Boiler

Abstract

Provided is a boiler capable of appropriately heating a heat exchanger tube even in a situation where the temperature of a heating element is relatively low. This boiler comprises a heating element, a heat exchanger tube, a container with the heat exchanger tube inside, and a circulation path that can circulate gas with a higher specific heat than air and includes the interior of the container. The heating element is disposed in the gas introduction portion of the container, which is a portion of the circulation path. The gas flowing into the gas introduction portion from outside the container heats the heat exchanger tube using the heat obtained from the heating element, and flows out from the gas outlet portion of the container.

Description

Technical Field

[0001] The present invention relates to a boiler. This application claims priority based on Japanese Patent Application No. 2020-045121 filed in Japan on March 16, 2020, the content of which is incorporated herein by reference.

Background Art

[0002] Conventionally, boilers have been widely used for various applications including industrial and commercial use. In a boiler, a heat generating means for heating is provided.

[0003] Although various specific forms of the heat generating means can be cited, as an example, a reactor in which a plurality of metal nanoparticles made of a hydrogen storage metal or a hydrogen storage alloy are formed on the surface is used, and is disclosed in Patent Document 1 as a heat generating system. According to Patent Document 1, in this heat generating system, it is described that hydrogen atoms are occluded in the metal nanoparticles by supplying a hydrogen-based gas that contributes to heat generation into the container, and excess heat is generated.

[0004] As also described in Patent Document 1, a heat generating body made of palladium is provided inside a container, and while supplying deuterium gas into this container, heating the inside of the container causes a heat generating reaction. In addition, regarding the heat generating phenomenon of generating excess heat (output enthalpy higher than the input enthalpy) using a hydrogen storage metal or a hydrogen storage alloy, the details of the mechanism for generating excess heat have been debated among researchers in various countries, and it has been reported that the heat generating phenomenon has occurred.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] As a form of heating a heat transfer tube using a heating element, for example, a form of applying a gas heated by the heating element to the heat transfer tube can be considered. However, when adopting such a form, in a situation where the temperature of the heating element is relatively low (for example, a situation where there is not enough heat from the heating element), it may be difficult to raise the temperature of the gas, and it may be difficult to appropriately heat the heat transfer tube.

[0007] In view of the above problems, an object of the present invention is to provide a boiler capable of appropriately heating a heat transfer tube even in a situation where the temperature of the heating element is relatively low.

Means for Solving the Problems

[0008] The boiler according to the present invention includes a heating element, a heat transfer tube, a container in which the heat transfer tube is provided inside, a flow path that can circulate a gas having a higher specific heat than air, including the inside of the container, and a gas introduction part of the container, which is a part of the flow path, is provided with the heating element, and the gas flowing into the gas introduction part from the outside of the container heats the heat transfer tube using the heat obtained from the heating element and flows out from the gas outlet part of the container. According to this configuration, it is possible to appropriately heat the heat transfer tube even in a situation where the temperature of the heating element is relatively low.

[0009] More specifically, as the above configuration, the heating element may be arranged so as to cover the entire gas introduction part. Also, more specifically, as the above configuration, the gas introduction part may be a guide member formed so that the inside expands as it goes in the gas flow direction.

[0010] Furthermore, more specifically, as the above configuration, the heating element may be plate-shaped with a large number of holes. Also, in the above configuration, the flow path may be a circulation path for circulating the gas.

[0011] More specifically, as the above configuration, the gas is a hydrogen-based gas, the heating element is provided with metal nanoparticles made of hydrogen storage metals on its surface, and in a situation where the hydrogen-based gas is supplied to the flow path, it may be configured as a reactant in which hydrogen atoms are occluded in the metal nanoparticles to generate excess heat. Note that the hydrogen-based gas in the present application refers to deuterium gas, light hydrogen gas, or a mixed gas thereof. Also, the "hydrogen storage metals" in the present application means hydrogen storage metals such as Pd, Ni, Pt, Ti, or a hydrogen storage alloy containing one or more of these.

