Reforming device and fuel cell system with same

The present invention relates to a fuel cell system, and more particularly to a fuel cell system in which the heat transfer structure of the reformer is improved.

As is known, a fuel cell is a power generation system that generates electric energy by an electrochemical reaction of hydrogen and oxygen contained in a hydrocarbon-based substance such as methanol, ethanol, and natural gas.

Among such fuel cells, the polymer electrolyte fuel cell (PEMFC) developed in recent years has excellent output characteristics, low operating temperature, and at the same time has fast starting characteristics and response characteristics, like an automobile. It can be applied not only to mobile power sources, but also to distributed power sources such as houses and public buildings, and small power sources such as electronic devices, and has the advantage of having a wide range of applications.

The PEMFC basically includes a stack, a reformer, a fuel tank, a fuel pump, and the like. The stack forms an electric generation aggregate composed of a plurality of units, and the fuel pump supplies the fuel in the fuel tank to the reformer. The reformer then reforms the fuel to generate hydrogen, which is then supplied to the stack.

Among them, the reformer generates hydrogen from a fuel containing hydrogen by a chemical catalytic reaction with heat energy, and the heat source portion that generates the heat energy and the hydrogen gas from the fuel by absorbing the heat energy. It includes a reforming reaction section for generating the above-mentioned hydrogen gas and a carbon monoxide reducing section for reducing the concentration of carbon monoxide contained in the hydrogen gas.

<p> However, in the reformer of a conventional fuel cell system, the heat source part, the reforming reaction part, and the carbon monoxide removing part as described above are each configured in a container form, and each of these is connected by a pipe and distributed. Therefore, there is a problem that heat transfer is disadvantageous because heat exchange between each reaction part is not performed directly.</p><p> In addition, since each reaction unit is distributed and arranged, the entire system cannot be realized compactly, and the connection structure through the piping is complicated, so that there is a problem that productivity is lowered.</p><p> The present invention has been made in consideration of the above-mentioned problems, and an object of the present invention is to provide a fuel cell system reformer capable of further improving performance with a simple structure and a fuel cell system using the same. It is in.</p>

