JP2005298534A - Heat storage material and heat storage system using heat storage material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat storage material excellent in stability as a dispersion and stable even after repeated solidification and melting, and a heat storage apparatus or a heat storage system suitably employable for the purposes of power saving and efficiency increase of air conditioning energy, protection of the environment, or the like. <P>SOLUTION: The heat storage material comprises as essential ingredients an oily substance exhibiting heat storage properties by phase changes, an aqueous medium and a dispersant, where the heat storage material contains metal elements belonging to the third and/or fourth period. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a heat storage body and a heat storage device or a heat storage system. More specifically, a heat storage body comprising an aqueous dispersion that essentially requires an oily substance having heat storage properties due to phase change, and the heat storage body for heat in a large-scale building such as an office building or factory, or a home-use air conditioner. The present invention relates to a heat storage device or a heat storage system used in a storage system.

Aliphatic hydrocarbons, fatty acids, and fatty acid esters are known as oil-based heat storage materials using latent heat. These oil-based heat storage materials have the property of releasing heat during the phase change from solid to liquid and absorbing heat during the phase change from liquid to solid. This can be used in heat storage systems to save energy and improve efficiency of heating and cooling energy. Attention has been focused on technologies that are intended to be utilized for the purpose of environmental protection and environmental protection. For example, as a heat storage device using a heat storage body containing an oil-based heat storage material, the heat storage body is cooled and solidified by circulating the heat storage body between the heat storage tank and the refrigerator, and the heat absorption effect at the time of melting is utilized for cooling. What you are trying to do is being used.

As a method of effectively using a conventional oil-based heat storage material, an oil-in-water emulsion using a surfactant, a method of retaining an oil-based heat storage material inside a lipophilic polymer particle, an oil-based heat storage in a microcapsule The method of enclosing a substance is mentioned. In addition, after making into an oil-in-water emulsion using a surfactant, the emulsion is prevented from collapsing (separation of water and oil-based heat storage material) due to repeated solidification / melting due to phase change of the heat storage body. Means may be used in which the oil-based heat storage material is held inside the oil-based polymer particles, or the oil-based heat storage material is included in the microcapsules.

By the way, as what exhibits heat storage performance, the heat storage material which consists of an emulsion which consists of paraffin, water, and surfactant is disclosed (for example, refer patent document 1). If such a heat storage material can stably exhibit heat storage performance, it can be effectively used in a heat storage system that repeats solidification / melting, saving energy and increasing efficiency of air conditioning energy. This is useful for environmental protection and other purposes. However, since there has been no study for improving the stability of the emulsion that constitutes the heat storage material, the component of the heat storage material has room for improvement.
Moreover, the thermal storage agent for an air conditioning which consists of hydrocarbon, surfactant, and water is disclosed (for example, refer patent document 2). An example of an air conditioning system using this heat storage agent for air conditioning is described. However, even in such a heat storage agent, in order to improve the stability of the heat storage agent, there is room for contrivance regarding the components of the heat storage agent. If the stability of the heat storage agent is reduced, the oil-based heat storage material will be separated during repeated solidification / melting and cannot be used effectively in the heat storage system. There is a need to improve performance.

JP 57-40582 A (page 1-2) JP-A-9-255944 (page 1-3)

The present invention has been made in view of the above-mentioned present situation, and is excellent in stability as a dispersion and stable even by repeated use of solidification / melting, and energy saving and efficiency improvement of air conditioning energy, environmental protection It is an object of the present invention to provide a heat storage device or a heat storage system that can be suitably used for such purposes.

The inventors of the present invention have made various studies on a heat storage body having heat storage properties by phase change, and it is stable when the heat storage body including an oily substance, an aqueous medium, and a dispersant is used in the presence of a metal element, and the third period. And / or it has been found that the stability is improved in the presence of the metal element of the fourth period. In other words, it was found that when the oily substance dispersion was repeatedly solidified / melted by phase change in a state where the metal was present in the dispersion in which the oily substance was dispersed in an aqueous medium, the oily substance was stable. Normally, in a dispersion dispersed in an aqueous medium, it was thought that the dispersion would become unstable if a metal element was present. However, in the form of the heat storage body of the present invention, in the presence of the metal element. Is also found to be stabilized. When a heat storage body is used in a heat storage system, it will be used in a state where the dispersion flows in various pipes, but when metal is used in the pipes, the metal flows out into the dispersion. Become. The heat storage body of the present invention is stable because a metal is contained in the dispersion, and can be effectively used for a heat storage system that repeats solidification / melting. Moreover, it has been found that a heat storage device or a heat storage system using such a heat storage body can be suitably used for the purpose of labor saving and efficiency improvement of air conditioning energy, environmental protection, etc. The present inventors have arrived at the present invention.

That is, the present invention is a heat storage body that essentially includes an oily substance having heat storage properties due to phase change, an aqueous medium, and a dispersant, and the heat storage body includes a heat storage material containing a metal element in the third period and / or the fourth period. Is the body.
The present invention is also a heat storage device or a heat storage system using the heat storage body.
The present invention is described in detail below.

The heat storage body of the present invention essentially comprises an oily substance, an aqueous medium and a dispersant, and the heat storage body contains a metal element of the third period and / or the fourth period. That is, as a constituent component contained in the heat storage body, a specific metal element is essential in addition to the oily substance, the aqueous medium, and the dispersant. This prevents water and oil-based heat storage materials from being separated by repetition of solidification / melting due to the phase change of the heat storage body, and includes the metal element of the third period and / or the fourth period. Stability is improved and a heat storage body useful for a heat storage system or the like can be provided by a simple method.

The metal element of the third period and / or the fourth period is a metal element included in the third period and / or the fourth period in the long-period periodic table, and the third period or the fourth period The metal elements are Na, Mg, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, and Ge. Among these, metals of Group 8, 1B, 2B, 3B are preferable, and Al, Fe, Cu, and Zn are more preferable. The heat storage body of the present invention may contain one or more of these metal elements.

In the heat storage body of the present invention, the metal element may be added to the heat storage body in advance, and when the heat storage body is used in a heat storage device or a heat storage system having a metal pipe, the metal is eluted from the pipe to store heat. It may be gradually added to the body. Moreover, the heat storage body to which a metal element has been added in advance may be used in a heat storage device or a heat storage system having a metal pipe, that is, used under metal contact. The heat storage system is equipped with a heat storage device in which the heat storage body is stored, a heat exchanger, and a pipe for circulating between the heat exchangers, and metal is eluted from the pipe and gradually added to the heat storage body Is composed of metal parts such as iron, copper, stainless steel, zinc, aluminum, etc., and the heat storage body contains metal by using it in contact with the metal. The form is preferred. When the metal element is added in advance, the metal element may be added in the form of a compound such as an oxide, or may be added in a solution state, that is, in the form of ions.
It is preferable that content of the metal element contained in the said heat storage body is 1 ppm or more and 5000 ppm or less. More preferably, they are 50 ppm or more and 1000 ppm or less, More preferably, they are 100 ppm or more and 500 ppm or less.

In addition, when a heat storage body that requires an oily substance having heat storage properties, an aqueous medium and a dispersant due to the phase change of the present invention is used in the heat storage system, the heat storage system is in contact with metal parts used in the heat storage system. After subjecting the oily substance of the body to solidification / melting phase change, when the content of the oily substance in the dispersion is 50% by mass, the viscosity of the dispersion is 5 to 2000 mPa · s at a temperature of 4 ° C. It is preferable that it is s. Thereby, the dispersibility of the oily substance is enhanced, the fluidity is improved, and the heat transfer performance can be further improved.

