JPS6114283A - Thermal energy storage material composition - Google Patents

Abstract

PURPOSE:To provide a thermal energy storage material compsn. which can be repeatedly used and dissipates heat only when required, containing a salt hydrate which can be supercooled and emits latent heat in the transition from a high- temperature phase to a low-temperature phase, and a hydroxylpropylated guar gum. CONSTITUTION:The titled thermal energy storage material contains a salt hydrate (A) (e.g. calcium chloride hexahydrate or sodium carbonate decahydrate) which can be supercooled and emits latent heat in the transition from a high- temperature phase to a low-temperature phase, and 0.2-1.5wt% (based on the quantity of compsn.) hydroxypropylated guar gum (B) as essential ingredients. The compsn. accumulates latent heat by heating and retains the latent heat in a supercooling state at room temp. When required, a seed crystal is added thereto, or a stimulus is given to the compsn. by a sharp metal stick to thereby break supercooling, whereby latent heat is dissipated. In this way, the heating and the breaking of supercooling are repeatedly made, whereby thermal energy storage and heat dissipation can be repeated.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an M heating agent composition.

In particular, the present invention relates to a reusable heat storage agent composition that can retain latent heat accumulated through heating in a supercooled state and, when necessary, destroy the supercooling and extract the accumulated latent heat. .

[Conventional technology]

Various latent heat storage agents have been developed for storing heat such as solar energy, but most of them are used in systems that prevent supercooling. However, heat storage agents that utilize supercooling are known per se; for example, US Pat. No. 4,077,390 describes a heat storage puncture using sodium acetate trihydrate. Further, JP-A-59-53578 describes a heat storage body containing sodium acetate trihydrate and xanthan gum.

[Problem that the invention seeks to solve]

As described in U.S. Pat. No. 4,077,390,
When using an aqueous solution of sodium acetate trihydrate as is, crystals attached to the lid of the container may fall into the supercooled system due to vibrations, etc., and the supercooling may be destroyed at an unnecessary time ( However, it has the disadvantage that it cannot be said to be a stable system.

Furthermore, the composition described in JP-A No. 59-53578 is
Although this is an improvement on the above points, it has the disadvantage that the gum and inorganic salts, etc. separate due to repeated heating and heat radiation, reducing the effect of adding gum.

An object of the present invention is to provide a latent heat storage agent that can protect against supercooling with the necessary special stability and can be used repeatedly.

(Means for Solving the Problems) The M heat agent composition of the present invention includes, as an essential component, a salt hydrate that can be supercooled and releases latent heat when transferring from a high temperature phase to a low temperature phase; It contains hydroxypropylated guar gum.

Hereinafter, the heat storage agent composition of the present invention will be explained in detail.

Salt hydrates that can be supercooled and release latent heat when transferring from a high temperature phase to a low temperature phase used in the present invention include, for example, calcium chloride hexahydrate (melting point 29°C), sodium carbonate decahydrate (melting point 35°C), disodium phosphate decahydrate (melting point 35.5°C), calcium nitrate tetrahydrate (melting point 42.7°C), sodium sulfate decahydrate (melting point 32°C),
), sodium thiosulfate pentahydrate (melting point 50°C), sodium acetate trihydrate (melting point 5°8°C), barium hydroxide octahydrate (melting point 35°C), zinc nitrate hexahydrate ( Melting point 5
0°C), potassium fluoride tetrahydrate. (melting point 18.5℃)
etc., and it is sufficient to select and use a material with a melting point depending on the purpose. These salt hydrates constitute the main body of the heat storage agent composition of the present invention, and usually make up 90% of the composition.
It accounts for more than % by weight.

Examples of the hydroxypropylated guar gum used in the present invention include Jaguar HP manufactured by Niksho Co., Ltd., and products with a substitution degree of 0.3 to 0.6 per constituent sugar include Jaguar HP- 8. Jaguar HP -1'
1 and Jaguar HP-60.

The amount of hydroxypropylated guar gum to be used may be determined by considering the viscosity of the required heat storage agent composition, etc.
Usually, the amount is about 0.2% to 1.5% by weight (the amount that makes the viscosity about 50cp to 10,000cp), preferably about 0.3% to 0.6% by weight (viscosity of about 70 cp to 500 cp). still,
The heat storage agent composition of the present invention has a viscosity within the above range, that is, 50
cp~10000cp, preferably 70cp~500C
It is preferable to adjust the temperature to 11 from the viewpoint of stably maintaining the supercooled state.

In addition, the supercooled state of the heat storage agent composition of this invention
1. In addition to the above two essential components, the composition may contain 1 to 5% by weight of a polyhydric alcohol with a melting point of 80° C. or less, such as propylene glycol, ethylene glycol, glycerin, etc., in order to maintain the stability. It is preferable to add water, a disinfectant, a coloring agent, etc., if necessary.