<p> Therefore, the reformer of the fuel cell system according to the present invention is formed corresponding to a plurality of reaction parts for generating hydrogen from a fuel containing hydrogen and each of the reaction parts, and provides thermal energy to each of the reaction parts. It also includes a plurality of heating units provided with a catalyst, and a main body in which the plurality of reaction units and heating units are provided in an internal space. At this time, each of the heating units generates different amounts of heat energy required for the reaction in each of the reaction units.</p><p> It is preferable that the amount of the catalyst provided in each of the heating portions is substantially the same, and different amounts of fuel are injected into each to generate different amounts of thermal energy.</p><p> The plurality of reaction sections are arranged continuously with the reforming reaction section for generating hydrogen gas from the fuel by the reforming catalytic reaction and the reforming reaction section to determine the concentration of carbon monoxide contained in the hydrogen gas. It may include at least one carbon monoxide reducing part to be reduced.</p><p> The heating unit may be formed corresponding to each of the reaction units, and each heating unit may include an injection port into which fuel and oxygen are injected.</p><p> It is preferable that the cross-sectional area of the injection port is formed to have different sizes corresponding to each of the heating portions. At this time, it is preferable that the injection port of the heating section that provides heat energy to the reforming reaction section is formed larger than the injection port of the heating section that provides heat energy to the carbon monoxide reduction section.</p><p> The main body includes a first pipe and a second pipe arranged inside the first pipe at a distance from the first pipe, and includes an internal space of the second pipe and the first pipe. The space between the road and the second pipeline is preferably partitioned into a plurality of spaces corresponding to each other.</p><p> It is preferable that a reaction portion is formed in each of the partitioned spaces inside the second pipeline, and a heating portion is formed in each of the partitioned spaces between the first pipeline and the second pipeline.</p><p> It is preferable to form an injection port in which fuel and oxygen are injected into each of the heating portions in the first pipeline. At this time, it is preferable that the cross-sectional area of the injection port is formed to have different sizes corresponding to each of the heating parts, and further, the injection port of the heating part that provides heat energy to the reforming reaction part. However, it is preferable to form the portion larger than the injection port of the heating portion that provides heat energy to the carbon monoxide reduction portion.</p><p> It is preferable that the internal space of the second pipeline is divided into a plurality of spaces by a mesh-shaped barrier member, and the space between the first pipeline and the second pipeline is the same by the partition wall. It is preferable to partition into a plurality of spaces having a large volume.</p><p> The first pipeline is preferably formed of at least one material selected from the group consisting of ceramic, stainless steel and aluminum, and the second pipeline is made of stainless steel, aluminum, copper and iron. It is preferably formed of a material selected from the above group.</p><p> The carbon monoxide reduction unit preferably includes a reaction unit that reduces the concentration of carbon monoxide contained in the hydrogen gas by a water gas conversion (WGS) catalytic reaction of the hydrogen gas. Further, the carbon monoxide reducing unit may include at least one reaction unit that reduces the concentration of carbon monoxide contained in the hydrogen gas by a selective oxidation (PROX) catalytic reaction between the hydrogen gas and oxygen. It is preferable, and it is preferable that the plurality of reaction sections are provided on the upstream side of the reforming reaction section and further include a vaporization section for vaporizing the fuel.</p><p> The plurality of reaction sections and heating sections preferably include pellet-shaped or honeycomb-shaped catalysts that promote each reaction.</p><p> Further, the fuel cell system according to the present invention includes a reforming device that generates hydrogen from a fuel containing hydrogen, and at least one electric generator that generates electric energy by an electrochemical reaction between hydrogen and oxygen. The reformer includes a plurality of reaction parts that generate hydrogen from a fuel containing hydrogen, a plurality of heating parts that provide heat energy to each of the reaction parts and are provided with a catalyst, and the plurality of reaction parts and heating. The part includes the main body provided in the internal space. At this time, each of the heating units generates different amounts of heat energy required for the reaction of each of the reaction units.</p><p> The heating unit may be formed corresponding to each of the reaction units, and each heating unit may include an injection port into which fuel and oxygen are injected. Further, it is preferable that the cross-sectional area of the injection port is formed to have different sizes corresponding to each of the heating portions.</p><p> The fuel cell system according to the present invention preferably includes a fuel supply source for supplying fuel to the reformer and an oxygen supply source for supplying oxygen to the reformer and the electricity generating unit.</p><p> The fuel supply source includes a tank for storing the fuel and at least one fuel pump connected to the tank, and the fuel tank and each inlet are connected by a pipe-shaped supply line. Is preferable. At this time, the fuel pumps having different capacities corresponding to the respective reaction units are installed in the respective supply lines, or the fuel pumps are connected to the fuel tank and the injection port. A fuel control valve can be installed corresponding to the reaction section.</p><p> The oxygen supply source includes at least one air pump that sucks air and supplies the air to the reformer and the electricity generator, and connects the air pump and each of the inlets to a pipe-shaped supply line. It is preferable to connect by. At this time, it is preferable that the air pumps having different capacities are separately installed corresponding to the heating portions, or the flow rate adjusting valve is connected to each supply line connecting the air pump and the injection port. Is preferably installed.</p>

<p> According to the reformer of the present invention, since the plurality of reaction portions and the plurality of heating portions are formed in an integral structure, the heat transfer structure can be simplified. As a result, the thermal efficiency and reaction efficiency of the entire system can be optimized, and the size of the fuel cell system can be made compact by a simple structure.</p>

Hereinafter, examples of the present invention will be described in detail with reference to the attached drawings. The present invention can be modified in various ways, and is not limited to the examples described here.

FIG. 1 is a schematic view showing the overall configuration of the fuel cell system according to the first embodiment of the present invention, and FIG. 2 is an exploded perspective view showing the stack structure shown in FIG.

As shown in FIGS. 1 and 2, the fuel cell system 100 according to the present embodiment reforms a fuel containing hydrogen to generate hydrogen, and generates electric energy by the electrochemical reaction between the hydrogen and oxygen. It uses a polymer electrolyte fuel cell (PEMFC) system.

Fuels for generating electricity in such fuel cell systems include fuels in a liquid or gaseous state containing hydrogen, such as methanol, ethanol or natural gas. However, in the following description, the fuel means a liquid fuel except for the sixth embodiment and the seventh embodiment described later.

Further, in the fuel cell system, pure oxygen stored in a separate storage means can be used as the oxygen that reacts with the hydrogen, and air containing oxygen can also be used. However, the latter will be described below as an example.

The fuel cell system 100 supplies a stack 10 that basically generates electric energy by an electrochemical reaction of hydrogen and oxygen, a reformer 30 that generates hydrogen from fuel, and the fuel to the reformer 30. It includes a fuel supply source 50 and an oxygen supply source 70 that supplies the oxygen to the stack 10 and the reformer 30, respectively.

The stack 10 is composed of an electric generation aggregate formed by continuously arranging a plurality of electric generation units 11. Such a battery generator 11 is the smallest unit that generates electricity by arranging a membrane-electrode assembly (MEA) 12 at the center and separators (also called "bipolar plates" in the industry) 16 on both sides of the membrane-electrode assembly (MEA) 12. It is a fuel cell.

