KR20120007660A - Carbon monoxide reducer - Google Patents

Abstract

The present invention relates to a carbon monoxide reducer, and more particularly, a mixed gas inlet pipe having a mixed gas inlet through which a mixed gas of reformed gas and air flows into a lower side thereof; A catalyst layer provided on the flow path in which the mixed gas introduced from the mixed gas inlet flows from the upper side to the lower side, and provided outside the mixed gas inlet pipe; And a first heat exchange flow path provided in a space between the mixed gas inlet pipe and the catalyst layer, the heat exchange medium flowing from the lower side to the upper side, and the heat exchange medium heat exchanged in the first heat exchange channel, and then flowing from the upper side to the lower side. It relates to a carbon monoxide reducer comprising a partition wall for separating the second heat exchange flow path for heat exchange with the mixed gas.
The carbon monoxide reducer of the present invention can perform the heating of the catalyst layer and the cooling of the heat generated in the catalyst layer without the electric heater and has a compact structure.

Description

Carbon monoxide reducer {Preferential oxidation reactor}

The present invention relates to a carbon monoxide reducer, and more particularly, to a carbon monoxide reducer having a compact structure that can perform heating of the catalyst layer and cooling of heat generated in the catalyst layer without an electric heater.

There is a growing interest in renewable energy as an alternative to the depletion of resources and environmental problems such as global warming due to the indiscriminate use of fossil energy.

A fuel cell is a type of power generation system that produces electricity by the electrochemical reaction of hydrogen and oxygen. It consists of a fuel cell stack that produces electricity and various peripheral systems for implementing the stack's functions.

Depending on the type of electrolyte, the fuel cell is a molten carbonate type (MCFC: Molten Carbonate Fuel Cell), a solid oxide type (SOFC: Solid Oxide Fuel Cell), a solid polymer type (PEFC: Polymer Electrolyte Fule Cell), or a direct methanol type (DMFC: Direct). Methanol Fuel Cell).

For example, a solid polymer fuel cell (PEFC) is being developed as a power source for home, automobile, and mobile, and commercialization and commercialization are rapidly progressing in recent years.

On the other hand, in the fuel cell, water is generated by the reaction of hydrogen and oxygen, and electricity is obtained in this process, and a device for producing hydrogen supplied to the fuel cell is called a reformer.

The steam reformer is a device that produces hydrogen by chemical reaction with hydrocarbon and additionally supplied water, and is one of various hydrogen producing devices.

The steam reformer can be divided into a reforming step of producing hydrogen through a chemical reaction between hydrocarbon and water, a shift reaction step of converting carbon monoxide generated from the reforming step into carbon dioxide, and a carbon monoxide removal step to match the carbon monoxide concentration required in the fuel cell stack. have.

This reaction occurs continuously in the catalyst bed packed in the reformer. In the case of PROX reactor where carbon monoxide removal occurs, air is injected for the reaction and designed independently of the reforming reactor.

The reaction in the PROX reactor consists of a carbon monoxide removal reaction, a water formation reaction, and a side reaction of the methanation reaction. The side reaction consumes H2, which is the fuel of the fuel cell formed in the reforming reaction, thereby reducing the efficiency of the fuel cell and in the fuel cell. It causes fuel starvation and shortens the life of the fuel cell stack.

Therefore, since these side reactions are exothermic, there is a need for an electric heater for suppressing side reactions and a cooling source that absorbs the heat generated by the side reactions and maintains an appropriate temperature.

Electric heaters are usually inserted into the catalyst bed, which may be in contact with water inside the reactor, causing a short circuit and causing thermal damage to the catalyst because the catalyst is directly heated by the heater.

The present invention has been made to solve the problems of the prior art as described above is to provide a carbon monoxide reducer having a compact structure that can perform the heating of the catalyst layer and the cooling of the heat generated in the catalyst layer without an electric heater.

