KR20230171796A - Ammonia decomposition apparatus for hydrogen producing and ammonia decomposition method of the same - Google Patents

Abstract

An ammonia decomposition device for producing hydrogen according to one aspect of the present invention includes an ammonia decomposition pipe through which ammonia moves, an ammonia decomposition catalyst installed inside the ammonia decomposition pipe to decompose ammonia, oxidizing exhaust gas to generate heat, and exhaust gas. It may include an exhaust gas combustion catalyst that removes residual ammonia within and transfers heat to the decomposition pipe, and a housing that accommodates the exhaust gas combustion catalyst and the decomposition pipe.

Description

Ammonia decomposition device for hydrogen production and ammonia decomposition method using the same {AMMONIA DECOMPOSITION APPARATUS FOR HYDROGEN PRODUCING AND AMMONIA DECOMPOSITION METHOD OF THE SAME}

The present invention relates to an apparatus and method for decomposing ammonia to produce hydrogen.

Carbon dioxide generated from the use of fossil fuels, the main energy source, is causing abnormal climate changes, including global warming. In addition, the fossil fuel has problems such as the fact that it is an existing resource whose reserves are limited to certain geographical areas, so continuous use is not possible, price volatility is large depending on social and economic issues, and the supply chain becomes unstable. . Accordingly, research and development is underway to break away from the energy system dependent on fossil fuels and utilize hydrogen as a new energy source.

Hydrogen is a hydrogen molecule (H2) in which two hydrogen atoms are covalently bonded. Unlike fossil fuels that emit greenhouse gases and fine dust, hydrogen does not emit any carbon dioxide and is an ideal clean energy source as water is emitted as a by-product. As a way to utilize the above hydrogen as a fuel source for automobiles, commercialization is already in progress, and research on hydrogen production technology is in progress to ensure a stable supply of hydrogen.

One way to efficiently store and transport hydrogen is to use ammonia as a hydrogen source. Since the process of decomposing ammonia into hydrogen and nitrogen is an endothermic process, energy is required to obtain the product. Accordingly, a device that can efficiently decompose ammonia while minimizing energy consumption is needed.

Additionally, at the beginning of operation of the ammonia decomposition device, there is a problem in that a large amount of undecomposed ammonia is generated due to the low temperature of the catalyst. Ammonia is a toxic substance, so it is necessary to remove and discharge residual ammonia contained in the exhaust gases of fuel cells, engines, turbines, and combustors that use ammonia.

Based on the technical background described above, the present invention provides an ammonia decomposition device and ammonia decomposition method for efficiently decomposing ammonia and producing hydrogen with improved thermal efficiency.

An ammonia decomposition device for producing hydrogen according to one aspect of the present invention includes an ammonia decomposition pipe through which ammonia moves, an ammonia decomposition catalyst installed inside the ammonia decomposition pipe to decompose ammonia, oxidizing exhaust gas to generate heat, and exhaust gas. It may include an exhaust gas combustion catalyst that removes residual ammonia within and transfers heat to the decomposition pipe, and a housing that accommodates the exhaust gas combustion catalyst and the decomposition pipe.

The exhaust gas combustion catalyst according to one aspect of the present invention may be installed to surround the decomposition pipe.

The exhaust gas combustion catalyst according to one aspect of the present invention may be arranged in a ring shape.

The ammonia decomposition device according to one aspect of the present invention may further include a nitrogen oxide reduction catalyst installed inside the decomposition tube to adsorb ammonia and disposed downstream of the exhaust gas combustion catalyst to reduce nitrogen oxides.

The ammonia decomposition device according to one aspect of the present invention may further include an ammonia oxidation catalyst installed inside the decomposition tube and disposed upstream of the exhaust gas combustion catalyst to oxidize ammonia.

The ammonia decomposition device according to one aspect of the present invention sprays ammonia into the decomposition pipe, and may further include an intermediate supply pipe that sprays ammonia between the ammonia oxidation catalyst and the main catalyst.

