TWI658639B - Modular apparatus of fuel cell system - Google Patents

Abstract

A modular device for a fuel cell system includes a start-up burner, a reformer, an afterburner, and a heat exchanger. The starter burner, reformer, afterburner and heat exchanger are all arranged in a cavity. The reformer surrounds the starter burner, and the afterburner is located above the starter burner and surrounds the reformer. A heat exchanger surrounds the afterburner and the reformer.

Description

Modular equipment for fuel cell systems

The present invention relates to a fuel cell technology, and in particular, to a modular device for a fuel cell system.

Fuel cells are the fourth type of new power generation technology after hydropower, thermal power, and nuclear power generation technologies. They mainly use oxygen or other oxidants to carry out redox reactions to convert chemical energy in fuel into electrical energy. The most common fuel is hydrogen. Other fuel sources come from any hydrocarbon that can decompose hydrogen, such as natural gas, alcohol and methane. Because it is not limited by Carnot loops, the theoretical efficiency of the fuel cell is more than 80%, and the actual efficiency can reach 50% ~ 60%.

Solid oxide fuel cell (SOFC) is a fuel cell technology that uses solid ceramic materials as an electrolyte. The operating temperature of the entire system is between 800 ° C and 1000 ° C. It belongs to a high-temperature fuel cell, so it has a good flexibility in fuel selection. The selectable fuels include methane, natural gas, city gas, biomass, diesel, and other carbons. Hydrogen compounds. When the hydrocarbon fuel is sent to the system, its feed is first recombined to produce a reformed mixture of hydrogen, carbon monoxide, carbon dioxide, and water vapor. The electrochemical reaction between the hydrogen and the oxygen on the cathode side generates electrical energy. Therefore, it has the advantages of high efficiency, suitable fuel diversification, and no need to use precious metals as catalysts. At the same time, the high temperature during operation can also be used to increase power generation efficiency or heat source supply, and has extremely high residual heat value.

However, due to the extremely high operating temperature of solid oxide fuel cell systems, they need to rely on electronic gas heaters to supply them under high-temperature environmental conditions, but the heaters are high energy-consuming devices, so providing a source of battery operation heat in this way will reduce System efficiency. Secondly, due to the complexity of the solid oxide fuel cell system, many pipelines are connected between the components, which may cause thermal losses in the pipelines and reduce system efficiency. Moreover, if the high-temperature waste heat generated during system operation is not effectively reused, it will simply increase energy consumption and not be conducive to environmental protection.

The invention provides a modular device for a fuel cell system, which can make the internal temperature distribution of the device uniform, and can effectively control the heat source of the reformer and the heat exchanger, thereby ensuring the stack temperature and reducing the thermal cycle of the stack ( Thermal cycle) times to achieve the system's simplification, safety, stability and high efficiency.

The modular equipment of the fuel cell system of the present invention is set in a cavity. The modular equipment of the fuel cell system includes a start-up burner, a reformer, an afterburner, and a heat exchanger. The starter burner, reformer, afterburner and heat exchanger are all arranged in the cavity. The reformer surrounds the starter burner, and the afterburner is arranged above the starter burner and surrounds the reformer. The heat exchanger surrounds the afterburner and the reformer.

Based on the above, the present invention uses a modular design to enable the starter burner, recombiner, afterburner, and heat exchanger to be placed in a single cavity, so it is possible to reduce heat without using high energy-consuming components and devices. Loss, effective use of high temperature waste heat and instant temperature control.

In order to make the above features and advantages of the present invention more comprehensible, embodiments are hereinafter described in detail with reference to the accompanying drawings.

Please refer to the following embodiments and accompanying drawings to better understand the present invention, but the present invention can still be implemented in many different forms, and should not be construed as being limited to the embodiments described herein. In the drawings, for the sake of clarity, the components and their relative sizes may not be drawn to actual scale.

FIG. 1 is a schematic diagram of a modular device for a fuel cell system according to an embodiment of the present invention.