Here, the membrane-electrode assembly 12 has a predetermined active region that causes an electrochemical reaction between hydrogen and oxygen, has an anode electrode on one side, and a cathode electrode on the other side, and these two electrodes. It consists of a structure with an electrolyte membrane between the two.

The anode electrode functions to oxidize hydrogen and convert it into hydrogen ions (protons) and electrons. The cathode electrode functions to generate heat and moisture at a predetermined temperature by reducing the hydrogen ions and oxygen. The electrolyte membrane then functions as an ion exchange to move the hydrogen ions generated at the anode electrode to the cathode electrode.

A passage 17 through which hydrogen and oxygen flow is formed in the separator 16, which supplies hydrogen and oxygen to the membrane-electrode assembly 12 and at the same time functions as a conductor for connecting the anode electrode and the cathode electrode in series. ..

On the outermost side of the stack 10 configured in this way, separate pressure plates 13 and 13'that bring the plurality of electric generators 11 into close contact with each other are provided. It should be noted that the pressure plates 13 and 13'are not provided, and the separator 16 located on the outermost side of the plurality of electricity generating units 11 can be configured to take the role of the pressure plates 13 and 13'. On the other hand, the pressure plates 13 and 13'can be configured so that the plurality of electric generators 11 are brought into close contact with each other and have a function as a separator 16.

Of the pressure plates 13 and 13', one of the pressure plates 13 is supplied from the first injection unit 13a for supplying the hydrogen generated from the reformer 20 to the electricity generation unit 11 and the oxygen supply source 70. A second injection section 13b for supplying the generated air to the electricity generating section 11 is formed. Further, on the other pressure plate 13', the first discharge unit 13c for discharging the hydrogen gas remaining after the reaction in the electricity generation part 11 and the hydrogen and oxygen bonding reaction in the electricity generation part 11 A second discharge section 13d for discharging unreacted air containing water generated by the above is formed.

In the present invention, the reformer 30 generates hydrogen from the fuel by a chemical catalytic reaction using thermal energy. The structure of such a reformer 30 will be described in detail later with reference to FIGS. 3 and 4.

The fuel supply source 50 for supplying fuel to the reformer 30 as described above includes a first tank 51 for storing liquid fuel, a second tank 53 for storing water, and the first and second tanks 51. It includes a fuel pump 55 which is connected to 53 and discharges the liquid fuel and water from the tanks 51 and 53, respectively.

The first and second tanks 51 and 53 are connected and installed to the reformer 30 by the first and third supply lines 91 and 93 in the form of pipes. The reformer 30 and the electricity generating unit 11 of the stack 10 are connected and installed by a fifth supply line 95 in the form of a pipe.

The oxygen supply source 70 includes at least one air pump 71 that sucks air with a predetermined pumping force and supplies this air to the electric generator 11 and the reformer 30 of the stack 10. The air pump 71 and the reformer 30 are connected and installed by the second and fourth supply lines 92 and 94 in the form of pipes, and the air pump 71 and the electric generator 11 of the stack 10 are in the form of pipes. It is connected and installed by the 6th supply line 96.

The reformer 30 in the present invention will be described in detail with reference to the accompanying drawings.

FIG. 3 is a perspective view showing the structure of the reformer according to the first embodiment of the present invention, and FIG. 4 is a cross-sectional view of FIG. 3 cut along the central axis.

As shown in FIGS. 1 to 4, the reformer 30 according to the present embodiment has a structure in which a plurality of reaction parts 35 and heating parts 37 are formed inside a main body 31 in a double pipeline form having an internal space. Has.

To explain this in more detail, the main body 31 has a first pipeline 32 and a cross-sectional area smaller than that of the first pipeline 32, and has a predetermined interval inside the first pipeline 32. It has a cylindrical structure with a second pipeline 33 located. Inside the second pipeline 33, a plurality of reaction units 35 that generate hydrogen from fuel are installed, and the space between the first pipeline 32 and the second pipeline 33 is required for each reaction unit 35. A plurality of heating units 37 are installed to provide a large amount of heat energy.

Specifically, the first pipeline 32 is formed in the form of a cylindrical pipe having a predetermined cross-sectional area and substantially closed at both ends. Such a first conduit 32 can be formed of a heat insulating material having a relatively low thermal conductivity, for example, a metal heat insulating material such as stainless steel or zirconium or a non-metal heat insulating material such as ceramic. Since the first pipeline 32 is made of the heat insulating material in this way, it is possible to prevent the heat energy generated in the heating unit 37 from being released to the outside through the first pipeline 32. As a result, the loss of heat energy generated in the heating unit 37 can be minimized, and the reaction efficiency and thermal efficiency of the entire reformer 30 can be improved.

