JPS58215480A - Heat storage material - Google Patents

Abstract

PURPOSE:To provide a latent heat storage material consisting of calcium chloride, aluminum chloride and water, which performs fusion/freezing cycles at a given temperatures between 0 and 28 deg.C, is least susceptible to overcooling and is capable of repeating heat storage and release consistently for a long period. CONSTITUTION:The heat storage material consists of calcium chloride, aluminum chloride and water. When 40-99.9% CaCl2.6H2O is blended with 0.1-60% AlCl3.6H2O, for example, the freezing point of the material varies within the range of 28-20 deg.C. When water is added in an amount of 7-100wt% of AlCl3. 6H2O, the freezing point is lowered in proportion to the amount of water added. For effective heat storage and release, it is preferable that overcooling is suppressed completely and addition of a nucleator such as strontium oxide, hydroxide, bromide, iodide or phosphate is effective to control the degree of overcooling to 1 deg.C or lower.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat storage phase having a melting point (freezing point) in the range of 15 to 28 nm, which is effective in utilizing solar heat and saving energy.

Solar heat or I'? When 1ull of heat is fully utilized, the energy is stored as latent heat of 1vf of melting of the material, and the so-called latent heat storage material, which is released during solidification, has a large energy storage density 1a'' and is highly effective in terms of energy use. It is also possible to freeze and solidify this heat using late-night electricity and use it for cooling purposes.

Currently, latent heat storage 4A thorns and V1 calcium hexahydrate (CaClt-611tO, melting point, 29.2'C) are the most well-known. Flulucium chloride is conventionally used as a heat source for heating or as a heat pump. However, it can be used for farming purposes, storing solar heat for 5 hours and dissipating it at night to prevent indoor temperatures from dropping by 18'. A greenhouse for cultivation requires a heat storage 4'A material that melts and solidifies in a temperature range of 10 to 20C and stores and releases heat.

In addition, in order to level out power consumption, late-night electricity is used to operate the refrigerator to solidify the heat storage material, which cools the air.
Certain materials are preferred. It is known that the freezing point of calcium chloride hexahydrate decreases when water is added. However, when water is added to CaC1,.6H,0, it melts or solidifies within a certain temperature range and no longer exhibits a fixed melting or freezing point.

Therefore, it cannot be used as a heat storage material for heating or cooling applications that require heat exchange within a narrow temperature range. -! , fc, and a method of adding inorganic salts to change the melting point or freezing point is also known. For example, calcium chloride (CaC1, 6H20) and ferric chloride (FeC1,
-6H20i41: By mixing in a weight ratio of 59, a eutectic mixture with a melting point of 10C is obtained. However, this mixture was highly corrosive and had the disadvantage of severely corroding metals such as copper, aluminum, and iron. In addition, this heat storage material corrodes metals and other materials such as containers, so its composition changes and its melting point changes, making it impossible to use it stably for a long period of time. Magnesium chloride (MgC1,t
-6H2(l lC: a Cz-1" 611!
Addition of 15 to 25 mol% to 0 (also 4i, 20t for compound)
``The melting point is below (# the same point)? I couldn't do it.

This invention is based on calcium chloride hexahydrate (CaC4.6H,0
) is a mixture of aluminum chloride and water, and j
t, calcium chloride, aluminum chloride.

The object of the present invention is to obtain a latent heat storage material that can be melted and solidified at a constant temperature between OC and 28 tT by changing the mixing ratio of water, and can store and release heat stably for a long period of time with little overcooling.

The figure shows the freezing point of a heat storage material whose main components are calcium chloride hexahydrate (CaC4.6H,O) and aluminum chloride by varying the addition of water.

