Chemical heat storage device

Abstract

To provide a chemical heat storage device capable of suppressing a reduction in the heat transfer performance between a heat storage body and a heat transfer member and of suppressing the generation of thermal stress in the heat transfer member.SOLUTION: A chemical heat storage device 1 includes a reactor 2 in which a storage part 22 is defined, a heat storage body 4 arranged in the storage part 22, a heat transfer member 5 arranged in the storage part 22 and having a heat transfer surface 500 for giving / taking heat to / from the heat storage body 4, and a thermal stress suppression member 94 arranged between the heat storage body 4 and the heat transfer surface 500 for suppressing the generation of thermal stress in the heat transfer member 5. The thermal stress suppression member 94 has lubricant 940 arranged on the heat transfer surface 500 and having higher heat conductivity than the heat storage body 4, and assists in the thermal deformation of the heat transfer member 5 using the lubrication property of the lubricant 940 to suppress the generation of the thermal stress in the heat transfer member 5.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present disclosure relates to a chemical heat storage device capable of reversibly storing and releasing heat by utilizing heat of a chemical reaction. [Background technology]

[0002] Patent Document 1 discloses a heat exchanger including a vessel body, a plurality of baffles, and a plurality of heat transfer tubes. The vessel body extends in a horizontal direction. An inlet and an outlet are provided on a side peripheral wall of the vessel body. The heat transfer tube is accommodated inside the vessel body. The heat transfer tube extends in a horizontal direction. A plurality of baffles are accommodated inside the vessel body. The baffles are spaced apart from each other at a predetermined interval and stand vertically from the inner surface of the vessel body. The baffles support the side peripheral wall of the heat transfer tube. A first liquid flows inside the vessel body from the inlet to the outlet, bypassing the baffles. A second liquid flows inside the heat transfer tube. Heat exchange is performed between the first liquid and the second liquid through the side peripheral wall of the heat transfer tube. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 46-28750 Summary of the Invention [Problem to be solved by the invention]

[0004] Assume that the heat exchanger of the document is converted to a chemical heat storage device. In this case, the heat storage body is disposed inside the vessel body. That is, the heat storage body is filled in the gaps between the heat transfer tube and the baffle plate inside the vessel body. Therefore, when the heat storage body expands due to a chemical reaction, the heat storage body is pressed against the heat transfer tube. Therefore, the heat transfer performance between the heat storage body and the heat transfer tube can be improved. However, in this case, the thermal deformation of the heat transfer tube is hindered. Therefore, thermal stress occurs in the heat transfer tube. Here, in order to suppress the generation of thermal stress, it is sufficient to suppress the heat storage body from being pressed against the heat transfer tube. However, in this case, the heat transfer performance between the heat storage body and the heat transfer tube is reduced. In this way, there is a trade-off between suppressing the reduction in heat transfer performance between the heat storage body and the heat transfer tube and suppressing the generation of thermal stress in the heat transfer tube.

[0005] Therefore, an object of the present disclosure is to provide a chemical heat storage device capable of suppressing a decrease in heat transfer between a heat storage body and a heat transfer member, and capable of suppressing the occurrence of thermal stress in the heat transfer member. [Means for solving the problem]

[0006] (1) In order to solve the above problems, the chemical heat storage device of the present disclosure includes a reactor that divides an accommodation section into an interior thereof, a heat storage body disposed in the accommodation section, a heat transfer member disposed in the accommodation section and having a heat transfer surface that transfers heat to and from the heat storage body, and a thermal stress suppression member disposed between the heat storage body and the heat transfer surface and suppressing the occurrence of thermal stress in the heat transfer member, the thermal stress suppression member being disposed on the heat transfer surface and having a lubricant having a higher thermal conductivity than the heat storage body, and utilizing the lubricating properties of the lubricant to assist the thermal deformation of the heat transfer member and suppress the occurrence of thermal stress in the heat transfer member. Here, the "thermal deformation" of the heat transfer member includes deformation and movement (displacement) of the heat transfer member.

[0007] According to the chemical heat storage device of the present disclosure, a thermal stress suppression member is disposed between the heat storage body and the heat transfer surface. The lubricant of the thermal stress suppression member is disposed on the heat transfer surface. Therefore, the lubricating property of the lubricant can be utilized to assist the thermal deformation of the heat transfer member. In other words, the lubricating property of the lubricant can be utilized to suppress the thermal deformation of the heat transfer member from being hindered by the heat storage body. Therefore, the generation of thermal stress in the heat transfer member can be suppressed. In addition, the lubricant has a higher thermal conductivity than the heat storage body. Therefore, the decrease in the heat transfer performance between the heat storage body and the heat transfer member can be suppressed. In this way, according to the chemical heat storage device of the present disclosure, the decrease in the heat transfer performance between the heat storage body and the heat transfer member can be suppressed, and the generation of thermal stress in the heat transfer member can be suppressed.

[0008] (2) In the above configuration (1), it is preferable that the thermal stress suppression member is arranged between the lubricant and the heat storage body and has a film member having a higher thermal conductivity than the heat storage body. According to this configuration, the film member is arranged between the lubricant and the heat storage body. Therefore, it is possible to suppress direct contact between the lubricant and the heat storage body. Also, it is possible to suppress the lubricant from being mixed into the heat storage body. Also, the film member has a higher thermal conductivity than the heat storage body. Therefore, it is possible to suppress a decrease in heat transfer between the heat storage body and the heat transfer member.

