KR101519945B1 - Oxidation reactor provided with guiding member - Google Patents

Abstract

The present invention relates to a selective oxidation reactor comprising a guiding member, and more specifically, to a selective oxidation reactor comprising a guiding member to guide reformed gas to a heat exchanger. To this end, the selective oxidation reactor by a catalyst of the present invention comprises: a case which supports the catalyst; a heat exchanger which is installed at the upper end of the catalyst inside the case and cools the reformed gas; a guiding member which guides the flow of the reformed gas to the heat exchanger; and an air spray nozzle which supplies the air from the guiding member in the direction opposite to the reformed gas flow direction.

Description

TECHNICAL FIELD [0001] The present invention relates to a selective oxidation reactor having an induction member,

The present invention relates to a selective oxidation reactor having an induction member, and more particularly to a selective oxidation reactor having an induction member for guiding a reformed gas to a heat exchanger.

In general, a fuel cell is an energy conversion device that directly converts chemical energy into electrical energy through a chemical reaction between fuel (hydrogen) and oxidant (oxygen) as a reverse reaction of the electrolysis reaction of water. The hydrogen gas supplied to the anode is separated into hydrogen ions and electrons after the catalyst is encountered. The hydrogen ions move to the cathode through the electrolyte and the electrons move to the anode through the external circuit. Move. The oxygen gas supplied to the anode is dissociated into oxygen atoms with the help of a catalyst, and then reacts with hydrogen ions moved from the electrolyte and electrons transferred to an external circuit to generate water.

Fuel cells can be roughly divided into alkali type fuel cells, phosphoric acid type fuel cells, polymer electrolyte fuel cells, direct methanol type fuel cells, molten carbonate type fuel cells and solid oxide type fuel cells depending on the type of electrolytes and the operation principle . Particularly in the case of polymer electrolyte fuel cells, a polymer membrane such as Nafion is used as an electrolyte, which works well when it contains sufficient water. Therefore, hydrogen and oxygen normally supplied to the fuel cell stack are supplied in a humidified state with a relative humidity of about 100%, and the polymer electrolyte membrane is supplied with moisture from the gas supplied as a reactant.

Most fuel cells, including polymer electrolyte fuel cells, use hydrogen as fuel. However, there is a limit to the use of hydrogen fuel cells in a state in which a supply system for hydrogen fuel is not established. Therefore, there is a need for a transitional system using fuel cells after reforming hydrocarbons such as natural gas, ethanol, gasoline, diesel, etc. to produce hydrogen. The fuel cell power system currently being developed is equipped with a fuel reformer for this reason. The fuel reformer can be divided into steam reforming, partial oxidation reforming and auto-thermal reforming according to the operation mode. The steam reforming is a method of obtaining hydrogen through the endothermic reaction between gasoline fuel and water vapor, and the hydrogen yield is good, but the continuous supply of heat is required from the outside. Partial oxidation reforming is a method of obtaining hydrogen by an exothermic reaction of gasoline fuel and oxygen, which has a relatively lower hydrogen yield than steam reforming, but does not require additional external heat supply. Autothermal reforming allows for more efficient reactor design by simultaneously using steam reforming and partial oxidation reforming. Therefore, in the case of a fuel cell power system operating in stand-alone mode, it is advantageous to apply a self-heating reforming method that does not require additional heat supply from outside and is quick in initial start-up.

After the catalytic reaction of the autothermal reformer, the hydrocarbon fuel is decomposed to produce a gaseous mass containing a large amount of hydrogen. Generally, the generated gas consists of hydrogen, carbon monoxide, carbon dioxide, nitrogen, and water vapor. Among these, carbon monoxide poisons the platinum catalyst of the polymer electrolyte fuel cell stack, making normal operation impossible. Therefore, the carbon monoxide generated after the autothermal reformer reaction must be removed to the ppm level through an additional reactor. In a typical fuel reformer, carbon monoxide is reduced to 1% level through a WGS (water gas shift) reactor and removed to ppm level by selective oxidation reaction (PROX). Thus, in general, most fuel reformers are equipped with WGS reactors, PROX reactors, as well as autothermal reforming reactors (in some cases, steam reforming, which can be replaced by partial oxidation reformers).

