KR101030045B1 - Reformer for fuel cell system and fuel cell system comprising the same - Google Patents

Abstract

The present invention relates to a fuel cell reformer and a fuel cell system including the same. In a fuel cell reformer for reforming a mixed fuel of liquid fuel and water containing hydrogen to generate a hydrogen-rich reforming gas, the mixed fuel passes through A heat source unit having a flow path having a predetermined length and having a catalyst layer formed on an inner surface of the flow path to supply a heat source for vaporizing the mixed fuel; And a flow path having a predetermined length through which the mixed fuel passes, a catalyst layer is formed on an inner surface of the flow path, and a reforming reaction unit generating hydrogen gas from the mixed fuel through a chemical catalytic reaction by the heat source. The heat source unit provides a reformer for a fuel cell including a CO ₂ permeable membrane, and a fuel cell system including the same.

According to the present invention, a CO ₂ permeable membrane is installed in a combustion reactor by oxidation of fuel of a fuel cell reformer to discharge CO ₂ formed by a combustion reaction to the outside, and H ₂ O can be used as a fuel for steam reforming reaction to exhibit high efficiency. .

Reformer, Fuel Cell System, CO2 Permeable Membrane

Description

Reformer for fuel cell and fuel cell system including same TECHNICAL FIELD

1 is a schematic diagram showing an overall configuration of a fuel cell system according to an embodiment of the present invention.

2 briefly illustrates a reaction mechanism of a methanol reformer according to an embodiment of the present invention.

3 is an exploded perspective view showing the main part of the reformer shown in FIG.

4 is an exploded perspective view illustrating the stack structure shown in FIG. 1.

[Industrial use]

The present invention relates to a fuel cell system, and more particularly, a CO ₂ permeation membrane is installed in a combustion reactor of a fuel cell reformer to remove CO ₂ and supply water to a steam reforming reaction to supply water from the outside of the initial stage of operation of the reformer. The present invention relates to a reformer of a fuel cell system that can minimize efficiency and exhibit high efficiency.

In general, a fuel cell is a power generation system that directly converts chemical energy into electrical energy by an electrochemical reaction generated by using hydrogen contained in a hydrocarbon-based organic fuel such as methanol, ethanol, or natural gas as a fuel. Because of the high specific energy of organic fuels (eg, the specific energy of methanol is 6232 wh / kg), fuel cells using organic fuels are extremely attractive both in installation and in portable applications.

Fuel cells are largely classified into alkali type, phosphoric acid type, molten carbonate type, solid oxide type, and polymer fuel cell according to the type of electrolyte used. Among the various fuel cells, the polymer electrolyte fuel cell (PEMFC) has no risk of corrosion or evaporation due to electrolyte because the polymer is used as an electrolyte, and has a high current density per unit area. Its output characteristics are much higher than other fuel cells, and its operating temperature is low, so that it can be used as a portable power source for automobiles, distributed power sources for homes and public buildings, and small power sources for electronic devices. Korean development is actively being promoted.

In order for such a polymer electrolyte fuel cell to basically have a system configuration, a fuel cell body called a stack (hereinafter referred to as a stack for convenience), a fuel tank and supplying fuel from the fuel tank to the stack are provided. Fuel pumps are needed. In addition, a reformer for reforming the fuel to generate hydrogen gas and supplying the hydrogen gas to the stack in the process of supplying the fuel stored in the fuel tank to the stack is further included. Therefore, the polymer electrolyte fuel cell supplies the fuel stored in the fuel tank to the reformer by the pumping force of the fuel pump, the reformer reforms the fuel to generate hydrogen gas, and the stack electrochemically reacts the hydrogen gas with oxygen. Electric energy is produced.

In this case, the fuel cell may employ a direct methanol fuel cell (DMFC) method capable of supplying a liquid methanol fuel directly to the stack. Such a direct methanol fuel cell fuel cell, unlike the polymer electrolyte fuel cell, the reformer is excluded.

