Reactor with electrically heated structured ceramic catalyst

Abstract

The invention relates to a reactor housing (10) for producing hydrogen and / or synthesis gas and / or carbon dioxide from a feed reaction mixture flow, comprising at least one reaction flow duct (20) formed within the reactor housing (10), at least one structured ceramic catalyst (30) with a plurality of juxtaposed hollow ceramic sub-units (31), at least one electrical heating device (40) for heating the structured ceramic catalyst (30) to a predetermined reaction temperature. The reactor housing (10) is characterized in that the structured ceramic catalyst (30) is electrically heated, wherein the electrical heating device (40) is arranged within at least some of the hollow ceramic sub-units (31) in such a way that the flow passages (313) are still retained.

Description

Technical Field

[0001] This invention relates to a reactor shell for producing hydrogen and / or syngas and / or carbon dioxide from a feed reactive mixture stream, and more particularly to a reactor shell having an electrically heated structured ceramic catalyst. The invention also relates to a method for electrically heating the structured ceramic catalyst using resistance heating. Background Technology

[0002] In all cases where the quantity is insufficient to meet economic conditions, emergency stagnation gas is often used. These releases in remote areas make transportation by truck or pipeline uneconomical. Converting this natural gas into products such as methanol, diesel, gasoline, solvents, and other hydrocarbons presents a necessary opportunity to reduce carbon dioxide (CO2) emissions. All methods for producing these liquids involve a first step in which methane-containing gas is processed into syngas.

[0003] On the other hand, there is a growing need for hydrogen production facilities that convert ammonia, liquid hydrocarbons, and biomass-based products into methanol, ethanol, and biogas or other methane-containing gases. Therefore, in addition to large, centralized plants, there is significant demand for small-scale and distributed hydrogen production, as this will improve and facilitate supply chains that would otherwise rely on large production facilities for the transport of hydrogen as a liquefied or pressurized gas. If this is achieved, widespread use of this fuel in the region will benefit not only fuel cell-based applications but also all other uses where hydrogen can be used as a green fuel and / or reagent and / or feedstock and / or energy carrier.

[0004] In addition to what has been mentioned above, there is a growing need to remove any pollutants from tropospheric ozone levels caused by anthropogenic industrial activities. Environmental regulations in various countries are becoming increasingly stringent regarding VOC emissions, based on the European Union's definition. The necessity to remove VOCs until concentrations are typically below ppm (parts per million) requires not only conventional oxidizing flames or temperatures above auto-ignition, but also catalysts operating at temperatures above 200°C. To achieve an automated, sustainable flame and / or the required reaction temperature, additional fuel is often used, ultimately contributing to increased CO2 emissions. In some applications, electricity has also been used to reach the auto-ignition temperature, as reported in US2014 / 0283812 A1.

[0005] In 2018, more than 70 million tons of hydrogen were produced and used, mainly for ammonia production, refining processes, and methanol production. Different estimates suggest that hydrogen demand will grow rapidly and dramatically over the next 10 years, potentially doubling.

[0006] Currently, over 80% of available H2 is generated through steam reforming (SR) reaction (i), which involves reacting natural gas and / or light naphtha with steam. This reaction is highly endothermic, so approximately 20% of the reacted natural gas is burned in the reformer along with fuel gas produced by pressure swing adsorption (PSA) to maintain the temperature at around 900°C. The remainder is primarily produced through non-catalytic oxidation (PO), which, even when involving exothermic reactions (ii), requires complex and expensive equipment and temperatures above 1200°C.

[0007] CH4 + H2O → CO + 3H2(i)

[0008] CH4 + 1 / 2O2 → CO + 3H2(ii)

[0009] CH4 + CO2 → 2CO + 2H2 (iii)

[0010] Besides SR and PO, a common technology for producing syngas is automated thermal reforming (ATR), which requires large and expensive gas preheating furnaces, pure oxygen, and highly desulfurized reagents. The final product of ATR is syngas, which is mainly used in methanol and Fischer-Tropsch synthesis.

[0011] When only SR and PO are used, and H2 is the desired final product, the resulting syngas undergoes a further water-gas shift reaction (WGS) (iv) in both cases.

[0012] CO + H₂O → CO₂ + H₂ (iv)

[0013] Even though the combustion reformer has an energy efficiency of close to 50%, the overall energy efficiency of the SR process is over 90%, which may be due to the high heat recovery at economies of scale.

[0014] The heat required for the endothermic reaction to compensate for the loss of carbon dioxide is generated by the combustion of methane and other fuels, releasing approximately 3% of global CO2 emissions. The reformer tubes are immersed in a combustion reformer, close to the burner. Inside the reformer tubes, a nickel-based catalyst supported on a ceramic material is used. Due to temperatures exceeding 900°C, the low thermal conductivity of the catalyst, and the strongly endothermic SR reaction, the tube diameter varies from 100 mm to 150 mm to limit the temperature gradient within the reformer tubes. The optimized reformer tube diameter maintains a strong temperature gradient, resulting in a catalyst efficiency factor typically below 10%, requiring hundreds of catalyst-filled reformer tubes ranging in length from 10 m to 13 m. The downstream WGS step involves an exothermic WGS reaction. Depending on the catalyst, the WGS process requires temperatures ranging from 150°C to 400°C.

