out of the vessel, the vessel containing: (1) a liquid whose level is allowed to vary between two predetermined levels within the vessel; (2) a contactor module held vertically and always at least partially immersed in the liquid, comprising hydrophobic gas permeable hollow fibers having bore volumes within a shell, the fibers extending from their lower end where they are closed, and passing through an uppermost seal in the shell which is constructed to separate the volume of the shell below the seal, where only the outer surfaces of the fibers are in contact with the liquid over their length below the seal, from the upper volume of the shell where the gas entering the gas duct of the vessel communicates at all times with the bore volumes of the fibers and the surface of the liquid contacting the exterior of the module, the module having: (a) a channel at its immersed lower end, where the fiber ends are sealed, allowing communication of the liquid within the module with the liquid in the vessel contacting the module; and (b) a channel at its upper end positioned below the fiber seal to allow communication of the liquid within the module with the single external duct for the liquid; and (3) any remaining space in the vessel being occupied by the gas under pressure.