Systems & methods for thermally decomposing hydrocarbons

Abstract

Systems and methods for producing hydrogen. The system includes a fluidized bed reactor for thermally decomposing a hydrocarbon feed to produce hydrogen case and carbon. The fluidized bed is in communication with a regenerator for converting spent catalyst particles to heated regenerated catalysts in a multilayer bed. The heated regenerated catalysts are returned to reactor in an amount sufficient to provide energy for thermally decomposing the hydrocarbon feed.

Description

SYSTEMS & METHODS FOR THERMALLY DECOMPOSINGHYDROCARBONSFIELD OF DISCLOSURE

[0001] The present disclosure relates generally to the thermal decomposition of hydrocarbons, and more particularly but not by way of limitation, to systems and methods for thermally decomposing a hydrocarbon feed into hydrogen gas using a fluidized bed reactor and multilayer fluidized bed regenerator.BACKGROUND

[0002] Hydrogen is used in many different chemical and industrial processes. Hydrogen is also an important fuel for future transportation and other uses as it does not generate any carbon dioxide emissions during use.

[0003] There are several ways of producing hydrogen. For example, subjecting water to electrolysis allows for carbon dioxide-free production of hydrogen, as long as the energy used for the electrolysis is obtained from non-hydrocarbon sources, such as wind or solar energy. If the hydrogen is generated without using hydrocarbons it is often referred to as green hydrogen. At present, processes based on electrolysis can be very expensive.

[0004] Another process generally used for producing hydrogen is steam reforming. In steam reforming, a methane (CH4) comprising feed gas is reacted with steam in the presence of a suitable steam reforming catalyst. Because steam reforming is a strongly endothermic reaction it requires energy, especially heat, which can be generated by combustion of fuel or natural gas. Disadvantageously, fuel and natural gas combustion results in low pressure exhaust gases with a low concentration of carbon dioxide. The capture of carbon dioxide from such exhaust gases requires a separation process to concentrate the carbon dioxide and pressurization for sequestration. A further disadvantage in steam reforming is the feed needs to be treated thoroughly before entering the reformer. This means that extensive gas treatment or feed treatment is required adding to the cost and complexity of a plant using reforming to produce synthesis gas. Finally, the synthesis gas, and consequently hydrogen, is produced at relatively low pressures that require compression for further use.

[0005] Another process that can be used to produce hydrogen is the thermal decomposition (also referred to as temperature-induced dissociation, the pyrolysis or cracking) of hydrocarbons. In this process, natural gas is decomposed at high temperatures ranging from 1200°C to 1800°C to form hydrogen and carbon black, where air, oxygen or steam are preferably admixed to both modify the carbon black formed and maintain the reaction temperature. In order to reduce the high reaction temperatures, catalyst-supported processes have been proposed. While transition metal catalysts exhibit high activities in terms of methane decomposition, carbon layers deposit on the surfaces of the catalysts and therefore have to be continuously removed and regenerated. In most cases, the formed carbon coat is burned off under air access in order to regenerate the catalyst.

[0006] In view of the above, it is an aim of the present disclosure to provide an improved system and process for producing hydrogen that overcomes at least some of the above-mentioned drawbacks of conventional systems and processes, for example heat management of the system and removal of carbon from the reactor.SUMMARY

[0007] The present disclosure relates to systems and methods for thermally decomposing a hydrocarbon feed into hydrogen gas and carbon using a reactor and a multilayer bed regenerator. In one configuration of the present system for producing hydrogen gas from thermal decomposition of a hydrocarbon, the system includes: a) a reactor having an upper portion and a lower portion and a reactor chamber therein; b) a bed of catalyst particles disposed in the reactor chamber; c) a regenerator having an upper portion in fluid communication with the lower portion of the reactor via a first conduit and a lower portion in fluid communication with the upper portion of the reactor via a second conduit and a regeneration chamber therein; and d) a multilayer bed disposed in the regeneration chamber having a top layer, a bottom layer and at least one layer in between, where each layer of the bed is separated from one another by a permeable grid. The reactor is configured to receive the hydrocarbon feed and thermally decompose the hydrocarbon feed to produce spent catalyst particles and an effluent stream comprising hydrogen gas. The regenerator is configured to receive an oxidant and at least a portion of the spent catalyst particles from the lower portion of the reactor and react the spent catalyst particles and oxidant to produce heated regenerated catalyst particles. The regenerator is further configured to transfer at least a portion of the heated regenerated catalyst particles to the upper portion of the reactor. Themultilayer bed is configured to receive the spent catalyst particles at the top layer of the multilayer bed and each permeable grid is configured to allow the spent catalyst particles to travel downward sequentially from the top layer of the multilayer bed to a bottom layer of the multilayer bed. Finally, at least 70% of energy needed for thermally decomposing the hydrogen feedstock in the reactor chamber is from heat provided by the portion of the heated regenerated catalyst particles returned to the reactor.

[0008] In one implementation of the present method for producing hydrogen gas from thermal decomposition of a hydrocarbon feed, the method comprises: feeding the hydrocarbon feed into a reactor chamber of a reactor; thermally decomposing the hydrocarbon feed in a fluidized bed of catalyst particles disposed in the reactor chamber to produce spent catalyst particles and an effluent stream comprising hydrogen gas; removing at least a portion of the spent catalyst particles from the reactor and transferring the spent catalyst particles to a top layer of a multilayer bed disposed in a regenerator, wherein each layer of the multilayer bed is separated from one another by a grid configured to allow the spent catalyst particles to travel downward from the top layer of the multilayer bed; reacting the spent catalyst particles in the multilayer bed with an oxidant to produce heated regenerated catalyst particles; and returning a portion of the heated regenerated catalyst particles to the reactor chamber. Finally, at least 70% of energy needed for thermally decomposing the hydrogen feeds in the reactor chamber is from heat provided by the portion of the heated regenerated catalyst particles returned to the reactor.