Advantages of the Invention

[0012] According to the boiler according to the present invention, it is possible to appropriately heat the heat transfer pipe even in a situation where the temperature of the heating element is relatively low.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0014] The boiler according to the embodiment of the present invention will be described below with reference to the respective drawings. FIG. 1 is a schematic configuration diagram of the boiler 1 according to the present embodiment. FIG. 2 is a schematic arrow view of the A-A cross section shown in FIG. 1, and FIG. 3 is a schematic arrow view of the B-B cross section shown in FIG. 1. Note that for the container 11 and the components around it, the up-down, left-right, and front-back directions (directions perpendicular to each other) are as shown in each figure, and in the example of the present embodiment, the up-down direction coincides with the vertical direction.

[0015] As shown in FIGS. 1 to 3, the boiler 1 includes a container 11, a reactant 12, a gas path 14, a gas receiving portion 15, a gas pump 16, a gas filter 17, a first guide member 18, a second guide member 19, a separator 21, a water path 22, a water receiving portion 23, and a water pump 24.

[0016] The container 11 has a cylindrical side wall with the vertical direction as the axial direction, and is formed so that gas can be sealed inside. A lower header 22b is provided on the lower side of the container 11, and an upper header 22c is provided on the upper side of the container 11.

[0017] The outlet side of the first guide member 18 is connected to the left side of the side wall of the container 11, and the inside of the container 11 and the inside of the first guide member 18 are connected. Further, the inlet side of the second guide member 19 is connected to the right side of the side wall of the container 11, and the inside of the container 11 and the inside of the second guide member 19 are connected. A plurality of heat transfer tubes 22a extending vertically are arranged inside the container 11.

[0018] The reactant 12 is configured by providing a large number of metal nanoparticles on the surface of a carrier that is entirely formed in a fine mesh shape. As the carrier, hydrogen storage alloys (hydrogen storage metals or hydrogen storage alloys) are applied as materials. In the example of this embodiment, it is formed in a rectangular parallelepiped shape (plate shape) according to the internal shape closer to the outlet side of the first guide portion 18. Since the above carrier is formed in a mesh shape, the reactant 12 has a plate shape with a large number of holes (mesh-shaped gaps) through which gas can pass. The reactant 12 is arranged inside the first guide member 18 closer to the outlet side. Thereby, the gas in the first guide member 18 can pass through the entire reactant 12.

[0019] In addition, a heater (for example, a ceramic heater) that generates heat by power supply is spirally wound around the reactant 12. When this heater generates heat, the temperature of the reactant 12 can be raised to a predetermined reaction temperature at which a reaction for generating excess heat described later is likely to occur, thereby heating the reactant 12. The temperature of the heater can be adjusted by controlling the supplied power.

[0020] The gas path 14 is a path for gas provided outside the container 11, and forms a gas circulation path S together with the inside of the container 11 and the inside of each guide member 18, 19. The gas path 14 is mainly provided as a tubular body and extends from the outlet side of the second guide member 19 to the inlet side of the first guide member 18. Along the gas path 14 in order from the upstream side, a gas receiving portion 15, a gas pump 16, and a gas filter 17 are provided.

[0021] The gas receiving portion 15 is configured to receive the supply of a hydrogen-based gas (deuterium gas, light hydrogen gas, or a mixed gas thereof) from an external supply source, and cause the supplied hydrogen-based gas to flow into the gas path 14. For example, when the hydrogen-based gas is supplied from a tank in which the hydrogen-based gas is stored in advance to the gas receiving portion 15, this tank serves as the supply source of the hydrogen-based gas.

[0022] The gas pump 16 has its rotation speed controlled, for example, by inverter control, and causes the gas in the gas path 14 to flow from the upstream side to the downstream side (that is, in the direction indicated by the dotted arrow in FIG. 1) at a flow rate corresponding to this rotation speed. Note that the circulation amount of the gas in the circulation path S including the gas path 14 can be adjusted by controlling the rotation speed of the gas pump 16.

[0023] The gas filter 17 removes impurities contained in the gas in the gas path 14 (particularly those that become factors inhibiting the reaction that generates excessive heat in the reactant 12). The separator 21 receives the steam generated when water is heated as it passes through the heat transfer tube 22a, and performs gas-liquid separation (separation of the drain contained in the steam) on this steam. The steam that has undergone gas-liquid separation in the separator 21 can be supplied to the outside of the boiler 1.