[0015] Existing technologies for producing hydrogen from liquid reagents and methane-containing gas in a two-step process offer limited flexibility in terms of reagent composition and production capacity. Current processes are capital-intensive, with energy efficiencies below 60% when economies of scale in heat recovery are not feasible. In addition to extra heat exchangers, boilers, reactors, piping, valves, flow meters, fittings, and containers are required. Furthermore, the complexity and custom design of the plant, along with start-up operations, reduces process flexibility.

[0016] To address the aforementioned issues, various attempts have been made. For example, US2013 / 0028815A1 and EP3574991A1 disclose the application of electrified metal catalyst supports. However, insufficient specific surface area and poor support-active phase interactions lead to insufficient catalyst stability. Furthermore, the resulting macrostructures have a considerably large cross-section, reducing resistivity and thus requiring high currents, which complicates the design. For these reasons, no commercially available gas flow heaters utilize charged macrostructures made of metals for temperatures above 600°C. More details on the use of structured metal catalysts for high-temperature reactions can also be found in the article "FeCrAl as a Catalyst Support" by Pauletto Gianluca et al., published in Chemical Reviews 2020, 120, 15, pp. 7516-7550.

[0017] In addition to the above, comprehensive information on syngas production can also be found in the book "Concepts of Syngas Production" by Jens Rostrup Nielsen and Lars J. Christiansen.

[0018] Over the past few years, the cracking of renewable ammonia into hydrogen has emerged as an interesting production pathway for supplying renewable hydrogen. In particular, renewable ammonia is used as an energy carrier, produced in areas with high availability of renewable energy. Here, energy is economically harvested and converted into a chemical substance with high energy density that can be easily transported as a liquid. After transport, the high-value-added renewable ammonia is converted into renewable hydrogen via a catalytic thermochemical process (above 500°C): ammonia cracking. Efficient, compact, corrosion-resistant, and inexpensive modules are needed to convert renewable ammonia into hydrogen for fuel cell applications. In particular, electrified ammonia crackers minimize operating costs because they avoid consuming high-value-added renewable ammonia to generate heat through combustion in inefficient furnaces. Summary of the Invention

[0019] In view of the above-mentioned technical problems encountered in the prior art, one object of the present invention is to reduce investment costs, number of equipment, energy consumption, carbon dioxide emissions, and the size of reactors used for producing hydrogen, syngas, or carbon dioxide.

[0020] Another object of the present invention is to provide a reactor for producing hydrogen, syngas or carbon dioxide, which has greater flexibility in terms of product capacity and the possibility of adding various reactive mixture streams (even containing corresponding amounts of carbon dioxide, sulfides or nitrogen-containing compounds).

[0021] Another object of the present invention is to provide a reactor that uses a resistance heating element for electric heating, which is in direct contact with the reactive mixture vapor and can operate at temperatures above 1000°C, thereby minimizing the temperature difference between the heating element, the structured ceramic catalyst and the reactive mixture stream.

[0022] To achieve the above-described objectives, or those disclosed or inferred from the detailed description, the present invention relates to a reactor shell for producing hydrogen and / or syngas and / or carbon dioxide from a feed reactive mixture stream, the reactor shell comprising:

[0023] At least one reaction flow conduit is formed within the reactor shell and substantially has at least one reaction flow inlet for feeding the reactive mixture, a reaction flow outlet for the reactive mixture exiting the reactor shell, and at least one catalyst section disposed between the reaction flow inlet and the reaction flow outlet.

[0024] Insulating filler, at least partially surrounding the reaction flow conduit,

[0025] At least one structured ceramic catalyst, contained within the catalyst section, and having a plurality of side-by-side hollow ceramic subunits configured to allow a reactive mixture to flow through them.

[0026] At least one resistance heating device, which is meandering and connected to a power source via at least two electrical feeders, is used to heat the structured ceramic catalyst to a predetermined reaction temperature.

[0027] The electric heating device is arranged inside at least some of the hollow ceramic subunits in such a way that a flow channel still exists inside the hollow ceramic subunit.

[0028] In one possible embodiment of the reactor shell, the electric heating device includes a meandering portion that extends in a meandering manner within the structured ceramic catalyst, which is a bundle formed from the hollow ceramic subunits.

[0029] In another possible embodiment of the reactor shell, the ceramic subunit is a ceramic tube.

[0030] In another possible embodiment of the reactor shell, the resistance heating element is preferably a resistance wire.

[0031] In another possible embodiment of the reactor shell, the electric heating device and the power source are configured to heat the structured ceramic catalyst to a temperature between 300°C and 1300°C.

[0032] In another possible embodiment of the reactor shell, the hollow ceramic subunit has longitudinal channels.

[0033] In another possible embodiment of the reactor shell, the reaction flow conduit further includes a preheating / mixing section, a reaction flow channel, and a cooling section. The preheating / mixing section is formed in a continuation of the reaction flow inlet for preheating / mixing the reactive mixture flow. The reaction flow channel connects the preheating / mixing section to the catalyst section. The cooling section is formed in a continuation of the catalyst section for cooling the departing reaction flow before it exits the reaction flow outlet.