Oxygen is required for the selective oxidation reactor to work. Actual systems use air instead of oxygen. The selective oxidation reactor reacts carbon monoxide contained in the reformed gas with oxygen to become carbon dioxide (CO + 0.5O 2 ↔CO 2). However, if the operating condition of the selective oxidation reactor is not satisfied, oxygen reacts with hydrogen contained in a large amount of the reformed gas instead of carbon monoxide in the reformed gas to generate water, and hydrogen and carbon react to generate methane. These unintended reactions should be careful not to react as much as possible because they consume hydrogen rapidly and cause a series of exothermic reactions.

In order to remove carbon monoxide through the catalytic reaction of the WGS catalyst, the reforming gases must satisfy three conditions. First, the temperature of the reforming gas entering the selective oxidation reactor must be within the temperature range for selective oxidation catalysis to occur. Typical selective oxidation catalytic reaction temperature is 110 ~ 220 degrees. If the temperature of the reforming gas does not meet the selective oxidation catalytic reaction temperature, the reforming gas should be heated or cooled using an auxiliary device. Generally, in a fuel reformer, a selective oxidation reactor is installed after the WGS reactor. Usually, the temperature of the reforming gas at the rear end of the WGS reactor is 220 ° C. or more, and therefore, cooling through a heat exchanger is required.

The second factor required for selective oxidation is oxygen. The selective oxidation reaction produces carbon dioxide by the reaction of carbon monoxide and oxygen. Therefore, it is necessary to predict the amount of carbon monoxide contained in the reformed gas and to supply the stoichiometric oxygen at the tip of the selective oxidation reactor. Generally, in the fuel processor, the selective oxidation reaction is performed through the air supply.

The third element is mixed. The reformed gas and the externally supplied air should be as homogeneously mixed as possible and then fed to the catalyst bed. Given that the selective oxidation reaction is an exothermic reaction, heterogeneous mixing refers to localized heat generation in the catalyst bed. Therefore, additional equipment for mixing the reforming gas and air is also needed.

In the conventional selective oxidation, a device for satisfying the above three factors is considered separately. In some cases, a device considered to be capable of simultaneously performing two out of the three processes has been proposed, but it has a disadvantage that the process cost is high due to a large volume and difficult processing.

Korean Patent Registration 10-105026

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a selective oxidation reactor (PROX) and a heat exchanger which can reduce weight and volume, Reactor.

To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a selective oxidation reactor comprising a catalytic oxidation reactor comprising a casing for supporting the catalyst, A heat exchanger for cooling the gas, an induction member for guiding the flow of the reformed gas to the heat exchanger, and an air injection hole for supplying air in the direction opposite to the flow direction of the reformed gas from the guide member.

The air supply hole communicates with an air supply port formed in the guide member through the case, thereby receiving air.

In addition, the air ejection openings are spaced a predetermined distance from the rim of the upper surface of the guide member in the radial direction, and are arranged in a plurality of circular shapes.

In addition, a space for canceling the pulsation of the pump is formed in the guide member.

In addition, the guide member is formed in a cylindrical shape having the space portion.

And a guide connecting the inner circumferential surface of the case and the rim of the guide member so that the guide member can be disposed at the center of the reactor case.

In addition, the plurality of guides are disposed along the rim of the guide member.

And a heat exchanger disposed between the case and the guide member in the form of a pipe.

Further, the heat exchanger is formed to be wound on the outer peripheral surface of the guide member between the inner peripheral surface of the case and the outer peripheral surface of the guide member.

One end of the heat exchanger is provided with a refrigerant inlet on a lower outer circumferential surface of the upper case of the case and the other end has a refrigerant outlet on an upper outer circumferential surface of the upper case of the case.

As described above, according to the selective oxidation reactor having the induction member according to the present invention, the selective oxidation reactor (PROX) and the heat exchanger are integrated, thereby reducing the weight and volume.