In the fuel cell system as described above, the stack that substantially generates electricity has a structure in which several to tens of unit cells consisting of a membrane electrode assembly (MEA) and a bipolar plate are stacked. Have The membrane / electrode assembly has a structure in which an anode electrode (also called "fuel electrode" or "oxide electrode") and a cathode electrode (also called "air electrode" or "reduction electrode") are attached with an electrolyte membrane interposed therebetween. The bipolar plate simultaneously serves as a passage for supplying hydrogen gas and oxygen necessary for the reaction of the fuel cell and a conductor connecting the anode electrode and the cathode electrode in series with each membrane / electrode assembly. Therefore, hydrogen gas is supplied to the anode electrode by the bipolar plate, while oxygen is supplied to the cathode electrode. In this process, electrochemical oxidation of hydrogen gas occurs at the anode electrode, and electrochemical reduction of oxygen occurs at the cathode electrode, and electricity, heat, and water can be obtained together due to the movement of the generated electrons.

Reformers used in polymer electrolyte fuel cell systems, on the other hand, not only convert hydrogen-containing fuel and water into hydrogen gas for stack electricity generation, but also poisons such as carbon monoxide, which poisons the fuel cell and shortens its life. It is a device for removing substances. Typically, the reformer includes a reforming reaction unit for reforming fuel and a carbon monoxide reduction (removal) unit for removing carbon monoxide. The reforming unit converts the fuel into hydrogen-rich reforming gas through catalytic reaction such as steam reforming, partial oxidation, and autothermal reaction. The carbon monoxide abatement (removal) unit removes carbon monoxide from the reformed gas by a catalytic reaction such as a water gas shift reaction (WGS) or a selective oxidation reaction (PROX) or purification of hydrogen using a separator. do.

The reformer as described above is a device for generating hydrogen gas from a fuel containing hydrogen through a chemical catalytic reaction by thermal energy. Typically, the reformer includes a heat source unit for generating the heat energy, a reforming reaction unit for generating hydrogen gas from the fuel using the heat energy, and a carbon monoxide removing unit for reducing the concentration of carbon monoxide contained in the hydrogen gas. Include.

In the reformer of the conventional fuel cell system, in particular, the reforming reaction unit has a structure in which a reforming catalyst layer for reforming a mixed fuel of liquid fuel and water in a predetermined reactor is formed. Therefore, the reforming reaction unit receives predetermined heat from the outside to generate hydrogen-rich reformed gas from the mixed fuel by the reforming medium reaction through the reforming catalyst layer.

The present invention is to solve the above-mentioned conventional problems, an object of the present invention is to install the CO ₂ permeation membrane in the heat source portion of the combustion reactor by the oxidation of the fuel of the fuel cell reformer to discharge the CO ₂ formed by the combustion reaction to the outside H ₂ O is to provide a micro reformer for a fuel cell that can be used as a fuel of the steam reforming reaction can exhibit high efficiency.

Another object of the present invention is to provide a fuel cell system employing the above reformer.

In order to achieve the above object, the present invention is a fuel cell reformer for generating a hydrogen-rich reformed gas by reforming a mixed fuel of liquid fuel and water containing hydrogen,

A heat source unit including a flow path having a predetermined length through which the mixed fuel passes, a catalyst layer formed on an inner surface of the flow path, and supplying a heat source for vaporizing the mixed fuel; And

A channel having a predetermined length through which the mixed fuel passes, a catalyst layer is formed on an inner surface of the channel, and a reforming reaction unit generating hydrogen gas from the mixed fuel through a chemical catalytic reaction by the heat source,

The heat source unit provides a reformer for a fuel cell including a CO ₂ permeable membrane.

