JP2016133292A - Hot water storage tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot water storage tank which enables improvement of pressure resistance and minimizes heat radiation with a compact structure.SOLUTION: Partition plates 36 for inhibiting expansion of a flat casing 26 are provided in the flat casing 26 forming a hot water storage tank 10. Each partition plate 36 is fixed to a pair of hot water storage tank inner wall surfaces disposed at both sides in a thickness direction. Hole parts 38 are formed in each partition plate 36 so that a surface area becomes large from a center to the outer side in the thickness direction.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a hot water storage tank having a flat box shape that is thin in the thickness direction.

  Usually, in the solid oxide fuel cell (SOFC), the operation temperature is relatively high, and the exhaust gas containing the fuel gas and the oxidant gas used for the power generation reaction is also high. For this reason, it is desired to make effective use of exhaust gas.

  For example, a heat exchanger for exchanging heat between exhaust gas from the solid oxide fuel cell and water is provided, and the water is stored in a hot water storage tank. The water in the hot water storage tank is heated by heat exchange to obtain hot water having a predetermined temperature, and the hot water is supplied to a domestic hot water supply system or a heating system.

  As the hot water storage tank, a cylindrical tank is generally used. However, since the same dimension is set in the entire circumferential direction, there is a problem that the degree of freedom in design is low and the entire equipment is enlarged. Therefore, a hot water storage tank having a flat box shape is employed in order to improve design freedom.

  For example, a hot water storage type electric water heater disclosed in Patent Document 1 includes a water inlet, a hot water outlet, a hot water storage, and a plurality of partition walls. The hot water storage section is formed between the water inlet section and the hot water outlet section, and each partition wall section has a meandering flow path that meanders in a direction substantially perpendicular to the thickness direction of the hot water storage section. The interior of the hot water storage section is partitioned so as to be formed inside.

JP 2007-271228 A

  As described above, a hot water storage tank having a flat box shape requires a structure for maintaining pressure resistance. However, in patent document 1, the hot water storage tank is divided | segmented into two division bodies, and the partition wall part is alternately provided in one division body and the other division body. For this reason, a partition wall part does not have the function to maintain the pressure | voltage resistance of a hot water storage tank, and there exists a problem that the rigidity of the said hot water storage tank falls.

  And each partition wall part forms the meandering flow path in a hot water storage tank. Therefore, the hot water flowing through the meandering flow channel comes into contact with the partition wall portion, so that the heat transfer area is increased and the heat is easily radiated. Thereby, the hot water temperature in a hot water storage tank becomes non-uniform | heterogenous, and there exists a problem that favorable hot_water | molten_metal supply performance cannot be maintained.

  This invention solves this kind of problem, and it aims at providing the hot water storage tank which can suppress heat dissipation as much as possible while improving pressure | voltage resistance with a compact structure.

  The present invention relates to a hot water storage tank having a flat box shape that is thin in the thickness direction. A reinforcing member that suppresses the expansion of the hot water storage tank is provided inside the hot water storage tank. The reinforcing member is fixed to a pair of hot water tank inner wall surfaces arranged on both sides in the thickness direction, and the reinforcing member has a surface area that increases outward from the center in the thickness direction. An opening is formed.

  The reinforcing member is preferably a plurality of partition plates, and the partition plates are preferably provided with a plurality of circular hole portions that are openings close to each other. For this reason, the heat transfer area of a partition plate can be made small favorably, and it becomes possible to suppress heat dissipation. In addition, smooth flow of the fluid is performed without hindering the flow of the fluid (hot water or water).

  Furthermore, it is preferable that the reinforcing member is a plurality of partition plates, and the partition plates are provided with a plurality of elliptical holes that are openings close to each other. Therefore, it is possible to satisfactorily reduce the heat transfer area of the partition plate and to suppress heat dissipation. In addition, smooth flow of the fluid is performed without hindering the flow of the fluid (hot water or water).

  Furthermore, it is preferable that the outer periphery of the hot water storage tank has a semicircular cross-sectional shape continuously connected in a flat box shape. Thereby, it can suppress that stress concentrates on the outer periphery of a flat box shape, and it becomes possible to prevent the hot water storage tank from being damaged as much as possible.

  Moreover, it is preferable that the hot water storage tank is arrange | positioned in the gravity direction, and the thickness direction is turned to the horizontal direction, and a some partition plate is extended in the said gravity direction and arranged along the said horizontal direction. In that case, it is preferable that the upper space part connected along the sequence direction of the said several partition plate is formed between the upper end of a several partition plate and the upper inner surface of a hot water storage tank.