The oily substance essential for the heat storage body of the present invention has heat storage properties due to phase change. That is, it has latent heat storage using latent heat at the time of phase change or phase transition as a heat storage property, has a high heat storage density, and can store and dissipate heat at a constant temperature. Thereby, for example, it becomes possible to store and release thermal energy such as sensible heat storage, latent heat storage, and chemical reaction heat storage.

Examples of components constituting the oily substance, hydrocarbon compounds such as paraffin or α- olefins; higher fatty acids; higher fatty acid esters; a suitable compound such as higher alcohols, specifically, C ₁₄ paraffins, C ₁₅ paraffins, intermediate paraffin which is liquid at normal temperature C ₁₆ paraffin; C ₁₇ paraffins, C ₁₈ paraffins, C ₁₉ paraffins, C ₂₀ paraffins, C ₂₁ paraffins, C ₂₂ paraffins, C ₂₃ paraffins, C ₂₄ paraffins, C Higher paraffins that are solid around room temperature such as ₂₅ paraffin; higher alcohols such as 1-decanol are preferred. Among these, since it is convenient to handle, in the case of a heat storage body for building air conditioning, an oil-based one that is liquid at room temperature (25 ° C.) and normal pressure (about 101.3 kPa) has heat storage properties due to phase change. It is preferable to use it as a component constituting the substance. In addition, paraffin is preferable because it can be easily obtained and a heat storage body that can be used in a wide temperature range can be easily and stably produced. It is preferable to contain.

As the oily substance, a single component may be used, but the melting point can be adjusted to the heat storage temperature to be used by arbitrarily adjusting the type and blending ratio of the oily substance having heat storage property by phase change. it can. When used as a cooling application, an oily substance having heat storage properties may be selected by a phase change having a melting point of about 5 to 20 ° C. Moreover, what is necessary is just to select the oil-based substance which has heat storage property by the phase change which has a melting point in about 40-60 degreeC, when using it for a heating use.

The oily substance constituting the heat storage body of the present invention is (1) composed of three or more components, and the dispersion of the mass fraction of each component is 0.3 or more and 0.5 or less, or (2) 2 It is preferably composed of components or more, and the dispersion of the mass fraction of each component is 0.9 or more and less than 1.0. In the case of (1), the dispersion of the mass fraction of each component is preferably 0.35 or more and 0.45 or less, and in the case of (2), preferably 0.920 or more. Moreover, it is 0.998 or less.

The dispersion (V) of the mass fraction of each of the above components is a value determined by the following formula.

In the formula, n represents the number of components constituting the oily substance. x represents the mass fraction of each component when the total mass of the oily substance is 1.
When the dispersion (V) obtained by the above formula is 0, it means that all components constituting the oily substance are the same amount, and when the dispersion (V) is 1.0, the oily substance is constituted. It means that the component is a single component (one component constitutes 100% of the oily substance).
Note that the function (VAR) for calculating the variance for the population, assuming that the argument is a sample of the population, calculates the variance using the following equation.

In the formula, n and x are the same as described above.
In the present invention, when there is no dispersion regardless of the number of components constituting the oily substance (when one component constitutes 100% of the oily substance), 1.0 is the maximum dispersion (all of which constitute the oily substance) In this case, the number of components is multiplied by the formula for the VAR function so as to be 0 to 1.0. Therefore, the calculation formula of the dispersion (V) of the mass fraction of each component is an expression obtained by multiplying the calculation formula of the VAR function by the number of components n.

In the form of (1), three or more of the components constituting the oily substance are used, and in the form of (2), two or more of these components are used in combination. In the present invention, one compound constitutes one component. For example, when paraffins having the same carbon number and isomers such as linear paraffin and branched paraffin are included, each of them is regarded as one component. To do.

The oily substance in the form (1) is inexpensive and easily available, and it is easy to adjust the phase change temperature. Therefore, the oily substance is preferably a three-component or more homologue of a hydrocarbon compound. For example, in the case of cold _{applications, C 14 paraffins,} mixtures of _{C 15} paraffin and _{C 16} paraffins or paraffin carbon _{number; C 14 paraffins,} mixtures of _{C 16} paraffin and _{C 18} paraffins are preferred. Moreover, as these mass _{fraction, C 14 paraffins,} in a mixture of _{C 15} paraffin and _{C 16} paraffins or paraffin carbon _{number, C 14 paraffins: C 15 paraffins: C 16} paraffin or more carbon atoms paraffin = 0 .2～30: 50-80: 2-20 is _suitable, in _{C 14 paraffins,} mixtures of _{C 16} paraffin and _{C 18 paraffins, C 14 paraffins: C 16 paraffins: C 18} paraffins = 0.2 to 40: 50-60: 2-10 are suitable, and the oily substance comprised from such a component is one of the preferable embodiments in the present invention.

The oily substance in the above form (2) is preferably one containing as a main component at least one hydrocarbon compound selected from the group consisting of 14, 15, 17 and 19 carbon atoms. More preferably, the main component is a hydrocarbon compound having 14 and / or 15 carbon atoms. The hydrocarbon compound is preferably paraffin. The “main component” means a component that constitutes 50% by mass or more, assuming that all components constituting the oily substance are 100% by mass, and the main component is composed of one component. It may also be constituted by two or more components. When the main component is composed of two or more components, the total of the components constituting the main component may be 50% by mass or more.

The amount of the oily substance used may be appropriately set according to the type of oily substance having heat storage properties due to phase change, the usage form of the heat storage body, and the required heat storage efficiency, but 10 mass% in 100 mass% of the heat storage body. % Or more, and preferably less than 100% by mass. If it is less than 10% by mass, the heat storage efficiency and the heat storage performance may be reduced. More preferably, it is 20 mass% or more, and is 75 mass% or less.

It is preferable to add a crystal nucleating agent to the oily substance. The crystal nucleating agent may be any substance that can become a crystal nucleus when solidifying the heat storage body, but is preferably a substance having a crystal structure similar to that of an oily substance having heat storage properties due to phase change. It is preferable that the substance has a melting point higher than that of the substance and that solidifies from an early stage. Furthermore, a substance having a phase change temperature higher by 10 to 100 ° C. than the melting point of the oily substance is more preferable. Even if the melting point of the crystal nucleating agent is less than 10 ° C. or more than 100 ° C. than the melting point of the oily substance, the function as the crystal nucleating agent is reduced and the solidification / melting temperature divergence (supercooling phenomenon) is sufficient. Cannot be prevented.

As the above-mentioned crystal nucleating agent, when normal pentadecane is used as an oily substance having heat storage property by phase change, normal heptadecane, normal octadecane, normal nonadecane, normal eicosane, normal docosane, normal tricosane, normal Saturated hydrocarbons such as tetracosane and normal pentacosane, unsaturated hydrocarbons such as 1-octadecene, higher fatty acids such as stearic acid, higher alcohols such as octadecanol, sorbitan fatty acid esters such as sorbitan tristearate, polyoxyethylene Polyoxyethylene sorbitan esters such as sorbitan tristearate, sucrose fatty acid esters such as sucrose stearate, glycerin fatty acid esters such as tristearin, fatty acid amides such as stearamide, etc. . Of these, sucrose fatty acid esters and saturated hydrocarbons are preferred. These crystal nucleating agents may be used in combination of two or more if necessary.