In addition,

A stack for generating electricity by an electrochemical reaction of hydrogen and oxygen;

A reformer for vaporizing a mixed fuel of liquid fuel and water containing hydrogen, and reforming the vaporized fluid to generate hydrogen gas;

A fuel supply unit supplying a mixed fuel to the reformer; And

An air supply for supplying external air to the stack,

The reformer may include a heat path having a predetermined length through which the mixed fuel passes, a catalyst layer formed on an inner surface of the flow path, and supplying a heat source for vaporizing the mixed fuel; And

A channel having a predetermined length through which the mixed fuel passes, a catalyst layer is formed on an inner surface of the channel, and a reforming reaction unit generating hydrogen gas from the mixed fuel through a chemical catalytic reaction by the heat source,

The heat source unit provides a fuel cell system including a CO ₂ permeable membrane.

Hereinafter, the present invention will be described in more detail.

The present invention provides a reformer of a fuel cell system and a fuel display system using the same by installing a CO ₂ permeable membrane in a micro reformer in a fuel cell system, thereby minimizing an initial supply of water, which is one of fuels, and a supply amount from the outside. There is a characteristic.

The reformer of the fuel cell system according to the present invention includes a combustion reactor body having a predetermined length flow path through which the mixed fuel of fuel and air passes, the inner surface of the flow passage having a catalyst layer formed therein, and any of the outer surfaces of the combustion reactor. A heat source unit providing a heat source having a CO ₂ permeable membrane for separating CO ₂ having a predetermined size on one surface; And a reforming reactor having a predetermined length of a passage through which the mixed fuel of fuel and air passes, wherein a catalyst layer is formed on an inner surface of the passage and generates hydrogen by steam reforming of fuel and water by the heat source. .

Further, in the fuel cell system according to the present invention, the reformer has a flow path that enables the flow of the hydrogen gas and a concentration of carbon monoxide contained in the hydrogen gas while having a reaction substrate forming a catalyst layer on the inner surface of the flow path. It may further include at least one carbon monoxide reduction unit for reducing the.

Specifically, the reformer of the present invention may be divided into a heat generating portion and an endothermic portion, wherein the heat source portion is an exothermic portion for generating combustion heat by inducing an oxidation catalytic reaction between fuel and air, and the reforming reaction portion receives the combustion heat from the fuel. It is an endothermic part which induces a reforming catalytic reaction of to generate hydrogen gas. The exothermic part increases the temperature of the reformer and serves to supply heat required for a steam reforming reaction.

At this time, the present invention is provided with a CO ₂ permeable membrane for separating carbon dioxide of a predetermined size on any one surface of the heat source (heating unit). That is, the CO ₂ permeable membrane is preferably installed in a combustion reactor by oxidation of fuel. In addition, in the present invention, a method of installing a CO ₂ permeable membrane in the heat source portion is not particularly limited and may be performed by a known method.

According to the present invention, carbon dioxide is discharged from the water and carbon dioxide formed by the heat source unit (heating unit) to the outside using the permeable membrane, and water is sent to a steam reforming reactor to be used as a fuel for hydrogen formation reaction. Since the water required for the part can be supplied through the heat generating part, the scale of the reformer system can be minimized.

In addition, the present invention can implement a high efficiency reformer by integrating the steam reforming reaction and the water gas shift (WGS) reaction of the fluid through the water supply to the reforming reaction unit (endothermic unit) by the above process. . Therefore, the reformer of the present invention does not need to separately include a water-gas shift (WGS) catalytic reaction part of the fluid in the reaction part.

In addition, the CO ₂ permeable membrane that can be used in the present invention may be a porous membrane or a nonporous membrane.

When preparing a non-porous membrane in the present invention, it is preferable to use a solution, it can be prepared by a method known in the art. At this time, it is preferable to use water as the solvent used to prepare the polymer solution.

In addition, the method of forming the CO ₂ permeable membrane may be prepared by casting a polymer solution on a solid support and then removing the solvent.

The polymer may be polyvinylidene fluoride (PVDF), polyethylene oxide, or the like. In addition, the solid support may be selected from the group consisting of alumina, titania, and zirconia.

