Chemical heat pump

Abstract

To realize a chemical heat pump that can suppress the reduction in the reaction rate of endothermic reactions. [Solution] The chemical heat pump (1) comprises an endothermic reaction device (10) that generates decomposition components from raw material components, a first separation device (20A) and a second separation device (20B) that separate the raw material components or decomposition components, and an exothermic reaction device (30) that generates raw material components from the decomposition components, and is configured so that the raw material components generated in the exothermic reaction device (30) and the raw material components separated in the second separation device (20B) are supplied to the endothermic reaction device (10).

Description

[Technical Field]

[0001] This invention relates to a chemical heat pump. [Background technology]

[0002] Against the backdrop of global warming and other factors, interest in energy-saving technologies remains high, and there is a demand for technologies that effectively utilize thermal energy by storing or releasing excess waste heat. One such technology is a chemical heat pump, in which isopropyl alcohol is decomposed into acetone and hydrogen by an endothermic reaction in the presence of a catalyst at the bottom of a distillation column, the decomposed acetone and hydrogen are distilled out of the distillation column and introduced into a heat exchange reactor, isopropyl alcohol is produced from the acetone and hydrogen by an exothermic reaction in the presence of a catalyst, and the produced isopropyl alcohol is returned to the bottom of the distillation column (see, for example, Patent Document 1). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 03-263550 [Overview of the project] [Problems that the invention aims to solve]

[0004] In the chemical heat pump described above, if acetone, a product of the endothermic reaction, is present in the bottom liquid, the reaction rate of the endothermic reaction tends to decrease due to the acetone. When the reaction rate of the endothermic reaction decreases, it becomes necessary to enlarge the reactor for the endothermic reaction (distillation column in the prior art described above) and to suppress this decrease in the reaction rate, and more catalyst is required. Furthermore, the lower the reaction rate of the endothermic reaction, the lower the acetone yield in that endothermic reaction, and the lower the acetone yield, the lower the overall thermal efficiency of the chemical heat pump. Thus, there is still room for improvement in the conventional technology from the perspective of suppressing the reduction in the reaction rate of the endothermic reaction.

[0005] One aspect of the present invention aims to realize a chemical heat pump capable of suppressing the reduction in the reaction rate of an endothermic reaction. [Means for solving the problem]

[0006] To solve the above problems, the present invention has the following embodiments.

[0007] [1] A chemical heat pump comprising: an endothermic reactor for supplying first thermal energy and decomposing raw material components into their decomposed components by an endothermic reaction in the presence of a first catalyst; a first separation device for separating the decomposed components from the raw material components and decomposed components discharged from the endothermic reactor; a second separation device for separating the raw material components from the raw material components and decomposed components discharged from the first separation device; and an exothermic reactor for supplying the decomposed components discharged from the first separation device and generating the raw material components from the decomposed components by an exothermic reaction in the presence of a second catalyst, and outputting second thermal energy higher than the first thermal energy, wherein the raw material components generated in the exothermic reactor and the raw material components separated in the second separation device are supplied to the endothermic reactor.

[0008] [2] The chemical heat pump according to [1], wherein the raw material component is isopropyl alcohol and the decomposition component is acetone and hydrogen.

[0009] [3] The chemical heat pump according to [1] or [2], wherein the second separation apparatus includes a distillation column for distilling off the decomposition components from the raw material components and decomposition components discharged from the endothermic reaction apparatus, a condenser for cooling the components distilled off from the distillation column, and a reflux tank for containing the liquid components generated in the condenser, wherein the gaseous components discharged from the condenser are supplied to the exothermic reaction apparatus, and the raw material components contained in the reflux tank are supplied to the distillation column.

[0010] (4) The chemical heat pump according to (3), wherein the second separation device further comprises a circulation flow path for circulating a part of the bottom liquid of the distillation column, and a reboiler for heating the liquid in the circulation flow path, and the first heat energy is supplied to the reboiler as heat energy for heating the liquid.

[0011] (5) The chemical heat pump according to any one of (1) to (4), wherein the first catalyst is a granular catalyst, and the endothermic reaction device comprises a fixed bed constituted by the granular catalyst in the flow path for the raw material components.

[0012] (6) The chemical heat pump according to (5), wherein the granular catalyst is one or both of a carbon-supported ruthenium catalyst comprising activated carbon particles and ruthenium supported thereon, and sponge nickel.