Please refer to FIG. 1. The modular equipment of the fuel cell system of this embodiment is disposed in the cavity 100. The modular equipment of the fuel cell system includes a starter burner 102, a reformer 104, an afterburner 106, and The heat exchanger 108 and all the components shown in FIG. 1 are schematic diagrams, and the detailed structure will be described below. The above-mentioned starter burner 102, recombiner 104, afterburner 106, and heat exchanger 108 are all disposed in a single cavity 100, and the recombiner 104 surrounds the starter burner 102, and the afterburner 106 is located above the starter burner 102 And surround the reorganizer 104. That is, the afterburner 106 surrounds the upper part of the reformer 104 to provide preheating for heat exchange and steam generation. The heat exchanger 108 surrounds the afterburner 106 and the reformer 104, and the cross section of the coiled tube structure is represented by several circles in FIG.

In FIG. 1, the start-up burner 102 has a conical structure with small inside and large outside, but the present invention is not limited thereto, and the start-up burner 102 may also have a straight cylindrical structure. Because fuel and air need to be sent during combustion, input pipes in the form of inner and outer pipes can be provided at the bottom of the start-up burner 102, such as the inner pipe 102a for fuel and the outer pipe 102b for air. The reformer 104 surrounding the start-up burner 102 is used to provide the reaction fuel (such as hydrogen) required for the anode of the stack 110, so there will be a pipeline 104a for supplying fuel and a pipeline 104b for supplying room temperature water. The reformed gas of 104 may be output from the reformed gas exhaust pipe 104c. The function of the afterburner 106 is to recover the anode of the stack 110 and the cathode high temperature exhaust gas, and then combust to generate a heat source, which provides the heat source of the reformer 104. Therefore, the afterburner 106 surrounds the reformer 104 and has the same anode as the stack 110 A line 106a connected to the cathode high-temperature exhaust gas. As for the heat exchanger 108, it is a coiled tube structure, which surrounds the inner circumference of the cavity 100, and the heat exchanger 108 has a cold air inlet 108a and a hot air outlet 108b in order to use the start burner 102 or the afterburner 106 The generated high-temperature hot gas transforms the cold air into hot air, and outputs the cathode of the power supply reactor 110 as a reaction fuel.

Hereinafter, each component inside the modularized device of the fuel cell system will be described in detail, but the present invention is not limited thereto.

FIG. 2 is a schematic perspective view of a start-up burner according to an embodiment of the present invention.

Referring to FIG. 2, the start-up burner 102 is a preheating heat source for the reformer (not shown) and the heat exchanger (not shown) when the system is started at normal temperature. The start-up burner 102 may include a combustion chamber 200, a first fuel input pipe 202, a first air input pipe 204, and a first exhaust gas discharge pipe 206. A first air input pipe 204 is provided at the bottom of the combustion chamber 200, a first fuel input pipe 202 is located in the first air input pipe 204, and a first exhaust gas discharge pipe 206 is provided at an upper portion of the combustion chamber 200.

In this embodiment, the start-up burner 102 may further include a gas dispersion cover 208, which is installed at the tail of the first air input pipe 204 and mainly provides a function that the gas can be uniformly dispersed to the surroundings. Therefore, when the air is sent into the combustion chamber 200 through the first air input pipe 204, it will pass through the gas dispersion cover 208, causing the intake direction of the air to be vertical or close to the extending direction of the first fuel input pipe 202. Around the inner wall of the combustion chamber 200 with a conical structure, a vortex guide airflow will be formed to guide the aforementioned dispersed fuel to the combustion chamber 200 for combustion reaction, and the used high-temperature gas will finally pass through the first An exhaust gas discharge pipe 206 is concentratedly discharged. Since the combustion chamber 200 is exemplified by a conical structure with a small inside and a large outside, the fluid movement can be increased to improve the heat transfer efficiency. In addition, by adjusting the fuel-to-air feed ratio, the heat supplied after combustion can be adjusted according to the demand for use.

FIG. 3 is a schematic perspective view of a reorganizer according to an embodiment of the present invention.

