Process for producing synthesis gas products containing hydrogen

Abstract

The present invention relates to a reactor (1) for producing a synthesis gas product comprising hydrogen from an ammonia feedstock stream, the reactor comprising: - a first catalyst bed (5) in a first zone (6) of a reaction chamber (3); - a second catalyst bed (7) in a second zone (8) of the reaction chamber, wherein the second zone is located downstream of the first zone in the flow direction of the ammonia feedstock stream; the first and second catalyst beds are configured to carry out an endothermic decomposition reaction of ammonia into the reaction chamber (3); and the first catalyst bed has an activation temperature lower than that of the second catalyst bed.

Description

Technical Field

[0001] The field of the present invention is the field of reactors for producing a synthesis gas product comprising hydrogen from an ammonia feed stream process for producing a synthesis gas product. The present invention also relates particularly to a process for producing a synthesis gas product comprising hydrogen. The present invention also relates to the use of such a reactor for ammonia decomposition. The present invention also relates to a furnace comprising such a reactor.

Background Art

[0002] The production of a synthesis gas product comprising hydrogen by the endothermic decomposition reaction of an ammonia feed stream can be carried out in a catalytic reactor at a high temperature, generally between 400°C and 800°C. Such units typically comprise a metal shell, a catalyst, and an external heat source. In order to achieve the lowest possible CO2 footprint for the decomposition process, the external heat source is provided only by the combustion of an ammonia fuel stream in a furnace. This process requires a large amount of heat and energy.

[0003] Today, it is not possible to have a uniform temperature along the entire reactor of an endothermic reaction. The catalyst in the reactor unit has specific characteristics such as a specific activation temperature and stability characteristics. Therefore, the catalyst does not have the same activity along the entire reactor, and the conversion rate is not optimized.

[0004] The present invention proposes a reactor in which the conversion rate is optimized according to the temperature profile along the entire reactor.

Summary of the Invention

[0005] For this purpose, the present invention is a reactor for producing a synthesis gas product comprising hydrogen from an ammonia feed stream, the reactor comprising - an external shell tube comprising a reaction chamber, - an intake for the ammonia feed stream, where the intake is fluidly connected to the reactor, - An exhaust port for synthesis gas products containing hydrogen, where the exhaust port is configured to release synthesis gas products from the reactor. - The first catalyst bed in the first zone of the reaction chamber, - The second catalyst bed in the second zone of the reaction chamber, where the second zone is located downstream of the first zone in the flow direction of the ammonia feedstock stream, We propose a reactor comprising a first and a second catalyst bed configured to carry out an endothermic decomposition reaction of ammonia into the reaction chamber, wherein the first catalyst bed has an activation temperature lower than that of the second catalyst bed.

[0006] The reactor of the present invention makes it possible to optimize the decomposition reaction along the entire reaction chamber and limit the degradation of the catalyst beds, which have their own activation temperatures.

[0007] According to one aspect of the present invention, the first zone is adjacent to the second zone.

[0008] According to one aspect of the present invention, the first zone and the second zone are separated by a fluid permeable layer disposed to hold the first catalyst bed in the first zone and the second catalyst bed in the second zone. In a modified embodiment, the catalysts of the first and second catalyst beds may be stacked and packed together.

[0009] According to one aspect of the present invention, the activation temperature of the first catalyst bed is set to 200°C to 400°C.

[0010] According to one aspect of the present invention, the activation temperature of the second catalyst bed is set to 300°C to 500°C.

[0011] The temperature at the ammonia feedstock stream intake is lower than the temperature at the synthesis gas product exhaust. In fact, the reactor temperature increases along the entire tube. As a result, the activation temperature of the first catalyst bed is lower than that of the second catalyst bed, the decomposition reaction is optimized, and the catalyst bed is not damaged by the excessively high temperatures of the ammonia feedstock stream and / or the partially decomposed synthesis gas stream.

[0012] According to one aspect of the present invention, the catalyst bed comprises a catalytically active material, particularly a support, such as an aluminum oxide (Al2O3) support, on which the catalytically active material is located. Such a material is capable of avoiding nitridation.

[0013] According to one aspect of the present invention, the first and second catalyst beds comprise the same catalytically active material, for example, nickel as the catalytically active material.

