Ammonia cracking system and process

Abstract

The present disclosure provides processes and systems for hydrogen production as well as transport of hydrogen. The systems and processes for hydrogen production can include reacting a hydrogen source compound, such as ammonia, so that it decomposes into hydrogen and any remaining components. The reaction products can then be separated to isolate substantially pure hydrogen. Heating for the reaction can be provided via a combustion product stream comprising predominantly carbon dioxide. Beneficially, hydrogen can be moved from a first location of availability to a second location of non-availability by carrying out reactions for converting the hydrogen at the first location into an intermediate compound (for example, ammonia), transporting the ammonia to the second location, and then decomposing the intermediate compound to provide the hydrogen.

Description

AMMONIA CRACKING SYSTEM AND PROCESSCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and the benefit of U.S. provisional patent application serial No. 63 / 605,233, filed December 1, 2023, and entitled “AMMONIA CRACKING SYSTEM AND PROCESS,” the entire contents of which are incorporated by reference for all purposes.BACKGROUND

[0002] Hydrogen has been proposed for many years as a clean energy source capable of world-wide use. There are several conventional methods for producing hydrogen. For instance, hydrogen can be produced by electrolysis of water in pressurized electrolysis plants, but the power consumption of such processes is very high, and the electricity source must be carbon free to secure an environmental advantage. As another example, hydrogen can also be produced by steam methane reforming or gasification of hydrocarbons, such as coal, natural gas, or methane, and such processes can be particularly useful if carried out in a manner that achieves capture of any produced carbon products.

[0003] Future use of hydrogen as a world-wide energy source can depend in part on the availability of low- cost reliable sources of fossil fuels for hydrogen production. All uses of fossil fuels will be possible only if most or all of the carbon in the fuel is produced in a suitable form for sequestration (for example, as high- pressure, substantially pure carbon dioxide (CO2) gas or liquid). Another limiting factor is the ability to transport hydrogen from areas where fossil fuels are relatively cheap, such as North America and the Middle East, to areas with high population densities, such as Europe and Asia, where suitable fossil fuels, such as natural gas and light hydrocarbon fuels, for hydrogen production are relatively expensive.BRIEF SUMMARY

[0004] The present disclosure provides for the isolation of hydrogen from a hydrogen source compound, such as ammonia. For instance, one or more embodiments include systems and processes for converting, such as cracking, ammonia into its individual components, specifically hydrogen and nitrogen. In addition, one or more embodiments of the present disclosure may also allow for the capture of substantially all of any carbon dioxide that is produced.

[0005] For instance, in one or more embodiments, the present disclosure provides systems and processes for hydrogen production from a hydrogen source compound, such as ammonia. Said systems and processes particularly can achieve significantly high efficiency for hydrogen recovery. For example, said systems and processes can achieve efficiencies for hydrogen recovery that exceed 80% molar, such as 85% molar, such as 90% molar, or such as 95% molar based on the total number of moles of hydrogen in the hydrogen source compound being converted. Moreover, said systems and processes can achieve high efficiency for carbon capture. For example, said systems and processes can achieve efficiencies for carbon capture that exceed 90% molar, such as 95% molar, or such as 99% molar based on the total number of moles of carbon in the fossilfuel that is used as a heating source for the hydrogen production process. In particular, the carbon can be captured as a high-pressure, substantially pure CO2 stream for sequestration or other use.

[0006] In one or more embodiments, the present disclosure provides processes for hydrogen production. As a non-limiting example, a hydrogen production process can comprise: providing a stream of a hydrogen source compound into a reactor under conditions so that the hydrogen source compound interacts with a catalyst present in the reactor, the hydrogen source compound being non-carbonaceous; forming a heating fluid stream comprising carbon dioxide and water by passing a stream comprising predominately carbon dioxide through a combustor where a carbonaceous fuel is combusted with an oxidant; providing the heating fluid stream into the reactor under conditions so that the stream of the hydrogen source compound is heated while interacting with the catalyst without intermixing with the heating fluid stream; passing from the reactor a product stream comprising at least hydrogen; and processing the heating fluid stream, after passing from the reactor, so that carbon dioxide in the heating fluid stream is returned to the combustor as part of the stream comprising predominately carbon dioxide or is captured. The process further can comprise various steps for processing the product stream to, for example, isolate a substantially pure stream of hydrogen or remove at least part of any hydrogen source compound remaining in the product stream. In certain embodiments, the hydrogen source compound can comprise ammonia.

[0007] In some embodiments, the present disclosure can provide methods for hydrogen transport. In nonlimiting examples, a method for hydrogen transport can comprise: carrying out a storage reaction whereby hydrogen is reacted with one or more reactants to form an intermediate compound, said reacting being carried out at a first location; transporting the intermediate compound from the first location to a second location that is physically separated from the first location; and at the second location, subjecting the intermediate compound to a decomposition reaction whereby hydrogen is formed and separated as a substantially pure product. In further embodiments, one or both of the storage reaction and the decomposition reaction can be carried out such that heating is provided by combustion of a hydrocarbon fuel. More particularly, substantially all carbon dioxide formed by the combustion of the hydrocarbon fuel can be captured. In further embodiments, the intermediate compound can be ammonia. More particularly, the ammonia can be liquefied before said transporting.

[0008] In some embodiments, the present disclosure can provide hydrogen production plants or systems. In non-limiting examples, a hydrogen production plant can comprise: a reactor configured to receive a stream of a non-carbonaceous hydrogen source compound, the reactor comprising a plurality of tubes at least partially filled with a catalyst effective for decomposition of the non-carbonaceous hydrogen source compound into a product stream comprising at least hydrogen; a combustor configured both to receive a hydrocarbon, an oxidant, and carbon dioxide and to provide a stream comprising carbon dioxide, the combustor being arranged for passage of the stream comprising carbon dioxide to the reactor as a heating fluid; and one or more processing units arranged to receive the heating fluid from the reactor and separate carbon dioxide therefrom for providing at least a portion of the carbon dioxide received by the combustor.

[0009] One or more embodiments are directed to a process for hydrogen production. In an embodiment, the process includes (a) contacting a hydrogen source compound with a catalyst in a reactor, the hydrogen source compound being non-carbonaceous, and (b) combusting a carbonaceous fuel in a combustor in the presence of carbon dioxide to form a heating fluid stream comprising the carbon dioxide and water. In addition, the process includes (c) passing the heating fluid stream into the reactor to heat the hydrogen source compound while the hydrogen source compound is contacting the catalyst without intermixing with the heating fluid stream and the hydrogen source compound. Further, the process includes (d) withdrawing a product stream and the heating fluid stream from the reactor, the product stream comprising at least hydrogen. Still further, the process includes (e) recycling at least some of the carbon dioxide from the heating fluid stream to the combustor after (d).

[0010] One or more embodiments are directed to a hydrogen production plant. In an embodiment, the hydrogen production plant includes a reactor configured to receive a non-carbonaceous hydrogen source compound, the reactor comprising a plurality of tube assemblies at least partially filled with a catalyst effective for decomposition of the non-carbonaceous hydrogen source compound into a product stream comprising at least hydrogen. In addition, the hydrogen production plant includes a combustor configured to receive a hydrocarbon, an oxidant, and carbon dioxide and provide a heating fluid stream comprising carbon dioxide, the combustor being arranged for passage of the heating fluid stream to the reactor as a heating fluid. Further, the hydrogen production plant includes one or more processing units arranged to receive the heating fluid stream from the reactor and to separate carbon dioxide from the heating fluid stream to provide at least a portion of the carbon dioxide received by the combustor.

