A self-heating ammonia decomposition reactor

Abstract

The present invention provides a self-heating ammonia decomposition reactor, comprising an outer sleeve and an inner sleeve arranged inside the outer sleeve, wherein the inner sleeve is filled with a first catalyst, and the gap between the inner sleeve and the outer sleeve is filled with a second catalyst, wherein one of the first catalyst and the second catalyst is an ammonia decomposition catalyst, and the other is a catalytic combustion catalyst. The fuel gas generates heat under the action of the catalytic combustion catalyst and discharges the combustion exhaust gas; the ammonia gas undergoes an ammonia decomposition reaction under the action of the ammonia decomposition catalyst, and the heat required for the reaction process comes from the catalytic combustion of the fuel gas, that is, the device only needs to be filled with a catalytic combustion catalyst without the need to additionally set up a burner or other heat-generating device to perform the ammonia decomposition reaction, thereby effectively simplifying the device structure and reducing the equipment cost; at the same time, the later maintenance process of the equipment only needs to replace the catalytic combustion catalyst, reducing the difficulty and workload of equipment maintenance.

Description

Technical Field

[0001] The invention relates to the technical field of hydrogen production by decomposing ammonia, and in particular to a self-heating ammonia decomposition reactor. Background Art

[0002] Ammonia decomposition to produce hydrogen is a chemical reaction, which means that liquid ammonia is heated to 800-850°C and decomposed under the action of a nickel-based catalyst to obtain a hydrogen-nitrogen mixed gas containing 75% H2 and 25% N2. Raw material ammonia is easy to obtain, low in price, and consumes less raw materials. Therefore, the production of hydrogen by catalytic decomposition of ammonia is an efficient and reliable way to supply hydrogen to fuel cells.

[0003] Chinese patent CN110203882A discloses an ammonia decomposition device, which includes a shell, a reaction section and a heat exchange coil. The shell includes a heating zone and a heat exchange zone connected in sequence; the reaction section includes a first reaction section and a second reaction section connected in sequence, the first reaction section is arranged in the heating zone, and the second reaction section is arranged in the heat exchange zone; the heat exchange coil is spirally wound on the outer wall of the second reaction section and the first reaction section in sequence. Among them, a burner is also arranged in the heating zone and between the inner wall of the shell and the first reaction section. The fuel from the fuel tank enters the burner and burns. The heat generated is used to maintain the reaction temperature in the first reaction section. At the same time, the exhaust gas generated by the combustion enters the heat exchange zone to preheat the ammonia that has not entered the first reaction section for reaction; and maintain the reaction temperature entering the second reaction section. However, the setting of the burner increases the structural complexity of the ammonia decomposition device, and the open flame combustion is not only not conducive to temperature control, but also limits the application occasions of the device, and the equipment operation cost and the difficulty of later equipment maintenance also increase accordingly. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defects of the existing ammonia decomposition device, such as the complex structure and high equipment operation cost, thereby providing a self-heating ammonia decomposition reactor.

[0005] The present invention provides a self-heating ammonia decomposition reactor, comprising:

[0006] The outer sleeve comprises a first air inlet and a first air outlet respectively arranged at two ends thereof;

[0007] An inner sleeve is arranged inside the outer sleeve, the inner sleeve comprises a second air inlet and a second air outlet respectively arranged at two ends thereof and extending to the outside of the outer sleeve, the inner sleeve is filled with a first catalyst, and the gap between the inner sleeve and the outer sleeve is filled with a second catalyst, wherein one of the first catalyst and the second catalyst is an ammonia decomposition catalyst, and the other is a catalytic combustion catalyst;

[0008] The first air inlet or the second air inlet is suitable for communicating with fuel gas, and the fuel gas is suitable for exothermic reaction with a catalytic combustion catalyst.

[0009] Furthermore, the catalytic combustion catalyst is a hydrogen catalytic combustion catalyst or an ammonia catalytic combustion catalyst, and the hydrogen catalytic combustion catalyst is MgAl2O4, Mn-Co-Cu-Fe-Ni / γ-Al2O3 / cordierite, Pt / γ-Al2O3 / cordierite, Pt / Ce x Zr 1-x O2 / γ-Al2O3, the ammonia catalytic combustion catalyst is Fe2O3, V2O5, Cr2O3, MoO x , WO x At least one of;

[0010] The ammonia decomposition catalyst is a ruthenium-based ammonia decomposition catalyst, an iron-based ammonia decomposition catalyst or a nickel-based ammonia decomposition catalyst.

[0011] Furthermore, the autothermal ammonia decomposition reactor further comprises:

[0012] A heat-insulating material is arranged on the outer wall of the outer sleeve;

[0013] A thermocouple penetrates the outer wall of the outer sleeve.

[0014] Further, the first air inlet and the second air inlet are located on the same side of the autothermal ammonia decomposition reactor, and the first air outlet and the second air outlet are located on the same side of the autothermal ammonia decomposition reactor; or,

[0015] The first air inlet and the second air inlet are located at different sides of the autothermal ammonia decomposition reactor, and the first air outlet and the second air outlet are located at different sides of the autothermal ammonia decomposition reactor.

[0016] Furthermore, a first cylindrical baffle is radially arranged in the gap between the inner sleeve and the outer sleeve, the first cylindrical baffle and the inner sleeve have the same central axis, a plurality of holes are arranged on a side of the first cylindrical baffle close to the inner sleeve, a first flow channel is formed in the gap between the first cylindrical baffle and the outer sleeve, a second flow channel is formed in the gap between the first cylindrical baffle and the inner sleeve, one end of the first flow channel close to the first air inlet is open, one end of the first flow channel close to the first air outlet is closed, one end of the second flow channel close to the first air inlet is closed, and one end of the second flow channel close to the first air outlet is open.

[0017] Furthermore, an air intake pipe is arranged inside the inner sleeve, the air intake pipe is provided with a plurality of holes, one end of the air intake pipe is communicated with the second air inlet port, and the opposite end is sealed.

[0018] Furthermore, an air intake pipe is arranged inside the inner sleeve, the air intake pipe is provided with a plurality of holes, one end of the air intake pipe is communicated with the second air inlet port, and the opposite end is sealed.

[0019] Furthermore, a second cylindrical baffle is longitudinally arranged inside the inner sleeve, the second cylindrical baffle and the inner sleeve have the same central axis, the second cylindrical baffle is filled with a ruthenium-based ammonia decomposition catalyst, and the gap between the second cylindrical baffle and the inner sleeve is filled with a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst.

[0020] Further, a plurality of second cylindrical baffles are longitudinally arranged inside the inner sleeve, and the second cylindrical baffles and the inner sleeve have the same central axis to form a plurality of ammonia decomposition catalyst layers having the same central axis, wherein, in the direction from the inner sleeve to the central axis,

[0021] The applicable temperature of the ammonia decomposition catalyst decreases layer by layer; and / or

[0022] The particle size of the ammonia decomposition catalyst gradually decreases or increases, and the ratio of the particle size of the ammonia decomposition catalyst in the latter layer to that in the former layer is 0.25-4; and / or,

[0023] The pores of the ammonia decomposition catalyst gradually decrease or gradually increase, and the pores are 2nm-4000nm; and / or,

[0024] The porosity of the ammonia decomposition catalyst gradually decreases or increases, and the porosity is 0.1-0.7.

[0025] Furthermore, a first grid plate is provided in the inner sleeve, and the first grid plate abuts against the inner wall of the inner sleeve, wherein a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst is filled between the second air inlet and the first grid plate, and a ruthenium-based ammonia decomposition catalyst is filled between the second air outlet and the first grid plate.