[0013] (7) The chemical heat pump according to (2), wherein the concentration of acetone in the liquid supplied from the second separation device to the endothermic reaction device is 4% by mass or less. Effects of the Invention

[0014] According to one aspect of the present invention, a chemical heat pump capable of suppressing a reduction in the reaction rate of an endothermic reaction can be implemented. Brief Description of the Drawings

[0015] [Figure 1] It is a diagram schematically showing an example of the configuration of a chemical heat pump according to an embodiment of the present invention. [Figure 2] It is a diagram schematically showing an example of the configuration of a chemical heat pump according to a comparative embodiment of the present invention. Modes for Carrying Out the Invention

[0016] As a chemical heat pump according to an embodiment of the present invention, a chemical heat pump using an isopropyl alcohol, acetone, hydrogen reaction system (also referred to as "isopropyl alcohol / acetone, hydrogen reaction system") will be described. In the present embodiment, the raw material component is isopropyl alcohol, and the decomposition components are acetone and hydrogen.

[0017] [Configuration of Apparatus] As shown in FIG. 1, the chemical heat pump 1 includes an endothermic reaction device 10, a first separation device 20A, a second separation device 20B, and an exothermic reaction device 30.

[0018] The endothermic reaction device 10 receives external first thermal energy Q L1 that is supplied thereto, and is a device for decomposing isopropyl alcohol into acetone and hydrogen by an endothermic reaction in the presence of a first catalyst.

[0019] In the present embodiment, the endothermic reaction device 10 is an endothermic reactor. The endothermic reactor has a shell and a plurality of tubes penetrating the inside and outside of the shell. The interior of the shell is a flow path for a heat medium, and the tubes are flow paths for the raw material component and the decomposition components thereof.

[0020] The first thermal energy Q is supplied to the endothermic reaction device 10 L1 . For example, the first thermal energy Q L1 only needs to be thermal energy capable of realizing the endothermic reaction in the endothermic reaction device 10, and may be, for example, waste heat from external equipment. Regarding the waste heat from external equipment, the medium itself containing waste heat such as exhaust gas from external equipment may be supplied as the heat medium to the endothermic reaction device 10, or it may be supplied to the endothermic reaction device 10 via a heat medium circulating between the waste heat part of the external equipment and the endothermic reaction device 10. The first thermal energy Q L1 having heat medium is supplied to the aforementioned shell and discharged from the shell, whereby the first thermal energy Q L1 is supplied to the endothermic reaction device 10.

[0021] Furthermore, in this embodiment, the first catalyst is a granular catalyst. The endothermic reactor 10 includes a fixed bed composed of the granular catalyst in the flow path of the raw material components (inside the tube mentioned above). The granular catalyst is a particulate catalyst having a particle size on the order of millimeters (e.g., 3-7 mm) in volume-based median diameter.

[0022] In this embodiment, the first catalyst is supplied with the first thermal energy Q during the endothermic reaction. L1 The catalyst can be appropriately selected within a range that allows for the generation of decomposition components from the raw material components. Furthermore, the first catalyst can be appropriately selected depending on the raw material components and their decomposition components. For example, in this embodiment (where the raw material component is isopropyl alcohol and the decomposition components are acetone and hydrogen), the first catalyst is preferably a catalyst containing nickel or ruthenium from the viewpoint of activity.

[0023] Examples of first catalysts containing nickel include sponge nickel. The first catalyst being sponge nickel is preferable from the viewpoint of activity.

[0024] Examples of first catalysts containing ruthenium include carbon-supported ruthenium catalysts. In this embodiment, the "carbon-supported ruthenium catalyst" is a catalyst containing activated carbon particles and ruthenium supported thereon. Ruthenium is lighter than nickel and has higher catalytic activity than nickel, making it preferable from the viewpoint of achieving high yields with small amounts in endothermic reactions.

[0025] The first separation device 20A is a device for separating the decomposed components from the raw material components and decomposed components discharged from the endothermic reaction device 10.

[0026] In this embodiment, the first separation device 20A is a distillation column. The components discharged from the endothermic reactor 10 are a liquid fluid containing acetone and hydrogen produced by the decomposition of isopropyl alcohol, and unreacted isopropyl alcohol. The distillation column only needs to have the capacity to distill off the decomposed components, and may be, for example, a tray column or a packed column. The packing material of the packed column may be ordered packing material or irregular packing material.

