JP2013103979A - Latent heat storage body and latent heat storage unit, and first time melting method of latent heat storage body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a latent heat storage body and a latent heat storage unit in which an expensive heater or the like is not needed, the outflow of the latent heat storage body is not caused, and that enable the shortening of the required time of the first melting of the latent heat storage body, and to provide a first time melting method of the latent heat storage body.SOLUTION: The latent heat storage body 2 is composed of a fibrous material, is characterized in that the density after melting is larger than that of a heating medium 3, and by not being dissolved in the heating medium 3, and directly contacts with the heating medium 3 and exchanges heat. It is desirable that the bulk density/true density of the fibrous material is at least 0.001 and at most 0.7, and the fibrous material is a sugar alcohol. The first time melting method of the latent heat storage body 2 is characterized in that the latent heat storage body 2 is charged in a container 4 from an opening 7, then the heating medium 3 in which the temperature is made higher than the melting point of the latent heat storage body 2 is supplied into the container 4 from a heating medium inlet 5.

Description

  The present invention relates to a latent heat storage body, a latent heat storage apparatus, and an initial melting method of a latent heat storage body, and more specifically, a latent heat storage body that stores heat by exchanging heat in contact with a heat medium, and the specific gravity after melting is heat. The present invention relates to a latent heat storage body that is larger than the medium and does not dissolve in the heat medium, a latent heat storage apparatus using the latent heat storage body, and an initial melting method of the latent heat storage body using the latent heat storage body.

In recent years, the use of waste heat from factories and the like has become an effective means, while energy saving and reduction of greenhouse gas emissions, especially energy-derived carbon dioxide gas, are required.
In utilizing waste heat, a temporal or spatial mismatch between the demand and supply of heat becomes a problem. As a technique for solving this, heat from a waste heat source is stored as heat energy in a heat storage body (heat storage), heat energy is taken out according to demand (heat dissipation), and heat storage is mentioned.

There are two types of heat storage: latent heat storage that uses transition heat (usually latent heat of melting / solidification or evaporation / condensation by heating / cooling) that accompanies the primary phase transition of the heat storage body, and heat storage without using the transition heat. There is sensible heat storage that stores / dissipates heat according to temperature changes, but latent heat storage generally has a feature that the heat storage density is larger than that of sensible heat storage and the heat dissipation temperature is constant.
In a latent heat storage device, heat is transferred by a heat medium during heat storage and heat dissipation, but direct contact between the latent heat storage body and the heat medium provides a high heat storage / heat dissipation speed with a simple structure. Is widely done. Various such latent heat storage devices have been proposed. For example, Patent Document 1 can be cited.

In patent document 1, sodium acetate trihydrate is illustrated as a latent heat storage body, and it can be efficiently stored in a short time by using erythritol as a latent heat storage body.
In addition, various latent heat storage bodies that can be used in known latent heat storage devices have been proposed.
Among them, sugar alcohol is suitable for a latent heat storage because it has a large latent heat and is non-toxic. (For example, Patent Document 2)
In addition to a method using a high-temperature heat medium (for example, Patent Document 1), the latent heat storage body is melted by a method using a far infrared / middle infrared heater (Patent Document 3) or a method using a heater such as a sheathed heater (Patent Document 4). Proposed.

JP 2005-188916 Special Table Sho 63-500946 JP 2000-63813 A JP2000-274975

However, in the known latent heat storage body, since the shape of the heat storage material is generally powder or grain, the specific surface area is small, and the first melting with the high-temperature heat medium (operation for melting the heat storage body from the material) takes a long time. There was a problem.
In particular, when the component of the latent heat storage body is sugar alcohol, the shape of the heat storage body material is a fine powder, and therefore the latent heat storage body becomes latent heat accompanying the flow of the heat medium in the initial melting with a high temperature heat medium. It is easy to cause problems that flow out of the heat storage container, the supply amount of the high-temperature heat medium cannot be increased, the initial melting takes a long time, or the first melting with the high-temperature heat medium becomes impossible. There was also a problem.