3, the reformer 104 includes a steam generation chamber 300, a water input pipe 302, a reformer fuel mixing chamber 304, a steam input pipe 306, a reformed gas mixing chamber 308, a reformed chamber 310, a second fuel input pipe 312, and a reformed gas. An exhaust pipe 314, in which several recombination chambers 310 are connected to the recombiner fuel mixing chamber 304 and the recombination gas mixing chamber 308. The structure of the recombination chamber 310 may be a chassis-shaped multi-straight tube type (or a single spiral tube type). Each recombination chamber 310 is filled with a recombination catalyst, and the burner (Fig. 2) or afterburner (not shown) can be started. The heat generated is transferred to the internally flowing fuel and high-temperature steam through the heat of the tube wall, and the recombination reaction is performed to generate hydrogen-rich recombined gas.

As for the steam generation chamber 300, it is arranged above the start-up burner (Figure 2) and below the reformed gas mixing chamber 308, and the water input pipe 302 extends from the bottom to the steam generation chamber 300, and the structure of the water input pipe 302 can also be selected as The chassis-like multi-straight tube type (or single spiral tube type) enables the heat generated by starting the burner (Figure 2) or the afterburner (not shown) to be transferred to the internal flow chamber through the wall of the water input pipe 302. Warm water is used for preheating and steam generation. As for the reformer fuel mixing chamber 304, it is a ring-like chamber so as to surround the bottom of the start-up burner (Fig. 2). In order to achieve a better preheating and steam generation effect, the steam generation chamber 300 has a circular groove-like structure and functions to mix preheated water. Therefore, after room temperature water flows into the steam generation chamber 300 through the water input pipe 302, steam is generated and passed through the steam. The input pipe 306 flows into the reformer fuel mixing chamber 304 and is mixed with the fuel sent from the second fuel input pipe 312 connected to the reformer fuel mixing chamber 304 to supply fuel and high-temperature steam to the reforming chamber 310. Finally, the recombined gas generated in the recombination chamber 310 will converge to the recombined gas mixing zone 308 (for example, a circular groove structure), and will be centralized to the recombined gas discharge pipe 314 to flow out to the anode side inlet of the stack (not shown).

FIG. 4A is a schematic perspective view of an afterburner according to an embodiment of the present invention.

Referring to FIG. 4A, the afterburner 106 is used to recover the high temperature exhaust gas from the anode and cathode of the stack (not shown) and then combust it to generate a heat source. It is provided as a reformer 104 (including a steam generator) and a heat exchanger (not shown). ) In the high-temperature section. The afterburner 106 includes a mixing combustion chamber 400, a fuel dispersion chamber 402, a third fuel input pipe 404, a second air input pipe 406, and a second exhaust gas discharge pipe 408. The fuel dispersion chamber 402 is disposed in the mixing combustion chamber 400 and has a plurality of fuel output holes 410, so that high-temperature fuel (such as high-temperature exhaust gas from the anode and cathode of the stack) enters the fuel dispersion chamber 402 (such as an annular After the top surface of the structure), the fuel output holes 410 provided on the periphery of the annular structure are evenly distributed to the periphery to improve the combustion efficiency. The second air input pipe 406 is connected to the side of the hybrid combustion chamber 400. The second exhaust gas exhaust pipe 408 is connected to the bottom surface of the hybrid combustion chamber 400.

In this embodiment, the afterburner 106 may further include a regulating fuel input pipe 412, which is in communication with the third fuel input pipe 404. In addition, in order to achieve the temperature adjustment function of the afterburner 106, the adjustment fuel input pipe 412 and the second air input pipe 406 for inputting the adjustment air may be provided on the opposite side of the fuel dispersion chamber 402. Feed ratio of flow path, adjust air-fuel ratio to achieve the purpose of heat adjustment.

When the air is introduced from the second air input pipe 406 on the side of the hybrid combustion chamber 400 as shown in the top view of FIG. 4B, it will advance along the inner wall of the hybrid combustion chamber 400 to form a vortex guide airflow to guide the input along the third fuel. The tube 404 enters the fuel dispersion chamber 402 and the dispersed high-temperature fuel 414 enters the mixed combustion chamber 400 for a combustion reaction to generate high-temperature heat, and provides preheating of other components.