[0026] Furthermore, a plurality of first grid plates are arranged in the inner sleeve, and the first grid plates are respectively in contact with the inner wall of the inner sleeve, so that a plurality of ammonia decomposition catalyst layers are formed inside the inner sleeve, wherein, along the direction of gas flow in the inner sleeve,

[0027] The applicable temperature of the ammonia decomposition catalyst decreases layer by layer; and / or,

[0028] The particle size of the ammonia decomposition catalyst gradually decreases or increases, and the ratio of the particle size of the ammonia decomposition catalyst in the latter layer to that in the former layer is 0.25-4; and / or,

[0029] The pores of the ammonia decomposition catalyst gradually decrease or gradually increase, and the pores are 2nm-4000nm; and / or,

[0030] The porosity of the ammonia decomposition catalyst gradually decreases or increases, and the porosity is 0.1-0.7.

[0031] Furthermore, a first grid plate is provided in the gap between the inner sleeve and the outer sleeve, and the first grid plate is respectively in contact with the outer wall of the inner sleeve and the inner wall of the outer sleeve, wherein a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst is filled between the first air inlet and the first grid plate, and a ruthenium-based ammonia decomposition catalyst is filled between the first air outlet and the first grid plate.

[0032] Further, a plurality of first grid plates are provided in the gap between the inner sleeve and the outer sleeve, and the first grid plates are respectively in contact with the outer wall of the inner sleeve and the inner wall of the outer sleeve, so that a plurality of ammonia decomposition catalyst layers are formed in the gap between the inner sleeve and the outer sleeve, wherein the gap between the inner sleeve and the outer sleeve is along the direction of gas flow.

[0033] The applicable temperature of the ammonia decomposition catalyst decreases layer by layer; and / or,

[0034] The particle size of the ammonia decomposition catalyst gradually decreases or increases, and the ratio of the particle size of the ammonia decomposition catalyst in the latter layer to that in the former layer is 0.25-4; and / or,

[0035] The pores of the ammonia decomposition catalyst gradually decrease or gradually increase, and the pores are 2nm-4000nm; and / or,

[0036] The porosity of the ammonia decomposition catalyst gradually decreases or increases, and the porosity is 0.1-0.7.

[0037] Furthermore, a second cylindrical baffle is longitudinally arranged in the gap between the inner sleeve and the outer sleeve, and the second cylindrical baffle and the inner sleeve have the same central axis, wherein the gap between the second cylindrical baffle and the inner sleeve is filled with a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst, and the gap between the second cylindrical baffle and the outer sleeve is filled with a ruthenium-based ammonia decomposition catalyst.

[0038] Further, a plurality of second cylindrical baffles are longitudinally arranged in the gap between the inner sleeve and the outer sleeve, and the second cylindrical baffles and the inner sleeve have the same central axis to form a plurality of ammonia decomposition catalyst layers having the same central axis, wherein, along the direction from the inner sleeve to the outer sleeve,

[0039] The applicable temperature of the ammonia decomposition catalyst decreases layer by layer; and / or

[0040] The particle size of the ammonia decomposition catalyst gradually decreases or increases, and the ratio of the particle size of the ammonia decomposition catalyst in the latter layer to that in the former layer is 0.25-4; and / or,

[0041] The pores of the ammonia decomposition catalyst gradually decrease or gradually increase, and the pores are 2nm-4000nm; and / or,

[0042] The porosity of the ammonia decomposition catalyst gradually decreases or increases, and the porosity is 0.1-0.7.

[0043] The technical solution of the present invention has the following advantages:

[0044] 1. The self-heating ammonia decomposition reactor provided by the present invention comprises an outer sleeve and an inner sleeve arranged inside the outer sleeve, the outer sleeve comprises a first air inlet and a first air outlet respectively arranged at two ends thereof, the inner sleeve comprises a second air inlet and a second air outlet respectively arranged at two ends thereof and extending to the outside of the outer sleeve, the interior of the inner sleeve is filled with a first catalyst, and the gap between the inner sleeve and the outer sleeve is filled with a second catalyst, wherein one of the first catalyst and the second catalyst is an ammonia decomposition catalyst, and the other is a catalytic combustion catalyst, the first air inlet or the second air inlet is suitable for connecting with fuel gas, and the fuel gas is suitable for exothermic reaction with the catalytic combustion catalyst.

[0045] After the fuel gas enters the autothermal ammonia decomposition reactor, it generates heat under the action of the catalytic combustion catalyst and discharges the combustion exhaust gas; after the ammonia gas enters the autothermal ammonia decomposition reactor, it undergoes an ammonia decomposition reaction under the action of the ammonia decomposition catalyst, and the heat required for the reaction process comes from the catalytic combustion of the fuel gas. Therefore, the device only needs to be filled with a catalytic combustion catalyst without the need to additionally set up a burner or other heat-generating device to carry out the ammonia decomposition reaction, thereby effectively simplifying the device structure and reducing the equipment cost; at the same time, the later maintenance process of the equipment only needs to replace the catalytic combustion catalyst, reducing the difficulty and workload of equipment maintenance.

[0046] 2. The self-heating ammonia decomposition reactor provided by the present invention provides heat for the ammonia decomposition reaction by filling a catalytic combustion catalyst. Compared with the conventional thermal combustion method, the catalytic combustion requires less auxiliary fuel and has low energy consumption, thereby reducing the energy consumption required for the ammonia decomposition reaction and reducing the material cost of the ammonia decomposition reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0048] Figure 1 This is a schematic diagram of the structure of the autothermal ammonia decomposition reactor provided in Example 1;

[0049] Figure 2 This is a schematic diagram of the structure of the autothermal ammonia decomposition reactor provided in Example 3;

[0050] Figure 3 This is a schematic diagram of the structure of the autothermal ammonia decomposition reactor provided in Example 5;

[0051] Figure 4 This is a schematic diagram of the structure of the autothermal ammonia decomposition reactor provided in Example 7;

[0052] Figure 5 This is a schematic structural diagram of the first autothermal ammonia decomposition reactor provided in Example 9;

[0053] Figure 6 This is a schematic structural diagram of the second autothermal ammonia decomposition reactor provided in Example 9;

[0054] Figure 7 This is a schematic structural diagram of the first autothermal ammonia decomposition reactor provided in Example 10;

[0055] Figure 8 This is a schematic structural diagram of the second autothermal ammonia decomposition reactor provided in Example 10;

[0056] Fig. 9 This is a schematic structural diagram of the third autothermal ammonia decomposition reactor provided in Example 10;

[0057] Fig.10 This is a schematic structural diagram of the fourth autothermal ammonia decomposition reactor provided in Example 10;

[0058] Fig.11 This is a schematic structural diagram of an autothermal ammonia decomposition reactor provided in Example 11;

[0059] Fig.12 This is a schematic structural diagram of the first autothermal ammonia decomposition reactor provided in Example 12;

[0060] Fig.13 This is a schematic structural diagram of the second autothermal ammonia decomposition reactor provided in Example 12;

[0061] Description of reference numerals:

[0062] 1-outer sleeve; 1-1-first air inlet; 1-2-first air outlet; 2-inner sleeve; 2-1-second air inlet; 2-2-second air outlet; 3-first cylindrical baffle; 4-inlet pipe; 5-second cylindrical baffle; 6-first grid; 7-insulating material; 8-thermocouple; 9-second grid; 10-inlet flowmeter; 11-outlet collector; 12-gas distributor; 13-sampling tube; 14-partition. DETAILED DESCRIPTION

[0063] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0064] In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0065] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0066] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0067] Example 1

[0068] like Figure 1 As shown, this embodiment provides an autothermal ammonia decomposition reactor, comprising:

[0069] The outer sleeve 1 comprises a first air inlet 1-1 and a first air outlet 1-2 respectively arranged at two ends thereof;

[0070] The inner sleeve 2 is arranged inside the outer sleeve 1. The inner sleeve 2 includes a second air inlet 2-1 and a second air outlet 2-2 which are arranged at both ends thereof and extend to the outside of the outer sleeve 1. The inner sleeve 2 is filled with an ammonia decomposition catalyst, and the gap between the inner sleeve 2 and the outer sleeve 1 is filled with a catalytic combustion catalyst.

[0071] The first air inlet 1-1 is suitable for communicating with fuel gas, and the fuel gas is suitable for exothermic reaction with a catalytic combustion catalyst.