[0024] The first guide member 18 is interposed between the downstream end of the gas path 14 and the container 11, and is formed such that its interior expands as it extends from the inlet side (the side closer to the gas path 14) where the hydrogen-based gas flows in to the outlet side (the side closer to the container 11) where the hydrogen-based gas flows out. As is apparent from FIGS. 1 to 3, the first guide member 18 in the example of this embodiment is generally formed in the shape of a substantially quadrangular pyramid with the inlet side as the apex and the outlet side as the bottom surface. Note that the first guide member 18 is formed with an overall substantially uniform thickness, and the internal cavity also has a substantially quadrangular pyramid shape.

[0025] Therefore, the interior of the first guide member 18 expands in both the vertical and front-rear directions as it extends from the inlet side to the outlet side, that is, as it progresses rightward. Since the interior of the first guide member 18 gradually expands from the inlet side to the outlet side in this way, the gas can flow smoothly from the gas path 14 into the container 11, and the gas can be applied to most of the heat transfer tubes 22a arranged in the container 11 as uniformly as possible. Note that the first guide member 18 corresponds to the gas introduction portion 52 (the portion for introducing gas into the container 11) of the container 11, which is a part of the flow path 51 through which the gas flows. Also, the forms of the gas introduction portion and the gas outlet portion 53 (the portion for discharging gas outside the container 11) of the container 11 do not necessarily have to be the first guide member 18 and the second guide member 19, respectively, and for example, the cross-sectional shape of the flow path may be the same and the area may be the same.

[0026] The second guide member 19 is interposed between the container 11 and the upstream end of the gas path 14, and is formed such that its interior becomes narrower as it extends from the inlet side (the side closer to the container 11) where the hydrogen-based gas flows in to the outlet side (the side closer to the gas path 14) where the hydrogen-based gas flows out. In the example of this embodiment, the second guide member 19 is formed in the same size as the first guide member 18 but with a left-right reversed shape. Since the interior of the second guide member 19 gradually becomes narrower from the inlet side to the outlet side in this way, the gas can flow smoothly from the wide opening provided in the container 11 into the gas path 14.

[0027] The water path 22 is a path for water that connects from the water receiving part 23 to the separator 21. The water path 22 includes a plurality of heat transfer tubes 22a provided inside the container 11, a lower header 22b, and an upper header 22c. More specifically, the water path 22 extends from the water receiving part 23 to the separator 21 through the water pump 24, the lower header 22b, the plurality of heat transfer tubes 22a, and the upper header 22c in sequence.

[0028] The plurality of heat transfer tubes 22a are each arranged to extend vertically between the lower header 22b and the upper header 22c. Also, as shown in FIG. 2, each heat transfer tube 22a is arranged to spread in a zigzag pattern in the front-back, left-right directions when viewed from above, and is efficiently accommodated within the container 11. In the path of the water path 22 upstream of the heat transfer tubes 22a, the liquid water supplied from the water receiving part 23 flows, and in the path downstream of the heat transfer tubes 22a, the water (steam) heated and vaporized by the heat transfer tubes 22a flows.

[0029] The water receiving part 23 is adapted to appropriately receive the supply of water that is the source of steam from the outside, and allows the supplied water to flow into the water path 22. The water pump 24 causes the water in the water path 22 to flow from the upstream side to the downstream side (that is, in the direction indicated by the solid line arrow in FIG. 1).

[0030] Next, the operation of the boiler 1 will be described. In the boiler 1, a hydrogen-based gas is supplied from an external supply source to the gas receiving part 15, and the hydrogen-based gas fills the gas circulation path S. The filled hydrogen-based gas circulates in the gas circulation path S in the direction indicated by the dotted line arrow in FIG. 1 due to the action of the gas pump 16.

[0031] At this time, the hydrogen-based gas that has flowed into the interior of the first guide member 18 passes through a large number of holes in the reactant 12, then hits the heat transfer tube 22a in the container 11, and is sent to the gas path 14 through the second guide member 19. Note that the hydrogen-based gas comes into contact with the reactant 12 when passing through the large number of holes in the reactant 12. Furthermore, since a gap is provided between adjacent heat transfer tubes 22a, the hydrogen-based gas that has flowed into the container 11 passes through the gap and hits all the heat transfer tubes 22a almost evenly.

