JP5231076B2 - Chemical heat storage system - Google Patents

Description

  The present invention relates to a chemical heat storage system for storing and releasing heat by a chemical reaction.

In the reactor, a chemical heat storage capsule filled with a chemical heat storage material such as calcium oxide, calcium hydroxide, magnesium oxide, magnesium hydroxide, strontium oxide, strontium hydroxide, barium oxide, barium hydroxide is provided. There is known a heat storage device that radiates heat by reaction and regenerates a chemical heat storage material by heating (for example, see Patent Document 1).
Japanese Patent Publication No. 6-80395

  However, in the conventional techniques as described above, the reaction with carbon dioxide of the chemical heat storage material constituting the heat storage device, that is, carbonation is not considered, and there is room for improvement in this respect.

  In view of the above fact, an object of the present invention is to obtain a chemical heat storage system capable of reducing carbon dioxide that can react with a chemical heat storage material in a closed system.

  The chemical heat storage system according to the first aspect of the present invention includes a reaction part in which a chemical heat storage material that stores heat by generating a dehydration reaction by heating and radiates heat by generating a hydration reaction, and an airtight state in the reaction part A condensing part for condensing water vapor generated by the dehydration reaction from the reaction part, a storage part communicating in an airtight manner with the condensing part, and storing water condensed in the condensing part, An evaporating unit that is communicated in an airtight state with the reaction unit and the storage unit, evaporates water in the storage unit or water supplied from the storage unit, and generates water vapor that is supplied to the reaction unit, and the reaction unit, Carbon dioxide for absorbing carbon dioxide provided in at least a part of the condensing unit, the evaporating unit, the communicating part between the reacting part and the condensing part, the communicating part between the reacting part and the evaporating part, and the storing part With absorbent material

  In the chemical heat storage system according to claim 1, when the reaction part is heated, the chemical heat storage material in the reaction part stores heat by causing a dehydration reaction. The water vapor generated with this dehydration reaction is condensed in the condensing part and stored in the storage part. When dissipating heat to the chemical heat storage material in the reaction part, the water in the storage part is evaporated in the evaporation part, and this water vapor is introduced into the reaction part. Then, the chemical heat storage material in the reactor generates a hydration reaction and dissipates heat. For example, the object to be heated can be heated with this heat.

  Here, in the present chemical heat storage system, the reaction section, the condensation section, the storage section, and the evaporation section are communicated in an airtight state. In other words, the steam or water including the space filled with the chemical heat storage material can move. Since the space (including the portion where water is stored) is a closed system, carbon dioxide is prevented from being mixed into the closed system from the outside. And since the carbon dioxide absorbent is provided in at least a part of the closed system, the carbon dioxide in the closed system is absorbed by the carbon dioxide absorbent. Thereby, it can suppress or prevent that the chemical heat storage material in a reactor produces a carbonation reaction, for example.

  Thus, in the chemical heat storage system according to the first aspect, carbon dioxide that can react with the chemical heat storage material in the closed system can be reduced.

  The chemical heat storage system according to claim 2 is the chemical heat storage system according to claim 1, wherein the reaction unit, the condensing unit, the evaporation unit, a communication part between the reaction unit and the condensing unit, the reaction unit, A carbon dioxide absorbent capable of absorbing carbon dioxide in water vapor was provided as at least a part of the communicating portion with the evaporation section as the carbon dioxide absorbent.

  In the chemical heat storage system according to claim 2, since a carbon dioxide absorbing material capable of absorbing carbon dioxide in water vapor is provided in the movement (circulation) path of water vapor in the closed system, carbon dioxide in the water vapor Can be effectively absorbed (decreased).

  A chemical heat storage system according to a third aspect of the present invention is the chemical heat storage system according to the second aspect, comprising an evaporation / condenser in which the condensing unit, the storage unit, and the evaporation unit are integrally configured, and the evaporation The carbon dioxide absorbent is provided in a water vapor circulation path that connects the condenser and the reactor.

  In the chemical heat storage system according to claim 3, since the carbon dioxide absorbent is provided in the water vapor circulation path that connects the evaporator / condenser and the reaction part, the carbon dioxide in the water vapor is good in the part where the water vapor reciprocates. Can be absorbed into.

  A chemical heat storage system according to a fourth aspect of the invention is the chemical heat storage system according to the second and third aspects, wherein lithium silicate is used as the carbon dioxide absorbent.

