JP2008045860A - Heat storage device - Google Patents

Abstract

An object of the present invention is to provide a heat storage device capable of storing heat at a higher temperature and increasing the amount of heat stored per heat storage material.
First and second heat transfer tubes 3 and 4 and first and second electric heaters 8 and 9 are disposed in a heat storage container 1 filled with a heat storage material 12, and the first and second heat transfer tubes 3, In the heat storage device that heats the above-mentioned heat medium by flowing the heat medium into the heat generating medium 4 and generates a high heat heat medium and steam and supplies them to the heat load, the heat storage material 12 is in the form of high purity electrofused magnesia The heat storage container 1 is provided with a heat insulating material around the heat storage container 1, and this heat insulating material is made of oxalic acid-aluminum-wool-felt, and the heat storage container 1 is made of ceramic or ceramic.
[Selection] Figure 1

Description

  The present invention relates to a heat storage device that uses surplus power such as midnight power.

  Conventionally, as a heat storage device that uses midnight power as a power source to level out the difference between daytime and midnight power loads, heat transfer tubes and electric heaters have been placed in the heat storage layer filled with heat storage materials, Electric power is supplied to the heater to store heat in the heat storage material, and during the heat output operation in the daytime, the heat medium is heated by flowing the heat medium into the heat transfer tube of the above-described heat storage device so that the high-temperature heat medium and steam are What produces | generates and supplies these to a thermal load is known (refer patent document 1).

In addition, the heat storage material described above includes granular (including powder) magnesia and molten salt (see Patent Document 2), and further includes at least one of nitrate and sulfite as the molten salt ( Patent Document 3) has been proposed.
JP 2000-292084 A JP 2000-161786 A JP-A-3-282101

  However, in the above prior art, since the heat storage material contains molten salt, it is easy to form a cavity inside, and it is difficult to store heat at a temperature higher than the evaporation temperature of the molten salt. Therefore, the amount of heat storage per heat storage material tends to be limited. Accordingly, in order to obtain a desired heat storage effect, the heat storage device tends to be large. In addition, molten salts such as nitrates and sulfites are expensive, which increases the manufacturing cost of the heat storage device. Furthermore, since the above-mentioned granular (including powdery) magnesia and molten salt are different in size and specific gravity, the molten salt is filled in the granular (including powdery) magnesia in a state where the molten salt is uniformly distributed. This is very difficult, and it is difficult to ensure accurate heat storage performance.

  In addition, since the conventional technology contains molten salt in the heat storage material, it is arranged from a liquid to a solid, that is, a phase change and contraction in the process of extracting heat from the heat storage device. Must be arranged to accommodate this.

  The present invention has been made from the actual situation in the prior art as described above, and an object thereof is to provide a heat storage device capable of storing heat at a higher temperature and increasing the amount of heat stored per heat storage material. is there.

  In order to achieve this object, a heat transfer tube and an electric heater are disposed in a heat storage container filled with a heat storage material, and the heat medium is heated by flowing the heat medium in the heat transfer tube to thereby heat the heat medium and In a heat storage device that generates steam and supplies these to a heat load, the heat storage material is made of only high-purity fused magnesia that is granular (including powder).

  Since the present invention configured as described above is only high-purity fused magnesia in which the heat storage material is granular (including powder) without providing a molten salt, the number of cavities formed inside can be reduced, Moreover, it is not limited by the evaporation temperature of the molten salt. Accordingly, it is possible to store heat at a higher temperature and to increase the amount of heat stored per heat storage material. Moreover, the restriction | limiting with respect to arrangement | positioning and direction of a heat exchanger tube and an electric heater like when providing molten salt can be eased.

  Further, the present invention is characterized in that, in the above invention, a heat insulating material is provided on an outer peripheral surface of the heat storage container, and the heat insulating material is made of oxalic acid-aluminum-wool-felt. In the present invention configured as above, the heat insulating effect can be enhanced by using oxalic acid-aluminum-wool-felt as the heat insulating material.