The ammonia decomposition device according to one aspect of the present invention may further include a heating device that is inserted into the ammonia oxidation catalyst and heats the ammonia oxidation catalyst.

According to one aspect of the present invention, a plurality of partition walls are formed inside the housing, an exhaust gas combustion catalyst is filled between the partition walls, and a heat exchanger may be coupled to the housing.

The ammonia decomposition method for producing hydrogen according to one aspect of the present invention includes an ammonia decomposition step of oxidizing and decomposing ammonia using a main catalyst installed inside the decomposition tube to generate decomposition gas containing hydrogen, nitrogen, and undecomposed ammonia. , and an exhaust gas catalyst combustion step of removing residual ammonia in the exhaust gas by oxidizing the exhaust gas using an exhaust gas combustion catalyst, and transferring the heat generated at this time to the decomposition pipe to heat the decomposition pipe.

The exhaust gas catalytic combustion step according to one aspect of the present invention may heat the decomposition pipe using an exhaust gas combustion catalyst installed to surround the decomposition pipe.

The ammonia decomposition method according to one aspect of the present invention may further include a nitrogen oxide reduction step of adsorbing ammonia contained in the decomposition gas and reducing nitrogen oxides using a nitrogen oxide reduction catalyst disposed downstream of the main catalyst. You can.

In the nitrogen oxide reduction step according to one aspect of the present invention, if it is determined that ammonia is excessively adsorbed on the nitrogen oxide reduction catalyst, ammonia can be removed by adjusting the supply amount of air to increase the amount of nitrogen oxides generated.

The ammonia decomposition method according to one aspect of the present invention may further include an ammonia oxidation step of oxidizing ammonia using an oxidation catalyst disposed upstream of the main catalyst.

The ammonia oxidation step according to one aspect of the present invention can maintain the temperature of the main catalyst constant by controlling the flow rate of ammonia and air supplied to the oxidation catalyst while heating the decomposition tube using the exhaust gas combustion catalyst. there is.

The ammonia decomposition step according to one aspect of the present invention may supply ammonia through an intermediate supply pipe installed between the oxidation catalyst and the main catalyst and decompose the ammonia supplied through the decomposition pipe and the intermediate supply pipe.

In the ammonia decomposition step according to one aspect of the present invention, ammonia and air are supplied to the main catalyst, and the heat generated at this time is transferred to the exhaust gas combustion catalyst to heat the exhaust gas combustion catalyst.

The ammonia decomposition method according to one aspect of the present invention may further include a heat exchange step of heating the fluid using a heat exchanger that receives heat from the exhaust gas combustion catalyst.

The hydrogen production device according to one aspect of the present invention includes an exhaust gas combustion catalyst that generates heat by oxidizing the exhaust gas and transfers heat to the ammonia decomposition pipe, so that not only the ammonia decomposition efficiency is improved, but also the residual ammonia can be efficiently removed. there is.

Figure 1 is a configuration diagram showing an ammonia decomposition device according to a first embodiment of the present invention.
Figure 2 is a cross-sectional view of the ammonia decomposition device according to the first embodiment of the present invention cut in the longitudinal direction.
Figure 3 is a cross-sectional view taken along line III-III in Figure 2.
Figure 4 is a flowchart for explaining the ammonia decomposition method according to the first embodiment of the present invention.
Figure 5 is a configuration diagram showing an ammonia decomposition device according to a second embodiment of the present invention.
Figure 6 is a cross-sectional view cut in the longitudinal direction of the ammonia decomposition device according to the second embodiment of the present invention.
Figure 7 is a flowchart for explaining the ammonia decomposition method according to the second embodiment of the present invention.
Figure 8 is a configuration diagram showing an ammonia decomposition device according to a third embodiment of the present invention.
Figure 9 is a cross-sectional view cut in the longitudinal direction of the ammonia decomposition device according to the third embodiment of the present invention.
Figure 10 is a cross-sectional view taken along line X-X in Figure 9.
Figure 11 is a flowchart for explaining the ammonia decomposition method according to the third embodiment of the present invention.

