# US 7,246,506 B2 · Thermal storage medium using a hydrate and apparatus thereof, and method for producing the thermal storage medium > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,246,506 B2 - Document ID: US7246506B2 - Status: Granted - Kind: B2 - Application number: 10/754,049 - Filed: 2004-01-05 - Published: 2005-01-27 - Granted: 2007-07-24 - Earliest claimed: 1999-11-26 - Assignees: JFE Engineering Corporation - Inventors: Shingo Takao; Hidemasa Ogoshi; Shinichiro Fukushima; Shigenori Matsumoto - Web page: https://patentgrep.com/patent/US7246506B2 ## CPC - F28D 20/02: using latent heat - C09K 5/00: Heat-transfer, heat-exchange or heat-storage materials, e.g. refrigerants; Materials for the production of heat or cold by chemical reactions other than by combustion - C09K 5/066: {Cooling mixtures; De-icing compositions} - F28D 20/021: {the latent heat storage material and the heat-exchanging means being enclosed in one container (F28D20/023 - F28D20/028 take precedence)} - F28D 20/023: {the latent heat storage material being enclosed in granular particles or dispersed in a porous, fibrous or cellular structure} - F28F 13/125: {by stirring} - Y02E 60/14: Thermal energy storage - Y02P 20/10: Process efficiency - F28D: HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT (fluid heaters having heat generating means and heat transferring means F24H; furnaces F27; details of heat-exchange apparatus of general) - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - F28F: DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION (water and air traps, air venting F16) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract A thermal storage apparatus for using a hydrate thermal storage medium including: (a) a storage tank for storing a cooling medium liquid; (b) a refrigerating machine, connected with the storage tank via a pipe for cooling the cooling medium liquid, the cooling medium liquid circulating between the storage tank and the refrigerating machine; and (c) a thermal storage body immersed in the cooling medium liquid, wherein the thermal storage medium comprises a hermetically sealed container containing an aqueous solution which generates at least one hydrate selected from the group consisting of a primary hydrate and a secondary hydrate, wherein the primary hydrate has a smaller hydration number and a small heat capacity than the secondary hydrate, and wherein the secondary hydrate has a larger hydration number and a larger heat capacity than the primary hydrate. ## Claims ### Claim 1 A thermal storage apparatus for using a hydrate thermal storage medium comprising: (a) a storage tank for storing a cooling medium liquid; (b) a refrigerating machine, connected with the storage tank via a pipe for cooling the cooling medium liquid, the cooling medium liquid circulating between the storage tank and the refrigerating machine; and (c) a thermal storage body immersed in the cooling medium liquid, wherein the thermal storage medium comprises a hermetically sealed container containing an aqueous solution which generates at least one hydrate selected from the group consisting of a primary hydrate and a secondary hydrate, wherein the primary hydrate has a smaller hydration number and a smaller heat capacity than the secondary hydrate, and wherein the secondary hydrate has a larger hydration number and a larger heat capacity than the primary hydrate. ### Claim 2 (depends on 1) The thermal storage apparatus according to claim 1, wherein the aqueous solution contained in the hermetically sealed container contains a guest compound, and wherein a generation temperature of at least one hydrate selected from the group consisting of the primary hydrate and the secondary hydrate varies in accordance with the concentration of the aqueous solution. ### Claim 3 A hydrate cold thermal storage transporting medium comprising: an aqueous solution containing a guest compound to generate hydrate particles to create a hydrate slurry by cooling; and a corrosion inhibitor having a concentration of 5,000 wt. ppm or less. ### Claim 4 (depends on 3) The hydrate thermal storage medium according to claim 3, wherein the corrosion inhibitor is at least one compound selected from the group consisting of sodium nitrite, sodium sulfite, sodium pyrophosphate and benzotriazole. ### Claim 5 A hydrate thermal storage medium comprising an aqueous solution containing a guest compound which generates by cooling the aqueous solution at least one hydrate selected from the group consisting of a primary hydrate and a secondary hydrate, wherein the primary hydrate has a smaller hydration number and a smaller heat capacity than the secondary hydrate, and wherein the secondary hydrate has a larger hydration number and a larger heat capacity than the primary hydrate. ### Claim 6 (depends on 5) The hydrate thermal storage medium according to claim 5, wherein the guest compound is one compound selected from the group consisting of a tetra-n-butylammonium salt, a tetra-isoamylammonium salt, a tetra-iso-butylphosphonium salt and a tri-iso-amylsulfonium salt. ### Claim 7 A method for producing a hydrate thermal storage medium comprising the steps of: (a) preparing an aqueous solution containing a guest compound; and (b) cooling the aqueous solution to generate at least one hydrate selected from the group consisting of a primary hydrate and a secondary hydrate, wherein the primary hydrate has a smaller hydration number and a smaller heat capacity than the secondary hydrate, and wherein the secondary hydrate has a larger hydration number and a larger heat capacity than the primary hydrate. ### Claim 8 (depends on 7) The method according to claim 7, wherein the aqueous solution is cooled at a rate of 6 kcal/hr-kg or more. ### Claim 9 (depends on 7) The method according to claim 7, wherein the guest compound is contained in the aqueous solution in a concentration of from 10 to 26 wt. %. ### Claim 10 (depends on 7) The method according to claim 7, wherein the aqueous solution is cooled to a temperature range of from 50° C. to 8° C. ### Claim 11 (depends on 7) The method according to claim 7, wherein the guest compound is one compound selected from the group consisting of a tetra-n-butylammonium salt, a tetra-iso-amylammonium salt, a tetra-iso-butylphosphonium salt and a tri-iso-amylsulfonium salt. ### Claim 12 (depends on 7) The method according to claim 7, the aqueous solution is cooled to a generation temperature or less of the secondary hydrate. ### Claim 13 A hydrate thermal storage medium comprising: an aqueous solution contained in a hermetically sealed container to generate at least one hydrate selected from the group consisting of a primary hydrate and a secondary hydrate, wherein the primary hydrate has a smaller hydration number and a smaller heat capacity than the secondary hydrate, and wherein the secondary hydrate has a larger hydration number and a larger heat capacity than the primary hydrate. ### Claim 14 (depends on 13) The thermal storage medium according to claim 13, wherein a guest compound is contained in the aqueous solution in a concentration of 10% to 26%. ### Claim 15 (depends on 13) The thermal storage medium according to claim 13, wherein a guest compound is contained in the aqueous solution, the guest compound being one compound selected from the group consisting of a tetra-n-butylammonium salt, a tetra-iso-amylammonium salt, a tetra-isobutylphosphonium salt and a tri-iso-amylsulfonium salt. ### Claim 16 A hydrate cold thermal storage transporting medium comprising: a primary hydrate and a secondary hydrate, wherein the heat capacity than the secondary hydrate, and wherein the secondary hydrate has a larger hydration number and a larger heat capacity than the primary hydrate. ### Claim 17 (depends on 16) The hydrate cold thermal storage transporting medium according to claim 16, wherein a guest compound is contained in the aqueous solution in a concentration of 10% to 26%. ### Claim 18 (depends on 16) The hydrate cold thermal storage transporting medium according to claim 16, wherein a guest compound is contained in the aqueous solution, the guest compound being one compound selected from the group consisting of a tetra-n-butylammonium salt, a tetra-iso-amylammonium salt, a tetra-isoutylphosphonium salt and a tri-iso-amylsulfonium salt.