In addition, when the initial melting is performed by heater heating, although the time required for the initial melting can be shortened, there is a problem that an expensive heater and power supply equipment are required for melting, which is uneconomical.
That is, in the prior art, there is a problem that the initial melting of the latent heat storage body takes a long time or the latent heat storage body flows out without expensive heater heating.

The present invention solves the above-described problems, does not require an expensive heater or the like, does not cause the latent heat storage body to flow out, and enables a reduction in the time required for the initial melting of the latent heat storage body and the latent heat storage body and latent heat storage device, and This was made for the purpose of providing an initial melting method of a latent heat storage body, and the gist thereof is as follows.
(1) A latent heat storage body that is composed of a fibrous material, has a higher density after melting than the heat medium, and does not dissolve in the heat medium, and exchanges heat by directly contacting the heat medium.
(2) Bulk density / true density of said fibrous material is 0.001 or more and 0.7 or less, The latent heat storage body as described in (1) characterized by the above-mentioned.
(3) The latent heat accumulator according to (1) or (2), wherein the fibrous material is a sugar alcohol.

According to the invention of (1), since the specific surface area of the latent heat storage body is increased and the heating by the high-temperature heat medium is accelerated, the latent heat storage body is entangled with each other and is not easily accompanied by the flow of the heat medium. Since the supply amount of the heat medium can be increased, the time required for the initial melting of the latent heat storage body can be shortened. Further, an expensive heater or the like is not necessary.
According to the invention of (2), the time required for the initial melting of the latent heat storage body can be further shortened by the synergistic effect of the increase in the specific surface area and the mutual entanglement.

According to the invention of (3), the problem that the latent heat storage body accompanies the flow of the heat medium due to the fine powder shape of the product, which has been a problem particularly with conventional sugar alcohols, is eliminated, Since the supply amount of the high-temperature heat medium can be increased, the time required for the initial melting of the latent heat storage body can be shortened.
(4) A latent heat storage device that exchanges heat by bringing a heat medium into contact with the latent heat storage body according to any one of (1) to (3) in a container that is a latent heat storage container, wherein the container includes the latent heat It has at least one opening that is an inlet of the heat storage body, at least one heat medium inlet that is an inlet of the heat medium, and at least one heat medium outlet that is an outlet of the heat medium. Latent heat storage device.

According to the invention of (4), since the specific surface area of the latent heat storage body is increased and the heating by the high temperature heat medium is accelerated, the latent heat storage body is intertwined with each other, so that the latent heat storage is accompanied by the flow of the heat medium. Since it becomes difficult to cause the trouble of flowing out of the container and the supply amount of the high-temperature heat medium can be increased, the time required for the initial melting of the latent heat storage body can be shortened. Further, an expensive heater or the like is not necessary.
(5) An initial melting method of a latent heat storage body performed using the latent heat storage apparatus according to (4), wherein the latent heat storage body according to any one of (1) to (3) is connected to the container from the opening. A first heat melting method for a latent heat storage body, wherein a heat medium having a temperature equal to or higher than the melting point of the latent heat storage body is supplied into the container from the heat medium inlet after charging into the container.
(6) An initial melting method of a latent heat storage body performed using the latent heat storage apparatus according to (4), wherein the temperature is equal to or higher than the melting point of the latent heat storage body according to any one of (1) to (3). An initial melting method for a latent heat storage body, comprising: supplying a heat medium from the inlet of the heat medium into the container and then charging the latent heat storage body into the container through the opening.
(7) In (5) or (6), the charging of the latent heat storage body according to any one of (1) to (3) to be melted for the first time is batched. An initial melting method of a latent heat accumulator characterized by being intermittently performed under supply.

