Steam generation device

Abstract

To provide a steam generation device capable of stably generating steam using a chemical thermal storage medium.SOLUTION: According to one embodiment, a steam generation device 100 includes: a plurality of thermal storage medium units 110 extending in the vertical direction, and arranged in array in which they are in parallel with each other having a predetermined interval; a heat transfer container 130 which stores the plurality of thermal storage medium units 110, and in which a flow passage is formed inside where steam, condensate water, water, and generated steam can pass between the plurality of thermal storage medium units 110; a reaction gas pipe 120 for introducing a reaction gas into a reaction gas flow passage 113; a steam inlet / outlet pipe 162; and a water inlet / outlet pipe 161. The thermal storage medium unit 110 includes a chemical thermal storage medium 111 in which the reaction gas flow passage is formed inside, which stores heat of the steam of a power generation system by an endothermic reaction, and which discharges the stored heat into the water of the power generation system.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] SUMMARY OF THE DISCLOSURE An embodiment of the present invention relates to a steam generating device. [Background technology]

[0002] In recent years, with the large-scale introduction of renewable energy, thermal power generation is expected to play a role as a regulator to maintain the balance between the supply and demand of electricity. Thermal storage technology has attracted attention as a method to improve the regulator and power generation efficiency of existing thermal power generation. Specifically, there are known methods such as a method of storing heat during steady operation and effectively utilizing the stored energy at start-up, and a method of using a thermal storage device as a buffer to operate a steam turbine with varying load while keeping the boiler load constant.

[0003] Among heat storage materials, a heat storage method using a chemical heat storage material that stores thermal energy through a chemical reaction is superior to other heat storage methods such as sensible heat storage and latent heat storage in that it can store heat semi-permanently.

[0004] Since chemical heat storage materials store heat through chemical reactions, they require the supply or removal of a reactive gas during heat storage and heat release. The reactive gas varies depending on the type of heat storage material. For example, when using a reaction between metal oxide and water vapor, the reactive gas is steam, so it can often be supplied directly from an existing process. This makes the system relatively simple, and costs can be reduced. In addition, when steam is used as a heat transfer medium during heat release, the generated steam can often be used directly in an existing process, which also makes it possible to reduce costs. Therefore, when steam is selected as a heat transfer medium for a chemical heat storage material that uses a reaction between metal oxide and water vapor, a cycle of heat storage and heat release is possible using only steam, and the range of industrial uses is wide.

[0005] Generally, the structure of steam generators (boilers) can be broadly divided into fire tube boilers (round boilers) and water tube boilers. Round boilers have a large diameter body filled with water (heat transfer medium) and have a flue inside. Water tube boilers have a combustion chamber in the body, and water tubes through which water (heat transfer medium) passes are arranged in the combustion chamber. Generally, round boilers have a large thermal inertia because the heat transfer medium accounts for a large proportion of the boiler, making them stable against load fluctuations. In contrast, water tube boilers have a large combustion chamber and a small proportion of the heat transfer medium, so although they are inferior to round boilers in terms of stable steam supply, they have good responsiveness and short start-up times.

[0006] Steam generators using chemical heat storage materials include those that mimic the boiler structure described above.Specifically, there are methods such as water tube boilers in which a heat transfer tube is passed through a heat storage material (zeolite) to supply the steam for reaction to the heat storage material, and structures such as round boilers and nuclear power plants in which a heating element such as a cylindrical hydrogen storage alloy is placed in water. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2016-161166 A [Patent Document 2] Patent Publication No. 2022-139945 [Patent Document 3] Patent No. 6571322 [Patent Document 4] Special Publication No. 4-70522 Summary of the Invention [Problem to be solved by the invention]

[0008] In steam generators that utilize the reaction between chemical heat storage materials such as metal oxides and reactive gases, the reaction heat per volume is smaller than that of heat storage technologies that use hydrogen, etc. This reduces the heat flux to the heat medium, making stable steam generation more difficult.

[0009] When the flow of the heat transfer medium is close to natural convection, the bubbles that are generated rise due to the effect of gravity, so in a structure with multiple water tubes arranged in parallel, there is a high possibility of unstable phenomena such as geysering occurring. As a result, there is an issue that the design costs increase due to the increase in vibration conditions that must be considered. For this reason, it is necessary to ensure flow conditions close to forced convection.

[0010] In addition, when the heat flux decreases due to the time change caused by the chemical reaction, steam generation becomes unstable, so a structure that can stabilize the flow field is required. Also, it is necessary to secure a sufficient heat transfer area to enable rapid steam generation.

[0011] An object of the present invention is to provide a steam generating device capable of stably generating steam in a system using a chemical heat storage material. [Means for solving the problem]

[0012] In order to achieve the above-mentioned object, the steam generating device according to the present embodiment is a steam generating device used in a power generation system that generates power using steam obtained by heating water, and has a chemical heat storage material that stores heat of the steam from the power generation system through an endothermic reaction and releases the stored heat to the water from the power generation system through an exothermic reaction of the chemical heat storage material, a reaction gas flow path that introduces a reaction gas for a reaction of the chemical heat storage material is formed inside the chemical heat storage material, a plurality of heat storage material units that extend in the vertical direction and are arranged in parallel with each other at predetermined intervals, and a plurality of the heat storage material units are housed inside and the steam from the power generation system and the front gas are passed between the plurality of the heat storage material units. The heat transfer system is characterized in that it comprises a heat transfer vessel in which a flow path is formed through which the condensed water caused by the phase change of the steam, as well as the water from the power generation system and the generated steam caused by the phase change of the water can pass; a reactant gas pipe connected to each of the plurality of heat storage material units for introducing the reactant gas into the reactant gas flow path; a steam inlet / outlet pipe connected to the heat transfer vessel for introducing the steam from the power generation system into the heat transfer vessel and serving as a flow path for supplying the generated steam to the power generation system; and a water inlet / outlet pipe connected to the heat transfer vessel for introducing the water from the power generation system into the heat transfer vessel and serving as a flow path for supplying the condensed water to the power generation system. [Brief description of the drawings]