The amount of the crystal nucleating agent added is preferably 0.5% by mass or more and preferably 20% by mass or less with respect to 100% by mass of the oily substance. If it is less than 0.5% by mass, it is not possible to sufficiently prevent supercooling. If it exceeds 20% by mass, the content of the oily substance having heat storage in the heat storage body is reduced, so that the heat storage efficiency is sufficient. It cannot be improved. More preferably, it is 1% by mass or more and 10% by mass or less.

In the heat storage body of the present invention, the aqueous medium contains water as an essential component, but a mixture of water and a solvent that dissolves in water can be used. For example, water and methanol, ethanol, isopropyl alcohol, acetone A mixed solvent with acetonitrile, ethylene glycol, diethylene glycol or the like is preferable. The proportion of water in the aqueous medium is preferably 50% by mass or more, more preferably 80% by mass or more. More preferably, only water is used.
The amount of the aqueous medium used is preferably 5.0% by mass or more and preferably 900% by mass or less with respect to 100% by mass of the oily substance having heat storage properties due to phase change.

The dispersant in the present invention preferably has a structure having an ethylene oxide addition mole number of 5 or more, and includes a nonionic surfactant, an anionic surfactant, a cationic surfactant, and a nonionic-anionic interface. Activators, amphoteric surfactants, and polymer dispersants can be mentioned. These dispersants may be used alone or in combination of two or more. Among these, it is preferable that a nonionic surfactant is essential. When the emulsion dispersant contains a nonionic surfactant as an essential component, an aqueous dispersant solution is formed by the aqueous medium and the dispersant constituting the heat storage body, but the cloud point of the dispersant is preferably higher than the heat storage temperature. The cloud point means a temperature at which a transparent aqueous solution starts to become cloudy when the temperature of the aqueous solution of the nonionic surfactant is increased. When using a nonionic surfactant as an emulsifier, it is important that the heat storage temperature range is below the cloud point. As a result, in the heat storage temperature range in which the heat storage body is used, the dispersion of the dispersant is suppressed and the stability of the emulsion is suppressed, and the fluidity of the heat storage body is improved and the heat transfer performance of the heat storage body is improved. Or the load on the circulation pump that feeds the heat storage body can be further reduced. In this case, it is preferable that the cloud point of the aqueous dispersant solution is higher by 5 ° C. or more than the heat storage temperature. More preferably, it is 10 degreeC or more.

Examples of the nonionic surfactant include sorbitan ester compounds such as polyoxyalkylene sorbitan alkyl ester and sorbitan alkyl ester; sucrose fatty acid ester; polyoxyethylene alkyl ether; polyoxyethylene alkylphenol ether; polyoxyethylene alkyl ester; Suitable are glycerin alkyl esters; fatty acid esters; fatty acid soaps; alkylamine ethylene oxide adducts; and sterols such as cholesterol. These may be used alone or in combination of two or more.

Among these, what has a structure whose ethylene oxide addition mole number is 5 or more is preferable. Among those having such a structure, the number of added moles of ethylene oxide is 5 or more, preferably 100 or less, more preferably 50 or less. The total carbon number is 15 or more, preferably 40 or less, more preferably 30 or less.
Of these, polyoxyethylene stearyl ether, polyoxyethylene behenyl ether, and polyoxyethylene sorbitan stearate having an ethylene oxide addition mole number of 20 or more are more preferable.

As the dispersant, amphoteric surfactants, anionic surfactants, nonionic-anionic surfactants and cationic surfactants may be used as appropriate. As these surfactants, alkyl sulfate salts such as sodium alkyl sulfonate; alkyl benzene sulfonic acids and salts thereof such as sodium alkyl benzene sulfonate; alkyl (phenyl) ether sulfate salts such as sodium polyoxyethylene lauryl ether sulfate; tetradecene Preferred are α-olefin sulfonates such as sodium sulfonate; sulfosuccinates; ether sulfonates; ether carboxylic acids and salts thereof; betaines such as amidopropyl betaine laurate; and quaternary ammoniums such as dialkylammonium chloride.

As the dispersant, a polymer dispersant described later is preferably used in combination with the surfactant.
These dispersants can be appropriately used as long as the volume average particle size variation of the dispersion described above does not deviate from the above-defined preferred range when mixed.
In the present invention, the dispersant is composed of a surfactant, and the surfactant has a hydrophilic / lipophilic balance index of less than 12 and a hydrophilic / lipophilic balance index of 12 or more. Is essential. More preferably, it is essential to have less than 9 and 12 or more. More preferably, it is essential to have less than 3 and 12 or more. In this case, due to the synergistic effect by combining the low and high hydrophilic lipophilic balance index, supercooling is more effectively prevented than when a single surfactant is used, It becomes easier to solidify and heat storage efficiency is improved.

The hydrophilic / lipophilic balance index represents the balance between the hydrophilic part and the lipophilic part of the surfactant, and is usually referred to as HLB (hydrophile-lipophile balance). A surfactant having a larger numerical value of this index has higher hydrophilicity.
The HLB of a surfactant with a clear molecular structure can be determined by the calculation formulas of Griffin and Davies. In addition, even for a surfactant whose molecular structure is not clear, the HLB can be experimentally determined by conducting an emulsification experiment using an oily substance and a surfactant having a known HLB.

The surfactant in the present invention contains at least one surfactant having a hydrophilic / lipophilic balance index of less than 12 and at least one surfactant having a hydrophilic / lipophilic balance index of 12 or more. Thus, it is preferable that the hydrophilic / lipophilic balance index of the whole surfactant obtained from the mass fraction of each surfactant constituting the surfactant in the present invention is 5 or more and 15 or less. If it is less than 5, the stability of the emulsion may be lowered, and if it exceeds 15, overcooling may not be prevented. More preferably, it is 5 or more, and is 12 or less, More preferably, it is 11 or less.

As an index of the hydrophilic / lipophilic balance of the whole surfactant, the following formula:
Σ (Xi × HXi) + Σ (Yj × HYj): i is obtained from 1 to ni, and j is obtained from 1 to nj. In this formula, the index of the hydrophilic / lipophilic balance of the entire surfactant is obtained from the sum of the values obtained by multiplying the mass fraction of each surfactant constituting the surfactant by the index of the hydrophilic / lipophilic balance. It will be.

In the above formula, Xi is the mass fraction of the surfactant i having a hydrophilic / lipophilic balance index of less than 12 when the mass of the entire surfactant is 1, and Yj is the mass of the entire surfactant. Is the mass fraction of surfactant j having a hydrophilic / lipophilic balance index of 12 or more, where HXi is the hydrophilic / lipophilic balance of surfactant i having a hydrophilic / lipophilic balance index of less than 12. HYj is an index of hydrophilic / lipophilic balance of surfactant j having a hydrophilic / lipophilic balance index of 12 or more. In the above formula, i and j are numbers assigned to the surfactant used in the present invention, and the numbers differ depending on the type of the surfactant. In addition, i = 1, 2, 3,... N ₁ , j = ₁ , ₂ , 3,... N ₂ , and n ₁ represents the total number of types of surfactants having a hydrophilic / lipophilic balance index of less than 12. n ₂ is the index of the hydrophile-lipophile balance represents the total number of types of 12 or more surfactants.

