Methods for storing and releasing thermal energy, associated reactor and application to the interseasonal storage of solar heat

Patent metadata

Field	Value
Publication number	US-9618276-B2
Application number	US-201314426079-A
Country	US
Kind code	B2
Filing date	Aug 28, 2013
Priority date	Sep 4, 2012
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

The invention concerns a method for storing or releasing thermal energy by chemical reaction according to which a flow of heat-transfer gas is circulated through a layer ( 10 ) of a first hygroscopic salt A, then through a layer ( 20 ) of a second hygroscopic gas B, the gas being reactive with salts A and B, the thermodynamic equilibrium curve of salt A being located further to the left than that of second salt B in a pressure-temperature phase diagram, the circulation of the flow of gas causing a dehydration or hydration reaction of both first salt A and second salt B.

First claim

The invention claimed is:

1. A process for storing thermal energy by chemical reaction wherein a flow of heat transfer gas is circulated through a layer of a first hygroscopic salt A then through a layer of a second hygroscopic salt B, the gas being reactive with the salts A and B, the thermodynamic equilibrium curve of the salt A being located further to the left than that of the second salt B in a pressure-temperature phase diagram, the circulation of the flow of gas giving rise to a dehydration or hydration reaction both of the first salt A and of the second salt B; wherein the first salt A is selected from the double sulfate of aluminum and potassium (KA1(S04)2), strontium hydroxide Sr(OH)2, sodium sulfide Na2S and ammonium aluminum sulfate NH4A1(S04)2, while the second salt B is respectively selected from strontium bromide (SrBr2), sodium sulfide (Na2S), and nickel sulfate (NiS04).

2. The process for storing or releasing thermal energy as claimed in claim 1 , wherein the flow of gas is a flow of moist air.

3. The process for storing and releasing thermal energy as claimed in claim 1 wherein the circulation of the flow of moist air that gives rise to the dehydration reaction takes place, through the salts, in the same direction as that which gives rise to the hydration reaction.

4. The process for storing and releasing thermal energy as claimed in claim 1 , wherein the circulation of the flow of moist air that gives rise to the dehydration reaction takes place, through the salts, in the opposite direction to that which gives rise to the hydration reaction.

5. An application of the process as claimed in claim 1 to an interseasonal storage of solar heat.

Assignees

• Commissariat Energie Atomique
• Commissariat à l'Energie Atomique et aux Energies Alternatives

Inventors

• Tanguy Gwennyn
• Marias Foivos-Epameinon
• Wyttenbach Joël

Classifications

• Y02E60/14

  Thermal energy storage · CPC title

• F28D20/0043

  specially adapted for long-term heat storage; Underground tanks; Floating reservoirs; Pools; Ponds (F28D20/0052 takes precedence) · CPC title

• Y02E60/142

  Cross-Sectional Technologies · mapped topic

• F28D20/003 Primary

  using thermochemical reactions · CPC title

• F28D2020/0082

  Multiple tanks arrangements, e.g. adjacent tanks, tank in tank · CPC title