[0013] [Figure 1] 1 is a block diagram conceptually illustrating a configuration example of a power generation system to which a steam generating device according to an embodiment is applied. [Diagram 2] 1 is an elevational cross-sectional view conceptually showing a configuration of a steam generating device according to an embodiment. [Diagram 3] FIG. 2 is a vertical cross-sectional view showing a configuration of a heat storage material unit of the steam generating device according to the embodiment. [Figure 4] FIG. 11 is a vertical cross-sectional view showing the configuration of a heat storage material unit according to a modified example of the steam generating device according to the embodiment. [Diagram 5] FIG. 2 is a horizontal cross-sectional view showing the configuration of a heat storage material unit of the steam generating device according to the embodiment. [Figure 6]FIG. 4 is a horizontal cross-sectional view showing the configuration of a heat storage material unit according to a first modified example of the steam generating device according to the embodiment. [Figure 7] FIG. 11 is a horizontal cross-sectional view showing the configuration of a heat storage material unit according to a second modified example of the steam generating device according to the embodiment. [Figure 8] FIG. 11 is a horizontal cross-sectional view showing the configuration of a heat storage material unit according to a third modified example of the steam generating device according to the embodiment. [Figure 9] FIG. 11 is a horizontal cross-sectional view showing the configuration of a heat storage material unit according to a fourth modified example of the steam generating device according to the embodiment. [Figure 10] FIG. 13 is a horizontal cross-sectional view showing the configuration of a heat storage material unit according to a fifth modified example of the steam generating device according to the embodiment. [Figure 11] FIG. 13 is a horizontal cross-sectional view showing the configuration of a heat storage material unit according to a sixth modified example of the steam generating device according to the embodiment. [Figure 12] 1 is a horizontal cross-sectional view conceptually showing a configuration of a steam generating device according to an embodiment. [Figure 13] FIG. 2 is a perspective view showing a spacer of a heat storage material unit of the steam generating device according to the embodiment. [Figure 14] FIG. 4 is a horizontal cross-sectional view showing an example of an arrangement of heat storage material units according to a modified example of the first shape of the steam generating device according to the embodiment. [Figure 15] FIG. 11 is a horizontal cross-sectional view showing an example of an arrangement of heat storage material units according to a modified example of the second shape of the steam generating device according to the embodiment. [Figure 16] FIG. 4 is an explanatory diagram supplementing the meaning of polygons in the shape of the steam generating device according to the embodiment. [Figure 17] FIG. 2 is an elevational cross-sectional view conceptually showing a state of a heat storage mode of the steam generating device according to the embodiment. [Figure 18] FIG. 2 is a cross-sectional elevation view conceptually showing a state of a first heat radiation mode of the steam generating device according to the embodiment. [Figure 19] FIG. 4 is a cross-sectional elevation view conceptually showing a state of a second heat radiation mode of the steam generating device according to the embodiment. [Figure 20] FIG. 11 is an elevational sectional view conceptually showing the configuration of a steam generating device according to a modified example of the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, a steam generating device according to an embodiment of the present invention will be described with reference to the drawings. Here, the same or similar parts are denoted by the same reference numerals, and overlapping descriptions will be omitted.

[0015] In the following, an example of application to a power generation system using water vapor is shown, so the heat medium of the steam generator described below is water / steam, and the gas for reaction with the chemical heat storage material is both steam, but this is not limited to this. In addition, the application is not limited to power generation systems, and may be any facility that requires the use of steam. Therefore, the connection to parts other than the steam generator in the system to which it is applied is shown below as one example, and is not limited to this.

[0016] The features of the embodiment relate to a configuration including a heat storage unit in a steam generating device described later, and can be applied even when the heat transfer medium and the reaction gas are other than water vapor. In addition, although the reactant with the chemical heat storage material is described as a reaction gas, it is not limited to a gas and may be a liquid. In the following examples, water and water vapor function as the heat transfer medium, and water vapor functions as the reaction material.

[0017] FIG. 1 is a block diagram conceptually illustrating a configuration example of a power generation system 1 to which a steam generating device 100 according to an embodiment is applied.

[0018] The power generation system 1 includes a boiler facility 10 as a heat source, a steam turbine facility 20 that converts thermal energy into mechanical energy, a generator 40 that converts mechanical energy into electrical energy, and a steam generating device 100 having a heat storage and heat release function.

[0019] The boiler facility 10 includes a boiler 11 that receives feed water and generates steam, and a reheat boiler 12 that receives steam and increases the degree of superheat. Note that, although the boiler facility 10 shown here has the boiler 11 and the reheat boiler 12 installed side by side, the boiler 11 and the reheat boiler 12 may be configured separately.

[0020] The steam turbine equipment 20 includes a main steam pipe 21, a high-pressure turbine 22, an intermediate-pressure turbine 25, a low-pressure turbine 27, a condenser 29, a condensate pipe 31, a condensate pump 32, a low-pressure feedwater heater 33, a deaerator 34, a feedwater pump 35, a feedwater pipe 36, and a high-pressure feedwater heater 37. has.

[0021] In the steam flow direction, the high-pressure turbine 22 is connected to the downstream side of the boiler 11 via a main steam pipe 21. The main steam pipe 21 is provided with a main steam stop valve 21a and a steam regulating valve 21b for shutting off the main steam and controlling the flow rate thereof.

[0022] The outlet side of the high-pressure turbine 22 is connected to the inlet of the reheat boiler 12 via a low-temperature reheat steam pipe 23. The outlet of the reheat boiler 12 is connected to the inlet of the intermediate-pressure turbine 25 via a high-temperature reheat steam pipe 24. The high-temperature reheat steam pipe 24 is provided with a reheat steam valve 24a for blocking the reheat steam, etc.

[0023] The outlet of the intermediate-pressure turbine 25 is connected to the inlet of the low-pressure turbine 27 via a crossover pipe 26. Although the case of the crossover pipe 26 is illustrated in Fig. 1, a cross-around pipe or a cross-under pipe may be used instead as long as the outlet of the intermediate-pressure turbine 25 and the inlet of the low-pressure turbine 27 are connected. The outlet of the low-pressure turbine 27 is connected by an exhaust pipe 28 to a condenser 29 that cools and condenses the exhaust steam.