[0011] One or more embodiments are directed to a method for hydrogen transport. In an embodiment, the method includes (a) carrying out a storage reaction whereby hydrogen is reacted with one or more reactants to form an intermediate compound, said reacting being carried out at a first location. In addition, the method includes (b) transporting the intermediate compound from the first location to a second location that is physically separated from the first location. Further, the method includes (c) subjecting at least some of the intermediate compound to a decomposition reaction whereby hydrogen is formed and separated as a substantially pure product.

[0012] One or more embodiments described comprise a combination of features and characteristics intended to address various shortcomings associated with certain prior devices, systems, and methods. The foregoing has outlined rather broadly the features and technical characteristics of one or more of embodiments in order that the detailed description that follows may be better understood. The various characteristics and features described previously, as well as others, will be readily apparent to those having ordinary skill in the art upon reading the following detailed description, and by referring to the accompanying drawings. It should be appreciated that this disclosure may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes as one or more disclosed embodiments described. It should also be realized that such equivalent constructions do not depart from the spirit and scope of the principles disclosed.BRIEF DESCRIPTION OF THE FIGURES

[0013] For a detailed description of various embodiments, reference will now be made to the accompanying drawings in which:

[0014] FIG. 1 is a flowsheet illustrating a system and process for dissociation of a hydrogen source compound into at least hydrogen according to one or more embodiments disclosed;

[0015] FIG. 2 is an illustration of a system whereby a hydrogen source compound is transported to a hydrogen consumption location from a hydrogen production location according to one or more embodiments disclosed;

[0016] FIG 3 A is a cross-section of a decomposition reactor useful for decomposition of a hydrogen source compound into at least hydrogen according to one or more embodiment disclosed;

[0017] FIG. 3B is a cross-section taken along section A-A in FIG. 3A according to one or more embodiments disclosed;

[0018] FIG. 3C is a cross-section of another decomposition reactor useful for decomposition of a hydrogen source compound into at least hydrogen according to one or more embodiments disclosed;

[0019] FIG. 3D is a cross-section taken along section B-B in FIG. 3C according to one or embodiments disclosed; and

[0020] FIG. 4 is a partial cross-section of the decomposition reactor of FIG. 3C according to one or more embodiments disclosed.DETAILED DESCRIPTION

[0021] The present subject matter will now be described more fully with reference to embodiments thereof. These embodiments are described so that this disclosure will be thorough, complete, and will fully convey the scope of the subject matter to those having ordinary skill in the art. The subject matter can be embodied in many different forms and should not be construed as limited to the embodiments set forth; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. As used in the specification and in the appended claims, the singular forms “a”, “an”, and “the”, include plural referents unless the context clearly dictates otherwise.

[0022] A suitable method for transporting hydrogen over long distances is to convert the hydrogen to ammonia (NH3) and transport the liquid ammonia in tanker ships by sea. However, upon arrival, the ammonia must then be converted back to hydrogen in an efficient, low cost, and clean process.

[0023] The conversion of ammonia to hydrogen (such as H2gas) and nitrogen (such as N2gas) proceeds according to the equation:2NH3= 3H2+ N2where heat is consumed in an amount of around 10.96KcaFgm mol (kilocalories per gram mole). The heat required to crack ammonia can be provided by the combustion of a fossil fuel, such as a hydrocarbon fuel. However, such fossil fuel combustion results in undesirable carbon emissions, defeating the purpose of the ammonia / hydrogen conversion. Thus, there is a need for suitable systems and processes that are capable ofproducing hydrogen from ammonia while also capturing most or all of the carbon produced, such as in the form of carbon dioxide (CO2), for sequestration or other use.

[0024] The present disclosure provides systems and processes for hydrogen production from a hydrogen source compound. In particular, the hydrogen source compound can be processed in a reactor under conditions so that the hydrogen source compound is converted into its constituent components, including at least hydrogen, which can be isolated for use. In certain embodiments, the hydrogen source compound particularly can be a non-carbonaceous material. Ammonia (NH3) in particular can be useful as the hydrogen source compound.

[0025] Processing of the hydrogen source compound can encompass a decomposition reaction or disassociation reaction and may be referenced as cracking. Such reactions are typically endothermic and thus require a source of significant heat that can be continuously provided to the decomposition or disassociation reactor, which may be referred to as a “cracker” or “cracking reactor”. The heat source is preferably carbon friendly and according to embodiments of the present disclosure can be effective to provide the necessary heating while having substantially low or no emissions of CO2 to the atmosphere.

[0026] The present systems and processes further include components useful for forming a heating fluid stream that can be passed into the reactor to provide the necessary heating for the reaction to occur. In some embodiments, the heating fluid stream can comprise carbon dioxide. A carbon dioxide-based heating fluid can be beneficially formed by passing a stream comprising predominately carbon dioxide through a combustor where a carbonaceous fuel is combusted with an oxidant. For example, a CH4fuel gas (or other hydrocarbon fuel) can be combusted using substantially pure oxygen (optionally diluted with carbon dioxide) to produce a combustion product consisting substantially of only CO2 and water. After use in the reactor, the heating fluid can be passed and processed for further use. In particular, water can be condensed and removed in liquid form. Removing water will leave relatively pure CO2, which can be removed as a product stream at any desired pressure for sequestration or other uses. In order to produce a heating fluid delivered at a desirably defined temperature for the decomposition process, the system can include components for recycling at least a portion of the CO2 stream. This recycled CO2 can be introduced into a combustor where it mixes with combustion products to achieve a defined combustor outlet temperature.

[0027] The heating fluid can be passed into a reactor under conditions so that a stream of the hydrogen source compound is heated while intermingling with the catalyst. This can be specifically carried out such that there is no intermixing of the hydrogen source compound stream with the heating fluid stream. In an embodiment, the heating fluid can enter a CO2 gas heated reactor (CHR) where the heating fluid transfers heat to catalyst filled tube assemblies in which the hydrogen source stream (for example, vaporized ammonia) is passing counter-currently and decomposing into H2and other constituents. When ammonia is used as the hydrogen source stream, the other constituents decomposed from the hydrogen source stream in the CHR may include N2. The product stream comprising at least hydrogen and the other constituents, such as N2, as previously described, can pass through an outlet of each of the catalyst filled tube assemblies. In particular, each of the catalyst filled tube assemblies may comprise a plurality of nested tubes, including a central tube coaxially nested within at least one outer tube. The catalyst may be contained in an annulus or annular regiondefined between the central tube and the at least one outer tube, and the outlet of the catalyst filled tube assembly may be defined at an end of the central tube. During operations, the hydrogen source stream may flow in a first axial direction through the catalyst within the annulus, during which at least a portion of the hydrogen source stream may undergo a cracking reaction and form a cracked gas stream comprising hydrogen and other constituent component, such as N2, as previously described. The cracked gas stream then may flow in a second, opposite axial direction through the central tube to the outlet. As a result, the cracked gas stream may transfer heat back into the catalyst contained in the annulus as it flows through the central tube in the second, opposing axial direction.

[0028] Non-limiting examples of suitable catalysts include elemental cobalt, cobalt-containing compounds, and combinations of elemental cobalt and / or cobalt-containing compounds with one or more further metal species. In one or more embodiments, the catalyst can be a cobalt-based material with promoters described in in “Cobalt-based catalysts for ammonia decomposition” by Zofia Lendzion-Bielun, Urszula Narkiewicz, Walerian Arabczyk Materials (Basel), 2013 Jun; 6(6): 2400-2409, the disclosure of which is incorporated by reference.

[0029] The pressure of the heating fluid produced from the combustor can be kept within about 5 bar of the pressure in the decomposition catalyst tubes. In one or more embodiments, the decomposition pressure is in the range about 10 bar to about 100 bar.