[0032] At the same time, the reactant 12 is heated by the action of the heater described above. In this way, when the reactant 12 is heated by the heater while circulating the hydrogen-based gas in the circulation path S, hydrogen atoms are occluded in the metal nanoparticles provided in the reactant 12, and the reactant 12 generates excess heat above the heating temperature by the heater. In this way, the reactant 12 functions as a heating element when a reaction that generates excess heat occurs. The principle of this reaction that generates excess heat is the same as, for example, the principle of the reaction that generates excess heat disclosed in Patent Document 1. Note that the reactant 12 (heating element) disposed in the first guide member 18 is provided such that the hydrogen-based gas passes through the entire reactant 12. Furthermore, the heat of the reactant 12 is transmitted to the heat transfer tube 22a by convection, heat conduction, and radiation, so that the heat transfer tube 22a is heated. Therefore, it is possible to very efficiently transfer the heat generated by the reactant 12 to the hydrogen-based gas.

[0033] When the reactant 12 generates excess heat and becomes high temperature, the hydrogen-based gas circulating in the circulation path S is also heated by the heat of the reactant 12 and becomes high temperature. Then, the hydrogen-based gas that has become high temperature hits a plurality of heat transfer tubes 22a in the container 11 and heats them. Note that in the present embodiment, since each heat transfer tube 22a is disposed immediately downstream of the reactant 12, the hydrogen-based gas immediately after being directly heated by the reactant 12 can be applied to the heat transfer tube 22a, and the heat transfer tube 22a can be effectively heated.

[0034] In addition, when the hydrogen-based gas in the circulation path S passes through the gas filter 17, impurities are removed. Therefore, it is possible to stably supply the highly pure hydrogen-based gas with impurities removed to the reactant 12, maintain a state in which it is easy to induce the output of excess heat, and effectively heat the reactant 12 to generate heat.

[0035] In addition, in parallel with the operation of heating the heat transfer tube 22a by heating the reactant 12, water is supplied from the outside to the water receiving portion 23. The supplied water is caused to flow through the water path 22 in the direction indicated by the solid line arrow in FIG. 1 by the action of the water pump 24.

[0036] The water flowing through the water path 22 is heated when passing through the plurality of heat transfer tubes 22a in the container 11, and the temperature rises, and finally becomes steam. This steam is sent to the separator 21, and after the dryness is increased by gas-liquid separation, it is supplied to the outside of the boiler 1.

[0037] The amount of steam supplied from the separator 21 to the outside may be adjustable according to the required amount of steam from the outside (steam load), etc. Such adjustment is achieved by increasing the heat generation amount of the reactant 12 to increase the amount of steam generated when the amount of steam supplied to the outside is less than the appropriate amount, and decreasing the heat generation amount of the reactant 12 to decrease the amount of steam generated when it is more than the appropriate amount.

[0038] In addition, the heat generation amount of the reactant 12 can be controlled by adjusting the circulation amount of the gas in the circulation path S, and the heat generation amount of the reactant 12 can be increased as the circulation amount increases. Also, in the boiler 1, water is sequentially supplied to the water receiving portion 23 by the amount of steam supplied to the outside, that is, by the amount of water decreased, so that steam can be continuously generated and supplied to the outside.

[0039] In this embodiment, the reactant 12 is employed as the heating element. However, instead, it is also possible to adopt a general heating element. As an example of such a heating element, a halogen heater (a type of heater that generates heat when power is supplied) having the same shape and size as the reactant 12 can be mentioned. When a halogen heater or other heater is the heating element, a plurality of heaters are installed at equal intervals throughout the flow path 51 so that the gas in the flow path 51 can flow, or one or a plurality of heaters are curved while forming gaps and installed to cover the entire flow path 51, and it is preferable to allow the gas flowing in from the gas introduction part 52 to flow into the container 11 while effectively receiving heat from the heater. When applying such a heating element as the heating element, a reaction for generating excessive heat is unnecessary.

[0040] Also, in the form adopting the heating element, by directly controlling the temperature of the heating element through power control, water can be appropriately heated to generate steam. For example, the more the supply power to the heating element is adjusted to increase the heat generation amount of the heating element, the stronger the water passing through the heat transfer tube 22a is heated, and the amount of steam generated in the boiler 1 can be increased.