  In the chemical heat storage system according to the fourth aspect, the carbon dioxide in the water vapor can be effectively absorbed by the lithium silicate.

  The chemical heat storage system according to claim 5 is the chemical heat storage system according to any one of claims 1 to 4, wherein carbon dioxide in water is used as the carbon dioxide absorbent in the water of the storage section. A carbon dioxide absorbing material capable of absorbing was added.

  In the chemical heat storage system according to claim 5, the carbon dioxide dissolved in the water is effectively absorbed (reduced) by the carbon dioxide absorbent capable of absorbing the carbon dioxide in the water added to the water in the reservoir. Can do. In addition, as carbon dioxide absorbents that can absorb carbon dioxide in water, for example, physical adsorbents (methanol, polyethylene glycol methyl ether, etc.) such as organic amines, alkali salts (aqueous potassium carbonate solution, propylene carbonate, etc.), alcohols, etc. Can be used.

  A chemical heat storage system according to a sixth aspect of the invention is the chemical heat storage system according to the fifth aspect, wherein an organic amine is used as the carbon dioxide absorbent.

  In the chemical heat storage system according to the sixth aspect, carbon dioxide in water can be effectively absorbed by the organic amines. Examples of organic amines that can be used include methyldiethanolamine, diglycolamine, and methylethanolamine.

  The chemical heat storage system according to claim 7 is the chemical heat storage system according to any one of claims 1 to 6, wherein the reaction unit, the condensing unit, the evaporation unit, the reaction unit and the condensing unit. The communicating part between the reaction part and the evaporation part is vacuum degassed.

  In the chemical heat storage system according to the seventh aspect, since the inside of the closed system in which the reaction unit, the condensing unit, the storage unit, and the evaporation unit communicate with each other is vacuum degassed, the amount of carbon dioxide in the system is small. And by providing a carbon dioxide absorber as mentioned above, the inside of a system can be maintained in a state with little carbon dioxide.

  The chemical heat storage system according to an eighth aspect of the present invention is the chemical heat storage system according to any one of the first to seventh aspects, wherein an inorganic compound is used as the heat storage material.

  In the chemical heat storage system according to the eighth aspect, since an inorganic compound is used as the chemical heat storage material, the material stability against heat storage and heat release reaction (hydration and dehydration) is high. For this reason, a stable heat storage effect can be obtained over a long period of time.

  The chemical heat storage system according to the ninth aspect of the present invention is the chemical heat storage system according to the eighth aspect, wherein an alkaline earth metal hydroxide is used as the inorganic compound.

  In the chemical heat storage system according to claim 9, since the alkaline earth metal hydroxide is used as the chemical heat storage material, in other words, a material having a small environmental load is used, and therefore, safety including manufacturing, use, and recycling is ensured. Ensuring is easy.

  As described above, the chemical heat storage system according to the present invention has an excellent effect that carbon dioxide that can react with the chemical heat storage material in the closed system can be reduced.

  The chemical heat storage system 10 which concerns on the 1st Embodiment of this invention is demonstrated based on FIGS. 1-4.

  In FIG. 1, a schematic overall configuration of the chemical heat storage system 10 is shown in a schematic system configuration diagram. As shown in this figure, the chemical heat storage system 10 includes a reactor 16 in which a chemical heat storage material 14 is filled in a container 12. The chemical heat storage material 14 constituting the reactor 16 stores heat (absorbs heat) with dehydration and dissipates heat (heat generation) with hydration (restoration to calcium hydroxide).

In this embodiment, calcium hydroxide (Ca (OH) ₂ ), which is one of alkaline earth metal hydroxides, is employed as the chemical heat storage material. Therefore, in the reactor 16, it is set as the structure which can reversibly repeat heat storage and heat dissipation by the reaction shown below.
Ca (OH) ₂ Ｃａ CaO + H ₂ O

When the heat storage amount and the heat generation amount Q are shown together in this equation,
Ca (OH) ₂ + Q → CaO + H ₂ O
CaO + H ₂ O → Ca (OH) ₂ + Q
It becomes. The heat storage capacity per kg of the chemical heat storage material 14 (Ca (OH) ₂ ) is about 1.86 [MJ / kg-Ca (OH) ₂ ].