[0009] In another configuration the system for producing hydrogen gas from thermal decomposition of a hydrocarbon includes: a) a reactor having an upper portion and a lower portion and a reactor chamber therein; b) a bed of catalyst particles disposed in the reactor chamber; c) a regenerator having an upper portion in fluid communication with the lower portion of the reactor via a first conduit and a lower portion in fluid communication with the upper portion of the reactor via a second conduit and a regeneration chamber therein; d) a multilayer bed disposed in the regeneration chamber having a top layer, a bottom layer and at least one layer in between, where each layer of the bed is separated from one another by a permeable grid; and e) an electrical heating apparatus operable to receive a gas and apply thermal energy to the gas to produce a heated gas. The reactor is configured to receive the hydrocarbon feed and thermally decompose the hydrocarbon feed to produce spent catalyst particles and an effluent stream comprising hydrogen gas. The regenerator is configured to receive an oxidant and at least a portion of the spent catalystparticles from the lower portion of the reactor and react the spent catalyst particles and heated gas to produce heated regenerated catalyst particles. The regenerator is further configured to transfer at least a portion of the heated regenerated catalyst particles to the upper portion of the reactor. The multilayer bed is configured to receive the spent catalyst particles at the top layer of the multilayer bed and each permeable grid is configured to allow the spent catalyst particles to travel downward sequentially from the top layer of the multilayer bed to a bottom layer of the multilayer bed. Finally, at least 70% of energy needed for thermally decomposing the hydrogen feedstock in the reactor chamber is from heat provided by the portion of the heated regenerated catalyst particles returned to the reactor.

[0010] In another implementation the method for producing hydrogen gas from thermal decomposition of a hydrocarbon feed includes: feeding the hydrocarbon feed into a reactor chamber of a reactor; thermally decomposing the hydrocarbon feed in a fluidized bed of catalyst particles disposed in the reactor chamber to produce spent catalyst particles and an effluent stream comprising hydrogen gas; removing at least a portion of the spent catalyst particles from the reactor and transferring the spent catalyst particles to a top layer of a multilayer bed disposed in a regenerator, wherein each layer of the multilayer bed is separated from one another by a permeable grid configured to allow the spent catalyst particles to travel downward from the top layer of the multilayer bed; reacting the spent catalyst particles in the multilayer bed with a heated gas produced by applying thermal energy to a gas in an electrical heating apparatus to produce heated regenerated catalyst particles; and returning a portion of the heated regenerated catalyst particles to the reactor chamber. At least 70% of energy needed for thermally decomposing the hydrogen feeds in the reactor chamber is from heat provided by the portion of the heated regenerated catalyst particles returned to the reactor.BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The following drawing illustrates by way of example and not limitation.

[0012] FIG. 1 depicts a schematic diagram of a first example of a system for thermally decomposing a hydrocarbon feed using a fluidized bed reactor and a multi-layer fluidized bed regenerator to produce hydrogen.

[0013] FIG. 2 depicts a schematic diagram of a second example of a system for thermally decomposing a hydrocarbon feed using a fluidized bed reactor and a multi-layer fluidized bed regenerator to produce hydrogen.

[0014] FIGS. 3 and 4 depict flow diagrams of methods for thermally decomposing hydrocarbon feed into hydrogen according to embodiments.DETAILED DESCRIPTION

[0015] In various embodiments, systems and methods are described for converting a hydrocarbon feed to hydrogen by thermal decomposition. In one embodiment, the conversion of the hydrocarbon feed to hydrogen may be performed in a fluidized bed reactor containing a layer of catalyst particles. The fluidized bed reactor is in fluid communication with a regenerator. The regenerator receives spent catalyst particles from the fluidized bed reactor and converts the spent catalyst particles to heated regenerated catalyst particles and returns a portion of the heated regenerated catalyst particles to the fluidized bed reactor where energy (heat) from the portion of the returned regenerated catalyst particles provides energy for thermally decomposing the hydrogen feedstock into hydrogen. The regenerator contains a plurality of layers or beds, each layer or bed is separated from adjacent layers or beds by a permeable grid. In order to form a plurality of fluidized beds in the regenerator, the permeable grids (or mesh tray or another type of sufficiently porous support) are configured to allow a fluidizing gas to pass through the permeable grid while retaining a substantial majority of catalyst particles in the fluidized bed. One or more openings or conduits provided in the permeable grid allows a portion of catalyst particles to fall from a fluidized bed at a higher elevation onto the top of the layer of catalyst particles below. The plurality of layers allows the regenerator to exhibit improved heat transfer and heat management. In particular, segregation of catalyst particles within the plurality of beds produces a temperature gradient with the top layer of the bed having the lowest temperature and the bottom layer of the bed having the highest temperature. As the cooler catalyst particles travel downward through each layer of the bed, they are capable of exchanging heat with the upwardly flowing fluidized gas. In addition to better heat recovery, the energy gradient obtained over the regenerator beds may also lead to a reduced amount of heated regenerated catalyst particles needed to be displaced between the reactor and regenerator in order to sustain the endothermic thermal decomposition reaction of the hydrocarbon feed in the reactor.

[0016] As used herein, the term “coupled” is defined as connected, although not necessarily directly, and not necessarily mechanically; two items that are “coupled” may be unitary with each other. The terms “a” and “an” are defined as one or more unless this disclosure explicitly requires otherwise. The term “substantially” is defined as largely but not necessarily wholly what is specified (and includes what is specified; e.g., substantially 90 degrees includes 90 degrees and substantially parallel includes parallel), as understood by a person of ordinary skill in the art. In any embodiment of the present apparatuses, kits, and methods, the term “substantially” may be substituted with “within [a percentage] of’ what is specified, where the percentage includes 0.1, 1, 5, and / or 10 percent.

[0017] The terms “comprise” (and any form of comprise, such as “comprises” and “comprising”), “have” (and any form of have, such as “has” and “having”), “include” (and any form of include, such as “includes” and “including”) and “contain” (and any form of contain, such as “contains” and “containing”) are open-ended linking verbs. As a result, an apparatus or kit that “comprises,” “has,” “includes” or “contains” one or more elements possesses those one or more elements, but is not limited to, possessing only those elements. Likewise, a method that “comprises,” “has,” “includes” or “contains” one or more steps possesses those one or more steps, but is not limited to, possessing only those one or more steps.

[0018] Further an apparatus, device or system that is configured in a certain way is configured in at least that way, but it can also be configured in other ways than those specifically described.

[0019] Any embodiment of any of the present systems and methods can consist of or consist essentially of - rather than comprise / include / contain / have - any of the described steps, elements, and / or features. Thus, in any of the claims, the term “consisting of’ or “consisting essentially of’ can be substituted for any of the open-ended linking verbs recited above, in order to change the scope of a given claim from what it would otherwise be using the open-ended linking verb.