  No partition plate is arranged in the upper space portion, and the hot water and air introduced into the upper space portion do not stay and can flow out from the upper portion, and the hot water and the air are retained. Corrosion can be reliably suppressed. In addition, no partition plate is disposed in the upper space portion, and the flow of fluid flowing through the upper space portion is not hindered.

  Furthermore, it is preferable that a lower space part communicating along the arrangement direction of the plurality of partition plates is formed between the lower ends of the plurality of partition plates and the lower inner surface of the hot water storage tank. Therefore, the lower space portion can function as a collection site for dust and the like. In addition, no partition plate is disposed in the lower space, and the flow of fluid flowing through the lower space is not hindered.

  Furthermore, it is preferable that the hot water storage tank is arranged in the direction of gravity and the thickness direction is oriented in the horizontal direction, and the plurality of partition plates extend in the horizontal direction and are arranged along the direction of gravity. . In that case, it is preferable that the obstruction board which does not have an opening part is arrange | positioned in the sequence direction center of a some partition plate. The hot water storage tank is preferably provided with a hot water inlet into which hot water is introduced from the heating device and a hot water outlet from which the hot water is taken out above the closing plate. On the other hand, it is preferable that a water inflow port through which water flows in from the outside and a water outflow port for supplying the water to the heating device are provided below the closing plate.

  That is, in the hot water storage tank, a hot water storage chamber and a hot water distribution path are provided in the upper part of the closing plate, and a hot water storage room and a water flow path are provided in the lower part of the closing plate. Thereby, hot water and water can be separated satisfactorily, and heat radiation can be effectively suppressed.

  According to the present invention, the reinforcing member is fixed to the inner wall surfaces of the pair of hot water storage tanks disposed on both sides in the thickness direction inside the hot water storage tank. For this reason, it can endure effectively the pressure in a hot water storage tank. In addition, an opening is formed in the reinforcing member so that the surface area increases from the center in the thickness direction toward the outside. Accordingly, it is possible to satisfactorily reduce the heat transfer area of the reinforcing member.

  Thereby, it is possible to improve pressure resistance and to suppress heat dissipation as much as possible with a compact configuration.

BRIEF DESCRIPTION OF THE DRAWINGS It is schematic structure explanatory drawing of the SOFC system incorporating the hot water storage tank which concerns on the 1st Embodiment of this invention. It is a perspective view of the hot water storage tank. It is a schematic perspective explanatory drawing which shows the internal structure of the said hot water storage tank. It is a cross-sectional side explanatory view of the hot water storage tank. It is a schematic perspective explanatory drawing which shows the internal structure of the hot water storage tank which concerns on the 2nd Embodiment of this invention. It is a schematic perspective explanatory drawing which shows the internal structure of the hot water storage tank which concerns on the 3rd Embodiment of this invention. It is sectional front explanatory drawing of the said hot water storage tank. It is a schematic perspective explanatory drawing which shows the internal structure of the hot water storage tank which concerns on the 4th Embodiment of this invention.

  As shown in FIG. 1, the hot water storage tank 10 according to the first embodiment of the present invention is incorporated in a SOFC system 12. The SOFC system 12 includes a power generation unit (heating device) 14, and the power generation unit 14 includes a SOFC module 16 that generates power by an electrochemical reaction between fuel gas (hydrogen gas) and oxidant gas (air).

  Although not shown, the SOFC module 16 includes a fuel cell stack in which solid oxide fuel cells are stacked. The fuel cell stack includes a heat exchanger for preheating the oxidant gas, an evaporator for evaporating water in order to produce a mixed fuel of raw fuel and water vapor mainly composed of hydrocarbons, and the mixed fuel. A reformer or the like for generating a fuel gas is provided.

  The heat exchanger performs heat exchange between used reaction gas (hereinafter also referred to as exhaust gas) discharged from the fuel cell stack and air that is a fluid to be heated. The exhaust gas after heat exchange is supplied to the exhaust heat exchanger 20 through the exhaust gas pipe line 18, while water is supplied to the exhaust heat exchanger 20 through a water outlet pipe (water outlet) 22. . The exhaust heat exchanger 20 exchanges heat between the exhaust gas and water, and the hot water whose temperature has been raised is discharged to a hot water inflow pipe (hot water inlet) 24.