[0034] In another possible embodiment of the reactor shell, it has a design pressure between 1 bar and 150 bar.

[0035] The present invention also relates to a method for producing hydrogen and / or syngas and / or carbon dioxide from a feed reactive mixture stream by means of a catalytic reaction in a reactor shell, said catalytic reaction being selected from the group consisting of: ammonia cracking, steam reforming, dry reforming, partial oxidation, reverse water-gas shift, VOC oxidation reaction, and combinations thereof, said reactor shell comprising at least one reaction flow conduit, insulating packing, at least one structured ceramic catalyst, and at least one resistance electric heating device, said reaction flow conduit having at least one reaction flow inlet, a reaction flow outlet, and at least one catalyst section disposed between said reaction flow inlet and said reaction flow outlet, said insulating packing at least partially surrounding said reaction flow conduit, said structured ceramic catalyst being housed in said catalyst section and having a plurality of hollow ceramic sub-units, said hollow ceramic sub-units being configured to allow the reactive mixture to flow through therethrough, said resistance electric heating device being powered by at least two electrical feeds connected to a power source for heating said structured ceramic catalyst to a predetermined reaction temperature. The method includes the following steps:

[0036] The electric heating device is arranged inside at least some of the hollow ceramic sub-units in such a way that the flow channels within the hollow ceramic sub-units still exist.

[0037] By energizing the electric heating device, the structured ceramic catalyst is heated to a temperature between 300°C and 1300°C.

[0038] The reactive mixture, with a pressure between 1 bar and 150 bar, is fed into the reactor shell through the reaction inlet.

[0039] The reactive mixture flow is allowed to pass through the hollow ceramic subunit in such a manner that the reactive mixture flow contacts the electric heating device.

[0040] The reactive mixture stream is allowed to flow out from the reactive stream outlet.

[0041] In a possible application of this method, the electric heating device meanders along the structured ceramic catalyst.

[0042] In another possible application of the method, the reaction stream supplied through the reaction stream inlet is preheated to a temperature of 500°C to 600°C at a pressure of 1 bar to 150 bar, and enters the preheating / mixing section of the reaction stream conduit before reaching the structured ceramic catalyst.

[0043] In another possible application of the method, the reaction stream discharged from the structured ceramic catalyst is cooled to a temperature of 150°C to 800°C in the cooling section of the reaction stream conduit before being discharged from the outlet of the reactive mixture.

[0044] In another possible application of this method, the reactive mixture stream is preheated by the heat from the cooling section via a heat exchange device disposed between the preheating / mixing section and the cooling section or via an additional electric heating device disposed inside or near the preheating / mixing section.

[0045] In another possible application of this method, the reaction type for producing hydrogen and / or syngas and / or carbon dioxide is selected from the group consisting of ammonia cracking, steam reforming, dry reforming, partial oxidation, reverse water-gas shift, VOC oxidation reaction, and combinations thereof.

[0046] Figure Labels

[0047] 10 Reactor shell

[0048] 11 Insulating filler

[0049] 20 Reaction Flow Conduit

[0050] 21 Reactive Mixture Inlet

[0051] 22 Preheating / Mixing Section

[0052] 23 Reaction Flow Channel

[0053] 24 Catalyst Section

[0054] 25 Cooling section

[0055] 26. Reactive mixture outlet

[0056] 30 Structured ceramic catalysts

[0057] 31 Hollow ceramic subunit

[0058] 311 Sub-unit entrance

[0059] 312 Sub-unit Exit

[0060] 313 Flow Channel

[0061] 40 Electric heating device

[0062] 41. Winding section

[0063] 50 power supply

[0064] 51 Electric feeder

[0065] 60 Heat exchange device Attached Figure Description

[0066] Figure 1 The vertical cross-section of the reactor shell is shown.

[0067] Figure 2 The horizontal cross-section of the reactor shell is shown.

[0068] Figure 3 The cross-sectional and vertical sections of the structured ceramic catalyst used in the reactor shell are shown.

[0069] Figure 4 An alternative embodiment of the reaction flow conduit formed in the reactor shell is shown. Detailed Implementation

[0070] Preferred embodiments of the invention will now be described in more detail by way of non-limiting examples with reference to the accompanying drawings.

[0071] exist Figure 1The image shows a reactor shell (10) for producing hydrogen and / or syngas and / or carbon dioxide from a feed reaction stream (i.e., a reactive mixture stream). The reactor shell (10), having insulating packing (11), mainly comprises a reactive mixture conduit (20) and a structured ceramic catalyst (30). The reactive mixture conduit (20) is formed within the reactor shell to be surrounded by the insulating packing (11). The structured ceramic catalyst (30) is formed from a plurality of parallel hollow ceramic sub-units (31) arranged within the reactive mixture conduit (20) to achieve ammonia cracking and / or steam reforming and / or dry reforming and / or partial oxidation and / or reverse water-gas shift and / or VOC oxidation within the reactor shell. The structured ceramic catalyst (30) is a bundle of juxtaposed hollow ceramic subunits (31), each subunit (31) equipped with an electric heating device (40) powered by at least two electrical feeders (51) that pass through the reactor shell (10) insulated from it. These feeders (51) are connected to a power source (50), preferably located outside the reactor shell (10), and configured to heat the structured ceramic catalyst (30) to a desired temperature for the intended reaction. Due to this arrangement, a reactive mixture stream flows through a reactive mixture conduit (20) and is discharged therefrom after being reacted by the structured ceramic catalyst (30). Structural and process details will be described in detail below.

