KR102663740B1 - Heating system - Google Patents

Abstract

The heating system starts. The heating system is a hotbox case; A support plate disposed inside the hotbox case; A plurality of molten carbonate fuel cell stacks disposed on the upper part of the support plate inside the hot box case; A reformer disposed below the support plate inside the hot box case, reforming hydrocarbon fuel and supplying it to the molten carbonate fuel cell stacks; A composite module including a heating tank unit that stores heating water and a combustion unit that heats the heating water; a storage tank connected to the heating tank unit through first and second pipes spaced apart from each other to form a first circulation flow path through which the heating water circulates, storing the heating water, and disposed outside the hot box case; A temperature sensor that measures the temperature of the heating water stored in the storage tank; a first pump that circulates the heating water along the first circulation passage when the temperature of the heating water measured by the temperature sensor is lower than a preset temperature; A heating device that is connected to the storage tank through third and fourth pipes spaced apart from each other to form a second circulation flow path through which heating water circulates, and emits heat energy of the heating water into the heating space; and a second pump that circulates the heating water along the second circulation passage.

Description

Heating system{HEATING SYSTEM}

The present invention relates to a building heating system that can efficiently generate high temperature heating water and hot water.

In countries with seasonal changes or cold regions, boiler systems that use oil, gas, coal, etc. as energy sources are used to heat indoor spaces such as homes and buildings.

A typical boiler system receives fuel from a boiler installed indoors or outdoors in a home or building and combusts the fuel. The water is heated by the combustion heat of the boiler, and the heated water is connected to the boiler and circulates through a heat dissipation circulation line buried in the floor of the room. As water is heated in the boiler, flows through a circulation line for heat dissipation, and is heated again in the boiler, the circulation flow is repeated, and the heat is transferred to the floor of the room, heating the floor of the room.

Additionally, a hot water line is connected to the boiler, and the hot water line is connected to a direct water line supplying tap water, and the direct water line is installed to be connected to a washroom, bathroom, or kitchen.

However, the boiler system as described above burns gas or oil and heats water with the combustion heat to heat the room and also uses hot water, so the use of gas or oil increases, increasing the generation of pollutants harmful to the human body. In addition, the economic burden on households is increasing as fossil fuels are depleted.

To solve this problem, fuel cells, which can generate electricity and heat at the same time while reducing the emission of environmental pollutants and reducing electricity and heating bills, have recently been installed in houses or buildings to provide electricity as needed by users. Methods of producing and using heat directly are being studied.

However, in the case of boiler systems using fuel cells that are currently being studied, a boiler that directly burns fuel is used together with the fuel cell as a heat source, so there is a problem in that the use efficiency of heat energy generated by the fuel cell is not high.

The purpose of the present invention is to provide a heating system that can provide heating and hot water by using only the thermal energy generated in a fuel cell as a heat source.