[0030] The heating fluid stream leaving the reactor can be processed in one or more steps, after being withdrawn from the CHR, so that carbon dioxide in the heating fluid stream can be returned to the combustor as part of the stream comprising predominantly carbon dioxide or can be captured, such as for sequestration. For example, the heating fluid stream can be cooled to near atmospheric temperature in an economizer heat exchanger followed by a direct water contact heat exchanger. Condensed liquid water can then be removed and the remaining, net CO2product comprising up to 100% of the carbon present in the hydrocarbon fuel can be accounted for and retained. Any remaining CO2from the cooled and dried heating fluid stream can be recycled back to the combustor. For example, the CO2, the CH4, and the oxygen (O2) feeds can all be heated separately yet simultaneously in the economizer heat exchanger before being introduced into the combustor. The O2can be mixed with CO2to give a diluted oxidant stream containing, for example, about 20% to about 30% molar O2concentration, to limit the adiabatic temperature in the combustor and regulate the outlet temperature. In some embodiments, the mixture of CO2and O2can comprise about 15% to about 50% molar O2, such as about 20% to about 40% molar O2.

[0031] In one or more embodiments, the heating fluid inlet temperature to the reactor may be in a range of about 500°C to about 800°C, such as in a range of about 600°C to about 700°C. The heating gas temperature may decline by about 50°C to about 150°C as it passes through the reactor and as its heat is depleted in supporting the reforming reactions.

[0032] The decomposition reaction carried out in the reactor may not go to completion, that is, the decomposition reaction carried out in the reactor may approach but not achieve 100% decomposition of the hydrogen source material into its constituent parts, for example, ammonia into molecular nitrogen and hydrogen. Accordingly, in some embodiments, the outlet product stream from the reactor may comprise upto about 10 % by mass (mass%) or less, such as about 8 mass% or less, or such as about 5 mass% or less, of the hydrogen source compound.

[0033] The outlet product stream (or “product stream”) passing from the reactor can be cooled to near ambient temperature in a heat exchanger which vaporizes and superheats the hydrogen source stream flowing to the reactor. The product stream can be processed to isolate at least the hydrogen component, including steps for removing remaining hydrogen source compound. For instance, when the hydrogen source compound comprises ammonia, the product stream can be passed into a water scrubber column in which a counter-current water stream strips the ammonia from the CO2 vapor and creates an ammonia-water solution. In one or more embodiments, the ammonia-water solution may comprise approximately 35% ammonia by volume. The overhead product from the water scrubber column, comprising 3H2+ N2, then enters a multi-bed pressure swing adsorber (PSA). The PSA produces a substantially pure high-pressure hydrogen product stream and a low-pressure waste gas stream. The waste gas may be compressed up to the combustor pressure and passed to a membrane H2separation unit, which produces a permeate stream and retentate stream. The permeate stream may comprise a substantial portion, such as in a range of from about 50% to about 95%, of the H2from the waste gas stream from the PSA. This permeate stream may be recycled back to the PSA feed stream. The retentate stream from the PSA comprises a minor portion of molecular hydrogen, such as up to about 5%. This retentate stream may be expanded to near atmospheric pressure in a power producing turbine. One of skill in the art may find it is desirable to pre-heat the retentate stream by introducing some fuel, such as additional H2, before heating the retentate stream in a catalytic combustor. The catalytic combustor ensures that the turbine outlet temperature is maintained at a temperature greater than the freezing point of water (0°C or 32°F) after expansion.

[0034] The ammonia-water solution leaving the bottom of the water scrubber tower can be reduced in pressure, such as about 2 bar, and introduced into the base of a second scrubber tower which, in turn, outputs a substantially pure ammonia stream as an overhead product. The substantially pure ammonia stream may comprise at least about 90% molar (mol%) ammonia, such as at least about 95 mol%) ammonia, or such as at least about 97 mol%) ammonia. The substantially pure ammonia stream may be recycled as at least a portion of the hydrogen source stream to the reactor. In order to maintain a water balance around the system, a portion of the ammonia-water solution may be withdrawn and heated to about 100°C in a water recovery unit. The ammonia leaving this unit can be recycled as at least a portion of the hydrogen source stream for the reactor. The water stream output from the water recovery unit, representing excess water generation from the process, may be safely discarded or used elsewhere. The result of this process is that substantially all of the ammonia feed is converted to 3H2+ N2product, and substantially all of the H2is recovered as substantially pure high- pressure hydrogen. In addition, this process also allows substantially all of the carbon in the hydrocarbon fuel used in the process to be recovered as relatively pure CO2at pressures suitable for sequestration or transport.

[0035] An example embodiment of a system 10 and associated process for hydrogen production is illustrated in FIG. 1 and discussed forthcoming. For purposes of illustration to show example values for process parameters, the system 10 and the associated process are described in relation to the use of ammonia as the hydrogen source compound. Use of other hydrogen source compounds would be expected to lead tosimilar values for said parameters. In particular, the system 10 of FIG. 1 is configured to perform a process for decomposing NH3into 3H2+N2at maximum thermal efficiency with substantially all of the CO2produced from the combustion of a fossil fuel being captured. For simplicity the fuel used in the specific example embodiment shown in FIG. 1 is methane CH4(stream 30); however, other carbonaceous fuels are contemplated.

[0036] As shown in FIG. 1, a liquid ammonia (NH3) stream 42 is pressurized in a multistage centrifugal pump 9. In one or more embodiments, the pump 9 may pressurize the liquid ammonia stream 42 to about 45 bar. The discharge stream 40 from the pump 9 may then be heated in heat exchanger 3 to produce a superheated ammonia vapor incoming feed 97. For instance, in one or more embodiments, the superheated ammonia vapor incoming feed 97 have a temperature of about 482°C. The superheated ammonia vapor incoming feed 97 may then pass into a CO2heated reactor (CHR) 15, which will be described in more detail. The CHR 15 may facilitate one or more decomposition reactions that ultimately crack the at least a portion of the ammonia in the superheated ammonia vapor incoming feed 97 into a product stream 79 comprising molecular hydrogen (H2), molecular nitrogen (N2), and residual ammonia. In one or more embodiments, the product stream 79 may comprise about 1 % by weight (wt%) residual ammonia. The product stream 79 passes from the CHR 15 at an elevated temperature, such as about 550°C in one or more embodiment, and is cooled in a heat exchanger 3. In one or more embodiments, the heat exchanger 3 may cool the product stream 79 to about 40°C to form a stream 44. The stream 44 may be further cooled, such as to about 25°C, in one or more embodiments in another heat exchanger 70. The heat exchanger 70 may comprise a water-cooled heat exchanger in one or more embodiments. The outlet stream 62 from the heat exchanger 70 is combined with a hydrogen containing recycle stream 46 to form combined stream 45, which then enters a direct contact scrubber tower 12.

[0037] In the scrubber tower 12, combined stream 45 contacts a downward flowing water stream 61 to produce a bottom product stream 48, which comprises an ammonia-water solution. In one or more embodiments, the ammonia-water solution of the bottom product stream 48 may comprise approximately 30% ammonia. This bottom product stream 48 is reduced in pressure across a valve 71 to form a stream 49. In one or more embodiments, the valve 71 may reduce the pressure of the stream 49 at the outlet to about 2 bar. The stream 49 may combine with an overhead vapor stream 50 from a water recovery unit 14 to form a combined stream 51. Combined stream 51 may then be introduced into an ammonia desorption tower 13. The ammonia desorption tower 13 may pass a bottoms stream 55, where at least a portion of bottoms stream 55 comprises ammonia. For instance, in one or more embodiments, the bottoms stream 55 may comprise about 30% ammonia. This bottoms stream 55 may be bifurcated into a pump inlet stream 56 and a discharge stream 54. The pump inlet stream 56 may pass to a pump 81 that discharges a pressurized stream 57 to a cooler 16 for ammonia desorption tower 13. The cooler 16 may cool the pressurized stream 57 using cooling water (or another cooling fluid) introduced into cooler 16 via entry stream 59 and passing from cooler 16 via exit stream 60. Cooled stream 58 may egress from the cooler 16. The cooled stream 58 has a similar composition as the bottoms stream 55. The cooled stream 58 is introduced into the ammonia desorption tower 13 proximate tothe top, where the introduced material flows generally downward to strip the rising vapor stream of additional ammonia.