[0072] The reaction flow conduit (20) includes, in downstream order, a reaction flow inlet (21), a preheating / mixing section (22), a reaction flow channel (23), a catalyst section (24), a cooling section (25), and a reaction flow outlet (26). The structured ceramic catalyst (30) is arranged within the catalyst section (24). On the other hand, as Figure 1 As shown, in a preferred embodiment of the invention, a heat exchange device (60) is provided between the preheating / mixing section (22) and the cooling section (25) to adequately transfer the heat of the reactive mixture stream leaving the cooling section (25) to the preheating / mixing section (22). The structural details of the reactive stream, such as its cross-section, dimensions, or path of travel, may vary depending on the design requirements of the specific application. For example, as... Figure 4 As shown, the reaction flow conduit (20) may include four independent reaction flow inlets.

[0073] refer to Figure 1 and Figure 2The structured ceramic catalyst (30) is a “structured catalytic bed” formed by multiple parallel hollow ceramic subunits (31) that form a bundle where the reaction occurs. Each hollow ceramic subunit (31) of the structured ceramic catalyst (30) has a flow channel (313) that allows the reactive mixture to flow through. The structured ceramic catalyst (30) can be formed from multiple tubes, particles, foams, monoliths, or other hollow ceramic shapes that form a bundle in parallel. Therefore, the formation and deployment of the hollow ceramic subunits (31) define the structure of the structured ceramic catalyst (30). The material of the hollow ceramic subunits (31) is selected from the group consisting of SiO2, Al2O3, Y2O3, WO3, ZrO2, TiO2, MgO, CaO, CeO2, FeO2, ZnO2, and combinations thereof, which supports catalytically active materials such as Pt, Ru, Rh, Ir, Pd, or Ni. In addition, in alternative embodiments, the reactor shell (10) may include more than one structured ceramic catalyst connected in series or in parallel and / or having the same or different specifications.

[0074] In the various ceramic catalysts (30) with different structures that can be used to operate under these reaction conditions, ceramic materials will be used because metal supports, even if they generally have good thermal properties, may short-circuit the electric heating device (40), resulting in poor and / or uneven heating, thus reducing the lifespan of the electric heating device. The catalytically active material supported on the structured ceramic catalyst (30) is a group IIIB to IB transition metal (d-block element) and / or a combination of two or more active materials that may include alkali metals. The structured ceramic catalyst (30) will undergo heterogeneous catalyst preparation, as is traditionally done for heterogeneous catalyst synthesis, with initial wetting and / or impregnation and / or support washing and coating and / or in-situ synthesis. The arrangement of the structured ceramic catalyst (30) allows the feed reactive mixture stream to have a contact time of 0.1 ms to 30,000 ms. In this context, the contact time is obtained by dividing the volume of the structured ceramic catalyst by the volumetric flow rate of the reaction stream.

[0075] like Figure 2 and Figure 3As shown, the electric heating device (40) of the present invention is arranged within a hollow ceramic subunit (31) to heat the structured ceramic catalyst (30) from the inside. Specifically, in a preferred embodiment of the invention, the electric heating device (40) meanders through some or all of the plurality of hollow ceramic subunits (31). Due to this embodiment, the hollow ceramic subunits (31) are heated by the electric heating device (40), thereby heating the structured ceramic catalyst (30) from the inside. The physical proximity (or contact) of the electric heating device (40) with the structured ceramic catalyst (30) and the direct contact with the reactive mixture flow enhances heat transfer by radiation, convection, and conduction. This proximity will enable the structured ceramic catalyst (30) to operate at temperatures ranging from 300°C to 1300°C. Relatedly, the combination of the structured ceramic catalyst (30) and the electric heating device (40) must be arranged in such a way that pressure drop is minimized while maintaining high heat and mass transfer influenced by the dimensions of the flow channel (313). For example, preferably, the electric heating device (40) is sized to leave sufficient flow channels (313) inside the hollow ceramic subunit (31) so that the flow of the reactive mixture is minimized while maintaining proximity to the structured ceramic catalyst (30) (i.e., the inner wall of the hollow ceramic subunit (31)). Therefore, in a preferred embodiment, the electric heating device (40) is a sufficiently flexible resistance wire that meanders after binding the hollow ceramic subunit (31). Since the reactive mixture flow is confined within the small gap formed by the electric heating device (40) and the hollow ceramic subunit (31), the temperature difference between the electric heating device (40) and the heated reactive mixture flow is minimized. This has a direct effect on the radial temperature gradient, and thus a direct effect on the carbon formation potential, which, in the case of a reforming reaction, depends on the temperature of the hot surfaces (electric heating device (40) and structured ceramic catalyst (30)) and the temperature of the reactive mixture flow. The hot surfaces (electric heating device (40) and structured ceramic catalyst (30)) are close to each other, have a high viewing factor, and are in direct contact with the reactive mixture flow.