A heating system according to an embodiment of the present invention includes a hot box case; a support plate disposed inside the hot box case and having a through hole formed in the center; a plurality of molten carbonate fuel cell stacks disposed on an upper portion of the support plate within the hot box case and spaced apart from each other at regular intervals to surround the through hole; A reformer disposed below the support plate inside the hot box case, reforming hydrocarbon fuel supplied from an external fuel source and supplying it to the plurality of molten carbonate fuel cell stacks; A composite module including a heating tank unit that stores heating water and a combustion unit that heats the heating water stored in the heating tank unit, and disposed inside the hot box case; It is connected to the heating tank unit through a first pipe through which the heating water flows out toward the heating tank unit and a second pipe through which the heating water flows in from the heating tank unit to form a first circulation flow path through which the heating water circulates, a storage tank that stores the heating water and is disposed outside the hot box case; A temperature sensor installed in the storage tank and measuring the temperature of the heating water stored in the storage tank; a first pump installed in the first pipe and circulating heating water along the first circulation passage when the temperature of the heating water measured by the temperature sensor is lower than a preset temperature; It is connected to the storage tank through a third pipe that introduces the heating water from the storage tank and a fourth pipe that discharges the heating water toward the storage tank to form a second circulation flow path through which the heating water circulates, A heating device that emits heat energy from heating water into the heating space; and a second pump installed in the third pipe to circulate the heating water along the second circulation passage. The composite module is disposed below the support plate inside the hot box case, and includes a bottom plate, a side wall plate protruding upward from the bottom plate, and a top plate coupled to the upper end of the side wall, and has a combustion space therein. A first storage container formed; A bottom disposed on the bottom plate of the first storage container and coupled to the anode off gas pipe through which the anode off gas discharged from the plurality of solid oxide fuel cell stacks moves, and an internal space moving from the edge of the bottom to the top. A combustion unit including a combustion case including a side wall portion inclined to increase the cross-sectional area and having through holes formed therein, and an ignition device located adjacent to a portion where the anode off gas pipe is coupled; A second storage container disposed between the upper plate of the first storage container and the support plate and forming a first storage space in which the heating water is stored together with the upper plate of the first storage container, of the second storage container A first heat exchange side wall that is coupled to the second storage container to surround the side wall and forms a first heat exchange flow path for movement of cathode off gas discharged from the plurality of solid oxide fuel cell stacks together with the side wall of the second storage container. a first tank portion including a plate and a second heat exchange sidewall plate coupled to the first heat exchange sidewall plate to form a second heat exchange passageway positioned to surround the first heat exchange passageway together with the first heat exchange sidewall plate; and is coupled to the upper plate of the second storage container to form a second storage space connected to the first storage space through an opening formed in the upper plate of the second storage container, and penetrates the through hole of the support plate. a second tank unit including a third storage container disposed; a heating tank unit including a; a connection pipe that connects the first heat exchange flow path and the inner space of the first storage container and supplies the cathode off gas discharged from the first heat exchange flow path to the inner space of the first storage container; and a meandering structure disposed across the inner space of the first storage container at the top of the combustor and including a plurality of straight pipe portions and curved portions connecting them, and a flame or high-temperature combustion generated by combustion in the combustor. It may include a heat exchange pipe that heats air supplied from an external air source using gas and supplies it to the plurality of molten carbonate fuel cell stacks. And, the first pipe is connected to the first storage space of the second storage container, the second pipe is connected to the second storage space through the upper plate of the third storage container, and the first heat exchange flow path The first and second parts spaced apart from each other are connected to the cathode off gas discharge pipe and the connection pipe of the plurality of molten carbonate fuel cell stacks, respectively, and the first and second parts spaced apart from each other of the second heat exchange flow path are connected to each other. The external fuel supply source and the reformer are each connected to the portion, and the height from the upper surface of the support plate to the upper plate of the third storage container is from the upper surface of the support plate to the upper surface of the plurality of molten carbonate fuel cell stacks. It may be 0.8 to 1.2 times the height.

According to the heating system of the present invention, a composite module is installed inside the hot box case of the fuel cell and the combustion section and the heating tank section are integrated into a modular module, so heat energy is generated during the power generation process in the fuel cell stack without using a separate heat source. By using the bay as a heat source, not only high temperature heating water but also hot water can be generated.

1 is a diagram for explaining a heating system according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view for explaining the composite module shown in FIG. 1.
Figure 3 is a cross-sectional view for explaining another embodiment of the heating tank unit shown in Figures 1 and 2.

Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. Since the present invention can be subject to various changes and can have various forms, specific embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to a specific disclosed form, and should be understood to include all changes, equivalents, and substitutes included in the spirit and technical scope of the present invention. While describing each drawing, similar reference numerals are used for similar components. In the attached drawings, the dimensions of the structures are enlarged from the actual size for clarity of the present invention.

Terms such as first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, a first component may be named a second component without departing from the scope of the present invention, and similarly, the second component may also be named a first component.

The terms used in this application are only used to describe specific embodiments and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as “comprise” or “have” are intended to designate the presence of features, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features or steps. , it should be understood that it does not exclude in advance the possibility of the existence or addition of operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by a person of ordinary skill in the technical field to which the present invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and unless explicitly defined in the present application, should not be interpreted in an ideal or excessively formal sense. No.