The second pipeline 33 has a cross-sectional area relatively smaller than the cross-sectional area of the first pipeline 32, and an inflow portion 33a is formed at one side end portion and the other side end portion. The outflow portion 33b is formed, and is formed in a cylindrical pipe form in which both ends are substantially open. That is, the second pipeline 33 is arranged inside the inner peripheral surface of the first pipeline 32 at a distance from the inner peripheral surface thereof, and both end portions thereof penetrate both end portions of the first pipeline 32 to the outside. Has a structure drawn out to. Such a second pipeline 33 can be formed of aluminum, copper, iron or the like having thermal conductivity.

The inflow section 33a is connected to the first and second tanks 51 and 53 of the fuel supply source 50 by a pipe-shaped third supply line 93, and the outflow section 33b is connected to the pipe-shaped fifth supply line 95. It is connected and installed with the electric generator 11 of the stack 10.

The internal space of the second pipeline 33 is partitioned by the barrier member 36, and each reaction unit 35 is formed in each of the spaces partitioned in this way. The barrier member 36 is formed in a mesh shape having a plurality of pores 36a, substantially partitioning the internal space of the second conduit 33, and allowing the reaction gas generated in each reaction section 35 to pass through the pores 36a. It functions to pass through the outflow part 33b side.

In this embodiment, the internal space of the second pipeline 33 is divided into three spaces by the barrier member 36, and the first reaction section 41 and the second reaction section 42 are sequentially divided from the inflow section 33a toward the outflow section 33b. , The third reaction part 43 is formed. However, the present invention is not limited to this aspect, and various modifications are possible, such as partitioning the internal space of the second pipeline 33 into a larger number or providing a plurality of reaction portions. , This also belongs to the technical scope of the present invention.

The first reaction unit 41 is a reforming reaction unit that generates hydrogen gas from the fuel by a steam reforming (SR) catalytic reaction of the fuel, and the second reaction unit 42 and the third reaction unit 43 are described above. It is a carbon monoxide reducing part that substantially reduces the concentration of carbon monoxide contained in hydrogen gas.

Fuel and water are supplied from the first and second tanks 51 and 53 to the first reaction section 41 arranged on the inflow section 33a side through the third supply line 93. The first reaction unit 41 causes a steam reforming catalytic reaction to generate hydrogen from the vaporized fuel. Such a first reaction unit 41 includes a catalyst 41a that promotes the steam reforming reaction of the fuel. The catalyst 41a is configured in a pellet form and is filled and arranged in the internal space of the second pipeline 33 corresponding to the first reaction unit 41. The reforming catalytic reaction by the catalyst 41a of the first reaction unit 41 is an endothermic reaction, and the reaction temperature is about 300 to 600 ° C.

The second reaction unit 42, which is arranged in connection with the first reaction unit 41, contains carbon monoxide contained in the hydrogen gas generated from the first reaction unit 41 by the water gas conversion (WGS) catalytic reaction. It plays a role in primarily reducing the concentration of. Such a second reaction unit 42 includes a normal catalyst 42a that promotes the water gas conversion reaction of the hydrogen gas. The catalyst 42a is configured in a pellet form and is filled and arranged in the internal space of the second pipeline 33 corresponding to the second reaction unit 42. The water gas conversion reaction by the catalyst 42a of the second reaction unit 42 is an exothermic reaction, and the reaction temperature is about 200 to 300 ° C.

The third reaction section 43, which is continuously arranged in the second reaction section 42 on the outflow section 33b side of the main body 31, has a concentration of carbon monoxide contained in hydrogen gas by a selective oxidation (PROX) catalytic reaction of 2. Next, it plays a role of reducing. Such a third reaction unit 43 includes a normal catalyst 43a that promotes the selective oxidation reaction between the hydrogen gas and air. The catalyst 43a is formed in a pellet form and is filled and arranged in the internal space of the second pipeline 33 corresponding to the third reaction unit 43. The selective oxidation reaction of the third reaction section 43 by the catalyst 43a is an exothermic reaction, and the reaction start temperature is about 150 to 200 ° C. Here, the third reaction unit 43 is connected to and installed with the air pump 71 of the oxygen supply source 70 by a fourth supply line 94 in the form of a pipe.