In the reformer of the fuel cell system according to the present invention, the flow path has an inlet through which a mixed fuel of liquid fuel and water containing hydrogen flows in, and an outlet through which reformed gas generated through the reforming reaction flows out.

In the reformer of the fuel cell system according to the present invention, the heat source unit may further include a heating member installed in contact with the flow path to heat the flow path, wherein the heating member comprises a heating plate in contact with the flow path; It may include a heating wire embedded in the heating plate, it is preferable to form a mold groove for joining the flow path in the heating plate. In this case, the flow path may be formed to be bent in a zigzag shape.

The flow path formed inside the combustion reactor included in the heat source portion of the reformer of the fuel cell system according to the present invention may be formed by a conventional method, and a support layer is disposed between the inner surface of the flow path and the catalyst layer to provide the catalyst layer. I can support it. In this case, the support layer is preferably made of any one material selected from alumina, silica or titania. In addition, the combustion reactor is preferably made of any one material selected from silicon, glass or stainless steel. As the catalyst of the heat source unit, precious metals such as Pt / Ru may be mainly used, but are not particularly limited thereto.

In addition, the reforming reaction unit has a flow path formed therein by a conventional method, and the inner surface of the flow path may include a support layer and a catalyst layer. The support layer is preferably made of any one material selected from alumina, silica or titania. In addition, the reforming reaction unit is preferably made of any one material selected from silicon, glass or stainless steel. Zn, Fe, Cr, Cu, Ni, Rh, Cu / Zn and the like may be mainly used as the catalyst of the reforming unit, but is not particularly limited.

The shape of the reformer including the heat source portion and the reforming reaction portion may be a substantially rectangular or circular tube having a predetermined length, width and thickness, and the form is not particularly limited.

In addition, the reformer of the fuel cell system according to the present invention may further include at least one carbon monoxide reduction unit connected to the flow path to reduce the concentration of carbon monoxide from the reformed gas generated by the reforming reaction unit.

The present invention also provides a fuel cell system employing the above reformer, comprising: a stack for generating electricity by an electrochemical reaction between hydrogen and oxygen; A reformer of the present invention as described above for vaporizing a mixed fuel of liquid fuel and water containing hydrogen and reforming the vaporized fluid to generate hydrogen gas; A fuel supply unit supplying a mixed fuel to the reformer; And an air supply unit supplying external air to the stack.

In the fuel cell system according to the present invention, the fuel supply unit is connected to a first tank for storing a liquid fuel containing hydrogen, a second tank for storing water, and the first and second tanks. A fuel pump may be included, and the air supply unit may include an air pump that sucks external air.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

1 is a schematic diagram showing the overall configuration of a fuel cell system according to an embodiment of the present invention.

In the fuel cell system 100 according to the present invention, a fuel for generating electricity is a broad fuel, in addition to a narrow fuel containing hydrogen such as methanol, ethanol or natural gas. And oxygen further. Preferably methanol can be used. However, the fuel described below is defined as a liquid fuel for convenience and the liquid fuel and water are defined as a mixed fuel.

In addition, the system 100 may use pure oxygen gas stored in a separate storage means as oxygen reacting with hydrogen contained in the fuel, and may use air containing oxygen as it is. However, the latter example of using air as oxygen will be described below.

Referring to FIG. 1, the fuel cell system 100 according to the present invention basically includes a reformer 30 for reforming the mixed fuel to generate hydrogen gas, and a hydrogen gas generated by the reformer 30 and an external device. The stack 10 for converting the chemical reaction energy of air into electrical energy to produce electricity, the fuel supply unit 50 for supplying the mixed fuel to the reformer 30, and supplying external air to the stack 10. It is configured to include an air supply unit 70.

In the fuel cell system according to the present invention, the polymer generates the hydrogen gas through the reformer 30 and supplies the hydrogen gas to the stack 10 to generate electrical energy through an electrochemical reaction between hydrogen and oxygen. Electrolyte Fuel Cell (PEMFC) is adopted.