[0024] An outlet of the condenser 29 is connected to the suction side of a feedwater pump 35 via a condensate pipe 31. A condensate pump 32, a low-pressure feedwater heater 33, and a deaerator 34 are provided in the condensate pipe 31. In addition, an outlet of the feedwater pump 35 is connected to the inlet of the boiler 11 via a feedwater pipe 36. A high-pressure feedwater heater 37 is provided in the feedwater pipe 36.

[0025] Some of the intermediate stages of the low-pressure turbine 27 are connected to a low-pressure feed water heater 33 via a low-pressure extraction pipe 27a. A control valve 27b is provided in the low-pressure extraction pipe 27a. An intermediate stage of the intermediate-pressure turbine 25 is connected to a deaerator 34 via an intermediate-pressure extraction pipe 25a. Also, an intermediate stage of the high-pressure turbine 22 is connected to a high-pressure feed water heater 37 via a high-pressure extraction pipe 22a. In this way, a regenerative cycle is formed in the steam turbine facility 20.

[0026] Since the deaerator 34 is of a direct contact type, the extraction steam flowing into the deaerator 34 through the medium-pressure extraction pipe 25a is mixed with the condensate flowing into the deaerator 34 and then sent to the feedwater pump 35. The extraction steam flowing into the low-pressure feedwater heater 33 through the low-pressure extraction pipe 27a is condensed by heat exchange in the low-pressure feedwater heater 33, and the condensed drain flows into the condenser 29 through a drain piping (not shown). In addition, the extraction steam flowing into the high-pressure feedwater heater 37 through the high-pressure extraction pipe 22a is condensed by heat exchange in the high-pressure feedwater heater 37, and the condensed drain flows into the upstream deaerator 34 through a drain piping (not shown).

[0027] The generator 40 is connected, for example, to the low-pressure turbine 27. Fig. 1 shows an example in which the rotors of the high-pressure turbine 22, the intermediate-pressure turbine 25, the low-pressure turbine 27, and the generator 40 are connected on a single shaft.

[0028] The steam generating device 100 is in the power generation system 1 and has a heat storage function and a heat dissipation function, and therefore, for example, stores heat when the output required for the power generation system 1 is smaller than the output of the boiler equipment 10, and dissipates heat when the output required for the power generation system 1 is greater than the output of the boiler equipment 10, thereby acting to eliminate the gap between the output of the boiler equipment 10 and the output required for the power generation system 1.

[0029] The piping connected to the steam generating system 100 includes a low-temperature side connecting pipe 171 branching off from the outlet side of the condensate pump 32 of the condensate pipe 31, a high-temperature side connecting pipe 172 joining the crossover pipe 26, a return pipe 173 returning to the condenser 29, a high-pressure steam pipe 174 branching off from the main steam pipe 21, a high-pressure steam exhaust pipe 175 joining the low-temperature reheat steam pipe 23, a low-pressure steam pipe 176 branching off from the low-pressure extraction pipe 27a, and a low-pressure steam exhaust pipe 177 connected to the condenser 29.

[0030] FIG. 2 is a cross-sectional elevation view conceptually showing the configuration of the steam generating device 100 according to the embodiment.

[0031] The steam generator 100 has a plurality of heat storage material units 110 arranged in parallel to one another and extending in the vertical direction, a cylindrical heat transfer vessel 130 with top and bottom lids that houses the plurality of heat storage material units 110, and a separator 150 arranged adjacent to the heat transfer vessel 130. Note that, although Fig. 12 illustrates an example in which the heat transfer vessel 130 is cylindrical, the shape is not limited to this, and for example, the cross section may be polygonal rather than circular.

[0032] Each heat storage material unit 110 is supported from below by a unit support portion 131. However, this is not limited to this, and other methods such as supporting from above and below may be used. The distance between the heat storage material units 110 is secured by spacers 114. The spacers 114 will be described later.

[0033] Each of the multiple heat storage material units 110 has a chemical heat storage material 111 and a storage container 112 that stores the chemical heat storage material 111. As the chemical heat storage material 111, a compound that can utilize reaction heat generated when adsorbing / desorbing or hydrating / dehydrating a reactant and can cause a reversible reaction, such as adsorbable / desorbable zeolite, hydrateable / dehydrateable magnesium chloride, magnesium oxide, calcium chloride, calcium oxide, and the like, can be used.

[0034] Here, zeolite as the adsorbable / desorbable chemical heat storage material 111 becomes H2O(g)→H2O(s) during adsorption, and becomes H2O(s)→H2O(g) during desorption. The hydratable / dehydrateable chemical heat storage material 111 has two states, for example, M(OH)2 obtained by an exothermic reaction that generates M(OH)2 from (MO+H2O), and MO obtained by an endothermic reaction that generates (MO+H2O) from M(OH)2 (for example, in the case where M is a divalent metal, but M may have another valence). Thus, the chemical heat storage material 111 has two states, an adsorbed or hydrated state, and a desorbed or dehydrated state. Hereinafter, both of the two states will be referred to as the chemical heat storage material 111. Note that M may be a metal with a valence of two or more.

[0035] A reactant gas channel section 113 that penetrates vertically is formed in the chemical heat storage material 111. The reactant gas channel section 113 is connected to a reactant gas pipe 120 that is connected to the storage container 112. In detail, a lower portion of the reactant gas channel section 113 is connected to each of the branch pipes 122 extending from a lower header 121 disposed below, and an upper portion of the reactant gas channel section 113 is connected to each of the branch pipes 124 extending from an upper header 123 disposed above.

[0036] The heat medium flow path 133 sandwiched between the heat storage material units 110 in the heat transfer container 130 serves as a flow path for heating steam from the crossover pipe 26 via the high temperature side connecting pipe 172 in a state of endothermic reaction of the chemical heat storage material 111 (heat storage mode), for condensed water from the condensate pipe 31 via the low temperature side connecting pipe 171 in a state of exothermic reaction of the chemical heat storage material 111 (heat release mode), and for water vapor generated by heating. Here, the steam in the heat storage mode, and the condensed water and generated water vapor in the heat release mode are collectively referred to as the heat medium.