[0009] (2-1) In the above configuration (2), it is preferable that the lubricant has fluidity. Here, lubricants that have "fluidity" include, for example, lubricants in powder, liquid, and paste form. Powder lubricants include lubricants that are in powder form from the time they are placed in the storage unit, and lubricants that were in a lump form when they were placed in the storage unit but have since become powdered due to wear and the like. With this configuration, the lubricant itself flows (deforms), thereby improving lubricity.

[0010] (3) In any of the above configurations, it is preferable that the volume of the storage section is smaller than the volume of the heat storage body after expansion due to a chemical reaction. According to this configuration, it is possible to suppress the occurrence of dead space in the storage section. Also, according to this configuration, when the heat storage body expands, it is possible to press the heat storage body against the heat transfer member with the thermal stress suppression member. Therefore, it is possible to improve the heat transfer between the heat storage body and the heat transfer member. Even if the pressure contact force of the heat storage body against the heat transfer member is high as in this configuration, it is possible to assist the thermal deformation of the heat transfer member by the thermal stress suppression member between the heat storage body and the heat transfer surface. Therefore, it is possible to suppress the occurrence of thermal stress in the heat transfer member. Effect of the Invention

[0011] According to the chemical heat storage device of the present disclosure, it is possible to suppress a decrease in heat transfer between the heat storage body and the heat transfer member, and also to suppress the occurrence of thermal stress in the heat transfer member. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a perspective view of the chemical heat storage device of the first embodiment. [Diagram 2] FIG. 2 is an exploded perspective view of the chemical heat storage device. [Diagram 3] FIG. 3 is a partially transparent perspective view of the chemical heat storage device. [Figure 4] FIG. 4 is a cross-sectional view of the chemical heat storage device taken in the front-rear direction. [Diagram 5] FIG. 5 is an enlarged view of the area within the frame V in FIG. [Figure 6] FIG. 6 is a cross-sectional view taken along the line VI-VI in FIG. [Figure 7] FIG. 7 is an enlarged view of the area within box VII in FIG. [Figure 8] FIG. 8 is an enlarged view of the area VIII in FIG. [Figure 9] FIG. 9 is a partial cross-sectional view in the front-rear direction of the chemical heat storage device when the heat transfer member is thermally deformed. [Figure 10]FIG. 10 is a partial cross-sectional view in the front-rear direction of a chemical heat storage device that does not include a thermal stress suppression member. [Figure 11] FIG. 11 is a partial cross-sectional view in the front-rear direction of the chemical heat storage device of the second embodiment. [Figure 12] FIG. 12 is a partial cross-sectional view in the front-rear direction of the chemical heat storage device of the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the chemical heat storage device of the present disclosure will be described. In the following figures, the front-rear direction corresponds to the axial direction (extension direction of the cylindrical axis) of the inner container and the outer container. At least one of the up-down direction and the left-right direction corresponds to the axial direction (direction perpendicular to the axial direction, cross-sectional direction, radial direction) of the inner container and the outer container.

[0014] First Embodiment FIG. 1 shows a perspective view of the chemical heat storage device of this embodiment. FIG. 2 shows an exploded perspective view of the chemical heat storage device. FIG. 3 shows a partially see-through perspective view of the chemical heat storage device. FIG. 4 shows a cross-sectional view in the front-rear direction (axial direction) of the chemical heat storage device. FIG. 5 shows an enlarged view of the inside of frame V in FIG. 4. FIG. 6 shows a cross-sectional view in the VI-VI direction (direction perpendicular to the axis) of FIG. 4. Note that FIG. 4 corresponds to the cross section in the IV-IV direction of FIG. 6.

[0015] In FIG. 1, the inner container 2, the heat transfer member 5 (curved pipe section 51), the heat transfer member mounting plate 81, and the indirect support member 87 inside the outer container 3 are shown by dotted lines. In FIG. 2, the through hole 201 of the inner container 2 is omitted. In FIG. 3, the members (heat transfer member 5 with thermal stress suppression member 94, and direct support member 7) inside the inner container 2 (accommodation section 22) are shown through the inner container 2, the heat transfer member mounting plate 81, and the indirect support member 87. The thermal stress suppression member 94 is shown by dotted hatching. The through hole 201 and the heat storage body 4 are omitted. In FIG. 5, the front-rear direction intermediate portion of the inner container 2 is omitted. In FIGS. 4 to 6, the radial thickness of the thermal stress suppression member 94 (the radial direction of a circle centered on the tube axis A3 of the straight pipe section 50) is emphasized. That is, in reality, the thermal stress suppression member 94 has a smaller radial thickness than the side peripheral wall portion of the straight pipe section 50. However, the relationship in thickness between the thermal stress suppression members 94 and the heat transfer member 5 is not particularly limited.

[0016] [Configuration of chemical heat storage device] First, the configuration of the chemical heat storage device 1 of this embodiment will be described. As shown in Fig. 1 to Fig. 6, the chemical heat storage device 1 of this embodiment includes an inner container 2, an outer container 3, a heat storage body 4, a plurality of heat transfer members 5, a plurality of direct support members 7, a reaction medium supply and discharge pipe 80, a heat transfer member mounting plate 81, a heat medium supply and discharge cylinder 82, a partition wall 83, a heat medium supply pipe 84, a heat medium discharge pipe 85, an end plate 86, a plurality of indirect support members 87, two legs 88, and a plurality of thermal stress suppression members 94. The inner container 2 is included in the concept of "reactor" in this disclosure.