The object of the present invention is a mixed gas inlet pipe provided in the lower side is a mixed gas inlet through which the mixed gas of the reformed gas and air; A catalyst layer provided on the flow path in which the mixed gas introduced from the mixed gas inlet flows from the upper side to the lower side, and provided outside the mixed gas inlet pipe; And a first heat exchange flow path provided in a space between the mixed gas inlet pipe and the catalyst layer, the heat exchange medium flowing from the lower side to the upper side, and the heat exchange medium heat exchanged in the first heat exchange channel, and then flowing from the upper side to the lower side. And a carbon monoxide reducer including a partition wall that separates the second heat exchange path that exchanges heat with the mixed gas.

In one embodiment, a diffusion plate for diffusion of the mixed gas may be provided on the upper side of the mixed gas inlet pipe.

In one embodiment, a mixed gas deceleration port for reducing the speed of the mixed gas may be provided inside the mixed gas inlet pipe.

In one embodiment, the mixed gas deceleration port may be a metal mesh.

In one embodiment, a heat exchange medium deceleration port may be provided on the first heat exchange passage or the second heat exchange passage.

In one embodiment, the heat exchange medium deceleration port may be a metal mesh.

The partition wall may include a first outer wall contacting the first heat exchange path and a second outer wall contacting the second heat exchange path, and the space between the first outer wall and the second outer wall may be in a vacuum state. Can be.

In the present invention, since the heat exchange medium (cooling water) is used as a source for cooling the catalyst layer and heating (heating) of the mixed gas, the electric heater used in the conventional carbon monoxide reducer can be omitted, and the possibility of electric leakage due to the electric heater and the local There is an effect that can eliminate the destruction of the phosphorus catalyst.

In addition, since four tubes having different diameters and the internal structure are simple, the manufacturing process is simplified and suitable for mass production, and the production cost of the carbon monoxide reducer can be greatly reduced.

1 and 2 are cross-sectional views of the carbon monoxide reducer according to an embodiment of the present invention.

The terms or words used in this specification and claims are not to be construed as being limited to their ordinary or dictionary meanings, and the inventors may appropriately define the concept of terms in order to best describe their invention. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that the present invention.

Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a cross-sectional view of a carbon monoxide reducer (PrOx reactor) according to an embodiment of the present invention.

As shown in FIG. 1, the carbon monoxide reducer according to the exemplary embodiment of the present invention may include a mixed gas inlet pipe 100, a catalyst layer 200, and a partition wall 350 forming a heat exchange path 300. have.

The mixed gas inlet 102 is provided at the lower side of the mixed gas inlet tube 100, and the mixed gas inlet 102 through which the mixed gas of the reformed gas and air is introduced, and the mixed gas introduced through the mixed gas inlet 102 is mixed gas inlet tube 100. Go through the inside of and move upwards.

The mixed gas moved upwards is controlled while being hit by the diffusion plate 400 provided on the upper side of the carbon monoxide reducer according to the exemplary embodiment of the present invention, and more uniformly mixed.

The mixed gas inlet pipe 100 may be a cylindrical pipe having a circular cross section, but the cross-sectional shape thereof is not limited and may be a polygonal shape, an elliptical shape, or the like depending on the overall shape of the carbon monoxide reducer.

The mixed gas inlet pipe 100 and the diffusion plate 400 may be made of a metal material such as stainless steel, but the material is not limited thereto.

In addition, although the diffusion plate 400 is illustrated as a flat plate in FIG. 1, it may be in the form of a cone, or a plurality of irregularities may be provided in the flat plate.

The mixed gas uniformly mixed by the diffusion plate 400 passes through the upper perforated plate 250 to support the catalyst (layer), enters the catalyst layer 200, and then passes through the lower perforated plate 260 to discharge the mixed gas outlet 150. Is discharged through).

The perforated plates 250 and 260 may be perforated plates in which a plurality of holes are formed in the metal plate, but the material and the size or number of the holes are not limited.