[0014] According to one aspect of the present invention, the first and second catalyst beds comprise the same catalytically active material, for example, nickel, at different concentrations. For example, the first catalyst bed comprises 10 to 50% by weight of nickel, preferably 20 to 40% by weight of nickel, as the catalytically active material, and the second catalyst bed comprises 10 to 45% by weight of nickel, preferably 15 to 30% by weight of nickel, as the catalytically active material.

[0015] According to one aspect of the present invention, the first catalyst bed comprises a catalytically active material different from the catalytically active material of the second catalyst bed. For example, the first catalyst bed comprises ruthenium as the catalytically active material, and the second catalyst bed comprises nickel as the catalytically active material.

[0016] According to one aspect of the present invention, the first catalyst bed comprises 0.5 to 4% by weight of ruthenium as a catalytically active material.

[0017] According to one aspect of the present invention, the catalyst bed is a structured catalyst layer.

[0018] According to one aspect of the present invention, the catalyst bed is a randomly packed catalyst bed (dumped catalyst beds).

[0019] According to one aspect of the present invention, the reactor comprises more than two catalyst beds, each catalyst bed located in a different zone of the reaction chamber.

[0020] According to one aspect of the present invention, the catalyst bed provided in the zone closest to the ammonia feed stream inlet has the lowest activation temperature among all the catalyst beds, and the catalyst bed provided in the zone closest to the syngas product outlet has the highest activation temperature among all the catalyst beds.

[0021] According to one aspect of the present invention, the catalyst beds are configured such that their activation temperatures increase from the inlet towards the outlet, and each catalyst bed has its activation temperature.

[0022] According to one aspect of the present invention, the second catalyst bed is configured such that the ammonia feed stream flowing through the second catalyst bed has a higher temperature than the ammonia feed stream circulating through the first catalyst bed.

[0023] According to one aspect of the present invention, the reactor is configured to be heated by an external heat source.

[0024] According to one aspect of the present invention, the second catalyst bed is configured to be heated by the external heat source such that the ammonia feed stream flowing through the second catalyst bed is heated, and the first catalyst bed is configured such that the ammonia feed stream flowing through the first catalyst bed has a lower temperature than in the second catalyst bed. Thus, the second catalyst bed will safely start before approaching the maximum applicable temperature of the first catalyst bed. The maximum applicable temperature of the catalyst bed here means the maximum temperature to which the catalyst bed can be exposed. Exceeding such a maximum applicable temperature can damage the catalyst.

[0025] According to one aspect of the present invention, the reactor is configured such that the syngas product at the reactor outlet has a temperature consisting of 600 °C to 800 °C.

[0026] According to one aspect of the present invention, the reactor is configured such that the ammonia feed stream at the reactor inlet has a temperature consisting of 150 °C to 650 °C.

[0027] According to one aspect of the present invention, the reactor comprises a protective layer, the protective layer is configured to retain impurities from the ammonia feed stream, and the protective layer is disposed upstream of the first zone of the reaction chamber in the flow direction of the ammonia feed stream.

[0028] According to one aspect of the present invention, the protective layer comprises at least one material configured to retain impurities (such as impurities like chlorine, chloride, iron, chromium, oil, or salts) from the ammonia feed stream, and the material is selected from, for example, copper or nickel or a material having a specific surface area.

[0029] According to one aspect of the present invention, the protective layer comprises 20 to 45 wt% nickel.

[0030] According to one aspect of the present invention, the reactor has a length extending along the entire reactor.

[0031] According to one aspect of the present invention, the length of the reactor is defined by two end portions and a longitudinal wall defining the range of the internal volume of the reactor. In one aspect of the present invention, the longitudinal wall is a cylindrical wall extending between the two end portions.

[0032] According to one aspect of the present invention, the protective layer has a length within the range of 0 to 20%, preferably 5 to 20% of the length of the reaction chamber.

[0033] According to one aspect of the present invention, the reactor comprises a heat exchanger configured to be in a heat exchange relationship with the reaction chamber.

[0034] According to one aspect of the present invention, a heat exchanger is located inside the reaction chamber, and the reactor is configured to pass an ammonia raw material stream through a catalyst bed located in a first zone and a catalyst bed located in a second zone after the ammonia raw material stream enters the reaction chamber, thereby catalytically converting the ammonia raw material stream into synthesis gas products in the catalyst beds, and passing the synthesis gas products through a heat exchanger, the heat exchanger being located inside the reaction chamber so as to be in a heat exchange relationship with the catalyst beds and the ammonia raw material stream. In other words, the reactor comprises a set of volumes for circulating the ammonia raw material stream and the partially decomposed synthesis gas stream through the catalyst beds and for passing the synthesis gas products through a heat exchanger.