The heating unit 37, which provides heat energy to the reaction unit 35, is located in the space between the first pipe line 32 and the second pipe line 33, and has a configuration in which heat energy is generated by an oxidation catalytic reaction between fuel and air. Has been done. The space between the first line 32 and the second line 33 is divided into a plurality of spaces independent of each other by the partition wall 49. Such a partition wall 49 is formed in an annular shape that is installed in contact with the inner peripheral surface of the first pipeline 32 and the outer peripheral surface of the second pipeline 33.

In this embodiment, the partition walls 49 are arranged at predetermined intervals, and are located between the first pipe line 32 and the second pipe line 33, corresponding to the reaction unit 35 formed inside the second pipe line 33. Divide the space into three independent spaces. Each of these independent spaces is filled with a pellet-shaped catalyst 37a that promotes the oxidation reaction between fuel and air to form a heating unit 37.

Here, of the space between the first pipe line 32 and the second pipe line 33, the heating part formed by filling the space surrounding the first reaction part 41 with the catalyst 37a is the first heating part 371. , The second heating section 372, the first pipeline 32, which is formed by filling the space surrounding the second reaction section 42 in the space between the first pipeline 32 and the second pipeline 33 with the catalyst 37a. The heating portion formed by filling the space surrounding the third reaction portion 43 in the space between the pipe and the second pipeline 33 with the catalyst 37a is referred to as a third heating portion 373. At this time, each of the first heating unit 371, the second heating unit 372, and the third heating unit 373 is passed through the second pipeline 33, and the first reaction unit 41, the second reaction unit 42, and the third reaction unit 43 are provided. Each of them is provided with the thermal energy required for the reaction.

On the other hand, in the first pipeline 32, injection ports 32a1, 32a2, 32a3 for injecting fuel and air into the heating units 371, 372, 373 and reaction gases generated in the heating units 371, 372, 373 are supplied. Discharge ports 32b1, 32b2, 33b3 are formed. That is, in the first pipeline 32, the first injection port 32a1 and the first discharge port 32b1 are formed corresponding to the first heating unit 371, and the second injection port 32a2 corresponds to the second heating unit 372. And the second discharge port 32b2 are formed, and the third injection port 32a3 and the third discharge port 32b3 are formed corresponding to the third heating unit 373.

The respective inlets 32a1, 32a2, 32a3 and the first tank 51 are connected by a first supply line 91 in the form of a pipe. The inlets 32a1, 32a2, 32a3 and the air pump 71 are connected by a second supply line 92.

In this embodiment, the heating units 371, 372, and 373 are filled with the same amount of catalyst 37a, while the heating units 371, 372, and 373 are supplied with different amounts of fuel and air. The reaction section 35 is supplied with an amount of thermal energy that can maintain an appropriate temperature range.

Here, since the heating portions 371, 372, and 373 are filled with substantially the same amount of the catalyst 37a, the spaces of the heating portions 371, 372, and 373 are formed to have substantially the same volume. It is also possible to adjust the passage cross-sectional area of the inlets 32a1, 32a2, 32a3 into which the fuel and air flow in in order to adjust the amount of fuel and air.

Further, the size of the cross-sectional area of the injection ports 32a1, 32a2, and 32a3 passages decreases in the order of the first injection port 32a1, the second injection port 32a2, and the third injection port 32a3. The first and second supply lines 91 and 92 connected to the respective injection ports 32a1, 32a2 and 32a3 are formed so as to have a cross-sectional area corresponding to the size of each of the injection ports 32a1, 32a2 and 32a3. ing.

Generally, when the supply pressure of fuel and air is constant, the amount of fuel and air increases as the cross-sectional area of the passage through which the fuel and air pass increases. In this embodiment, the pumping pressures of the fuel pump 55 and the air pump 71 are substantially constant, and the size of the passage is reduced in the order of the first injection port 32a1, the second injection port 32a2, and the third injection port 32a3. Therefore, a relatively large amount of fuel and air are injected into the first heating unit 371, and a smaller amount of fuel and air than the first heating unit 371 is injected into the second heating unit 372, and the third heating unit 373 is injected. A smaller amount of fuel and air are injected into the second heating unit 372.

If the amount of catalyst 37a is the same, more heat energy can be generated as the amount of fuel and air increases. Therefore, the first heating unit 371 generates the most heat energy, the second heating unit 372 generates a smaller amount of heat energy than the first heating unit 371, and the third heating unit 373 generates a smaller amount than the second heating unit 372. Generates thermal energy.

As a result, the first reaction unit 41 can be maintained at a temperature of 300 to 600 ° C corresponding to the reaction temperature, and the second reaction unit 42 can be maintained at a temperature of 200 to 300 ° C corresponding to the reaction temperature. The third reaction section 43 can be maintained at a temperature of 150 to 200 ° C corresponding to the reaction temperature.