[0072] The fuel gas enters the gap between the inner sleeve 2 and the outer sleeve 1 from the first air inlet 1-1, generates heat under the action of the catalytic combustion catalyst, and discharges the combustion exhaust gas from the first air outlet 1-2; the ammonia gas enters the inner sleeve 2 from the second air inlet 2-1, and performs an ammonia decomposition reaction under the action of the ammonia decomposition catalyst. The heat required for the reaction process comes from the catalytic combustion of the fuel gas, and the product is discharged through the second air outlet 2-2. Therefore, the device only needs to be filled with a catalytic combustion catalyst without the need to set up additional heat-generating devices such as burners to perform an ammonia decomposition reaction, thereby effectively simplifying the device structure and reducing the equipment cost; at the same time, the later maintenance process of the equipment only needs to replace the catalytic combustion catalyst, reducing the difficulty and workload of equipment maintenance.

[0073] Further, the catalytic combustion catalyst is a hydrogen catalytic combustion catalyst or an ammonia catalytic combustion catalyst, and the hydrogen catalytic combustion catalyst is MgAl2O4, Mn-Co-Cu-Fe-Ni / γ-Al2O3 / cordierite, Pt / γ-Al2O3 / cordierite, Pt / Ce x Zr 1- x At least one of O2 / γ-Al2O3, the ammonia catalytic combustion catalyst is Fe2O3, V2O5, Cr2O3, MoO x , WO x At least one of;

[0074] The ammonia decomposition catalyst is a ruthenium-based ammonia decomposition catalyst, an iron-based ammonia decomposition catalyst or a nickel-based ammonia decomposition catalyst.

[0075] As an optional embodiment, the first air inlet 1-1 and the second air inlet 2-1 are located on the same side of the autothermal ammonia decomposition reactor, and the first air outlet 1-2 and the second air outlet 2-2 are located on the same side of the autothermal ammonia decomposition reactor; or, the first air inlet 1-1 and the second air inlet 2-1 are located on different sides of the autothermal ammonia decomposition reactor, and the first air outlet 1-2 and the second air outlet 2-2 are located on different sides of the autothermal ammonia decomposition reactor.

[0076] Specifically, the autothermal ammonia decomposition reactor comprises:

[0077] The second grid plate 9 is close to the second gas outlet 2-2 and abuts against the inner wall of the inner sleeve 2. The space formed above the inner sleeve 2 and the second grid plate 9 is used to fill the ammonia decomposition catalyst. The inner sleeve 2 and the second grid plate 9 form a cavity below. The generated gas after ammonia decomposition enters the cavity through the second grid plate 9 and is then discharged through the second gas outlet 2-2. The gap between the inner sleeve 2 and the outer sleeve 1 is also provided with a second grid plate 9, which is arranged close to the first gas outlet 1-2 and abuts against the outer wall of the inner sleeve 2 and the inner wall of the outer sleeve 1 respectively. The space formed above the second grid plate 9 and the outer wall of the inner sleeve 2 and the inner wall of the outer sleeve 1 is used to fill the catalytic combustion catalyst.

[0078] The heat-insulating material 7 is arranged on the outer wall of the outer sleeve 1, thereby reducing the efficiency of heat generated by the catalytic combustion of the fuel gas to diffuse outward, thereby improving the utilization rate of the heat;

[0079] Thermocouple 8, which penetrates the outer wall of the outer sleeve 1, is used to monitor the temperature generated by the catalytic combustion catalyst, and then monitor the normal progress of the ammonia decomposition reaction;

[0080] An inlet flow meter 10 is provided at the first air inlet 1-1 and the second air inlet 2-1 to detect the gas flow entering the first air inlet 1-1 and the second air inlet 2-1 respectively;

[0081] The sampling tube 13 is arranged at the first gas outlet 1-2 and the second gas outlet 2-2 to detect the gas discharged from the first gas outlet 1-2 and the second gas outlet 2-2 respectively;

[0082] A gas distributor 12 is arranged at the first gas inlet 1-1 to make the gas entering the gap between the inner sleeve 2 and the outer sleeve 1 evenly distributed;

[0083] The outlet collector 11 is arranged at the first air outlet 1 - 2 and the second air outlet 2 - 2 to reduce local flow resistance.

[0084] Example 2

[0085] like Figure 1 As shown, this embodiment provides an autothermal ammonia decomposition reactor, which is different from the autothermal ammonia decomposition reactor provided in Example 1 in that:

[0086] The inner sleeve 2 is filled with a catalytic combustion catalyst, and the gap between the inner sleeve 2 and the outer sleeve 1 is filled with an ammonia decomposition catalyst;

[0087] The second air inlet 2-1 is suitable for communicating with fuel gas, and the fuel gas is suitable for exothermic reaction with the catalytic combustion catalyst.

[0088] The fuel gas enters the gap between the inner sleeve 2 and the outer sleeve 1 from the second air inlet 2-1, generates heat under the action of the catalytic combustion catalyst, and discharges the combustion exhaust gas from the second air outlet 2-2; the ammonia gas enters the inner sleeve 2 from the first air inlet 1-1, and performs an ammonia decomposition reaction under the action of the ammonia decomposition catalyst. The heat required for the reaction process comes from the catalytic combustion of the fuel gas, and the product is discharged through the first air outlet 1-2. Therefore, the device only needs to be filled with a catalytic combustion catalyst without the need to set up additional heat-generating devices such as burners to perform an ammonia decomposition reaction, thereby effectively simplifying the device structure and reducing the equipment cost; at the same time, the later maintenance process of the equipment only needs to replace the catalytic combustion catalyst, reducing the difficulty and workload of equipment maintenance.

[0089] Example 3

[0090] like Figure 2 As shown, this embodiment provides an autothermal ammonia decomposition reactor, which is different from the autothermal ammonia decomposition reactor provided in Example 1 in that:

[0091] The gap between the inner sleeve and the outer sleeve is radially provided with a first cylindrical baffle 3, the first cylindrical baffle 3 and the inner sleeve have the same central axis, a plurality of holes are provided on the side of the first cylindrical baffle 3 close to the inner sleeve, the gap between the first cylindrical baffle 3 and the outer sleeve forms a first flow channel, the gap between the first cylindrical baffle 3 and the inner sleeve forms a second flow channel, the first flow channel is open at one end close to the first air inlet, the first flow channel is closed at one end close to the first air outlet, the second flow channel is closed at one end close to the first air inlet, and the second flow channel is open at one end close to the first air outlet. The fuel gas enters the gap between the inner sleeve 2 and the outer sleeve 1 from the first air inlet 1-1 and then enters the first flow channel, and enters the second flow channel through the holes to react with the catalytic combustion catalyst. The arrangement of the first cylindrical baffle 3 and the holes increases the lateral flow of the fuel gas, thereby increasing the flow path of the fuel gas, increasing the catalytic combustion efficiency, and ultimately increasing the heat generation of the catalytic combustion catalyst, promoting the ammonia decomposition reaction.

[0092] Specifically, a partition is provided at one end of the gap between the first cylindrical baffle plate 3 and the outer sleeve near the first air outlet 1-2 to close the end, a partition is provided at one side of the gap between the first cylindrical baffle plate 3 and the inner sleeve near the first air inlet 1-1 to close the end, and a grid is provided at one end of the gap between the first cylindrical baffle plate 3 and the inner sleeve near the first air outlet 1-2, so that the fuel gas enters the second flow channel from the grid, enters the catalytic combustion catalyst through each hole, and then flows horizontally, and is then discharged from the side of the catalytic combustion catalyst layer near the first air outlet 1-2, and is discharged from the first air outlet 1-2.