The fuel supply unit 50 is connected to the reformer 30 and has a structure in which the fuel pump as in the prior art is excluded. That is, the fuel supply unit 50 includes a first tank 51 for storing liquid fuel containing hydrogen and a second tank 52 for storing water, wherein the first tank and the second tank are respectively. Connected to the fuel pump (not shown), respectively. At this time, the fuel supply unit 50 and the reformer 30 may be connected by the first supply line 81.

In addition, the air supply unit 70 is installed to be connected to the stack 10 and includes an air pump 71 for sucking external air with a predetermined pumping force. In this case, the stack 10 and the air supply unit 70 may be connected and installed by the air supply line 85.

In addition, the reformer 30 according to the present embodiment includes a heat source part 31 for inducing catalytic oxidation of liquid fuel and air to generate combustion heat, and a reforming reaction part for reforming the mixed fuel to generate hydrogen gas ( 37). In addition, the reformer may further include at least one carbon monoxide reduction unit capable of actively removing carbon monoxide from the hydrogen gas.

FIG. 2 schematically illustrates a reaction mechanism of a reformer in a fuel cell system according to an exemplary embodiment of the present invention. 2 illustrates a case where the fuel is methanol, but the present invention is not limited thereto.

1 and 2, in the heat source unit (heating unit) 31 of the methanol reformer of the present invention, methanol and oxygen supplied from the outside react with an oxidation catalyst to generate water and carbon dioxide. The CO ₂ permeable membrane 34 is installed in the combustion reactor of the section 31 to remove carbon dioxide. Then, the generated water is supplied to the reforming reaction section (endothermic section) 37 for the steam reforming reaction to produce a reaction with methanol. By this process, the present invention can supply the water required for steam reforming through the heating portion, it is possible to minimize the scale of the reformer system. In addition, through such a water supply it is possible to implement a high efficiency reformer by integrating the steam reforming reaction and the water gas shift reaction. That is, in the reforming reaction unit 37, carbon monoxide may react with water again by water gas shift reaction (WGS) to further generate hydrogen.

The reformer of the present invention can be divided into a heat generating portion and an endothermic portion, wherein the heat source portion is an exothermic portion for generating combustion heat by inducing an oxidation-catalyzed reaction between fuel and air, and the reforming reaction portion receives the combustion heat from the fuel. An endothermic portion that induces a reforming catalytic reaction to generate hydrogen gas. The exothermic part increases the temperature of the reformer and serves to supply heat required for a steam reforming reaction.                     

At this time, the present invention is provided with a CO ₂ permeable membrane 34 for separating carbon dioxide of a predetermined size on any one surface of the heat source portion 31. That is, the CO ₂ permeable membrane is preferably installed in a combustion reactor by oxidation of fuel. In addition, in the present invention, a method of installing a CO ₂ permeable membrane in the heat source portion is not particularly limited and may be performed by a known method.

In addition, the CO ₂ permeable membrane that can be used in the present invention may be a porous membrane or a nonporous membrane.

When preparing a non-porous membrane in the present invention, it is preferable to use a solution, it can be prepared by a method known in the art. At this time, it is preferable to use water as the solvent used to prepare the polymer solution.

In addition, the method of forming the CO ₂ permeable membrane may be prepared by casting a polymer solution on a solid support and then removing the solvent.

The polymer may be polyvinylidene fluoride (PVDF), polyethylene oxide, or the like. In addition, the solid support may be selected from the group consisting of alumina, titania, and zirconia.

3 is an exploded perspective view showing the main part of the reformer shown in FIG.