[0038] The ammonia desorption tower 13 may produce an overhead product stream 41. In one or more embodiments, ammonia may be a substantial component of the overhead product stream 41, such as having at least about 90 mol%, such as at least 95 mol%, or such as at least about 98 mol%, ammonia. In one or more embodiments, the overhead product stream 41 or at least a portion thereof may be recycled back and combined with the liquid ammonia stream 42 upstream of pump 9.

[0039] The discharge stream 54, which splits off from the bottoms product stream 55, may be heated and then separated in a water recovery unit 14. Specifically, the water recovery unit 14 may separate the discharge stream 54 into a liquid water stream 53 and the overhead vapor stream 50. The reject liquid water stream 53 may comprise substantially pure water, such as comprising less than about 1 mol% ammonia. To accomplish the separation, the water recover unit 14 may heat and strip the stream 54, such as to approximately 120°C, using a hot stripping vapor for heating stream 52, such as a low-pressure steam.

[0040] The overhead product in stream 47 leaving the scrubber tower 12 may enter a multi-bed pressure swing adsorber (PSA) 17 unit. The PSA 17 may, in turn, separate the overhead product stream 47 into a substantially pure H2product stream 72 and a waste gas stream 73. In one or more embodiments, the substantially pure H2product stream 72 may comprise less than 50 ppm (parts per million) of total impurities. The waste gas stream 73 may include at least a portion of the H2 in the overhead product stream 47. For instance, in one or more embodiments, the waste gas stream 73 may comprise up to about 10% of the H2from the overhead product stream 47. The waste stream 73 is compressed in a compressor 18 which may be driven by an electric motor 19 or any other suitable driver. Compressor 18 produces a discharge flow stream 77. For instance, in one or more embodiments, the compressor 18 may receive the waste stream 73 at about 1.1 bar and may discharge the discharge flow stream 77 at about 45 bar. The discharge flow stream 77 may then be introduced into a polymeric membrane gas separation unit 20, which separates the discharge flow stream 77 into a permeate stream 74 and a retentate stream 63. The permeate stream 74 may be rich in hydrogen. For instance, in one or more embodiments, the permeate stream 74 may comprise at least about 75 wt%, such as at least about 80 wt%, or such as at least about 90 wt% of the H2from the waste gas stream 73.

[0041] The permeate stream 74 may then be compressed in compressor 75 which may be driven by electric motor 76 or any other suitable driver. The compressor 75 produces the hydrogen containing recycle stream 46. For instance, in one or more embodiments, the permeate stream 74 may by introduced into the compressor 75 at about 5 bar and the hydrogen containing recycle stream 46 may pass from the compressor 75 at about 42 bar. The compressed stream 46 may then combine with the outlet stream 62 from the heat exchanger 70 to form the combined stream 45 that passes to scrubber tower 12, as previously described.

[0042] The retentate stream 63 passing from the membrane unit 20 may comprise a small amount of H2 from the discharge flow stream 77. For instance, in one or more embodiments, the retentate stream 63 may have a pressure of about 42 bar and may comprise about 3 wt% H2. The retentate stream 63 passes to a catalytic combustion unit 64. Additional H2may be added to the catalytic combustion unit 64 via a stream 67. The catalytic combustion unit 64, utilizing stream 67, may produce a stream 68 that has an elevatedtemperature. For instance, in one or more embodiments, the temperature of the stream 68 may be about 400°C. The stream 68 may be introduced and expanded in a power producing turbine 65 so as to drive an electric generator 66. The expanded stream 68 may be passed from the turbine 65 as a discharge stream 78. In one or more embodiments, the discharge stream 78 may have a temperature of about 40°C.

[0043] A heating fluid stream 115, while is the output from a combustor 1, may be introduced at the top of the CHR 15 to provide heat for the decomposition of ammonia. Specifically, the heating fluid stream 115 may flows downwards and around the outside of a plurality of catalyst filled tube assemblies positioned in the CHR 15 (see FIG. 3A-FIG. 3D and the associated text for details). The heated fluid stream 115 may transfer heat to the catalyst filled tube assembly, forming a cooled stream 116 that then passes from the CHR 15. For instance, in one or more embodiments, the heating fluid stream 115 may enter the CHR 15 at a temperature of about 650°C and a pressure of about 42 bar, where the cooled stream 116 may pass from the CHTR 15 at a temperature of about 550°C.

[0044] Downstream of the CHR 15, the cooled stream 116 may branch into at least two portions, including a first portion 21 and a second portion 22. The first portion 21 is introduced into the heat exchanger 3, where first portion 21 is further cooled to thermally balance the heat exchanger and then egresses as stream 33. In one or more embodiments, the first portion 21 of the cooled stream 116 may be cooled to about 40°C in the heat exchanger 3. The second portion 22 is passed to another heat exchanger 2, where second portion 22 is cooled and egresses as stream 26. In one or more embodiments, the second portion 22 of the cooled stream 116 may also be cooled to about 40°C in the heat exchanger 2.

[0045] The streams 26, 33 may re-combine to produce a re-combined stream 34 that then enters a direct contact water cooler 6. A circulating water stream 80 from the bottom of the direct contact water cooler 6 flows through a pump 8 and passes as a pressurized stream 36. The pressurized stream 36 is then cooled in a heat exchanger 7 by water (or any other cooling fluid), which is introduced into heat exchanger 7 as a first stream 38 and passes as a second stream 39. Pressurized stream 36 may pass from the heat exchanger 7 as a cooled stream 37 that is then passed back to the top of direct contact water cooler 6. A net water product stream 35 leaves the sump of direct contact water cooler 6 under level control. An overhead product stream 32 is emitted from the direct contact water cooler 6. The overhead product stream 32 mostly or substantially comprises CO2. For instance, in one or more embodiments, the overhead product stream 32 may comprise a substantially pure CO2 stream that comprises less than 3 mol%, such as less than 2 mol%, such as less than 1 mol%, such as less than 0.5 mol%, such as less than 0.1 mol%, or such as less than 0.01 mol% impurities.

[0046] The overhead product stream 32 may be pressurized in a compressor 4, which is driven by electric motor 5 or any other suitable driver, to provide compressed stream 31. The compressed stream 31 is apportioned into a net CO2 product stream 28, which is withdrawn under pressure control for sequestration or other uses and a recycle CO2 stream 27. The net CO2 product stream 28 is then heated in heat exchanger 2. In one or more embodiments, the overhead product stream 32 may be at a pressure of about 40 bar and a temperature of about 25°C, and the compressed stream 31 may be at a pressure of about 43 bar.

[0047] A fuel gas stream 30 and an oxidant stream 29 are heated in heat exchanger 2 using the second portion 22 of the cooled stream 116 passed from the CHR 15. In one or more embodiments, the fuel gas stream 30 comprises methane (CH4). In one or more embodiments, the oxidant stream 29 comprises substantially pure oxygen (O2). For instance, the oxidant stream 29 may comprise at least about 98 mol% O2, such as at least about about 99.5 mol% O2. In one or more embodiments, the fuel gas stream 30 may enter the heat exchanger 2 at about 15°C and about 43 bar. In one or more embodiments, the oxidant stream 29 may enter the heat exchanger 2 at about 20°C and about 43 bar. Both the fuel gas stream 30 and oxidant stream 29 may be heated in the heat exchanger 2 simultaneously and separately together and with (separately and simultaneously) the recycle CO2 stream 27.