[0076] The resistance of the electric heating device (40) is achieved by using a minimal number of wires that meander within a structured ceramic catalyst (30), which is formed as a bundle of hollow ceramic subunits (31). The electric heating device (40) is a resistance heating wire with a fairly large diameter, preferably greater than 2 mm, thus enabling it to operate at temperatures above 1000°C. According to Ohm's second law, the resistance of the heating device (40) is achieved using long, meandering wires rather than short, small-diameter wires or filaments.

[0077] Since the electric heating element (40) is arranged within the hollow structured ceramic catalyst (30), the resistance heating wire benefits from the mechanical support and geometric constraint provided by the hollow ceramic subunit (31). Due to this configuration, the maximum power of the electric heating element (40) is significantly increased compared to any other device disclosed, due to the very high stability of the longitudinally shaped resistance heating wire, and especially due to the presence of the catalytic material. Surface loading is not limited by electromagnetic forces, thermal expansion, or the lower physical properties caused by extremely high operating temperatures below 1300°C.

[0078] If the electric heating device (40) is embedded in the body of the structured ceramic catalyst (30), the high operating temperature, typically above 1000°C, will cause mechanical stress due to the mismatch between the thermal expansion coefficients of the electric heating device 40 and the structured ceramic catalyst (30). As a result, the ceramic-supported catalyst (30) will crack and fail.

[0079] Furthermore, since the electric heating device (40) meanders through some or all of the multiple hollow ceramic sub-units (31), there is no need to use connector elements to connect the electric heating devices (40) to each other, which will result in: non-uniformity and irregularity of the electric heating devices (40), especially near-potential welding, reduced resistance due to the parallel connection of multiple electric heating devices (40), reduced additional workload and reduced manufacturing complexity.

[0080] On the other hand, the deployment of the electric heating device (40) within the structured ceramic catalyst (30) depends on the selected type and geometry of the hollow ceramic subunit (31), such as tube, particle, foam, monolithic or other hollow ceramic shapes.

[0081] For example, such as Figure 3As shown, the structured ceramic catalyst is a bundle of parallel hollow ceramic tubes forming a grid-like cross-section. Due to this parallel arrangement, the flow of the reactive mixture is confined within the flow channel (313) where the electric heating device (40) is located. If the hollow ceramic sub-units (31) are bundled in a non-parallel manner, bypassing may occur in the area left between adjacent hollow ceramic sub-units (32). Since the bypass area is outside the flow channel (313), it does not directly contact the inner surfaces of the electric heating device (40) and the hollow ceramic sub-units (31), resulting in a decrease in the temperature of the reactive mixture flow and a decrease in reactor efficiency. Therefore, if an integral structured ceramic catalyst is formed in the reactor shell (10), the electric heating device (40) is placed longitudinally inside the hollow ceramic sub-units (31), extending parallel to the flow direction of the reactive mixture flow, while the meandering portion (41) of the electric heating device (20) remains outside the hollow ceramic sub-units (31). After the hollow ceramic subunits (31) are bundled using the installed electric heating device (40), the resistance wire is inserted from the subunit inlet (311) of the first hollow ceramic subunit (31) and led out from the subunit outlet (312) at its other end, then inserted into the subunit outlet of the second hollow ceramic subunit (31) and led out from its subunit inlet, as shown. Figure 1 , Figure 2 and Figure 3 As shown.

[0082] If a foam-type, i.e., open-cell type, is chosen as the hollow ceramic subunit (31) for the structured ceramic catalyst, the electric heating device (40) can extend omnidirectionally similarly to the hollow ceramic subunit (31) defined by the foam structure. Specifically, the electric heating device (40) extends from the inlet to the outlet of the structured ceramic catalyst (30) through the open unit defining the flow channel (313), thereby forming a heating channel along the arrangement of the electric heating device (40). In this case, due to the omnidirectional open structure of the open-cell foam of the structured ceramic catalyst (30), the reactive mixture flows omnidirectionally. The meandering of the electric heating device is carried out in a manner similar to that of the aforementioned embodiment.

[0083] Preferably, the electric heating device (40) comprises a resistance heating element in the form of an electric wire. Due to the size and geometry of the wire and its proximity to the catalytically active material, it can withstand temperatures up to 1400°C, but can also be meandering.

[0084] In view of the above-described structural properties of the present invention, the reaction process will be explained in detail below.