Since the present invention can be modified in various ways and can have various embodiments, specific embodiments will be exemplified and explained in detail in the detailed description. However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all transformations, equivalents, and substitutes included in the spirit and technical scope of the present invention.

The terms used in the present invention are only used to describe specific embodiments and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In the present invention, terms such as 'include' or 'have' are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. At this time, note that in the attached drawings, like components are indicated by the same symbols whenever possible. Additionally, detailed descriptions of well-known functions and configurations that may obscure the gist of the present invention will be omitted. For the same reason, some components are exaggerated, omitted, or schematically shown in the accompanying drawings.

Hereinafter, an ammonia decomposition device according to the first embodiment of the present invention will be described.

FIG. 1 is a configuration diagram showing an ammonia decomposition device according to a first embodiment of the present invention, FIG. 2 is a cross-sectional view cut longitudinally of an ammonia decomposition device according to a first embodiment of the present invention, and FIG. 3 is FIG. This is a cross-sectional view taken along line Ⅲ-Ⅲ in 2.

1 to 3, the ammonia decomposition device 101 according to the first embodiment includes a housing 110, a decomposition pipe 120, a main catalyst 121, a nitrogen oxide reduction catalyst 123, It may include an exhaust gas combustion catalyst (116). The ammonia decomposition device 101 oxidizes and decomposes ammonia using a catalyst to generate decomposition gas containing hydrogen, nitrogen, and undecomposed ammonia.

The decomposed gas is supplied to and used in the oxidation device 180, which may be comprised of a fuel cell, gas turbine, combustor, or internal combustion engine. The oxidation device 180 can oxidize decomposed gas to generate heat or generate power and electricity. The oxidation device 180 is connected to the decomposition pipe 120 and receives decomposition gas from the decomposition pipe 120. Additionally, an additional supply pipe 181 that supplies additional ammonia and air may be installed in the oxidation device 180.

The housing 110 may be cylindrical or hexahedral, and is shaped like a box with an internal space. An exhaust gas inlet 112 through which the exhaust gas discharged from the oxidation device 180 flows may be formed on one side of the housing 110, and an exhaust gas outlet 114 through which the exhaust gas is discharged may be formed on the other side.

The decomposition gas containing hydrogen generated in the ammonia decomposition device 101 is supplied to the oxidation device 180 and used therein, and is then converted to exhaust gas and re-introduced to the ammonia decomposition device 101. Accordingly, the heat contained in the exhaust gas can be used.

Meanwhile, the decomposition pipe 120 is installed to penetrate the housing 110 in the longitudinal direction and provides a passage through which ammonia moves. Ammonia can be supplied in gaseous form or sprayed in liquid form. Ammonia receives heat as it passes through the decomposition tube 120 and is converted into decomposition gas containing hydrogen.

A main catalyst 121 that oxidizes and decomposes ammonia is installed in the decomposition pipe 120. The main catalyst 121 may be a partial oxidation catalyst that partially oxidizes ammonia or a decomposition catalyst containing ruthenium. However, the present invention is not limited to this, and the main catalyst 121 may be made of various types of catalysts including noble metals and ruthenium.

The nitrogen oxide reduction catalyst 123 may be installed in the decomposition tube, but may be placed downstream of the main catalyst 121. The nitrogen oxide reduction catalyst 123 reduces nitrogen oxides into nitrogen molecules and water using ammonia contained in the decomposition gas generated while passing through the main catalyst 121. The nitrogen oxide reduction catalyst 123 may be made of a selective reduction catalyst (SCR).

The decomposed gas from which nitrogen oxides are removed in the nitrogen oxide reduction catalyst 123 can be supplied to the oxidation device 180 and used as fuel. In this way, according to this embodiment, the nitrogen oxide reduction catalyst 123 is installed inside the decomposition pipe 120 to efficiently remove nitrogen oxide contained in the decomposition gas.