FIG. 1 is a diagram for explaining a heating system according to an embodiment of the present invention, FIG. 2 is a cross-sectional view for explaining the composite module shown in FIG. 1, and FIG. 3 is a diagram of the heating tank unit shown in FIGS. 1 and 2. This is a cross-sectional view for explaining another embodiment.

1 to 3, the heating system 1000 according to an embodiment of the present invention includes two or more fuel cell stacks 1100, a composite module 1200, a reformer 1300, and a hot box case 1400. , may include a storage tank 1500 and a heating device 1600.

The plurality of fuel cell stacks 1100, the composite module 1200, and the reformer 1300 may be disposed inside the hot box case 1400, and the storage tank 1500 and the heating device 1600 Can be placed outside the hot box case 1400. Meanwhile, internal heat energy is released to the outside in at least a portion of the space inside the hot box case 1400 that is not filled by the fuel cell stack 1100, the composite module 1200, and the reformer 1300. In order to minimize this, insulation material (not shown) may be filled.

Each of the plurality of fuel cell stacks 1100 may include a plurality of single cells that generate electrical energy using oxygen in the air and hydrogen in the reformed fuel gas. The unit cell may include a fuel electrode (anode), an air electrode (cathode), and an electrolyte located between them, and the anode and the air electrode may contain fuel gas containing hydrogen (H ₂ ) and air containing oxygen (O ₂ ). When each is supplied, the oxygen ions (O ^2- ) reduced from the cathode move to the anode via the electrolyte, and the oxygen ions (O ^2- ) moved to the anode are converted to hydrogen (H ₂ ) reacts with it to generate water (H ₂ O) and electrons (e ^- ), and the single cell can generate electrical energy using the electrons generated through the reaction as described above.

Since the reaction between oxygen and hydrogen is an exothermic reaction, each of the fuel cell stacks 1100 can emit heat during a power generation mode that generates electrical energy.

The type of the fuel cell stack 1100 is not particularly limited. For example, each of the fuel cell stacks 1100 includes a solid oxide fuel cell (SOFC), a molten carbonate fuel cell (MCFC) operating at a temperature of about 500°C or higher, or a phosphate electrolyte fuel operating at a temperature of about 200°C or higher. It may include a battery (PAFC), or a polymer electrolyte fuel cell (PEMFC), direct methanol fuel cell (DMFC), or alkaline fuel cell (AFC) that operates at a temperature of around 100°C. Meanwhile, the fuel cell stack 1110 may include a stack of single cells with a flat structure or a bundle of single cells with a tubular or flat tube structure.

The reformer 1300 may reform hydrocarbon fuel supplied from an external fuel supply source to generate hydrogen-containing fuel gas and supply it to the plurality of fuel cell stacks 1100. In one embodiment, The reformer 1300 can reform hydrocarbon fuel supplied from an external fuel source using steam. At this time, the hydrocarbon fuel supplied from the external fuel source is methane (CH ₄ ) and ethane (C ₂ H ₆ ). , propane (C ₃ H ₈ ), butane (C ₄ H ₁₀ ), natural gas, coal gas, etc. may be hydrocarbon fuels that chemically contain the hydrogen element.

The composite module 1200 may include a heating tank unit 1220 connected to the storage tank 1500 and a combustion unit 1210 that heats the heating water stored in the heating tank unit 1220.

In one embodiment, the heating tank unit 1220 may be connected to the storage tank 1500 through a first pipe 1510 and a second pipe 1520, and the first and second pipes 1510, A first circulation flow path may be formed between the storage tank 1500 and the heating tank unit 1220 through 1520. For example, the heating tank unit 1220 may receive relatively low-temperature heating water from the storage tank 1500 through the first pipe 1510, and may supply heated high-temperature heating water to the second pipe 1510. It can be supplied to the storage tank 1500 through the pipe 1520. A first pump 1530 may be installed in the first pipe 1510 so that heating water can move through the first circulation passage.

The combustion unit 1210 is disposed below the heating tank unit 1220 and consumes off gases discharged from the fuel cell stack 1100, for example, anode off gas containing unreacted hydrocarbon fuel and air. The water stored in the heating tank unit 1220 can be heated by burning the cathode off gas it contains.