As described above, a nonionic surfactant is preferably used as the surfactant used in the heat storage body of the present invention. Among the above nonionic surfactants, those having an HLB of less than 12 are sorbitan. Alkyl esters and / or sucrose fatty acid esters are preferred. Moreover, as 12 or more, polyoxyalkylene sorbitan alkyl ester and / or polyoxyethylene alkyl ether are preferable. Among these, polyoxyethylene (ethylene oxide addition mole number 20 or more) sorbitan alkyl (total carbon number 15 or more) ester and / or polyoxyethylene (ethylene oxide addition mole number 20 or more) alkyl (total carbon number 15 or more) ether. More preferred.

The amount of the surfactant used is appropriately set so that the volume average particle size change amount as described above can be within a preferable range, but with respect to 100% by mass of the oily substance, It is preferable to set it as 0.1 mass% or more, and it is preferable to set it as 30 mass% or less. More preferably, it is 1.0 mass% or more, and is 20 mass% or less.

The amount of the surfactant having a hydrophilic / lipophilic balance index of less than 12 is preferably 5.0% by mass or more and 95% by mass or less with respect to 100% by mass of the surfactant. It is preferable. More preferably, it is 10 mass% or more and 50 mass% or less. The amount of the surfactant having a hydrophilic / lipophilic balance index of 12 or more is preferably 5.0% by mass or more and 95% by mass or less with respect to 100% by mass of the surfactant. It is preferable. More preferably, it is 50 mass% or more and 90 mass% or less.

The heat storage body of the present invention preferably comprises a dispersion obtained by dispersing an oily substance having heat storage properties by a phase change in a water-based medium by using a polymer dispersant together with a surfactant. Thus, by using a surfactant and a polymer dispersant in combination as a dispersant, it is possible to sufficiently improve the stability of the emulsion due to a synergistic effect thereof.
In addition, in this invention, 1 type may be used for these manufacturing raw materials which comprise a thermal storage body, respectively, and 2 or more types may be used together.

The polymer dispersant in the present invention is not particularly limited as long as it is a high-molecular substance that easily gets wet or dissolves in water. For example, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, polyvinyl methyl ether, polyethylene oxide, polypropylene oxide, (meth) acrylic acid ester copolymer, (meth) acrylic acid (meth) acrylic acid ester copolymer, methylcellulose, methylhydroxy Propylcellulose, hydroxypropylmethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, soluble starch, dextrin, gum arabic, chitosan, agar, gelatin, soy casein, polyacrylic acid, sodium polyacrylate, acrylic acid acrylate copolymer, acrylic Sodium acid sodium maleate copolymer, polymaleic acid, polyvinyl sulfonic acid, polystyrene sulfonic acid sodium Beam, sodium carboxymethyl cellulose, polyethyleneimine, polydiallylamine, polyallylamine, poly N- vinylformamide, polyvinylamine, polyamidine the like. In the polymer dispersant which is easily dissolved in water, when dissolved in water at 25 ° C., it is preferable that 80% by mass or more is dissolved.
Among these, as the nonionic polymer dispersant, those having a weight average molecular weight of 5,000 to 300,000 are preferable, more preferably 50,000 to 200,000, and a nonionic polymer having such a weight average molecular weight. As the polymer dispersant, polyvinyl alcohol, polyvinyl pyrrolidone, hydroxypropylmethyl cellulose and the like are preferable. The ionic polymer dispersant preferably has a weight average molecular weight of 5,000 to 3,000,000, preferably 50,000 to 3,000,000, and more preferably 100,000 to 2,000,000. As the ionic polymer dispersant having the above, sodium polyacrylate or the like is preferable.

The amount of the polymer dispersant used is preferably 0.001% by mass or more and more preferably 5% by mass or less with respect to 100% by mass of the oily substance having heat storage properties due to phase change. More preferably, it is 0.01% by mass or more and 3% by mass or less.

In the present invention, when a nonionic surfactant is used as an essential component as a dispersant, a nonionic surfactant may be used alone, but as described above, a nonionic surfactant and another dispersant may be used. You may use together. Specific examples of combined use include a combination of a nonionic surfactant and an anionic surfactant, a combination of a nonionic surfactant and a cationic surfactant, and a combination of a nonionic surfactant and a nonionic-anionic surfactant. Combination, Nonionic surfactant and amphoteric surfactant, Nonionic surfactant and polymer dispersant, Nonionic surfactant, anionic surfactant and polymer dispersant, Nonionic surfactant And a combination of a cationic surfactant and a polymer dispersant.

The heat storage body of the present invention may further contain an additive having the functions described below. These may be used alone or in combination of two or more.
(1) For heat transfer improvement: metal powder; metal fiber; metal oxide; carbon;
(2) Specific gravity adjustment: sand; clay; stone; metal powder such as lead.

(3) For imparting flame retardancy: water; water gel; metal powder; inorganic compounds such as calcium carbonate; brominated, chlorinated, phosphorous and other flame retardants. In addition, the flame retardancy includes reduction of combustibility, prevention of fire spread, extinction of flash point by water vapor, reduction of combustion heat, and the like.
(4) For supercooling prevention: metal powder, polymer paraffin (wax), etc.
(5) For freezing point adjustment: waxes and the like.
(6) Antioxidation and prevention of deterioration over time: Antioxidants such as phenol, thio, and phosphorus.
(7) Other: Coloring agent, pigment, antistatic agent, antibacterial agent and the like.
In addition, in said (1)-(4), when using a metal powder, a metal transition, a metal oxide, etc., the metal element of a 3rd period or a 4th period may be contained by these in a heat storage body. .

The amount of the additive used is, for example, preferably 10 to 40% by mass with respect to the oily substance having heat storage properties due to phase change when calcium carbonate is used in order to reduce combustibility. .

An inclusion compound for adjusting the latent heat property may be added to the oily substance.
Examples of the inclusion compound include C ₄ H ₈ · O · 17H ₂ O, (CH ₃ ) ₃ N · 10.25H ₂ O, (C ₄ H ₉ ) ₄ NCHO ₂ · 32H ₂ O, and (C ₄ H _{9 4} NCH ₃ CO ₂ .32H ₂ O is preferred. These may be used alone or in combination of two or more.

As the heat storage body of the present invention, 50 times of repetition of solidification / melting due to phase change is performed, and the volume average particle diameter change of the dispersion is smaller than the volume average particle diameter before the repetition of solidification / melting. The preferred form is within ± 50%. By setting it as such a form, it can be set as the thermal storage body which can be used suitably for the objectives, such as labor saving and efficiency improvement of air-conditioning energy, and environmental protection.
The repetition of the above solidification / melting means that the operation of storing heat as latent heat in an oily substance having heat storage properties by phase change and releasing the stored heat is performed.

In the repetition of solidification / melting due to the phase change of the oily substance having the heat storage property, it is more preferable that the volume average particle size change is within the above range at 100 times or more, more preferably 200 times or more. . In the repetition of solidification / melting of the oily substance, the smaller the change in the volume average particle diameter of the dispersion, the less the destruction of the oily substance in the dispersion, and the longer the stable use.