[0027] A pipe 13 extending to the bottom of the first separation unit 20A is connected to the outlet of the endothermic reactor 10. A pipe 23A extending to the inlet of the exothermic reactor 30, which will be described later, is connected to the top of the first separation unit 20A via the first condenser 21A. A pipe 24A extending to the first separation unit 20A is connected to the first condenser 21A via the first reflux tank 22A. The first reflux tank 22A is configured to contain the liquid components generated in the first condenser 21A.

[0028] The piping 23A contains the first blower 25A and the heat exchanger 27. The heat exchanger 27 is, for example, a plate heat exchanger having two flow paths that share a plate. One flow path in the heat exchanger 27 is included in the piping 23A leading to the exothermic reaction device 30, and the other flow path is included in the piping 31, which will be described later. The piping 31 is connected to the outlet of the exothermic reaction device 30.

[0029] A pipe 26A, which extends to the second separation unit 20B (described later), is connected to the bottom of the first separation unit 20A.

[0030] The second separation unit 20B is a device for separating the raw material components from the raw material components and decomposed components discharged from the first separation unit 20A.

[0031] In this embodiment, the second separation unit 20B is a distillation column. The components discharged from the first separation unit 20A are mainly a liquid fluid containing acetone produced by the decomposition of isopropyl alcohol and unreacted isopropyl alcohol. The distillation column only needs to have the capacity to distill off the decomposition component, acetone, and may be, for example, a tray column or a packed column. The packing material of the packed column may be ordered packing material or irregular packing material.

[0032] The second separation unit 20B is connected to piping 26A that extends from the bottom of the first separation unit 20A.

[0033] Furthermore, a pipe 23B extending to the second reflux tank 22B via a second condenser 21B is connected to the top of the second separation unit 20B. The second reflux tank 22B is configured to contain the liquid component generated in the second condenser 21B. A pipe 24B extending into the interior of the second separation unit 20B is connected to the bottom of the second reflux tank 22B for returning the liquid component to the second separation unit 20B. Thus, the second separation unit 20B further includes a second condenser 21B for cooling the component distilled from the second separation unit 20B, and a second reflux tank 22B for containing the liquid component generated in the second condenser 21B.

[0034] A pipe 26B is connected to the upper part of the second reflux tank 22B, extending from the second reflux tank 22B and joining the pipe 23A between the first condenser 21A and the first blower 25A via the second blower 25B.

[0035] A pipe 11 extending to the endothermic reactor 10 is connected to the bottom of the second separation unit 20B via a pump 12. A pipe 28B branches off from pipe 11, and pipe 28B is connected to the bottom of the second separation unit 20B via a reboiler 29B. Thus, the second separation unit 20B further includes a circulation channel (pipes 11 and 28B) for circulating a portion of the bottom liquid of the second separation unit 20B, and a reboiler 29B for heating the liquid in the said circulation channel.

[0036] The reboiler 29B is configured to be supplied with third thermal energy Q L2 . The third thermal energy Q L2 may be any thermal energy capable of heating the bottom liquid of the second separation device 20B and distilling off acetone from the bottom liquid. The third thermal energy Q L2 may be the first thermal energy Q L1 , may be waste heat from another external facility that is similar to the first thermal energy Q L1 , or may be a part of the second thermal energy Q described below H .

[0037] The exothermic reaction device 30 is supplied with the decomposed component discharged from the first separation device 20A, generates the aforementioned raw material component from the decomposed component through an exothermic reaction in the presence of a second catalyst, and generates second thermal energy Q that is higher than the first thermal energy Q L1 second thermal energy Q higher than the first thermal energy Q H . The exothermic reaction device 30 is, for example, a multi-tubular reactor. The shell of the multi-tubular reactor serves as a flow path for a heat medium. The tubes have a fixed bed filled with, for example, a particulate second catalyst, and serve as a flow path for the decomposed component.

[0038] The second catalyst is a catalyst that generates the raw material component (isopropyl alcohol) before decomposition from the decomposed components (acetone and hydrogen) through an exothermic reaction. Further, the second catalyst also generates second thermal energy Q that is higher than the first thermal energy Q (waste heat from an external facility) L1 higher than the first thermal energy Q (waste heat from external facilities) second thermal energy Q H together with the reaction. The second catalyst can be appropriately determined within a range that satisfies these conditions. In the present embodiment, it may be a granular catalyst of sponge metal.