[0017] (Inner container 2) As shown in Figs. 2, 4 and 6, the inner container 2 is made of metal, extends in the front-rear direction (horizontal direction), and has a bottomed cylindrical shape that opens to the front. The cylindrical axis A1 of the inner container 2 extends in the front-rear direction. The inner container 2 includes walls (side peripheral wall portion 20, end wall portion 21) and a storage portion 22. The side peripheral wall portion 20 has a cylindrical shape that extends in the front-rear direction. The end wall portion 21 seals the rear end opening of the side peripheral wall portion 20. A plurality of insertion holes 210 are formed in the end wall portion 21. As shown in Figs. 1, 4 to 6, a plurality of through holes (reaction medium flow paths) 201 are formed in the side peripheral wall portion 20. The through holes 201 communicate with the outside of the inner container 2 (an outer flow path 32 described later) and the storage portion 22. The size (hole diameter) of the through-holes 201 is set to a size that allows water vapor to pass through but does not allow the passage of the heat storage material particles of the heat storage body 4. The storage section 22 is disposed inside the wall. The storage section 22 is partitioned by the inner surface of the wall.

[0018] (Outer container 3, legs 88) As shown in Figs. 1, 2, 4, and 6, the outer container 3 is made of metal, extends in the front-rear direction, and has a bottomed cylindrical shape that opens to the front. The outer container 3 covers the inner container 2 from the outside. The cylindrical axis A2 of the outer container 3 extends in the front-rear direction. The cylindrical axis A1 and the cylindrical axis A2 are coincident. The outer container 3 includes a side peripheral wall portion 30 and an end wall portion 31. The side peripheral wall portion 30 has a cylindrical shape that extends in the front-rear direction. The end wall portion 31 seals the rear end opening of the side peripheral wall portion 30. The end wall portion 31 has a mounting hole 310. The outer container 3 defines an outer flow path 32. Specifically, the outer flow path 32 is defined between the inner surface of the outer container 3 and the outer surface of the inner container 2. The two legs 88 support the outer container 3, i.e., the chemical heat storage device 1, from below.

[0019] (Heat storage body 4) As shown in Figures 4 to 6, the heat storage body 4 is filled in the storage section 22. The heat storage body 4 contains heat storage material particles made of a chemical heat storage material (calcium oxide after dehydration, calcium hydroxide after hydration) and clay minerals. The heat storage body 4 can expand and contract due to chemical reactions (hydration reaction, dehydration reaction) with water vapor (H2O) which is a reaction medium.

[0020] The volume of the storage section 22 (more specifically, the portion of the storage section 22 in which components (multiple heat transfer members (heat transfer members with thermal stress suppression members 94) 5, multiple direct support members 7) are not arranged) is smaller than the volume of the heat storage body 4 after expansion due to the hydration reaction. Therefore, after expansion (after the hydration reaction), the heat storage body 4 is pressed against the inner surface of the inner container 2 (the surface that defines the storage section 22), the outer surfaces of the multiple thermal stress suppression members 94 described below, and the outer surfaces of the multiple direct support members 7.

[0021] (Heat transfer material 5) As shown in Figs. 3 to 6, the heat transfer member 5 is made of metal and has a U-shaped circular tube shape. That is, the heat transfer member 5 includes two straight pipe sections 50 and a curved pipe section 51. The straight pipe sections 50 extend in the front-rear direction. The two straight pipe sections 50 are arranged opposite each other in the up-down direction. As shown in Fig. 5, the front end of the straight pipe section 50 of the heat transfer member is fixed to a mounting hole 810 of a heat transfer member mounting plate 81 described later. On the other hand, the rear end of the straight pipe section 50 penetrates an insertion hole 210 of the end wall section 21 and protrudes to the rear side of the end wall section 21. A heat transfer surface 500 is set in a section of the outer circumferential surface of the straight pipe section 50 that is accommodated in the accommodation section 22.

[0022] As shown in Figs. 3 and 4, the curved pipe section 51 extends in a C-shape bulging rearward. The curved pipe section 51 connects the rear ends of the two straight pipe sections 50 together. The curved pipe section 51 is disposed in the outer flow passage 32. The heat transfer member 5 defines a heat medium flow passage 52 therein. The heat medium can flow through the heat medium flow passage 52. The heat medium transfers heat to and from the heat storage body 4 via a thermal stress suppression member 94 (described later) and a wall of the straight pipe section 50 of the heat transfer member 5. As shown in Fig. 6, in the accommodation section 22, the straight pipe sections 50 of the multiple heat transfer members 5 are aligned in the up-down and left-right directions.

[0023] (Direct support member 7) As shown in Figs. 3 and 4, the direct support member 7 is disposed in the accommodation section 22. The multiple direct support members 7 are arranged side by side in the front-rear direction at a predetermined interval. The multiple direct support members 7 divide the accommodation section 22 into multiple chambers 220 lined up in the front-rear direction. The straight pipe section 50 (straight pipe section with thermal stress suppression member 94) of the heat transfer member 5 is inserted into the support hole 70 of the direct support member 7. The support hole 70, i.e., the direct support member 7, supports the heat transfer member 5 via the thermal stress suppression member 94.

[0024] (Thermal stress suppression components 94) Fig. 7 shows an enlarged view of the area within frame VII in Fig. 5. Fig. 8 shows an enlarged view of the area within frame VIII in Fig. 6. As shown in Figs. 5 to 8, the thermal stress suppression member 94 is disposed in a section corresponding to the heat transfer surface 500 of the straight pipe section 50. The thermal stress suppression member 94 assists in the thermal deformation (expansion and contraction in the front-rear direction) of the straight pipe section 50. The thermal stress suppression member 94 suppresses the occurrence of thermal stress in the straight pipe section 50, i.e., the heat transfer member 5.