As a repeated test of solidification / melting due to the phase change of the oily substance, it is preferable to put a heat storage body in a sample bottle and perform a cycle test at a temperature at which the solidification / melting can be repeated due to phase change. For example, when pentadecane having a melting point of 10 ° C. is used as the oily substance, it can be carried out by adjusting the heat storage body to 5 to 7 ° C. when solidifying by phase change. Next, when melting, it can be carried out by adjusting the heat storage body at 12 to 15 ° C.

The amount of change (%) in the volume average particle diameter is calculated as follows.
Volume average particle diameter change (%) = (volume average particle diameter after 50 solidification / melting repetitions−volume average particle diameter before solidification / melting repetition) ÷ (volume average particle before solidification / melting repetition) Diameter) x 100
The volume average particle diameter is measured using a laser diffraction particle size distribution analyzer SALD-3000 manufactured by Shimadzu Corporation. Moreover, ion-exchange water is used as a measurement medium.

The heat storage body of the present invention preferably has a form in which the dispersant concentration at a heat storage temperature of an aqueous dispersant solution composed of an aqueous medium and a dispersant is 0.01 to 4 times the saturation temperature of the dispersant.
The heat storage body of the present invention in such a preferred form is obtained by dispersing an oily substance having heat storage properties by phase change in an aqueous medium with a dispersant, and the amount of the dispersant used is specified.

In the present invention, in order to specify the amount of the dispersant used, when the aqueous dispersant solution is formed from the aqueous medium constituting the heat storage body and the dispersant, the dispersant concentration of the saturated solution at the heat storage temperature of the aqueous dispersant solution Based on the above, the dispersant concentration is calculated. For example, when a dispersant having a saturation concentration of 30% by mass at a heat storage temperature is used, the dispersant concentration is 0. 0% with respect to the saturation concentration. It becomes 1 time.
Thus, when based on the dispersant concentration of the saturated solution at the heat storage temperature of the dispersant aqueous solution, the dispersant concentration of the dispersant aqueous solution at the heat storage temperature is 0.01 to 4 times, The amount of dispersant used will be set.
The saturated solution means a solution in which the maximum amount of the dispersant that can be dissolved in an aqueous medium is dissolved, and the saturated concentration means the content of the dispersant in the aqueous dispersant solution, which is a saturated solution, in mass%. It is a thing. In the present invention, when the dispersant is dissolved in an aqueous medium, the saturated solution includes a solution in which the maximum amount that does not cause gelation (when fluidity is lost) is reached before saturation is reached.

The said heat storage temperature means the temperature range of the heat storage body from the temperature used in order to store heat to the oily substance which has heat storage property by a phase change to the temperature used in order to discharge | release heat. In the heat storage body of the present invention, the dispersant concentration is used in a range of 0.01 to 4 times the saturation concentration of the dispersant over the entire temperature range of the heat storage body to be used.
If the dispersant concentration is less than 0.01 times the saturation concentration, the oily substance having heat storage properties cannot be sufficiently dispersed due to the phase change, and if it exceeds 4 times, the dispersant precipitates and oil drops There is a risk that the stability of the emulsion may be reduced due to the loss of formation.

The preferred form of the present invention is 0.01 to 1 times the saturation concentration. As a result, the fluidity in the heat storage temperature range is lowered, the heat transfer performance is lowered, and the load of the circulation pump that feeds the emulsion is suppressed from increasing. It becomes possible to demonstrate to. More preferably, it is 0.05 times or more and 1 time or less with respect to the saturated concentration. More preferably, it is 0.1 times or more and 0.5 times or less.
When using a dispersant that has solubility in an aqueous medium, if the dispersant is added in excess of the saturation concentration to produce an emulsion, the fluidity in the heat storage temperature range decreases, so heat transfer Inconveniences such as a decrease in performance and an increase in the load of the circulation pump for feeding the emulsion occur. Also, at the time of emulsion preparation, if the saturation concentration significantly exceeds the saturation temperature range even below the saturation concentration, when the dispersant forming the oil droplets comes off and moves to the water side, it precipitates and forms oil droplets. It will not be involved and will reduce the stability of the emulsion. When the heat storage body of the present invention is used by dissolving the dispersant in a predetermined concentration range, the above-mentioned problems can be solved and a durable emulsion can be obtained.

The heat storage body of the present invention comprises an oil-in-water dispersion for heat storage containing the oily substance having heat storage properties due to the phase change, the aqueous medium, and the dispersant, and the oily substance in the dispersion. When the content of is 50% by mass, the dispersion preferably has a viscosity of 5 to 2000 mPa · s at a temperature of 4 ° C.
In the present invention, the dispersion having a viscosity of 5 to 2000 mPa · s at a temperature of 4 ° C. when the content of the oily substance in the dispersion is 50% by mass is a preferred form, but a more preferred form. As for, the viscosity of a dispersion is 5-1000 mPa * s, More preferably, a viscosity is 5-500 mPa * s. When the viscosity exceeds 2000 mPa · s, the fluidity is lowered, and a load may be generated on the pump for feeding the heat storage body. Moreover, there exists a possibility that heat conductivity may fall because a viscosity becomes high. Moreover, when making a viscosity less than 5 mPa * s, it is necessary to adjust content of the oil-based substance contained in a dispersion to less than 50 mass%. When the amount of the oily substance is reduced, the heat storage amount is lowered, and the performance as the heat storage body is lowered. This also becomes an unfavorable form as the heat storage body.
The viscosity in the present invention is measured at 4 ° C. using a B8L type (manufactured by Tokimec) viscometer.

The heat storage body of the present invention comprises an oil-in-water dispersion for heat storage that essentially comprises an oily substance having heat storage properties due to the phase change, the aqueous medium, and the dispersant, and has heat storage properties due to the phase change. In an oil-in-water dispersion for heat storage that essentially includes an oily substance, an aqueous medium, and a dispersant, the oily substance of the dispersion is subjected to solidification / melting phase change, and then the content of the oily substance in the dispersion is 50% by mass The dispersion preferably has a viscosity of 5 to 2000 mPa · s at a temperature of 4 ° C. Even when the solidification / melting phase change is performed on the oily substance, when the viscosity is 5 to 2000 mPa · s, the dispersibility of the oily substance is improved, the fluidity is improved, and the heat transfer performance can be improved. .

The heat storage body of the present invention according to the above form is an oil-in-water dispersion for heat storage that essentially comprises an oily substance having heat storage properties by phase change, an aqueous medium and a dispersant, and performs solidification / melting phase change on the oily substance. The viscosity after performing is specified. Solidification / melting phase change refers to storing heat as latent heat in an oily substance having heat storage properties by the phase change and dissipating the stored heat. In the present invention, solidification / melting is performed only once. This includes the case where it is performed.

The phase change of the solidification / melting of the oily substance can be carried out using a method similar to the method described for the repeated test of solidification / melting. Moreover, it can carry out also in the heat storage water tank which stores the thermal storage body with which the thermal storage apparatus or the thermal storage system is equipped, the piping which sends a thermal storage body, a heat exchanger, etc.
In addition, the phase change of solidification / melting of the oily substance may be repeated. The number of repetitions of the phase change due to solidification / melting of the oily substance having heat storage property is preferably 50 times or more, more preferably 100 times or more. In the repeated phase change of the oily substance, the smaller the change in viscosity due to deterioration of the heat storage body, the more stable it can be used in the long term.

Examples of the method of dispersing the oily substance in the aqueous medium in the heat storage body of the present invention include a method of encapsulating the oily substance in microcapsules and a method of forming an oil-in-water emulsion with a dispersant.