The catalyst layer 200 is provided on the flow path in which the mixed gas introduced from the mixed gas inlet 102 flows from the lower side to the upper side along the mixed gas inlet pipe 100 and then flows from the upper side to the lower side again.

The catalyst layer 200 is provided on the outside of the mixed gas inlet pipe 100, the heat exchange passage 300 described later is formed in the inner space of the catalyst layer 200 and the mixed gas inlet pipe 100, Inside and outside the catalyst layer, there is a catalyst layer inner tube 204 and a catalyst layer exterior 202 that protect or surround the catalyst layer 200.

As the catalyst, a platinum catalyst, a ruthenium catalyst, an oxide catalyst such as CuO / CeO ₂ may be used, but the present invention is not limited thereto.

In addition, the catalyst layer 200 may be in the form of a catalyst coated on a porous member such as a sponge, the mixed gas flows through a number of holes of the porous member and increases the contact area with the catalyst coated on the porous member to increase the reaction efficiency It can be configured to improve.

As the mixed gas passes through the catalyst bed, the following exothermic reaction occurs.

Scheme 1

However, in addition to the carbon monoxide removal reaction, the following side reactions (water formation reaction, methanation reaction) occur, and all of the following side reactions are exothermic.

Scheme 2

Scheme 3

The side reactions of Schemes 2 and 3 consume H ₂ , which is used as fuel in the fuel cell, causing fuel starvation in the fuel cell, thereby shortening the life of the fuel cell.

Therefore, in order not to cause the side reaction, a cooling source capable of removing heat due to the exothermic reaction is required, and the cooling function is performed in the heat exchange flow path described below, especially the first heat exchange flow path.

The heat exchange passage 300 is provided in a space between the mixed gas inlet pipe 100 and the catalyst layer 200, and the first heat exchange passage 300a and the first heat exchange medium in which the heat exchange medium flows from the lower side to the upper side exchange heat with the catalyst layer 200. After the heat exchange in the heat exchange passage flows from the upper side to the lower side may be made of a second heat exchange passage (300b) for heat exchange with the mixed gas.

The heat exchange medium may be a cooling water or the like, and in addition, any material having good heat transfer efficiency may be used as well as additives may be included in the cooling water.

The cooling water (heat exchange medium) may be branched from the cooling line for cooling the stack on the fuel cell system and the temperature at this time absorbs the heat from the PROX reaction at about 50 to 70 ° C.

The heat exchange medium introduced into the heat exchange medium inlet 302 moves upward from the bottom of the first heat exchange path 300a to absorb heat generated from the catalyst layer 200, and the temperature of the heat exchange medium gradually increases as it moves upward. .

The inner and outer tubes 202 and 204 of the catalyst layer 200 may be formed of a metal pipe having a high heat transfer coefficient in order to increase the heat transfer efficiency between the heat exchange medium and the catalyst layer 200.

The heat exchange medium moved upwardly moves downward from the upper side of the second heat exchange flow path 300b and transfers the heat absorbed by the catalyst layer 200 to the mixed gas of the reformed gas and the air flowing inside the mixed gas inlet pipe 100. You will.

The partition wall 350 exists between the first heat exchange path 300a and the second heat exchange path 300b, and the partition 350 separates the first heat exchange path 300a and the second heat exchange path 300b. .

The partition wall 350 serves to prevent the heat between the heat exchange medium moving through the first heat exchange path 300a and the heat exchange medium moving through the second heat exchange path 300b to prevent movement. It may be made of a material having a small coefficient, and may be manufactured by coating or coating an insulator such as polyurethane on a thin metal plate.

In addition, the partition wall 350 may be configured of a first outer wall contacting the first heat exchange path 300a and a second outer wall contacting the second heat exchange path 300b, and the space between the first outer wall and the second outer wall is in a vacuum state. The heat exchange between the first heat exchange passage 300a and the second heat exchange passage 300b may be prevented from being formed.