[0035] In one aspect of the present invention, the reactor is configured to circulate an ammonia feedstock stream through a catalyst bed and to flow synthesis gas products through a heat exchanger in a countercurrent to the circulation through the catalyst bed.

[0036] According to one aspect of the present invention, the heat exchanger comprises at least one synthesis gas product circulation duct, the duct being arranged for heat exchange between the discharged synthesis gas product and the catalyst bed.

[0037] According to one aspect of the present invention, the synthesis gas product circulation duct is made of stainless steel comprising nickel, such as alloy 600, alloy 625, stainless steel SS310, nickel-coated steel, or aluminum-plated steel. Such materials can promote the conversion of ammonia to hydrogen and nitrogen while avoiding nitriding.

[0038] According to one aspect of the present invention, the walls of the shell tube are configured to be protected from nitriding. Protection from nitriding can be implemented throughout the entire thickness of the wall or only on a portion of the wall thickness.

[0039] According to one aspect of the present invention, the shell walls are centrifugal cast.

[0040] According to one aspect of the present invention, the wall of the shell tube is a microalloy wall.

[0041] According to one aspect of the present invention, the walls of the shell tube are made of a material configured to be protected from nitriding, and the inner walls of the shell tube are optionally aluminum-plated or coated by build-up welding.

[0042] According to one aspect of the present invention, the walls of the shell tube do not have a corrosion-resistant layer. In this invention, there is no problem of metal dusting that leads to corrosion.

[0043] According to one aspect of the present invention, the heat exchanger is configured to recover heat from catalyst conversion in the reaction chamber and direct the recovered heat towards the reaction chamber, particularly the catalyst bed.

[0044] According to one aspect of the present invention, the heat exchanger is a heat exchange coil.

[0045] According to one aspect of the present invention, the heat exchange coil includes a synthesis gas product circulation duct.

[0046] According to one aspect of the present invention, the heat exchanger comprises two synthesis gas product circulation ducts.

[0047] According to one aspect of the present invention, the heat exchanger comprises two heat exchange coils, the heat exchange coils being intertwined. The heat exchange coils may be helical or partially linear and helical.

[0048] According to one aspect of the present invention, the heat exchanger is provided with an inlet configured to supply synthesis gas products to the synthesis gas product circulation duct after catalytic conversion of the ammonia raw material stream in the catalyst bed.

[0049] According to one aspect of the present invention, the heat exchanger is provided with an outlet configured to discharge synthesis gas products from the heat exchanger.

[0050] According to one aspect of the present invention, the reaction chamber is a part of a reactor arranged for a decomposition reaction.

[0051] According to one aspect of the present invention, the reaction chamber comprises all zones that include a catalyst bed.

[0052] According to one aspect of the present invention, the reaction chamber has a total length that extends along the entire zone comprising the catalyst bed.

[0053] According to one aspect of the present invention, the first zone has a length in the range of 10% to 50%, preferably 20% to 40%, of the total length of the reaction chamber. The first zone may begin from the starting end of the reaction chamber. In a modified form, the first zone may begin at a point away from the starting end of the reaction chamber. For example, the starting point of the first zone may be located in the first 20% of the length of the reaction chamber. The first zone may end in the region of the reaction chamber that is in the first 20% to 50% of the length of the reaction chamber.

[0054] According to one aspect of the present invention, the second zone has a length in the range of 90% to 50%, preferably 80% to 60%, of the total length of the reaction chamber. The second zone may begin in the first 20% to 50% of the reaction chamber's total length. The second zone may end at the terminal end of the reaction chamber.

[0055] The present invention also relates to a furnace for decomposing ammonia, comprising at least one reactor as disclosed above and at least one heating device for heating the reactor.

[0056] According to one aspect of the present invention, the furnace comprises a plurality of reactors and / or a plurality of heating devices, as previously disclosed.

[0057] According to one aspect of the present invention, the heating device comprises a combustion chamber configured to heat a reactor by a combustion reaction of a fuel gas.

[0058] According to one aspect of the present invention, the reactor is located in the combustion chamber.

[0059] According to one aspect of the present invention, the combustion chamber is defined by at least one wall, the wall being particularly insulating.