[0039] A pipe 31 extending to the first separation device 20A via a heat exchanger 27 is connected to the outlet of the exothermic reaction device 30. The pipe 31 is a pipe for supplying the component produced in the exothermic reaction device 30 to the first separation device 20A, and extends from the exothermic reaction device 30 to the inside of the first separation device 20A.

[0040] As described above, the outlet of the exothermic reaction device 30 is connected to the first separation device 20A by piping 31, the first separation device 20A is connected to the second separation device 20B as previously mentioned, and the second separation device 20B is connected to the inlet of the endothermic reaction device 10 by piping as previously mentioned. In this way, this embodiment is configured so that the raw material components generated in the exothermic reaction device 30 and the raw material components separated in the second separation device 20B are supplied to the endothermic reaction device 10.

[0041] [Explanation of operating status] First, the tubes of the endothermic reactor 10 are filled with 5% Ru / C granular catalyst to form a fixed bed. 5% Ru / C is a catalyst in which ruthenium is supported on activated carbon particles, containing 5% by mass of ruthenium per unit of carbon mass. The tubes of the exothermic reactor 30 are filled with sponge nickel granular catalyst to form a fixed bed. Furthermore, isopropyl alcohol is contained at the bottom of the second separation unit 20B. In addition, a heat transfer medium heated by waste heat from external equipment is circulated and supplied to the endothermic reactor 10, generating the first thermal energy Q. L1 This is supplied to the endothermic reactor 10. Examples of waste heat from external equipment include exhaust heat from an incinerator, waste hot water from a boiler, and waste heat from the top of a distillation equipment column.

[0042] First, pump 12 is activated, and isopropyl alcohol in the second separation unit 20B is supplied to the endothermic reaction unit 10.

[0043] Liquid isopropyl alcohol is continuously supplied to the endothermic reactor 10 and heated to, for example, 70-80°C by the heat transfer medium in the tube (fixed bed of the catalyst). As a result, a portion of the isopropyl alcohol is decomposed into acetone and hydrogen. The fluid after the decomposition reaction, containing isopropyl alcohol, acetone, and hydrogen, is supplied to the first separation device 20A via piping 13.

[0044] The fluid supplied to the first separation unit 20A is heated in the endothermic reactor 10, and the acetone and hydrogen in the fluid are distilled from the top of the first separation unit 20A (distillation column). The distilled gas is sent to the first condenser 21A, and the isopropyl alcohol distilled along with the gas is cooled and liquefied, then contained in the first reflux tank 22A and returned to the first separation unit 20A through piping 24A. The acetone and hydrogen in the gas distilled from the first separation unit 20A are sent from the first condenser 21A through piping 23A to the heat exchanger 27 by the first blower 25A.

[0045] In the heat exchanger 27, acetone and hydrogen exchange heat with the product gases of the exothermic reaction described later, are heated, and then supplied to the exothermic reaction apparatus 30.

[0046] In the exothermic reaction apparatus 30, a heat transfer medium is circulated, and a portion of the acetone and hydrogen supplied to the exothermic reaction apparatus 30 reacts with the second catalyst in the exothermic reaction apparatus 30, generating heat and producing isopropyl alcohol. The heat generated in this reaction is absorbed by the heat transfer medium circulating in the exothermic reaction apparatus 30. As a result, the temperature of the heat transfer medium is heated to, for example, 150-200°C.

[0047] The isopropyl alcohol produced in the exothermic reaction unit 30 is discharged from the exothermic reaction unit 30 along with unreacted acetone and hydrogen, and supplied to the heat exchanger 27 through the piping 31. The gas after the exothermic reaction supplied to the heat exchanger 27 exchanges heat with the aforementioned gaseous components that were supplied to the exothermic reaction unit 30, heating and cooling the gaseous components. The isopropyl alcohol produced in the exothermic reaction unit 30, along with unreacted acetone and hydrogen, is then supplied to the first separation unit 20A.

[0048] The isopropyl alcohol supplied from the exothermic reaction device 30 to the first separation device 20A comes into contact with the gaseous component from the endothermic reaction device 10, absorbs the isopropyl alcohol associated with the gaseous component, flows down the first separation device 20A, and is supplied to the second separation device 20B through the piping 26A.

[0049] Meanwhile, a portion of the bottom liquid from the second separation unit 20B is heated in the reboiler 29B through piping 11 and piping 28B and returned to the second separation unit 20B. In this way, the second separation unit 20B is heated so that acetone, associated with isopropyl alcohol, distills from the top of the column of the first separation unit 20A.

