Thermal energy storage composition comprising sodium sulfate decahydrate; sodium carbonate decahydrate; and sodium tetraborate decahydrate

• US 4,292,189 A
• Filed: 07/30/1979
• Issued: 09/29/1981
• Est. Priority Date: 07/30/1979
• Status: Expired due to Term

• Current Assignee: ATOFINA Chemicals, Inc. (Arkema)
• Original Assignee: Pennwalt Corporation (Arkema)
• Inventors: Chen, Johnson C.
• Primary Examiner(s): PITLICK, HARRIS
• Application Number:
  US06/061,590
• Time in Patent Office: 792 Days
• Field of Search: 252/70, 126/400, 126/900, 126/430, 126/436
• US Class Current: 252/70
• CPC Class Codes: C09K 5/063 Materials absorbing or liberating heat during crystallisation; Heat storage materials

Abstract

A thermal energy storage composition is disclosed that stores heat upon melting and releases heat upon solidification. It is composed of a mixture of sodium sulfate decahydrate, sodium carbonate decahydrate, sodium borate decahydrate and a thickening agent. Its good heat transfer characteristics, relatively high latent heat of fusion, low cost, and favorable melting point allow this material to be particularly useful for space heating applications.

Claims

1. A composition for storing and releasing thermal energy consisting essentially of the following ingredients expressed in percent by weight:

sodium sulfate decahydrate--about 30-50%,

sodium carbonate decahydrate--about 50-60%,

sodium borate decahydrate--about 1-10% and

a thickening agent--about 0.5 to 8%,

wherein the composition melts and freezes within the range of 21°

to 24°

centrigrade.

2. The composition of claim 1 in which the sodium sulfate decahydrate is present at 40%, the sodium carbonate decahydrate is present at 55% and the sodium borate decahydrate is present at 5 percent.

3. The composition of claim 1 in which the thickening agent is fumed silica at a concentration of 3 percent.