[0020] The term “fluidized bed reactor” is given its conventional meaning in the art and is used to refer to a reactor comprising a chamber that can contain a granular solid material (e.g., catalyst particles). A fluid (e.g., a gas or a liquid) can be passed through the granular solid material at velocities sufficiently high to suspend the granular solid material and cause it to behave as though it were a fluid. Examples of fluidized bed reactors are described in Kirk-Othmer Encyclopedia of Chemical Technology, Vol. 11, Hoboken, N.J.: Wiley-Interscience, 2001, pages 791-825, which is incorporated herein by reference, and include the following:a "circulating fluidized bed reactor” is also given its conventional meaning in the art and is used to refer to a fluidized bed reactor in which the granular solid material is passed out of the reactor, circulated through a line in fluid communication with the reactor, and recycled back into the reactor; a “bubbling fluidized bed reactor” and “turbulent fluidized bed reactor” are also given their conventional meaning in the art. In a bubbling fluidized bed reactor, the fluid stream used to fluidize the granular solid material operates at a sufficiently low flow rate such that bubbles and voids are observed within the volume of the fluidized bed during operation. In a turbulent fluidized bed reactor, the flow rate of the fluid stream used to fluidize the granular material is higher than that employed in a bubbling fluidized bed reactor, and therefore bubbles and voids are not observed within the volume of the fluidized bed during operation.

[0021] “Fluid communication” refers to passage of gases and / or liquids between elements of a system. It is noted that solid particles can be entrained in a fluid so solids may also be transported via fluid communication.

[0022] The term “spent catalyst particles” refers to catalyst particles that have been exposed to a hydrocarbon feed to generate hydrogen gas. The spent catalyst particles may have coke deposited thereon and may include partially coked catalyst particles as well as fully coked catalyst particles. The amount of coke deposited on the spent catalyst particles may be greater than the amount of coke remaining on regenerated catalyst particles following regeneration.

[0023] The term “regenerated catalyst particles” refers to spent catalyst particles that have been regenerated in the regenerator by combustion with an oxidant to remove at least a portion of the coke from the spent catalyst particles to restore at least a portion of the catalytic activity of the spent catalyst particles.

[0024] The term “hydrocarbon feed” includes, but is not limited to, methane, biogas, digester off gas, landfill gas, coal bed methane, pipeline natural gas, natural gas with residual light hydrocarbon liquids and other methane-rich process streams.

[0025] Some details associated with the various configurations and implementations of the present systems and methods are described above, and other details are described below.

[0026] Referring now to the drawing, FIG. 1 depicts a schematic diagram of an example of a hydrogen gas production system 100 of the present disclosure. In the depicted example, system 100 includes a reactor 102 having an upper portion 103, a lower portion 105 and a reactor chamber104 therein. The reactor chamber 104 includes a bed of catalyst particles 106 disposed therein. The reactor 102 also includes a hydrocarbon feed inlet 108 in fluid communication with the reactor chamber 104. The reactor 102 may also include a distributor 110 in the reactor chamber 104, such as at the lower portion 105 (below the bed of catalyst particles 106) of the reactor chamber 104. The hydrocarbon feed inlet 108 may be fluidly connected to the distributor 110 to distribute a hydrocarbon feed across a lateral plane or cross-section of the reaction chamber 104. The reactor chamber 104 may be configured to be initially heated by combustion (internally or externally), such as by use of a dedicated start-up fired heater to increase the air / oxygen temperature entering the system or by fuel injection (e.g., natural gas) from the regeneration side of the system. During operation, the reactor chamber 104 and bed of catalyst particles 106 disposed therein are initially heated to at least the temperature at which the hydrocarbon feed will thermally decompose to form hydrogen gas and carbon as the hydrocarbon feed flows upwardly through the fluidized bed.

[0027] The inner dimensions of the walls of the reactor 102 form the reactor chamber 104. The reactor chamber 104 includes a portion holding the bed of catalyst particles 106. The reactor chamber 104 may include a headspace above the bed of catalyst particles 106. The headspace may be in fluid communication with a reactor outlet conduit 112. In some embodiments, the lateral dimensions of the reactor chamber 104 may remain constant, narrow or widen as a function of the height of the reactor chamber 104.

[0028] The bed of catalyst particles 106 includes a plurality of catalyst particles in the reactor chamber 104. The catalyst particles may include one or more of a supported metal catalyst, a carbon-based catalyst or inert material. The metal catalysts may include, but are not limited to, transition metals or metal oxides such as nickel, iron or cobalt which are supported on a porous substrate such as silica or alumina. Carbon-based catalysts may include, but are not limited to, carbon black, activated carbon, graphite, diamond powder, carbon nanotubes, glassy carbon, fullerene soot, acetylene black, coal, char and mesoporous carbon (CMK-3). Inert materials may include, but are not limited to, silica, alumina and silicon carbide. The catalyst particles may have a particle size ranging from about 10-1000 pm, or from about 50-200 pm.

[0029] The bed of catalyst particles 106 includes a fluidized bed. The bed of catalyst particles 106 may be fluidized at least by the hydrocarbon feed gas flowing upward there through. In some embodiments, an inert gas (e.g., nitrogen) may alternatively or additionally be flowed upward through the bed of catalyst particles 106 to fluidize the catalyst particles. In other embodiments,hydrogen and oxygen (e.g., air) may alternatively or additionally be flowed upward through the bed of catalyst particles, such as to combust within the bed of catalyst particles 106. In some examples, the gases flowing upward may change during operation, such as starting the fluidization with hydrogen and oxygen or an inert gas and switching over to the hydrocarbon feed when the fluidized bed is at a selected temperature. The composition of the gas flowing through the bed of catalyst particles 106 may change as a function of height within the bed of particles, such as having a higher hydrogen content in upper portions of the bed. For example, as the hydrocarbon feed is thermally decomposed the composition of the fluidizing gas will change to hydrogen or mixtures of hydrocarbons and hydrogen.

[0030] In some embodiments, the reactor 102 includes a stripping section 114 for separating hydrocarbons from the spent catalyst particles prior to their transfer to a regenerator 120. The spent catalyst particles from the reactor chamber 104 travel (by gravity) to the lower portion of the reactor where the stripping section 114 is positioned. The stripping section 114 includes a stripping gas inlet 116 into which a suitable stripping gas, such as an inert gas (e.g., nitrogen), can be introduced. The stripping section 114 may include several baffles or structured packing (not shown) over which the downwardly traveling spent catalyst particles pass counter-currently to the upwardly flowing stripping gas. The stripping gas is configured to “strip” or remove any hydrocarbons that remain in the spent catalyst pores or between spent catalyst particles.

[0031] System 100 also includes regenerator 120 having an upper portion 122, a lower portion 123 and a regeneration chamber 124 therein. The regenerator 120 is in fluid communication with the reactor 102 by a first conduit 118 and a second conduit 119. In one embodiment, the upper portion 122 of the regenerator 120 is in fluid communication with the lower portion 105 of the reactor 102 by the first conduit while the lower portion 123 of the regenerator 120 is in fluid communication with the upper portion 103 of the reactor 102 by the second conduit 119.