[0050] The isopropyl alcohol associated with the gaseous component supplied to the second separation unit 20B is heated in the second separation unit 20B, and the gaseous component distills out from the top of the column in the second separation unit 20B, while the isopropyl alcohol flows down to the bottom of the column. The gaseous component distilled out from the top of the column is cooled in the second condenser 21B through piping 23B. The isopropyl alcohol distilled out with the gaseous component is liquefied in the second condenser 21B, contained in the second reflux tank 22B, and returned to the second separation unit 20B through piping 24B.

[0051] The gaseous component cooled in the second condenser 21B is mainly acetone. This gaseous component is sent from the second condenser 21B through the second reflux tank 22B, through piping 26B, and to piping 23A by the second blower 25B, where it becomes a raw material component for the exothermic reaction device 30.

[0052] As mentioned above, a portion of the bottom liquid from the second separation unit 20B is heated by piping 28B and reboiler 29B and supplied to the second separation unit 20B, while the remainder is sent to the endothermic reactor 10 via pump 12. There, it is subjected to the aforementioned endothermic reaction to produce acetone and hydrogen, which are supplied to the first separation unit 20A. Piping 26A, the second separation unit 20B, piping 11, pump 12, endothermic reactor 10, and piping 13 constitute the circulation path for the bottom liquid of the first separation unit 20A, and the endothermic reactor 10 also serves as the reboiler for the first separation unit 20A. In this way, the generation of decomposition components (acetone and hydrogen) from the raw material component (isopropyl alcohol) by the endothermic reactor 10, the separation of the decomposition components in the first separation unit 20A, the generation of the raw material component from the decomposition components by the exothermic reactor 30, and the purification of the raw material component (isopropyl alcohol) by the second separation unit 20B are carried out in a continuous manner.

[0053] As described above, the chemical heat pump 1 supplies the first thermal energy Q to the endothermic reactor 10. L1 The supply of [the substance] allows for the continuous production of acetone and hydrogen through the endothermic decomposition reaction of isopropyl alcohol, followed by the production of isopropyl alcohol through the exothermic reaction of these decomposition components. As a result, the first thermal energy Q is generated. L1 The second thermal energy Q has higher thermal energy than the first thermal energy. H These are generated in succession.

[0054] In this embodiment, the operating conditions of the second separation unit 20B can be appropriately determined from the viewpoint of the separation efficiency of acetone from isopropyl alcohol supplied to the endothermic reactor 10 and the balance between the operation of the endothermic and exothermic reactions in the chemical heat pump 1. For example, if the separation efficiency of acetone in the second separation unit 20B is too low, the production rate of acetone and hydrogen from isopropyl alcohol in the endothermic reactor 10 will be insufficient, resulting in an exothermic reaction in the exothermic reactor 30 and the second thermal energy Q generated therefrom. H The concentration of acetone decreases, which can lead to insufficient heat generation efficiency of the chemical heat pump 1. From this viewpoint, the concentration of acetone in the liquid supplied from the second separation unit 20B to the endothermic reaction unit 10 is preferably 5% by mass or less, more preferably 4% by mass or less, and even more preferably 3% by mass or less. From the viewpoint of efficiency of the endothermic reaction, a lower concentration of acetone is better, but it is difficult to completely separate and remove acetone, and this may lead to an increase in the size or cost of the second separation unit 20B. From the viewpoint of avoiding these issues, the concentration of acetone may be, for example, 1% by mass or more. The concentration of acetone affects the separation performance of the second separation unit 20, or the third thermal energy Q. L2 It can be adjusted by the amount of heat.

[0055] [Main effects and benefits] The chemical heat pump 1 comprises an endothermic reactor 10, a first separation unit 20A, a second separation unit 20B, and an exothermic reactor 30. The raw material components generated in the exothermic reactor 30 and the raw material components separated in the second separation unit 20B are supplied to the endothermic reactor 10. Therefore, the decrease in the concentration of raw material components in the liquid supplied from the second separation unit 20B to the endothermic reactor 10 is suppressed. As a result, even when a granular catalyst is used, it is possible to suppress the decrease in the overall thermal efficiency of the chemical heat pump 1 over time. In this way, in the chemical heat pump 1, increasing the concentration of raw material components supplied to the endothermic reactor 10 increases the reaction rate by the first catalyst (granular catalyst), improving the yield of acetone at the outlet of the endothermic reactor 10, and consequently increasing the overall thermal efficiency of the chemical heat pump 1 system.