[0037] Next, piping relating to the connection between the heat transfer vessel 130 and the separator 150, the connection between the heat transfer vessel 130 and the outside (inside the power generation system 1), and the connection between the separator 150 and the outside (inside the power generation system 1) will be described below.

[0038] First, the piping for the heat transfer medium (condensate and steam) is as follows:

[0039] The low-temperature side connecting pipe 171 branches into a water inlet / outlet pipe 161 and a separator branch pipe 165. A low-temperature side connecting pipe stop valve 171a is provided on the low-temperature side connecting pipe 171. The water inlet / outlet pipe 161 is connected to a portion above the bottom of the side surface of the heat transfer vessel 130. The separator branch pipe 165 is connected to the lower part of the separator 150. A separator branch valve 165a is provided on the separator branch pipe 165. A return pipe 173 connected to the condenser 29 branches off from the water inlet / outlet pipe 161. A return valve 173a is provided on the return pipe 173.

[0040] An upper portion of the side surface of the heat transfer vessel 130 is connected to an upper portion of the side surface of the separator 150 via a communication pipe 164. The separator 150 swirls the flowing steam using, for example, a guide plate to separate water droplets and moisture, and guides the separated steam to a steam outlet pipe 163.

[0041] A steam outlet pipe 163 connected to the top of the separator 150 and a steam inlet / outlet pipe 162 branching off from a communication pipe 164 are connected to each other and are linked to a downstream high-temperature side connecting pipe 172 and a return pipe 173. A steam inlet / outlet valve 162a is provided in the steam inlet / outlet pipe 162. A high-temperature side connecting pipe 172 is provided with a high-temperature side connecting pipe stop valve 172a.

[0042] Next, the piping for the reaction gas is as follows.

[0043] The upper header 123 of the reactive gas pipe 120 is connected to a high-pressure steam pipe 174 and a low-pressure steam pipe 176 at the outer end of the heat transfer vessel 130. The high-pressure steam pipe 174 and the low-pressure steam pipe 176 are provided with a high-pressure steam valve 174a and a low-pressure steam valve 176a, respectively.

[0044] The lower header 121 of the reaction gas pipe 120 is connected to a high-pressure steam exhaust pipe 175 and a low-pressure steam exhaust pipe 177 at the outer end of the heat transfer vessel 130. The high-pressure steam exhaust pipe 175 and the low-pressure steam exhaust pipe 177 are provided with a high-pressure steam exhaust valve 175a and a low-pressure steam exhaust valve 177a, respectively.

[0045] 3 is a vertical cross-sectional view showing the configuration of a heat storage material unit 110a according to a modified example of the steam generator 100 according to the embodiment. In this embodiment, a through hole penetrating vertically is formed in the chemical heat storage material 111. This through hole forms a reactant gas channel section 113. In addition, a connection pipe 113c that penetrates the upper and lower covers of the storage container 112 and communicates with the reactant gas channel section 113 is connected to the upper and lower covers of the storage container 112.

[0046] FIG. 4 is a vertical cross-sectional view showing the configuration of a heat storage material unit 110 of the steam generating device 100 according to the embodiment.

[0047] The heat storage material unit 110 has a storage container 112, a chemical heat storage material 111, and a ventilation member 113a. The storage container 112 has a rectangular cross section, extends vertically, and has lids at the top and bottom ends. The ventilation member 113a penetrates the chemical heat storage material 111 stored in the storage container 112, the chemical heat storage material 111, and the storage container 112 vertically, and a plurality of holes 113h are formed in the region penetrating the chemical heat storage material 111. The reactive gas flow passage section 113 allows the reactive gas formed inside the ventilation member 113a to flow, and is in communication with the chemical heat storage material 111. For example, a metal pipe with a plurality of holes formed on the side, a ceramic pipe, or a pipe made of a mesh material can be used as the ventilation member 113a.

[0048] FIG. 5 is a horizontal cross-sectional view showing the configuration of a heat storage material unit 110 of a steam generating device according to an embodiment.

[0049] Inside the heat storage material unit 110, there is provided a chemical heat storage material 111 having a square horizontal cross section, and a reactive gas flow path section 113 that vertically penetrates the chemical heat storage material 111. The surface of the heat storage material unit 110 that comes into contact with the heat medium is covered by a metal storage container 112, and the structure is such that the chemical heat storage material 111 and the heat medium do not come into direct contact with each other. In addition, the spacer 114 is attached to the storage container 112, for example, by welding.

[0050] 6 to 11 are horizontal cross-sectional views showing the configurations of heat storage material units according to first to sixth modified examples of the steam generator according to the embodiment. Including these modified examples, the horizontal cross-sectional shape of the reactant gas channel section 113 is not limited to a circle, and may be, for example, a square reactant gas channel section 113b as in the heat storage material unit 110b shown in Fig. 6. Furthermore, a plurality of reactant gas channel sections 113 may be provided as in the heat storage material unit 110c shown in Fig. 7.

[0051] Moreover, rectangular reactant gas channel sections 113b may be provided at intervals in the longitudinal direction in a chemical heat storage material 111 having a rectangular cross section, as in a heat storage material unit 110d shown in Fig. 8. A heat storage material unit 110g shown in Fig. 10 is a similar example in which the reactant gas channel section 113 has a circular cross section. Moreover, a heat storage material unit 110h shown in Fig. 11 is an example in which two rows of reactant gas channel sections 113 are provided in the longitudinal direction. Furthermore, instead of providing rectangular reactant gas channel sections 113b at intervals in the longitudinal direction of Fig. 8, a single reactant gas channel section 113c extending in the longitudinal direction may be provided as shown in Fig. 11.

[0052] In the above-mentioned examples, the arrangement of the reactant gas channel sections 113, 113b, and 113c can be determined based on the balance between the vapor diffusion rate and the heat diffusion rate in the heat storage material, and the pressure loss. When the vapor diffusion is the rate limiting factor, multiple reactant gas channel sections are provided, and when the pressure loss is large, the channel diameter is designed to be large.