  Furthermore, in this embodiment, the reactor 16 includes a heating channel 18 for supplying heat to the chemical heat storage material 14, and a heat radiation channel 20 for transporting heat from the chemical heat storage material 14 to a heating target. Is provided. The heating channel 18 is a heat source (heat medium), the chemical heat storage material 14, and a heat exchange unit, and the heat radiation channel 20 is a heat exchange unit between the heat transport medium and the chemical heat storage material 14. In addition, you may comprise the wall surface of the container 12 as a heat exchange part with at least one of a heat source and a heat transport medium.

  As at least a part of the reactor 16 described above, for example, a heat exchange type heat storage and heat dissipation device 22 as shown in FIG. 2 can be used. The heat exchange type heat storage and heat dissipation device 22 includes a heat exchanger body 24 that forms part of the container 12, and a chemical heat storage material composite molded body 25 provided in the heat exchanger body 24. The heat exchanger body 24 includes a shell (outer wall) 26 and a partition wall 28 as a wall body that divides the inside of the shell 26 into a plurality of spaces.

  As a result, the heat exchanger main body 24 performs heat exchange between the heat storage material accommodating portion 30 in which the chemical heat storage material composite formed body 25 is stored and the chemical heat storage material composite formed body 25. Fluid flow paths 32 through which a fluid as a medium flows are alternately arranged. In this embodiment, the heat storage material accommodating portion 30 and the fluid flow path 32 are each a prismatic space having a flat rectangular opening end. Moreover, in this embodiment, the heat exchanger main body 24 is comprised with metal materials, such as stainless steel and aluminum (an aluminum alloy is included), for example.

  In the chemical heat storage material composite molded body 25, for example, a powder chemical heat storage material 14 is kneaded with a binder (for example, clay mineral) and baked to form a flow path 25A for water vapor to flow inside. It is formed in a substantially rectangular block shape. The chemical heat storage material composite molded body 25 is arranged (inserted) in a state in which the periphery thereof is in close contact with the heat storage material housing portion 30 of the heat exchanger main body 24 to constitute the heat exchange type heat storage and heat dissipation device 22. . For example, the chemical heat storage material composite molded body 25 before firing is inserted into the heat storage material accommodating portion 30 and then fired, so that the periphery of the chemical heat storage material composite molded body 25 adheres well to the inner surface of the heat storage material accommodating portion 30. Can be made.

  By joining a header member (not shown) for communicating the flow paths 25A of the plurality of chemical heat storage material composite molded bodies 25 to the shell 26 of the heat exchange type heat storage and heat dissipation device 22 described above, The reactor 16 in which the chemical heat storage material composite molded body 25 is incorporated can be configured. Further, a part of the plurality of fluid flow paths 32 of the heat exchange type heat storage and heat dissipation device 22 can be used as the heating flow path 18 and the other part can be used as the heat dissipation flow path 20. In this embodiment, the heat exchange type heat storage / heat dissipating device 22, that is, the reactor 16 includes an opening direction of the heat storage material accommodation unit 30 (a flow direction of water vapor) and an opening direction of the fluid flow path 32 (a flow direction of the heat medium and heat transport medium). Are orthogonal to each other when viewed from the side.

  In addition, the chemical heat storage system 10 evaporates the condensing unit that condenses the water vapor introduced from the reactor 16, the storage unit that stores water condensed with water vapor (liquid phase water, the same applies hereinafter), and the stored water. And an evaporator / condenser 34 having both functions as an evaporation section for generating water vapor to be supplied to the reactor 16. The evaporator / condenser 34 is configured such that a water vapor condensing refrigerant channel 38 and an evaporation heat medium channel 40 are provided in a container 36. In this embodiment, the refrigerant flow path 38 is provided so as to perform heat exchange in a portion including at least the gas phase portion 36 </ b> A in the container 36, and the heat medium flow path 40 is at least in the liquid phase portion in the container 36. (Storage part) It is provided so that heat exchange may be performed in the part including 36B.

  The container 36 of the evaporator / condenser 34 is communicated with the container 12 of the reactor 16 through a water vapor circulation path 42 constituting a water vapor circulation system. The water vapor circulation path 42 is provided with an on-off valve 44 for switching between communication and non-communication between the container 36 and the container 12. In this embodiment, the container 12, the container 36, the water vapor circulation path 42, and the on-off valve 44 are hermetically connected to each other, and these internal spaces are evacuated.

The chemical heat storage system 10 includes a CO2 absorption filter 46 for removing carbon dioxide (hereinafter referred to as CO2) in water vapor that moves (circulates) between the reactor 16 and the evaporator / condenser 34. . The CO 2 absorption filter 46 is configured by enclosing lithium silicate (Li ₄ SiO ₄ ), which is one of the lithium composite oxides as the medium carbon dioxide absorbent. In this embodiment, the CO 2 absorption filter 46 is disposed in a filter case 48 that is airtightly provided in the water vapor circulation path 42.