The reformer converts higher hydrocarbons (C ₂₊ ) such as ethane (C ₂ H ₆ ), propane (C ₃ H ₈ ) and butane (C ₄ H ₁₀ ) contained in city gas (fuel gas), This is a pre-reformer for steam reforming to a fuel gas containing mainly methane (CH ₄ ), and is set to an operating temperature of several hundred degrees Celsius.

  The hot water storage tank 10 includes a flat casing 26 having a flat box shape that is thin in the thickness direction. As shown in FIG. 2, the flat casing 26 has a rectangular shape when viewed from the front, and the longitudinal direction is arranged along the gravitational direction (arrow A direction), and the thickness direction (arrow t direction) is directed horizontally. ing.

  As shown in FIGS. 1 and 2, a water inflow conduit (water inlet) 30 through which water flows from a tap (external) 28 is connected to the lower end edge of the flat casing 26. A water outflow pipe 22 is connected to a lower portion of the flat casing 26 near the center position O in the arrow A direction.

  A hot water inflow pipe 24 is connected near the upper position of the flat casing 26 in the direction of arrow A in the arrow A direction, and a hot water outflow pipe (hot water outlet) 32 is connected to the upper portion of the flat casing 26. As shown in FIG. 1, the hot water outflow pipe 32 is connected to a domestic hot water supply device (or a heating device or the like) 34, for example.

  As shown in FIG. 2, the outer periphery of the flat casing 26 is constituted by curved surfaces 26a, 26b, 26c and 26d having a semicircular cross section continuously connected in a flat box shape. The flat casing 26 has a first flat surface 26M1 and a second flat surface 26M2 that are two main surfaces that are circulated by the curved surfaces 26a, 26b, 26c, and 26d, and the first flat surface 26M1 and the second flat surface 26M2. The flat surfaces 26M2 are parallel to each other. The water inflow conduit 30, the water outflow piping 22, and the hot water inflow piping 24 are connected to the curved surface 26a which is one side surface. A hot water outflow pipe 32 is connected to the curved surface 26b which is the upper surface.

  As shown in FIGS. 3 and 4, a reinforcing member that suppresses expansion of the flat casing 26, for example, a plurality of partition plates 36, is provided inside the flat casing 26. Each partition plate 36 is a rectangular thin plate, and is provided with a plurality of circular hole portions 38 serving as openings close to each other (independently). As shown in FIG. 4, the partition plate 36 has a surface area that increases outward from the center S in the thickness direction (arrow t direction) by providing the hole 38.

  Each partition plate 36 is fixed to the inner wall surface of the first flat surface 26M1 and the inner wall surface of the second flat surface 26M2 by welding or the like. Each partition plate 36 extends in the direction of gravity and is arranged at equal intervals along the horizontal direction (arrow B direction).

  As shown in FIGS. 3 and 4, between the upper ends of the plurality of partition plates 36 and the inner surface (upper inner surface) of the curved surface 26 b constituting the flat casing 26, along the arrangement direction of the partition plates 36. A communicating upper space 40 is formed. A lower space portion 42 is formed between the lower ends of the plurality of partition plates 36 and the inner surface (lower inner surface) of the curved surface 26 d constituting the flat casing 26, and communicates along the arrangement direction of the partition plates 36. .

  The operation of the hot water storage tank 10 configured as described above will be described below in relation to the SOFC system 12.

In the SOFC module 16, for example, a fuel gas (reformed gas) obtained by reforming raw fuel such as city gas (including CH ₄ , C ₂ H ₆ , C ₃ H ₈ , and C ₄ H ₁₀ ) and an oxidant Power generation is performed by an electrochemical reaction with gas, for example, air. The exhaust gas generated by the power generation reaction is supplied to the exhaust heat exchanger 20 via the exhaust gas pipe 18, while the hot water storage tank 10 is connected to the exhaust heat exchanger 20 via the water outlet pipe (water outlet) 22. Is supplied with water.

  In the exhaust heat exchanger 20, heat exchange is performed between the exhaust gas and water, and the hot water whose temperature has been raised is discharged to the hot water inflow pipe 24 and returned to the hot water storage tank 10. For this reason, in the hot water storage tank 10, hot water of high temperature is introduced and mixed with water, and hot water of a desired temperature is stored. In response to a request from the domestic hot water supply device 34, hot water in the hot water storage tank 10 is supplied from the hot water outflow pipe 32 to the domestic hot water supply device 34. On the other hand, the hot water storage tank 10 is replenished with insufficient water from the water supply 28 via the water inflow conduit 30.