In the above dispersion method, the method of encapsulating the oily substance in the microcapsule includes an encapsulation method by a composite emulsion method, a method of spraying a thermoplastic resin on the surface of the heat storage material particles, and a thermoplastic in liquid on the surface of the heat storage material particles. A method such as a method of forming a resin, a method of polymerizing and coating a monomer on the surface of the heat storage material particles, and a method of producing a polyamide-coated microcapsule by an interfacial polycondensation reaction are suitable. As a method of making an oil-in-water emulsion with a dispersant, a method of making an oil-in-water emulsion with a dispersant containing a nonionic surfactant essential for the dispersant in the present invention is suitable.
As a method of dispersing the oily substance in the aqueous medium in the present invention, among the above two methods, a method of forming an oil-in-water emulsion with a dispersant is preferable.

As the heat storage body of the present invention, for example, a method of adding an oily substance having heat storage properties by phase change to an aqueous solution in which a dispersant is dissolved in an aqueous medium, and emulsifying by stirring or the like, or a polymer dispersant in an aqueous medium It is preferable to produce the solution by adding an oily substance having heat storage properties by a phase change in which the surfactant is dissolved in the aqueous solution dissolved in the emulsion, and emulsifying by stirring or the like. Such a manufacturing method is one of the preferred embodiments of the present invention.

The heat storage body of the present invention also includes a crystal nucleating agent, an oily substance having heat storage properties due to phase change, an aqueous medium, and a heat storage body obtained by dispersing a mixture essentially containing a dispersant in an oil-in-water type. It is preferable to manufacture by a method of dispersing again after changing, and such a manufacturing method is also one of the preferred embodiments of the present invention.

The method for producing a heat storage body of the present invention is a method for producing a heat storage body by dispersing an oily substance having heat storage properties by a phase change, an aqueous medium and a mixture essential to a dispersant in an oil-in-water type, The manufacturing method of the said heat storage body comprises the process of disperse | distributing the oil-based substance which has heat storage property by a phase change by using a line mixer.

In the method for producing a heat storage body of the present invention, a heat storage obtained by dispersing a crystal nucleating agent, an oily substance having heat storage properties due to phase change, an aqueous medium, and a production raw material essential for a dispersant into an oil-in-water type. After the solid body is repeatedly solidified / melted by phase change by using it in a heat storage device or the like, the heat storage body is dispersed again. Is a state in which the oily substance is sufficiently dispersed by stirring the heat storage body in a dispersed state to maintain the dispersion state of the oily substance, or by redispersing the heat storage body from which the oily substance is separated. The production method of the present invention is applied to any of these or a combination thereof.

In the method for producing a heat storage body of the present invention, (1) a form for producing a dispersion of an oily substance from production raw materials, (2) a form for maintaining a dispersion state in the dispersion of the oily substance, (3) dispersion of the oily substance In the case where the body disintegrates and separates into an oil layer and an aqueous layer, the dispersible dispersion may be redispersed, and applied to any of these or a combination thereof.

In this invention, said form is implemented in the process of disperse | distributing the oil-based substance which has heat storage property by a phase change using a line mixer. That is, in the step of dispersing the oily substance, not only the process of obtaining a dispersion of the oily substance by stirring from the production raw material using a line mixer, but also the heat storage body in which the oily substance is already dispersed is lined up. It also includes a step of maintaining the dispersed state of the oily substance by stirring with a mixer, or a state in which the oily substance is sufficiently dispersed by redispersing the heat storage body from which the oily substance is separated. The heat storage body in which the oily substance is already sufficiently dispersed or the heat storage body from which the oily substance is separated may be a heat storage body obtained by the production method of the present invention, or obtained by a production method other than the present invention. A heat storage body may be used. In any of these forms, the heat storage body is normally stored in the tank.

The line mixer in the present invention does not directly stir the manufacturing raw materials in the tank, but disperses them by baffle plates, protrusions, and mechanical stirring installed in the middle of the piping through which the manufacturing raw materials in the tank pass. Means a distributed device.
Examples of the line mixer include a type having a stirring drive unit such as a motor that can disperse an oily substance having heat storage properties by phase change in the mixer itself, and a type having no stirring drive unit in the mixer itself. In addition, when using the mixer which does not have a stirring drive part, the circulation pump for sending a manufacturing raw material etc. is needed.

As the type of line mixer having the agitation driving unit, one having not only a mixer but also a pump capability is suitable. In this case, there is no need to install a pump in the piping, which is preferable in terms of simplifying the manufacturing equipment. However, if the capacity as a pump is insufficient, an additional pump may be installed. As such a line mixer, an in-line mixer 450LS type (manufactured by Silverson) having a rotor that rotates at high speed, T.C. K. Pipeline homomixer PL-2S type (made by Tokushu Kika Kogyo Co., Ltd.) and the like can be mentioned. Such a line mixer, for example, stirs and disperses production raw materials and the like by a strong suction force, centrifugal force, and shearing force due to the rotor rotating at high speed.

As the type of line mixer that does not have the agitation drive unit, an agitator that utilizes the flow of fluid generated by a pump or the like is suitable. As such a line mixer, an OHR (Original Hydrodynamic Reaction) line mixer MX-8 type (manufactured by Seika Sangyo Co., Ltd.), a static mixer (manufactured by Noritake Company Limited), and Mr. Disperse (manufactured by Fujikin Co., Ltd.) , Line mixer SMX type, SMV type (manufactured by Coke Gridge Inc.) and the like. Such a line mixer has, for example, an element obtained by twisting a rectangular plate by 180 ° or a mushroom-like collision body in the line mixer, and the production raw materials and the like are obtained by the action of these elements and the collision body. Stir and disperse.

The production form in the present invention may be any form that will be stirred using a line mixer. For example, a pipe is connected to a tank into which production raw materials and the like are charged, and a line mixer is installed in the middle of the pipe. The form is preferred. In the installation of the line mixer, the number and position of installation may be set as appropriate depending on the production scale, the characteristics of the production raw material, the speed of the production raw material passing through the piping, the flow rate per unit time, etc. A line mixer is preferably installed. Moreover, as a form which supplies manufacturing raw materials etc. to a line mixer, the mixture and dispersion in a tank may be supplied to a line mixer by piping, and piping which supplies each manufacturing raw material is connected to a line mixer. Production raw materials may be supplied by the above.

In the production mode of the present invention, when the line mixer is installed in the middle of the pipe, it may be dispersed by passing the mixture or dispersion only once through the pipe in which the line mixer is installed, and the line mixer may be passed twice or more. May be dispersed. Moreover, you may disperse | distribute the mixture and dispersion in a tank by circulating using the piping in which the line mixer was installed.

In the present invention, it is preferable to circulate the mixture or dispersion in the tank using a pipe in which a line mixer is installed, thereby producing a dispersion of an oily substance and maintaining or disintegrating the dispersion in the dispersion. In any form such as redispersion of the dispersion, the step of dispersing the oily substance can be performed easily and inexpensively.

The production form in the present invention may be any form that will be stirred using a line mixer. For example, a pipe is connected to a tank into which production raw materials and the like are charged, and a line mixer is installed in the middle of the pipe. The form is preferred. In the installation of the line mixer, the number and position of installation may be set as appropriate depending on the production scale, characteristics of the heat storage body, the speed of the heat storage body passing through the piping, the flow rate per unit time, etc. It is preferable to install a line mixer. Moreover, as a form which supplies a thermal storage body etc. to a line mixer, the thermal storage body etc. in a tank may be supplied to a line mixer by piping, and a thermal storage body etc. are supplied by connecting several piping to a line mixer. May be.