[0056] Chemical heat pump 1 is particularly suitable for chemically reversible endothermic and exothermic reactions using isopropyl alcohol as the raw material component and acetone and hydrogen as the decomposition components. In this case, a granular catalyst containing nickel or ruthenium is suitable as the first catalyst, with sponge nickel or carbon-supported ruthenium catalyst being more suitable, and carbon-supported ruthenium catalyst being even more suitable. Furthermore, in the endothermic reaction apparatus 10, since a fixed bed composed of granular catalyst can be placed in the flow path of the raw material components, it is suitable for preventing an increase in pressure loss due to clogging of the first catalyst.

[0057] Furthermore, the second separation unit 20B further includes a second condenser and a second reflux tank, and is configured such that the decomposed components distilled from the second separation unit 20B are supplied to the exothermic reaction unit 30, and the raw material components accompanying the decomposed components are returned to the second separation unit 20B. Therefore, in this embodiment, it is possible to further increase the proportion of decomposed components subjected to the exothermic reaction, and the amount of decomposed components returned to the second separation unit 20B is further reduced, thereby further reducing the separation load on the second separation unit 20B. It is also preferable from the viewpoint of sufficiently lowering the concentration of acetone in the bottom liquid of the second separation unit 20B, for example, it is possible to reduce the concentration of acetone in the bottom liquid to 4% by mass or less.

[0058] Furthermore, since the second separation unit 20B further includes a circulation channel for the bottom liquid and a reboiler 29B, it is possible to utilize the first external thermal energy for heating the liquid in the reboiler 29B. Such a configuration is more preferable from the viewpoint of effective utilization of waste heat.

[0059] Furthermore, in the chemical heat pump 1, both the first and second catalysts are positioned as fixed beds within the flow rate of the reactor. Therefore, mainly liquid flows within the chemical heat pump 1, and solids such as powders do not. Thus, it is possible to supply (e.g., by showering) the liquid supplied to the first separation unit 20A and the second separation unit 20B, or the liquid returned to the unit, in such a way that it comes into good contact with the gaseous components within the unit. This is preferable from the viewpoint of improving gas-liquid contact within the unit and enhancing the recovery of raw material components.

[0060] [Calculation example] The thermal efficiency of chemical heat pump 1 and chemical heat pump C1 as a comparative example was calculated. Chemical heat pump C1, as shown in Figure 2, has the same configuration as chemical heat pump 1 except that it does not have a second separation unit 20B and has only one distillation column, unlike chemical heat pump 1 which has two distillation columns. Table 1 shows the results of calculating the overall thermal efficiency of chemical heat pumps for chemical heat pump 1 and chemical heat pump C1 when the concentration of acetone in the raw material components supplied to the endothermic reaction unit 10 is the same.

[0061] [Table 1]

[0062] As shown in Table 1, under operating conditions where the isopropyl alcohol concentration in the bottom liquid of the tower is the same, the heat load of the first condenser 21A and the second condenser 21B of the two-tower chemical heat pump 1 is smaller than that of the first condenser 21A of the single-tower chemical heat pump C1. Therefore, it can be seen that chemical heat pump 1 achieves higher thermal efficiency than chemical heat pump C1 at the same acetone concentration in the raw material components.

[0063] [Other Embodiments] The present invention is not limited to the embodiments described above, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention.

[0064] For example, the reversible reaction system in the chemical heat pump of the present invention may be an isopropyl alcohol / acetone / hydrogen system, a methylcyclohexane / toluene / hydrogen system, or a cyclohexane / benzene / hydrogen system.

[0065] Both the first and second catalysts may be catalysts in which catalytically effective components are supported on carrier particles, such as the carbon-supported ruthenium catalyst described above, or they may be particles of the catalytically effective components themselves, such as the sponge nickel described above. The carrier particles may be made of materials other than activated carbon, such as silica or metal oxide particles such as alumina. Furthermore, these particles may be primary particles, secondary particles, or sintered bodies.

