# US 5,325,894 A · Method and apparatus for fueling vehicles with liquefied natural gas > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,325,894 A - Document ID: US5325894A - Status: Granted - Kind: A - Application number: 08/117,355 - Filed: 1993-09-07 - Granted: 1994-07-05 - Earliest claimed: 1992-12-07 - Assignees: Chicago Bridge & Iron Technical Services Company - Inventors: Richard J. Kooy; Don H. Coers - Web page: https://patentgrep.com/patent/US5325894A ## CPC - F17C 5/007: {for individual gas tanks or containers, e.g. in vehicles (filling with liquid fuel not under pressure, B60S5/02, B67D7/00)} - F17C 2250/01: Intermediate tanks - F17C: VESSELS FOR CONTAINING OR STORING COMPRESSED, LIQUEFIED OR SOLIDIFIED GASES; FIXED-CAPACITY GAS-HOLDERS; FILLING VESSELS WITH, OR DISCHARGING FROM VESSELS, COMPRESSED, LIQUEFIED, OR SOLIDIFIED GASES (storing fluids in natural or artificial cavities or chambers in the earth B65G5/00; construction or assembling of bulk storage containers employing civil-engineering techniques E04H7/00; variable-capacity gas-holders F17B; liquefaction or refrigeration machines, plants, or systems F25) ## Abstract Apparatus for, and a method of, withdrawing liquefied natural gas stored in a primary insulated storage tank at a low pressure and at a temperature close to its boiling point; increasing the pressure of the withdrawn liquefied natural gas and then feeding the pressurized liquefied natural gas through a heat exchanger to warm the liquefied natural gas to a subcooled or near saturated liquid condition at a temperature of about -220.degree. F. to -126.degree. F. when at a pressure of about 50 psig to 550 psig; and feeding the said warmed and pressurized liquefied natural gas to an insulated tank on a vehicle at a refueling facility, said vehicle using liquefied natural gas as its fuel and the insulated vehicle fuel tank being adapted to safely contain and store the said liquefied natural gas in liquid form, at an approximate saturated condition at a temperature of about -220.degree. F. to -126.degree. F. and a pressure of about 50 psig to 550 psig. ## Claims ### Claim 1 A method comprising: withdrawing liquefied natural gas stored in a primary insulated storage tank at a low pressure and at a temperature close to its boiling point; increasing the pressure of the withdrawn liquefied natural gas and then feeding the pressurized liquefied natural gas through a heat exchanger to warm the liquefied natural gas to a subcooled or near saturated liquid condition at a temperature of about -220.degree. F. to -126.degree. F. when at a pressure of about 50 psig to 550 psig; and feeding the said warmed and pressurized liquefied natural gas to an insulated tank on a vehicle at a refueling facility, said vehicle using liquefied natural gas as its fuel and the insulated vehicle fuel tank being adapted to safely contain and store the said liquefied natural gas in liquid form, at an approximate saturated condition at a temperature of about -220.degree. F. to -126.degree. F. and a pressure of about 50 psig to 550 psig. ### Claim 2 (depends on 1) A method according to claim 1 in which: natural gas vapor accumulates in the primary insulated storage tank; and natural gas vapor is withdrawn from the primary insulated storage tank and is combined with the liquefied natural gas withdrawn from the primary insulated storage tank, after the pressure on the withdrawn liquefied natural gas has been increased, to form a combined stream which is fed through the heat exchanger. ### Claim 3 (depends on 1) A method according to claim 1 in which: some of the liquid natural gas withdrawn from the primary storage tank and then increased in pressure is mixed with the warmed and pressurized liquefied natural gas exiting the heat exchanger and the resulting mixture is fed to the vehicle tank. ### Claim 4 (depends on 1) A method according to claim 1 in which the liquefied natural gas in the primary insulated storage tank is at about 15 psia to 45 psia and a temperature of about -258.degree. F. to -230.degree. F. ### Claim 5 (depends on 1) A method according to claim 1 in which: the heat exchanger is a direct contact heat exchanger and the pressurized liquefied natural gas is warmed therein by direct contact with vapor withdrawn from the primary insulated storage tank. ### Claim 6 A method comprising: withdrawing liquefied natural gas stored in a primary insulated storage tank at a low pressure and at a temperature close to its boiling point; increasing the pressure of the withdrawn liquefied natural gas and the feeding the pressurized liquefied natural gas through a heat exchanger to warm the liquefied natural gas to a near saturated liquid condition at a temperature of about -220.degree. F. to -126.degree. F. when at a pressure of about 50 psig to 550 psig; feeding the warmed and pressurized liquefied natural gas from the heat exchanger to a stationary insulated natural gas dispensing tank located at a vehicle liquefied natural gas refueling facility and storing the liquefied natural gas in the dispensing tank in an approximate saturated condition at a temperature of about -220.degree. F. to -126.degree. F. and a pressure of about 50 psig to 550 psig; and upon arrival of a vehicle at the refueling facility, said vehicle using liquefied natural gas as its fuel and being equipped with an insulated vehicle tank adapted to safely contain and store liquefied natural gas in liquid form, transferring liquefied natural gas from the dispensing tank to the vehicle fuel tank so that the liquefied natural gas is in an approximate saturated condition at a temperature of about -220.degree. F. to -126.degree. F. and a pressure of about 50 psig to 550 psig. ### Claim 7 (depends on 6) A method according to claim 6 in which: the liquefied natural gas is delivered to the vehicle tank without a substantial change in temperature and pressure from that at which it is stored in the dispensing tank. ### Claim 8 (depends on 6) A method according to claim 6 in which: natural gas vapor accumulates in the primary insulated storage tank; and natural gas vapor is withdrawn from the primary insulated storage tank and is combined with the liquefied natural