Chloride force Luciuno x (Ca C3I Tatami 6 rig O)
i 40-99.9% l aluminum chloride (Atc
t, φ6 T-I20); By mixing in the range of 0.1 to 60%, the freezing point changes in the range of 28C to 2 (1C.
When 0.00% water is added, the freezing point decreases depending on the amount of water added. ktct, -6H, Oi 52.4%
, CaC4-6H, Oi 47.6% mixture with At
, 7.5, assuming the heavy phase of Cts 6H10 to be 100.
14.9, 22.4゜29.8, 44.7, 59.6,
89.4 addition (this makes AtC1,+7H,0,At
Cl3+8H,0,Atcm+9H,O,AtC1,+
10H20, AtC1, +12H20, ktCl, +
14H20, AtC1, +18) It will contain water equivalent to 120) Then the freezing point will be 2 as shown in the figure.
It drops from 3'C to OC. Mafc, Atct, -6
Similarly, for mixtures with different blending ratios of H, O and C2Cl2.6H,O (CaC4-6H,0; 47°6% to 99.9%), AtCt, +7H,O to ktct, +14
It has been found that by adding water equivalent to H and O, the freezing point decreases as shown by the curve in the figure.

This mixture of aluminum chloride, calcium chloride, and water is a salt of magnesium chloride, manganese chloride, potassium chloride, sodium chloride, ammonium chloride, etc. (i71-3
It can be added in a range of 0%.

These salts have the effect of preventing overcooling of the mixture and stably performing melting and solidification.

Although the heat storage material side 1 of the present invention rarely experiences overcooling, in order to effectively store and release heat, it is preferable that no overcooling occurs at all. For this reason, we investigated methods to prevent overcooling and found that compounds such as strontium oxide, strontium hydroxide, strontium phosphate, strontium hydrogen phosphate, strontium chloride, strontium bromide, strontium iodide, strontium nitrate, etc. It has been found that its hydrates, strontium carbonate and strontium chlorate, are effective and can suppress supercooling to below IC.

Heat storage material 1 of the present invention, as is clear from the figure, OC~28r
m point (#fixed point), Cact, -6H20°A
By changing the mixing ratio of tcts/611tO and water, the melting point can be varied. These mixtures are suitable as heat storage materials that store heat from relatively low-temperature heat sources.In particular, mixtures with a melting point of 10 to 20'C are used to prevent the temperature from dropping in greenhouses, or to store heat from industrial waste heat from low-temperature hot air and hot water. It is suitable for purposes such as collecting and storing heat and using it for heating, etc.

In addition, the mixture with a melting point of OC ~ 10r is used as a cold storage material for cooling, and in order to level out power consumption, late-night electricity is used to create a refrigerator f.
It is suitable for the purpose of operating to solidify the heat storage material, and extracting cold air or cold water from which heat is exchanged to the heat storage material when temperatures rise during the day when electricity demand is high, for use in air conditioning.

As explained above, the heat storage material of the present invention has a heat storage amount of 40 to 4
4 cat/g (specific gravity 1.62 to 2.05), is chemically stable, does not deteriorate even after repeated use, is nonflammable, and does not cause separation. Due to its low price, it can be used for heating (agricultural greenhouses, general heating, melting point 10-28tr) and cooling (melting point 0-Lot?) using solar heat or industrial waste heat.
) is an effective heat storage material for applications such as

[Brief explanation of drawings]

The drawing shows calcium chloride hexahydrate (CaC1, 6H20)
and aluminum chloride, hexahydrate salt (AI Cta・6IT
It is a diagram showing the change in the freezing point when water is added to 2 (Moon and Kot).

Claims (1)

[Scope of Claims] 1° A heat storage material comprising calcium chloride, aluminum chloride, and water. 2. Calcium chloride hexahydrate and aluminum chloride hydrate (
The heat storage material according to claim 1, characterized in that aluminum chloride having a composition corresponding to (6-hydrate to 14-hydrate) and water are added. 3. Strontium oxide or hydroxide as a nucleating material,
The heat storage material according to claim 1 or 2, characterized in that bromide, iodide, phosphate, nitrate, carbonate, and chlorate are added. 4. Calcium chloride (CaC1, 6H, O); 30
~99.9 parts, aluminum chloride (A t Ct8.6
H, O); 0.1 to 70 parts, water i0.007 to 90
A mixture of parts (CaC4-6H,0 and htct, -6H2
The heat storage material according to claim 1, characterized in that the heat storage material is made of a mixture of 0 to Atct, .18H and O).