[0085] Once the reactive mixture stream passes through the reactive stream inlet (21), one or more liquid reagent streams consisting of one or more of the following reagents are vaporized and / or atomized / atomized: ammonia, naphtha, alcohol, water, other refined products, methane-containing streams, VOC-containing gaseous streams, and oxidizing streams. The feed liquid and / or gaseous reagents (i.e., the reactive mixture stream) may be atomized and / or vaporized using steam and / or gaseous streams, wherein steam and / or air and / or oxygen and / or carbon dioxide oxidizing streams are also fed. The reactive mixture stream fed to the reactive mixture inlet (21) may be preheated at a temperature below its boiling point, so that evaporation within the reactor shell will be used to cool the reaction products and help control the temperature. The temperature range of the reactive mixture stream fed into the reactive mixture inlet (21) is from 25°C to 600°C, preferably below 200°C, and the pressure range is from 1 bar to 150 bar, preferably below 50 bar.

[0086] The vaporization and / or atomization / spraying (e.g., by ultrasound) that the reactive mixture undergoes before being fed into the reactive stream inlet (21) must ensure optimal phase change of the liquid stream and avoid gas-phase reactions. Evaporation and poor mixing must be avoided because:

[0087] -They may lead to the formation of carbonaceous deposits.

[0088] - These can generate cold spots and / or hot spots, which may damage the reactor shell, including the structured ceramic catalyst.

[0089] - These may create flammable bags inside the reactor shell and could pose safety concerns.

[0090] -They may reduce the yield of the desired product in the reaction.

[0091] - They may require additional and extra energy consumption in structured ceramic catalysts (30).

[0092] In various reactor implementations, the feed of the reactive mixture in liquid form can occur at one or more points and / or locations within the equipment. This is achieved by optimizing the design and / or using the geometry of the reactive flow conduit (20) with high thermal performance (thermal conductivity greater than 10 W / m²). -1 ℃ -1 High surface area materials can improve expansion and atomization.

[0093] In the preheating / mixing section (22), the feed reactive mixture stream is preheated and mixed from the end of the reaction stream inlet (21) to the inlet of the reaction stream channel (23). In this section, the reactive mixture stream from the reaction stream inlet (21) in the form of atomization, vaporization or atomization is heated at a temperature of 50°C to 600°C and a pressure of 1 bar to 150 bar to form a possible two-phase liquid-gas reactive mixture and mix it.

[0094] In a preferred embodiment, an additional electric heating device is provided in the preheating / mixing section (22) for heating the reaction stream.

[0095] In another preferred embodiment, heat in the cooling section (25) is transferred to the preheating / mixing section (22) via a heat exchange device (60) disposed between the preheating / mixing section (22) and the cooling section (25). For example, an additional exothermic reaction (e.g., WGS) occurring at the reactive mixture outlet (26) provides additional heating at a temperature of 150°C to 400°C, wherein the heat is transferred to the preheating / mixing section (22) via the heat exchange device (60), for example, a heat-conducting wall disposed between the preheating / mixing section (22) and the reactive mixture outlet (26).

[0096] In the preheating / mixing section (22), the reactive mixture stream is also homogenized by mixing before entering the reaction flow channel (23). The purpose of the mixing function is to homogenize the reactive mixture stream and increase the temperature before it enters the structured ceramic catalyst (30).

[0097] The preheating / mixing section (22) can have all sorts of different geometries, including hemispherical and parabolic. This area can be empty and / or filled with solids to form a random or structured matrix, thereby improving mixing and heat transfer and reducing size. Therefore, depending on the design of this section, transport phenomena may vary. The design of the preheating / mixing section (22) must also avoid the presence of cold surfaces, which could lead to the deposition of liquid reagents and / or affect the mechanical stability of the reactor and poor cooling of the heat flow in the potential water-vapor shift equilibrium. Furthermore, given the composition, temperature, and pressure, the linear velocity of the reactive mixture flow must be higher than the flame velocity when the feed reactive mixture flow is within the flammability limit.

[0098] Subsequently, the preheated and mixed reactant stream enters the reaction flow channel (23), where minimal heat transfer occurs due to the insulating packing (11) covering the channel. The reactive mixture then flows into the structured ceramic catalyst (30) disposed within the catalyst section (24). In the structured ceramic catalyst, the reactive mixture stream undergoes catalytic reactions, such as ammonia cracking and / or SR and / or DR and / or PO and / or anti-WGS and / or VOC oxidation, through physical contact with the walls of the hollow ceramic subunits (31) supporting the catalytically active material of the structured ceramic catalyst (30). The hollow ceramic subunits (31) are configured to prevent any flow bypass. In other words, the entire reactive mixture stream flowing through the structured ceramic catalyst (30) flows through multiple flow channels (313), directly contacting the electrically heated device (40) and the catalytically active material. The catalytic reaction is achieved when the structured ceramic catalyst (30) is heated from 300°C to 1300°C.

[0099] As described above, the structured ceramic catalyst (30) is heated in an efficient manner by providing the required heat through some or all of the meandering electric heating devices (40) within the hollow ceramic subunit (31). Due to this arrangement, the reactive mixture flowing through the structured ceramic catalyst (30) not only experiences a temperature increase but also reacts on the surface of the structured ceramic catalyst (30) which is effectively and uniformly heated, minimizing any temperature gradients that could lead to carbonaceous deposits and / or thermal effects on the reaction and / or low catalyst efficiency factors. Furthermore, the temperatures reached within the structured ceramic catalyst (30) (typically above 1000°C) will increase the reaction rate, which necessitates reduced contact time, resulting in compact and small reactors.