Here, batching the charging means that the charging is performed in a plurality of times.
According to the invention of (5) or (6), the specific surface area of the latent heat storage body is increased, heating with a heat medium having a temperature equal to or higher than the melting point of the latent heat storage body is accelerated, and the latent heat storage bodies are intertwined with each other. As a result, it becomes difficult to cause a trouble that flows out of the latent heat storage container along with the flow of the heat medium, and the supply amount of the heat medium having a temperature equal to or higher than the melting point of the latent heat storage body can be increased. The time required for melting can be shortened. Further, an expensive heater or the like is not necessary.

      According to the invention of (7), since the melting state of the existing latent heat storage body can be observed and the supply amount of the heat medium and the additional charge amount of the latent heat storage body can be adjusted based on the result, the latent heat storage body It is possible to further reduce the time required for the initial melting of the.

  According to the present invention, a latent heat storage body that is composed of a fibrous material and has a higher density after melting than a heat medium and does not dissolve in the heat medium, a latent heat storage apparatus using the same, and a latent heat storage body using the same By adopting the initial melting method, it is possible to reduce the time required for the initial melting of the latent heat storage body without requiring an expensive heater or the like and without causing a problem of the outflow of the latent heat storage body.

It is a schematic sectional drawing which shows an example of the latent heat storage apparatus which concerns on this invention. It is a schematic sectional drawing which shows the latent heat storage body container in the apparatus of FIG. It is a schematic sectional drawing which shows the heat medium supply step in the apparatus of FIG. It is a schematic sectional drawing which shows the latent heat storage body charging step in the apparatus of FIG.

  An embodiment (abbreviated embodiment) for carrying out the present invention will be described with reference to FIGS. 1 is a schematic sectional view showing an example of a latent heat storage device according to the present invention, FIG. 2 is a schematic sectional view showing a latent heat storage body container in the device of FIG. 1, and FIG. 3 shows a heat medium supply stage in the device of FIG. It is a schematic sectional drawing. 1 to 3, 1 is a latent heat storage device, 2 is a latent heat storage body, 3 is a heat medium, 4 is a container (specifically a latent heat storage body container), 5 is a heat medium inlet, 6 is a heat medium outlet, and 7 is a heat medium outlet. It is an opening.

  The latent heat storage body 2 is composed of a fibrous material that has a higher density after melting than the heat medium and does not dissolve in the heat medium, and each fiber is gently entangled to form an aggregate (fiber aggregate). . The fiber assembly constituting the latent heat storage body 2 preferably has a bulk density / true density of 0.001 or more and 0.7 or less. If the bulk density / true density of the fibrous material is more than 0.7, the specific surface area becomes too small and the heat exchange rate with the heat medium 3 becomes insufficient, while if less than 0.001, the flow of the heat medium 3 This is because it easily flows out of the container 4. The bulk density / true density is more preferably 0.001 or more and 0.5 or less.

As the component of the latent heat storage body 2, a known component for a latent heat storage body can be used. Among them, sugar alcohol is preferable in that the latent heat is large and nontoxic.
As shown in FIG. 1, a latent heat storage device 1 according to the present invention is a latent heat storage device 1 in which a heat medium 3 is directly brought into contact with a latent heat storage body 2 to exchange heat in a container 4 that is a latent heat storage body container. The container 4 has at least one opening 7 that is an inlet of the latent heat storage body 2, at least one heat medium inlet 5 that is an inlet of the heat medium 3, and at least one that is an outlet of the heat medium 3. And a heat medium outlet 6.

The opening 7 is preferably configured to be openable and closable, and is preferably closed except when the latent heat storage body 2 is inserted to prevent heat dissipation or heat medium 3 dissipation.
FIG. 1 shows a stage in which the latent heat storage body 2 is inserted into the container 4, and the heat medium 3 is caused to flow into the container 4 from the heat medium inlet 5, and at the same time, flows out of the container 4 from the heat medium outlet 6. It was. Before reaching this stage, an initial melting method of the latent heat storage body 2 performed using the latent heat storage device 1 of FIG. 1 will be described below.