Referring to FIG. 3, the reformer 30 includes a heat source part 31 having a combustion reaction for vaporizing a mixed fuel and a flow path having a predetermined length having a fluid movement passage through which the mixed fuel can pass. 33), and the CO ₂ permeable membrane (not shown) is provided on one surface of the heat source portion outside. In one example, the flow path 33 has an inner diameter of less than 1 mm, and is made of a circular pipe type with both ends open. The flow path 33 includes an inlet port 33a through which the mixed fuel supplied through the fuel supply unit 50 flows into the fluid movement passage, and the reformed gas generated by the reforming reaction in the flow path 33. The outlet port 33b which flows out is formed. Preferably, the flow path 33 may be formed to be bent in a zigzag as shown in the figure. However, the shape of the flow path 33 of the heat source portion of the present invention is not limited to being in a zigzag form, but may be in the form of a straight line or a coil, and various forms depending on the arrangement of the components constituting the present system 100. It may be modified in various ways.

The heat source part 31 may be formed of a substantially rectangular plate type having a predetermined length, width, and thickness, and may be formed of a material having thermal conductivity. In addition, the structure formed on the inner surface of the passage has a structure in which an alumina coating layer (support layer) formed by a conventional method and a catalyst layer supported on the support layer are loaded. In this case, Pt-based noble metals and the like may be mainly used as the catalyst of the heat source unit, and they may be coated on an oxide layer such as alumina or ceria to form a catalyst layer.

In addition, the heat source part 31 as described above is a heat generating portion for supplying a heat source for generating the reformed gas of the reforming reaction part 37, and the heating member 35 is installed in contact with the upper and lower portions of the flow path 33, respectively. ) May be further provided. Each heating member has a heating plate containing a heating wire electrically connected to a predetermined power source (not shown). In addition, the heating plate may form a mating groove in which the channel 33 may be joined to a surface on which the upper and lower portions of the channel 33 contact each other. Therefore, the flow path 33 is firmly fixed to the heating plate as it is joined to the matching groove of the heating plate.

Alternatively, the heat source unit 31 may include a heat source unit having a structure for generating combustion heat of a predetermined temperature by a catalytic oxidation reaction between a liquid fuel and external air. To this end, the heat source part 31 may form a flow path (not shown) that enables the flow of the fluid inside the heating plate, and may form an oxidation catalyst layer in the flow path.

In addition, in the reformer according to the present embodiment, the heat source unit is connected to the reforming reaction unit 37, the reforming reaction unit 37 is made of a substantially rectangular plate type having a predetermined length, width and thickness. It may be formed of a material having thermal conductivity. In addition, the structure formed on the inner surface of the passage has a structure in which an alumina coating layer (support layer) formed by a conventional method and a catalyst layer supported on the support layer are loaded. In this case, Zn, Fe, Cr, Cu, Ni, Rh, Cu / Zn, etc. may be mainly used as the catalyst of the Gaebil reaction unit, but is not particularly limited.

In addition, the reformer according to the present embodiment may additionally include at least one carbon monoxide reduction unit (not shown) to reduce the concentration of carbon monoxide formed by the reaction of the reforming reaction unit 37.

The carbon monoxide reduction unit includes a reaction vessel connected to the reforming reaction unit 37 and an aqueous gas shift catalyst layer or a carbon monoxide selective oxidation catalyst layer formed inside the reaction vessel. The reaction vessel is provided with an inlet port through which the reformed gas discharged from the reforming reaction unit 37 flows into the inner space of the vessel, and the reformed gas catalyzed by the catalyst layer as described above in the inner space is discharged into the stack 10. The outlet can be formed.

In addition, according to the present embodiment, an on-off valve 88 may be provided between the reforming reaction unit 37 and the stack 10. Preferably, the on-off valve 88 is installed on the fourth supply line 84 as described above. The shutoff valve 88 has a structure of a general valve body selectively opened and closed by a constant pressure of hydrogen gas acting on the reforming reaction unit 37. The on-off valve 88 opens the fourth supply line 84 when the pressure of the hydrogen gas acting on the reforming reaction unit 37 rises to a preset pressure, and opens the fourth supply line 84 when the pressure is kept lower than the preset pressure. 4 has a function of closing the supply line 84.