[0032] The regenerator 120 also includes an oxidant feed inlet 128 in fluid communication with the regeneration chamber 124. The regenerator 120 may also include a distributor 130 in the regeneration chamber 124, such as at the lower portion, for example below multilayer bed 126, of the regeneration chamber 124. The oxidant feed inlet 128 may be fluidly connected to distributor 130 which is configured to distribute the oxidant across a lateral plane or cross-section of the regeneration chamber 124.

[0033] The inner dimensions of the walls of the regenerator 120 form the regeneration chamber 124. As noted above, the regeneration chamber 124 includes multilayer bed 126. The multilayer bed 126 includes a top layer, a bottom layer and at least one layer in between. Each layer of the multilayer bed 126 is separated from one another by a permeable grid 132 mounted within the regenerator 120 along the regeneration pathway. The permeable grids 132 are configured to allow the spent catalyst particles received from the reactor 102 travelling (by gravity) downward to sequentially to travel from the top layer of the multilayer bed 126 to the bottom layer of the multilayer bed 126. The permeable grids 132 typically have a plurality of openings of various sizes and dimensions. The distribution of the regenerated catalyst particles within each layer can be controlled by: adjusting the opening ratio of each grid; the dimension or size of the openings; and the relative height of each bed to establish a concentration density gradient for both the regenerated catalyst particles and oxidant feed.

[0034] The regeneration chamber 124 may also include a headspace above the top layer of the multilayer bed 126. The headspace may be in fluid communication with a flue gas outlet conduit 144. In some embodiments, the lateral dimensions of the regeneration chamber 124 may remain constant, narrow or widen as a function of the height of the regeneration chamber 124.

[0035] In some embodiments, the regenerator 120 also includes a stripping section 134 positioned at the lower portion 123 of the regenerator 120. The stripping section 134 includes a stripping gas inlet 136 into which a suitable stripping gas, such as an inert gas (e.g., nitrogen), is introduced. The stripping section 134 may include several baffles or structured packing (not shown) over which the downwardly flowing regenerated catalyst particles pass counter-currently to the upwardly flowing stripping gas. The stripping gas is configured to “strip” or remove any residual oxidant that remains in the regenerated catalyst pores or between the regenerated catalyst particles.

[0036] The first conduit 118 of system 100 is configured to receive a portion of the spent catalyst particles from the reactor 102 and convey the portion to the regeneration chamber 124, for example above the top layer of the multilayer bed 126. A first lifting gas, such as air or an inert gas (e.g., nitrogen), may be introduced into a first lifting gas inlet 109 and used to pneumatically convey the portion of spent catalyst particles from the reactor 102 to the regeneration chamber 124. Similarly, the second conduit 119 of system 100 is configured to receive a portion of the regenerated catalyst particles from the regenerator 120 and convey the portion to the reactorchamber 104, for example above the bed of catalyst particles 106. A second lifting gas, such as hydrocarbon feed (e.g., natural gas) or an inert gas (e.g., nitrogen), may be introduced into a second lifting gas inlet 129 and used to pneumatically convey the portion of regenerated catalyst particles from the regenerator 120 to the reactor chamber 104.

[0037] The system 100 may also include a solids separator 150. The solids separator 150 is in fluid communication with the reactor chamber 104 via reactor outlet conduit 112 and is configured to receive an effluent stream including hydrogen gas, unreacted hydrocarbon feed, carbon product and catalyst fines from the reactor chamber 104 and recover the carbon product and catalyst fines from the effluent stream. Accordingly, the solids separator 150 may have a gas outlet 152 for removing unreacted hydrocarbon feed and hydrogen gas and a solids outlet 154 for removing the carbon product and catalyst fines. Examples of the solids separator 150 include, but are not limited to, a gravity separator, cyclone, electrostatic separator, filter or wet scrubber.

[0038] The system 100 may further include separator 160. Separator 160 is in fluid communication with the first solids separator 150 via solids outlet 154 and is configured to receive the catalyst fines and carbon product and separate the catalyst fines from the carbon product with the recovered catalyst fines being returned to the reactor chamber 104 via catalyst conduit 162. The carbon product 164 is taken from the dipleg of the cyclone. In some embodiments the carbon product can be taken from conduits 118, conduit 119, or extracted from stripping sections 105, stripping section 134 or any combination thereof.

[0039] In another embodiment, the system 100 includes a gas separator (not shown). The gas separator is in fluid communication with the solids separator 150 via the gas outlet 152. The gas separator is configured to receive a gas stream from the solids separator 150 and separate hydrogen from the gas stream. In some embodiments, the gas separator may be, but is not limited to, a gas separation membrane, a pressure swing adsorption system or a cryogenic adsorption (or absorption) unit.

[0040] During operation, hydrocarbon feed (for e.g., natural gas) is introduced into the reactor 102 via feed inlet 108. In the configuration shown in FIG. 1, the reactor 102 is configured as an updraft reactor where the feed inlet 108 is positioned at or near the bottom of the reactor 102. The feed inlet 108 may be fluidly connected to distributor 110 to supply the hydrocarbon feed. The distributor 110 may be a manifold for splitting a single stream into a plurality of streams. For example, the distributor 110 may diffuse the single stream of the hydrocarbon feedinto a plurality of streams across a lateral cross-section or plane of the reaction chamber 104. In some embodiments, the distributor 110 may be a sparger, distributor plate or any other type of orifice used to introduce the hydrocarbon feed into the bottom of the reaction chamber 104.

[0041] The reactor 102 is operably coupled to a feed supply, such as a natural gas supply or another hydrocarbon feed via the feed inlet 108. The feed supply may include one or more of a steam supply, an oxygen supply, an air supply, or the like for mixing with the natural gas to form the hydrocarbon feed. The feed inlet 108 may include one or more conduits capable of delivering hydrocarbon feed (e.g., natural gas) at selected pressures, without leaking or rupturing.

[0042] As the hydrocarbon feed flows upwards through the bed of catalyst particles 106, the temperature in the bed of catalyst particles 106 is at or above the thermal decomposition temperature of the hydrocarbon feed (e.g., methane) allowing the hydrocarbon feed to at least partially thermally decompose to form hydrogen gas and carbon. In some embodiments, the temperature in the reactor chamber 102 may range from about 500°-1500°C or from about 800°- 1100°C. The pressure within the reactor chamber may range from about 1-100 bar or from about 20-50 bar. The effluent stream containing the hydrogen gas and carbon product, and which may also contain unreacted hydrocarbon feed and catalyst fines, may be collected and removed from the reactor chamber 104 via reactor output conduit 112.