[0048] The fuel gas stream 29, oxidant stream 29, and recycle stream 27 may pass from the heat exchanger 2 separately as a heated fuel gas stream 23, a heated oxidant stream 24, and a heated CO2 recycle stream 25, respectively. The streams 23, 24, 25 may then be introduced into the combustor 1 to produce the heated outlet stream 115, as previously described. In one or more embodiments, the oxidant stream 29 or the heated oxidant stream 24 may be mixed or combined with the recycle CO2 stream 27 or the heated recycle CO2 stream 25, respectively, upstream of the combustor 1. For instance, in one or more embodiments, the recycle CO2 stream 27 and the oxidant stream 29 are combined upstream of the heat exchanger 2 so that the combined stream comprises about 25 % of the oxidant stream 29 and about 75% of the recycle CO2 stream 27. Without being limited to this or any other theory, such a blend of the recycle CO2 stream 27 and the oxidant stream 29 may provide a reduced adiabatic flame temperature in the combustor 1 similar to that found by combusting fuel in air - the “synthetic air” may have a similar dilution effect.

[0049] In one or more embodiments, the present disclosure also provides methods for transport of hydrogen. In particular, hydrogen can be converted into an intermediate compound, transported from a first location to a second, separate location, and the intermediate compound decomposed at the second location to provide the hydrogen as a substantially pure product. In one or more embodiments, at least some of the intermediate compound may be decomposed during transportation from the first location to the second location for any suitable purpose, such as to produce H2 for use on the transport vehicle or at the second location or another location upon arrival.

[0050] With reference to FIG. 2, a hydrogen transport system 200 is illustrated according to one or more embodiments. The illustrated system particularly can be used for carrying out methods of hydrogen transport. In the example embodiment, ammonia is used as an example intermediate compound, which also may be the same as a hydrogen source compound as otherwise described. As shown in FIG. 2, an ammonia production facility 202 is configured for introducing hydrogen gas 201 and nitrogen gas 203 for reaction to form ammonia. Ammonia production facility 202 also introduces oxygen 211 and a hydrocarbon fuel 205, such as methane (CH4), for combustion to form heat. CO2 209 produced via the combustion of the hydrocarbon fuel may be separated and sequestered or used for other purposes.

[0051] Ammonia production facility 202 may also utilize power, such as electrical power 207, such as to run one or more pumps, compressors, or other components and systems, to facilitate the formation ofammonia. In addition, the ammonia production facility 202 may produce some electrical power 207, such via a turbine or other expander, during operation.

[0052] The ammonia production facility 202 produces an ammonia product (NH3) 210. Such product ammonia 210 may be introduced into one or more transport vehicles 204 for transport from a first location 220 to a second location 206. The first location 220 may be a shipping terminal, port, or other suitable facility that may receive the ammonia product 210 from the ammonia production facility 202 for loading onto the transport vehicle(s) 204. Thus, the first location 220 may be co-located with the ammonia production facility 202 or may be remotely located from the ammonia production facility 202. In one or more embodiments, the first location 220 and the second location 206 may be separated and accessible by a navigable water, such as an ocean, lake, or river. Thus, in one or more embodiments, the transport vehicles 204 may comprise tanker ships; however other modes of transportation are envisioned, such as trucks, rail cars, and flying vehicles, such as planes, helicopters, or dirigibles. In one or more embodiments, the ammonia product 210 may be at least partially transported to the second location 206 via pipeline or fluid conduit; therefore, the use of a transport vehicles 204 is not required. In one or more embodiments, the ammonia product 210 may be produced at the ammonia production facility 202 in a liquid state or converted into a liquid state at the first location 220 prior to transport, such as via transport vehicle 204 or pipeline, as previously described.

[0053] After transport, the ammonia product 210 may be received at a suitable receiving terminal of the second location 206. At the second location 206, the ammonia product 210 may be converted at high efficiency into substantially pure molecular hydrogen 212 utilizing one or more embodiments of the systems and processes, such as by use of one or more embodiments of the system 10 of FIG. 1. Thus, the second location 206 may include an “ammonia decomposition facility.” The ammonia production facility 202 and the ammonia decomposition facility 206 may both use oxy -fuel heating, via the combustion of a hydrocarbon fuel 215 with an oxidant 216, such as oxygen. Oxy -fuel heating for the decomposition reaction may permit the capture of substantially 100% of the carbon in the hydrocarbon fuel used as CO2 213. Capture or conversion into high-pressure CO2 213 may be useful for sequestration or other uses. The ammonia decomposition facility 206 may also use and product electrical power 207 as previously described. Further, the ammonia decomposition facility 206 may produce one or more outlet streams 214 of water, nitrogen gas (N2) or both.

[0054] Details of example embodiments of the CHR reactors 15 for use in one or more embodiments of the system 10 in FIG. 1 are shown in FIG. 3 A, FIG. 3B, FIG. 3C, FIG. 3D, and FIG. 4. For instance, as shown in FIG. 3A, the CHR 15 may define a reaction chamber 150. The reaction chamber 150 may hold a plurality of tube assemblies 152. FIG. 3B shows a cross-section of one of the tube assemblies 152 along section A-A in FIG. 3A.

[0055] Each tube assembly 152 may comprise a plurality of nested tubes or tubulars that are coaxially aligned along an axis 155. For instance, as shown in FIGS. 3A and 3B, each tube assembly 152 may comprises a first or outer tube 153 and a second or inner tube 154 coaxially nested within the outer tube 153 along axis 155 so that an annulus 158 (or annular space) is defined radially between an outer wall of the inner tube 154and an inner wall of the outer tube 153 relative to axis 155. Reaction catalyst 159 may be positioned within the annulus space 158 of each tube assembly 152.

[0056] The inner tube 154 may be referred to as a “product outlet tube” 154, and the outer tube 153 may be referred as a “catalyst tube” 153. During operations, within each tube assembly 152, the ammonia vapor incoming feed 97 comprising the hydrogen source compound (for example, NH3) flows axially upward within the annulus 158 and parallel relative to axis 155 to thereby contact the catalyst 159 and undergo the decomposition reaction and form the product stream 79, as previously described. The top end of the outer tube 153 is capped so that the product stream 79 is forced to pass axially downward and in the opposing direction through the product outlet tube 154 and parallel relative to axis 155.

[0057] The product outlet tube 154 of each tube assembly 152 may be connected to a first tube sheet 151 that at least partially defines a first collection space 160 in the reaction chamber 150. In addition, the catalyst tube 153 of each tube assembly 152 may be connected to a second tube sheet 156 that at least partially defines a second collection space 161 in the reaction chamber 150. The first reaction space 160 may be located vertically below the second collection space 161 in one or more embodiments. The first collection space 160 may receive production that becomes product stream 79 from the inner tubes 154 of tube assemblies 152, and thus may be referred to as an “outlet collection space” 160. Conversely, the second collection space 161 may receive incoming feed via ammonia vapor incoming feed 97 and may distribute the ammonia vapor incoming feed 97 to the catalyst tubes 153 of the tube assemblies 152. Thus, the second collection space 161 may be referred to as a “feed gas distribution space” 161.

[0058] Thus, within the reaction chamber 150, the hydrogen source compound (for example, NH3) feed is introduced as ammonia vapor incoming feed 97 via the feed gas distribution space 161, and the product gas passes as stream 79 via the outlet collection space 160. In addition, the heating fluid 115, which may comprise mostly CO2 and steam, as previously described, circulates within the reaction chamber 150, around the plurality of tube assemblies 152 (particularly around the outer surface of catalyst tubes 153), and leaves as the cooled stream 116, as previously described.