[0100] The final reaction products will include a mixture of hydrogen and / or syngas and / or CO2, depending on the feed composition and the reactions that occur. At the end of ammonia cracking and / or SR and / or DR and / or PO and / or reverse WGS and / or complete oxidation, the temperature of the reactive mixture is between 300°C and 1300°C, preferably about 1000°C.

[0101] As described above, a further advantage of equipping the structured ceramic catalyst (30) with a meandering electric heating device (40) in the manner of the present invention is as follows:

[0102] - Limit the possibility of secondary reactions

[0103] - Quick Start

[0104] -Prevents in-situ heat generation caused by high-temperature and / or cross-surface heat transfer between different environments and / or flames.

[0105] - The possibility of using endothermic reactions as energy absorbers to increase the lifespan of resistance heating elements and maintain low surface temperatures in resistance heating elements.

[0106] - The possibility of using a meandering electric heating device (40) made of resistance wire, which can operate at a temperature of 1300°C in a structured ceramic catalyst bound together by hollow ceramic subunits.

[0107] - To avoid the possibility of connector elements used for the resistance wire, which would require soldering or other connections, these connections would cause localized non-uniformity in the electric heating device (40), resulting in localized hot spots and causing the electric heating device (40) to fail.

[0108] - The possibility of easily increasing the power duty cycle based on the differences in the composition of the feed reactive mixture stream.

[0109] Strict temperature control will also facilitate and compensate for potential changes in equipment capacity.

[0110] The fact that the resistance of the electric heating device (40) used requires standard operating voltage and current is now used in resistance heaters, avoiding the complex electrical delivery systems required in the case of charged macrostructures of conductive materials, such as in the case of NiCr or FeCrAl alloys or SiC.

[0111] - The possibility of uniformly reaching high temperatures within the structured ceramic catalyst (30) reduces energy consumption because the possibility of having cold and / or hot surfaces is minimized, thereby reducing the amount of oxidative co-reactants required to prevent any catalyst deactivation (e.g., by carbon deposition).

[0112] - The possibility of maximizing product selectivity after minimizing the amount of oxidative co-reactants present during the reforming reaction.

[0113] - The possibility of increasing the operating temperature to convert reagents in endothermic reactions, without being limited by the maximum operating temperature of the surface providing physical constraints, such as in the case of a reformer located in a combustion chamber.

[0114] -The possibility of carbon formation is minimized due to the minimization of the radial temperature gradient within the structured ceramic catalyst (30).

[0115] - The possibility of reaching a temperature of 1400°C under cyclic conditions can be used for catalyst activation and / or regeneration from possible carbonaceous deposits and / or poisoning substances such as sulfur and / or extremely high-boiling-point compounds.

[0116] The reactive mixture stream exiting the structured ceramic catalyst (30) disposed in the catalyst section (24) is cooled in the cooling section (25), where, as described above, it exchanges heat with the catalyst through the wall between the preheating / mixing section (22). This section is used to facilitate heat exchange between the reactive mixture stream exiting the catalyst section (24) and the reactive mixture stream present in the preheating / mixing section (22). This section will involve gas and / or gas-liquid transformation, possibly involving a phase change, thereby maximizing the amount of heat that can be removed. The gas phase exiting the catalyst section (24) and entering the cooling section (25) flows in a region that can have any geometry / configuration and may contain highly conductive structured or / or randomly packed materials that enhance turbulence and / or radial thermal conductivity at the heat transfer interface. The rapid cooling step, relying on the high heat transfer and strong temperature gradient from the boiling liquid, will minimize the cooling time, thereby avoiding any undesirable reactions such as methanation and carbon monoxide dismutation.

[0117] In a preferred embodiment, gas quenching with water or steam can also be used to further cool the reactive mixture stream exiting the catalyst section (24). Countercurrent heat exchange occurring between the preheating / mixing section (22) and the cooling section (25) will improve heat transfer. Energy transfer between the product stream and the reaction stream will occur in the same equipment, thereby enhancing the process and reducing capital investment costs by avoiding additional heat exchangers, piping, valves, flow meters, fittings, and containers. In a preferred embodiment, after the temperature reduction within the cooling section (25), an additional heating aid can be provided to the preheating / mixing section (22) using a system capable of promoting the exothermic WGS reaction at temperatures from 150°C to 400°C.

[0118] Finally, the reactive mixture stream reaches the reaction stream outlet (26) before leaving the reactor shell (10).

[0119] The following results can be obtained through the above-described systems and processes for ammonia cracking and / or SR and / or DR and / or PO and / or reverse WGS and / or VOC oxidation reactions:

[0120] - Completely removes CO2 produced by the combustion of fuel gas required for the high-temperature endothermic reaction.

[0121] - The possibility of relying on renewable electrical energy and converting it into an energy carrier after a thermochemical reaction.

[0122] - High exergy efficiency

[0123] - Avoiding the possibility of temperature gradients would result in low catalyst efficiency coefficients and large reactor volumes.

