# US 2014/0150491 A1 · Use of low global-warming potential, low ozone depletion potential, low combustibility hydrofluoro-olefin, xenon or iodo compound refrigerants in lng processing > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0150491 A1 - Document ID: US20140150491A1 - Status: Published application - Kind: A1 - Application number: 14/085,372 - Filed: 2013-11-20 - Published: 2014-06-05 - Earliest claimed: 2012-12-04 - Assignees: ConocoPhillips Company - Inventors: Paul DAVIES; James Lee HARRIS, JR.; Emery Jay THOMAS; Gregg SAPP - Web page: https://patentgrep.com/patent/US20140150491A1 ## CPC - F25J 1/0022: {Hydrocarbons, e.g. natural gas} - C09K 5/042: {comprising compounds containing carbon and hydrogen only} - C09K 5/045: {containing only fluorine as halogen} - F25J 1/0062: {Light or noble gases, mixtures thereof (F25J1/007 takes precedence)} - F25J 1/0097: {Others, e.g. F-, Cl-, HF-, HClF-, HCl-hydrocarbons etc. or mixtures thereof} - F25J 1/0256: {Safety aspects of operation (F25J1/0298 takes precedence)} - F25J 1/0278: {Unit being stationary, e.g. on floating barge or fixed platform} - C09K 2205/126: Unsaturated fluorinated hydrocarbons - F25J: LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS {OR LIQUEFIED GASEOUS} MIXTURES BY PRESSURE AND COLD TREATMENT {OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE (cryogenic pumps F04B37/08; gas storage vessels, gas holders F17; filing vessels with, or discharging from vessels, compressed, liquefied or solidified gases F17C; refrigeration machines, plants, or systems F25B)} - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE ## Abstract Methods and systems for liquefying natural gas using environmentally-friendly low combustibility refrigerants are provided. Methods of liquefaction include cooling a fluid in an LNG facility via indirect heat exchange with an environmentally-friendly low combustibility refrigerant selected from the group consisting of: a fluorinated olefin, xenon, any derivative thereof, and any combination thereof. ## Claims ### Claim 1 A method for liquefying natural gas comprising: cooling a fluid in an LNG facility via indirect heat exchange with an environmentally-friendly low combustibility refrigerant selected from the group consisting of: a fluorinated olefin, any derivative thereof, and any combination thereof. ### Claim 2 (depends on 1) The method of claim 1 wherein the fluorinated olefin includes 2 to about 10 carbons. ### Claim 3 (depends on 1) The method of claim 1 wherein the fluid is a natural gas stream or a refrigerant. ### Claim 4 (depends on 3) The method of claim 3 wherein the refrigerant is selected from the group consisting of: propane, ethylene, methane, and any combination thereof. ### Claim 5 (depends on 1) The method of claim 1 wherein the fluorinated olefin is selected from the group consisting of: difluoroethylene, hexafluoropropene and tetrafluoroethene. ### Claim 6 (depends on 1) The method of claim 1 wherein the environmentally-friendly low combustibility refrigerant is used to pre-cool a mixed refrigerant. ### Claim 7 (depends on 6) The method of claim 6 wherein the mixed refrigerant comprises at least one of: nitrogen, methane, ethane, and propane. ### Claim 8 (depends on 1) The method of claim 1 wherein the environmentally-friendly low combustibility refrigerant is used in an optimized cascade process. ### Claim 9 (depends on 8) The method of claim 8 wherein the environmentally-friendly low combustibility refrigerant is used as a first refrigerant during a first refrigeration cycle. ### Claim 10 (depends on 1) The method of claim 1, further comprising producing liquefied natural gas. ### Claim 11 (depends on 10) The method of claim 10, further comprising: vaporizing the liquefied natural gas. ### Claim 12 A method for liquefying natural gas comprising: cooling a fluid in an LNG facility via indirect heat exchange with an environmentally-friendly low combustibility refrigerant comprising: a fluorinated olefin and a paraffinic fluorocarbon. ### Claim 13 (depends on 12) The method of claim 12 wherein the fluorinated olefin is present in about 0.1% to about 99% by volume. ### Claim 14 (depends on 12) The method of claim 12 wherein the fluorinated olefin includes about 2 to about 10 carbons. ### Claim 15 (depends on 12) The method of claim 12 wherein the paraffinic fluorocarbon includes about 2 to about 10 carbons. ### Claim 16 (depends on 12) The method of claim 12 wherein the fluid is a natural gas stream or a refrigerant. ### Claim 17 (depends on 16) The method of claim 16 wherein the refrigerant is selected from the group consisting of: propane, ethylene, methane, and any combination thereof. ### Claim 18 (depends on 12) The method of claim 12 wherein the fluorinated olefin is selected from the group consisting of: difluoroethylene, hexafluoropropene, tetrafluoroethene, any derivative thereof, and any combination thereof. ### Claim 19 (depends on 12) The method of claim 12 wherein the paraffinic fluorocarbon is selected from the group consisting of: difluoromethane, pentafluoromethane, trifluoromethane, hexafluoroethane, any derivative thereof, and any combination thereof. ### Claim 20 (depends on 12) The method of claim 12 wherein the refrigerant mixture is used to pre-cool a mixed refrigerant. ### Claim 21 (depends on 20) The method of claim 20 wherein the mixed refrigerant comprises at least one of: nitrogen, methane, ethane, and propane. ### Claim 22 (depends on 12) The method of claim 12 wherein the refrigerant is used in an optimized cascade LNG process. ### Claim 23 (depends on 22) The method of claim 22 wherein the environmentally-friendly low combustibility refrigerant is used as a first refrigerant during a first refrigeration cycle. ### Claim 24 (depends on 23) The method of claim 23, further comprising producing liquefied natural gas. ### Claim 25 (depends on 24) The method of claim 24, further comprising: vaporizing the liquefied natural gas. ### Claim 26 A method for liquefying natural gas comprising: cooling a fluid in an LNG facility via indirect heat exchange with an environmentally-friendly low combustibility refrigerant selected from the group consisting of: xenon, a mixture of xenon and a fluorocarbon, a mixture of xenon and ethylene, a mixture of xenon and a hydrocarbon, a mixture of xenon and an iodine substituted fluorohydrocarbon, a mixture of xenon and a fluorolefin refrigerant mixture, any derivative thereof, and any combination thereof.