[0059] In one or more embodiments, the heating fluid stream 115 may enter the reaction chamber 150 at or proximate a top end of the CHR 15 and may exit the reaction chamber 150 proximate a bottom end of the CHR 15, such as vertically above the collection spaces 160, 161, as shown in FIG. 3A. The reaction chamber 150 may include one or more structures or features to guide or channel the flow of the heating fluid 115 therethrough to contact with the outer surface of the catalyst tube 154. For instance, as shown in FIG. 3 A, the reaction chamber 150 may include one or more baffles 157 that are configured to promote a serpentine flow of the heating fluid as it progresses generally downward within the reaction chamber 150.

[0060] Referring now to FIGS. 3C and 3D, another example of the CHR 15 is shown according to one or more embodiments. The CHR 15 shown in FIGS. 3C and 3D may be substantially similar to the CHR 15 shown in FIGS. 3A and 3B, and therefore features of the CHR 15 depicted in FIGS. 3C and 3D that are shared with the CHR 15 shown in FIGS. 3 A and 3B are identified with the same reference numerals. The following description will focus on the features of the CHR 15 of FIGS. 3C and 3D that are different from the CHR 15 of FIGS. 3A and 3B. Notably, like the CHR 15 depicted in FIGS. 3A and 3B, the CHR 15 of FIG. 3C includesa plurality of tube assemblies 152, and FIG. 3D shows a cross-sectional view of one of the tube assemblies 152 along section B-B in FIG. 3C.

[0061] As shown in the embodiment of CHR 15 illustrated in FIGS. 3C and 3D, the reaction chamber 150 may include a plurality of additional tubes or sleeves 162 in place of (or possibly in addition to) the baffles 157 (FIG. 3A). Each of the additional tubes 162 may be coaxially positioned about the catalyst tubes 153 of a corresponding one of the tube assemblies 152 to thereby define an outer annulus 163 (or outer annular space) radially between the outer surface of the catalyst tube 153 and the inner surface of the additional tube 162. The additional tubes 162 may be open on a top end and connected to a tube sheet 164 at a lower end. The tube sheet 164 may define a third collection space 165 that is positioned above the first and second collection spaces 160, 161, respectively. During operations, the heating fluid stream 115 may enter the reaction chamber 150 at or proximate the upper end of the CHR 15, and the heating fluid then may flow axially downward through the outer annulus 163 of each tube assembly 152 to transfer heat to the reaction catalyst 159 and fluids flowing in the annulus 158. The then cooled heating fluid stream 115 may exit the outer annulus 163 of the plurality of tube assemblies 152 and enter the third collection space 165 before being passed out of the reaction chamber 150 as the cooled stream 116, as previously described.

[0062] Without being limited to this or any other theory, the additional tubes 162 surrounding the catalyst tube 153 can allow the heating fluid stream 115 to be channeled in a confined annular space to provide a greater heat transfer coefficient and a substantially even gas distribution between each of the tube assemblies 152, resulting in a more consistent heat transfer into and catalytic performance among all the tube assemblies 152.

[0063] In one or more embodiments, the catalyst tubes 153 may include finned outer surfaces to promote heat transfer. For instance, in one or more embodiments, the outer surface of the catalyst tubes 153 may include fins extending normal to the axis 155, forming planar extensions that mn parallel to the axis 155 along at least a portion of the length of the catalyst tube 153. The axially extending fins may facilitate the vertical flow of the heating fluid stream 115 along the outer surface of the catalyst tubes 153 when the additional tubes 162 are included as shown in FIGS. 3C and 3D.

[0064] Referring now to FIG. 4, a more detailed illustration of the fluid flows around and through one of the tube assemblies 152 in the example CHR 15 of FIGS. 3C and 3D is shown according to one or more embodiments. As shown in FIG. 4, for each tube assembly 152, the ammonia vapor incoming feed 97 passes through a porous plug 170 positioned in the annulus 158, proximate the tube sheet 156 and feed gas distribution collection space 161. The porous plug 170 may rest on a locating collar 172 that is also positioned in the annulus 158 below the porous plug 170.

[0065] The top of the catalyst tube 153 is closed with a cap 174 so that product stream 79 flowing axially upward out of the annulus 158 is deflected axially downwards through the outlet tube 154, as previously described. Another porous plug 176 is inserted into the product outlet tube 154 at or proximate to an upper end. The porous plug 176 may rest on a locating collar 178 also located in the product outlet tube 154 below the porous plug 176.

[0066] An extension tube 180 is defined at the top end of the catalyst tube 153. The cap 174 may be engaged with the extension tube 180. The extension tube 180 may be used for filling and emptying catalyst particles. In one or more embodiments, the catalyst 159 is filled up to a point within the extension tube well above the top end of product outlet tube 153. The extension tube is then closed by the cap 174, which in one or more embodiments may comprise a spring-loaded plug that exerts a downward force on the catalyst particles in the product outlet tube 153. Without being limited to this or any other theory, this arrangement prevents bed fluidization and bed movement of the catalyst 159 when flowing gases, such as ammonia vapor incoming feed 97 and product stream 79, upwards through the through the annulus 158 and catalyst 159 contained.

[0067] As is also shown in FIG. 4, a top section of the vessel defining reaction chamber 150 can be removed using a flanged closure 182 to expose the tops of all the tube assembly 152 (particularly the extension tubes 180 of catalyst tubes 153) to facilitate catalyst filling and replacement. Alternatively large manways can be provided above the extension tubes 180 of tube assemblies 152.

[0068] During operations, the heating fluid stream 115, comprising CO2 may enter the reaction chamber 150 through a nozzle (not shown) located in the top head of CHR 15. The heating fluid stream 115 may be at a pressure less than 5 bar difference from the product gas stream 79 leaving the inner tube 154 via the outlet collection space 160. In order to minimize the design temperature of the CHR 15 and to allow low-cost alloys to be used for construction, internal insulation can be used within the reaction chamber 150. The outlet tubes 154 and the surfaces of the tube sheet 151 and any other components which are in contact with gas containing hydrogen at elevated temperature can be fabricated from alloys resistant to hydrogen corrosion.EXPERIMENTAL

[0069] One or more embodiments are further described in relation to one or more specific examples. The prophetic example(s) are provided to illustrate one or more embodiments and should not be limiting to other embodiments.Example

[0070] In one example, the performance of one or more embodiments of an embodiment of the system 10 of FIG. 1 was modeled under specific conditions using computer modeling. In particular, the performance of the modeled plant was calculated based on a plant sized to convert one million metric tons / year of NH3to H2, operating for 8500 hours per year at 100% capacity, where 100% of the NH3is converted to 3H2+N2, and 99% of the H2produced in the NH3decomposition is delivered as pure high pressure H2. The conditions of the ammonia feed (stream 42 in FIG. 1) were set as a saturated liquid at 8 bar. The conditions of hydrogen product stream (stream 72 in FIG. 1) was 40 bar and 25°C. The incoming fuel gas stream (stream 30 in FIG. 1) was selected as methane at 45 bar and 15°C. The conditions of the carbon dioxide separated from the cooled heating fluid in the CHR (stream 31 in FIG. 1) condition was 40 bar, 25°C, and 98% purity (inerts O2+Ar+N2can be removed). Alternatively, separated CO2may be supplied as saturated liquid at 6.5 bar and 99.995% purity. This CO2production captures 100% of the carbon in the methane fuel. The incoming oxidant stream (stream 29 in FIG. 1) may comprise oxygen at 45 bar, 20°C, and 99.5% purity. The modeled plant operatingunder these conditions was found to produce 5MW (Megawatts) of net power. Further details of various parameters of the modeled plant are also shown.Ammonia feed 117.647 metric tons / hrHydrogen production 229777 NnrVhrMethane fuel gas consumption 49494 Nm3 / hrOxygen feed 3425.7 metric tons / dayCarbon Dioxide production 2332.4 metric tons / day

[0071] For the foregoing units of measure, “hr” represents “hour”; “Nm3 / hr” represents “normal meter cubed per hour”, where “normal” means 0 °C and 1 atmosphere pressure (101.325 Kilopascals, or about 1 bar).