In an embodiment, the second exhaust gas discharge pipe 408 of the afterburner 106 of FIG. 4A described above may be communicated with the first exhaust gas discharge pipe 206 of the start-up burner 102 of FIG. 2 described above, and is used to collectively discharge exhaust gas.

FIG. 5 is a schematic perspective view of a heat exchanger according to an embodiment of the present invention.

Please refer to FIG. 5. The heat exchanger 108 is used to use the high-temperature hot gas generated by starting the burner (FIG. 2) or the afterburner (FIG. 4A), and the pipe is used as a heat conduction medium to form a heat exchanger function. For steam generation or air preheating. Therefore, the heat exchanger 108 may have a coil structure to surround the reformer (FIG. 3) other than the afterburner (FIG. 4A) and the start-up burner (FIG. 2). The heat exchanger 108 has a cold air inlet 108 a and a heat exchanger. Air outlet 108b. The cold air inlet 108a may be provided at the bottom of the cavity (100 in FIG. 1), and the hot air outlet 108b may be provided at the top of the cavity (100 in FIG. 1).

Experiments are listed below to verify the efficacy of the present invention, but the present invention is not limited to the following.

Table 1 shows the simulation comparison between the present invention and the conventional equipment. The results are shown below.

Table 1 Temperature (° C) Reorganizer exit Heat exchanger Afterburner outlet Hot air outlet Learning equipment 686 533 756 this invention 985 820 1006 Heat loss reduction rate 43% 35% 33%

It can be obtained from Table 1 that the design of the present invention is not affected by the environment and external pipelines, so the heat loss is significantly reduced, and the high-temperature waste heat supply system's fuel cell peripheral component (BOP) heat source is effectively used.

〈Simulation experiment example〉

Simulate a cylindrical space with a height of 40 cm and a radius of 10 cm, and simulate a starter burner as shown in Figure 2 with a height of 35 cm, a bottom cylinder height of 5 cm, a diameter of 4 cm, and a cone angle of 10 degrees.

<Simulation comparison example>

Simulate the cylindrical space as in the experimental example, and simulate a cylindrical starter burner with a height of 35 cm and a radius of 5 cm.

The heat flow field between the start-up burner and the reformer is simplified to the above-mentioned simulated cylindrical space, and thermal energy is exchanged with the reformer through the outer wall surface. Heat transfer optimization evaluation index: increase the average temperature of the field.

Results The starter burner of the conical structure obtained by the simulation experiment example has an average field temperature of 6.05% higher than that of the cylindrical structure of the comparative example, and the Nusselt number is increased by 7.83%, which has an excellent heat transfer effect. .

In summary, the present invention integrates the recombiner, the starter burner, the afterburner and the heat exchanger in the same cavity. This structural design has the starter burner and the afterburner, so that the temperature distribution inside the cavity can be uniform, The air-fuel ratio can be controlled by a separate air inlet pipe to adjust the temperature in the equipment. In addition, the present invention can achieve the effects of reducing heat loss, effectively utilizing high-temperature waste heat, and real-time temperature control without using components and devices with high energy consumption, and thus can achieve the goals of system simplification, safety, stability, and high efficiency.

Although the present invention has been disclosed as above with the examples, it is not intended to limit the present invention. Any person with ordinary knowledge in the technical field can make some modifications and retouching without departing from the spirit and scope of the present invention. The protection scope of the present invention shall be determined by the scope of the attached patent application.