  In the present invention according to the present invention, the heat storage container is made of incoloy, earthenware, or ceramic. The present invention configured as described above can form a heat storage container excellent in heat resistance and heat insulation by forming the heat storage container from incoloy, earthenware, or ceramic.

  In the present invention, the electric heater is characterized in that the sheath material is made of incoloy, earthenware, or ceramic. The present invention thus configured can be further improved in heat resistance and heat insulation as an apparatus.

  In the present invention, since the heat storage material is composed of only high-purity fused magnesia in a granular form (including powder), heat storage at a higher temperature is possible, and the heat storage amount per heat storage material is increased. The heat storage device for obtaining a desired heat storage effect can be made smaller than before. Moreover, since no molten salt is provided, the manufacturing cost can be reduced. Furthermore, since the heat storage material is composed only of high-purity electrofused magnesia, it can be uniformly distributed in the heat storage container, and accurate heat storage performance can be ensured. In addition, restrictions on the arrangement and orientation of heat transfer tubes and electric heaters can be relaxed, making it easier to incorporate heat transfer tubes and electric heaters into heat storage containers, and reducing the number of manufacturing steps compared to conventional methods. Cost can be reduced.

  Hereinafter, the best mode for carrying out a heat storage device according to the present invention will be described with reference to the drawings.

[Configuration of this embodiment]
FIG. 1 is a longitudinal sectional view showing an embodiment of a heat storage device according to the present invention, FIG. 2 is a plan view of the present embodiment, and FIG. 3 is a sectional view corresponding to the arrow BB in FIG. 4 is an enlarged view of a main part of FIG. 5 is a plan view showing a heat transfer tube provided in the present embodiment, FIG. 6 is a front view of the heat transfer tube shown in FIG. 5, and FIG. 7 is a main part of a binding wire mounting portion provided in the present embodiment. FIG. 8 is an enlarged view of a main part of the attaching part of the binding wire shown in FIG. 6, and FIG. 9 is an enlarged vertical sectional view of the main part of the attaching part of the upper spacing plate provided in this embodiment. FIG. 10 is a front view of the electric heater provided in the present embodiment, and FIG. 11 is an enlarged cross-sectional view of the main part of the terminal portion of the electric heater shown in FIG.

  As shown in FIG. 1 and FIG. 2, the present embodiment includes a heat storage container 1 having a bottom and a cylindrical shape having a horizontal cross-sectional outline, and a lid (not shown) that closes the heat storage container 1. The first heat transfer tube 3 installed in the heat storage container 1 and wound in a coil shape whose diameter is slightly smaller than the distance between the opposing sides of the heat storage container 1 and whose height is slightly lower than the height of the heat storage container 1 is The heat transfer tube 3 is smaller than the heat transfer tube 3, for example, approximately 0.6 times in height and wound in a coil shape, and the inlet portion 4 </ b> A of the heat transfer tube shown in FIG. 3 is connected to the outlet portion 3 </ b> B of the first heat transfer tube 3. The connected 2nd heat exchanger tube 4 is provided.

  Furthermore, the recess 5A shown in FIG. 7 is formed on one side at intervals corresponding to the pitch of the first heat transfer tubes 3, and the holes 5B are formed at predetermined intervals in the longitudinal direction. The recesses 5A are formed outside the first heat transfer tubes 3. A recess 6A is formed on one side at intervals corresponding to the pitch of the plate-shaped first tube guide 5 and the second heat transfer tube 4 to be contacted, and holes 6B are formed at predetermined intervals in the longitudinal direction. 4 and the plate-like second tube guide 6 with which the recess 6A is in contact with the inside, and as shown in FIGS. 7 and 8, it is mounted between the hole 5B of the first guide 5 and the hole 6B of the second guide 6. A binding wire 7 is provided.

