Apparatus and method for purification of gas mixtures

A method for separation of at least one gas component from a mixture of gases, said method comprising the steps of:

• (i) feeding the mixture of gases at a pressure between 5 barg and 150 barg into a feed gas port of a pressure shell containing a plurality of hollow fiber membrane gas separation cartridges, each of which cartridges comprises hollow fiber membranes;
• (ii) passing the mixture of gases into a first of the plurality of hollow fiber membrane gas separation cartridges on a shell side of the hollow fiber membranes, wherein the hollow fiber membranes in the first cartridge remove a portion of at least one first fast gas permeable component from the gas mixture, thereby forming a retentate first effluent stream having a lower concentration of the at least one first fast gas permeable component and a permeate first effluent stream enriched in the at least one first fast gas permeable component as compared to the mixture of gases, and wherein the gas streams on the shell side of the hollow fiber membranes in the first cartridge and the gas streams on a bore side of the hollow fiber membranes in the first cartridge are flowed substantially in a counter-current flow pattern;
• (iii) passing the retentate first effluent stream to a second of the plurality of hollow fiber membrane gas separation cartridges, wherein the hollow fiber membranes in the second cartridge remove a portion of at least one second fast gas permeable component from the retentate first effluent stream, thereby forming a retentate second effluent stream having a lower concentration of the at least one second fast gas permeable component and a permeate second effluent stream enriched in the at least one second fast gas permeable component as compared to the retentate first effluent stream, and wherein the gas streams on a shell side of the hollow fiber membranes in the second cartridge and the gas streams on a bore side of the hollow fiber membranes in the second cartridge are flowed substantially in a counter-current flow pattern;
• (iv) directing the permeate second effluent stream into bores of the hollow fiber membranes of the first cartridge, wherein the permeate second effluent stream acts as sweep gas and is combined with the permeate first effluent stream;
• (v) collecting the retentate second effluent stream from a retentate exit port in the pressure shell;
• and
• (vi) collecting the combined permeate first effluent stream and permeate second effluent stream from a permeate exit port in the pressure shell at a pressure lower than the pressure at which the mixture of gases are fed in step (i).

A gas separation apparatus comprising four or more hollow fiber membrane cartridges arranged into two connected cartridge sequences housed within a pressure shell, each sequence of cartridges comprising two or more cartridges, and the pressure shell having a single feed gas entrance port, a single retentate gas exit port and two permeate gas exit ports;

• wherein each cartridge comprises hollow fibers, a feed gas entrance and a retentate gas exit on a shell side of the hollow fibers, and a permeate gas exit on a bore side of the hollow fibers;
• wherein retentate gas generated by each cartridge in the first sequence of cartridges is used as feed gas for a next cartridge in the first sequence, and the retentate gas from a last cartridge in the first sequence is removed as a retentate product gas from the retentate gas exit port;
• and
• wherein permeate gas generated by each cartridge in the first sequence following a first cartridge in the first sequence is directed into bores of hollow fibers in a preceding cartridge and is used as a sweep gas on a permeate side of the hollow fibers and a combined stream of permeate gasses is removed from a first of the two permeate gas exit ports in the pressure shell;
• and
• wherein retentate gas generated by each cartridge in the second sequence of cartridges is used as feed gas for a next cartridge in the second sequence, and the retentate gas from a last cartridge in the second sequence is removed as a retentate product gas from the retentate gas exit port;
• and
• wherein permeate gas generated by each cartridge in the second sequence following a first cartridge in the second sequence is directed into bores of hollow fibers in a preceding cartridge and is used as a sweep gas on a permeate side of the hollow fibers and a combined stream of permeate gases is removed from a second of the permeate gas exit ports in the pressure shell;
• and
• wherein each permeate gas stream is enriched in at least one fast gas permeable component, and each retentate stream is depleted of said at least one fast gas permeable component.