[0072] As explained above and reiterated below, the present disclosure includes, without limitation, the following example implementations.

[0073] Clause 1: A process for hydrogen production comprising: (a) contacting a hydrogen source compound with a catalyst in a reactor, the hydrogen source compound being non-carbonaceous; (b) combusting a carbonaceous fuel in a combustor in the presence of carbon dioxide to form a heating fluid stream comprising the carbon dioxide and water; (c) passing the heating fluid stream into the reactor to heat the hydrogen source compound while the hydrogen source compound is contacting the catalyst without intermixing with the heating fluid stream and the hydrogen source compound; (d) withdrawing a product stream and the heating fluid stream from the reactor, the product stream comprising at least hydrogen; and (e) recycling at least some of the carbon dioxide from the heating fluid stream to the combustor after (d).

[0074] Clause 2: The process of any of the clauses, wherein (a) further comprises flowing the hydrogen source compound through one or more tube assemblies positioned in the reactor, and wherein (c) further comprises contacting the heating fluid stream with the one or more tube assemblies within the reactor.

[0075] Clause 3 : The process of any of the clauses, wherein (a) further comprises, for each tube assembly of the one or more tube assemblies, flowing the hydrogen source compound through a first annulus of the tube assembly; and wherein (d) further comprises, for each tube assembly of the one or more tube assemblies, flowing the product stream through an outlet tube of the tube assembly, the outlet tube being coaxially nested within a catalyst tube to define the first annulus between the outlet tube and the catalyst tube.

[0076] Clause 4: The process of any of the clauses, wherein (c) comprises, for each tube assembly of the one or more tube assemblies, flowing the heating fluid stream through a second annulus defined around the catalyst tube.

[0077] Clause 5: The process of any of the clauses, further comprising: (f) splitting the heating fluid stream into a first portion and a second portion after (d); (g) pre-heating the hydrogen source compound with the first portion; and (h) pre-heating the one or more streams flowing to the combustor with the second portion.

[0078] Clause 6: The process of any of the clauses, wherein (h) further comprises preheating an oxidant stream, a fuel gas stream, and the carbon dioxide recycled to the combustor via (e) with the second portion.

[0079] Clause 7: The process of any of the clauses, further comprising: (i) separating a hydrogen product stream from the product stream after (d); (j) separating remaining hydrogen source compound from the productstream after (d); and (k) recycling the remaining hydrogen source compound separated in (j) back to the reactor.

[0080] Clause 8: The process of any of the clauses, wherein the hydrogen source compound comprises ammonia.

[0081] Clause 9: A hydrogen production plant comprising: a reactor configured to receive a non- carbonaceous hydrogen source compound, the reactor comprising a plurality of tube assemblies at least partially filled with a catalyst effective for decomposition of the non-carbonaceous hydrogen source compound into a product stream comprising at least hydrogen; a combustor configured to receive a hydrocarbon, an oxidant, and carbon dioxide and provide a heating fluid stream comprising carbon dioxide, the combustor being arranged for passage of the heating fluid stream to the reactor as a heating fluid; and one or more processing units arranged to receive the heating fluid stream from the reactor and to separate carbon dioxide from the heating fluid stream to provide at least a portion of the carbon dioxide received by the combustor.

[0082] Clause 10: The hydrogen production plant of any of the clauses, wherein each tube assembly of the plurality of tube assemblies comprises: a first tube; a second tube coaxially nested within the first tube along a central axis; and an annulus defined between the first tube and the second tube that is at least a partially filled with the catalyst.

[0083] Clause 11 : The hydrogen production plant of any of the clauses, wherein for each tube assembly of the plurality of tube assemblies, the first tube and second tube are arranged so that: the non-carbonaceous hydrogen source compound is configured to flow in a first axial direction along the central axis within the annulus; and the product stream is configured to flow axially in a second axial direction along the central axis within the second tube, the second axial direction being opposite the first axial direction.

[0084] Clause 12: The hydrogen production plant of any of the clauses, wherein the reactor further comprises: a first tube sheet that is configured to at least partially define a first collection space in the reactor that is in fluid communication with the second tube of each tube assembly of the plurality of tube assemblies; and a second tube sheet that is configmed to at least partially define a second collection space in the reactor that is in fluid communication with the annulus of each tube assembly of the plurality of tube assemblies.

[0085] Clause 13: The hydrogen production plant of any of the clauses, wherein the reactor further comprises one or more baffles that are configured to direct the heating fluid stream in a serpentine flow direction around an outside of the plurality of tube assemblies.

[0086] Clause 14: The hydrogen production plant of any of the clauses, wherein the reactor further comprises a plurality of additional tubes that are positioned outside and around the first tube of each of the plurality of tube assemblies, wherein for each tube assembly of the plurality of tube assemblies, the additional tube is configured to direct the heating fluid stream in the second axial direction along an outside of the first tube relative to the central axis.

[0087] Clause 15: The hydrogen production plant of any of the clauses, further comprising: a first heat exchanger that is arranged to pre-heat the non-carbonaceous hydrogen source compound with a first portion of the heating fluid stream withdrawn from the reactor; and a second heating exchanger that is arranged topre-heat at least one stream flowing to the combustor with a second portion of the heating fluid stream withdrawn from the reactor.

[0088] Clause 16: The hydrogen production plant of any of the clauses, wherein the second heat exchanger is arranged to pre-heat the carbon dioxide recycled to the combustor.

[0089] Clause 17: The hydrogen production plant of any of the clauses, further comprising one or more separation devices that are configured to separate remaining hydrogen source compound from the product stream and recycle the remaining hydrogen source compound to the reactor.

[0090] Clause 18 : The hydrogen production plant of any of the clauses, wherein the one or more separation devices comprises: a first separation device configured to separate the product stream into a product H2 stream and first bottoms stream; and a second separation device configured to separate the first bottoms stream into a tops stream comprising the remaining hydrogen source compound and a second bottoms stream.

[0091] Clause 19: A method for hydrogen transport, the method comprising: (a) carrying out a storage reaction whereby hydrogen is reacted with one or more reactants to form an intermediate compound, said reacting being carried out at a first location; (b) transporting the intermediate compound from the first location to a second location that is physically separated from the first location; and (c) subjecting at least some of the intermediate compound to a decomposition reaction whereby hydrogen is formed and separated as a substantially pure product.

[0092] Clause 20: The method of any of the clauses, wherein one or both of the storage reaction and the decomposition reaction is carried out such that heating is provided by combustion of a hydrocarbon fuel, and wherein substantially all carbon dioxide formed by combustion of the hydrocarbon fuel is captured.

[0093] Clause 21 : The method of any of the clauses, wherein the intermediate compound is ammonia.

[0094] The preceding discussion is directed to various exemplary embodiments. However, one of ordinary skill in the art will understand that the examples disclosed have broad application, and that the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to suggest that the scope of the disclosure, including the claims, is limited to that embodiment.

[0095] The drawing figures are not necessarily to scale. Certain features and components may be shown exaggerated in scale or in somewhat schematic form and some details of conventional elements may not be shown in interest of clarity and conciseness.