[0093] Furthermore, the total area of ​​the holes accounts for 10%-90% of the area of ​​the first cylindrical baffle 3, and the hole diameter is 0.5mm-25mm. The hole diameter is related to the flow rate of the fuel gas entering the catalytic combustion catalyst, and then to the combustion catalytic efficiency and heat generation; while the density of the holes is related to the smooth discharge of the gas entering the first flow channel. By setting the density and hole diameter within this numerical range, the gas entering the first flow channel can be discharged smoothly while ensuring a certain amount of heat generation, avoiding safety hazards.

[0094] Example 4

[0095] like Figure 2 As shown, this embodiment provides an autothermal ammonia decomposition reactor, which is different from the autothermal ammonia decomposition reactor provided in Example 3 in that:

[0096] The inner sleeve 2 is filled with a catalytic combustion catalyst, and the gap between the inner sleeve 2 and the outer sleeve 1 is filled with an ammonia decomposition catalyst;

[0097] The second air inlet 2-1 is suitable for communicating with fuel gas, and the fuel gas is suitable for exothermic reaction with the catalytic combustion catalyst.

[0098] Example 5

[0099] like Figure 3 As shown, this embodiment provides an autothermal ammonia decomposition reactor, which is different from the autothermal ammonia decomposition reactor provided in Example 1 in that:

[0100] An air intake pipe 4 is arranged inside the inner sleeve 2. The air intake pipe 4 is provided with a plurality of holes. One end of the air intake pipe 4 is connected to the second air intake port 2-1, and the opposite end is sealed. After ammonia enters the air intake pipe 4 from the second air intake port 2-1, it enters the ammonia decomposition catalyst through the holes to participate in the reaction. The arrangement of the air intake pipe 4 and the holes increases the lateral flow of ammonia, thereby increasing the flow path of ammonia, thereby increasing the ammonia decomposition efficiency.

[0101] Specifically, a partition plate 14 is provided at one end of the intake pipe 4 away from the second intake port 2-1 to close the end pipe opening. After ammonia enters the intake pipe 4 from the second intake port 2-1, it enters the ammonia decomposition catalyst through the hole and flows horizontally, and then is discharged from the side of the ammonia decomposition catalyst layer close to the second outlet 2-2, enters the cavity, and is then discharged from the second outlet 2-2.

[0102] Furthermore, the total area of ​​the holes accounts for 10% to 90% of the area of ​​the intake pipe 4, and the hole diameter is 0.5 mm to 25 mm. The hole diameter is related to the flow rate of ammonia entering the ammonia decomposition catalyst layer, and then to the ammonia decomposition efficiency; while the hole density is related to the smooth discharge of the gas entering the intake pipe 4. By setting the density and hole diameter within this numerical range, the gas entering the intake pipe 4 can be discharged smoothly while ensuring a certain ammonia decomposition efficiency, avoiding safety hazards.

[0103] Example 6

[0104] like Figure 3 As shown, this embodiment provides an autothermal ammonia decomposition reactor, which is different from the autothermal ammonia decomposition reactor provided in Example 5 in that:

[0105] The inner sleeve 2 is filled with a catalytic combustion catalyst, and the gap between the inner sleeve 2 and the outer sleeve 1 is filled with an ammonia decomposition catalyst;

[0106] The second air inlet 2-1 is suitable for communicating with fuel gas, and the fuel gas is suitable for exothermic reaction with the catalytic combustion catalyst.

[0107] Example 7

[0108] like Figure 4 As shown, this embodiment provides an autothermal ammonia decomposition reactor, which is different from the autothermal ammonia decomposition reactor provided in Example 3 in that:

[0109] An air intake pipe 4 is arranged inside the inner sleeve 2. The air intake pipe 4 is provided with a plurality of holes. One end of the air intake pipe 4 is connected to the second air intake port 2-1, and the opposite end is sealed. After ammonia enters the air intake pipe 4 from the second air intake port 2-1, it enters the ammonia decomposition catalyst through the holes to participate in the reaction. The arrangement of the air intake pipe 4 and the holes increases the lateral flow of ammonia, thereby increasing the flow path of ammonia, thereby increasing the ammonia decomposition efficiency.

[0110] Specifically, a partition plate 14 is provided at one end of the intake pipe 4 away from the second intake port 2-1 to close the end pipe opening. After ammonia enters the intake pipe 4 from the second intake port 2-1, it enters the ammonia decomposition catalyst through the hole and flows horizontally, and then is discharged from the side of the ammonia decomposition catalyst layer close to the second outlet 2-2, enters the cavity, and is then discharged from the second outlet 2-2.

[0111] Furthermore, the area of ​​the holes accounts for 10% to 90% of the area of ​​the intake pipe 4, and the hole diameter is 0.5 mm to 25 mm. The hole diameter is related to the flow rate of ammonia entering the ammonia decomposition catalyst layer, and then to the ammonia decomposition efficiency; while the hole density is related to the smooth discharge of the gas entering the intake pipe 4. By setting the density and hole diameter within this numerical range, the gas entering the intake pipe 4 can be discharged smoothly while ensuring a certain ammonia decomposition efficiency, avoiding safety hazards.

[0112] Example 8

[0113] like Figure 4 As shown, this embodiment provides an autothermal ammonia decomposition reactor, which is different from the autothermal ammonia decomposition reactor provided in Example 7 in that:

[0114] The inner sleeve 2 is filled with a catalytic combustion catalyst, and the gap between the inner sleeve 2 and the outer sleeve 1 is filled with an ammonia decomposition catalyst;

[0115] The second air inlet 2-1 is suitable for communicating with fuel gas, and the fuel gas is suitable for exothermic reaction with the catalytic combustion catalyst.

[0116] Example 9

[0117] like Figure 5 As shown, this embodiment provides an autothermal ammonia decomposition reactor, which is different from the autothermal ammonia decomposition reactor provided in Example 1 in that:

[0118] A second cylindrical baffle 5 is longitudinally arranged inside the inner sleeve 2, and the second cylindrical baffle 5 and the inner sleeve 2 have the same central axis. The second cylindrical baffle 5 is filled with a ruthenium-based ammonia decomposition catalyst, and the gap between the second cylindrical baffle 5 and the inner sleeve 2 is filled with a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst. It should be understood that the catalyst filled in the second cylindrical baffle 5 includes but is not limited to a ruthenium-based ammonia decomposition catalyst, and the catalyst filled in the gap between the second cylindrical baffle 5 and the inner sleeve 2 includes but is not limited to a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst, and it is only necessary to make the use temperature of the ammonia decomposition catalyst filled in the second cylindrical baffle 5 lower than the use temperature of the ammonia decomposition catalyst filled in the gap between the second cylindrical baffle 5 and the inner sleeve 2.

[0119] The process of ammonia decomposition requires the absorption of heat, which causes the temperature in the inner sleeve 2 to gradually decrease along the wall of the inner sleeve 2 pointing to the direction of the second cylindrical baffle 5. When the reactor is running, a "reaction-diffusion" process occurs inside the catalyst particles. Due to the existence of the diffusion resistance of the components inside the particles, there is a component concentration gradient inside the catalyst particles. When the diffusion resistance inside the particles has a great influence, the reactant components cannot effectively diffuse into the catalyst particles, resulting in a decrease in the catalyst utilization rate. The influence of the diffusion rate of the components in the catalyst particles on the catalyst performance is usually expressed by the efficiency factor. Theoretical analysis shows that the efficiency factor of the catalyst particles usually decreases monotonically with the increase of the Thiele modulus. Factors such as catalyst particle size, pore size, porosity, and ammonia decomposition conversion rate on the particle surface all have an impact on the Thiele modulus, which is specifically manifested as follows: as the catalyst particle size increases, the Thiele modulus increases; as the pore size in the particle increases, the Thiele modulus decreases; as the porosity in the particle increases, the Thiele modulus decreases; Based on the above analysis, it can be seen that when loading the catalyst in the reactor, catalysts with different active components can be used in different areas, or catalysts with the same active components but different particle sizes, porosities or pore sizes can be used in different areas, so that the catalyst performance is adapted to the bed environment.

