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A method of and an arrangement for increasing the enrichment of nitrogen in an effluent gas obtained from a pressure swing adsorption system includes electrostatically negatively charging oxygen molecules in a feed gas such as air, and attracting the negatively charged oxygen molecules to a positive

A method of and an arrangement for increasing the enrichment of nitrogen in an effluent gas obtained from a pressure swing adsorption system includes electrostatically negatively charging oxygen molecules in a feed gas such as air, and attracting the negatively charged oxygen molecules to a positively charged molecular sieve coke material employed as adsorbers in the pressure swing adsorption process.

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1. In an adsorption process of the type wherein a feed gas comprised of two components is loaded in an adsorber operative for selectively adsorbing one of the components, and an effluent gas enriched in the other of the components is conveyed from the adsorber, a method of increasing the enrichme

1. In an adsorption process of the type wherein a feed gas comprised of two components is loaded in an adsorber operative for selectively adsorbing one of the components, and an effluent gas enriched in the other of the components is conveyed from the adsorber, a method of increasing the enrichment of said other component contained in the effluent gas, comprising the steps of: (a) differentially electrostatically charging the two components of the feed gas to electrostatically charge said one component greater than said other component with a charge having a first polarity; and (b) electrostatically charging the adsorber during loading thereof with a charge having a second opposite polarity, thereby electrostatically to attract said greater charged one component to said oppositely charged adsorber during the loading thereof. 2. In the adsorption process as defined in claim 1, wherein an unloaded gas enriched in said one selectively adsorbed component is unloaded from the adsorber, the method further comprising the step of oppositely electrostatically charging the adsorber during unloading thereof with a charge having said first polarity while said one component remains charged with a charge of said same first polarity, thereby electrostatically to repel said charged one component from said same charged adsorber during the unloading thereof. 3. The method as defined in claim 1, wherein said differentially charging step includes the steps of positioning a dielectric-coated field terminal in an electrically-conductive vessel in which the adsorber is contained and electrically connecting an output of an electrical high constant voltage source to the field terminal, and wherein said adsorber charging step includes electrically connecting another output of the electrical high constant voltage source to the vessel. 4. The method as defined in claim 3, wherein said positioning step includes locating the field terminal within the adsorber and for a predetermined distance lengthwise of the same. 5. The method as defined in claim 4, wherein said positioning step includes locating a plurality of additional field terminals, all electrically connected to one another, at spaced-apart locations within the adsorber. 6. In the adsorption process as defined in claim 1 of the pressure swing adsorption type, wherein the feed gas is air; and wherein the adsorber constitutes a multitude of molecular sieve coke pellets contained in a vessel, and operative for selectively adsorbing oxygen as said one component, and for enriching the effluent gas with nitrogen as said other component, the method wherein the effluent gas is enriched with nitrogen to an amount greater than that obtained by the adsorber alone. 7. In an adsorption system of the type wherein a feed gas comprised of two components is loaded in an adsorber operative for selectively adsorbing one of the components, and an effluent gas enriched in the other of the components is conveyed from the adsorber, an arrangement for increasing the enrichment of said other component contained in the effluent gas, comprising: (a) means for differentially electrostatically charging the two components of the feed gas to electrostatically charge said one component greater than said other component with a charge having a first polarity; and (b) means for electrostatically charging the adsorber during loading thereof with a charge having a second opposite polarity, thereby electrostatically to attract said greater charged one component to said oppositely charged adsorber during the loading thereof. 8. In the adsorption system as defined in claim 7, wherein an unloaded gas enriched in said one selectively adsorbed component is unloaded from the adsorber, the arrangement further comprising means for oppositely electrostatically charging the adsorber during unloading thereof with a charge having said first polarity while said one component remains charged with a charge of said same first polarity, thereby electrostatically to repel said charged one component from said same charged adsorber during the unloading thereof. 9. In the adsorption system of claim 7 of the pressure swing adsorption type wherein the feed gas is air; and wherein the adsorber constitutes a multitude of molecular sieve coke pellets contained in an electrically-conductive vessel, and operative for selectively adsorbing oxygen as said one component and for enriching the effluent gas with nitrogen as said other component, the arrangement wherein said differentially charging means includes an electrical voltage supply having a high constant voltage across a pair of outputs; a dielectric-coated field terminal means positioned in and surrounded, at least in part, by the pellets; and means for electrically connecting one output of the voltage supply to the field terminal means; and wherein said electrostatically charging means includes means for electrically connecting the other output of the voltage supply to the vessel. 10. The arrangement as defined in claim 9, wherein the differentially charging means negatively charges the oxygen, and the electrostatically charging means positively charges the vessel and, in turn, the pellets contained therein during the loading. 11. The arrangement as defined in claim 9, wherein the field terminal means comprises at least one elongated dielectric-coated metallic rod extending lengthwise along and in the vessel, said rod being surrounded, at least partially, by the pellets within the vessel. 12. The arrangement as defined in claim 9, wherein the field terminal means comprises a dielectric-coated mesh which is located adjacent an air inlet of the vessel and which has apertures through which the air passes, and a plurality of elongated dielectric-coated metallic rods electrically connected to the mesh and extending therefrom toward an outlet of the vessel; said mesh and rods being surrounded, at least in part, by the pellets in the vessel. 13. In a pressure swing adsorption system of the type wherein, during a loading phase, air is conveyed through an inlet of an electrically-conductive vessel in which is contained a multitude of molecular sieve coke pellets operative for selectively adsorbing oxygen from the air, and an effluent gas enriched in nitrogen from the air is conveyed through an outlet of the vessel and, during a subsequent unloading phase, an unloaded gas enriched with the selectively adsorbed oxygen is unloaded through the outlet of the vessel, an arrangement for increasing the enrichment of the nitrogen contained in the effluent gas, comprising; (a) an electrical voltage supply having a negative output and a positive output across which a high constant voltage is present; (b) a dielectric-coated field mesh overlying the inlet of the vessel and on which at least a portion of the pellets are supported, said mesh having apertures through which the air is conveyed; (c) a plurality of dielectric-coated field rods connected to the mesh and extending therefrom through the multitude of the pellets surrounding the rods toward the outlet of the vessel; (d) means for electrically connecting the negative output of the voltage supply to the rods and the mesh for electrostatically negatively charging the oxygen in the circumambient region of the rods and mesh to a greater extent than the nitrogen; (e) means for electrically connecting the positive output of the voltage supply to the vessel during the loading phase for electrostatically positively charging the vessel and the pellets contained within the same, thereby electrostatically to attract the negatively charged oxygen to the positively charged pellets during the loading phase to increase the enrichment of the nitrogen in the effluent gas; and (f) means for electrically connecting the negative output of the voltage supply to the vessel during the unloading phase for electrostatically negatively charging the pellets while the oxygen remains negatively charged, thereby electrostatically to repel the negatively charged oxygen from the negatively charged pellets during the unloading phase. 14. In the system as defined in claim 13, wherein the effluent gas has a purity of about 99.9% nitrogen due to the action of the molecular sieve coke pellets, and wherein the arrangement is operative for increasing the purity of the effluent gas to over 99.9% nitrogen.