[0096] The terms “about” or “substantially” as used can indicate that certain recited values or conditions are intended to be read as encompassing the expressly recited value or condition and also values that are relatively close or conditions that are recognized as being relatively close. For example, unless otherwise indicated, a value of “about” a certain number or “substantially” a certain value can indicate the specific number or value as well as numbers or values that vary therefrom ± by 10% or less, such as 5% or less, such as 4% or less, such as 3% or less, such as 2% or less, such as 1% or less, such as 0.5% or less, or such as 0.1% or less. Any one of such values may be used interchangeably with the words “about” and / or “substantially” as needed for clarity. Similarly, unless otherwise indicated, a condition that substantially exists can indicate the condition is met exactly as described or claimed or is within typical manufacturing tolerances or would appear to meet the required condition upon casual observation even if not perfectly meeting the requiredcondition. In some embodiments, the values or conditions can be defined as being express and, as such, the term “about” or “substantially” (and thus the noted variances) can be excluded from the express value. In addition, as used, the terms “axial” and “axially” generally mean along or parallel to a given axis (such as the central axis of a body or a port), while the terms “radial” and “radially” generally mean perpendicular to the given axis. For instance, an axial distance refers to a distance measured along or parallel to the axis, and a radial distance means a distance measured perpendicular to the axis.

[0097] Many modifications and other embodiments of the presently disclosed subject matter will come to mind to one skilled in the art to which this subject matter pertains having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the present disclosure is not to be limited to the specific embodiments described and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation.

[0098] Unless expressly stated otherwise, the steps in a method claim may be performed in any order. The recitation of identifiers such as (a), (b), (c) or (1), (2), (3) before steps in a method claim are not intended to and do not specify a particular order to the steps, but rather are used to simplify subsequent reference to such steps.

Claims

CLAIMS:

1. A process for hydrogen production comprising:(a) contacting a hydrogen source compound with a catalyst in a reactor, the hydrogen source compound being non-carbonaceous;(b) combusting a carbonaceous fuel in a combustor in the presence of carbon dioxide to form a heating fluid stream comprising the carbon dioxide and water;(c) passing the heating fluid stream into the reactor to heat the hydrogen source compound while the hydrogen source compound is contacting the catalyst without intermixing with the heating fluid stream and the hydrogen source compound;(d) withdrawing a product stream and the heating fluid stream from the reactor, the product stream comprising at least hydrogen; and(e) recycling at least some of the carbon dioxide from the heating fluid stream to the combustor after(d).

2. The process of claim 1 , wherein (a) further comprises flowing the hydrogen source compound through one or more tube assemblies positioned in the reactor, and wherein (c) further comprises contacting the heating fluid stream with the one or more tube assemblies within the reactor.

3. The process of claim 1, wherein (a) further comprises, for each tube assembly of the one or more tube assemblies, flowing the hydrogen source compound through a first annulus of the tube assembly; and wherein (d) further comprises, for each tube assembly of the one or more tube assemblies, flowing the product stream through an outlet tube of the tube assembly, the outlet tube being coaxially nested within a catalyst tube to define the first annulus between the outlet tube and the catalyst tube.

4. The process of claim 3, wherein (c) comprises, for each tube assembly of the one or more tube assemblies, flowing the heating fluid stream through a second annulus defined around the catalyst tube.

5. The process of any one of claims 1-4, further comprising:(f) splitting the heating fluid stream into a first portion and a second portion after (d);(g) preheating the hydrogen source compound with the first portion; and(h) preheating the one or more streams flowing to the combustor with the second portion.

6. The process of claim 5, wherein (h) further comprises preheating an oxidant stream, a fuel gas stream, and the carbon dioxide recycled to the combustor via (e) with the second portion.

7. The process of any one of claims 1-4, further comprising:(i) separating a hydrogen product stream from the product stream after (d);(j) separating remaining hydrogen source compound from the product stream after (d); and(k) recycling the remaining hydrogen source compound separated in (j) back to the reactor.

8. The process of any one of claims 1-4, wherein the hydrogen source compound comprises ammonia.

9. A hydrogen production plant comprising: a reactor configured to receive a non-carbonaceous hydrogen source compound, the reactor comprising a plurality of tube assemblies at least partially filled with a catalyst effective for decomposition of the non-carbonaceous hydrogen source compound into a product stream comprising at least hydrogen; a combustor configured to receive a hydrocarbon, an oxidant, and carbon dioxide and provide a heating fluid stream comprising carbon dioxide, the combustor being arranged for passage of the heating fluid stream to the reactor as a heating fluid; and one or more processing units arranged to receive the heating fluid stream from the reactor and to separate carbon dioxide from the heating fluid stream to provide at least a portion of the carbon dioxide received by the combustor.

10. The hydrogen production plant of claim 9, wherein each tube assembly of the plurality of tube assemblies comprises: a first tube; a second tube coaxially nested within the first tube along a central axis; and an annulus defined between the first tube and the second tube that is at least partially filled with the catalyst.

11. The hydrogen production plant of either claim 9 or 10, wherein for each tube assembly of the plurality of tube assemblies, the first tube and second tube are arranged so that: the non-carbonaceous hydrogen source compound is configured to flow in a first axial direction along the central axis within the annulus; and the product stream is configured to flow axially in a second axial direction along the central axis within the second tube, the second axial direction being opposite the first axial direction.

12. The hydrogen production plant of claim 11, wherein the reactor further comprises: a first tube sheet that is configured to at least partially define a first collection space in the reactor that is in fluid communication with the second tube of each tube assembly of the plurality of tube assemblies; anda second tube sheet that is configured to at least partially define a second collection space in the reactor that is in fluid communication with the annulus of each tube assembly of the plurality of tube assemblies.

13. The hydrogen production plant of claim 11 , wherein the reactor further comprises one or more baffles that are configured to direct the heating fluid stream in a serpentine flow direction around an outside of the plurality of tube assemblies.

14. The hydrogen production plant of claim 11, wherein the reactor further comprises a plurality of additional tubes that are positioned outside and around the first tube of each of the plurality of tube assemblies, wherein for each tube assembly of the plurality of tube assemblies, the additional tube is configured to direct the heating fluid stream in the second axial direction along an outside of the first tube relative to the central axis.

15. The hydrogen production plant of either claim 9 or 10, further comprising: a first heat exchanger that is arranged to preheat the non-carbonaceous hydrogen source compound with a first portion of the heating fluid stream withdrawn from the reactor; and a second heating exchanger that is arranged to preheat at least one stream flowing to the combustor with a second portion of the heating fluid stream withdrawn from the reactor.

16. The hydrogen production plant of claim 15, wherein the second heat exchanger is arranged to preheat the carbon dioxide recycled to the combustor.

17. The hydrogen production plant of claim 16, further comprising one or more separation devices that are configured to separate remaining hydrogen source compound from the product stream and recycle the remaining hydrogen source compound to the reactor.

18. The hydrogen production plant of claim 17, wherein the one or more separation devices comprises: a first separation device configured to separate the product stream into a product H2stream and first bottoms stream; and a second separation device configured to separate the first bottoms stream into a tops stream comprising the remaining hydrogen source compound and a second bottoms stream.

19. A method for hydrogen transport, the method comprising:(a) carrying out a storage reaction whereby hydrogen is reacted with one or more reactants to form an intermediate compound, said reacting being carried out at a first location;(b) transporting the intermediate compound from the first location to a second location that is physically separated from the first location; and(c) subjecting at least some of the intermediate compound to a decomposition reaction whereby hydrogen is formed and separated as a substantially pure product.

20. The method of claim 19, wherein one or both of the storage reaction and the decomposition reaction is carried out such that heating is provided by combustion of a hydrocarbon fuel, and wherein substantially all carbon dioxide formed by combustion of the hydrocarbon fuel is captured.

21. The method of either claim 19 or 20, wherein the intermediate compound is ammonia.

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