In one embodiment, as shown in FIG. 2, the combustion unit 1210 includes a first accommodating container 1210b forming a combustion space, and a combustor 1210a disposed inside the first accommodating container 1210b. may include. As an example, the fuel cell stack 1100 may be placed on the support plate 1150 inside the hot box case 1400, and a portion of the heating tank portion 1220 of the composite module 1200 may be It may protrude to the upper part of the support plate 1150 through the opening formed in the support plate 1150, and the remaining portion may be disposed in the lower part of the support plate 1150.

In one embodiment, the combustion unit 1210 may include a first storage container 1210b and a combustor 1210a disposed inside the first storage container 1210b.

The first storage container 1210b may include a bottom plate, a side wall plate protruding upward from the bottom plate, and a top plate coupled to the upper end of the side wall to form an internal space, and the first storage container ( The internal space of 1210b) may be provided as a space for accommodating the combustor 1210a and as a combustion space. In one embodiment, the combustion unit 1210 may further include an exhaust port 1210c that discharges combustion gas from the inner space of the first storage container 1210b to the outside through the exhaust port 1210c. The discharged high-temperature combustion gas may be supplied to a heat exchanger (not shown) that heats the hydrocarbon fuel supplied from the external fuel source, and the hydrocarbon fuel heated by the heat exchanger may be supplied to the reformer 1300.

The combustor 1210a is disposed inside the first storage container 1210b and may include a combustion case opened upward, and the anode discharged from the fuel cell stack 1100 is disposed on the bottom of the combustion case. An anode off gas pipe 1112 for supplying gas may be connected. In one embodiment, the anode off gas pipe 1112 may be coupled to the bottom of the combustion case and supply unreacted fuel gas discharged from the fuel cell stack 1100 to the internal space of the combustion case. .

In one embodiment, the combustion case may have an area that increases toward the top and may have an internal space that is open to the top. In one embodiment, the combustion case may include a bottom disposed on the bottom plate of the first storage container 1210b, and a side wall portion obliquely extended so that the cross-sectional area of the internal space increases from the edge of the bottom to the top. Penetration holes may be formed in the side wall portion to allow external air to flow into the internal space of the combustion case.

Meanwhile, the combustor 1210a may further include an ignition device disposed inside the combustion case so as to be adjacent to a portion where the anode off gas pipe 1112 is connected. As the ignition device, any known ignition device can be applied without limitation.

In one embodiment, the heating tank unit 1220 may include first tank units 1220a and 1220b and second tank units 1220c.

As shown in FIG. 2, the first tank portions 1220a and 1220b are disposed on the upper plate of the first storage container 1210a and are heated together with the upper plate of the first storage container 1210a. A second storage container 1220a forms a first storage space in which water is stored and is coupled to the second storage container 1220a to surround a side wall of the second storage container 1220a. It may include a first heat exchange side wall plate (1220b) that forms a first heat exchange passage for movement of the cathode off gas together with the side wall. A cathode off gas pipe 1111 through which the cathode off gas discharged from the fuel cell stack 1100 moves may be connected to the first position of the first heat exchange passage.