[0120] When the temperature span is large, in order to improve the utilization rate of the ammonia decomposition catalyst, the ammonia decomposition catalyst is a nickel-based ammonia decomposition catalyst, an iron-based ammonia decomposition catalyst, or a ruthenium-based ammonia decomposition catalyst in the direction of the second cylindrical baffle 5 along the wall of the inner sleeve 2, and different catalysts are separated by the second cylindrical baffle 5. This is because the reaction temperature of the Fe-based decomposition catalyst or the Ni-based decomposition catalyst is about 850°C, and the reaction temperature of the Ru-based catalyst is about 500°C, so that the use temperature of the catalyst is adapted to the temperature in the autothermal ammonia decomposition reactor, thereby improving the utilization rate of the ammonia decomposition catalyst. Specifically, the size of the second cylindrical baffle 5 can be adjusted as needed to adapt the setting mode of the ammonia decomposition catalyst to the reaction environment.

[0121] Furthermore, in order to improve the ammonia decomposition efficiency, a plurality of second cylindrical baffles may be longitudinally arranged inside the inner sleeve, and the second cylindrical baffles and the inner sleeve have the same central axis to form a plurality of ammonia decomposition catalyst layers having the same central axis, wherein the applicable temperature of the ammonia decomposition catalyst decreases layer by layer along the direction from the inner sleeve wall to the central axis; for example, medium- and high-temperature ammonia decomposition catalysts such as iron-based are filled near the inner sleeve wall, medium- and low-temperature ammonia decomposition catalysts such as ruthenium-based are filled at the central axis, and medium-temperature ammonia decomposition catalysts such as nickel-based are filled in the middle area between the above two ammonia decomposition catalyst layers.

[0122] As another embodiment, when the temperature span along the direction of the inner sleeve wall pointing to the central axis is small, the same catalyst, such as Ru-based decomposition catalyst, Fe-based decomposition catalyst or Ni-based decomposition catalyst, can be used, and the particle size, pores and porosity of different catalyst layers in the pipeline are adjusted to achieve the purpose of improving the utilization rate of the catalyst. Specifically, a plurality of second cylindrical baffles are longitudinally arranged inside the inner sleeve, and the second cylindrical baffles and the inner sleeve have the same central axis to form a plurality of ammonia decomposition catalyst layers with the same central axis, wherein, along the direction from the inner sleeve to the central axis, the particle size of the ammonia decomposition catalyst gradually decreases or increases, and the ratio of the particle size of the latter layer of ammonia decomposition catalyst to the particle size of the previous layer of ammonia decomposition catalyst is 0.25-4; and / or, the pores of the ammonia decomposition catalyst gradually decrease or increase, and the pores are 2nm-4000nm; and / or, the porosity of the ammonia decomposition catalyst gradually decreases or increases, and the porosity is 0.1-0.7. It should be understood that the filling method of the ammonia decomposition catalyst can be adjusted as needed, and is not limited here.

[0123] In addition, in order to improve the ammonia decomposition efficiency, the particle size and / or pores and / or porosity of different catalyst layers in the pipeline can be adjusted while reducing the applicable temperature of each ammonia decomposition catalyst layer from the inner sleeve to the outer sleeve, so that the self-heating ammonia decomposition reactor provided in this embodiment can adapt to different environments.

[0124] It should be understood that the autothermal ammonia decomposition reactor provided in this embodiment can also be provided with a first cylindrical baffle 3 in the radial direction of the gap between the inner sleeve 2 and the outer sleeve 1 as needed, so as to further improve the ammonia decomposition efficiency by increasing the heat generation of the catalytic combustion catalyst layer. Figure 6 As shown, the autothermal ammonia decomposition reactor provided in this embodiment is provided with the first cylindrical baffle plate 3 provided in embodiment 3. The arrangement of the first cylindrical baffle plate 3 is the same as that in embodiment 3, and will not be described in detail here.

[0125] Example 10

[0126] like Figure 7 As shown, this embodiment provides an autothermal ammonia decomposition reactor, which is different from the autothermal ammonia decomposition reactor provided in Example 1 in that:

[0127] A first grid plate 6 is provided in the inner sleeve 2, and the first grid plate 6 abuts against the inner wall of the inner sleeve 2, wherein a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst is filled between the second air inlet 2-1 and the first grid plate 6, and a ruthenium-based ammonia decomposition catalyst is filled between the second air outlet 2-2 and the first grid plate 6. It should be understood that the catalyst filled between the second air outlet 2-2 and the first grid plate 6 includes but is not limited to a ruthenium-based ammonia decomposition catalyst, and the catalyst filled between the second air inlet 2-1 and the first grid plate 6 includes but is not limited to a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst, and it is only necessary to make the use temperature of the ammonia decomposition catalyst filled between the second air outlet 2-2 and the first grid plate 6 lower than the use temperature of the ammonia decomposition catalyst filled between the second air inlet 2-1 and the first grid plate 6.

[0128] The decomposition of ammonia requires the absorption of heat, which causes the temperature to gradually decrease along the direction of ammonia flow. When the reactor is running, a "reaction-diffusion" process occurs inside the catalyst particles. Due to the diffusion resistance of the components inside the particles, there is a component concentration gradient inside the catalyst particles. When the diffusion resistance inside the particles has a great influence, the reactant components cannot effectively diffuse into the catalyst particles, resulting in a decrease in catalyst utilization. The effect of the diffusion rate of the components inside the catalyst particles on the catalyst performance is usually expressed by the efficiency factor. Theoretical analysis shows that the efficiency factor of the catalyst particles usually decreases monotonically with the increase of the Thiele modulus. Factors such as catalyst particle size, pore size, porosity, and ammonia decomposition conversion rate on the particle surface all have an impact on the Thiele modulus, which is specifically manifested as follows: as the catalyst particle size increases, the Thiele modulus increases; as the pore size in the particle increases, the Thiele modulus decreases; as the porosity in the particle increases, the Thiele modulus decreases; Based on the above analysis, it can be seen that when loading the catalyst in the reactor, catalysts with different active components can be used in different areas, or catalysts with the same active components but different particle sizes, porosities or pore sizes can be used in different areas, so that the catalyst performance is adapted to the bed environment.

[0129] When the temperature span is large, in order to improve the utilization rate of the ammonia decomposition catalyst, along the direction of ammonia flow, the ammonia decomposition catalyst is a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst, and a ruthenium-based ammonia decomposition catalyst, and different catalysts are separated by the first grid plate 6. This is because the reaction temperature of the Fe-based decomposition catalyst or the Ni-based decomposition catalyst is about 850°C, and the reaction temperature of the Ru-based catalyst is about 500°C, so that the use temperature of the catalyst is adapted to the temperature in the autothermal ammonia decomposition reactor, thereby improving the utilization rate of the ammonia decomposition catalyst. Specifically, the setting position of the first grid plate 6 can be adjusted as needed to make the setting mode of the ammonia decomposition catalyst adapted to the reaction environment.

[0130] Furthermore, in order to improve the ammonia decomposition efficiency, a plurality of first grid plates may be arranged in the inner sleeve, and the first grid plates are respectively in contact with the inner wall of the inner sleeve to form a plurality of ammonia decomposition catalyst layers inside the inner sleeve, wherein the applicable temperature of the ammonia decomposition catalyst decreases layer by layer along the direction of gas flow in the inner sleeve; for example, medium- and high-temperature ammonia decomposition catalysts such as iron-based, medium-temperature ammonia decomposition catalysts such as nickel-based, and medium- and low-temperature ammonia decomposition catalysts such as ruthenium-based are sequentially arranged in the inner sleeve along the direction of gas flow in the inner sleeve.

