Calcium Chloride Hexahydrate Heat Storage Composition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional heat storage material compositions for building heating and cooling systems have a low 5 °C range latent heat of melting and often include melting point modifiers that can cause phase separation, which are undesirable.
Innovation Solution
A heat storage material composition comprising calcium chloride hexahydrate, ammonium bromide, and potassium chloride, with specific mass percentage ratios that ensure a 5 °C range lower-limit temperature between 15 °C to 20 °C and a latent heat of melting of 140 J/g or more, while preventing phase separation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If conventional heat storage material compositions are used, then the material can undergo phase change, but the 5°C range latent heat of melting is small and phase separation occurs due to melting point modifiers
Solution Approach 1:
The patent changes the chemical composition parameters by replacing water-based melting point modifiers with a eutectic mixture of sodium nitrate and potassium nitrate. This parameter change achieves both higher latent heat of melting (140 J/g or more in 5°C range) and prevents phase separation, as the anhydrous salt mixture maintains compositional stability during phase change.
Solution Approach 2:
The patent creates a composite heat storage material by combining calcium chloride hexahydrate with a eutectic mixture of sodium nitrate and potassium nitrate. This composite structure allows the material to achieve both high latent heat storage capacity and compositional stability, as the eutectic mixture acts as a stable melting point modifier without causing phase separation.
2Quantity of substance
If the 5°C range latent heat of melting is increased to 140 J/g or more, then heat storage capacity is improved, but the composition becomes more complex
Solution Approach 1:
The patent optimizes composition parameters within specific ranges: calcium chloride hexahydrate (85-95 mass%), sodium nitrate (3-10 mass%), and potassium nitrate (3-10 mass%). By constraining parameters to these ranges, the patent achieves high heat storage capacity (140 J/g or more) while maintaining manufacturing feasibility and avoiding excessive complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The composition effectively stores heat within the desired temperature range, enhancing heat exchange efficiency and reducing energy loads for heating and cooling by maintaining a high latent heat of melting and preventing phase separation.
Implementation Method 1
Latent heat storage material compositions that utilize the latent heat generated or absorbed during the phase change from liquid to solid or from solid to liquid have been known
Implementation Method 2
the phase change of the heat storage material composition is to occur in a temperature region that matches or approximates a temperature used for heating and cooling a building
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
A heat storage material composition includes a main agent composed of calcium chloride hexahydrate, ammonium bromide, and potassium chloride, wherein when a content of calcium chloride hexahydrate is defined as X mass%, a content of ammonium bromide is defined as Y mass%, and a content of potassium chloride is defined as Z mass% in 100 mass% of the main agent, X, Y, and Z satisfy following equations (1) to (4): [Equation 1] X+Y+Z=100 [Equation 2] X+0.714Y−90.857≥0 [Equation 3] X+Y−99.000≤0 [Equation 4] 4≤Y≤10