The heat storage agent composition of the present invention is not particularly limited in its manufacturing method, and can be manufactured, for example, by a method as shown in Examples below.

[Effect]

At room temperature, the heat storage agent composition of the present invention retains the latent heat accumulated through heating in a stable supercooled state, and when the supercooled state is broken, the latent heat is released. By repeating this, the heat storage and heat dissipation effects described above are repeatedly performed.

〔Example〕

Examples of the present invention are shown below, but the present invention is not limited thereto.

Example 1 19.4 g of distilled water was added to a 300 ml separable flask equipped with a stirrer and a condenser and a temperature needle, and the mixture was heated to 80°C.
Installed in the water pass. While stirring with a stirrer, 1.2 g of hydroxypropylated guar gum (trade name: Jaguar HPJ Sansho Co., Ltd.) was gradually added to the distilled water, and the mixture was uniformly dispersed and dissolved without forming lumps to obtain a viscous solution. . Next, 120.6 g of anhydrous sodium acetate was added to this viscous solution, and the mixture was heated to 80° C. with sufficient stirring until the solid particles were completely dissolved and a homogeneous transparent viscous solution was obtained. . At this time, a water cooler was used to prevent water loss.

The above clear viscous solution was transferred to a 300 ml clear thick-walled glass bottle with a screw cap and the bottle was slowly cooled to room temperature. Crystallization of the mixture was induced by introducing hydrate seed crystals or by stimulating with a pointed metal rod.As a result, the mixture (heat storage agent composition) immediately released its latent heat. The temperature rose to 55°C.

The above mixture was heated again to 80° C. until it became a homogeneous, transparent, viscous solution again, and then slowly cooled to room temperature again. This mixture was able to induce crystallization again as before, giving off latent heat and rising to 55°C. This operation was repeated 60 times, but the same result was obtained.

Furthermore, even after repeating the same operation 60 times, the color tone of this mixture hardly changed, and when it was made into a viscous solution at 80°C, there was no aggregation or separation of the hydroxypropylated guar gum, and it maintained a good consistency. Ta.

Further, this viscous solution was allowed to cool down and then 10.0
After standing for a day, the mixture was seeded with sodium acetate trihydrate seed crystals or stimulated with a pointed metal rod, causing the mixture to suddenly rise in temperature to 55°C. The mixture was then warmed again to 80° C. and cooled again to room temperature as a clear viscous solution. When this mixture was given the same stimulus as above, similar results were obtained.

Example 2 Using the apparatus used in Example 1, 1.6 g of hydroxypropylated guar gum was placed in a 300 ml flask, 16 g of propylene glycol was added thereto, the hydroxypropylated guar gum was wet-dispersed, and the mixture was stirred. While stirring, add 79.4 g of distilled water, and add 79.4 g of distilled water while stirring.
After heating to 0° C. to form a uniform, transparent solution, 120.6 g of anhydrous sodium acetate was added thereto, and the mixture was stirred until completely melted to form a uniform, transparent, viscous solution. At this time, water cooling was used to prevent water loss.

The above clear viscous solution was transferred to a thick-walled glass bottle with a screw cap in the same manner as in Example 1, and slowly cooled to room temperature. The mixture thus obtained (heat storage agent composition) was stimulated in the same manner as in Example 1 to induce crystallization of the mixture.

As a result, the mixture (M execution composition) immediately gave off its latent heat and rose to 55°C.

The above mixture containing approximately 7.4% by weight of propylene glycol was not induced by the force of falling from the glass wall while moving, but was
ゝIt was triggered when I pressed hard in 1.

This mixture was repeatedly dissolved, solidified, and induced 60 times in the same manner as in Example 1, and the same results as in Example 1 were obtained. There was no aggregation or separation of the hydroxypropylated guar gum, and good consistency was maintained.

Furthermore, induction was performed after the mixture was kept at room temperature for 100 days as in Example 1, but the temperature of the mixture rose to 55° C. immediately after induction. Thereafter, this mixture was repeatedly melted, solidified, and induced 10 times, all raising the temperature to 55°C.

〔Effect of the invention〕

At room temperature, the heat storage agent composition of the present invention retains the latent heat accumulated through heating in a stable supercooled state, and when the supercooled state is broken, the latent heat is released. By repeating (melting, solidifying and inducing the mixture) 1. Since the above-mentioned heat storage and heat dissipation actions are performed repeatedly, the heat storage agent composition of the present invention can extract latent heat when necessary, there is no risk of heat dissipation when unnecessary, and it can be used repeatedly. be.

Claims (1)

[Claims] A supercoolable heat storage agent composition containing as essential constituents a salt hydrate that is supercoolable and releases latent heat when transferring from a high temperature phase to a low temperature phase, and hydroxypropylated guar gum.