[0025] The thermal stress suppression member 94 has a cylindrical shape extending in the front-rear direction along the straight pipe portion 50. As shown in Figs. 7 and 8, the thermal stress suppression member 94 includes a lubricant 940 and a film member 941. The lubricant 940 is made of graphite (carbon) and is in the form of powder. The lubricant 940 is disposed over the entire surface (over the entire circumferential length and the entire front-rear length) of the heat transfer surface 500. The lubricant 940 has fluidity. The lubricant 940 has self-lubricating properties. The lubricant 940 has a higher thermal conductivity than the heat storage body 4.

[0026] The film member 941 is made of stainless steel (metal) foil and has a cylindrical shape extending in the front-rear direction. The film member 941 has a higher thermal conductivity than the heat storage body 4. The film member 941 is disposed between the lubricant 940 and the heat storage body 4. The film member 941 covers the lubricant 940 from the outside in the radial direction (the radial direction of a circle centered on the tube axis A3 of the straight tube section 50).

[0027] As shown in FIG. 5, the front end of the film member 941 (sealing portion that seals the lubricant 940) is accommodated in the mounting hole 810 of the heat transfer member mounting plate 81. The straight pipe section 50 is fixed to the mounting hole 810 via the front end of the film member 941. As shown in FIG. 5 and FIG. 7, the rear end of the film member 941 (sealing portion that seals the lubricant 940) is accommodated in the insertion hole 210 of the end wall section 21. The rear end of the film member 941 is not fixed to the outer circumferential surface of the straight pipe section 50. For this reason, the straight pipe section 50, i.e., the heat transfer member 5, can expand and contract in the front-rear direction with respect to the film member 941, i.e., the thermal stress suppression member 94, from the front end (portion accommodated and fixed in the mounting hole 810) as the base point.

[0028] (Reaction medium supply and exhaust pipe 80, heat transfer member mounting plate 81, heat medium supply and exhaust cylinder 82, partition wall 83, heat medium supply pipe 84, heat medium exhaust pipe 85, end plate 86) As shown in FIG. 1, FIG. 2, and FIG. 4, the reaction medium supply and discharge pipe 80 is attached to the mounting hole 310 of the outer container 3. The heat transfer member mounting plate 81 seals the front openings of the inner container 2 and the outer container 3. The heat transfer member mounting plate 81 has a plurality of mounting holes 810. As described above, the front end of the straight tube portion 50 of the heat transfer member 5 is attached to the mounting hole 810 via the front end of the film member 941. The mounting hole 810, that is, the heat transfer member mounting plate 81, fixes and supports the heat transfer member 5. The heat transfer medium supply and discharge tube 82 is disposed in front of the heat transfer member mounting plate 81. Two mounting holes 820 are opened at both upper and lower ends of the side peripheral wall of the heat transfer medium supply and discharge tube 82. The partition wall 83 divides the internal space of the heat transfer medium supply and discharge tube 82 into a lower supply chamber 830 and an upper discharge chamber 831. The supply chamber 830 is connected to the lower mounting hole 820, and the discharge chamber 831 is connected to the upper mounting hole 820. The heat medium supply pipe 84 is attached to the lower mounting hole 820 of the heat medium supply and discharge cylinder 82, and the heat medium discharge pipe 85 is attached to the upper mounting hole 820 of the heat medium supply and discharge cylinder 82. An end plate 86 seals the front end opening of the heat medium supply and discharge cylinder 82.

[0029] (Indirect support member 87) As shown in Figs. 1 to 4, the indirect support member 87 is disposed between the outer peripheral surface of the side peripheral wall portion 20 of the inner container 2 and the inner peripheral surface of the side peripheral wall portion 30 of the outer container 3. The multiple indirect support members 87 are disposed at predetermined intervals in the front-rear direction. The outer peripheral surface of the indirect support member 87 is provided with multiple openings 870 recessed radially inward. Through the openings 870, the respective portions of the outer flow path 32 communicate with each other in the front-rear direction. The indirect support member 87 supports the inner container 2.

[0030] (Reaction medium route R1, heat transfer medium route R2) As shown in Figures 4 to 6, a reaction medium route R1 for water vapor is set between the outside of the chemical heat storage device 1 and the heat storage body 4 of the storage section 22, passing through a reaction medium supply / discharge pipe 80, an outer flow path 32, and a through hole 201 from the outside toward the heat storage body 4.

[0031] As shown in Figures 4 to 6, a heat medium route R2 for the heat medium is set between the heat medium supply pipe 84 and the heat medium discharge pipe 85, and runs from the heat medium supply pipe 84 to the heat medium discharge pipe 85 through the supply chamber 830, the heat medium flow path 52, and the discharge chamber 831.

[0032] [Trends in chemical heat storage devices] Next, the operation of the chemical heat storage device 1 of this embodiment will be described. As described above, the heat storage body 4 contains heat storage material particles made of a chemical heat storage material (calcium oxide after dehydration, calcium hydroxide after hydration) and clay minerals. Here, a granulated body containing a plurality of heat storage material particles is referred to as a "heat storage material granule." Also, a state in which the heat storage body 4 contained in the containing section 22 has not yet undergone a hydration reaction is referred to as an "initial state."

[0033] (During heat release and hydration reaction) In the initial state, the heat storage material particles in the heat storage material granules of the heat storage body 4 are made of calcium oxide. During heat release, water vapor is supplied to the entire heat storage body 4 via the reaction medium route R1 shown in Figures 4 to 6. By supplying water vapor, the chemical heat storage material (calcium oxide) of the heat storage body 4 releases heat through the following hydration reaction, and becomes calcium hydroxide. Note that Q1 is the amount of heat release. CaO+H2O→Ca(OH)2+Q1 The hydration reaction causes the heat storage body 4 to expand and come into pressure contact with the inner surface of the inner container 2 (the surface that defines the storage section 22), the outer surface of the thermal stress suppression member 94 attached to the straight pipe section 50, and the outer surface of the direct support member 7. Heat Q1 generated by the hydration reaction moves to the heat medium in the heat medium flow path 52 via the heat storage body 4, the direct support member 7, the thermal stress suppression member 94, and the wall of the straight pipe section 50. The heat medium heated by the heat Q1 flows out to the outside via the heat medium route R2.