[0060] According to one aspect of the present invention, the combustion chamber is defined by an upper wall, a lower wall, and at least one longitudinal wall, for example, a cylindrical wall, wherein the wall is particularly insulating. In another example, the at least one longitudinal wall comprises four transverse walls. In particular, the combustion chamber has a box shape.

[0061] According to one aspect of the present invention, the length of the reaction chamber of the reactor is measured from the upper wall of the combustion chamber to the lower wall of the combustion chamber.

[0062] According to one aspect of the present invention, the combustion chamber comprises at least one burner configured to burn a fuel gas stream in the combustion chamber to supply heat to a reactor.

[0063] According to one aspect of the present invention, at least one burner is located on the ammonia raw material stream intake side of the reactor.

[0064] According to one aspect of the present invention, the reactors are arranged fluidly parallel to each other.

[0065] According to one aspect of the present invention, the burner is positioned on the upper wall of the combustion chamber.

[0066] According to one aspect of the present invention, the burner is positioned on the lower wall of the combustion chamber.

[0067] The present invention also relates to a process for producing a synthesis gas product comprising hydrogen by an endothermic decomposition reaction of an ammonia feedstock stream, - A step of supplying an ammonia raw material stream through an air intake to a reactor equipped with a reaction chamber, -A step of carrying out a first endothermic reaction of an ammonia feedstock stream at a first temperature within a first temperature range in a first zone of the reaction chamber, thereby obtaining a partially decomposed synthesis gas stream, -A step of carrying out a second endothermic reaction of the ammonia feedstock stream at a second temperature within a second temperature range in a second zone of a reaction chamber downstream of the first zone, in the flow direction of the ammonia feedstock stream and the partially decomposed synthesis gas stream, thereby obtaining a decomposed synthesis gas stream having optionally unconverted ammonia, -Here, the second temperature is higher than the first temperature. - A step of discharging the synthesis gas products obtained in the first and second endothermic reactions through an exhaust port. Regarding processes that include [specific features / features].

[0068] According to one aspect of the present invention, a first endothermic reaction is carried out on a first catalyst bed, and a second endothermic reaction is carried out on a second catalyst bed different from the first catalyst bed.

[0069] The synthesis gas product comprises hydrogen and nitrogen, and optionally unconverted ammonia.

[0070] According to one aspect of the present invention, the process comprises the step of heating the reaction chamber with external heat.

[0071] According to one aspect of the present invention, the ammonia raw material stream is heated by the external heat in the first and second catalyst beds to carry out the first and second endothermic reactions.

[0072] According to one aspect of the present invention, the ammonia feedstock stream and / or partially decomposed synthesis gas stream circulates in the first catalyst bed at a lower temperature than in the second catalyst bed. Therefore, the second catalyst bed will start safely before approaching the maximum operating temperature of the first catalyst bed.

[0073] According to one aspect of the present invention, the first endothermic reaction is carried out at a temperature ranging from 200°C to 400°C.

[0074] According to one aspect of the present invention, the second endothermic reaction is carried out at a temperature ranging from 300°C to 500°C.

[0075] According to one aspect of the present invention, the ammonia raw material stream enters the reactor through the ammonia raw material stream inlet at a temperature ranging from 150°C to 650°C.

[0076] According to one aspect of the present invention, the decomposed synthesis gas stream is discharged through a synthesis gas product exhaust port at a temperature ranging from 600°C to 800°C.

[0077] The present invention also relates to the use of previously disclosed reactors for endothermally decomposing an ammonia feedstock stream into synthesis gas products.

[0078] Further features, details, and advantages of the present invention will become clearer from reading the description given below with reference to the drawings. [Brief explanation of the drawing]

[0079] [Figure 1] This is a schematic diagram of a reactor according to the first embodiment of the present invention. [Figure 2] This is a schematic diagram of a reactor according to a second embodiment of the present invention. [Figure 3] This is a schematic diagram of a reactor according to a third embodiment of the present invention. [Figure 4] This is a schematic diagram of a reactor according to a fourth embodiment of the present invention. [Figure 5] Figure 1 is a schematic diagram of a furnace equipped with a reactor. [Figure 6] This is a schematic diagram of a furnace according to another embodiment, equipped with the reactor shown in Figure 1. [Modes for carrying out the invention]

[0080] Figure 1 is a schematic diagram of a reactor for producing synthesis gas containing hydrogen from an ammonia feedstock stream according to the first embodiment.