[0041] The boiler 1 described above includes a heating element, a heat transfer tube 22a through which supplied water (an example of a fluid) passes, a flow path 51 in which a gas (hydrogen-based gas in the example of this embodiment) having a higher specific heat than air is circulated, with the heating element and the heat transfer tube 22a provided in order from the upstream side, and heats the heat transfer tube 22a by applying the gas heated by the heating element. Note that the gas flowing into the gas introduction part 52 from outside the container 11 uses the heat obtained from the heating element to heat the heat transfer tube 22a and flows out from the gas outlet part 53 of the container 11.

[0042] According to the boiler 1, by applying the gas heated by the heating element to the heat transfer pipe 22a, the heat transfer by convection from the heating element to the heat transfer pipe 22a is effectively performed, and the water passing through the heat transfer pipe 22a can be efficiently heated. Furthermore, since a gas having a higher specific heat than air is adopted as the gas, heat transfer is better than when general air is adopted, and the heat generated by the heating element can be efficiently transmitted to the heat transfer pipe 22a. Also, since the specific heat is high, the temperature of the gas hardly fluctuates, and heat can be transmitted to the heat transfer pipe 22a more stably. For example, under the conditions of 200°C and 1 atm, the specific heat of air is about 1,026 J / Kg°C, while the specific heat of hydrogen is about 14,528 J / Kg°C, which is much higher than the specific heat of air.

[0043] Also, the above-mentioned flow path 51 in the present embodiment is a circulation path S for circulating the hydrogen-based gas. Thereby, the hydrogen-based gas can be circulated to promote the reaction that generates excess heat in the reactant 12. When the heating element described above is applied as the heating element, since a reaction that generates excess heat is not required, a gas other than the hydrogen-based gas can be adopted as the gas having a higher specific heat than the above-mentioned air.

[0044] The boiler 1 further includes a first guide member formed such that the inside expands from the inlet side toward the outlet side, and a container 11 connected to the outlet side and having the heat transfer pipe 22a disposed therein. The circulation path S includes the inside of each of the container 11 and the first guide member 18. In particular, in the present embodiment, a plurality of heat transfer pipes 22a extending in the vertical direction are arranged at different positions in the front-rear direction inside the container 11, and the first guide member 18 is formed such that the inside expands in both the vertical direction and the front-rear direction from the inlet side toward the outlet side.

[0045] Therefore, according to the first guide member 18, the hydrogen-based gas flowing in from the gas path 14, which is a tubular body with a relatively small cross-sectional area, can be applied to the plurality of heat transfer tubes 22a in the container 11 as uniformly as possible, and can also be applied as uniformly as possible to a wide range of each of the individual heat transfer tubes 22a. Thereby, the heat generated by the heating element can be efficiently transferred to a wide area of each of the plurality of heat transfer tubes 22a with the hydrogen-based gas as a medium.

[0046] In the boiler 1, the heating element is provided in the gas introduction portion 52 (a part of the flow path 51) of the container 11 so that the gas in the flow path 51 passes through the entire heating element. Therefore, even in a situation where the temperature of the heating element is relatively low (for example, a situation where the heating element has not yet warmed up sufficiently), the heat of the heating element can be efficiently recovered by the gas, and the heat transfer tube 22a can be appropriately heated by applying the gas.

[0047] As specific forms of the heating element and the gas introduction portion 52 described above, various forms can be adopted without departing from the gist of the present invention. As an example, a heating element provided with gaps (for example, a large number of holes) through which the gas in the flow path 51 can flow may be arranged so as to cover the entire gas discharge port (the opening portion through which the gas is discharged into the container 11) in the gas introduction portion 52. In this case, all the gas discharged from the gas introduction portion 52 is dispersed and flows through the gaps of the heating element, and it becomes possible to transfer the heat of the heating element to the gas very efficiently.

[0048] In the present embodiment, water that is the source of steam is made to flow through the water path 22 including the heat transfer tube 22a. Instead, a heat medium Y can be made to flow through a heat medium path including the heat transfer tube, and the water that is the source of steam can be heated using this heat medium Y. A schematic configuration diagram of a boiler configured in this way is illustrated in FIG. 4.