[0034] (During heat storage and dehydration reaction) During heat storage, a high-temperature heat medium is caused to flow through the heat medium route R2 shown in Figures 4 to 6. The heat of the heat medium is transferred to the heat storage body 4 via the wall of the straight pipe section 50, the thermal stress suppression member 94, and the direct support member 7. The chemical heat storage material (calcium hydroxide) of the heat storage body 4 heated by the heat stores heat and becomes calcium oxide through the following dehydration reaction. Note that Q2 is the amount of heat storage. Ca(OH)2+Q2→CaO+H2O Water vapor (H2O) generated by the dehydration reaction is discharged to the outside of the chemical heat storage device 1 via the reaction medium route R1 (the opposite direction to the arrow direction shown in Figs. 4 and 5).

[0035] [Effects] Next, the effect of the chemical heat storage device 1 of this embodiment will be described. Fig. 9 shows a partial cross-sectional view in the front-rear direction of the chemical heat storage device of this embodiment when the heat transfer member is thermally deformed. Fig. 10 shows a partial cross-sectional view in the front-rear direction of the chemical heat storage device not provided with a thermal stress suppression member. Note that Figs. 9 and 10 show a part corresponding to frame VII in Figs. 5 and 7.

[0036] The heat transfer member 5 is likely to expand (thermally deform) backward from the heat transfer member mounting plate 81 shown in FIG. 3 due to the heat generated during heat dissipation and heat storage. However, as shown in FIGS. 4 to 6, the heat storage body 4 is filled in the accommodation section 22. For this reason, as shown in FIG. 10, if the chemical heat storage device 1 does not include a thermal stress suppression member 94, the heat storage body 4 will bite (adhere) to the heat transfer surface 500 of the straight pipe section 50. For this reason, the sliding resistance between the heat transfer surface 500 and the heat storage body 4 increases, and the thermal deformation of the straight pipe section 50 is restricted. Therefore, thermal stress is likely to occur in the straight pipe section 50.

[0037] In contrast, as shown in FIG. 9, according to the chemical heat storage device 1 of this embodiment, a thermal stress suppression member 94 is disposed between the heat storage body 4 and the heat transfer surface 500. The lubricant 940 of the thermal stress suppression member 94 is disposed on the heat transfer surface 500. Therefore, by utilizing the lubricating property of the lubricant 940 (self-lubricating property of graphite, fluidity of particles constituting the powder), it is possible to reduce the sliding resistance between the heat transfer surface 500 and the heat storage body 4. Therefore, it is possible to assist the thermal deformation of the straight pipe section 50. In other words, it is possible to suppress the thermal deformation of the straight pipe section 50 from being hindered by the heat storage body 4. Therefore, it is possible to suppress the occurrence of thermal stress in the straight pipe section 50.

[0038] Furthermore, the lubricant 940 has a higher thermal conductivity (for example, thermal conductivity at a temperature of 300K) than the heat storage body 4. Therefore, it is possible to suppress a decrease in the heat transferability between the heat storage body 4 and the straight pipe section 50 (specifically, the heat transferability between the heat storage body 4 and the heat medium flowing through the heat medium flow path 52). Furthermore, compared to a case where the heat storage body 4 is arranged in the arrangement space of the lubricant 940 (see FIG. 10), it is possible to improve the heat transferability between the heat storage body 4 and the straight pipe section 50. In this way, according to the chemical heat storage device 1 of this embodiment, it is possible to suppress a decrease in the heat transferability between the heat storage body 4 and the heat transfer member 5 and to suppress the occurrence of thermal stress in the heat transfer member 5.

[0039] As shown in Figs. 7 and 8, the film member 941 is disposed between the lubricant 940 and the heat storage body 4. This can prevent the lubricant 940 and the heat storage body 4 from coming into direct contact with each other. This can also prevent the lubricant 940 from mixing into the heat storage body 4. The film member 941 has a higher thermal conductivity than the heat storage body 4. This can prevent a decrease in the heat transfer between the heat storage body 4 and the heat transfer member 5. This can improve the heat transfer between the heat storage body 4 and the straight pipe section 50, as compared to a case where the heat storage body 4 is disposed in the arrangement space of the film member 941 (see Fig. 10).

[0040] Furthermore, the lubricant 940 is in a powder form and has flowability. Therefore, the lubricant 940 can freely deform as a result of the flow of a large number of particles that make up the lubricant 940. This can improve the lubricity.

[0041] The volume of the storage section 22 shown in FIG. 4 and FIG. 6 is smaller than the volume of the heat storage body 4 after expansion due to the hydration reaction. Therefore, it is possible to suppress the occurrence of dead space in the storage section 22. Furthermore, when the heat storage body 4 expands, it is possible to press the heat storage body 4 against the straight pipe section 50 with the thermal stress suppression member 94. Therefore, it is possible to improve the heat transfer between the heat storage body 4 and the heat transfer member 5. Even when the pressure contact force of the heat storage body 4 against the heat transfer member 5 is high as in the chemical heat storage device 1 of this embodiment, it is possible to assist the thermal deformation of the heat transfer member 5 by the thermal stress suppression member 94 between the heat storage body 4 and the heat transfer surface 500. Therefore, it is possible to suppress the occurrence of thermal stress in the heat transfer member 5.