[0081] In this embodiment, the reactor 1, with a total length L, includes an external shell tube 2, which is pressurized. The external shell tube 2 contains a reaction chamber 3 in which catalytic conversion of the ammonia raw material stream is carried out, and this catalytic conversion is a decomposition reaction.

[0082] The outer shell tube 2 is equipped with an ammonia raw material stream tube inlet 4, and the tube inlet 4 is configured to allow the fluid to flow into the outer shell tube 2, or more precisely, into the reaction chamber 3.

[0083] Reaction chamber 3 comprises two catalyst beds, namely a first catalyst bed 5 in the first zone 6 of reaction chamber 3, and a second catalyst bed 7 located in the second zone 8 of reaction chamber 3. The first zone 6 is located upstream of the second zone 8 in reaction chamber 3 in the flow direction of the ammonia feedstock stream.

[0084] The reactor 1 is equipped with an exhaust port 9 for the synthesis gas product containing hydrogen, and the exhaust port 9 is configured to release the synthesis gas product from the reactor 1 after the ammonia raw material stream has been decomposed into the synthesis gas product.

[0085] Reactor 1 is configured such that an ammonia feedstock stream enters the reactor 1 through an intake port 4, flows through a first catalyst bed 5 in a first zone 6, and flows through a second catalyst bed 7 in a second zone 8. In the first and second catalyst beds 5 and 7, the ammonia feedstock stream is decomposed into synthesis gas products containing hydrogen. The reactor 1 is then configured such that the synthesis gas products exit the reactor 1 through an exhaust port configured to release the synthesis gas products. Synthesis gas is the product of the endothermic decomposition reaction of ammonia. Therefore, "synthesis gas products" means the decomposed gas products containing hydrogen and nitrogen.

[0086] The first catalyst bed 5 is closer to the ammonia feedstock stream inlet 4 than the second catalyst bed 7. The first catalyst bed 5 has a lower activation temperature than the second catalyst bed 7. Both the first catalyst bed 5 and the second catalyst bed 7 comprise a catalytically active material, particularly a support, such as an aluminum oxide (Al2O3) support. Such materials can avoid nitridation. The first catalyst bed 5 is configured to carry out the decomposition reaction of the ammonia feedstock stream at a lower temperature than the second catalyst bed 7, thereby obtaining a partially decomposed synthesis gas stream. The first catalyst bed 5 comprises, for example, 10 to 50 wt% nickel, preferably 20 to 40 wt% nickel, or 0.5 to 4 wt% ruthenium as the catalytically active material. The second catalyst bed 7 comprises, for example, 10 to 45 wt% nickel, preferably 15 to 30 wt% nickel as the catalytically active material. A second endothermic reaction in the ammonia feedstock stream occurs downstream of the first zone in the flow direction of the ammonia feedstock stream and the partially decomposed synthesis gas stream, thereby obtaining a decomposed synthesis gas stream containing optionally unconverted ammonia.

[0087] The first catalyst bed 5 is configured to carry out the decomposition reaction at a temperature ranging from 200°C to 400°C, and the second catalyst bed 7 is configured to carry out the decomposition reaction at a temperature ranging from 300°C to 500°C.

[0088] In other words, the first catalyst bed 5 may have the same catalytically active material as the second catalyst bed 7, but may have different concentrations of the catalytically active material, or the first catalyst bed 5 may have a different catalytically active material than the second catalyst bed 7.

[0089] The reactor is configured such that the temperature of the ammonia raw material stream at the intake port ranges from 150°C to 650°C, and the decomposed synthesis gas stream is discharged at a temperature of 600°C to 800°C through the synthesis gas product exhaust port.

[0090] The first catalyst bed 5 and the second catalyst bed 7 are, for example, two structured catalyst layers or two randomly packed catalyst beds.

[0091] The reaction chamber 3 has a length l that extends along the entirety of the first and second zones, which are provided with the first and second catalyst beds. The first zone has a length in the range of 10% to 50% of the length l of the reaction chamber, and the second zone has a length in the range of 90% to 50% of the length l of the reaction chamber.

[0092] Figure 2 is a schematic diagram of a reactor for producing synthesis gas containing hydrogen from an ammonia feedstock stream, according to a second embodiment.

[0093] In this embodiment, the reactor 101 comprises three catalyst beds 105, 107, and 109 located in the reaction chamber 103.