Meanwhile, the first tank portions 1220a, 1220b, and 1220d are arranged to surround the first heat exchange passage, as shown in FIG. 3, and together with the first heat exchange side wall plate 1220b, provide an external fuel supply source ( It may further include a second heat exchange side wall plate (1220d) forming a second heat exchange flow path for heating the hydrocarbon fuel supplied from ''. The hydrocarbon fuel heated in the second heat exchange flow path may be transferred to the reformer (1300). In this case, relatively low-temperature hydrocarbon fuel supplied from the fuel supply source may be supplied to the reformer ( In one embodiment, the first tank parts 1220a, 1220b, and 1220d may be supplied to the reformer 1300 after being previously heated to a temperature suitable for the reforming reaction in 1300). , a second storage container (1220a) disposed on the upper plate of the first storage container (1210a) and forming a first storage space in which heating water is stored together with the upper plate of the first storage container (1210a), A second storage container (1220a) is coupled to the second storage container (1220a) to surround the side wall of the second storage container (1220a) and forms a first heat exchange flow path for movement of the cathode off gas together with the side wall of the second storage container (1220a). 1 A heat exchange side wall plate (1220b) and a second heat exchange side wall plate (1220d) disposed to surround the first heat exchange side wall plate (1220b) and forming the second heat exchange flow path together with the first heat exchange side wall plate (1220b) A cathode off gas pipe 1111 through which the cathode off gas discharged from the fuel cell stack 1100 moves may be connected to a first position of the first heat exchange passage, and a first position of the second heat exchange passage may be connected. A fuel supply pipe 1310 through which hydrocarbon fuel supplied from the fuel supply source moves may be connected to position 1, while cathode off gas after heat exchange may be connected to a second position spaced apart from the first position of the first heat exchange passage. A connection pipe 1230 supplying to the combustion space of the first storage container 1210b may be connected, and the hydrocarbon fuel heated by heat exchange may be supplied to the reformer at a second location spaced apart from the first location of the second heat exchange passage. A fuel supply pipe 1310 for supplying fuel to 1300 may be connected. Meanwhile, the first heat exchange side wall plate 1220b has a portion of the side wall of the second storage 1220b to which the fuel supply pipe 1310 is coupled to facilitate connection of the first pipe 1510. It can be coupled to the side wall of the second storage container 1220b so as to be exposed, and the second heat exchange side wall plate 1220d facilitates coupling with the cathode off gas pipe 1111 and the connection pipe 1230. To do this, the first heat exchange side wall plate 1220b is attached to expose the portion of the first heat exchange side wall plate 1220b to which the cathode off gas pipe 1111 is coupled and the portion to which the connection pipe 1230 is coupled. can be combined

The second tank unit 1220c may include a third storage container coupled to the upper plate of the second storage container 1220a to form a second storage space connected to the first storage space. An opening may be formed in the upper plate of the second storage container 1220a, and the third storage container of the second tank portion 1220c may enter the first storage space of the second storage container 1220a through the opening. A second storage space connected to may be formed. In one embodiment, the third storage container may be disposed to penetrate the opening formed in the support plate 1150 and protrude upward from the support plate 1150. For example, when a plurality of fuel cell stacks 1100 are disposed on the support plate 1150, the third storage container protruding above the support plate 1150 is connected to the plurality of fuel cell stacks 1100. It can be located between them. Since an exothermic reaction occurs inside the fuel cell stacks 1100, the heating water stored inside the second tank portion 1220c may be additionally heated using the heat energy emitted from the fuel cell stacks 1100. You can. Meanwhile, in order to sufficiently utilize the heat emitted from the fuel cell stacks 1100, the height from the support plate 1150 to the top plate of the third storage container is approximately the height of the fuel cell stacks 1100. It may be 0.8 to 1.2 times.

Meanwhile, the first storage space of the heating tank unit 1220 may be connected to the storage tank 1500 through the first pipe 1510, and the second storage space of the heating tank unit 1220 may be connected to the storage tank 1500 through the first pipe 1510. It may be connected to the storage tank 1500 through a second pipe 1520. For example, one end of the first pipe 1510 may be coupled to the second storage container, one end of the second pipe 1520 may be coupled to the third storage container, and the first end of the pipe 1510 may be coupled to the third storage container. And the other ends of each of the second pipes 1510 and 1520 may be respectively coupled to spaced apart portions of the storage tank 1500.

Meanwhile, the heating system 1000 according to an embodiment of the present invention may further include a temperature sensor (not shown) that measures the temperature of the heating water inside the storage tank 1500, and the first pump 1530 may move the heating water along the first circulation flow path when the temperature of the heating water measured by the temperature sensor is less than a preset temperature. For example, the first pump 1530 supplies relatively low-temperature heating water stored inside the storage tank 1500 to the first storage space of the heating tank unit 1220 through the first pipe 1510. It can be moved, and as a result, the storage tank 1500 is heated in the second storage space of the heating tank unit 1220 through the second pipe 1520 and receives relatively high temperature heating water. As a result, the temperature of the heating water stored inside the storage tank 1500 can be increased.