In addition, the on-off valve 88 has a function of selectively opening and closing according to the load required for the overall system to control the amount of hydrogen gas supplied to the stack 10 through the fourth supply line 84.

4 is an exploded perspective view illustrating the stack structure shown in FIG. 1.

1 and 4, the stack 10 applied to the present system 100 may be formed by oxidation / reduction reaction of hydrogen gas generated through the reformer 30 having the structure as described above and air contained in the air. At least one electricity generating unit 11 for generating electrical energy.

Each of the electricity generating units 11 refers to a cell of a unit for generating electricity, and includes a membrane electrode assembly (MEA) 12 that oxidizes / reduces the reformed gas and oxygen in the air, and the reformed gas and It consists of a bipolar plate 16 for supplying air to the membrane / electrode assembly 12.

The electricity generating unit 11 has a bipolar plate 16 on both sides thereof with the membrane / electrode assembly 12 at the center thereof. As a result, the stack 10 is configured by continuously arranging the plurality of electricity generating units 11 as described above. Herein, the bipolar plates 16 positioned at the outermost sides of the stack 10 may be defined as end plates 13.

The membrane / electrode assembly 12 has a structure of a conventional MEA (Membrane Electrode Assembly) in which an electrolyte membrane is interposed between an anode electrode and a cathode electrode forming both sides. The anode electrode is a portion receiving the reformed gas through the bipolar plate 16, a catalyst layer converting the reformed gas into electrons and hydrogen ions by an oxidation reaction, and a gas diffusion layer for smooth movement of the electrons and hydrogen ions. : GDL). The cathode electrode is a portion to which air is supplied through the bipolar plate 16, and is composed of a catalyst layer for converting oxygen in the air into electrons and oxygen ions by a reduction reaction, and a gas diffusion layer for smooth movement of electrons and oxygen ions. The electrolyte membrane is a solid polymer electrolyte having a thickness of 50 to 200 µm, and has an ion exchange function for transferring hydrogen ions generated in the catalyst layer of the anode electrode to the catalyst layer of the cathode electrode.

The bipolar plate 16 described above has a function of a conductor that connects the anode electrode and the cathode electrode of the membrane / electrode assembly 12 in series. The bipolar plate 16 also has a function of a passage for supplying the reforming gas and air necessary for the oxidation / reduction reaction of the membrane / electrode assembly 12 to the anode electrode and the cathode electrode. To this end, a flow path 17 is formed on the surface of the bipolar plate 16 to supply a gas for the oxidation / reduction reaction of the membrane / electrode assembly 12.

More specifically, the bipolar plate 16 is disposed on both sides thereof with the membrane / electrode assembly 12 interposed therebetween, so as to be in close contact with the anode electrode and the cathode electrode of the membrane / electrode assembly 12. In addition, the bipolar plate 16 supplies a reforming gas to the anode electrode and the air flow path 17 for supplying air to the cathode electrode, in contact with the anode electrode and the cathode electrode of the membrane / electrode assembly 12, respectively. Forming.

Each end plate 13 is disposed on the outermost side of the stack 10 to perform the function of the bipolar plate 16 as described above, and also has a function of closely contacting the plurality of electricity generating units 11. Each end plate 13 may be in close contact with any one of an anode electrode and a cathode electrode of the membrane / electrode assembly 12. In addition, a flow path flow path 17 for supplying any one of the reformed gas and air to any one of the above-described electrodes may be formed on the contact surface of the end plate 13 which is in close contact with the membrane / electrode assembly 12.

The flow path channel 17 for supplying any one of hydrogen gas and air to any one of the electrodes is formed on the contact surface of the end plate 13 in close contact with the electrode-electrolyte composite 12.

In addition, the end plate 13 has a pipe-shaped first supply pipe 13a for injecting hydrogen gas generated from the reformer 30 into one of the flow channel 17 and air into the other flow channel 17. Pipe-shaped second supply pipe (13b) for injecting, the first discharge pipe (13c) for discharging the remaining unreacted hydrogen gas in the plurality of electricity generating unit 11, and the above-mentioned electricity generating unit ( A second discharge pipe 13d for discharging the unreacted and remaining air finally in 11) is provided.