[0131] As another embodiment, when the temperature span along the direction of ammonia flow is small, the same catalyst, such as Ru-based decomposition catalyst, Fe-based decomposition catalyst or Ni-based decomposition catalyst, can be used, and the particle size, pores and porosity of different catalyst layers in the pipeline are adjusted to achieve the purpose of improving the utilization rate of the catalyst. Specifically, a plurality of first grid plates are arranged in the inner sleeve, and the first grid plates are respectively abutted against the inner wall of the inner sleeve to form a plurality of ammonia decomposition catalyst layers inside the inner sleeve, wherein, along the direction of gas flow in the inner sleeve, the particle size of the ammonia decomposition catalyst gradually decreases or increases, and the ratio of the particle size of the latter layer of ammonia decomposition catalyst to the particle size of the previous layer of ammonia decomposition catalyst is 0.25-4; and / or, the pores of the ammonia decomposition catalyst gradually decrease or increase, and the pores are 2nm-4000nm; and / or, the porosity of the ammonia decomposition catalyst gradually decreases or increases, and the porosity is 0.1-0.7. It should be understood that the filling method of the ammonia decomposition catalyst can be adjusted as needed, and is not limited here.

[0132] In addition, in order to improve the ammonia decomposition efficiency, the particle size and / or pores and / or porosity of different catalyst layers in the pipeline can be adjusted while reducing the applicable temperature of each ammonia decomposition catalyst layer along the direction of gas flow in the inner sleeve layer, so that the self-heating ammonia decomposition reactor provided in this embodiment can adapt to different environments.

[0133] It should be understood that the autothermal ammonia decomposition reactor provided in this embodiment can also be provided with a plurality of first cylindrical baffles 3 in the radial direction of the gap between the inner sleeve 2 and the outer sleeve 1 as required, so as to further improve the ammonia decomposition efficiency by increasing the heat generation of the catalytic combustion catalyst layer. Figure 8 As shown, the autothermal ammonia decomposition reactor provided in this embodiment is provided with the first cylindrical baffle plate 3 provided in embodiment 3. The arrangement of the first cylindrical baffle plate 3 is the same as that in embodiment 3, and will not be described in detail here.

[0134] It should be understood that the autothermal ammonia decomposition reactor provided in this embodiment can also be provided with an air inlet pipe 4 inside the inner sleeve 2 as needed, so as to further improve the ammonia decomposition efficiency by increasing the flow path of ammonia in the ammonia decomposition catalyst layer. Fig. 9As shown, the autothermal ammonia decomposition reactor provided in this embodiment is provided with the air inlet pipe 4 provided in embodiment 5. The arrangement of the air inlet pipe 4 is the same as that in embodiment 5, and will not be described in detail here.

[0135] It should be understood that the autothermal ammonia decomposition reactor provided in this embodiment can also be provided with a plurality of first cylindrical baffles 3 radially disposed in the gap between the inner sleeve 2 and the outer sleeve 1 as required, and an air inlet pipe 4 is also provided inside the inner sleeve 2, that is, Fig.10 As shown, the autothermal ammonia decomposition reactor provided in this embodiment is provided with the first cylindrical baffle plate 3 provided in embodiment 3 and the air inlet pipe 4 provided in embodiment 5. The first cylindrical baffle plate 3 is provided in the same manner as in embodiment 3, and the air inlet pipe 4 is provided in the same manner as in embodiment 5, which will not be repeated here.

[0136] Embodiment 11

[0137] This embodiment provides an autothermal ammonia decomposition reactor, which is different from the autothermal ammonia decomposition reactor provided in Example 2 in that:

[0138] A first grid plate 6 is provided in the gap between the inner sleeve 2 and the outer sleeve 1, and the first grid plate 6 abuts against the outer wall of the inner sleeve 2 and the inner wall of the outer sleeve 1, respectively, wherein a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst is filled between the first air inlet 1-1 and the first grid plate 6, and a ruthenium-based ammonia decomposition catalyst is filled between the first air outlet 1-2 and the first grid plate 6. It should be understood that the catalyst filled between the first air outlet 1-2 and the first grid plate 6 includes but is not limited to a ruthenium-based ammonia decomposition catalyst, and the catalyst filled between the first air inlet 1-1 and the first grid plate 6 includes but is not limited to a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst, and it is only necessary to make the use temperature of the ammonia decomposition catalyst filled between the first air outlet 1-2 and the first grid plate 6 lower than the use temperature of the ammonia decomposition catalyst filled between the first air inlet 1-1 and the first grid plate 6.

[0139] The decomposition of ammonia requires the absorption of heat, which causes the temperature to gradually decrease along the direction of ammonia flow. When the reactor is running, a "reaction-diffusion" process occurs inside the catalyst particles. Due to the diffusion resistance of the components inside the particles, there is a component concentration gradient inside the catalyst particles. When the diffusion resistance inside the particles has a great influence, the reactant components cannot effectively diffuse into the catalyst particles, resulting in a decrease in catalyst utilization. The effect of the diffusion rate of the components inside the catalyst particles on the catalyst performance is usually expressed by the efficiency factor. Theoretical analysis shows that the efficiency factor of the catalyst particles usually decreases monotonically with the increase of the Thiele modulus. Factors such as catalyst particle size, pore size, porosity, and ammonia decomposition conversion rate on the particle surface all have an impact on the Thiele modulus, which is specifically manifested as follows: as the catalyst particle size increases, the Thiele modulus increases; as the pore size in the particle increases, the Thiele modulus decreases; as the porosity in the particle increases, the Thiele modulus decreases; Based on the above analysis, it can be seen that when loading the catalyst in the reactor, catalysts with different active components can be used in different areas, or catalysts with the same active components but different particle sizes, porosities or pore sizes can be used in different areas, so that the catalyst performance is adapted to the bed environment.

[0140] When the temperature span is large, in order to improve the utilization rate of the ammonia decomposition catalyst, along the direction of ammonia flow, the ammonia decomposition catalyst is a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst, and a ruthenium-based ammonia decomposition catalyst, and different catalysts are separated by the first grid plate 6. This is because the reaction temperature of the Fe-based decomposition catalyst or the Ni-based decomposition catalyst is about 850°C, and the reaction temperature of the Ru-based catalyst is about 500°C, so that the use temperature of the catalyst is adapted to the temperature in the autothermal ammonia decomposition reactor, thereby improving the utilization rate of the ammonia decomposition catalyst. Specifically, the setting position of the first grid plate 6 can be adjusted as needed to make the setting mode of the ammonia decomposition catalyst adapted to the reaction environment.

[0141] Furthermore, in order to improve the ammonia decomposition efficiency, a plurality of first grid plates may be arranged at intervals in the gap between the inner sleeve and the outer sleeve along the direction of ammonia flow, so that a plurality of ammonia decomposition catalyst layers are formed in the gap between the inner sleeve and the outer sleeve, wherein the applicable temperature of the ammonia decomposition catalyst decreases layer by layer along the direction of ammonia flow; for example, medium- and high-temperature ammonia decomposition catalysts such as iron-based, medium-temperature ammonia decomposition catalysts such as nickel-based, and medium- and low-temperature ammonia decomposition catalysts such as ruthenium-based are sequentially arranged in the inner sleeve along the direction of ammonia flow in the gap between the inner sleeve and the outer sleeve.

[0142] As another embodiment, when the temperature span along the direction of ammonia flow is small, the same catalyst, such as Ru-based decomposition catalyst, Fe-based decomposition catalyst or Ni-based decomposition catalyst, can be used, and the particle size, pores and porosity of different catalyst layers in the pipeline are adjusted to achieve the purpose of improving the utilization rate of the catalyst. Specifically, a plurality of first grid plates are provided in the gap between the inner sleeve and the outer sleeve, and the first grid plates are respectively abutted against the outer wall of the inner sleeve and the inner wall of the outer sleeve, so that a plurality of ammonia decomposition catalyst layers are formed in the gap between the inner sleeve and the outer sleeve, wherein, along the direction of gas flow, the particle size of the ammonia decomposition catalyst gradually decreases or increases, and the ratio of the particle size of the latter layer of ammonia decomposition catalyst to the particle size of the previous layer of ammonia decomposition catalyst is 0.25-4; and / or, the pores of the ammonia decomposition catalyst gradually decrease or increase, and the pores are 2nm-4000nm; and / or, the porosity of the ammonia decomposition catalyst gradually decreases or increases, and the porosity is 0.1-0.7. It should be understood that the filling method of the ammonia decomposition catalyst can be adjusted as needed, and is not limited here.