In one embodiment, the composite module 1200 may further include a connection pipe 1230 connecting the internal space of the first storage container 1210b and the heat exchange flow path of the first tank portions 1220a and 1220b. You can. In one embodiment, the first end of the connection pipe 1230 may be coupled to the first heat exchange side wall plate 1220b to be connected to the second position of the heat exchange passage spaced apart from the first position, The second end of the connection pipe 1230 opposite the first end may be coupled to the side wall plate of the first storage container 1210b to be connected to the internal space of the first storage container 1210b.

Through the connection pipe 1230, the cathode off gas discharged from the heat exchange passage of the first tank portions 1220a and 1220b can be supplied to the internal space of the first storage container 1210b, and the combustor 1210a ) can burn the cathode off gas supplied through the connection pipe 1230 and the anode off gas supplied through the anode off gas pipe 1112.

According to the present invention, when the first tank portions 1220a and 1220b are provided with a first storage space in which water is stored and a heat exchange passage surrounding the first storage space and through which high-temperature cathode off gas moves, the first storage space Not only can the water stored in the first storage space be heated more quickly through heat exchange between the water stored in the storage space and the cathode off gas moving through the heat exchange passage, but also the water stored in the first storage space can be heated even when the combustion unit 1210 is not operating. Water stored in the first storage space can be heated.

In one embodiment of the present invention, the composite module 1200 may further include a heat exchange pipe 1240 arranged to cross the combustion space of the combustion unit 1210.

The heat exchange pipe 1240 heats the air supplied from the external air source ('Air') through the flame generated by combustion in the combustor 1210a and through heat exchange with the high-temperature combustion gas, and then heats the air supplied from the external air source ('Air'). It can be supplied to the fuel cell stack 1100. In one embodiment, the heat exchange pipe 1240 may be arranged to cross the inner space of the first storage container 1210b at the top of the combustor 1210a, and may include a plurality of straight pipe parts and bent parts connecting them. It may have a meandering structure, and the inlet and outlet of the heat exchange pipe 1240 may be disposed outside the first storage container 1210b.

As the storage tank 1500, a known heating water storage tank for a boiler can be applied without limitation, and as the heating device 1600, a radiator, a hot water line installed in a heating space, etc. can be applied.

The heating device 1600 may be connected to the storage tank 1500 through a third pipe 1610 and a fourth pipe 1620, and may be connected to the storage tank 1500 through the third and fourth pipes 1610 and 1620. A second circulation flow path may be formed between 1500 and the heating device 1600. For example, the heating device 1600 may receive relatively high-temperature heating water from the storage tank 1500 through the third pipe 1610, and the relatively cooled water from the heating device 1600 may be supplied to the heating device 1600. Low-temperature heating water can be supplied to the storage tank 1500 through the fourth pipe 1620. A second pump 1630 may be installed in the third pipe 1610 so that heating water can move through the second circulation passage.

In one embodiment, the heating system 1000 according to an embodiment of the present invention may further include a hot water heat exchanger 1700.

The hot water heat exchanger 1700 may heat the direct water provided through the direct water pipe through heat exchange with the high-temperature heating water provided from the heating tank unit 1220 and then discharge the hot water.

In one embodiment, a three-way valve 1710 may be installed in the second pipe 1520 for supplying high-temperature heating water from the heating tank unit 1220 to the storage tank 1500, and the direct water pipe may be installed in the second pipe 1520. When water is supplied directly to the hot water heat exchanger 1700 through , Heating water that has completed heat exchange with direct water in the hot water heat exchanger 1700 is connected to the storage tank 1500 or the first pipe 1510 that supplies heating water from the storage tank 1500 to the heating tank unit 1220. can be moved to

According to the heating system of the present invention, a composite module is installed inside the hot box case of the fuel cell and the combustion section and the heating tank section are integrated into a modular module, so heat energy is generated during the power generation process in the fuel cell stack without using a separate heat source. By using the bay as a heat source, not only high temperature heating water but also hot water can be generated.

Although the present invention has been described above with reference to preferred embodiments, those skilled in the art can make various modifications and changes to the present invention without departing from the spirit and scope of the present invention as set forth in the following patent claims. You will understand that it is possible.