  Further, the first electric heat is U-shaped as shown in FIG. 10, and the distance between both ends is larger than that of the first heat transfer tube 3 and the second heat transfer tube 4, that is, the radius of the curved portion 8C shown in FIG. The heater 8 has the same U shape as the first electric heater 8, and includes a second electric heater 9 in which the radius of the curved portion 9 </ b> C is smaller than the radius of the curved portion 8 </ b> C of the first electric heater 8. In addition, as shown in FIG. 4, the linear portion 8A of the first electric heater 8 inserted into the receiving hole 11H of the outer heater support plate 11A described later and the first insertion hole 11H inserted into the receiving hole 11H of the inner heater support plate 11C described later. The interval between the linear portions 8B of the first electric heater 8 is set larger than the distance between the first heat transfer tube 3 and the second heat transfer tube 4, and the interval between the linear portions 9A and 9B of the second electric heater 9 is The distance is set to be approximately equal to the distance between the first heat transfer tube 3 and the second heat transfer tube 4. Further, as shown in FIGS. 1 and 2, the housing holes 10A, 10B and 10C for keeping the relative angles of the plurality of first and second electric heaters 8 and 9 constant, and the first transmission as shown in FIG. A heat transfer tube housing hole 10D into which the inlet 3A of the heat tube 3 and the outlet 4B of the second heat transfer tube 4 are inserted, a circular opening 10E formed in the center, and a triangular opening 10F formed in the corner are provided. The upper spacing holding plate 10 shown in FIG. 9 is provided.

  Moreover, it has the accommodation holes 11H of the first and second electric heaters 8 and 9 formed at equiangular intervals as shown in FIG. 4, and is located on the outermost side as shown in FIG. The heater support plate 11A is provided with three types of ring-shaped heater support plates 11 of a heater support plate 11A, an intermediate heater support plate 11B positioned in the middle, and an inner heater support 11C positioned at the innermost side. Furthermore, the thermal storage container 1 and the heat insulating material (illustration omitted) affixed on the outer peripheral surface of a lid | cover (illustration omitted) and the thermal storage material 12 with which the thermal storage container 1 was filled are provided.

In this embodiment, in particular, the above-described heat storage container 1 is made of incoloy, earthenware, or ceramic, and the above-described heat insulating material is made of oxalic acid-aluminum-wool-felt having a density of 96 to 128 kg / m ^3. Yes. The filled heat storage material 12 is made of particles (including powder) of high-purity fused magnesia (single crystal, generally white or transparent, specific gravity: 3.45 to 3.55).

  Further, the arrangement of the first electric heater 8 and the second electric heater 9 is determined by the above-described upper gap holding plate 10 and the three types of outer heater support plate 11A, middle heater support plate 11B, and inner heater support 11C. . Then, the straight portion 8A of the first electric heater 8 is inserted into the accommodation hole 11H of the outer heater support plate 11A, and the straight portion 8B is inserted into the accommodation hole 11H of the middle heater support plate 11B. As a result, the straight portion 8A of the first electric heater 8 is located outside the first heat transfer tube 3, the straight portion 8B is located inside the second heat transfer tube 4, and the straight portion 9A of the second electric heater 9 is provided. Is located outside the first heat transfer tube 3, and the straight portion 9B is located between the first heat transfer tube 3 and the second heat transfer tube 4, that is, inside the first heat transfer tube 3 and outside the second heat transfer tube 4. . As a result, the first electric heater 8 and the second electric heater 9 are alternately arranged radially at equal intervals.

  As shown in FIG. 11, the terminal portions of the first electric heater 8 and the second electric heater 9 described above include a U-shaped protective pipe 8D, an insulating washer 8E, a flat washer 8F, a spring washer 8G, a nut 8H, and a sleeve 8J. The heater body 8K and the like. As the first electric heater 8 and the second electric heater 9, in addition to a general sheathed heater, a sleeve 8J, a protective pipe 8D, etc. formed of incoloy, earthenware, or ceramic can be used.

[Operation of this embodiment]
In the present embodiment configured as described above, midnight or surplus power is supplied to the first and second electric heaters 8 and 9 to store heat in the heat storage material 12. When using the heat thus stored, a heat medium (liquid) is supplied into the first heat transfer tube 3 and heated by the heat storage material 12 while the heat medium flows through the tube, and then the second heat transfer tube. It is taken out from No. 4 and used as a heat source such as an absorption chiller / heater.