[0143] In addition, in order to improve the ammonia decomposition efficiency, the particle size and / or pores and / or porosity of different catalyst layers in the pipeline can be adjusted while the gap between the inner sleeve and the outer sleeve is reduced layer by layer along the direction of gas flow so that the applicable temperature of each layer of the ammonia decomposition catalyst layer can be reduced layer by layer, so that the self-heating ammonia decomposition reactor provided in this embodiment can adapt to different environments.

[0144] It should be understood that the autothermal ammonia decomposition reactor provided in this embodiment can also be provided with a plurality of first cylindrical baffles 3 in the radial direction of the gap between the inner sleeve 2 and the outer sleeve 1 as required, so as to further improve the ammonia decomposition efficiency by increasing the heat generation of the catalytic combustion catalyst layer. Fig.11 As shown, the autothermal ammonia decomposition reactor provided in this embodiment is provided with the first cylindrical baffle plate 3 provided in embodiment 3. The arrangement of the first cylindrical baffle plate 3 is the same as that in embodiment 3, and will not be described in detail here.

[0145] Example 12

[0146] like Fig.12 As shown, this embodiment provides an autothermal ammonia decomposition reactor, which is different from the autothermal ammonia decomposition reactor provided in Example 2 in that:

[0147] A second cylindrical baffle 5 is longitudinally arranged in the gap between the inner sleeve 2 and the outer sleeve 1, and the second cylindrical baffle and the inner sleeve have the same central axis, wherein the gap between the second cylindrical baffle 5 and the inner sleeve 2 is filled with a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst, and the gap between the second cylindrical baffle 5 and the outer sleeve 1 is filled with a ruthenium-based ammonia decomposition catalyst. It should be understood that the catalyst filled in the gap between the second cylindrical baffle 5 and the outer sleeve 1 includes but is not limited to a ruthenium-based ammonia decomposition catalyst, and the catalyst filled in the gap between the second cylindrical baffle 5 and the inner sleeve 2 includes but is not limited to a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst, and it is only necessary to make the use temperature of the ammonia decomposition catalyst filled in the gap between the second cylindrical baffle 5 and the outer sleeve 1 lower than the use temperature of the ammonia decomposition catalyst filled in the gap between the second cylindrical baffle 5 and the inner sleeve 2.

[0148] The process of ammonia decomposition requires the absorption of heat, which causes the temperature to gradually decrease along the direction from the inner sleeve 2 to the outer sleeve 1. When the reactor is running, a "reaction-diffusion" process occurs inside the catalyst particles. Due to the diffusion resistance of the components inside the particles, there is a component concentration gradient inside the catalyst particles. When the diffusion resistance inside the particles has a great influence, the reactant components cannot effectively diffuse into the catalyst particles, resulting in a decrease in catalyst utilization. The influence of the diffusion rate of the components inside the catalyst particles on the catalyst performance is usually expressed by the efficiency factor. Theoretical analysis shows that the efficiency factor of the catalyst particles usually decreases monotonically with the increase of the Thiele modulus. Factors such as catalyst particle size, pore size, porosity, and ammonia decomposition conversion rate on the particle surface all have an impact on the Thiele modulus, which is specifically manifested as follows: as the catalyst particle size increases, the Thiele modulus increases; as the pore size in the particle increases, the Thiele modulus decreases; as the porosity in the particle increases, the Thiele modulus decreases; Based on the above analysis, it can be seen that when loading the catalyst in the reactor, catalysts with different active components can be used in different areas, or catalysts with the same active components but different particle sizes, porosities or pore sizes can be used in different areas, so that the catalyst performance is adapted to the bed environment.

[0149] When the temperature span is large, in order to improve the utilization rate of the ammonia decomposition catalyst, along the direction from the inner sleeve 2 to the outer sleeve 1, the ammonia decomposition catalyst is a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst, and a ruthenium-based ammonia decomposition catalyst, respectively, and different catalysts are separated by a second cylindrical baffle 5. This is because the reaction temperature of the Fe-based decomposition catalyst or the Ni-based decomposition catalyst is about 850°C, and the reaction temperature of the Ru-based catalyst is about 500°C, so that the use temperature of the catalyst is adapted to the temperature in the autothermal ammonia decomposition reactor, thereby improving the utilization rate of the ammonia decomposition catalyst. Specifically, the size of the second cylindrical baffle 5 can be adjusted as needed to adapt the setting mode of the ammonia decomposition catalyst to the reaction environment.

[0150] Furthermore, in order to improve the ammonia decomposition efficiency, a plurality of second cylindrical baffles may be longitudinally arranged in the gap between the inner sleeve and the outer sleeve, and the second cylindrical baffles and the inner sleeve have the same central axis to form a plurality of ammonia decomposition catalyst layers having the same central axis, wherein the applicable temperature of the ammonia decomposition catalyst decreases layer by layer along the direction from the inner sleeve to the outer sleeve; for example, medium- and high-temperature ammonia decomposition catalysts such as iron-based are filled near the inner sleeve, medium- and low-temperature ammonia decomposition catalysts such as ruthenium-based are filled near the outer sleeve, and medium-temperature ammonia decomposition catalysts such as nickel-based are filled in the middle area.

[0151] As another embodiment, when the temperature span along the direction from the inner sleeve to the outer sleeve is small, the same catalyst, such as Ru-based decomposition catalyst, Fe-based decomposition catalyst or Ni-based decomposition catalyst, can be used, and the particle size, pores and porosity of different catalyst layers in the pipeline are adjusted to achieve the purpose of improving the utilization rate of the catalyst. Specifically, a plurality of second cylindrical baffles are longitudinally arranged in the gap between the inner sleeve and the outer sleeve, and the second cylindrical baffles and the inner sleeve have the same central axis to form a plurality of ammonia decomposition catalyst layers with the same central axis, wherein, along the direction from the inner sleeve to the outer sleeve, the particle size of the ammonia decomposition catalyst gradually decreases or increases, and the ratio of the particle size of the latter layer of ammonia decomposition catalyst to the particle size of the previous layer of ammonia decomposition catalyst is 0.25-4; and / or, the pores of the ammonia decomposition catalyst gradually decrease or increase, and the pores are 2nm-4000nm; and / or, the porosity of the ammonia decomposition catalyst gradually decreases or increases, and the porosity is 0.1-0.7. It should be understood that the filling method of the ammonia decomposition catalyst can be adjusted as needed, and is not limited here.

[0152] In addition, in order to improve the ammonia decomposition efficiency, the particle size and / or pores and / or porosity of different catalyst layers in the pipeline can be adjusted while reducing the applicable temperature of each ammonia decomposition catalyst layer from the inner sleeve to the outer sleeve, so that the self-heating ammonia decomposition reactor provided in this embodiment can adapt to different environments.

[0153] It should be understood that the autothermal ammonia decomposition reactor provided in this embodiment can also be provided with an air inlet pipe 4 inside the inner sleeve 2 as required, so as to further improve the ammonia decomposition efficiency by increasing the heat generation of the catalytic combustion catalyst layer. Fig.13 As shown, the autothermal ammonia decomposition reactor provided in this embodiment is provided with the air inlet pipe 4 provided in embodiment 6. The arrangement of the air inlet pipe 4 is the same as that in embodiment 6, and will not be described in detail here.