Carbon monoxide reducer according to an embodiment of the present invention may be composed of four cylindrical pipes having different diameters.

That is, the innermost mixed gas inlet pipe 100, the bulkhead wall 350 having a larger diameter than the mixed gas inlet pipe 100, the catalyst layer inner tube 202 having a larger diameter than the partition wall 350, and the exterior of the catalyst layer ( 204).

2 is a cross-sectional view of a carbon monoxide reducer according to an embodiment of the present invention.

Hereinafter, a description will be given with reference to FIG. 2, but description of parts overlapping with the above description will be omitted.

As shown in FIG. 2, the carbon monoxide reducer according to the exemplary embodiment of the present invention reduces the speed of the mixed gas on the mixed gas flow path inside the mixed gas inlet pipe 100 to increase the heat exchange efficiency. The tool 110 may be provided.

The mixed gas deceleration port 110 may be a metal mesh, or may be a spiral flow path formed inside the mixed gas inlet pipe 100, and the material and shape thereof are not limited thereto.

On the other hand, it may further include a heat exchange medium reduction port 310 for the deceleration of the heat exchange medium. In FIG. 2, the heat exchanging medium deceleration port is illustrated only on the first heat exchange path 300a, but the heat exchange medium deceleration port may also be included in the second heat exchange path 300b, as well as the first heat exchange medium 300a or the second heat exchange medium 300a. It may exist only in either one of the heat exchange flow paths 300b.

The heat exchange medium reduction port 310 may be a metal mesh, or may be a structure formed inside the heat exchange path 300 to allow the heat exchange medium to form a spiral flow path, and the material and shape thereof are not limited thereto.

Meanwhile, in the mixed gas deceleration port 110 and / or the heat exchange medium deceleration port 310, the deceleration means not only a case where the speed of the fluid is lowered, but also the speed is the same, but the length of the flow path is increased so that the movement distance in the up / down direction per unit time is increased. Decreases (speed) means including the case of playing a role.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, Various changes and modifications will be possible.

100: mixed gas inlet pipe 110: mixed gas deceleration port
200: catalyst layer 202: catalyst layer outer wall
204: inner wall of the catalyst layer 250, 260: perforated plate
300: heat exchange path 310: heat exchange medium reducer
350: bulkhead

Claims (7)

A mixed gas inlet pipe having a mixed gas inlet through which a mixed gas of reformed gas and air flows into a lower side thereof;
A catalyst layer provided on the flow path in which the mixed gas introduced from the mixed gas inlet flows from the upper side to the lower side, and provided outside the mixed gas inlet pipe; And
It is provided in the space between the mixed gas inlet pipe and the catalyst layer, the heat exchange medium flows from the lower side to the upper side and the first heat exchange passage for heat exchange with the catalyst layer and the heat exchange medium exchanges in the first heat exchange passage and flows from the upper side to the lower side Bulkhead separating the second heat exchange flow path for heat exchange with the mixed gas
Carbon monoxide reducer comprising a.
The method of claim 1,
Carbon monoxide reducer provided with a diffusion plate for the diffusion of the mixed gas on the upper side of the mixed gas inlet pipe.
The method of claim 1,
The carbon monoxide reducer is provided in the mixed gas inlet pipe is provided with a mixed gas deceleration port for reducing the speed of the mixed gas.
The method of claim 3,
The mixed gas deceleration port is a carbon monoxide reducer of the metal material.
The method of claim 1,
And a heat exchange medium reduction port is provided on the first heat exchange passage or the second heat exchange passage.
The method of claim 5,
The heat exchange medium deceleration port is a carbon monoxide reducer made of a metal mesh.
The method of claim 1,
The partition wall includes a first outer wall in contact with the first heat exchange path, a second outer wall in contact with the second heat exchange path, the space between the first outer wall and the second outer wall is a carbon monoxide reducer.

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