[0094] The first catalyst bed 105 is located in the first zone 106, which is upstream of the second catalyst bed 107, and the second catalyst bed 107 is located in the second zone 108, which is upstream of the third catalyst bed 109, which is located in the third zone 110 of the reaction chamber 103.

[0095] The first catalyst bed 105 is closest to the ammonia raw material stream intake port 102 and has the lowest activation temperature. The third catalyst bed 109 is closest to the synthesis gas product exhaust port 111 and has the highest activation temperature. The second catalyst bed 107 is located between the first catalyst bed 105 and the third catalyst bed 109 and has an activation temperature that is between the activation temperature of the first catalyst bed 105 and the activation temperature of the third catalyst bed 109.

[0096] In other embodiments not shown herein, the reactor 101 comprises more than three catalyst beds. The catalyst beds have different activation temperatures and comprise either different catalytic materials or the same catalytic material at different concentrations.

[0097] Other features of the second embodiment are the same as those of the first embodiment.

[0098] Figure 3 is a schematic diagram of a reactor for producing synthesis gas containing hydrogen from an ammonia feedstock stream, according to the third embodiment.

[0099] The features of the first embodiment are the same as those of the third embodiment. In the third embodiment, in addition to the features of the first embodiment, the reactor 201 includes a protective layer 209 located upstream of the reaction chamber 203, more precisely upstream of the first catalyst bed 205. This protective layer 209 is fluidly connected to the ammonia feedstock stream inlet 202 and is configured to retain impurities from the ammonia feedstock stream before the ammonia feedstock stream flows through the first catalyst bed 205 and the second catalyst bed 207.

[0100] Figure 4 is a schematic diagram of a reactor for producing synthesis gas containing hydrogen from an ammonia feedstock stream, according to the fourth embodiment.

[0101] The features of this embodiment are the same as those of the first embodiment.

[0102] In addition to the features of the first embodiment, the outer shell tube 302, more precisely the reaction chamber 303, here comprises a heat exchanger 310, which is located inside the reaction chamber 303 so as to be in heat exchange relationship with the catalyst beds 305 and 307 and the ammonia raw material stream. In this embodiment, the heat exchanger 310 comprises two heat exchange coils 312 and 313, which are intertwined.

[0103] The catalyst beds 305 and 307 are configured to be partially heated by external heat from an external heat source. The external heat source is, for example, external combustion or electric heating. The ammonia raw material stream is thus converted into a gas synthesis product containing hydrogen. The ammonia raw material is heated, and the heat is supplied to the decomposition reaction. The already decomposed gas is then further heated. As the high-temperature gas synthesis product flows through the synthesis gas product circulation duct of the heat exchanger 310, the high-temperature gas synthesis product internally transfers its heat to the catalyst beds 305 and 307. Thus, the catalyst beds are heated by the external heat source and the internal heat source. This reduces the consumption of external heat. Here, the synthesis gas product flows through the heat exchanger 310 in a countercurrent manner to the ammonia raw material stream and the partially decomposed synthesis gas stream passing through the catalyst beds.

[0104] The synthesis gas product circulation duct is made of a thermally conductive material such as a metal alloy, for example, alloy 600. In another embodiment not shown herein, the heat exchanger comprises one or at least two tubes made of the thermally conductive material.

[0105] Reactor 301 is configured to allow an ammonia feedstock stream to enter the reaction chamber 303 through an inlet, then to flow through a first catalyst bed 305 and then through a second catalyst bed 307, causing at least a portion of the feedstock stream to decompose into synthesis gas products in the catalyst beds 305 and 307, and to flow the synthesis gas products through a circulation duct provided in a heat exchanger 310, which is located inside the reaction chamber 303.

[0106] The heat exchanger includes an outlet 315 configured to discharge synthesis gas products from the heat exchanger.

[0107] The reactors of the second and third embodiments may also be combined with heat exchangers such as those disclosed herein.

[0108] Figures 5 and 6 are schematic diagrams of a furnace for decomposing ammonia, comprising a plurality of reactors 1 as disclosed in Figure 1 in a combustion chamber 403. The furnace 400 comprises a plurality of burners 402 configured to generate flames and heat the reactors 1. In this embodiment, the reactors 1 are fluidly arranged parallel to each other.