[0053] Fig. 12 is a horizontal cross-sectional view conceptually showing the configuration of the steam generating device 100 according to the embodiment. Fig. 12 is a horizontal cross-sectional view taken along the line AA in Fig. 2, showing the heat transfer vessel 130 of the steam generating device 100. The direction from the left side to the right side in Fig. 12 is called the x direction, and the direction from the bottom to the top in Fig. 12 is called the y direction.

[0054] A plurality of heat storage material units 110, each having the same rectangular cross section, are housed inside the heat transfer container 130. Each of the plurality of heat storage material units 110 has a rectangular cross section that is long in the x direction. The plurality of heat storage material units 110 are arranged in parallel with one another in the x direction and the y direction. A gap of a specified width d1 is maintained between adjacent heat storage material units 110 by spacers 114 (FIG. 13), which will be described later with reference to FIG. 13.

[0055] By arranging in this manner, a dense arrangement is formed. Here, the dense arrangement refers to an arrangement in which the side surfaces of the heat storage material units 110 that are adjacent and facing each other are parallel to each other and a predetermined interval is secured. In addition, a cross-sectional shape that can form a dense arrangement is called a densely arranged shape. The densely arranged shape is not limited to the rectangle shown in FIG. 12. In addition, for example, a hexagon and a triangle exemplified later in FIG. 14 and FIG. 15, respectively, or other shapes such as a parallelogram and a trapezoid may be used. Furthermore, a polygon that can be enveloped by the densely arranged shape described later with reference to FIG. 16 may be used. In this case, being able to be enveloped includes the case of the same figure as the densely arranged shape.

[0056] The dense arrangement in this embodiment is achieved by making the heat storage material units 110 into a polygonal shape that can be enclosed by a shape that allows for dense arrangement, and by providing the heat storage material units 110 with spacers 114 that ensure a predetermined spacing.

[0057] The predetermined interval is an interval in the range of not less than the minimum interval dmin and not more than the maximum interval dmax. The minimum interval dmin is set as a value that does not cause excessive pressure loss in the heat storage material unit 110, and the maximum interval dmax is set as a value that makes the flow velocity of the heat medium in the heat medium passage 133, under the heat flux from the heat storage material unit 110, equal to or greater than a predetermined flow velocity.

[0058] Partition plate 132, shown by a solid line, is provided around heat storage material unit 110 at a predetermined width d2 at the portion where heat storage material unit 110 faces the inner surface of heat transfer vessel 130. Here, predetermined width d2 is equal to or smaller than predetermined width d1. The space inside heat transfer vessel 130 that is not occupied by heat storage material unit 110 is divided by partition plate 132 into an area of ​​inner heat medium flow path 133 surrounded by partition plate 132, and an area between partition plate 132 and the inner surface of heat transfer vessel 130.

[0059] As a result, the flow path of the heat transfer medium flowing in from the water inlet / outlet pipe 161 and rising within the heat transfer container 130 is formed with a flow path of width d1 between the heat storage material units 110 adjacent to each other in the x and y directions, and a flow path of width d2 between the heat storage material unit 110 and the partition plate 132.

[0060] One reactive gas flow path section 113 is formed in the chemical heat storage material 111 of each heat storage material unit 110. The lengths in the x and y directions of the cross section of the heat storage material unit 110 are determined based on the thermal conductivity of the chemical heat storage material 111, the diffusion speed of steam in the chemical heat storage material 111, the chemical reaction speed, etc. The width in the y direction of the cross section of the heat storage material unit 110, i.e., the length of the short side, is, for example, about 10 cm.

[0061] When setting the size and dimensions and widths d1 and d2 of the heat storage material unit 110, consideration is given to both the amount of chemical heat storage material 111 required to ensure stable generation of heat, and the flow rate of the heat transfer medium required to ensure stable flow of the heat transfer medium.

[0062] Furthermore, the longer the width in the y direction of the cross section of the heat storage material unit 110, i.e., the length of the long side, the fewer the number of heat storage material units 110 can be. However, the heat transfer area, i.e., the area of ​​the side surface, is reduced compared to an arrangement of heat storage material units 110 with relatively short long sides. Therefore, the length of the long side can be set taking into consideration both the advantage of reducing the number of heat storage material units 110 and the disadvantage of reducing the heat transfer area. Furthermore, multiple reactive gas channel sections 113 in one heat storage material unit 110 can be provided in the x direction, as necessary.

[0063] Here, two heat storage material units 110 adjacent to each other in the x direction may be formed as one heat storage material unit 110.

[0064] FIG. 13 is a perspective view showing a spacer 114 of a heat storage material unit 110 of a steam generating device 100 according to an embodiment.

[0065] For ease of explanation, the heat storage material unit 110 in the center of FIG. 13 is represented as heat storage material unit 110x, and the heat storage material unit 110 adjacent to heat storage material unit 110x is represented as heat storage material unit 110y.

[0066] First, the heat storage material unit 110x will be described. Spacers 114 are provided on the four side surfaces of the heat storage material unit 110x. The spacers 114 have an upper first spacer 114a and a lower first spacer 114b that differ only in their vertical height position. The spacers 114 have the same height H in the vertical direction. The height H is a height that ensures the bending rigidity of the spacers 114. The height d1 that protrudes out of the plane corresponds to the interval d1 between the heat storage material units 110 adjacent to each other. The protruding surface of the spacer 114 is flat. The ridge portion of the outermost surface of the spacer 114 may be chamfered.

[0067] The horizontal width of the spacer 114 is as follows.

[0068] The horizontal widths w1, w2 of the upper first spacer 114a on the side having a long side W1 and a short side W2 are made sufficiently smaller than the long side W1 and the short side W2, respectively, and the spacers 114 between each side are not continuous, so that the upward flow of the heat transfer medium is not obstructed.

[0069] The lower first spacers 114b are provided on the four side surfaces at height positions below the upper first spacers 114a.

[0070] In the heat storage material unit 110x shown in Figure 13, the upper first spacers 114a on the four side surfaces are at the same height position, and the lower first spacers 114b on the four side surfaces are also at the same height position. However, this is not limited to this example. For example, the height positions of the four side surfaces or some of the side surfaces may be different, and the height positions may be distributed to reduce the degree of reduction in the cross-sectional area of ​​the heat medium flow path 132 at each height position.