That is, the reformer 30 having the structure as described above integrally forms a plurality of reaction units 35 and a plurality of heating units 37, and adjusts the amount of fuel provided to each heating unit 37 to be different from each other. A large amount of heat energy can be generated. As a result, each reaction unit 35 can maintain the reaction temperature required for each reaction. Therefore, the structure of the reformer can be simplified, and therefore the size of the entire system can be made compact. In addition, the heat transfer structure of the reformer can be simplified to optimize the thermal efficiency and reaction efficiency of the entire system.

Next, the operation of the fuel cell system according to the embodiment of the present invention configured as described above will be described.

First, the fuel pump 55 is driven, and the liquid fuel stored in the first tank 51 is sent to the first heating unit 371 located between the first pipe line 32 and the second pipe line 33 through the first supply line 91. , Supply to each of the second heating unit 372 and the third heating unit 373. At the same time, the air pump 71 is driven to supply air to the heating units 371, 372, and 373 through the second supply line 92. As a result, in each of the heating units 371, 372, and 373, thermal energy at a predetermined temperature is generated by the oxidation reaction between the fuel and air by the catalyst 37a.

At this time, due to the preset pumping force of the fuel pump 55 and the air pump 71, the injection ports 32a1, 32a2, and 32a3 communicating with the heating units 371, 372, and 373 have different cross-sectional areas, so that each heating unit is heated. Parts 371, 372, and 373 are each supplied with different amounts of fuel and air. Since the heating units 371, 372, and 373 are filled with the same amount of catalyst 37a, the heating units 371, 372, and 373 have different amounts from each other by supplying different amounts of fuel and air to each. Generates thermal energy.

That is, since the passage cross-sectional area becomes smaller in the order of the first injection port 32a1, the second injection port 32a2, and the third injection port 32a3, the largest amount of fuel and air are injected into the first heating unit 371. The amount of fuel and air injected into the second heating unit 372 is relatively smaller than the amount injected into the first heating unit 371, and the amount injected into the third heating unit 373 is larger than the amount injected into the second heating unit 372. A relatively smaller amount of fuel and air is injected. As a result, the first heating unit 371 generates thermal energy capable of maintaining a temperature of about 300 to 600 ° C required for the reforming catalytic reaction of the first reaction unit 41, and provides this to the first reaction unit 41. .. The second heating unit 372 generates thermal energy capable of maintaining a temperature of about 200 to 300 ° C required for the water gas conversion catalytic reaction of the second reaction unit 42, and provides this to the second reaction unit 42. To do. The third heating unit 373 generates thermal energy of about 150 to 200 ° C. required for the selective oxidation catalytic reaction of the third reaction unit 43, and provides this to the third reaction unit 43.

In this state, by driving the fuel pump 55, the liquid fuel stored in the first tank 51 and the water stored in the second tank 53 are supplied to the reaction unit 35 through the third supply line 93.

As a result, in the first reaction unit 41, hydrogen gas is generated from the fuel by the steam reforming reaction. This hydrogen gas contains carbon monoxide, which is an unnecessary product due to the steam reforming catalytic reaction. The generated hydrogen gas is supplied to the second reaction unit 42 through the pores 36a of the barrier member 36. In the second reaction unit 42, additional hydrogen is generated from the hydrogen gas by the water gas conversion reaction, and the concentration of carbon monoxide contained in the hydrogen gas is primarily reduced. This hydrogen gas is supplied to the third reaction unit 43 through the pores 36a of the barrier member 36, and at the same time, air is supplied to the third reaction unit 43 through the fourth supply line 94 by driving the air pump 71. After that, in the third reaction unit 43, the concentration of carbon monoxide contained in the hydrogen gas is secondarily reduced by a selective oxidation reaction between the hydrogen gas and air.

The hydrogen generated in this way is discharged through the outflow section 33b of the second pipeline 33 through the third reaction section 43. On the other hand, the reaction gas generated by the oxidation reaction between the fuel and air in the heating units 371, 372, 373 is discharged through the discharge ports 32b1, 32b2, 32b3 corresponding to the heating units 371, 372, 373. ..

Next, the hydrogen discharged from the outflow section 33b is supplied to the electricity generating section 11 of the stack 10 through the fifth supply line 95. At the same time, by driving the air pump 71, air is supplied to the electricity generating unit 11 through the sixth supply line 96. The hydrogen is then supplied to the anode electrode of the membrane-electrode assembly 12 through the separator 16 of the electricity generator 11. Air is then supplied to the cathode electrode of the membrane-electrode assembly 12 through the separator 16.