In addition, the nitrogen oxide reduction catalyst 123 can adsorb and remove remaining ammonia, and the ammonia adsorbed on the nitrogen oxide reduction catalyst 123 can be removed by reacting with nitrogen oxide. That is, if it is determined that ammonia is excessively adsorbed on the nitrogen oxide reduction catalyst 123, the amount of nitrogen oxide generated can be increased by adjusting the supply amount of air to remove ammonia.

Meanwhile, an exhaust gas combustion catalyst 116 is installed inside the housing 110 to generate heat by oxidizing the exhaust gas. The exhaust gas combustion catalyst 116 oxidizes the exhaust gas to remove residual ammonia in the exhaust gas, and transfers the heat generated at this time to the decomposition pipe 120 to heat the decomposition pipe 120. In addition, the heat generated in the decomposition pipe 120 is transferred to the exhaust gas combustion catalyst 116, so that the combustion efficiency of the exhaust gas combustion catalyst 116 can be improved.

The exhaust gas combustion catalyst 116 is disposed on the outside of the decomposition pipe 120 and may be installed to surround the decomposition pipe 120. Additionally, the exhaust gas combustion catalyst 116 according to this embodiment may be arranged in a ring shape. The exhaust gas combustion catalyst 116 may be made of a combustion catalyst containing precious metals such as platinum and palladium. When the exhaust gas discharged from the oxidation device 180 flows into the housing 110, the exhaust gas is burned by the exhaust gas combustion catalyst 116 and a lot of heat is generated. At this time, residual ammonia contained in the exhaust gas can be removed.

As described above, according to this embodiment, the exhaust gas combustion catalyst 116 is installed to surround the decomposition pipe 120 and efficiently heats the decomposition pipe 120, so ammonia decomposition efficiency and thermal efficiency can be improved. In addition, the nitrogen oxide reduction catalyst 123 is installed inside the decomposition pipe 120, so that the emissions of nitrogen oxide and ammonia can be reduced.

Hereinafter, a method for decomposing ammonia according to the first embodiment of the present invention will be described.

Figure 4 is a flowchart for explaining the ammonia decomposition method according to the first embodiment of the present invention.

1 to 4, the ammonia decomposition method according to this embodiment may include an ammonia decomposition step (S101), a nitrogen oxide reduction step (S102), and an exhaust gas catalytic combustion step (S103).

The ammonia decomposition step (S101) oxidizes and decomposes ammonia using the main catalyst 121 to generate decomposition gas containing hydrogen, nitrogen, and undecomposed ammonia. The ammonia decomposition step (S101) oxidizes ammonia by supplying ammonia and air into the decomposition pipe 120, and transfers heat to the exhaust gas combustion catalyst 116 surrounding the decomposition pipe 120 to oxidize the exhaust gas combustion catalyst 116. It can be heated.

The nitrogen oxide reduction step (S102) reduces nitrogen oxides contained in the decomposition gas into nitrogen molecules and water using the nitrogen oxide reduction catalyst 123 disposed downstream of the main catalyst 121. Additionally, the nitrogen oxide reduction step (S102) adsorbs remaining ammonia, and the ammonia adsorbed on the nitrogen oxide reduction catalyst 123 can be removed by reacting with nitrogen oxide.

In the nitrogen oxide reduction step (S102), if it is determined that ammonia is excessively adsorbed on the nitrogen oxide reduction catalyst 123, ammonia can be removed by adjusting the supply amount of air to increase the amount of nitrogen oxides generated.

The exhaust gas catalytic combustion step (S103) oxidizes the exhaust gas using the exhaust gas combustion catalyst 116 surrounding the decomposition pipe 120 to remove residual ammonia in the exhaust gas, and transfers the heat generated at this time to the decomposition pipe 120. This heats the decomposition pipe 120.