[0071] In the heat storage material unit 110y shown in Fig. 13, an upper second spacer 114c and a lower second spacer 114d are provided on each of four side surfaces. The height position of the upper second spacer 114c is below the height of the straight line L1 shown in Fig. 13. Meanwhile, the height position of the upper first spacer 114a is above the height of the straight line L1 shown in Fig. 13. Also, the height position of the lower second spacer 114d is below the height of the straight line L2 shown in Fig. 13. Meanwhile, the height position of the lower first spacer 114b is above the height of the straight line L2 shown in Fig. 13.

[0072] As described above, the spacers 114 attached to the heat storage material units 110x and 110y are at different height positions and therefore do not interfere with each other, and when the heat storage material units 110x and 110y are brought into close contact horizontally, a distance of height d1 between the spacers 114 is ensured. In other words, the width of the heat medium passage 132 in the horizontal cross section is d1.

[0073] Furthermore, the height positions of some or all of the four side surfaces of each of the upper first spacer 114a, the lower first spacer 114b, the upper second spacer 114c, and the lower second spacer 114d may be dispersed from one another. Alternatively, spacers 114 may be provided only on every other heat storage material unit 110 in the x and y directions (FIG. 12) of adjacent heat storage material units 110.

[0074] In addition, in FIG. 13, the spacer 114 attached to the heat storage material unit 110x and the spacer 114 attached to the heat storage material unit 110y do not interfere with each other, but this is not limited to the above. For example, the protruding height of the spacer 114 attached to the heat storage material unit 110x shown in FIG. 13 may be set to 1 / 2 of d1, and the spacer 114 attached to the heat storage material unit 110y may be set to the same height position as the spacer 114 attached to the heat storage material unit 110x, and the protruding height may be set to 1 / 2 of d1. That is, only one type of heat storage material unit 110x may be used. This makes it unnecessary to alternately arrange the heat storage material units 110x and 110y as shown in FIG. 13, and reduces the burden of arrangement management. Furthermore, the degree of reduction in the flow path area due to the spacer 114 in the heat medium flow path 132 is reduced compared to the case of FIG. 13.

[0075] FIG. 14 is a horizontal cross-sectional view showing an example of an arrangement of heat storage material units 110b according to a modified example of the first shape of the steam generating device 100 according to the embodiment.

[0076] Heat storage material unit 110b has storage container 112b with a hexagonal cross section, which is a shape that can be densely arranged differently from storage container 112 of heat storage material unit 110b shown in Fig. 12. Here, a hexagon is one in which the lengths of opposing sides are equal. Fig. 14 shows a case in which, instead of a regular hexagon, the width of a pair (two) of opposing sides (long sides) is greater than the widths of the other four sides (short sides) in the cross section.

[0077] The long sides of adjacent heat storage material units 110b are parallel to each other, with a predetermined distance d3 between them. The short sides of adjacent heat storage material units 110b are also parallel to each other, with a predetermined distance d4 between them. Therefore, a dense arrangement is also formed in this case.

[0078] Here, the distance d3 and the distance d4 may be equal to each other. Alternatively, the distance d3 and the distance d4 may be set so that the flow rate of the heat medium in the flow passage between the long sides is equal to the flow rate of the heat medium in the flow passage between the short sides.

[0079] Fig. 15 is a horizontal cross-sectional view showing an example of an arrangement of heat storage material units 110c according to a modified example of the second shape of the steam generating device 100 according to the embodiment. Fig. 15 shows a part of the entire arrangement of the heat storage material units 110c. Each of the heat storage material units 110c has a triangular cross section as a shape that can be densely arranged.

[0080] The sides of adjacent heat storage material units 110c are parallel to each other, and a predetermined distance d5 is ensured between them. Therefore, in this case as well, a close-packed arrangement is formed.

[0081] Here, the distance d5 may be set so that the flow rate of the heat medium in the flow path is a predetermined flow rate.

[0082] Fig. 16 is an explanatory cross-sectional view supplementing the meaning of a polygonal column, i.e., a shape whose horizontal cross section is a polygon, with respect to the shape of the steam generating device according to the embodiment. The solid lines in Fig. 16 show an example of an octagon as an example of a polygon. The dashed lines show a rectangle that envelops this octagon. When polygons are densely arranged, adjacent side surfaces are parallel to each other at the overlapping portion with the enveloping rectangle. Therefore, the polygon can be enveloped by a shape that can be densely arranged.

[0083] 17 is an elevational cross-sectional view conceptually showing a state of the heat storage mode of the steam generating device according to the embodiment. The heat storage mode is a mode in which, for example, during steady operation in which the power generation system 1 is in a power generation state, steam (heat medium) is received from a high-temperature steam (heat medium) source, and the heat received from the steam (heat medium) by the endothermic reaction of the chemical heat storage material 111 is stored in the chemical heat storage material. Here, the high-temperature steam source is the crossover pipe 26 in the example shown in FIG. 1.

[0084] In the heat storage mode, the return valve 173a, the steam inlet / outlet valve 162a, and the high-temperature side connecting pipe stop valve 172a are open, while the low-temperature side connecting pipe stop valve 171a, the separator branch valve 165a, and the communication valve 164a are closed.

[0085] Regarding the open / close states of the valves on the reactive gas side of the heat storage material unit 110, the low-pressure steam exhaust valve 177a is open, and the high-pressure steam valve 174a, the high-pressure steam exhaust valve 175a, and the low-pressure steam valve 176a are closed.

[0086] In such a configuration, the pressure relationship in the heat transfer vessel 130 is reversed. That is, the pressure on the side of the high-temperature side connecting pipe 172 connected to the crossover pipe 26 is higher than the pressure on the side of the return pipe 173 connected to the condenser 29. Therefore, the steam on the crossover pipe 26 side flows in from the upper part of the heat transfer vessel 130 through the high-temperature side connecting pipe stop valve 172a and the steam inlet / outlet valve 162a on the high-temperature side connecting pipe 172 side. The steam that has heated the heat storage material unit 110 in the heat transfer vessel 130 basically becomes condensed water (drainage). Note that, in some cases, the steam flows out of the heat transfer vessel 130 as steam with reduced enthalpy. The steam or drainage that flows out of the heat transfer vessel 130 flows into the condenser 29 through the return pipe 173 via the return valve 173a. Note that the return valve 173a may be a pressure control valve or a flow rate control valve.