gas withdrawn from the primary insulated storage tank, after the pressure on the withdrawn liquefied natural gas has been increased, to form a combined stream which is fed through the heat exchanger. ### Claim 9 (depends on 6) A method according to claim 6 in which: vapor forms in the dispensing tank and the vapor is returned to the primary insulated storage tank. ### Claim 10 (depends on 6) A method according to claim 6 in which: some of the liquefied natural gas withdrawn from the primary storage tank and then increased in pressure is fed into admixture with liquefied natural gas withdrawn from the dispensing tank to form a blended mixture having a controlled temperature and pressure which is fed to the vehicle tank. ### Claim 11 (depends on 6) Amethod according to claim 6 in which: some of the liquefied natural gas withdrawn from the primary storage tank and then increased in pressure is fed into admixture with the warmed and pressurized liquefied natural gas from the heat exchanger, and then the resulting blended admixture is fed to the dispensing tank. ### Claim 12 Apparatus comprising: a primary insulated storage tank containing liquefied natural gas at a pressure close to atmospheric pressure and at a temperature close to its boiling point; a heat exchanger; a first conduit communicating with the liquefied natural gas in the primary tank and with the heat exchanger, said conduit including a pump, for withdrawing liquefied natural gas from the primary tank, increasing the pressure of the withdrawn liquefied natural gas and feeding it to the heat exchanger wherein the pressurized liquefied natural gas is warmed to a temperature no more than about -220.degree. F. to -126.degree. F. when at a pressure of about 50 psig to 550 psig; a vehicle using liquefied natural gas as its fuel and having an insulated fuel tank on board for receiving liquefied natural gas; and a second conduit communicating with the heat exchanger and the vehicle fuel tank for receiving the warmed and pressurized liquefied natural gas from the heat exchanger and feeding it to the vehicle fuel tank for storage as a liquid therein at a temperature of about -220.degree. F. to -126.degree. F. and a pressure of about 50 psig to 550 psig and at an approximate saturated condition. ### Claim 13 (depends on 12) Apparatus according to claim 12 in which: the primary storage tank has a natural gas vapor space; and a natural gas vapor withdrawal conduit communicates with the primary tank vapor space and with the conduit communicating with the primary tank and with the heat exchanger. ### Claim 14 (depends on 12) Apparatus according to claim 12 comprising: a third conduit communicating with the first conduit and the second conduit for admixing streams of liquefied gas to be fed through the first and second conduits to the third conduit to form an admixed stream and for delivering the admixed stream to the vehicle fuel tank. ### Claim 15 (depends on 12) Apparatus according to claim 12 in which: the heat exchanger is a direct contact heat exchanger and the pressurized liquefied natural gas is warmed therein by direct contact with vapor withdrawn from the primary insulated storage tank. ### Claim 16 Apparatus comprising: a primary insulated storage tank containing liquefied natural gas at a pressure close to atmospheric pressure and at a temperature close to its boiling point; a heat exchanger; a first conduit communicating with the liquefied natural gas in the primary tank and with the heat exchanger, said conduit including a pump, for withdrawing liquefied natural gas from the primary tank, increasing the pressure of the withdrawn liquefied natural gas and feeding it to the heat exchanger wherein the pressurized liquefied natural gas is warmed to a temperature of about -220.degree. F. to -126.degree. F. when at a pressure of about 50 psig to 550 psig and so that the liquefied natural gas is at an approximate saturated condition; a stationary insulated natural gas dispensing tank located at a vehicle liquefied natural gas refueling facility; a second conduit for feeding the warmed and pressurized liquefied natural gas from the heat exchanger to the stationary insulated natural gas dispensing tank for storage in the said dispensing tank at an approximate saturated condition and at a temperature of about -220.degree. F. to -126.degree. F. and a pressure of about 50 psig to 550 psig; a vehicle using liquefied natural gas as its fuel and having an insulated fuel tank on board for receiving liquefied natural gas; and a third conduit communicating with the dispensing tank and the vehicle fuel tank for receiving warmed and pressurized liquefied natural gas from the dispensing tank and feeding it to the vehicle fuel tank for storage therein at a temperature of about -220.degree. F. to -126.degree. F. and a pressure of about 50 psig to 550 psig and at an approximate saturated condition. ### Claim 17 (depends on 16) Apparatus according to claim 16 in which: the primary storage tank has a natural gas vapor space; and a natural gas vapor withdrawal conduit communicates with the primary tank vapor space and with the conduit communicating with the liquefied natural gas in the primary tank and with the heat exchanger for combining the vapor with the liquefied natural gas. ### Claim 18 (depends on 16) Apparatus according to claim 16 including: a fourth conduit communicating with the first conduit and the third conduit for feeding pressurized liquefied natural gas into admixture with warm liquefied natural gas withdrawn from the dispensing tank to thereby form a blended stream of liquefied natural gas to feed to the vehicle tank. ### Claim 19 (depends on 16) Apparatus according to claim 16 including: conduit means for withdrawing natural gas vapor from the dispensing tank and returning it to the primary storage tank. ### Claim 20 (depends on 16) Apparatus according to claim 16 comprising: a fourth conduit communicating with the first conduit and with the second conduit for feeding pressurized liquefied natural gas into admixture with warm liquefied natural gas withdrawn from the heat exchanger to thereby form a blended stream of liquefied natural gas to feed to the dispensing tank.