  In the chemical heat storage system 10, organic amines as an underwater carbon dioxide absorbent for removing CO2 in water stored in the liquid phase part 36B of the evaporator / condenser 34 are stored in the liquid phase part 36B. Has been added to the water. In this embodiment, methyldiethanolamine is used as the organic amine. This CO2 absorbent is an organic solvent that is soluble in water and excellent in long-term storage stability and stability. In this embodiment, the liquid phase is an aqueous solution having a concentration of about 30% by mass or less. Part 36B is added (dissolved) in water.

The CO2 absorption reaction of such amines is complicated.
2RNH ₂ + CO ₂ + H ₂ O⇔ (RNH ₃ ) ₂ CO ₃
The CO2 is selectively absorbed by organic amines by reactions such as the above. As described above, the organic amines and CO2 react with each other at a ratio of 1: 1. Therefore, the organic amines are characterized by a large CO2 adsorption capacity.

  Next, the operation of the first embodiment will be described.

  In the chemical heat storage system 10 having the above configuration, when storing heat in the chemical heat storage material 14 (chemical heat storage material composite molded body 25) of the reactor 16, the on-off valve 44 is opened as shown in FIG. In the state, the heating medium from the heat source is circulated through the heating channel 18. Then, the chemical heat storage material 14 undergoes a dehydration reaction due to the heat from the heating flow path 18, and this heat is stored in the chemical heat storage material 14. At this time, the water dehydrated from the chemical heat storage material 14 is introduced into the evaporator / condenser 34 through the water vapor circulation path 42. In the evaporator / condenser 34, the water vapor is cooled by the refrigerant flowing through the refrigerant flow path 38, and the condensed water is stored in the liquid phase portion 36 </ b> B of the container 36.

  On the other hand, when dissipating the heat stored in the reactor 16, as shown in FIG. 3B, the chemical heat storage system 10 opens the on-off valve 44 and opens the heating medium of the evaporator / condenser 34. A heat medium is circulated through the flow path 40. Then, the water in the liquid phase part 36 </ b> B is evaporated by heat exchange with the heat medium in the heat medium flow path 40, and the water vapor is supplied to the chemical heat storage material 14 in the reactor 16 through the water vapor circulation path 42. Thereby, the chemical heat storage material 14 dissipates heat while causing a hydration reaction. This heat is transported to the object to be heated by the heat transport medium flowing through the heat radiating channel 20 and is used for heating the object to be heated.

  The heat storage / radiation of the chemical heat storage material 14 described above will be supplemented with reference to the cycle of the chemical heat storage system 10 shown in FIG. FIG. 4 shows the cycle of the chemical heat storage system 10 at the pressure equilibrium point shown in the PT diagram. In this figure, the upper isobaric line represents a dehydration (endothermic) reaction, and the lower isobaric line represents a hydration (exothermic) reaction.

  As shown in this cycle, when the temperature of the chemical heat storage material is stored at about 424 ° C., the equilibrium temperature of water vapor is about 50 ° C. In the chemical heat storage system 10, the water vapor is cooled to 50 ° C. or less by heat exchange with the refrigerant in the refrigerant flow path 38 in the evaporator / condenser 34 and condensed into water.

  Moreover, in the chemical heat storage system 10, by supplying a heat medium to the heat medium flow path 40, water vapor having a vapor pressure corresponding to the temperature of the heat medium is generated. As shown in FIG. 4, when water vapor is generated at 0 ° C. by the heat medium in the heat medium flow path 40, the equilibrium pressure becomes approximately 0.65 [kPa], and the chemical heat storage material 14 radiates heat at approximately 330 ° C. I understand that. Thus, in the chemical heat storage system 10 in which the inside of the water vapor circulation system is evacuated, heat can be pumped from a low-temperature heat source near 0 ° C. to obtain a high temperature as high as 330 ° C.