1000: Heating system 1100: Fuel cell stack
1200: composite module 1300: reformer
1400: hot box case 1500: storage tank
1600: Heating appliances

Claims (1)

hot box case;
a support plate disposed inside the hot box case and having a through hole formed in the center;
a plurality of molten carbonate fuel cell stacks disposed on an upper portion of the support plate within the hot box case and spaced apart from each other at regular intervals to surround the through hole;
A reformer disposed below the support plate inside the hot box case, reforming hydrocarbon fuel supplied from an external fuel source and supplying it to the plurality of molten carbonate fuel cell stacks;
A composite module including a heating tank unit that stores heating water and a combustion unit that heats the heating water stored in the heating tank unit, and disposed inside the hot box case;
It is connected to the heating tank unit through a first pipe through which the heating water flows out toward the heating tank unit and a second pipe through which the heating water flows in from the heating tank unit to form a first circulation flow path through which the heating water circulates, a storage tank that stores the heating water and is disposed outside the hot box case;
A temperature sensor installed in the storage tank and measuring the temperature of the heating water stored in the storage tank;
a first pump installed in the first pipe and circulating heating water along the first circulation passage when the temperature of the heating water measured by the temperature sensor is lower than a preset temperature;
It is connected to the storage tank through a third pipe that introduces the heating water from the storage tank and a fourth pipe that discharges the heating water toward the storage tank to form a second circulation flow path through which the heating water circulates, A heating device that emits heat energy from heating water into the heating space; and
A second pump installed in the third pipe to circulate the heating water along the second circulation passage,
The composite module is,
A first body disposed below the support plate inside the hot box case and including a bottom plate, a side wall plate protruding upward from the bottom plate, and a top plate coupled to the upper end of the side wall, forming a combustion space therein. storage container; A bottom disposed on the bottom plate of the first storage container and coupled to the anode off gas pipe through which the anode off gas discharged from the plurality of solid oxide fuel cell stacks moves, and an internal space moving from the edge of the bottom to the top. A combustion unit including a combustion case including a side wall portion inclined to increase the cross-sectional area and having through holes formed therein, and an ignition device located adjacent to a portion where the anode off gas pipe is coupled;
A second storage container disposed between the top plate of the first storage container and the support plate and forming a first storage space in which the heating water is stored together with the top plate of the first storage container, of the second storage container A first heat exchange side wall that is coupled to the second storage container to surround the side wall and forms a first heat exchange flow path for movement of cathode off gas discharged from the plurality of solid oxide fuel cell stacks together with the side wall of the second storage container. a first tank portion including a plate and a second heat exchange sidewall plate coupled to the first heat exchange sidewall plate to form a second heat exchange passageway positioned to surround the first heat exchange passageway together with the first heat exchange sidewall plate; and is coupled to the upper plate of the second storage container to form a second storage space connected to the first storage space through an opening formed in the upper plate of the second storage container, and penetrates the through hole of the support plate. a second tank unit including a third storage container disposed; a heating tank unit including a;
a connection pipe that connects the first heat exchange flow path and the inner space of the first storage container and supplies the cathode off gas discharged from the first heat exchange flow path to the inner space of the first storage container; and
It is arranged to cross the internal space of the first storage container at the top of the combustor, has a meandering structure including a plurality of straight pipe portions and curved portions connecting them, and has a flame or high-temperature combustion gas generated by combustion in the combustor. It includes a heat exchange pipe that heats air supplied from an external air source and supplies it to the plurality of molten carbonate fuel cell stacks,
The first pipe is connected to the first storage space of the second storage container,
The second pipe is connected to the second storage space through the upper plate of the third storage container,
The first and second portions of the first heat exchange flow path are connected to the cathode off gas discharge pipe of the plurality of molten carbonate fuel cell stacks and the connection pipe, respectively,
The external fuel supply source and the reformer are respectively connected to first and second parts of the second heat exchange passage, which are spaced apart from each other,
Heating, characterized in that the height from the upper surface of the support plate to the upper plate of the third storage container is 0.8 to 1.2 times the height from the upper surface of the support plate to the upper surface of the plurality of molten carbonate fuel cell stacks. system.