Hereinafter, the production mode of the present invention will be described in more detail with reference to the drawings.
FIG. 1 is a schematic diagram showing an embodiment using a manufacturing apparatus 1 in the manufacturing method of the present invention. The manufacturing apparatus 1 includes a tank 2 for supplying manufacturing raw materials and a heat storage body, a line mixer 3 having a pumping capacity to itself, pipes 4 and 5 connected via the line mixer 3, and obtained dispersion It is comprised by the extraction piping 6 of a body. The pipe 4 is connected to the bottom of the tank 2 and is connected to the line mixer 3. The pipe 5 is connected to the line mixer 3 and connected to the tank 2. When manufacturing a heat storage body from a manufacturing raw material with such a manufacturing apparatus 1, first, a manufacturing raw material is thrown into the tank 2, and is sent to the line mixer 3 through the piping 4 as a liquid mixture. This mixed liquid is dispersed by stirring in the line mixer 3 and returns to the tank 2 through the pipe 5 as a dispersion. The dispersion returned to the tank 2 is stirred by convection in the tank 2 and again sent to the line mixer 3 through the pipe 4. In such a production method, not only the dispersion is produced by introducing the heat storage body in which the oily substance is already dispersed into the tank 2 depending on the time for circulating the dispersion, etc. A distributed state can be maintained. Further, even when the oily substance is separated, the dispersion can be redispersed and maintained.

FIG. 2 is a schematic diagram showing an embodiment using the manufacturing apparatus 11 in the manufacturing method of the present invention. This production apparatus 11 includes a tank 12 for supplying a heat storage body, a line mixer 13 having a pumping capacity to itself, pipes 14 and 15 connected via the line mixer 13, and extraction of the obtained dispersion. It is comprised by the piping 16. The pipe 14 is connected to the bottom of the tank 12 and is connected to the line mixer 13. The pipe 15 is connected to the line mixer 13 and connected to the tank 12. In the case where the heat storage body is dispersed again by such a manufacturing apparatus 11, the phase of the heat storage body in the tank 12 is changed, and then the liquid is sent to the line mixer 13 through the pipe 14. This heat storage body is dispersed by stirring in the line mixer 13, and returns to the tank 12 through the pipe 15 as a dispersion. The dispersion returned to the tank 12 is again sent to the line mixer 13 through the pipe 14. In such a manufacturing method, the dispersion state of the dispersion can be maintained by charging the tank 12 with the heat storage body in which the oily substance is already dispersed. Further, even when the oily substance is separated, the dispersion can be redispersed and maintained.

In the production method of the present invention, other dispersing means other than the line mixer may be used if necessary, but the step of dispersing the oily substance having heat storage properties in the aqueous medium by the phase change is simply performed, and capital investment is made. From the viewpoint of suppressing the above, it is preferable to use only a line mixer as the dispersing means. When other dispersing means are used, a general machine can be used. For example, propeller stirrer, high-speed rotary stirrer, homomixer, high-pressure homogenizer, colloid mill, roll mill, roller mill, sand mill, ball mill, ultrasonic emulsifier, vacuum kneader, vacuum emulsifier, release emulsifier, etc. It is done.

In the production of the heat storage body, the same water tank used to obtain a heat storage body in which a mixture containing a crystal nucleating agent, an oily substance having heat storage properties due to phase change, an aqueous medium and a dispersant is dispersed in an oil-in-water form. Alternatively, the phase may be changed again in the dispersion tank and then dispersed again. In addition, after extracting the heat storage body from the water tank or dispersion tank used to obtain the heat storage body dispersed in the oil-in-water type, it is put into another water tank or dispersion tank used for the heat storage system and the phase change of the heat storage body Then, dispersion may be performed again. Further, after changing the phase of the heat storage body dispersed in the oil-in-water type, it may be dispersed again in the same water tank or dispersion tank, and after extracting the heat storage body from the water tank or dispersion tank, to another water tank or dispersion tank You may throw in and disperse again.

The present invention also provides a static mixer after changing the phase of a heat storage body obtained by dispersing a mixture containing an oily substance having heat storage properties, an aqueous medium and a dispersant in an oil-in-water type by phase change. It is also a manufacturing method of the heat storage body disperse | distributed again using.

The heat storage body obtained by dispersing the oily substance having heat storage properties due to the phase change, the aqueous medium and the mixture essential to the dispersant in an oil-in-water type is obtained by the production method of the present invention. Although it is preferable, there is no particular limitation. In the said manufacturing method, after changing a phase by using such a thermal storage body with a thermal storage apparatus etc., it will disperse | distribute again using a static mixer.

The present invention is also a method for producing a heat storage body comprising a dispersion obtained by dispersing an oily substance having heat storage properties by phase change in an aqueous medium in the presence of a dispersant, and the production of the heat storage body The method comprises a step of adjusting the amount of dispersant used based on the dispersant saturation concentration at the heat storage temperature of a dispersant aqueous solution obtained by mixing an aqueous medium and a dispersant. Is preferably a method for producing a heat storage body that is 0.01 to 4 times the saturation concentration of the aqueous dispersant solution. Such a manufacturing method is a preferable manufacturing method of the heat storage body of this invention.

In the above method for producing a heat storage body, as a method for making an oily substance having heat storage properties by phase change into an aqueous dispersion, for example, an oily material having heat storage properties by phase change is added to an aqueous solution in which a dispersant is dissolved in water. A method of adding and emulsifying by stirring or the like is preferable. In this case, the step of adjusting the concentration of the dispersant under the heat storage temperature of the aqueous dispersant is performed by specifying the amount of the dispersant used as described above when dissolving the dispersant in an aqueous medium such as water. Will be.

As a usage form of the heat storage body of the present invention, it is preferable to use a form of an emulsion-like water dispersion, and it may be used as a heat storage body in a form filled in a packaging material. Such a heat storage body will be used in the heat storage temperature range. It is preferable that such a heat storage body is stored and used in a heat storage tank constituting the heat storage device.
In the present invention, a method of using a heat storage body in which the dispersant concentration under the heat storage temperature of the dispersant aqueous solution is set in the above range in the heat storage temperature range is one of the preferred embodiments of the present invention. As the heat storage temperature range, for example, 0 to 20 ° C. when used as a cooling application, and 40 to 60 ° C. when used as a heating application, the temperature may be set according to the use conditions.

The heat storage body of the present invention is used for various heat storage devices in the form of such an emulsion or packaging state. As such a heat storage device, (1) the heat storage body is a heat transfer medium and And heat exchange, and (2) a heat storage tank in which the heat storage body is stored so that heat exchange of the heat medium can be performed.

As the heat storage device of (1) above, a heat storage device using a water-dispersed heat storage body is preferable, and the heat storage body circulates between the heat storage tank and the heat exchanger, or circulates outside the heat storage tank. The heat storage device etc. which heat-exchange by this are mentioned, The heat storage system which is a heat transfer medium system for district cooling and heating systems or a building air-conditioning system is formed by such a heat storage device.

