# US 2013/0239804 A1 · Membrane-Based Gas Separation Process Using Ejector-Driven Gas Recycle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0239804 A1 - Document ID: US20130239804A1 - Status: Published application - Kind: A1 - Application number: 13/422,344 - Filed: 2012-03-16 - Published: 2013-09-19 - Earliest claimed: 2012-03-16 - Assignees: Membrane Technology and Research, Inc. - Inventors: Nicholas P. Wynn; Haiqing Lin; Meijuan Zhou; Jennifer H. Ly; Adrian Serbanescu-Martin - Web page: https://patentgrep.com/patent/US20130239804A1 ## CPC - B01D 53/229: {Integrated processes (Diffusion and at least one other process, e.g. adsorption, absorption)} - B01D 53/226: {in serial connexion} - B01D 53/047: Pressure swing adsorption - B01D 53/14: by absorption - B01D 2256/245: Methane - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) ## Abstract Disclosed herein is a gas separation process that utilizes ejector recycle with a membrane separation step in combination with a second separation step. The second separation step may be a second membrane separation step, or may involve a different type of separation process. ## Claims ### Claim 1 A process for separating a gas mixture into two or more gas components, comprising: (a) providing an ejector including a motive gas inlet, a suction gas inlet, and a mixed gas outlet; (b) passing to the motive gas inlet a motive gas comprising a gas mixture that includes at least a first gas component and a second gas component that is different from the first gas component; (c) passing a suction gas to the suction gas inlet; (d) withdrawing from the mixed gas outlet a mixed gas comprising the motive gas and the suction gas; (e) providing a membrane having a feed side and a permeate side, wherein the membrane is selective to the first gas component relative to the second gas component; (f) passing the mixed gas across the feed side; (g) withdrawing from the permeate side a permeate stream that is enriched in the first gas component relative to the mixed gas; (h) withdrawing from the feed side a residue stream that is depleted in the first gas component relative to the mixed gas; (i) passing the residue stream to a second separation unit to perform a second separation step; (j) withdrawing from the second separation unit a non-product stream that is depleted in the second gas component relative to the residue stream; and (k) passing at least a portion of the non-product stream back to the ejector as the suction gas. ### Claim 2 (depends on 1) A process in accordance with claim 1, wherein the second separation step is a flow-through step that leaves the non-product stream at essentially the same pressure as the mixed gas. ### Claim 3 (depends on 1) A process in accordance with claim 1, wherein the second separation step is a partial pressure-driven process. ### Claim 4 A process for separating a gas mixture into two or more gas components, comprising: (a) providing an ejector including a motive gas inlet, a suction gas inlet, and a mixed gas outlet; (b) passing to the motive gas inlet a motive gas comprising a gas mixture that includes at least a first gas component and a second gas component that is different from the first gas component; (c) passing a suction gas to the suction gas inlet; (d) withdrawing from the mixed gas outlet a mixed gas comprising the motive gas and the suction gas; (e) providing a membrane having a feed side and a permeate side, wherein the membrane is selective to the first gas component relative to the second gas component; (f) passing the mixed gas across the feed side; (g) withdrawing from the permeate side a permeate stream that is enriched in the first gas component relative to the mixed gas; (h) withdrawing from the feed side a residue stream that is depleted in the first gas component relative to the mixed gas; (i) passing the residue stream to a partial condenser; (j) withdrawing from the partial condenser an overhead gas stream that is depleted in the second gas component relative to the residue stream; and (k) passing at least a portion of the overhead gas stream back to the ejector as the suction gas. ### Claim 5 A process for separating a gas mixture into two or more gas components, comprising: (a) providing an ejector including a motive gas inlet, a suction gas inlet, and a mixed gas outlet; (b) passing to the motive gas inlet a motive gas comprising a gas mixture that includes at least a first gas component and a second gas component that is different from the first gas component; (c) passing a suction gas to the suction gas inlet; (d) withdrawing from the mixed gas outlet a mixed gas comprising the motive gas and the suction gas; (e) providing a membrane having a feed side and a permeate side, wherein the membrane is selective to the first gas component relative to the second gas component; (f) passing the mixed gas across the feed side; (g) withdrawing from the permeate side a permeate stream that is enriched in the first gas component relative to the mixed gas; (h) withdrawing from the feed side a residue stream that is depleted in the first gas component relative to the mixed gas; (i) passing the residue stream to an absorption unit; (j) withdrawing from the absorption unit an overhead gas stream that is depleted in the second gas component relative to the residue stream; and (k) passing at least a portion of the overhead gas stream back to the ejector as the suction gas. ### Claim 6 A process for separating a gas mixture into two or more gas components, comprising: (a) providing an ejector including a motive gas inlet, a suction gas inlet, and a mixed gas outlet; (b) passing to the motive gas inlet a motive gas comprising a gas mixture that includes at least a first gas component and a second gas component that is different from the first gas component; (c) passing a suction gas to the suction gas inlet; (d) withdrawing from the mixed gas outlet a