  In this case, in the first embodiment, as shown in FIGS. 3 and 4, in the flat casing 26, the plurality of partition plates 36 are formed on the first flat surface 26 </ b> M <b> 1 disposed on both sides in the thickness direction. It is fixed to the inner wall surface and the inner wall surface of the second flat surface 26M2. For this reason, the flat casing 26 can effectively withstand the internal pressure.

  In addition, as shown in FIG. 4, each partition plate 36 is formed with a plurality of holes 38 so that the surface area increases outward from the center S in the thickness direction (arrow t direction). Yes. Accordingly, it is possible to satisfactorily reduce the heat transfer area of each partition plate 36. In addition, the fluid can be smoothly circulated without hindering the flow of the fluid (hot water or water).

  Thereby, in the hot water storage tank 10, while having a compact structure, while improving pressure | voltage resistance, the effect that it becomes possible to suppress heat dissipation as much as possible is acquired.

  Further, the outer periphery of the flat casing 26 is constituted by curved surfaces 26a, 26b, 26c and 26d having a semicircular cross section. Thereby, the flat casing 26 can suppress the concentration of stress on the outer periphery of the flat box shape, and can prevent the flat casing 26 from being damaged as much as possible.

  Further, the flat casing 26 is arranged in the direction of gravity and has a thickness direction oriented in the horizontal direction, and the plurality of partition plates 36 extend in the direction of gravity and are arranged along the horizontal direction. At that time, as shown in FIGS. 3 and 4, the upper ends of the plurality of partition plates 36 and the inner surface of the curved surface 26 b constituting the flat casing 26 communicate with each other along the arrangement direction of the partition plates 36. An upper space 40 is formed.

  And the partition plate 36 is not arrange | positioned in the upper space part 40, The hot water outflow piping 32 is provided in the upper part of the said upper space part 40. As shown in FIG. For this reason, the hot water and air introduced into the upper space portion 40 do not stay and can flow out to the hot water outflow pipe 32. Therefore, it is possible to effectively utilize the tank capacity of the entire hot water storage tank 10, and it is possible to suppress water line corrosion due to air accumulation, crevice corrosion due to continuous retention of the same fluid, and the like. Furthermore, the partition plate 36 is not disposed in the upper space portion 40, and the flow of fluid flowing through the upper space portion 40 is not hindered.

  Furthermore, a lower space portion 42 is formed between the lower ends of the plurality of partition plates 36 and the inner surface of the curved surface 26 d constituting the flat casing 26, and communicates along the arrangement direction of the partition plates 36. Therefore, the lower space part 42 can function as a part for collecting dust or the like. In addition, the partition plate 36 is not disposed in the lower space portion 42, and the flow of fluid flowing through the lower space portion 42 is not hindered. In addition, in the lower space 42, it is possible to satisfactorily suppress corrosion due to fluid retention.

  FIG. 5 is a schematic perspective explanatory view showing the internal configuration of the hot water storage tank 50 according to the second embodiment of the present invention. In addition, the same referential mark is attached | subjected to the component same as the hot water storage tank 10 which concerns on 1st Embodiment, and the detailed description is abbreviate | omitted. Similarly, in the third and subsequent embodiments described below, detailed description thereof is omitted.

  The hot water storage tank 50 includes a flat casing 26, and a reinforcing member that suppresses expansion of the flat casing 26, for example, a plurality of partition plates 52, is provided inside the flat casing 26. Each partition plate 52 is a rectangular thin plate, and a plurality of elliptical holes 54 that are openings are provided close to each other.

  In the second embodiment configured as described above, the partition plate 52 is provided with a plurality of elliptical holes 54 adjacent to each other. Therefore, the heat transfer area of the partition plate 52 can be satisfactorily reduced, and heat dissipation can be suppressed. In addition, the same effects as in the first embodiment can be obtained, such as smooth flow of the fluid without obstructing the flow of the fluid (hot water or water).

  As shown in FIGS. 6 and 7, the hot water storage tank 60 according to the third embodiment of the present invention includes a flat casing 26. Inside the flat casing 26, a reinforcing member that suppresses the expansion of the flat casing 26, for example, a plurality of partition plates 62, is provided. Each partition plate 62 is a rectangular thin plate, extends in the horizontal direction, and is arranged along the direction of gravity.

  A blocking plate 64 that does not have the hole 38 (opening) is disposed at the center of the plurality of partition plates 62 in the arrangement direction. As shown in FIG. 7, the flat casing 26 is provided with a hot water inflow pipe 24 and a hot water outflow pipe 32 above the closing plate 64, while a water inflow pipe 30 and a water outflow piping are provided below the closing plate 64. 22 is provided.