On the other hand, as shown in FIG. 2, the latent heat storage body 2 (which is solid at room temperature) is charged into the container 4 from the opening 7 and then the heat medium 3 is put into the latent heat storage body container.
On the other hand, as shown in FIG. 3, after supplying the heat medium 3 from the heat medium inlet 5 into the container 4, the latent heat storage body 2 is charged. At this time, when the temperature of the heat medium 3 supplied into the container 4 becomes equal to or higher than the melting point of the latent heat storage body 2, the latent heat storage body 2 is first melted.

  The latent heat storage body 2 is heated by the heat medium 3 having a temperature equal to or higher than the melting point of the latent heat storage body 2, and finally the latent heat storage body 2 is melted to complete the initial melting of the latent heat storage body 2. Since the latent heat storage body 2 before the first melting is a fiber assembly, the specific surface area is large and the heating with the high-temperature heat medium 3 becomes fast, and the fibers of the latent heat storage body 2 are entangled with each other. Since the amount of supply of the high-temperature heat medium 3 can be increased, the time required for this initial melting is shorter than before and expensive heater heating is not required.

In this initial melting process, the latent heat storage body 2 takes heat from the heat medium 3 and stores it in the latent heat storage body 2, so this initial melting process is also the first heat storage process. On the other hand, the heat medium 3 is deprived of heat by the latent heat storage body 2 and becomes a low-temperature heat medium 3 and eventually flows out of the container 4 from the heat medium outlet 6 as shown in FIG.
In the example of the first melting method described above, the heat medium 3 is supplied after the entire amount of the latent heat storage body 2 is charged, or the latent heat storage body 2 is charged after the heat medium 3 is sufficiently supplied. Instead, the charging of the latent heat storage body 3 to be melted for the first time is batched, and for example, as shown in FIG. After the initial melting, the latent heat storage body 2 may be charged intermittently under the supply of the heat medium 3. This example is an embodiment in an example described later. According to this, since the melting state of the existing latent heat storage body 2 is observed and the supply amount of the heat medium 3 and the additional charge amount of the latent heat storage body 2 can be adjusted based on the result, the latent heat storage body The time required for the first melting of 2 can be further shortened, which is preferable.

Next, the heat radiation / heat storage operation of the latent heat storage device 1 after the completion of the first melting will be described with reference to FIG.
In the heat radiation operation, the low-temperature heat medium 3 is caused to flow into the container 4 from the heat medium inlet 5, and the high-temperature heat medium 3 is caused to flow out of the container 4 from the heat medium outlet 6. The low-temperature heat medium 3 flowing into the container 4 contacts the latent heat storage body 2 while flowing inside the container 4, is heated by the latent heat storage body 2, becomes a high-temperature heat medium 3, and is discharged from the heat medium outlet 6. 4 flows out.

At the time of starting the heat radiation operation, the latent heat storage body 2 is in a liquid phase including a partial case. By continuing the heat radiation operation, the temperature of the latent heat storage body 2 and the heat medium 3 in the container 4 is lowered, and the latent heat is stored. When the temperature of the heat storage body 2 reaches the freezing point, the latent heat storage body 2 gradually solidifies and radiates the latent heat.
In the heat storage operation, the high-temperature heat medium 3 heated by heat from a waste heat source or the like flows into the container 4 from the heat medium inlet 5, and the low-temperature heat medium 3 flows out of the container 4 from the heat medium outlet 6. . The heat medium 3 flowing into the latent heat storage container 4 contacts the latent heat storage body 2 while flowing inside the latent heat storage container 4, heats the latent heat storage body 2, and flows out of the latent heat storage container 4 from the heat medium outlet 6. To do.

At the start of the heat storage operation, the latent heat storage body 2 is in a solid phase, and by continuing the heat storage operation, the temperature of the latent heat storage body 2 and the heat medium 3 in the container 4 rises, and the temperature of the latent heat storage body 2 is increased. When the temperature reaches the melting point, the latent heat storage body 2 gradually melts and stores latent heat.
As described above, the heat storage / heat radiation operation is repeated, heat from a waste heat source or the like is stored as heat energy in the latent heat storage body 2, and the heat energy is extracted and used according to demand.