[0043] The effluent stream may then be routed to the solids separator 150 where the unreacted hydrocarbon feed and hydrogen gas are separated from the carbon product and catalyst fines. The solids separator 150 may include a residence chamber for allowing the carbon product and catalyst fines to fall from the effluent stream, a cyclone separator, an electrostatic precipitation apparatus, or by the use of a filter. Such filters may include a “candle” filter with ceramic material, a metallic filter with pores, or a fabric filter (e.g., a bag house). The solids separator 150 may also include one or more filters for preventing the carbon product and catalyst fines from passing through the gas outlet 152. The solids outlet 154 may be at or near the bottom of the solids separator 150. The carbon product and catalyst fines may then be transferred from the solids outlet 154 to separator 160 where the catalyst fines may be separated from the carbon product with the catalyst fines being transferred back to the reactor chamber 104 via conduit 162 and the carbon product 164 being available for other uses (such as described above) or sale. The gas stream exiting gas outlet 152 may be routed to the gas separator where hydrogen is separated from the gasstream. The hydrogen product may be used in various applications, for example, in the production of methanol or ammonia.

[0044] Some of the carbon produced via thermal decomposition in the reactor chamber 104 may deposit on the catalyst particles within the fluidized bed forming spent catalyst particles. The spent catalyst particles in the fluidized bed travel (by gravity) downward and they increase in size due to the deposition of carbon thereon and may pass through the stripping section 114 where they are contacted by an upwardly flowing stripping gas before being transferred to the first conduit 118 and conveyed to the regeneration chamber 124 by the first lifting gas (fed to the first conduit 118 via first lifting gas inlet 109) where the spent catalyst particles are contacted with an oxidant to form hot regenerated catalyst particles and heat from combustion. The first lifting gas may be, but is not limited to, air or an inert gas (e.g., nitrogen).

[0045] An oxidant may be fed to the regenerator 120 via the oxidant feed inlet 128. The oxidant may originate from any source including, for example, a tank of oxygen, atmospheric air, recycled exhaust gas (e.g., carbon dioxide), or steam. Mixtures of oxidants may also be used.

[0046] As discussed above, the multilayer bed 126 includes a number of layers or stages of fluidized beds which are separated from one another by perforated grids 132. The spent catalyst particles are pneumatically conveyed to the top layer of the multilayer bed 126 by the first lifting gas. At least a portion of the spent catalyst particles in the top layer are contacted by the ascending oxidant to generate preliminary regenerated catalyst particles. The preliminary regenerated catalyst particles flow downward through the perforated grid 132 to the next stage or layer of fluidized bed where they are further contacted by the ascending oxidant and in turn pass into the next stages or layers of fluidized bed until eventually travelling to and through the bottom layer of the multilayer bed as regenerated catalyst particles. Regeneration in the multilayer fluidized bed 126 may enhance from the top stage or layer to the bottom stage or layer and may reach at least about 90% regeneration of the spent catalyst particles in the bottom layer.

[0047] The size of the fluidized beds can be independently selected in any convenient manner. This can allow the fluidized beds in the regenerator to have different sizes. Using different sized beds can change the average residence time for catalyst particles and / or gases within a fluidized bed which can allow for independent control of average residence time.

[0048] The flow rate of oxidant into the oxidant feed inlet 128 may be selected so that the fluidizing gas velocity is greater than the minimum fluidization velocity for the spent catalystparticles in any of the beds in the sequential plurality of fluidized beds. The minimum fluidization velocity for the spent catalyst particles can be readily estimated based on the density and particle size of each type of particle and based on the density and viscosity of the oxidant.

[0049] The second conduit 119 and second lifting gas (fed to the second conduit 119 via second lifting gas inlet 129) are used to return at least a portion of heated regenerated catalyst particles from the bottom of the regenerator back to the upper portion of the reactor 102. As the downwardly travelling spent catalyst particles are contacted by the upwardly flowing oxidant, the coke deposits are oxidized generating heat and hot flue gas. The heated regenerated catalyst particles pass through the bottom layer of the multilayer bed 126 and are subsequently contacted with a stripping gas in the stripper section 134. The stripping gas may be, but is not limited to, an inert gas (e.g., nitrogen). The heated regenerated catalyst particles next enter the second conduit 119 and are pneumatically conveyed by the second lifting gas to the upper portion of the reactor 102 and into the fluidized catalyst particles 106 in the reactor chamber 104. In some embodiments, the second lifting gas may be an inert gas (e.g., nitrogen) or the hydrocarbon feed. The returned heated regenerated catalyst particles provide energy (heat) for the thermal decomposition of the hydrocarbon feed in the reactor chamber 104. In some embodiments, the heated regenerated catalyst particles provide at least 70%, or at least 80%, or at least 90%, or at least 95%, or substantially all the energy (heat) necessary to thermally decompose the hydrocarbon feed in the reactor chamber 104. In some embodiments, the hot flue gas containing carbon dioxide and catalyst fines may be removed from the regeneration chamber 124 and captured via flue gas outlet 144.

[0050] The hot flue gas may then be routed to flue gas separator 170 where the catalyst fines are separated from carbon dioxide and carbon monoxide. The flue gas separator 170 may include a residence chamber allowing the catalyst fines to fall from the hot flue gas. The flue gas separator 170 may also include one or more filters for preventing the catalyst fines from passing through flue gas separator outlet 172. The catalyst fines may then be transferred from the flue gas separator 170 back to the regenerator 120 via conduit 171. Carbon dioxide exiting flue gas separator 170 via flue gas separator outlet 172 may be separated from carbon monoxide and captured using a liquid or by other conventional methods.

[0051] FIG. 2 depicts a schematic diagram of a second example of a hydrogen gas production system 200 of the present disclosure. System 200 is similar to system 100 with the exception beingthe required energy to support the endothermic reaction in reactor 102 is substantially introduced using electrical energy (which in some embodiments may be generated by renewable energy) thus avoiding the need for combustion / oxidation and the carbon monoxide and carbon dioxide production that is associated with it.

[0052] In one embodiment, system 200 includes an electrical heating apparatus 176 operable to receive a gas 174 and apply thermal energy to the gas 174 to produce a heated gas 128. The regenerator is configured to receive the heated gas 128 and (similar to system 100) at least a portion of the spent catalyst particles from the lower portion of the fluidized bed reactor 102 to produce heated regenerated catalyst particles and to transfer at least a portion of the heated regenerated catalyst particles via conduit 119 to the upper portion or lower portion (or a portion therebetween) of the fluidized bed reactor 102. The amount of thermal energy applied to the gas 174 is an amount sufficient such that the portion of heated regenerated catalyst particles from the bottom of the regenerator that is returned back to the fluidized bed reactor 102 via conduit 119 is at a temperature sufficient to heat the hydrocarbon feed in fluidized bed reactor 102 causing it to thermally decompose and form hydrogen gas and carbon. In some embodiments, the heating apparatus 176 may be an electrical heater, a thermal battery or a rotodynamic heater (as shown FIG. 2).