The heat storage device of the above (2) includes a heat storage tank in which the heat storage body is stored, and can perform heat exchange of the heat medium, but a heat storage device in which the heat storage body is stored is preferable. A heat storage system is also formed by such a heat storage device.
As the heat storage device configured to store the heat storage body, a heat storage device provided with heat exchange means is preferably adapted to transfer heat energy to a heat medium circulating outside the heat storage device, for example, The heat storage tank that stores the heat storage body has a heat exchanger that performs heat exchange of the heat medium, or only the heat medium passes through the heat storage tank while the emulsion-like water dispersion is stored in the heat storage tank. And so on.
Such a heat storage device or heat storage system using the heat storage body of the present invention is also one aspect of the present invention.

As a preferable form of the heat storage device or heat storage system using the heat storage body of the present invention, the heat storage body or heat storage system provided with a line mixer is used, that is, the heat storage body in the form of an emulsion-like water dispersion, that is, the present invention. It is the thermal storage apparatus or thermal storage system to which the manufacturing method of invention is applied. By setting it as such a form, it is set as the thermal storage apparatus or thermal storage system which can maintain the dispersion | distribution state of a thermal storage body, and can be used suitably for the objectives, such as labor saving and efficiency improvement of air-conditioning energy, and environmental protection. It will be possible. Moreover, even when the dispersion of the oily substance in the heat storage tank collapses due to repeated phase change, it can be redispersed by using a line mixer attached to the heat storage device.

The present invention is also a heat storage system including a heat storage device using a heat storage body that essentially includes an oily substance having heat storage properties due to a phase change, an aqueous medium, and a dispersant, and the heat storage device is attached with a line mixer. It is also a heat storage system. Although it does not specifically limit as a heat storage body used for the said heat storage system, It is preferable that it is manufactured by the manufacturing method of this invention. By setting it as such a form, the effect similar to the above-mentioned heat storage system can fully be exhibited.

The heat storage body of the present invention has high fluidity at the heat storage temperature and has stability and durability, and it is easy to adjust the freezing point to improve the heat storage efficiency, or the solidification temperature and the melting temperature are close to each other. Because it is easy to solidify during heat storage, it is possible to lower the temperature during heat dissipation, and the amount of latent heat is increased to improve the heat storage performance, so that it can be used for large buildings such as office buildings and factories and for home use. It is excellent as a material constituting a heat storage device and a heat storage system for the purpose of labor saving and efficiency improvement of air conditioning energy and environmental protection.

The heat storage body of the present invention has the above-described configuration, is stable when used in the presence of a metal, and has improved stability in the presence of a metal element in the third period and / or the fourth period, It can be effectively used in a heat storage system that repeats solidification / melting.
A heat storage device or a heat storage system using such a heat storage body can be suitably used for the purpose of labor saving and efficiency of air-conditioning energy, environmental protection, and the like. By adjusting according to the purpose of use, it becomes easy to use as a heat storage body, and durability is improved. In addition, because the fluidity at the time of heat storage is improved, the system can be operated easily, so that the purpose of labor saving and efficiency of air conditioning energy for large buildings such as office buildings and factories and households, and for the purpose of environmental protection Therefore, it is excellent as a material constituting a heat storage device or a heat storage system.

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples. Unless otherwise specified, “part” means “part by weight” and “%” means “mass%”.

Example 1
An aqueous solution in which 1.5 parts of polyoxyethylene (ethylene oxide addition mole number 20) stearyl ether (manufactured by NOF Corporation: Nonion S-220) as nonionic surfactant is added to 48.0 parts of ion-exchanged water and dissolved in a container. And 50.0 parts of paraffin (tetradecane 19.4 mass%, pentadecane 73.5 mass%, hexadecane 6.9 mass%, heptadecane 0.2 mass%) distilled from kerosene which is an oily substance, A solution in which 0.5 part of Iwao Pharmaceutical Co., Ltd .: Sugar Wax A-10E) was dissolved was added. The mixture was emulsified using a stirrer (manufactured by Tokushu Kika Co., Ltd .: TK homomixer) to obtain an aqueous dispersion 1 in which paraffin was dispersed.
The volume average particle diameter of the aqueous dispersion 1 was 2.8 μm. Ion exchange water was added to the obtained aqueous dispersion to adjust the content of the oily substance to 10% by mass. And 1 mass% of iron oxide (III) was added, and the heat storage body 1 concerning this invention was obtained by this.
The obtained heat accumulator 1 was solidified at 4 ° C. and solidified / melted repeatedly at 12 ° C. for 250 times. As a result, separation of the oily material was not observed and the fluid was stable. Was also good.

Example 2
Tap water is added to the water dispersion 1 obtained in Example 1 to adjust the content of the oily substance to 10% by mass, and an iron test piece is immersed in the dispersion, thereby obtaining the heat storage body 2 according to the present invention. It was.
About the obtained heat storage body 2, the solidification of the oily substance was performed at 4 ° C., and the solidification / melting was repeated 700 times for melting at 12 ° C. Although the heat storage body turned brown due to iron rust, the oily substance was not separated and stable, and the fluidity was also good.
After the test, the iron content present in the heat storage element 2 was measured by plasma emission analysis (ICP analysis, Inductively Coupled Plasma: manufactured by HORIBA, Ltd., model name: ULTIMA), and found to be 157 ppm.

Example 3
An iron test piece was immersed in the aqueous dispersion 1 obtained in Example 1. This obtained the heat storage body 3 concerning this invention.
The obtained heat accumulator 3 was subjected to solidification of the oily substance at 4 ° C. and repeated 550 times of solidification / melting in which melting was performed at 12 ° C. Although the heat storage body turned brown due to iron rust, the oily substance was not separated and stable, and the fluidity was also good.
After the test, the iron content present in the heat accumulator 3 was measured by plasma emission analysis (ICP analysis, Inductively Coupled Plasma: manufactured by Horiba, Ltd., model name: ULTIMA), and found to be 176 ppm.

Comparative Example 1
Ion exchange water was added to the aqueous dispersion 1 obtained in Example 1, and the content of the oily substance was adjusted to 10% by mass. Thereby, the comparative heat storage body 1 concerning this invention was obtained.
About the obtained comparative heat storage body 1, when the oily substance was solidified at 4 ° C. and the solidification / melting was repeated at 12 ° C., the oily substance was separated at the 100th time.

Comparative Example 2
Without dipping the iron test piece in the aqueous dispersion 1 obtained in Example 1, the oily substance was solidified at 4 ° C., and the solidification / melting was repeated at 12 ° C. The oily substance was obtained at the 380th time. Separation was observed.

It is the schematic diagram which showed one Embodiment using the manufacturing apparatus 1 in the manufacturing method of this invention. It is the schematic diagram which showed one Embodiment using the manufacturing apparatus 11 in the manufacturing method of this invention. It is a schematic diagram which shows the mixing tank which manufactures the conventional heat storage material.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Manufacturing apparatus 2 Tank 3 Line mixer 4, 5, 6 Piping 11 Manufacturing apparatus 12 Tank 13 Line mixer 14, 15, 16 Piping

Claims (3)

A heat storage body essentially including an oily substance having heat storage properties due to a phase change, an aqueous medium, and a dispersant, wherein the heat storage body includes a metal element of the third period and / or the fourth period. Thermal storage body. The heat storage body according to claim 1, wherein the dispersant has a structure having an ethylene oxide addition mole number of 5 or more. A heat storage device or a heat storage system using the heat storage body according to claim 1 or 2.

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