At the anode electrode, hydrogen gas is decomposed into electrons and protons (hydrogen ions) by an oxidation reaction. Then, the protons move to the cathode electrode through the electrolyte membrane, and the electrons move to the adjacent separator 16 through the separator 16 or a separate terminal (not shown) without moving through the electrolyte membrane. An electric current is generated by such a flow of electrons, and heat and water are additionally generated.

Next, the fuel cell system according to another embodiment of the present invention will be described in detail. Since this embodiment has the same basic configuration as the first embodiment described above, the description thereof will be omitted, and the portion different from the first embodiment described above will be described in detail. Further, in the drawings, the same reference numerals are used for the components substantially the same as those in the first embodiment, and the parts not directly related to the description are omitted from the drawings.

FIG. 5 is a schematic view showing a part of the fuel cell system according to the second embodiment of the present invention.

As shown in FIG. 5, in the fuel cell system 200 according to the present embodiment, fuels having different capacities are connected to the first supply line 91 connecting the inlets 32a1, 32a2, 32a3 and the first tank 51. Pumps 55A, 55B, 55C are connected. Then, air pumps 71A, 71B, and 71C having different capacities are connected to each of the second supply lines 92.

As such fuel pumps 55A, 55B, 55C, and air pumps 71A, 71B, 71C, ordinary diaphragm pumps whose pumping force of the pump itself can be adjusted by a separate control means can be used. Such a diaphragm pump is a pump that converts the rotation of a motor into a linear reciprocating motion of the diaphragm by a cam mechanism or the like to pump fuel and air, and can supply a fixed amount of fluid because the fluctuation of the discharge flow rate is small. To.

At this time, it is preferable that the cross-sectional areas of the respective injection ports 32a1, 32a2, and 32a3 are formed to be the same as each other.

According to this embodiment, the pumping force between the fuel pumps 55A, 55B, 55C and the air pumps 71A, 71B, 71C is adjusted, and different amounts of fuel and air are supplied to the heating units 371, 372, and 373. Can be supplied. Therefore, different amounts of thermal energy can be generated by the oxidation reaction of fuel and air in each of the heating units 371, 372, and 373 and provided to the respective reaction units 41, 42, and 43, and as a result, each reaction. Parts 41, 42 and 43 are maintained at the temperature required for each reaction.

FIG. 6 is a schematic view showing a part of the fuel cell system according to the third embodiment of the present invention.

As shown in FIG. 6, in the fuel cell system 300 according to the present embodiment, the first flow rate control valve is connected to each first supply line 91 connecting the respective inlets 32a1, 32a2, 32a3 and the first tank 51. V1, V2 and V3 are connected. Then, the second flow rate adjusting valves V4, V5, and V6 are connected to the respective second supply lines 92 connecting the respective inlets 32a1, 32a2, 32a3 and the air pump 71. Throttle valves can be used as the first flow rate control valves V1, V2, V3 and the second flow rate control valves V4, V5, V6, respectively.

At this time, the cross-sectional areas of the respective injection ports 32a1, 32a2, and 32a3 are formed to be the same as each other, and the fuel pump 55 and the air pump 71 are substantially relative to the heating portions 371, 372, and 373. This is preferred because it provides the same pumping force.

According to this embodiment, the flow rates of fuel and air supplied to the heating units 371, 372, and 373 through the first flow rate control valves V1, V2, V3 and the second flow rate control valves V4, V5, V6. It can be regulated, which can provide different amounts of thermal energy to the respective reactors 42, 43, 44.

FIG. 7 is a cross-sectional view schematically showing the structure of the reformer in the fuel cell system according to the fourth embodiment of the present invention.

As shown in FIG. 7, in this embodiment, each reaction section 35A of the reformer 30A, that is, the first reaction section 41A, the second reaction section 42A, and the third reaction section 43A are formed in a honeycomb shape. .. A plurality of parallel through holes 41c, 42c, and 43c are formed in each reaction portion 35A, and the structure is such that the catalysts 41b, 42b, and 42c are supported on the inner surface of the cell of a ceramic or metal carrier having a cell. ing. At this time, the through holes 41c, 42c, and 43c form passages through which fuel passes, and catalysts 41b, 42b, and 43b that promote the intrinsic reaction of the respective reaction portions 35A are provided on the inner surface of these passages.

FIG. 8 is a cross-sectional view schematically showing the structure of the reformer in the fuel cell system according to the fifth embodiment of the present invention.

As shown in FIG. 8, the reaction unit 35B of the reformer 30B in this embodiment includes a first reaction unit 41 and at least two or more third reaction units 43. At this time, the first reaction section 41 and at least two or more third reaction sections 43 are continuously arranged from the inflow section 33a side of the second pipeline 33 toward the outflow section 33b. The third reaction unit 43 plays a role of reducing the concentration of carbon monoxide contained in the hydrogen gas by the selective oxidation catalytic reaction between the hydrogen gas generated from the first reaction unit 41 and oxygen.