The first supply pipe 13a is connected to the reforming reaction part 37 of the reformer 30 through the fourth supply line 84 described above. The second supply pipe 13b is connected to the air supply unit 70 through the air supply line 85 as described above.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the scope of the invention.

According to the present invention, in the reformer of a fuel cell system, a CO ₂ permeation membrane is provided at a heat source of the reformer, thereby discharging CO ₂ generated by a combustion reaction to the outside and using water as a fuel for steam reforming reaction. The amount of water supplied from the outside, which is one of the fuels, can be minimized. In addition, by using the water by this process in the steam reforming reaction, it is possible to implement a high efficiency reformer by integrating the steam reforming reaction and the water gas shift (WGS) reaction through the excess water supply.

Claims (13)

In a fuel cell reformer for reforming a mixed fuel of liquid fuel and water containing hydrogen to generate a reformed gas rich in hydrogen, A heat source unit including a flow path having a predetermined length through which the mixed fuel passes, a catalyst layer formed on an inner surface of the flow path, and supplying a heat source for vaporizing the mixed fuel; And A channel having a predetermined length through which the mixed fuel passes, a catalyst layer is formed on an inner surface of the channel, and a reforming reaction unit generating hydrogen gas from the mixed fuel through a chemical catalytic reaction by the heat source, The heat source unit is a reformer for a fuel cell comprising a CO ₂ permeable membrane. The reformer of claim 1, wherein the CO ₂ permeable membrane is installed on one surface of an outer surface of a heat source portion. The reformer of claim 1, wherein the CO ₂ permeable membrane is formed by casting a polymer solution on a solid support and then removing a solvent. The reformer of claim 1, wherein the CO ₂ permeable membrane is a porous membrane or a nonporous membrane. The reformer for a fuel cell of claim 1, wherein the heat source unit is further provided with a heating member installed in contact with the flow path to heat the flow path. The reformer of claim 1, wherein the reformer further includes at least one carbon monoxide reduction unit connected to the flow path to remove carbon monoxide from the reformed gas generated by the reforming reaction unit. A stack for generating electricity by an electrochemical reaction of hydrogen and oxygen; A reformer for vaporizing a mixed fuel of liquid fuel and water containing hydrogen, and reforming the vaporized fluid to generate hydrogen gas; A fuel supply unit supplying a mixed fuel to the reformer; And An air supply for supplying external air to the stack, The reformer may include a heat path having a predetermined length through which the mixed fuel passes, a catalyst layer formed on an inner surface of the flow path, and supplying a heat source for vaporizing the mixed fuel; And A channel having a predetermined length through which the mixed fuel passes, a catalyst layer is formed on an inner surface of the channel, and a reforming reaction unit generating hydrogen gas from the mixed fuel through a chemical catalytic reaction by the heat source, The heat source unit comprises a CO ₂ permeable membrane. The fuel cell system as claimed in claim 7, wherein the CO ₂ permeable membrane is provided on one surface of an outer surface of a heat source portion. The fuel cell system as claimed in claim 7, wherein the CO ₂ permeable membrane is formed by casting a polymer solution on a solid support and then removing a solvent. 8. The fuel cell system according to claim 7, wherein the CO ₂ permeable membrane is a porous membrane or a nonporous membrane. 8. The fuel cell system according to claim 7, wherein the heat source portion further comprises a heating member which is installed in contact with the flow path and heats the flow path. The fuel cell system of claim 7, wherein the reformer further includes at least one carbon monoxide reduction unit connected to the flow path to remove carbon monoxide from the reformed gas generated by the reforming reaction unit. The fuel cell system of claim 7, wherein the fuel cell system is formed of a polymer electrolyte fuel cell (PEMFC) system.

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