[0042] As shown in Fig. 4, the direct support member 7 directly supports the heat transfer member (heat transfer member with thermal stress suppression member 94) 5. This makes it difficult for the heat transfer member 5 to deform. The indirect support member 87 supports the inner container 2. This makes it difficult for the inner container 2 to deform. The indirect support member 87 and the direct support member 7 are aligned in the radial direction via the side peripheral wall portion 20. This makes it possible to achieve high positioning accuracy for the heat transfer member 5.

[0043] 4 to 6, the multiple through holes 201 are distributed over the entire side peripheral wall portion 20. This makes it easy to diffuse water vapor throughout the heat storage body 4. In addition, water vapor can be easily collected from the entire heat storage body 4.

[0044] As shown in Figures 1, 2, and 4 to 6, the chemical heat storage device 1 includes an outer container 3. Therefore, the outer surface of the inner container 2 can be used to define the outer flow path 32. That is, the walls (the peripheral side wall 20, the end wall 21) of the inner container 2 can be used to define the storage section 22 on the inside and the outer flow path 32 on the outside. Therefore, the chemical heat storage device 1 is excellent in space saving.

[0045] 3 to 6, a plurality of heat transfer members 5 are arranged in the accommodation portion 22. This makes it possible to increase the surface area of ​​the heat transfer members 5. This makes it possible to improve the heat transfer between the heat medium and the heat storage body 4.

[0046] As shown in FIG. 3, inside the inner container 2 (the storage section 22), a plurality of heat transfer members 5 and a plurality of direct support members 7 are arranged in an intricate manner. Therefore, the shape of the storage section 22 is complex. In this regard, the heat storage body 4 in the initial state is an aggregate (powder) of heat storage material granules. Therefore, when the heat storage body 4 expands from the initial state at the time of the first heat release (during the hydration reaction), the heat storage material granules can be distributed to every corner of the storage section 22 while being appropriately disintegrated (for example, the heat storage material granules can be disintegrated into agglomerates (a combination of a plurality of heat storage material particles) or heat storage material particles) along the shape of the storage section 22. Therefore, even though the shape of the storage section 22 is complex, the occurrence of dead space in the storage section 22 can be suppressed.

[0047] In addition, since the heat storage body 4 expands while being moderately crushed, the expansion pressure can be reduced compared to when the heat storage body 4 is a molded body (a sintered press molded body of heat storage material particles or heat storage material granules. The concept of "heat storage body" in this disclosure includes such molded bodies.) Therefore, it is not necessary to give an excessive pressure-resistant structure (for example, increasing the wall thickness of the wall, reinforcing, changing the material, etc.) to the inner container 2 and each member (heat transfer member 5, direct support member 7) arranged in the storage section 22.

[0048] Second Embodiment The chemical heat storage device of this embodiment differs from the chemical heat storage device of the first embodiment in that the heat storage body is a molded body, the lubricant of the thermal stress suppression member is a molded body, and the thermal stress suppression member does not include a film member. Here, only the differences will be described.

[0049] FIG. 11 shows a partial cross-sectional view in the front-rear direction of the chemical heat storage device of this embodiment. The same reference numerals are used for parts corresponding to those in FIG. 7. The thermal stress suppression member 94 includes a lubricant 940. The lubricant 940 is solid (a graphite compact) and has a cylindrical shape. The lubricant 940 is annularly attached to the heat transfer surface 500. The outer peripheral surface of the lubricant 940 abuts against the heat storage body 4, which is a compact. The rear end of the lubricant 940 abuts against the end wall portion 21. The front end of the lubricant 940 abuts against the heat transfer member mounting plate 81 (see FIG. 5).

[0050] The chemical heat storage device of this embodiment and the chemical heat storage device of the first embodiment have the same action and effect with respect to the common parts of the configuration. The inner and outer circumferential surfaces of the lubricant 940 each have self-lubricating properties. The outer circumferential surface of the lubricant 940 abuts against the inner circumferential surface of the heat storage body 4. Therefore, the sliding resistance between the heat storage body 4 and the lubricant 940 can be reduced. The inner circumferential surface of the lubricant 940 abuts against the heat transfer surface 500. Therefore, the sliding resistance between the heat transfer surface 500 and the heat storage body 4 can be reduced. In this way, according to the thermal stress suppression member 94 of the chemical heat storage device of this embodiment, the sliding resistance can be reduced on both radial sides of the lubricant 940.

[0051] The thermal stress suppression member 94 does not include a film member 941 (see FIG. 7). This allows the structure of the thermal stress suppression member 94 to be simplified. The lubricant 940 is made of a graphite compact. This allows for excellent workability. The inner circumferential surface of the lubricant 940 can be brought into close contact with the entire heat transfer surface 500. In addition, the outer circumferential surface of the lubricant 940 can be brought into close contact with the entire inner circumferential surface of the heat storage body 4. This allows for the heat transfer between the heat storage body 4 and the straight pipe section 50 to be prevented from decreasing.

[0052] <Third embodiment> The chemical heat storage device of this embodiment differs from the chemical heat storage device of the second embodiment in that the thermal stress suppression member protrudes to the rear side of the end wall portion (outside the storage portion). Here, only the difference will be described.

[0053] Fig. 12 shows a partial cross-sectional view in the front-rear direction of the chemical heat storage device of this embodiment. The same reference numerals are used for parts corresponding to those in Fig. 11. The lubricant 940 penetrates the insertion hole 210 and enters the outer flow path 32 from the storage section 22. The outer peripheral surface of the lubricant 940 abuts against the inner peripheral surface of the insertion hole 210.