  In the third embodiment configured as described above, the hot water storage tank 60 is provided with a hot water storage chamber and a hot water flow path above the closing plate 64, and a water hot water storage chamber below the closing plate 64. And a water distribution channel. Thereby, hot water and water can be separated satisfactorily, and it is possible to effectively suppress heat dissipation. In addition, the hot water and air reaching the upper part of the hot water storage tank 60 do not stay and can flow out to the hot water outflow pipe 32, and the occurrence of corrosion can be suppressed well.

  As shown in FIG. 8, the hot water storage tank 70 according to the fourth embodiment of the present invention includes a flat casing 26. Inside the flat casing 26, a reinforcing member that suppresses expansion of the flat casing 26, for example, a plurality of partition plates 72, is provided. Each partition plate 72 is a rectangular thin plate, extends in the horizontal direction, and is arranged along the direction of gravity. Each partition plate 72 is provided with a plurality of elliptical holes 54 that are openings close to each other.

  In the fourth embodiment configured as described above, the partition plate 72 is provided with several elliptical hole portions 54 adjacent to each other. Therefore, the heat transfer area of the partition plate 72 can be satisfactorily reduced, and heat radiation can be suppressed, and the same effects as those of the first to third embodiments can be obtained.

DESCRIPTION OF SYMBOLS 10, 50, 60, 70 ... Hot water storage tank 12 ... SOFC system 14 ... Power generation unit 16 ... SOFC module 20 ... Exhaust heat exchanger 22 ... Water outflow pipe 24 ... Hot water inflow pipe 26 ... Flat casing 30 ... Water inflow pipe 32 ... Hot water Outflow pipe 34 ... Household water heaters 26a to 26d ... Curved surfaces 36, 52, 62, 72 ... Partition plate 38 ... Hole 40 ... Upper space 42 ... Lower space 54 ... Elliptical hole 64 ... Blocking plate

Claims (7)

A hot water storage tank having a flat box shape that is thin in the thickness direction,
Inside the hot water storage tank, a reinforcing member that suppresses expansion of the hot water storage tank is provided,
The reinforcing member is fixed to a pair of hot water tank inner wall surfaces arranged on both sides in the thickness direction,
The hot water storage tank is characterized in that an opening is formed in the reinforcing member so that the surface area increases from the center in the thickness direction toward the outside. The hot water storage tank according to claim 1, wherein the reinforcing member is a plurality of partition plates.
The hot water storage tank according to claim 1, wherein the partition plate is provided with a plurality of circular hole portions which are the opening portions close to each other. The hot water storage tank according to claim 1, wherein the reinforcing member is a plurality of partition plates.
The hot water storage tank according to claim 1, wherein the partition plate is provided with a plurality of elliptical holes that are the openings.   The hot water storage tank according to any one of claims 1 to 3, wherein an outer periphery of the hot water storage tank has a semicircular cross section continuously connected to the flat box shape. The hot water storage tank according to claim 2 or 3, wherein the hot water storage tank is arranged in a gravitational direction and the thickness direction is oriented in a horizontal direction.
The plurality of partition plates extend in the gravitational direction and are arranged along the horizontal direction,
The hot water storage tank, wherein an upper space portion is formed between the upper ends of the plurality of partition plates and the upper inner surface of the hot water storage tank so as to communicate along the arrangement direction of the plurality of partition plates. The hot water storage tank according to claim 2 or 3, wherein the hot water storage tank is arranged in a gravitational direction and the thickness direction is oriented in a horizontal direction.
The plurality of partition plates extend in the gravitational direction and are arranged along the horizontal direction,
A hot water storage tank, wherein a lower space communicating in the arrangement direction of the plurality of partition plates is formed between lower ends of the plurality of partition plates and a lower inner surface of the hot water storage tank. The hot water storage tank according to claim 2 or 3, wherein the hot water storage tank is arranged in a gravitational direction and the thickness direction is oriented in a horizontal direction.
The plurality of partition plates extend in the horizontal direction and are arranged along the gravity direction,
In the center in the arrangement direction of the plurality of partition plates, a closing plate that does not have the opening is disposed,
The hot water storage tank is provided with a hot water inlet through which hot water is introduced from a heating device and a hot water outlet from which the hot water is taken out above the closing plate,
A hot water storage tank provided with a water inlet for allowing water to flow in from the outside and a water outlet for supplying the water to the heating device below the blocking plate.

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