  Here, in the chemical heat storage system 10, since the CO2 absorption filter 46 is provided in the water vapor circulation path 42 that communicates the reactor 16 and the evaporator / condenser 34, CO2 present in the water vapor is reduced to the CO2 absorption filter 46 ( Is absorbed (substantially fixed) by lithium silicate enclosed in the water and removed from the water vapor circulation system. Thereby, for example, the CO2 adsorbed on the chemical heat storage material 14 (chemical heat storage material composite molded body 25) before sealing to the container 12 is desorbed from the chemical heat storage material 14 along with vacuum degassing, and the water vapor circulation system. Even if it exists, the CO2 is absorbed by the CO2 absorption filter 46, so that the CO2 in the water vapor circulation system is remarkably reduced.

  Further, in the chemical heat storage system 10, since methyldiethanolamine is added to the water stored in the liquid phase part 36 </ b> B of the container 36 constituting the evaporator / condenser 34, CO2 dissolved in the water is converted into methyldiethanolamine. Absorbed and immobilized.

  Thus, in the chemical heat storage system 10, in the configuration in which the chemical heat storage material 14 and water vapor (water) are sealed in a sealed (vacuum degassing) system, the amount of CO2 in the sealed system can be reduced. For this reason, carbonation of the chemical heat storage material 14 is suppressed.

Supplementing the carbonation of the chemical heat storage material 14, when water vapor and CO 2 coexist in an environment of about 450 ° C. close to the above heat storage temperature, the chemical heat storage material 14 which is a hydroxide (Ca (OH) ₂ ). This promotes the carbonation reaction. CaCO ₃ which is a carbonate of the chemical heat storage material 14 (Ca (OH) ₂ ) is a very stable compound having a decomposition temperature of 950 ° C. and does not contribute to chemical heat storage. For this reason, carbonation of the chemical heat storage material 14 causes a decrease in the heat storage capacity of the reactor 16. Further, it is not practical to completely remove CO2 in the reactor 16 (chemical heat storage material 14) and the evaporator / condenser 34 (water) in advance, which complicates the manufacturing process and increases costs.

  In contrast, the chemical heat storage system 10 according to the present invention is new in that CO 2 can exist in the reactor 16 and the evaporator / condenser 34 even in a closed system, particularly in a vacuum degassed system. Based on this knowledge, the CO2 absorption filter 46 provided in the water vapor circulation path 42 and the methyldiethanolamine dissolved in the water stored in the liquid phase part 36B of the container 36 are used on-site (reactions and phase changes accompanying heat storage and heat dissipation). The amount of CO2 in the closed system is reduced by absorbing CO2 in the closed system).

  Thereby, in the chemical heat storage system 10, since carbonation is suppressed by the chemical heat storage material 14, required heat storage capacity (heat storage capacity per unit mass of the chemical heat storage material 14) can be obtained. In addition, as described above, the CO2 absorption filter 46 is provided, and methyldiethanolamine is added to water, so that the influence on the manufacturing process and cost is small.

  Further, in the chemical heat storage system 10, lithium silicate having a large CO2 absorption capacity is used as the CO2 absorbent in water vapor, so that CO2 in the water vapor circulation system is absorbed and removed with a small amount of lithium silicate (small CO2 absorption filter 46). be able to. In the chemical heat storage system 10, the CO2 absorption filter 46 is provided in the water vapor circulation path 42. In other words, the CO2 absorption filter 46 is disposed at a position away from the high temperature portion where the dehydration reaction of the chemical heat storage material 14 occurs. Therefore, the CO2 absorption filter 46 can be easily provided.

  Furthermore, since the chemical heat storage system 10 uses methyldiethanolamine having a large CO2 absorption capacity, CO2 in water stored in the liquid phase part 36 </ b> B of the container 36 can be effectively absorbed and fixed. In the chemical heat storage system 10, the maximum temperature in the evaporator / condenser 34 is about 50 ° C. as shown in FIGS. 1 and 4, so that the thermal durability of methyldiethanolamine does not become a problem. .

  Furthermore, since the chemical heat storage system 10 uses calcium hydroxide, which is an inorganic compound, as the chemical heat storage material 14, the material stability against heat storage and heat release reaction (hydration and dehydration) is high. In particular, since calcium hydroxide is highly reversible with respect to magnesium hydroxide and the like (having almost 100% hydration and dehydration rate), a stable heat storage effect can be obtained over a long period of time. Further, since calcium hydroxide has low sensitivity to impurities with respect to magnesium hydroxide and the like, this point also contributes to long-term stable operation. In particular, since calcium hydroxide which is an alkaline earth metal compound is used as the chemical heat storage material 14, in other words, by using a material with a small environmental load, the chemical heat storage material 14 (chemical heat storage material composite molded body). It is easy to ensure safety including manufacture, use and recycling of 25).