[0054] The chemical heat storage device of this embodiment and the chemical heat storage device of the second embodiment have similar effects with respect to the common parts. The outer peripheral surface of the lubricant 940 abuts against the inner peripheral surface of the insertion hole 210. Therefore, it is possible to reduce the sliding resistance between the inner peripheral surface of the insertion hole 210, i.e., the end wall portion 21, and the lubricant 940. As in this embodiment, the thermal stress suppression member 94 may protrude from the storage portion 22 to the outside.

[0055] <Other> The embodiment of the chemical heat storage device of the present disclosure has been described above. However, the embodiment is not particularly limited to the above embodiment. It is also possible to implement the present disclosure in various modified and improved forms that can be achieved by those skilled in the art.

[0056] [structure] Among the chemical heat storage devices 1 of the above-mentioned embodiments, the members of the chemical heat storage device 1 of any embodiment can be incorporated into the chemical heat storage device 1 of another embodiment. For example, the thermal stress suppression member 94 shown in Fig. 11 and Fig. 12 may be disposed in the straight pipe section 50 shown in Fig. 7.

[0057] (Inner container 2, outer container 3) The shape of the inner container 2 is not particularly limited. It may be a straight cylinder (I-shaped cylinder), a curved cylinder (C-shaped cylinder, S-shaped cylinder, etc.), or a shape that appropriately combines a straight cylinder portion and a curved cylinder portion (J-shaped cylinder, U-shaped cylinder, etc.). It may be a circular (perfect circle, ellipse, etc.) cylinder, or a polygonal (triangle, square, pentagon, hexagon, etc.) cylinder. The above-mentioned matters regarding the inner container 2 are also applicable to the outer container 3. The shape of the outer container 3 and the shape of the inner container 2 may be the same or different. The number of inner containers 2 arranged relative to the outer container 3 is not particularly limited. The chemical heat storage device 1 does not need to have an outer container 3.

[0058] (Heat transfer member 5, flow path member, direct support member 7, indirect support member 87) The shape of the heat transfer member 5 is not particularly limited. When the heat transfer member 5 is tubular, it may be straight, curved, or a shape that appropriately combines straight and curved pipes. It may be circular or polygonal. The heat transfer member 5 may be a hollow plate that defines a heat medium flow path 52 inside and has an outer surface that abuts against the heat storage body 4. The number of heat transfer members 5 arranged inside the heat storage body 4 is not particularly limited. It may be single or multiple. In addition, the number of passes of the heat transfer member 5 with respect to the inside of the heat storage body 4 is not particularly limited. It may be single or multiple. In addition, the position of the heat transfer member 5 inside the heat storage body 4 is not particularly limited. The heat transfer member 5 may not have the heat medium flow path 52. For example, at least a part of the wall portion (side peripheral wall portion 20, end wall portion 21) of the inner container 2 may be the heat transfer member 5. The above matters regarding the heat transfer member 5 are also applicable to the flow path member described later.

[0059] Instead of the through-hole 201, or together with the through-hole 201, a flow path member may be arranged in the chemical heat storage device 1. A reaction medium flow path through which the reaction medium flows is defined inside the flow path member. One end of the reaction medium flow path opens to the outer flow path 32. The other end of the reaction medium flow path opens to the accommodation section 22 (inside the heat storage body 4). When the flow path member is arranged, the reaction medium can be supplied to the inside of the heat storage body 4 through the reaction medium flow path. In addition, the reaction medium can be recovered from the heat storage body 4 through the reaction medium flow path. The shapes, the number of arrangements, etc. of the direct support member 7 and the indirect support member 87 are not particularly limited.

[0060] (Thermal stress suppression components 94) The shape of the thermal stress suppression member 94 (shape of the straight pipe section 50 in the tube axis A3 direction, shape in the direction perpendicular to the tube axis A3 direction), arrangement, number of arrangements, etc. are not particularly limited. The shape of the thermal stress suppression member 94 may be cylindrical or polygonal tubular. The arrangement of the thermal stress suppression member 94 is sufficient as long as it covers at least a part (preferably the entire surface) of the heat transfer surface 500. The number of arrangements may be multiple thermal stress suppression members 94 on a single heat transfer surface 500. The method of arranging the lubricant 940 on the heat transfer surface 500 is not particularly limited. For example, coating, printing, vapor deposition, adhesion, welding, crimping, bolting, screwing, fitting, etc. may be mentioned. The thermal stress suppression member 94 may be arranged on at least one of the straight pipe section 50 and the curved pipe section 51. For example, the thermal stress suppression member 94 may be arranged only on the straight pipe section 50. The thermal stress suppression member 94 may be arranged only on the curved pipe section 51. Moreover, the thermal stress suppression members 94 may be disposed over the entire heat transfer member 5 (straight pipe portion 50 and curved pipe portion 51).

[0061] A front end portion of the film member 941 (a sealing portion that seals the lubricant 940) may be accommodated in the mounting hole 810 of the heat transfer member mounting plate 81. The front end portion may be fixed to the heat transfer member mounting plate 81. The front end portion may be fixed to the outer circumferential surface of the straight pipe section 50. Examples of a method for fixing the front end portion include adhesion, welding, crimping, bolting, and screwing. The front end portion does not have to be fixed to an adjacent member (the heat transfer member mounting plate 81, the straight pipe section 50, etc.). The same applies to the front end portion of the solid lubricant 940 when the thermal stress suppression member 94 does not include the film member 941.