[0053] In some embodiments, the gas 174 may be an inert gas (e.g., hydrogen, nitrogen, argon, helium), carbon dioxide and or carbon dioxide leaving the flue gas separator 170 via outlet 174, an oxidant (oxygen, pure or diluted) or any mixture thereof.

[0054] In still further embodiments, the reactor chamber 104 for system 200 may be configured to be initially heated as described above for system 100 in order for the thermal decomposition of the hydrocarbon feed to begin or it may be configured to be initially heated using electrical energy in order to further reduce the carbon dioxide footprint of system 200. Such electrical heating may include heating by impedance (e.g., where electricity flows through the walls of the reactor 102), heating via ohmic heating, plasma, electric arc, radio frequency (RF), infrared (IR), UV, and / or microwaves, heating by radiation from an electrically heated element, heating by induction (e.g., an oscillating magnetic field) or heating by some combination of the above.

[0055] One method for thermally decomposing the hydrocarbon feed into hydrogen gas is depicted in FIG. 3. The method 300 includes a first block 310 of feeding the hydrocarbon feed into a reactor chamber of a reactor; a second block 320 of thermally decomposing the hydrocarbon feed in a fluidized bed of catalyst particles disposed in the reactor chamber to produce an effluentstream comprising hydrogen gas and spent catalyst particles; a third block 330 of removing at least a portion of the spent catalyst particles from the reactor and transferring the spent catalyst particles to a top layer of a multilayer bed disposed in a regenerator; a fourth block 340 of reacting the spent catalyst particles with a counter-current flowing oxidant in the multilayer bed to produce heated regenerated catalyst particles; and a fifth block 350 of returning a portion of the heated regenerated catalyst particles to the reactor chamber. As described above, each layer of the multilayer bed is separated from one another by a grid configured to allow the heated regenerated catalyst particles to travel downward (by gravity) from the top layer of the multilayer bed to a bottom layer of the multilayer bed. The bottom layer of the multilayer bed is in fluid communication with a conduit which is configured to pneumatically convey at least a portion of the heated regenerated catalyst particles to upper portion of the reactor and into the reactor chamber. The amount of heated regenerated catalyst particles returned to the reactor chamber is an amount sufficient to sustain the thermal decomposition of the hydrogen feedstock in the reactor chamber.

[0056] The method may also include a step of removing the effluent stream from the reactor chamber via a reactor outlet conduit. The reactor outlet conduit may be in fluid communication with a separator. Thus, in another step, the effluent stream may be transferred to the separator where hydrogen gas is separated from the effluent stream.

[0057] Another method for thermally decomposing the hydrocarbon feed into hydrogen gas is depicted in FIG. 4. The method 400 includes a first block 410 of feeding the hydrocarbon feed into a reactor chamber of a reactor; a second block 420 of thermally decomposing the hydrocarbon feed in a fluidized bed of catalyst particles disposed in the reactor chamber to produce an effluent stream comprising hydrogen gas and spent catalyst particles; a third block 430 of removing at least a portion of the spent catalyst particles from the reactor and transferring the spent catalyst particles to a top layer of a multilayer bed disposed in a regenerator; a fourth block 440 of reacting the spent catalyst particles with a counter-current flowing heated gas in the multilayer bed to produce heated regenerated catalyst particles; and a fifth block 350 of returning a portion of the heated regenerated catalyst particles to the reactor chamber. As described above, each layer of the multilayer bed is separated from one another by a grid configured to allow the heated regenerated catalyst particles to travelling downward (by gravity) from the top layer of the multilayer bed to a bottom layer of the multilayer bed. The bottom layer of the multilayer bed is in fluid communication with a conduit which is configured to pneumatically convey at least a portion of the heated regenerated catalystparticles to upper portion of the reactor and into the reactor chamber. The amount of heated regenerated catalyst particles returned to the reactor chamber is an amount sufficient to sustain and in some embodiments initiate (i.e., replace heat generated by initial combustion) the thermal decomposition of the hydrogen feedstock in the reactor chamber.EXAMPLE

[0058] A theoretical calculation was performed for a system according to the present disclosure using the following operating conditions: feed temperatures of hydrocarbon feed (methane) and oxidant (oxygen) to the reactor and regenerator was 900°C; temperature of the reactor was 974°C; methane conversion in the reactor was 98%; methane feed rate to the reactor was 100 mt / hr; catalyst particles were carbon; oxygen feed rate to the regenerator was 89.4 mt / hr; carbon dioxide feed rate to the regenerator was 10.5 t / hr. The results are shown below in Table 1 :Table 1

[0059] Example 2. Simulations were performed using Aspen+ V14 for system 200 presented in FIG 2. In the simulations, the number of grids was varied from 0 to 3 to evaluate the effect and the results are presented below in Table 2. For the simulations, 100 t / h of methane was fed to the fluidized bed reactor and reacted at 963°C and 40 bara on an activated catalyst with a 98% methane conversion. The circulation rate for the heated regenerated catalyst particles was fixed at 1050 t / h and the temperature of the bottom portion of the regenerator was fixed at 1250°C. From the results presented in Table 2, it can be seen that introducing additional grids in the regenerator increased the temperature gradient (difference in temperature between the bottom bed temperature and top bed temperature) over the beds which led to a lower temperature for the top bed. As a result, the required nitrogen flow rate is reduced which may lead to lower equipment size (mainly regeneratorsize) since its diameter can be reduced in order to maintain the proper gas velocity in the multilayer bed (which gas velocity which must be lower than the terminal velocity of the downwardly falling regenerated catalyst particles). A similar effect is expected on the required circulation rate of the heated regenerated catalyst particles if the heating gas circulation rate in the regenerator was fixed (i.e., adding grids would lead to higher temperatures at the bottom of the regenerator and therefore fewer heated regenerated catalyst particles would be needed to be transferred to the fluidized bed reactor in order to maintain the endothermic reaction). A lower circulation rate for the heated regenerated catalyst particles would positively affect energy consumption (energy needed to transfer the heated regenerated catalyst particles to the reactor), equipment wear as well as the rate of attrition of the catalyst particles.Table 2.