  Next, another embodiment of the present invention will be described. Note that parts and portions that are basically the same as those in the first embodiment or the previous configuration are denoted by the same reference numerals as those in the first embodiment or the previous configuration, and the description thereof is omitted. May be omitted.

(Second Embodiment)
A chemical heat storage system 50 according to a second embodiment of the present invention will be described with reference to FIG. FIG. 5 shows a schematic overall configuration of the chemical heat storage system 50 in a schematic system configuration diagram. As shown in this figure, the chemical heat storage system 50 is provided with a heat medium flow path 52 as a heating means for heating the CO2 absorption filter 46, and thus the chemical heat storage system 10 according to the first embodiment. Is different.

  In the chemical heat storage system 50, the CO2 absorbed by the lithium silicate by heating the CO2 absorption filter 46 is released to regenerate the lithium silicate. That is, the chemical heat storage system 50 is configured to be able to regenerate lithium silicate by batch processing. Note that lithium silicate causes a CO 2 release reaction at about 900 ° C. or higher.

  Further, the filter case 48 constituting the chemical heat storage system 50 is provided with an on-off valve 56 for connecting a vacuum pump (blower) 54 as an exhaust means for exhausting CO2 released from the CO2 absorption filter 46. Yes. In the chemical heat storage system 50, the open / close valve 56 is closed and connected to the vacuum pump 54, and the heat medium flows through the heat medium flow path 52 while operating the vacuum pump 54, thereby releasing CO 2 from the CO 2 absorption filter 46. Furthermore, it is designed to be discharged out of the closed system. Other configurations of the chemical heat storage system 50 are the same as the corresponding configurations of the chemical heat storage system 10.

  Therefore, also by the chemical heat storage system 50 according to the second embodiment, the same effects as the chemical heat storage system 10 can be obtained basically by the same configuration as the chemical heat storage system 10 according to the first embodiment. . In addition, since the chemical heat storage system 50 includes the heat medium flow path 52 and the on-off valve 56, it is possible to release CO2 absorbed by the CO2 absorption filter 46 by batch processing (regeneration of lithium silicate).

  Therefore, in the chemical heat storage system 50, the CO2 absorption action by the CO2 absorption filter 46 can be maintained semipermanently by performing the regeneration process of lithium silicate in a timely manner. In addition, since the CO2 absorption filter 46 is disposed away from the reactor 16, it is possible to suppress the heat accompanying the regeneration of the lithium silicate from being transmitted to the chemical heat storage material 14, and to cause thermal damage to the chemical heat storage material 14. Giving is prevented. That is, high durability is ensured as the entire chemical heat storage system 50.

  In the second embodiment, the example in which the CO2 absorption filter 46 is heated via the heat medium flow path 52 has been shown. However, the present invention is not limited to this, and for example, the CO2 absorption filter from the outside of the filter case 48. 46 may be heated, or the CO2 absorption filter 46 may be taken out of the filter case 48 to regenerate lithium silicate, and then the CO2 absorption filter 46 may be returned to the filter case 48 and then vacuum degassed again. good. Further, such a CO2 absorption filter 46 may be put in and out of the filter case 48 in a vacuum environment.

(Third embodiment)
A chemical heat storage system 60 according to a third embodiment of the present invention will be described with reference to FIG. FIG. 6 shows a schematic overall system configuration of the chemical heat storage system 60 in a schematic system configuration diagram. As shown in this figure, instead of the evaporator / condenser 34, the chemical heat storage system 60 includes a condenser 62 as a condensing unit configured separately from each other, a water tank 64 as a storage unit, and an evaporating unit. It differs from the chemical heat storage system 10 which concerns on 1st Embodiment by the point provided with the evaporator 66 as.

  The condenser 62 is configured by providing a refrigerant flow path 38 in a container 70 communicated with the container 12 of the reactor 16 via a discharge water vapor line 68. The discharge water vapor line 68 is provided with an open / close valve 72. The bottom of the container 70 of the condenser 62 is communicated with the water tank 64 via a condensed water recovery line 74.

  The evaporator 66 is configured by providing the heat medium flow path 40 in a container 78 communicated with the container 12 of the reactor 16 through a supply steam line 76. The supply steam line 76 is provided with an on-off valve 80. A container 78 of the evaporator 66 is communicated with the water tank 64 through a water supply line 82. Further, the water supply line 82 is provided with a water pump 84 for pumping water stored in the water tank 64 to the container 78 of the evaporator 66.