4 kg of erythritol (manufactured by Cargill), which is one type of sugar alcohol, was heated and melted in dry nitrogen gas and extruded from the pores to form a fiber. These were collected and adjusted to a fiber assembly having an average bulk density of 600 kg / m ³ (bulk density / true density = 0.4) to obtain a latent heat storage body 2.
Using the latent heat storage device 1 of the apparatus form shown in FIG. 1, 2.5 kg of the latent heat storage body 2 is charged into a container 4 having an internal volume of 5 L, and a heat medium of 130 ° C. (= melting point of the latent heat storage body 2 + 12 ° C.) 3 is supplied into the container 4 at a cross-sectional average speed of 0.5 cm / s in the container 4, the latent heat storage body 2 does not flow out of the container 4 along with the flow of the heat medium 3, and latent heat is generated in 20 minutes. Most of the heat storage body 2 melted. The average cross-sectional velocity in the container 4 is defined by the flow rate of the heat medium 3 supplied to the container 4 / the horizontal sectional area (internal dimensions) of the container 4. As the heat medium 3, NeoSK-OIL1400 (manufactured by Soken Techniques) was used.

  Next, in the latent heat storage device 1 (see FIG. 4) in which the 2.5 kg latent heat storage body 2 is melted, the 130 ° C. heat medium 3 is placed in the container 4 at an average cross-sectional speed of 0.2 cm / s in the container 4. When the latent heat storage body 2 is intermittently introduced (charged) from the opening 7 at the top of the container 4 so that the amount of the unmelted latent heat storage body 2 is approximately constant, the latent heat storage is performed in 40 minutes. The charging and melting (initial melting) of body 2 was completed.

DESCRIPTION OF SYMBOLS 1 Latent heat storage apparatus 2 Latent heat storage body 3 Heat medium 4 Container (latent heat storage body container)
5 Heat medium inlet 6 Heat medium outlet 7 Opening

Claims (7)

  A latent heat storage body that is made of a fibrous material, has a higher density after melting than a heat medium, and does not dissolve in the heat medium, and exchanges heat in direct contact with the heat medium.   The latent heat storage body according to claim 1, wherein a bulk density / true density of the fibrous material is 0.001 or more and 0.7 or less.   The latent heat storage body according to claim 1, wherein the fibrous material is a sugar alcohol.   A latent heat storage device that exchanges heat by bringing a heat medium into contact with the latent heat storage body according to any one of claims 1 to 3 in a container that is a latent heat storage container, wherein the container is an inlet of the latent heat storage body A latent heat storage device, comprising: at least one opening that is, at least one heat medium inlet that is an inlet of the heat medium, and at least one heat medium outlet that is an outlet of the heat medium. .   It is the initial melting method of the latent heat storage body performed using the latent heat storage apparatus of Claim 4, Comprising: After charging the latent heat storage body in any one of Claims 1-3 into the said container from the said opening part An initial melting method of a latent heat storage body, wherein a heat medium having a temperature equal to or higher than the melting point of the latent heat storage body is supplied from the inlet of the heat medium into the container.   It is the initial melting method of the latent heat storage body performed using the latent heat storage apparatus of Claim 4, Comprising: The heat medium made into temperature more than melting | fusing point of the latent heat storage body in any one of Claims 1-3 is said heat | fever An initial melting method of a latent heat storage body, wherein the latent heat storage body is charged into the container through the opening after being supplied into the container from a medium inlet.   In Claim 5 or 6, the charging of the latent heat storage body according to any one of claims 1 to 3 to be melted for the first time is batched, and the batched charging is intermittently performed under the supply of the heat medium. The first melting method of the latent heat storage body characterized by the above.

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