[Effect of this embodiment]
According to the present embodiment configured as described above, since the heat storage material 12 is made of only high-purity fused magnesia that is granular (including powder), the number of cavities formed inside can be reduced. And is not limited by the evaporation temperature of the molten salt. As a result, heat storage at a higher temperature is possible, the amount of heat stored per heat storage material 12 can be increased, and a heat storage device for obtaining a desired heat storage effect can be made smaller than before. Moreover, since no molten salt is provided, the manufacturing cost can be reduced. Furthermore, since the heat storage material 12 consists only of high purity electrofused magnesia, it can be uniformly distributed in the heat storage container 1, and accurate heat storage performance can be ensured. In addition, restrictions on the arrangement and orientation of the first and second heat transfer tubes 3 and 4 and the first and second electric heaters 8 and 9 can be relaxed, and the first and second heat transfer tubes 3 and 4 and the first, It becomes easy to incorporate the second electric heaters 8 and 9 into the heat storage container 1. Therefore, the number of manufacturing steps can be reduced, and this can also reduce the structural cost.

  Further, since the heat storage container 1 is made of incoloy, earthenware, or ceramic, it is possible to store heat at a temperature higher than the evaporation temperature (vaporizing temperature) of the molten salt when the molten salt is provided, which is effective for further miniaturization. There is. Furthermore, since the heat insulating material is made of oxalic acid-aluminum-wool-felt, the heat insulating effect can be enhanced.

  Further, as a result of storing heat at a higher temperature, a large temperature difference from the heat medium passing through the first and second heat transfer tubes 3 and 4 can be obtained, so that the heat transfer performance from the heat storage material 12 to the heat medium is improved.

  In particular, by arranging the first and second heat transfer tubes 3 and 4 and the first and second electric heaters 8 and 9 regularly, a space effective for heat storage, that is, a filling region of the heat storage material 12 in the heat storage container 1. The first and second electric heaters 8 and 9 and the first and second heat transfer tubes 3 and 4 can be distributed almost uniformly, and heat storage from the first and second electric heaters 8 and 9 to the heat storage material 12 Heat transfer from the heat storage material 12 to the heat medium in the first and second heat transfer tubes 3 and 4 can be performed efficiently. Moreover, since the U-shaped first and second electric heaters 8 and 9 are regularly arranged, positioning is easy and assembly is also easy.

It is a longitudinal cross-sectional view which shows one Embodiment of the thermal storage apparatus which concerns on this invention. It is a top view of this embodiment. It is sectional drawing corresponding to the BB arrow of FIG. It is a principal part enlarged view of FIG. It is a top view which shows the heat exchanger tube with which this embodiment is equipped. It is a front view of the heat exchanger tube shown in FIG. It is a principal part enlarged view of the mounting part of the wire for bundling with which this embodiment is equipped. It is a principal part enlarged view of the mounting part of the wire for binding shown in FIG. It is a principal part expanded vertical sectional view of the attaching part of the upper space | interval holding | maintenance board with which this embodiment is equipped. It is a front view of the electric heater with which this embodiment is equipped. It is a principal part expanded sectional view of the terminal part of the electric heater shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heat storage container 3 1st heat exchanger tube 4 2nd heat exchanger tube 7 Binding wire 8 1st electric heater 9 2nd electric heater 10 Upper space | interval holding plate 11 Heater support plate 12 Heat storage material

Claims (4)

A heat transfer tube and an electric heater are disposed in a heat storage container filled with a heat storage material, and the heat medium is heated by flowing the heat medium in the heat transfer tube to generate a high-temperature heat medium and steam, which are then heated. In the heat storage device that supplies the load,
A heat storage device, wherein the heat storage material is made of only high-purity fused magnesia that is granular (including powder).   The heat storage device according to claim 1, wherein a heat insulating material is provided on an outer peripheral surface of the heat storage container, and the heat insulating material is made of oxalic acid-aluminum-wool-felt.   3. The heat storage device according to claim 1 or 2, wherein the heat storage container is made of incoloy, earthenware, or ceramic.   3. The heat storage device according to claim 1, wherein the sheath material of the electric heater is made of incoloy, earthenware, or ceramic.

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