  Further, the chemical heat storage system 60 includes open / close valves 86 and 88 provided at a connection portion between the condensed water recovery line 74 and the water tank 64 and a connection portion between the water supply line 82 and the water tank 64. In this embodiment, the connecting portion between the condensed water recovery line 74 and the water tank 64 and the connecting portion between the water supply line 82 and the water tank 64 are lower than the design minimum liquid level in the water tank 64 in the gravity direction. Is set to The water tank 64 may be integrated with either the container 70 of the condenser 62 or the container 78 of the evaporator 66.

  In the chemical heat storage system 60, the CO 2 absorption filter 46 is provided in the filter case 48 provided in the discharge water vapor line 68. On the other hand, methyldiethanolamine is added (dissolved) to the water stored in the water tank 64. Other configurations of the chemical heat storage system 60 are the same as the corresponding configurations of the chemical heat storage system 10.

  Next, the operation of the third embodiment will be described.

  In the chemical heat storage system 60 having the above-described configuration, when storing heat in the chemical heat storage material 14 (chemical heat storage material composite molded body 25) of the reactor 16, the on-off valves 80 and 88 are closed and the on-off valves 72 and 86 are opened. In this state, the heat medium from the heat source is circulated through the heating channel 18. Then, the chemical heat storage material 14 undergoes a dehydration reaction due to the heat from the heating flow path 18, and this heat is stored in the chemical heat storage material 14. At this time, water vapor dehydrated from the chemical heat storage material 14 is introduced into the condenser 62 via the discharge water vapor line 68. In the condenser 62, the water vapor is cooled by the refrigerant flowing through the refrigerant flow path 38, and the condensed water is stored in the water tank 64.

  On the other hand, when dissipating the heat stored in the reactor 16, the chemical heat storage system 10 opens the on-off valves 80, 88 and closes the on-off valves 72, 86, and the heat transfer flow of the evaporator 66. A heat medium is circulated through the passage 40 and the water pump 84 is operated. Then, water is replenished into the container 78 by the water pump 84 and the water is evaporated by heat exchange with the heat medium in the heat medium flow path 40, and this water vapor is supplied into the reactor 16 via the supply water vapor line 76. Supplied to the chemical heat storage material 14. Thereby, the chemical heat storage material 14 dissipates heat while causing a hydration reaction. This heat is transported to the object to be heated by the heat transport medium flowing through the heat radiating channel 20 and is used for heating the object to be heated.

  Thus, the chemical heat storage system 60 according to the second embodiment basically functions in the same manner as the chemical heat storage system 10 according to the first embodiment. In other words, the chemical heat storage system 60 is configured by dividing the three functions (condensation, storage, and evaporation) of the evaporator / condenser 34 into a condenser 62, a water tank 64, and an evaporator 66. The same effect can be acquired by the same operation as that of the chemical heat storage system 10 according to the embodiment. Further, in the chemical heat storage system 60, the connecting portion between the condensed water recovery line 74 and the water tank 64 and the connecting portion between the water supply line 82 and the water tank 64 are lower than the lowest liquid level in the water tank 64 in the direction of gravity. In other words, since the water pressure of the water in the water tank 64 acts on these connection portions, the entry of outside air from these connection portions is effectively suppressed.

  In each of the above-described embodiments, the CO2 absorption filter 46 is provided in the water vapor circulation path 42 and the discharge water vapor line 68. However, the present invention is not limited to this, for example, the CO2 absorption filter 46 having the above arrangement. Instead of or together with the CO2 absorption filter 46 arranged as described above, the CO2 absorption filter 46 may be provided in the container 12 or the container 36 in the first to third embodiments. In the third embodiment, the supply water vapor line 76 is provided. A CO2 absorption filter 46 may be provided.

  In each of the above-described embodiments, an example in which lithium silicate that is a lithium composite oxide is used as an absorbent that absorbs CO2 in water vapor has been described. However, the present invention is not limited to this, and for example, other dioxide dioxide. A carbon adsorbent may be used.

  Further, in each of the above-described embodiments, an example in which methyldiethanolamine, which is an organic amine, is used as an absorbent that absorbs CO2 in water has been shown. However, the present invention is not limited thereto, and examples thereof include diglycolamine, methyl Other organic amines such as ethanolamine, carbon dioxide adsorbents other than organic amines such as alkali salts (potassium carbonate aqueous solution, propylene carbonate, etc.), physical adsorbents such as alcohol (methanol, polyethylene glycol methyl ether, etc.) May be.