mixed gas comprising the motive gas and the suction gas; (e) providing a first membrane having a first feed side and a first permeate side, wherein the first membrane is selective to the first gas component relative to the second gas component; (f) passing the mixed gas across the first feed side; (g) withdrawing from the first permeate side a first permeate stream that is enriched in the first gas component relative to the mixed gas; (h) withdrawing from the first feed side a first residue stream that is depleted in the first gas component relative to the mixed gas; (i) providing a second membrane having a second feed side and a second permeate side, wherein the second membrane is selective to the second gas component relative to the first gas component; (j) passing the first residue stream across the second feed side; (k) withdrawing from the second permeate side a second permeate stream that is enriched in the second gas component relative to the first residue stream; (l) withdrawing from the second feed side a second residue stream that is depleted in the second gas component relative to the first residue stream; and (m) passing at least a portion of the second residue stream back to the ejector as the suction gas. ### Claim 7 A process for separating a gas mixture into two or more gas components, comprising: (a) providing an ejector including a motive gas inlet, a suction gas inlet, and a mixed gas outlet; (b) passing to the motive gas inlet a motive gas comprising a gas mixture that includes at least a first gas component and a second gas component that is different from the first gas component; (c) passing a suction gas to the suction gas inlet; (d) withdrawing from the mixed gas outlet a mixed gas comprising the motive gas and the suction gas; (e) providing a membrane having a feed side and a permeate side, wherein the membrane is selective to the first gas component relative to the second gas component; (f) passing the mixed gas across the feed side; (g) withdrawing from the permeate side a permeate stream that is enriched in the first gas component relative to the mixed gas; (h) withdrawing from the feed side a residue stream that is depleted in the first gas component relative to the mixed gas; (i) passing the residue stream to a pressure swing adsorption unit; (j) withdrawing from the pressure swing adsorption unit a residue gas stream that is depleted in the second gas component relative to the residue stream; and (k) passing at least a portion of the residue gas stream back to the ejector as the suction gas. ### Claim 8 A process for separating a gas mixture into two or more gas components, comprising: (a) providing an ejector including a motive gas inlet, a suction gas inlet, and a mixed gas outlet; (b) passing to the motive gas inlet a motive gas comprising a gas mixture that includes at least a first gas component and a second gas component that is different from the first gas component; (c) passing a suction gas to the suction gas inlet; (d) withdrawing from the mixed gas outlet a mixed gas comprising the motive gas and the suction gas; (e) passing the mixed gas to a first separation step; (f) withdrawing from the first separation step a product stream that is enriched in the first gas component relative to the mixed gas; (g) withdrawing from the first separation step a non-product stream that is depleted in the first gas component relative to the mixed gas; (h) providing a membrane having a feed side and a permeate side, wherein the membrane is selective to the second gas component relative to the first gas component; (i) passing the non-product stream across the feed side; (j) withdrawing from the permeate side a permeate stream that is enriched in the second gas component relative to the non-product stream; (k) withdrawing from the feed side a residue stream that is depleted in the second gas component relative to the non-product stream; and (l) passing at least a portion of the residue stream back to the ejector as the suction gas. ### Claim 9 (depends on 8) A process in accordance with claim 8, wherein the first separation unit is a partial condenser. ### Claim 10 (depends on 8) A process in accordance with claim 8, wherein the first separation unit is an absorption unit. ### Claim 11 (depends on 8) A process in accordance with claim 8, wherein the first separation unit is a pressure swing adsorption unit. ### Claim 12 An apparatus for separating a gas mixture into two or more gas components, comprising: (a) an ejector including a motive gas inlet, a suction gas inlet, and a mixed gas outlet; (b) a first separation unit in gas communication with the mixed gas outlet, wherein the first separation unit has a first product outlet and a first non-product outlet; and (c) a second separation unit in gas communication with the first non-product outlet, wherein the second separation unit has a second product outlet and a second non-product outlet, and wherein the second non-product outlet is in gas communication with the suction gas inlet. ### Claim 13 (depends on 12) An apparatus in accordance with claim 12, wherein the first separation unit is a membrane separation unit. ### Claim 14 (depends on 13) An apparatus in accordance with claim 13, wherein the second separation unit is selected from the group consisting of: a partial condenser, an absorption unit, a pressure swing adsorption unit, and a second membrane separation unit. ### Claim 15 (depends on 12) An apparatus in accordance with claim 12, wherein the first separation unit is selected from the group consisting of: a partial condenser, an absorption unit, and a pressure swing adsorption unit. ### Claim 16 (depends on 15) An apparatus in accordance with claim 15, wherein the second separation unit is a membrane separation unit. ### Claim 17 (depends on 12) An apparatus in accordance with claim 12, wherein the second separation unit is a membrane separation unit.