In addition, homogeneous mixing of the air supplied to the selective oxidation reactor can be expected.

Further, since the reformed gas mixed with air is introduced into the heat exchanger, heat exchange efficiency is improved.

Also, the induction member facilitates the manufacture of the heat exchanger.

1 is a perspective view illustrating a selective oxidation reactor having an induction member according to an embodiment of the present invention.
2 is a cross-sectional view illustrating a selective oxidation reactor having an induction member according to an embodiment of the present invention.

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

FIG. 1 is a perspective view of a selective oxidation reactor having an induction member according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view illustrating a selective oxidation reactor having an induction member according to an embodiment of the present invention.

As shown in FIGS. 1 and 2, a selective oxidation reactor having an induction member according to an embodiment of the present invention includes a catalyst 10, a lower case 102 for supporting a catalyst, A heat exchanger 200 installed inside the upper case 101 for cooling the reformed gas, a heat exchanger 200 for introducing the reformed gas into the heat exchanger 200, And an air ejection opening 303 for supplying air into the case 100. The guide member 300 includes a guide member 300,

The selective oxidation reactor includes a catalyst 10 in which a selective oxidation reaction takes place, a casing 100 for sealing the reformed gas and supporting the catalyst 10 and other structures, a heat exchanging unit 10 for lowering the temperature of the reformed gas supplied to the catalyst 10, And a reforming gas guiding member 300 for guiding the flow of the reforming gas to the heat exchanger 200. The guide member 300 is formed with a guide 320 connecting the inner circumferential surface of the case 100 and the edge of the guide member 300 so as to be disposed at the center of the case 100. The guides 320 are disposed along the rim of the guide member 300 to firmly support the guide member 300. In addition, the upper and lower surfaces of the guide member 300 are closed except for the air injection port 303 and the air supply pipe 302a, and the guide member 300 has a cylindrical shape.

First, in the selective oxidation reactor, air is injected through the air injection port 303 for chemical reaction, so that the reforming gas and air (oxygen) are mixed first. The air generated by the blower or the pump is introduced into the induction member 300 through the air supply port 302 communicating with the air injection port 303. The air is supplied to the induction member 300 through the air supply port 302, Respectively. Here, the size of the air supply port 302 is relatively smaller than the outer diameters of the catalyst 10 and the case 100. Therefore, it is not easy for the air supplied to the air supply port 302 to be mixed with the reformed gas. Therefore, in this embodiment, the reformed gas guide member 300 is utilized for mixing the reformed gas and the air.

The reformed gas induction member 300 basically serves to change the direction so that the reformed gas can flow around the heat exchanger 200. If the reforming gas guide member 300 is not present in the selective oxidation reactor equipped with the piping type heat exchanger 200, most of the reforming gas flows due to the fluid resistance rather than flowing around the heat exchanger, Most of the fluid flows into the region where there is no fluid resistance, such as an empty space in the pipe inner diameter. This reduces the heat exchange capacity of the heat exchanger 200. Therefore, the reformed gas can be efficiently cooled through the heat exchanger 200 by introducing the reformed gas around the heat exchanger 200 through the reformed gas induction member 300. In this embodiment, the reformed gas guiding member 300 can simultaneously perform the air supply role, the guide for manufacturing the piping heat exchanger, and the pulsation reduction of the pump, as well as the role of guiding the reformed gas.

In addition, the reformed gas induction member 300 plays a role in moving the reformed gas to the heat exchanger 200. The reforming gas guide member 300 is preferably a structure having a smaller outer diameter than the case 100 and is located in the center of the case 100. The reforming gas can induce the fluid resistance to move around the heat exchanger rather than move to the empty space between the small pipes due to the presence of the guide member 300. [

The heat exchanger 200 may be formed to be wound on the outer circumferential surface of the guide member 300 between the inner circumferential surface of the case 100 and the outer circumferential surface of the guide member 300 to thereby perform heat exchange more effectively. One end of the heat exchanger 200 has a refrigerant inlet 210 on the lower outer circumferential surface of the upper case 101 of the case 100 and the other end of the heat exchanger 200 is located on the upper side of the upper case 101 of the case 100 The refrigerant outlet 220 is provided on the outer circumferential surface so that the refrigerant supplied through the refrigerant inlet 210 spirals around the induction member 300 and exchanges heat with the reformed gas and then discharged through the refrigerant outlet 220 .