[0060] The above specification and examples provide a complete description of the structure and use of exemplary embodiments. Although certain embodiments have been described above with a certain degree of particularity, or with reference to one or more individual embodiments, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the scope of this invention. As such, the various illustrative embodiments of the present devices are not intended to be limited to the particular forms disclosed. Rather, they include all modifications and alternatives falling within the scope of the claims, and embodiments other than the one shown may include some or all of the features of the depicted embodiment. For example, components may be combined as a unitary structure, and / or connections may be substituted. Further, where appropriate, aspects of any of the examples described above may be combined with aspects of any of the other examples described to form further examples havingcomparable or different properties and addressing the same or different problems. Similarly, it will be understood that the benefits and advantages described above may relate to one embodiment or may relate to several embodiments.Embodiments

[0061] Embodiment 1. A system for the production of hydrogen gas from thermal decomposition of a hydrocarbon feed, the system comprising: a) a reactor having an upper portion and a lower portion and a reactor chamber therein; b) a bed of catalyst particles disposed in the reactor chamber; c) a regenerator having an upper portion in fluid communication with the lower portion of the reactor via a first conduit and a lower portion in fluid communication with the upper portion of the reactor via a second conduit and a regeneration chamber therein; and d) a multilayer bed disposed in the regeneration chamber having a top layer, a bottom layer and at least one layer in between, wherein each layer of the bed is separated from one another by a permeable grid; wherein the reactor is configured to receive the hydrocarbon feed and thermally decompose the hydrocarbon feed to produce spent catalyst particles and an effluent stream comprising hydrogen gas; wherein the regenerator is configured to receive an oxidant and at least a portion of the spent catalyst particles from the lower portion of the reactor and react the spent catalyst particles and oxidant to produce heated regenerated catalyst particles and to transfer at least a portion of the heated regenerated catalyst particles to the upper portion of the reactor; wherein the multilayer bed is configured to receive the spent catalyst particles at the top layer of the multilayer bed; wherein each permeable grid is configured to allow the spent catalyst particles to travel downward sequentially from the top layer of the multilayer bed to a bottom layer of the multilayer bed; andwherein heat from the portion of the hot regenerated catalyst returned to the reactor provides at least 70% of energy needed for thermally decomposing the hydrogen feedstock in the reactor chamber.Embodiment 2. The system according to embodiment 1, wherein the reactor comprises a feed inlet configured to receive the hydrogen feedstock at the lower portion of the reactor.Embodiment 3. The system according to embodiments 1 or 2, wherein the regenerator comprises an oxidant feed inlet configured to receive the oxidant at the lower portion of the regenerator,Embodiment 4. The system according to embodiments 1-3, wherein the catalyst particles disposed in the reactor chamber comprise carbon.Embodiment 5. The system according to embodiments 1-4, wherein the reactor is a fluidized bed reactor.Embodiment 6. The system according to embodiments 1-5, wherein the reactor further comprises a reactor outlet conduit configured to receive the effluent stream.Embodiment 7. The system according to embodiment 6, wherein the reactor outlet conduit is in fluid communication with a separator configured to separate hydrogen gas from the effluent stream.Embodiment 7. The system according to embodiments 1-7, wherein the regenerator is a multilayer fluidized bed regenerator.Embodiment 8. A method for thermally decomposing a hydrocarbon feed into hydrogen gas comprising: i) feeding the hydrocarbon feed into a reactor chamber of a reactor; ii) thermally decomposing the hydrocarbon feed in a fluidized bed of catalyst particles disposed in the reactor chamber to produce spent catalyst particles and an effluent stream comprising hydrogen gas;iii) removing at least a portion of the spent catalyst particles from the reactor and transferring the spent catalyst particles to a top layer of a multilayer bed disposed in a regenerator, wherein each layer of the multilayer bed is separated from one another by a permeable grid configured to allow the spent catalyst particles to travel downward from the top layer of the multilayer bed; iv) reacting the spent catalyst particles in the multilayer bed with an oxidant to produce heated regenerated catalyst particles; and v) returning a portion of the heated regenerated catalyst particles to the reactor chamber wherein heat from the portion of the heated regenerated catalyst particles returned to the reactor chamber provides at least 70% of energy necessary for thermally decomposing the hydrogen feed into hydrogen gas in the reactor chamber.Embodiment 10. The method according to embodiment 9, wherein from about 20%-95% by weight of the spent catalyst particles are transferred to the regenerator.Embodiment 11. The method according to embodiments 9-10, wherein the oxidant is bubbled upwards through the multilayer bed.Embodiment 12. The method according to embodiment 11, wherein the oxidant is fed into a bottom portion of the regenerator.Embodiment 13. The method according to embodiment 12, wherein the bubbled oxidant travels upward through the multilayer bed forming a decreasing temperature gradient in the multilayer bed.Embodiment 14. The method according to embodiments 9-13, wherein the hydrocarbon feed comprises natural gas.Embodiment 15. The method according to embodiments 9-14, wherein feeding the hydrocarbon feed into the reactor chamber includes passing the hydrocarbon feed through a distributor positioned at a bottom of the reactor.Embodiment 16. The method according to embodiment 15, wherein the oxidant is introduced into the regenerator by passing the oxidant through a distributor positioned at a bottom of the regenerator.Embodiment 17. A system for the production of hydrogen gas from thermal decomposition of a hydrocarbon feed, the system comprising: a) a reactor having an upper portion and a lower portion and a reactor chamber therein; b) a bed of catalyst particles disposed in the reactor chamber; c) a regenerator having an upper portion in fluid communication with the lower portion of the reactor via a first conduit and a lower portion in fluid communication with the upper portion of the reactor via a second conduit and a regeneration chamber therein; d) a multilayer bed disposed in the regeneration chamber having a top layer, a bottom layer and at least one layer in between, wherein each layer of the bed is separated from one another by a permeable grid; and e) an electrical heating apparatus operable to receive a gas and apply thermal energy to the gas to produce a heated gas wherein the reactor is configured to receive the hydrocarbon feed and thermally decompose the hydrocarbon feed to produce spent catalyst particles and an effluent stream comprising hydrogen gas; wherein the regenerator is configured to receive the heated gas and at least a portion of the spent catalyst particles from the lower portion of the reactor to produce heated regenerated catalyst particles and to transfer at least a portion of the heated regenerated catalyst particles to the upper portion of the reactor; wherein the multilayer bed is configured to receive the spent catalyst particles at the top layer of the multilayer bed;wherein each permeable grid is configured to allow the spent catalyst particles to travel downward sequentially from the top layer of the multilayer bed to a bottom layer of the multilayer bed; and wherein heat from the portion of the hot regenerated catalyst returned to the reactor provides at least 70% of energy needed for thermally decomposing the hydrogen feedstock in the reactor chamber.Embodiment 18. The system according to embodiment 17, wherein the reactor is configured to be initially heated using electrical energy.Embodiment 19. A method for thermally decomposing a hydrocarbon feed into hydrogen gas comprising: i) feeding the hydrocarbon feed into a reactor chamber of a reactor; ii) thermally decomposing the hydrocarbon feed in a fluidized bed of catalyst particles disposed in the reactor chamber to produce spent catalyst particles and an effluent stream comprising hydrogen gas; iii) removing at least a portion of the spent catalyst particles from the reactor and transferring the spent catalyst particles to a top layer of a multilayer bed disposed in a regenerator, wherein each layer of the multilayer bed is separated from one another by a permeable grid configured to allow the spent catalyst particles to travel downward from the top layer of the multilayer bed, iv) reacting the spent catalyst particles in the multilayer bed with a heated gas to produce heated regenerated catalyst particles wherein the heated gas is produced by applying thermal energy to a gas in an electrical heating apparatus; and v) returning a portion of the heated regenerated catalyst particles to the reactor chamber wherein heat from the portion of the heated regenerated catalyst particles returned to the reactor chamber provides at least 70% of energy necessary for thermally decomposing the hydrogen feedstock in the reactor chamber.