Hereinafter, an ammonia decomposition device according to a second embodiment of the present invention will be described.

Figure 5 is a configuration diagram showing an ammonia decomposition device according to a second embodiment of the present invention, and Figure 6 is a cross-sectional view of the ammonia decomposition device according to a second embodiment of the present invention cut in the longitudinal direction.

5 and 6, the ammonia decomposition device 102 according to the present embodiment is the ammonia decomposition device according to the first embodiment described above, except for the ammonia oxidation catalyst 125 and the intermediate supply pipe 128. Since it has the same structure as , duplicate description of the same structure will be omitted.

The ammonia oxidation catalyst 125 is installed inside the decomposition pipe 120 to oxidize ammonia flowing into the decomposition pipe 120. The ammonia oxidation catalyst 125 can partially oxidize ammonia by receiving air with an equivalence ratio of more than 1, and can also completely oxidize ammonia by receiving air with an equivalence ratio of 1 or less. The ammonia oxidation catalyst 125 may be made of a catalyst impregnated with a noble metal (platinum, palladium, rhodium, etc.).

A heating device 127 for heating the ammonia oxidation catalyst 125 may be installed in the ammonia oxidation catalyst 125. The heating device 127 may be made of a heating rod and may be inserted into the ammonia oxidation catalyst 125 to increase the temperature of the ammonia oxidation catalyst 125.

The ammonia oxidation catalyst 125 provides heat to the main catalyst 121 when the ammonia decomposition device 102 is started, thereby helping the main catalyst 121 to efficiently decompose ammonia. Additionally, when the temperature of the main catalyst 121 rises sufficiently, the reaction of the ammonia oxidation catalyst 125 may be reduced or stopped by controlling the supply of ammonia or oxygen flowing into the ammonia oxidation catalyst 125. Additionally, since ammonia does not contain carbon, there is an advantage that carbon adsorption of the catalyst does not occur during oxidation of ammonia.

Meanwhile, an intermediate supply pipe 128 is installed inside the decomposition pipe 120. The intermediate supply pipe 128 sprays ammonia into the decomposition pipe 120, and ammonia is distributed between the ammonia oxidation catalyst 125 and the main catalyst 121. Spray. The intermediate supply pipe 128 increases the flow rate of ammonia flowing into the main catalyst 121, thereby improving the decomposition efficiency of ammonia.

Hereinafter, a method for decomposing ammonia according to a second embodiment of the present invention will be described.

Figure 6 is a flowchart for explaining the ammonia decomposition method according to the second embodiment of the present invention.

5 and 6, the ammonia decomposition method according to this embodiment includes an ammonia oxidation step (S201), an ammonia decomposition step (S202), a nitrogen oxide reduction step (S203), and an exhaust gas catalytic combustion step (S204). It can be included.

Since the ammonia decomposition method according to this embodiment consists of the same process as the ammonia decomposition method according to the first embodiment described above except for the ammonia oxidation step (S201) and the ammonia decomposition step (S202), duplicate description of the same process is provided. Omit it.

The ammonia oxidation step (S201) oxidizes ammonia using the ammonia oxidation catalyst 125 disposed upstream of the main catalyst 121. The ammonia oxidation step (S201) can partially oxidize ammonia or completely oxidize ammonia. In the ammonia oxidation step (S201), ammonia can be oxidized by heating the ammonia oxidation catalyst 125 using the heating device 127, or by heating the ammonia oxidation catalyst 125 using the heating device 127. .

The ammonia oxidation step (S201) controls the flow rate of ammonia and air supplied to the oxidation catalyst (125) while heating the decomposition tube (120) using the exhaust gas combustion catalyst (116) to keep the temperature of the main catalyst (121) constant. can be maintained.