[0066] The endothermic reactor in the present invention may be appropriately selected from a range of reactors capable of sufficiently exchanging reaction heat between the granular catalyst and the raw material components flowing through the fixed bed of the catalyst. For example, it may be a plate reactor or a spiral reactor. These reactors are also preferable from the viewpoint of increasing the heat exchange efficiency in the endothermic reaction. Similarly, the exothermic reactor may also be a plate reactor or a spiral reactor for the same reasons.

[0067] The separation apparatus in the present invention may be appropriately determined according to the state of the raw material components and their decomposed components. For example, if the state of the raw material components and the state of the decomposed components is liquid and gas, a gas-liquid separation apparatus may be used in addition to the distillation column described above. If the states are gases, a gas adsorption apparatus capable of adsorbing and desorbing one of the gases may be used.

[0068] Furthermore, in the present invention, two endothermic reactors or two exothermic reactors may be arranged in parallel and switchably. This embodiment is preferable from the viewpoint of achieving both continuous operation of the chemical heat pump and replacement of the catalyst in the exothermic reactor.

[0069] The heat source for the endothermic reaction in the endothermic reactor of the present invention may be appropriately determined within a range that can supply the amount of heat required for the endothermic reaction. Examples of such heat sources include exhaust heat from an incinerator, waste hot water from a boiler, and waste heat from the top of a distillation plant. According to the present invention, it is possible to effectively utilize the waste heat from such various facilities. Furthermore, the heat generated by the exothermic reaction in the exothermic reactor of the present invention may be used for an appropriate purpose according to the amount of heat. For example, the heat generated by the exothermic reaction is suitably used to generate steam.

[0070] The chemical heat pump of the present invention described above can effectively utilize waste heat from external equipment. The present invention, which can provide a chemical heat pump that exhibits such effects, is expected to contribute to achieving goals such as Goal 7 of the United Nations' Sustainable Development Goals (SDGs), "Affordable and Clean Energy." [Explanation of Symbols]

[0071] 1. Chemical heat pump 10 Endothermic Reactor 11, 13, 23A, 23B, 24A, 24B, 26A, 26B, 28B, 31 Piping 12 pumps 20A First separation device 20B Second separation device 21A First Capacitor 21B Second Capacitor 22A First reflux tank 22B Second reflux tank 25A First Blower 25B Second Blower 27 Heat exchanger 29B Reboiler 30 Exothermic reaction apparatus

Claims

1. An endothermic reactor for supplying first thermal energy and for decomposing raw material components into their decomposed components through an endothermic reaction in the presence of a first catalyst, A first separation device for separating the decomposed components from the raw material components and decomposed components discharged from the endothermic reaction apparatus, A second separation device for separating the raw material components from the raw material components and decomposed components discharged from the first separation device, An exothermic reaction apparatus is provided to receive the decomposition components discharged from the first separation apparatus and to generate the raw material components from the decomposition components by an exothermic reaction in the presence of a second catalyst, and to output a second thermal energy higher than the first thermal energy, It has, A chemical heat pump configured such that the raw material components generated in the exothermic reaction device and the raw material components separated in the second separation device are supplied to the endothermic reaction device.

2. The chemical heat pump according to claim 1, wherein the raw material component is isopropyl alcohol and the decomposition component is acetone and hydrogen.

3. The second separation device is, A distillation column for distilling off the decomposed components from the raw material components and decomposed components discharged from the endothermic reaction apparatus, A condenser for cooling the components distilled from the aforementioned distillation column, A reflux tank for containing the liquid component generated in the aforementioned condenser, Includes, The chemical heat pump according to claim 1 or 2, wherein the gaseous component discharged from the condenser is supplied to the exothermic reaction device, and the raw material component contained in the reflux tank is supplied to the distillation column.

4. The second separation apparatus further comprises a circulation channel for circulating a portion of the bottom liquid of the distillation column, and a reboiler for heating the liquid in the circulation channel. The chemical heat pump according to claim 3, wherein the first thermal energy is supplied to the reboiler as thermal energy for heating the liquid.

5. The first catalyst is a granular catalyst, The chemical heat pump according to claim 1 or 2, wherein the endothermic reaction apparatus includes a fixed bed composed of the granular catalyst in the flow path of the raw material components.

6. The chemical heat pump according to claim 5, wherein the granular catalyst is one or both of activated carbon particles and a carbon-supported ruthenium catalyst containing ruthenium supported thereon, and sponge nickel.

7. The chemical heat pump according to claim 2, wherein the concentration of acetone in the liquid supplied from the second separation device to the endothermic reaction device is 4% by mass or less.

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