[0062] The claims are not intended to include, and should not be interpreted to include, meansplus- or step-plus-function limitations, unless such a limitation is explicitly recited in a given claim using the phrase(s) “means for” or “step for,” respectively.

Claims

CLAIMS1. A system for the production of hydrogen gas from thermal decomposition of a hydrocarbon feed, the system comprising: a) a reactor having an upper portion and a lower portion and a reactor chamber therein; b) a bed of catalyst particles disposed in the reactor chamber comprise one or more of a supported metal catalyst, a carbon-based catalyst or inert material; c) a regenerator having an upper portion in fluid communication with the lower portion of the reactor via a first conduit and a lower portion in fluid communication with the upper portion of the reactor via a second conduit and a regeneration chamber therein; and d) a multilayer bed disposed in the regeneration chamber having a top layer, a bottom layer and at least one layer in between, wherein each layer of the bed is separated from one another by a permeable grid; wherein the reactor is configured to receive the hydrocarbon feed and thermally decompose the hydrocarbon feed to produce spent catalyst particles and an effluent stream comprising hydrogen gas; wherein the regenerator is configured to receive an oxidant and at least a portion of the spent catalyst particles from the lower portion of the reactor and react the spent catalyst particles and oxidant to produce heated regenerated catalyst particles and to transfer at least a portion of the heated regenerated catalyst particles to the upper portion of the reactor; wherein the multilayer bed is configured to receive the spent catalyst particles at the top layer of the multilayer bed; wherein each permeable grid is configured to allow the spent catalyst particles to travel downward sequentially from the top layer of the multilayer bed to a bottom layer of the multilayer bed; and wherein heat from the portion of the hot regenerated catalyst returned to the reactor provides at least 70% of energy needed for thermally decomposing the hydrogen feedstock in the reactor chamber.

2. The system of claim 1, wherein the reactor comprises a feed inlet configured to receive the hydrogen feedstock at the lower portion of the reactor.

3. The system of claims 1-2, wherein the regenerator comprises an oxidant feed inlet configured to receive the oxidant at the lower portion of the regenerator,4. The system of claims 1-3, wherein the catalyst particles disposed in the reactor chamber are carbon.

5. The system of claims 1-4, wherein the reactor is a fluidized bed reactor.

6. The system of claims 1-5, wherein the reactor further comprises a reactor outlet conduit configured to receive the effluent stream.

7. The system of claim 6, wherein the reactor outlet conduit is in fluid communication with a separator configured to separate hydrogen gas from the effluent stream.

8. The system of claim 1, wherein the system further comprises e) an electrical heating apparatus operable to receive a gas and apply thermal energy to the gas to produce a heated gas.

9. The system of claim 8, wherein the reactor is configured to be initially heated using electrical energy.

10. A method for thermally decomposing a hydrocarbon feed into hydrogen gas comprising: i) feeding the hydrocarbon feed into a reactor chamber of a reactor; ii) thermally decomposing the hydrocarbon feed in a fluidized bed of catalyst particles disposed in the reactor chamber to produce spent catalyst particles and an effluent stream comprising hydrogen gas; iii) removing at least a portion of the spent catalyst particles from the reactor and transferring the spent catalyst particles to a top layer of a multilayer bed disposed in a regenerator, wherein each layer of the multilayer bed is separated from one another by a permeable grid configured to allow the spent catalyst particles to travel downward from the top layer of the multilayer bed;iv) reacting the spent catalyst particles in the multilayer bed with an oxidant to produce heated regenerated catalyst particles; and v) returning a portion of the heated regenerated catalyst particles to the reactor chamber wherein heat from the portion of the heated regenerated catalyst particles returned to the reactor chamber provides at least 70% of energy necessary for thermally decomposing the hydrogen feed into hydrogen gas in the reactor chamber.

11. The method of claim 10, wherein from about 20%-95% by weight of the spent catalyst particles are transferred to the regenerator.

12. The method of claims 10-11, wherein the oxidant is bubbled upwards through the multilayer bed.

13. The method of claims 10-12, wherein the hydrocarbon feed comprises natural gas.

14. A system for the production of hydrogen gas from thermal decomposition of a hydrocarbon feed, the system comprising: a) a reactor having an upper portion and a lower portion and a reactor chamber therein; b) a bed of catalyst particles disposed in the reactor chamber; c) a regenerator having an upper portion in fluid communication with the lower portion of the reactor via a first conduit and a lower portion in fluid communication with the upper portion of the reactor via a second conduit and a regeneration chamber therein; d) a multilayer bed disposed in the regeneration chamber having a top layer, a bottom layer and at least one layer in between, wherein each layer of the bed is separated from one another by a permeable grid; and e) an electrical heating apparatus operable to receive a gas and apply thermal energy to the gas to produce a heated gaswherein the reactor is configured to receive the hydrocarbon feed and thermally decompose the hydrocarbon feed to produce spent catalyst particles and an effluent stream comprising hydrogen gas; wherein the regenerator is configured to receive the heated gas and at least a portion of the spent catalyst particles from the lower portion of the reactor to produce heated regenerated catalyst particles and to transfer at least a portion of the heated regenerated catalyst particles to the upper portion of the reactor; wherein the multilayer bed is configured to receive the spent catalyst particles at the top layer of the multilayer bed; wherein each permeable grid is configured to allow the spent catalyst particles to travel downward sequentially from the top layer of the multilayer bed to a bottom layer of the multilayer bed; and wherein heat from the portion of the hot regenerated catalyst returned to the reactor provides at least 70% of energy needed for thermally decomposing the hydrogen feedstock in the reactor chamber.

15. The system of claim 14, wherein the reactor is configured to be initially heated using electrical energy.

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