  Furthermore, in each of the above-described embodiments, an example in which calcium hydroxide is used as a chemical heat storage material has been shown. However, the present invention is not limited to this, and various chemical heat storages that perform various heat dissipation and heat storage by hydration / dehydration. It can be implemented using materials.

  Moreover, in each above-mentioned embodiment, although the chemical heat storage material 14 WHEREIN: Although the chemical heat storage material composite molded body 25 in which the flow path 25A was formed by shape | molding a powder chemical heat storage material was shown, this book The invention is not limited to this. For example, the reactor 16 may be configured by filling the container 12 with the chemical heat storage material 14 formed in a granular shape.

It is a system configuration figure showing typically the outline whole composition of the chemical heat storage system concerning a 1st embodiment of the present invention. It is a perspective view which shows typically a part of reactor which comprises the chemical thermal storage system which concerns on the 1st Embodiment of this invention. It is a figure for demonstrating the operation mode of the chemical heat storage system which concerns on the 1st Embodiment of this invention, Comprising: (A) is a system block diagram of heat storage mode, (B) is a system block diagram of heat dissipation mode. . It is a diagram which shows the relationship between the absorbed quantity of the absorber which comprises the chemical thermal storage system which concerns on the 1st Embodiment of this invention, and an equilibrium pressure. It is a system block diagram which shows typically the general | schematic whole structure of the chemical heat storage system which concerns on the 2nd Embodiment of this invention. It is a system block diagram which shows typically the general | schematic whole structure of the chemical heat storage system which concerns on the 3rd Embodiment of this invention.

Explanation of symbols

10 Chemical Thermal Storage System 14 Chemical Thermal Storage Material 16 Reactor 25 Chemical Thermal Storage Material Composite Form (Chemical Thermal Storage Material)
34 Evaporator / Condenser (Condenser, Storage, Evaporator)
46 CO2 absorption filter (carbon dioxide absorbent, lithium silicate)
50/60 Chemical heat storage system 62 Condenser (condenser)
64 Water tank (storage part)
66 Evaporator (evaporator)

Claims (9)

Reacting part with a built-in chemical heat storage material that stores heat by generating a dehydration reaction by heating and dissipates heat by generating a hydration reaction;
A condensing unit that is communicated in an airtight state with the reaction unit, and that condenses water vapor generated in the dehydration reaction from the reaction unit;
A reservoir that communicates with the condensing unit in an airtight state and stores water condensed in the condensing unit;
An evaporating unit that communicates in an airtight state with the reaction unit and the storage unit, and generates water vapor that evaporates the water in the storage unit or the water supplied from the storage unit and supplies the water to the reaction unit;
Provided in at least part of the reaction part, the condensation part, the evaporation part, the communication part between the reaction part and the condensation part, the communication part between the reaction part and the evaporation part, and the storage part, and absorbs carbon dioxide Carbon dioxide absorber for
Including chemical heat storage system.   At least part of the reaction part, the condensation part, the evaporation part, the communication part between the reaction part and the condensation part, and the communication part between the reaction part and the evaporation part are used as the carbon dioxide absorbent as the carbon dioxide absorbent. The chemical heat storage system according to claim 1, further comprising a carbon dioxide absorbent capable of absorbing carbon. An evaporator / condenser in which the condensing unit, the storage unit, and the evaporation unit are configured integrally;
The chemical heat storage system of Claim 2 which provided the said carbon dioxide absorber in the water vapor circuit which connects the said evaporator / condenser and the said reactor.   The chemical heat storage system according to claim 2 or 3, wherein lithium silicate is used as the carbon dioxide absorbent.   The chemical heat storage system according to any one of claims 1 to 4, wherein a carbon dioxide absorbent capable of absorbing carbon dioxide in water is added as the carbon dioxide absorbent in the water of the reservoir.   The chemical heat storage system according to claim 5, wherein an organic amine is used as the carbon dioxide absorbent.   The reaction part, the condensation part, the evaporation part, the communication part between the reaction part and the condensation part, and the communication part between the reaction part and the evaporation part are vacuum degassed. The chemical heat storage system according to claim 1.   The chemical heat storage system according to any one of claims 1 to 7, wherein an inorganic compound is used as the heat storage material.   The chemical heat storage system according to claim 8, wherein an alkaline earth metal hydroxide is used as the inorganic compound.

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