[0109] The furnace comprises an upper wall, a lower wall, and longitudinal walls, the walls being insulated. These walls are arranged to define the extent of the furnace. At least one longitudinal wall comprises four transverse walls, and the combustion chamber has a box shape.

[0110] In the embodiment shown in Figure 5, the burner and reactor air intake are located on the upper wall. In the embodiment shown in Figure 6, the burner and reactor air intake are located on the lower wall.

[0111] The reactors shown in Figures 5 and 6 may be reactors 101, 201, and 301 of the second, third, and fourth embodiments of the present invention.

Claims

1. A reactor (1) for producing a synthesis gas product containing hydrogen from an ammonia raw material stream, wherein the reactor is - External shell tube (2) equipped with reaction chamber (3), - Intake port (4) for the ammonia raw material stream, where the intake port is fluidly connected to the reactor, - Exhaust port (9) for the synthesis gas product containing hydrogen, wherein the exhaust port is configured to release the synthesis gas product from the reactor, - The first catalyst bed (5) in the first zone (6) of the reaction chamber (3), - A second catalyst bed (7) in the second zone (8) of the reaction chamber, where the second zone is located downstream of the first zone in the flow direction of the ammonia raw material stream, A reactor comprising, wherein the first and second catalyst beds are configured to carry out the endothermic decomposition reaction of ammonia into the reaction chamber (3), and the first catalyst bed has an activation temperature lower than that of the second catalyst bed.

2. The reactor according to claim 1, wherein the activation temperature of the first catalyst bed (5) is 200°C to 400°C.

3. The reactor according to claim 1 or 2, wherein the activation temperature of the second catalyst bed (7) is 300°C to 500°C.

4. The reactor according to any one of claims 1 to 3, wherein the first and second catalyst beds are each comprised of the same catalytically active material at different concentrations, for example, a catalytically active material comprising nickel.

5. The reactor according to any one of claims 1 to 3, wherein the first catalyst bed (5) comprises a catalytically active material different from the catalytically active material of the second catalyst bed (7).

6. The reactor according to any one of claims 1 to 5, comprising more than two catalyst beds, each catalyst bed located in a different zone of the reaction chamber, the catalyst beds configured such that their activation temperature increases from the intake port to the exhaust port, and each catalyst bed having its activation temperature.

7. The reactor according to any one of claims 1 to 6, wherein the wall of the outer shell tube (2) is configured to be protected from nitriding.

8. The reactor according to any one of claims 1 to 7, wherein the reaction chamber (3) has a total length that extends along the entirety of the zone comprising the catalyst bed, and the first zone has a length in the range of 10% to 50%, preferably 20% to 40%, of the total length of the reaction chamber.

9. The reactor according to any one of claims 1 to 8, wherein the reaction chamber (3) has a total length that extends along the entirety of the zone comprising the catalyst bed, and the second zone has a length in the range of 90% to 50%, preferably 80% to 60%, of the total length of the reaction chamber.

10. A process for producing synthesis gas products containing hydrogen by the endothermic decomposition reaction of an ammonia raw material stream, - A step of supplying the ammonia raw material stream through an air intake (4) into a reactor (1) equipped with a reaction chamber (3), - A step of carrying out a first endothermic reaction of the ammonia feedstock stream at a first temperature within a first temperature range in a first zone (6) of the reaction chamber, thereby obtaining a partially decomposed synthesis gas stream, - A step of carrying out a second endothermic reaction of the ammonia feedstock stream at a second temperature within a second temperature range in a second zone (8) of the reaction chamber downstream of the first zone, in the flow direction of the ammonia feedstock stream and the partially decomposed synthesis gas stream, thereby obtaining a decomposed synthesis gas stream containing optionally unconverted ammonia, -Here, the second temperature is higher than the first temperature, - A step of discharging the synthesis gas products obtained in the first and second endothermic reactions through the exhaust port. A process that includes [the following].

11. The process according to claim 10, wherein the first endothermic reaction is carried out on a first catalyst bed, and the second endothermic reaction is carried out on a second catalyst bed different from the first catalyst bed.

12. The process according to claim 10 or 11, wherein the first endothermic reaction is carried out at a temperature of 200°C to 400°C.

13. The process according to any one of claims 10 to 12, wherein the second endothermic reaction is carried out at a temperature of 300°C to 500°C.

14. Use of the reactor according to any one of claims 1 to 9 for endothermally decomposing an ammonia raw material stream into synthesis gas products.

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