The ammonia decomposition step (S202) oxidizes and decomposes ammonia using the main catalyst 121 to generate decomposition gas containing hydrogen, nitrogen, and undecomposed ammonia. The ammonia decomposition step (S202) supplies ammonia through the intermediate supply pipe 128, decomposes ammonia using the gas discharged from the ammonia oxidation step (S201) and ammonia supplied through the intermediate supply pipe 128, and produces decomposed gas. can be created.

Hereinafter, an ammonia decomposition device according to a third embodiment of the present invention will be described.

Figure 8 is a configuration diagram showing an ammonia decomposition device according to a third embodiment of the present invention, Figure 9 is a cross-sectional view cut in the longitudinal direction of an ammonia decomposition device according to a third embodiment of the present invention, and Figure 10 is a This is a cross-sectional view taken along line Ⅹ-Ⅹ in 9.

8 to 10, the ammonia decomposition device 103 according to this embodiment is the same as the ammonia decomposition device according to the second embodiment described above, except for the housing 110 and the heat exchanger 150. Since it consists of a structure, duplicate descriptions of the same structure will be omitted.

A plurality of partition walls 117 are formed inside the housing 110, and an exhaust gas combustion catalyst 116 is filled between the partition walls 117. The decomposition pipe 120 may be installed between any one of the partition walls 117 described above. Figure 9 illustrates that two partition walls 117 are formed, but the present invention is not limited thereto. Meanwhile, the ends of the partition walls 117 in different directions are fixed to the inner wall of the housing 110, so that the exhaust gas moves in a zigzag path. In addition, exhaust gas combustion catalysts 116 are filled between the partition walls 117, so that the exhaust gas can be oxidized while moving between the partition walls 117.

Meanwhile, a heat exchanger 150 that receives heat from the housing 110 is coupled to the housing 110. The heat exchanger 150 receives heat from the exhaust combustion catalyst 116 and can supply it to the oxidation device 180 for heating air, etc.

Hereinafter, a method for decomposing ammonia according to a third embodiment of the present invention will be described.

Figure 11 is a flowchart for explaining the ammonia decomposition method according to the third embodiment of the present invention. 8 to 11, the ammonia decomposition method according to this embodiment includes an ammonia oxidation step (S301), an ammonia decomposition step (S302), a nitrogen oxide reduction step (S303), an exhaust gas catalytic combustion step (S304), A heat exchange step (S305) may be included.

Since the ammonia decomposition method according to this embodiment consists of the same process as the ammonia decomposition method according to the second embodiment described above except for the heat exchange step (S305), duplicate description of the same process will be omitted.

In the heat exchange step (S305), a fluid such as air is heated using the heat exchanger 150 that receives heat from the exhaust gas combustion catalyst 116. Here, the fluid may be composed of various fluids such as air, water, etc. supplied to the oxidation device 180.

A plurality of partition walls 117 are formed inside the housing 110, and an exhaust gas combustion catalyst 116 is filled between the partition walls 117, and the heat generated as the exhaust gas passes through the exhaust gas combustion catalyst 116 is transferred to a heat exchanger ( 150). Air heated in the heat exchange step (S305) may be supplied to the oxidation device.

Above, an embodiment of the present invention has been described, but those skilled in the art can add, change, delete or add components without departing from the spirit of the present invention as set forth in the patent claims. The present invention may be modified and changed in various ways, and this will also be included within the scope of rights of the present invention.

101, 102, 103: Ammonia decomposition device
110: housing 112: inlet
114: outlet 116: exhaust gas combustion catalyst
117: partition 120: decomposition pipe
121: Main catalyst 123: Nitrogen oxide reduction catalyst
125: Ammonia oxidation catalyst 128: Intermediate supply pipe
150: heat exchanger 180: oxidation device

Claims (17)