[0049] In the boiler 1a shown in Fig. 4, a heat medium path 40 is provided instead of the water path 22, and a heat exchanger 50 is provided instead of the separator 21. The heat exchanger 50 has a part of the heat medium path 40 through which the heat medium Y flows, and receives water supply from the outside (supply of water that becomes the source of steam).

[0050] Note that the heat medium Y circulates through the heat medium path 40 including the heat transfer pipe 40a, the lower header 40b, and the upper header 40c, as shown by the solid arrows in Fig. 4. The configurations and arrangements of the heat transfer pipe 40a, the lower header 40b, and the upper header 40c are the same as those of the heat transfer pipe 22a, the lower header 22b, and the upper header 22c in the present embodiment.

[0051] Thereby, the heat medium Y heated by the reactant 12 (heat generating body) can be sent into the heat exchanger 50, the supplied water can be heated by the heat medium Y to generate steam, and the steam can be supplied to the outside. Note that the heat exchanger 50 may be configured not only to generate steam by heating water but also to generate hot water.

[0052] As the heat exchanger 50, for example, a plate type or shell and tube type heat exchanger may be adopted, or various types of steam generators may be adopted. As an example of this steam generator, there is a configuration having a storage space for storing the supplied water and a tubular body through which the heat medium Y arranged in the storage space passes, and the heat of the heat medium Y is transmitted to the stored water through the tubular body.

[0053] As described above, the embodiments of the present invention have been explained. However, the configuration of the present invention is not limited to the above embodiments, and various modifications can be made without departing from the gist of the invention. That is, the above embodiments should be considered as illustrative in all respects and not restrictive. For example, the boiler according to the present invention is applicable not only to a boiler that generates steam as in the above embodiment but also to a hot water boiler, a heat medium boiler, and the like. The technical scope of the present invention is shown not by the description of the above embodiments but by the scope of the claims, and it should be understood that all modifications belonging to the meaning and scope equivalent to the scope of the claims are included.

Industrial Applicability

[0054] The present invention can be used in boilers for various applications.

Explanation of Signs

[0055] 1, 1a Boiler 11 Container 12 Reactant 14 Gas path 15 Gas receiving part 16 Gas pump 17 Gas filter 18 First guide member 19 Second guide member 21 Separator 22 Water path 22a Heat transfer tube 22b Lower header 22c Upper header 23 Water receiving part 24 Water pump 40 Heat medium path 40a Heat transfer tube 40b Lower header 40c Upper header 51 Flow path 52 Gas introduction part 53 Gas outlet part

Claims

1. A heating element, a heat transfer tube, a container with the heat transfer tube provided therein, a flow path that can allow a hydrogen-based gas to flow and includes the inside of the container, and is provided with: The heating element, is a reactant in which metal nanoparticles made of hydrogen storage metals are provided on the surface, and in a situation where the hydrogen-based gas is supplied to the flow path, hydrogen atoms are occluded in the metal nanoparticles to generate excess heat, The heating element is provided at a gas introduction portion of the container, which is a part of the flow path, A boiler characterized in that the gas flowing into the gas introduction portion from the outside of the container heats the heat transfer tube using the heat obtained from the heating element and flows out from a gas outlet portion of the container.

2. A heating element, a heat transfer tube, a container with the heat transfer tube provided therein, a flow path that can allow a gas having a higher specific heat than air to flow and includes the inside of the container, and is provided with: The flow path is a circulation path for circulating the gas, The heating element is provided at a gas introduction portion of the container, which is a part of the flow path, A boiler characterized in that the gas flowing into the gas introduction portion from the outside of the container heats the heat transfer tube using the heat obtained from the heating element and flows out from a gas outlet portion of the container.

3. The boiler according to claim 1 or claim 2, characterized in that the heating element is arranged so as to cover the entire gas introduction portion.

4. The boiler according to any one of claims 1 to 3, characterized in that the gas introduction portion is a guide member formed so that the inside expands as it goes in the gas flow direction.

5. The boiler according to claim 4, characterized in that the heating element is plate-shaped with a large number of holes.

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