At this time, the reforming gas induction member 300 may also serve as an air supply source. That is, air supplied from an external air pump passes through the case 100 and communicates with the air supply port 302 formed inside the guide member. The air supplied through the air supply port 302 And the air is supplied to the air injection port 303 via the air supply pipe 302a to be mixed with the reformed gas. In the guide member 200, As shown in FIG. At this time, the supplied air should flow into the catalyst in a state of being maximally homogeneously mixed with the reforming gas. By using the reforming gas induction member 300, it is possible to distribute the air more widely and to expect homogeneous mixing with the reformed gas. In particular, the air injection port 303 formed on the upper surface of the reformed gas induction member 300 is formed so as to face the direction of the reformed gas flow, thereby improving the mixing effect. In addition, the air injection ports 303 are spaced apart from the edge circle of the upper surface of the guide member 300 in the radial direction by a predetermined distance, and a plurality of the air injection ports 303 are circularly arranged.

In addition, the guide member 300 is formed in a cylindrical shape having a space portion 301 to perform a function of canceling the pulsation of the pump.

In addition, the guide member can serve as a guide for improving manufacturing precision and workability of a heat exchanger manufactured in the form of a pipe (corrugated pipe). If the piping type heat exchanger is manufactured without the guide member 300, it is difficult to wind the piping on the same circumference. If the induction member 300 is present, the piping of the heat exchanger can be wound around the induction member, so that it is possible to manufacture more accurately and quickly.

Finally, the space formed inside the guide member can reduce the pulsation phenomenon of the air pump. A general air pump has a pulsating phenomenon, and does not supply a uniform amount of air but supplies sine waves. At this time, the inner space portion 301 of the guide member serves as an accumulator for reducing the pulsation phenomenon of the air pump.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, And all changes to the scope that are deemed to be valid.

10: Catalyst
100: Case
101: upper case
102: Lower case
200: heat exchanger
210: Refrigerant inlet
220: Refrigerant outlet
300: guide member
301:
302: air supply port
302a: air supply pipe
303: Air nozzle
320: Guide

Claims (10)

In a selective oxidation reactor using a catalyst,
A case for supporting the catalyst;
A heat exchanger installed at an upper end of the catalyst inside the case and cooling the reformed gas;
An induction member which is formed in a cylindrical shape having a space portion to induce the flow of the reformed gas into the heat exchanger and to cancel the pulsation of the pump therein, the upper surface and the lower surface being closed; And
And an air injection port formed on an upper surface of the guide member to supply air in a direction opposite to the direction of flow of the reformed gas from the guide member and maintain a constant flow inside the guide member,
Wherein the air ejection ports are spaced from each other by a predetermined distance radially inwardly from an edge circle of the upper surface of the guide member and are arranged in a plurality of circumferential directions of the upper surface of the guide member,
The lower surface of the guide member is formed with an air supply pipe for supplying air into the guide member,
The air supply pipe is connected to an air supply port passing through the case,
And the air injection port communicates with the air supply port.
delete delete delete delete The method according to claim 1,
And a guide connecting the inner circumferential surface of the case and the rim of the guide member so that the guide member can be disposed at the center of the reactor case.
The method according to claim 6,
Wherein a plurality of guides are disposed along the rim of the guide member.
8. The method of claim 7,
And a heat exchanger in the form of a pipe between the case and the guide member.
9. The method of claim 8,
Wherein the heat exchanger is formed to be wound on an outer peripheral surface of the guide member between an inner peripheral surface of the case and an outer peripheral surface of the guide member.
10. The method of claim 9,
Wherein one end of the heat exchanger has a refrigerant inlet port on a lower outer circumferential surface of the upper case of the case and the other end has a refrigerant outlet port on an upper outer circumferential surface of the upper case of the case.

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