In FIG. 8, two of the third reaction units 43 are provided, but two or more may be provided.

FIG. 9 is a cross-sectional view schematically showing the structure of the reformer in the fuel cell system according to the sixth embodiment of the present invention.

As shown in FIG. 9, the reaction unit of the reformer 30C in this embodiment includes the vaporization unit 45, the first reaction unit 41, the second reaction unit 42, and the third reaction unit 43. At this time, the vaporization section 45, the first reaction section 41, the second reaction section 42, and the third reaction section 43 are continuously arranged from the inflow section 33a side toward the outflow section 33b in the second pipeline 33. ..

The vaporization unit 45 serves to vaporize the fuel flowing in through the inflow unit 33a and supply it to the first reaction unit 41, and vaporizes the fuel at a temperature of about 700 ° C.

Therefore, the heating unit 37C according to the present embodiment includes the heating unit 375 corresponding to the vaporization unit 45 and the heating units 371, 372, 373 corresponding to the first, second and third reaction units 41, 42 and 43, respectively. including. The same amount of catalyst 37a is provided in each of the heating units 371, 372, 373, and 375, and different amounts of fuel and air flow into each of the heating units 371, 372, 373, and 375, and different amounts of heat energy are applied to the vaporization unit 45 and each. The structure is provided to the reaction sections 41, 42, and 43 of.

FIG. 10 is a cross-sectional view schematically showing the structure of the reformer in the fuel cell system according to the seventh embodiment of the present invention.

As shown in FIG. 10, the reaction unit of the reformer 30D in this embodiment includes a vaporization unit 45, a first reaction unit 41, and at least two or more third reaction units 43. At this time, the vaporization section 45, the first reaction section 41, and at least two or more third reaction sections 43 are continuously arranged from the inflow section 33a side of the second pipeline 33 toward the outflow section 33b.

Although the preferred embodiment of the present invention has been described above, the present invention is not limited to this, and can be variously modified and implemented within the scope of claims, the detailed description of the invention, and the attached drawings. This also belongs to the technical scope of the present invention.

<figref num="1">It is the schematic which showed the overall structure of the fuel cell system by 1st Embodiment of this invention.</figref><figref num="2">It is an exploded perspective view which shows the stack structure shown in FIG.</figref><figref num="3">It is a perspective view which showed the structure of the reformer according to 1st Example of this invention.</figref><figref num="4">FIG. 3 is a cross-sectional view taken along the central axis.</figref><figref num="5">It is the schematic which showed a part of the fuel cell system by 2nd Example of this invention.</figref><figref num="6">It is the schematic which showed a part of the fuel cell system according to 3rd Example of this invention.</figref><figref num="7">It is sectional drawing which showed schematic the structure of the reformer in the fuel cell system according to 4th Example of this invention.</figref><figref num="8">It is sectional drawing which showed schematic the structure of the reformer in the fuel cell system according to 5th Example of this invention.</figref><figref num="9">It is sectional drawing which showed schematic the structure of the reformer in the fuel cell system according to 6th Example of this invention.</figref><figref num="10">It is sectional drawing which showed schematic the structure of the reformer in the fuel cell system according to 7th Example of this invention.</figref>

Code description

10 stack 11 Electricity generator 12 Membrane-Electrode Assembly (MEA) 13,13'Pressure plate 13a 1st injection part 13b 2nd injection part 13c 1st discharge section 13d 2nd discharge section 16 Separator 17 passage 30,30A, 30B, 30C, 30D reformer 31 body 32 1st pipeline 32a1 1st inlet 32a2 2nd inlet 32a3 3rd inlet 32b1 1st outlet 32b2 2nd outlet 32b3 3rd outlet 33 Second pipeline 33a Inflow 33b Outflow 35,35A,35B Reaction part 36a pores 37 Heating part 37a, 41a, 42a, 43a, 41b, 42b, 43b catalyst 41c, 42c, 43c through hole 41,41A 1st reaction part 42,42A 2nd reaction part 43,43A 3rd reaction part 50 Fuel source 51 1st tank 53 2nd tank 55,55A, 55B, 55C fuel pump 70 Oxygen source 71,71A, 71B, 71C Air pump 91 First supply line 92 First supply line 93 Third supply line 94 4th supply line 95 5th supply line 96 6th supply line 100,200,300 fuel cell system 371 1st heating part 372 2nd heating part 373 Third heating part