Ammonia decomposition tube through which ammonia moves;
An ammonia decomposition catalyst installed inside the ammonia decomposition pipe to decompose ammonia;
An exhaust gas combustion catalyst that oxidizes exhaust gas to generate heat, removes residual ammonia in the exhaust gas, and transfers heat to the decomposition tube; and
A housing accommodating the exhaust gas combustion catalyst and the decomposition pipe;
Ammonia decomposition device for hydrogen production comprising. According to claim 1,
The exhaust gas combustion catalyst is an ammonia decomposition device for hydrogen production installed to surround the decomposition pipe. According to clause 2,
An ammonia decomposition device for hydrogen production in which the exhaust gas combustion catalyst is arranged in a ring shape. According to claim 1,
An ammonia decomposition device for hydrogen production further comprising a nitrogen oxide reduction catalyst installed inside the decomposition tube and disposed downstream of the exhaust gas combustion catalyst to adsorb ammonia and reduce nitrogen oxides. According to claim 1,
An ammonia decomposition device for hydrogen production further comprising an ammonia oxidation catalyst installed inside the decomposition pipe and disposed on an upstream side of the exhaust gas combustion catalyst to oxidize ammonia. According to clause 5,
An ammonia decomposition device for producing hydrogen, which sprays ammonia into the decomposition pipe and further includes an intermediate supply pipe that sprays ammonia between the ammonia oxidation catalyst and the main catalyst. According to clause 6,
An ammonia decomposition device for hydrogen production further comprising a heating device inserted into the ammonia oxidation catalyst to heat the ammonia oxidation catalyst. According to clause 3,
An ammonia decomposition device for producing hydrogen in which a plurality of partition walls are formed inside the housing, an exhaust gas combustion catalyst is filled between the partition walls, and a heat exchanger is installed in the housing. An ammonia decomposition step of oxidizing and decomposing ammonia using the main catalyst installed inside the decomposition tube to generate decomposition gas containing hydrogen, nitrogen, and undecomposed ammonia; and
An exhaust gas catalyst combustion step of removing residual ammonia in the exhaust gas by oxidizing the exhaust gas using an exhaust gas combustion catalyst, and transferring the heat generated at this time to the decomposition pipe to heat the decomposition pipe;
Ammonia decomposition method for hydrogen production comprising. According to clause 9,
The exhaust gas catalytic combustion step is an ammonia decomposition method for producing hydrogen in which the decomposition pipe is heated using an exhaust gas combustion catalyst installed to surround the decomposition pipe. According to clause 9,
An ammonia decomposition method for producing hydrogen, further comprising a nitrogen oxide reduction step of adsorbing ammonia contained in the decomposition gas and reducing nitrogen oxides using a nitrogen oxide reduction catalyst disposed downstream of the main catalyst. According to claim 11,
In the nitrogen oxide reduction step, if it is determined that ammonia is excessively adsorbed on the nitrogen oxide reduction catalyst, the ammonia is removed by adjusting the supply amount of air to increase the amount of nitrogen oxides generated. According to clause 9,
Ammonia decomposition method for hydrogen production further comprising an ammonia oxidation step of oxidizing ammonia using an oxidation catalyst disposed upstream of the main catalyst. According to claim 13,
The ammonia oxidation step is an ammonia decomposition method for hydrogen production in which the temperature of the main catalyst is kept constant by controlling the flow rate of ammonia and air supplied to the oxidation catalyst while heating the decomposition pipe using the exhaust gas combustion catalyst. . According to claim 13,
The ammonia decomposition step is an ammonia decomposition method for hydrogen production in which ammonia is supplied through an intermediate supply pipe installed between the oxidation catalyst and the main catalyst and the ammonia supplied through the decomposition pipe and the intermediate supply pipe is decomposed. According to clause 9,
In the ammonia decomposition step, ammonia and air are supplied to the main catalyst, and the heat generated at this time is transferred to the exhaust gas combustion catalyst to heat the exhaust gas combustion catalyst. According to clause 9,
Ammonia decomposition method for hydrogen production further comprising a heat exchange step of heating the fluid using a heat exchanger that receives heat from the exhaust gas combustion catalyst.

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