[0154] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. An autothermal ammonia decomposition reactor, characterized in that: include: The outer sleeve (1) comprises a first air inlet (1-1) and a first air outlet (1-2) respectively arranged at two ends thereof; An inner sleeve (2) is arranged inside the outer sleeve (1), the inner sleeve (2) comprises a second air inlet (2-1) and a second air outlet (2-2) which are arranged at two ends thereof and extend to the outside of the outer sleeve (1), the inner sleeve (2) is filled with a first catalyst, and the gap between the inner sleeve (2) and the outer sleeve (1) is filled with a second catalyst, wherein one of the first catalyst and the second catalyst is an ammonia decomposition catalyst, and the other is a catalytic combustion catalyst; The first air inlet (1-1) or the second air inlet (2-1) is suitable for connecting with fuel gas, and the fuel gas is suitable for exothermic reaction with the catalytic combustion catalyst; A first cylindrical baffle (3) is radially arranged in the gap between the inner sleeve (2) and the outer sleeve (1), the first cylindrical baffle (3) and the inner sleeve have the same central axis, a plurality of holes are arranged on a side of the first cylindrical baffle (3) close to the inner sleeve, the gap between the first cylindrical baffle (3) and the outer sleeve forms a first flow channel, the gap between the first cylindrical baffle (3) and the inner sleeve forms a second flow channel, the first flow channel is open at one end close to the first air inlet, and is closed at one end close to the first air outlet, the second flow channel is closed at one end close to the first air inlet, and is open at one end close to the first air outlet; An air intake pipe (4) is arranged inside the inner sleeve (2), the air intake pipe (4) is provided with a plurality of holes, one end of the air intake pipe (4) is connected to the second air intake port (2-1), and the opposite end is sealed.

2. The autothermal ammonia decomposition reactor according to claim 1, characterized in that: The catalytic combustion catalyst is a hydrogen catalytic combustion catalyst or an ammonia catalytic combustion catalyst, and the hydrogen catalytic combustion catalyst is MgAl2O4, Mn-Co-Cu-Fe-Ni / γ-Al2O3 / cordierite, Pt / γ-Al2O3 / cordierite, Pt / Ce x Zr 1－ x O2 / γ-Al2O3, the ammonia catalytic combustion catalyst is Fe2O3, V2O5, Cr2O3, MoO x , WO x At least one of; The ammonia decomposition catalyst is a ruthenium-based ammonia decomposition catalyst, an iron-based ammonia decomposition catalyst or a nickel-based ammonia decomposition catalyst.

3. The autothermal ammonia decomposition reactor according to claim 1, characterized in that: An air intake pipe (4) is arranged inside the inner sleeve (2), the air intake pipe (4) is provided with a plurality of holes, one end of the air intake pipe (4) is connected to the second air intake port (2-1), and the opposite end is sealed.

4. The autothermal ammonia decomposition reactor according to claim 1 or 2, characterized in that: A second cylindrical baffle (5) is longitudinally arranged inside the inner sleeve (2); the second cylindrical baffle and the inner sleeve have the same central axis; the second cylindrical baffle (5) is filled with a ruthenium-based ammonia decomposition catalyst; and the gap between the second cylindrical baffle (5) and the inner sleeve (2) is filled with a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst.

5. The autothermal ammonia decomposition reactor according to claim 1 or 2, characterized in that: A plurality of second cylindrical baffles (5) are longitudinally arranged inside the inner sleeve (2), and the second cylindrical baffles and the inner sleeve have the same central axis to form a plurality of ammonia decomposition catalyst layers having the same central axis, wherein, in the direction from the inner sleeve (2) to the central axis, The applicable temperature of the ammonia decomposition catalyst decreases layer by layer; and / or, The particle size of the ammonia decomposition catalyst gradually decreases or increases, and the ratio of the particle size of the ammonia decomposition catalyst in the latter layer to that in the former layer is 0.25-4; and / or, The pores of the ammonia decomposition catalyst gradually decrease or gradually increase, and the pores are 2nm-4000nm; and / or, The porosity of the ammonia decomposition catalyst gradually decreases or increases, and the porosity is 0.1-0.

7.

6. The autothermal ammonia decomposition reactor according to any one of claims 1 to 3, characterized in that: A first grid plate (6) is arranged in the inner sleeve (2), and the first grid plate (6) abuts against the inner wall of the inner sleeve (2), wherein a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst is filled between the second air inlet (2-1) and the first grid plate (6), and a ruthenium-based ammonia decomposition catalyst is filled between the second air outlet (2-2) and the first grid plate (6).

7. The autothermal ammonia decomposition reactor according to any one of claims 1 to 3, characterized in that: A plurality of first grid plates (6) are arranged in the inner sleeve (2), and the first grid plates (6) are respectively in contact with the inner wall of the inner sleeve (2) so as to form a plurality of ammonia decomposition catalyst layers inside the inner sleeve (2), wherein, along the direction of gas flow in the inner sleeve (2), The applicable temperature of the ammonia decomposition catalyst decreases layer by layer; and / or, The particle size of the ammonia decomposition catalyst gradually decreases or increases, and the ratio of the particle size of the ammonia decomposition catalyst in the latter layer to that in the former layer is 0.25-4; and / or, The pores of the ammonia decomposition catalyst gradually decrease or gradually increase, and the pores are 2nm-4000nm; and / or, The porosity of the ammonia decomposition catalyst gradually decreases or increases, and the porosity is 0.1-0.

7.

8. The autothermal ammonia decomposition reactor according to any one of claims 1 to 3, characterized in that: A first grid plate (6) is provided in the gap between the inner sleeve (2) and the outer sleeve (1), and the first grid plate (6) abuts against the outer wall of the inner sleeve (2) and the inner wall of the outer sleeve (1), respectively; a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst is filled between the first air inlet (1-1) and the first grid plate (6), and a ruthenium-based ammonia decomposition catalyst is filled between the first air outlet (1-2) and the first grid plate (6).

9. The autothermal ammonia decomposition reactor according to any one of claims 1 to 3, characterized in that: A plurality of first grid plates (6) are provided in the gap between the inner sleeve (2) and the outer sleeve (1), and the first grid plates (6) are respectively in contact with the outer wall of the inner sleeve (2) and the inner wall of the outer sleeve (1), so that a plurality of ammonia decomposition catalyst layers are formed in the gap between the inner sleeve (2) and the outer sleeve (1), wherein the gap between the inner sleeve (2) and the outer sleeve (1) is along the direction of gas flow. The applicable temperature of the ammonia decomposition catalyst decreases layer by layer; and / or, The particle size of the ammonia decomposition catalyst gradually decreases or increases, and the ratio of the particle size of the ammonia decomposition catalyst in the latter layer to that in the former layer is 0.25-4; and / or, The pores of the ammonia decomposition catalyst gradually decrease or gradually increase, and the pores are 2nm-4000nm; and / or, The porosity of the ammonia decomposition catalyst gradually decreases or increases, and the porosity is 0.1-0.

7.

10. The autothermal ammonia decomposition reactor according to claim 1 or 2, characterized in that: A second cylindrical baffle (5) is longitudinally arranged in the gap between the inner sleeve (2) and the outer sleeve (1); the second cylindrical baffle and the inner sleeve have the same central axis, wherein the gap between the second cylindrical baffle (5) and the inner sleeve (2) is filled with a nickel-based ammonia decomposition catalyst or an iron-based ammonia decomposition catalyst, and the gap between the second cylindrical baffle (5) and the outer sleeve (1) is filled with a ruthenium-based ammonia decomposition catalyst.

11. The autothermal ammonia decomposition reactor according to claim 1 or 2, characterized in that: A plurality of second cylindrical baffles (5) are longitudinally arranged in the gap between the inner sleeve (2) and the outer sleeve (1), and the second cylindrical baffles and the inner sleeve have the same central axis to form a plurality of ammonia decomposition catalyst layers having the same central axis, wherein, along the direction from the inner sleeve (2) to the outer sleeve (1), The applicable temperature of the ammonia decomposition catalyst decreases layer by layer; and / or, The particle size of the ammonia decomposition catalyst gradually decreases or increases, and the ratio of the particle size of the ammonia decomposition catalyst in the latter layer to that in the former layer is 0.25-4; and / or, The pores of the ammonia decomposition catalyst gradually decrease or gradually increase, and the pores are 2nm-4000nm; and / or, The porosity of the ammonia decomposition catalyst gradually decreases or increases, and the porosity is 0.1-0.7.

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