100‧‧‧ Cavity

102‧‧‧Start the burner

102a‧‧‧Inner tube

102b‧‧‧External tube

104‧‧‧Reorganizer

104a, 104b, 106a‧‧‧ pipeline

104c‧‧‧Reorganized gas discharge pipe

106‧‧‧ Afterburner

108‧‧‧ heat exchanger

108a‧‧‧cold air inlet

108b‧‧‧Hot air outlet

110‧‧‧Pile

200‧‧‧Combustion chamber

202‧‧‧The first fuel input pipe

204‧‧‧First air inlet pipe

206‧‧‧The first exhaust pipe

208‧‧‧Gas dispersion cap

300‧‧‧Steam generating chamber

302‧‧‧Water inlet pipe

304‧‧‧ reformer fuel mixing chamber

306‧‧‧Steam input pipe

308‧‧‧Recombined Gas Mixing Room

310‧‧‧ Reorganization Room

312‧‧‧Second fuel input pipe

314‧‧‧Reorganized gas discharge pipe

400‧‧‧mixed combustion chamber

402‧‧‧Fuel dispersion chamber

404‧‧‧Third fuel input pipe

406‧‧‧Second air inlet pipe

408‧‧‧Second exhaust pipe

410‧‧‧ fuel outlet

412‧‧‧ Regulate fuel input pipe

414‧‧‧High-temperature fuel

FIG. 1 is a schematic diagram of a modular device for a fuel cell system according to an embodiment of the present invention. FIG. 2 is a schematic perspective view of a start-up burner according to an embodiment of the present invention. FIG. 3 is a schematic perspective view of a reorganizer according to an embodiment of the present invention. FIG. 4A is a schematic perspective view of an afterburner according to an embodiment of the present invention. FIG. 4B is a top view of the fuel dispersion chamber in the combustor after FIG. 4A. FIG. 5 is a schematic perspective view of a heat exchanger according to an embodiment of the present invention.

Claims (9)

A modular device for a fuel cell system includes a start-up burner including: a combustion chamber; a first air input pipe provided at a bottom of the combustion chamber; a first fuel input pipe provided in the first air input pipe A first exhaust gas discharge pipe provided at the upper part of the combustion chamber; and a gas dispersion cover installed at the tail of the first air input pipe so that the intake direction of the air is vertical or close to the first fuel input pipe The extending direction of the reformer; surrounding the starting burner; afterburner arranged above the starting burner and surrounding the reformer; and heat exchanger surrounding the afterburner and the reformer, wherein the starting burner The reformer, the afterburner and the heat exchanger are all arranged in a cavity. The modular equipment of the fuel cell system according to item 1 of the scope of patent application, wherein the combustion chamber has a conical structure. The modularized device for a fuel cell system according to item 1 of the scope of the patent application, wherein the recombiner includes: a steam generating chamber disposed above the starting burner; and a water input pipe extending from the bottom of the starting burner To the steam generating chamber; a reformer fuel mixing chamber surrounding the bottom of the starter burner; a steam input pipe connecting the steam generating chamber and the reformer fuel mixing chamber; a reformed gas mixing chamber provided in the steam generating chamber Above; at least one recombination chamber connected to the recombiner fuel mixing chamber and the recombined gas mixing chamber, and having a catalyst in the at least one recombination chamber; a second fuel input pipe connected to the recombiner fuel mixing chamber; and recombined gas discharge; Tube to connect the reformed gas mixing chamber. The modularized device for a fuel cell system according to item 1 of the scope of patent application, wherein the afterburner includes: a hybrid combustion chamber; a fuel dispersion chamber disposed in the hybrid combustion chamber and having a plurality of fuel output holes; a third A fuel input pipe is connected to the top surface of the fuel dispersion chamber; a second air input pipe is connected to the side surface of the mixed combustion chamber; and a second exhaust gas discharge pipe is connected to the bottom surface of the mixed combustion chamber. The modularized device for a fuel cell system according to item 4 of the scope of the patent application, wherein the fuel dispersion chamber has an annular structure, and the fuel output holes are arranged around the annular structure. The modularized device of the fuel cell system according to item 4 of the scope of the patent application, wherein the afterburner further includes a regulated fuel input pipe, which is in communication with the third fuel input pipe. The modularized device for a fuel cell system according to item 4 of the scope of patent application, wherein the second exhaust gas exhaust pipe is in communication with the first exhaust gas exhaust pipe. The modularized device for a fuel cell system according to item 1 of the scope of patent application, wherein the heat exchanger has a coiled structure and is surrounded along the inner periphery of the cavity, and the heat exchanger has a cold air inlet and Hot air outlet. The modularized device for a fuel cell system according to item 8 of the scope of the patent application, wherein the cold air inlet is provided at the bottom of the cavity, and the hot air outlet is provided at the top of the cavity.