[0062] Similarly, the rear end of the film member 941 (a sealing portion that seals the lubricant 940) may be accommodated in the insertion hole 210 of the end wall portion 21. The rear end may be fixed to the end wall portion 21. The rear end may be fixed to the outer circumferential surface of the straight pipe portion 50. Examples of a method for fixing the front end include adhesion, welding, crimping, bolting, and screwing. The rear end does not need to be fixed to an adjacent member (the end wall portion 21, the straight pipe portion 50, etc.). The same applies to the rear end of the solid lubricant 940 when the thermal stress suppression member 94 does not include the film member 941.

[0063] [material] There is no particular limitation on the material of each member (inner container 2, outer container 3, heat transfer member 5, direct support member 7, indirect support member 87, reaction medium supply / discharge pipe 80, heat transfer member mounting plate 81, heat medium supply / discharge cylinder 82, partition wall 83, heat medium supply pipe 84, heat medium discharge pipe 85, end plate 86, and thermal stress suppression member 94) constituting the chemical heat storage device 1. Taking into consideration the strength, specific heat, operating temperature, and the like, metal (e.g., stainless steel, aluminum, aluminum alloy, copper, iron, etc.), ceramic, resin, etc. may be used.

[0064] The material of the thermal stress suppression member 94 is not particularly limited. The film member 941 may be a metal such as stainless steel or aluminum. Alternatively, it may be a resin. If the film member 941 is made of metal foil, the film member 941 can be easily deformed. In addition, since the metal foil is thin, the heat transfer between the heat storage body 4 and the straight pipe section 50 can be improved. The state of the lubricant 940 is not particularly limited. It may be a solid (lump or powder), liquid, paste, or the like. Examples of the solid lubricant 940 include graphite, molybdenum disulfide, and boron nitride. Examples of the liquid lubricant 940 include heat transfer oil and a liquid in which graphite is added to oil. Examples of the paste lubricant 940 include heat dissipation grease based on silicone oil, and a paste material to which metal chips, boron, or the like are added.

[0065] The type of chemical heat storage material used for the heat storage material particles of the heat storage body 4 is not particularly limited. For example, it may be a compound (oxide, hydroxide, carbonate, chloride, sulfate, etc.) of an alkaline earth metal (Mg, Ca, Sr, Ba, etc.). The compound may contain one or more alkaline earth metals. Specifically, it may be calcium hydroxide (Ca(OH)2), magnesium hydroxide (Mg(OH)2), barium hydroxide (Ba(OH)2), a composite hydroxide of magnesium and calcium, calcium oxide (CaO), magnesium oxide (MgO), a composite oxide of magnesium and calcium, etc.

[0066] The average primary particle diameter of the heat storage material particles is not particularly limited. For example, it may be 0.1 μm or more and 10 μm or less. The average primary particle diameter is, for example, the median diameter of the particle size distribution (particle size distribution) of the heat storage material particles obtained by a laser diffraction method.

[0067] The type of clay mineral contained in the heat storage body 4 is not particularly limited. For example, it may be sepiolite, attapulgite, kaolinite, bentonite, etc. These clay minerals may be used alone or in combination of two or more kinds. The fiber diameter of the clay mineral is not particularly limited.

[0068] The form of the heat storage material 4 is not particularly limited. It may be in powder form or in lump form. In the case of lump form, it may be a molded body (a sintered press molded body of heat storage material particles or heat storage material granules). The type of reaction medium is not particularly limited. For example, steam (water) or ammonia can be used depending on the type of chemical heat storage material. The type of heat medium is not particularly limited. For example, steam (water), oil (such as silicone oil), air, molten salt, etc. can be used. The reaction medium and heat medium may be gas or liquid. It is sufficient that they have fluidity. [Explanation of symbols]

[0069] 1: chemical heat storage device, 2: inner vessel (reactor), 20: side peripheral wall portion, 201: through hole, 21: end wall portion, 210: insertion hole, 22: storage portion, 220: room, 3: outer vessel, 30: side peripheral wall portion, 31: end wall portion, 310: mounting hole, 32: outer flow path, 4: heat storage body, 5: heat transfer member, 50: straight pipe portion, 500: heat transfer surface, 51: curved pipe portion, 52: heat medium flow path, 7: direct support member, 70: support hole, 80: reaction medium supply and discharge pipe, 8 1: heat transfer member mounting plate, 810: mounting hole, 82: heat medium supply and discharge cylinder, 820: mounting hole, 83: partition wall, 830: supply chamber, 831: discharge chamber, 84: heat medium supply pipe, 85: heat medium discharge pipe, 86: end plate, 87: indirect support member, 870: opening, 88: leg, 94: thermal stress suppression member, 940: lubricant, 941: film member, A1: cylinder shaft, A2: cylinder shaft, A3: tube shaft, R1: reaction medium route, R2: heat medium route

Claims

1. A reactor that defines an accommodation section therein; A heat storage body disposed in the housing portion; A heat transfer member is disposed in the housing portion and has a heat transfer surface for transferring heat to and from the heat storage body; a thermal stress suppression member disposed between the heat storage body and the heat transfer surface and suppressing generation of thermal stress in the heat transfer member; Equipped with The thermal stress suppression member is placed on the heat transfer surface and has a lubricant with a higher thermal conductivity than the heat storage body, and utilizes the lubricating properties of the lubricant to assist in the thermal deformation of the heat transfer member and suppress the occurrence of thermal stress in the heat transfer member.

2. The chemical heat storage device according to claim 1 , wherein the thermal stress suppression member is disposed between the lubricant and the heat storage body, and includes a film member having a thermal conductivity higher than that of the heat storage body.

3. The chemical heat storage device according to claim 1 , wherein the volume of the storage section is smaller than the volume of the heat storage medium after expansion due to a chemical reaction.

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