[0087] In such a situation, the endothermic reaction of the following formula (1) takes place in the chemical heat storage material 111 of the heat storage material unit 110.

[0088] M(OH)2->MO+H2O (1)

[0089] In the formula (1), M represents a monovalent metal such as Mg, but is not limited thereto and may be a divalent or higher metal.

[0090] The steam generated by this reaction is discharged from low-pressure steam discharge pipe 177 to condenser 29 via low-pressure steam discharge valve 177a.

[0091] As a result, energy from the heat medium is stored in the chemical heat storage material 111, and the chemical heat storage material 111 comes to have a heat dissipation function.

[0092] 18 is an elevational cross-sectional view conceptually showing a state of the heat release first mode of the steam generating device 100 according to the embodiment. The heat release mode is a mode in which, for example, at the start of the power generating system 1, water (heat medium) is received from a low-temperature water (heat medium) source, and the heat medium is heated by heat generated in the chemical heat storage material 111 by an exothermic reaction of the chemical heat storage material 111 to generate steam. Here, the low-temperature water source is the condenser pipe 31 in the example shown in FIG. 1.

[0093] Regarding the valve opening / closing state of the heat transfer medium side, the low-temperature side connecting pipe stop valve 171a, the separator branch valve 165a, the communication valve 164a, and the high-temperature side connecting pipe stop valve 172a are all open, and the steam inlet / outlet valve 162a and the return valve 173a are closed.

[0094] Regarding the open / close states of the valves on the reactive gas side of the heat storage material unit 110, the high-pressure steam valve 174a and the low-pressure steam valve 176a are open, and the high-pressure steam exhaust valve 175a and the low-pressure steam exhaust valve 177a are closed.

[0095] In this situation, when steam is supplied from the high-pressure steam pipe 174 and the low-pressure steam pipe 176, an exothermic reaction of the following formula (2) takes place in the heat storage material unit 110.

[0096] MO+H2O->M(OH)2 (2)

[0097] The water (condensate) flowing in from the low-temperature side connecting pipe stop valve 171a rises up the heat medium flow path 133 between the heat storage material units 110 in the heat transfer container 130, is heated by the heat storage material units 110, boils, and finally turns into steam (generated steam), which flows into the separator 150 via the connecting pipe 164, whose connecting valve 164a is in the open state.

[0098] The steam that flows into the separator 150 has the moisture contained therein removed in the separator 150, and then flows through the steam outlet pipe 163 and the high-temperature side connecting pipe stop valve 172a, into the high-temperature side connecting pipe 172, and into the crossover pipe 26.

[0099] FIG. 19 is a cross-sectional elevation view conceptually showing the state of the steam generating device 100 according to the embodiment in the second heat radiation mode.

[0100] The second heat release mode differs from the first heat release mode only in that the communication valve 164a is in a closed state in the valve opening / closing state on the heat medium side. This mode is a state in which the condensate that flows in from the low-temperature side connecting pipe stop valve 171a rises in the heat medium flow path 133 between the heat storage material units 110 in the heat transfer vessel 130 and is heated by the heat storage material units 110 until it finally becomes superheated steam. Since it is superheated steam, moisture separation in the separator 150 is not necessary. Therefore, by not passing through the separator 150, there is an advantage in that no pressure loss occurs in the separator 150.

[0101] Even when superheated steam is being generated, the valves may be in the same open / closed state as in the heat release mode 1. Alternatively, both the steam inlet / outlet valve 162a and the communication valve 164a may be in an open state.

[0102] 18 and in the second heat release mode shown in Fig. 19, the condensate (heat medium) flowing in from the lower hole 130a of the heat transfer container 130 rises in a heat medium flow path 133 formed outside the heat storage material unit 110, in the space inside the partition plate 132 in the heat transfer container 130. The heat medium rising in the heat medium flow path 133 acquires heat by heat exchange with the heat storage material unit 110 containing the chemical heat storage material 111 undergoing an exothermic reaction, and its temperature rises, becoming steam.

[0103] By arranging the heat storage material units 110 in parallel inside the heat transfer container 130 and making the area sandwiched between the heat storage material units 110 into heat medium flow paths 133, the heat medium flow paths 133 are connected horizontally in the inner space of the partition plate 132. As a result, problems such as geysering and channel instability do not occur as occurs with a group of heat transfer tubes that are arranged in parallel and extend vertically.

[0104] Furthermore, by arranging the heat storage material units 110 densely and setting the interval between the heat storage material units 110 within a prescribed range using spacers 114, the flow loss of the heat medium in the heat medium flow passage 133 is kept appropriate and the heat medium rises at a prescribed rising speed or higher. As a result, stable flow conditions for the heat medium are secured, enabling stable generation of steam.

[0105] FIG. 20 is an elevational sectional view conceptually showing the configuration of a steam generating device 100a according to a modified example of the embodiment.

[0106] In the steam generator 100a according to the modified example, a reactant gas channel section 113f that does not penetrate the upper part is formed in each heat storage material unit 110 instead of the reactant gas channel section 113. Therefore, the configuration of the reactant gas pipe 120 is partially different. That is, the lower header 121 of the reactant gas pipe 120 is connected to a high-pressure steam pipe 174, a low-pressure steam pipe 176, and a low-pressure steam exhaust pipe 177 at an end portion that is outside the heat transfer vessel 130. The high-pressure steam pipe 174, the low-pressure steam pipe 176, and the low-pressure steam exhaust pipe 177 are provided with a high-pressure steam valve 174a, a low-pressure steam valve 176a, and a low-pressure steam exhaust valve 177a, respectively.

[0107] On the other hand, the configuration of the heat medium side is the same as in the embodiment. Therefore, only the connection relationship between the steam supplied to the chemical heat storage material 111 and the released water and steam and the outside in the heat storage mode in which heat is given from the heat medium side to the heat storage material unit 110 and the heat release mode in which heat is given from the heat storage material unit 110 to the heat medium side is different.

[0108] Specifically, in the heat storage mode, the high-pressure steam valve 174a and the low-pressure steam valve 176a are closed, and the low-pressure steam exhaust valve 177a is opened. As a result, water and steam generated by the reaction shown in formula (1) are exhausted to the condenser 29 via the low-pressure steam exhaust pipe 177. Conversely, in the heat release mode, the low-pressure steam exhaust valve 177a is closed, and the high-pressure steam valve 174a and the low-pressure steam valve 176a are opened. As a result, steam is supplied from the high-pressure steam pipe 174 and the low-pressure steam pipe 176, the reaction shown in formula (2) progresses, and heat is generated.

[0109] As described above, in this embodiment, the same effect as in the embodiment can be obtained simply by supplying and discharging water and steam from the lower header 121 side.

[0110] According to the embodiment described above, it is possible to provide a steam generating device capable of stably generating steam in a system using a chemical heat storage material.

[0111] [Other embodiments] Although the embodiments of the present invention have been described above, the embodiments are presented as examples and are not intended to limit the scope of the invention. In addition, the features of each embodiment may be combined. Furthermore, the embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. The embodiments and their modifications are included in the scope of the invention and its equivalents as described in the claims, as well as in the scope and gist of the invention. [Explanation of symbols]

[0112] 1...power generation system, 10...boiler equipment, 11...boiler, 12...reheat boiler, 20...steam turbine equipment, 21...main steam pipe, 21a...main steam stop valve, 21b...steam control valve, 22...high pressure turbine, 22a...high pressure extraction pipe, 23...low temperature reheat steam pipe, 24...high temperature reheat steam pipe, 24a...reheat steam valve, 25...intermediate pressure turbine, 25a...intermediate pressure extraction pipe, 26...crossover pipe, 27...low pressure turbine, 27a...low pressure extraction pipe, 27b...control valve, 28...exhaust pipe, 29...condenser, 31... Condensate pipe, 32... condensate pump, 33... low pressure feed water heater, 34... deaerator, 35... feed water pump, 36... feed water pipe, 37... high pressure feed water heater, 40... generator, 100... steam generator, 110, 110a, 110b, 110c, 110d, 110f, 110g, 110h... heat storage material unit, 111... heat storage material, 112... storage container, 113... reactant gas flow passage portion, 113a... ventilation member, 113b... connecting pipe, 113f... reactant gas flow passage portion, 114... spacer, 114a... upper first Spacer, 114b...lower first spacer, 114c...upper second spacer, 114d...lower second spacer, 120...reaction gas pipe, 121...lower header, 122...branch pipe, 123...upper header, 124...branch pipe, 130...heat transfer vessel, 130a...lower hole, 130b...upper hole, 131...unit support part, 132...partition plate, 133...heat medium flow path, 150...separator, 161...water inlet / outlet pipe, 162...steam inlet / outlet pipe, 162a...steam inlet / outlet valve, 163...steam outlet pipe, 164...communicating pipe, 164a...communicating valve, 165...separator branch pipe, 165a...separator branch valve, 171...low temperature side connecting pipe, 171a...low temperature side connecting pipe stop valve, 172...high temperature side connecting pipe, 172a...high temperature side connecting pipe stop valve, 173...return pipe, 173a...return valve, 174...high pressure steam pipe, 174a...high pressure steam valve, 175...high pressure steam exhaust pipe, 175a...high pressure steam exhaust valve, 176...low pressure steam pipe, 176a...low pressure steam valve, 177...low pressure steam exhaust pipe, 177a...low pressure steam exhaust valve

Claims

1. A steam generating device used in a power generation system that generates power using steam obtained by heating water, A chemical heat storage material stores heat of the steam from the power generation system through an endothermic reaction and releases the stored heat to water from the power generation system through an exothermic reaction of the chemical heat storage material, and a reaction gas flow path for guiding a reaction gas for the reaction of the chemical heat storage material is formed inside the chemical heat storage material, and a plurality of heat storage material units are provided in parallel at predetermined intervals, extending in a vertical direction; a heat transfer vessel that houses a plurality of the heat storage material units and has flow paths formed therein through which the steam from the power generation system and condensed water resulting from a phase change of the steam, and the water from the power generation system and the steam generated by a phase change of the water can pass between the plurality of the heat storage material units; a reactant gas pipe connected to each of the plurality of heat storage material units for introducing the reactant gas into the reactant gas flow path; a steam inlet / outlet pipe connected to the heat transfer vessel, the steam being introduced from the power generation system into the heat transfer vessel, and serving as a flow path for supplying the generated steam to the power generation system; a water inlet / outlet pipe connected to the heat transfer vessel, the water from the power generation system being introduced into the heat transfer vessel, and the water inlet / outlet pipe being a flow path for supplying the condensed water to the power generation system; A steam generating device comprising:

2. The steam generating device according to claim 1, characterized in that an arrangement of the plurality of heat storage material units is formed by using spacers that ensure a flow path of a predetermined width between adjacent plurality of heat storage material units, and by the horizontal cross-sectional shape of each of the plurality of heat storage material units being a polygon that is enveloped by a shape that can be densely arranged.

3. 3. The steam generating apparatus according to claim 2, wherein the spacers are provided on side surfaces of at least every other one of the plurality of heat storage material units.

4. 2. The steam generating apparatus according to claim 1, wherein each of the plurality of heat storage material units has a ventilation member extending vertically and connected to the reactant gas pipe to guide the reactant gas.

5. The steam generating device according to claim 1, characterized in that each of the plurality of heat storage material units has an air hole formed in the chemical heat storage material, extending vertically, connected to the reaction gas pipe, and guiding the reaction gas.

6. 2. The steam generating apparatus according to claim 1, wherein the reaction gas pipe is connected to a lower portion of each of the plurality of heat storage material units.

7. 7. The steam generating apparatus according to claim 6, wherein the reactive gas pipe is further connected to an upper portion of each of the plurality of heat storage material units.

8. 8. The steam generating apparatus according to claim 1, further comprising a separator connected to the heat transfer vessel for separating moisture from the steam generated in the heat transfer vessel.

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