[0124] - The possibility of converting a wide range of reactive mixtures and producing a wide range of syngas compositions.

[0125] - The possibility of handling and reacting a wide range of reactive mixtures with the primary reaction switching between SR and / or DR and / or PO and / or reverse WGS and / or complete oxidation.

[0126] The possibility of industrializing the -DR reaction, thus enabling the use of CO2 for the final production of syngas and / or hydrogen.

[0127] - Avoid the possibility of expensive high-temperature combustion furnaces and downstream exhaust gas treatment.

[0128] - The possibility of scaling down syngas and / or hydrogen production plants until the current process flow rate is no longer economically feasible.

[0129] Reducing the size and / or number of upstream heat exchangers and / or eliminating the possibility of any preheating not only simplifies the process but also reduces fuel gas consumption, thereby reducing CO2 production.

[0130] - It reduces the likelihood of capital and operating costs, enhances processes, and reduces the size and number of equipment.

[0131] - The possibility of adding air and / or oxygen to the reaction reduces the energy requirement that the electric heating element must supply.

[0132] - The possibility of CO2 presence in the final gas stream in the absence of inert gases (such as nitrogen) and unreacted gases makes low-cost CO2 separation for carbon sequestration possible.

[0133] - The possibility of removing CO2 from the atmosphere using biomass-based reagents, followed by downstream CO2 separation.

[0134] - The possibility of removing VOC impurities without using any additional fuel.

[0135] - Rapid start-up time, flexibility in processing different compositions and reactive mixtures, allowing for rapid changes in syngas and / or hydrogen production, reducing reagent accumulation and storage.

[0136] - The possibility of producing hydrogen and / or syngas using different types of starting reagents decouples process economics from reagent prices assumed during plant design, allowing for switching to the cheapest reagents while using the same methods and equipment.

[0137] - The possibility of using extremely high temperatures (above 1000°C) and high pressures reduces equipment size, further reducing capital costs, heat loss, safety issues, and personnel footprint.

Claims

1. A reactor housing (10) for producing hydrogen and / or synthesis gas and / or carbon dioxide from a feed reactive mixture flow, comprising: at least one reaction flow duct (20) formed within the reactor housing (10) and having at least one reaction flow inlet (21) for feeding the reactive mixture flow, a reaction flow outlet (26) where the reactive mixture flow exits the reactor housing, and at least one catalyst section (24) disposed between the reaction flow inlet (21) and the reaction flow outlet (26), an insulating filler (11) at least partially surrounding the reaction flow duct (20), at least one structured ceramic catalyst (30) housed in the catalyst section (24) and having a plurality of juxtaposed hollow ceramic sub-units (31) configured to allow the passage of the reactive mixture flow therethrough, at least one electrically resistive electric heating device (40) which is serpentine and connected to an electric power source (50) by at least two electric feed lines (51) for heating the structured ceramic catalyst (30) to a predetermined reaction temperature, wherein the electric heating device (40) is arranged inside at least some of the hollow ceramic sub-units (31) in such a way that a flow channel (313) still exists inside the hollow ceramic sub-units (31); the material of the hollow ceramic sub-units (31) is selected from the group consisting of Si02, AI2O3, Y2O3, WO3, Zr02, Ti02, MgO, CaO, Ce02and combinations thereof supporting catalytically active materials selected from the group of transition metals of groups IIIB to IIB and / or combinations of two or more active species including alkali metals; wherein the electric heating device (40) comprises a serpentine portion (41) such that it extends in a serpentine manner within the structured ceramic catalyst (30) which is a bundle formed by the hollow ceramic sub-units (31); wherein the electric heating device (40) passes through the open cells defining the flow channel (313) from the inlet to the outlet of the structured ceramic catalyst (30) thereby forming a heating channel along the arrangement of the electric heating device (40).

2. The reactor housing (10) according to claim 1, wherein the ceramic sub-units are ceramic tubes.

3. The reactor housing (10) according to claim 1, wherein the electrically resistive heating elements are electrically resistive wires.

4. The reactor housing (10) according to the preceding claim 1 or 2, wherein the electric heating device (40) and the electric power source (50) are configured to heat the structured ceramic catalyst (30) to a temperature between 300°C and 1300°C.

5. The reactor housing (10) according to the preceding claim 1 or 2, wherein the hollow ceramic sub-units (31) have a longitudinal channel.

6. The reactor housing (10) according to claim 1, wherein the reaction stream guide (20) further comprises a preheating / mixing section (22), formed in continuation of the reaction stream inlet (21), for preheating / mixing the reactive mixture stream, a reaction stream passage (23) connecting the preheating / mixing section (22) to the catalyst section (24), and a cooling section (25), formed in continuation of the catalyst section (24), for cooling the outgoing reaction stream before leaving the reaction stream outlet (26).

7. Reactor housing (10) according to one of the preceding claims 1 or 2, characterized in that having a design pressure between 1 bar and 150 bar.

8. A method for producing hydrogen and / or syngas and / or carbon dioxide from a feed reactive mixture stream in a reactor housing (10) by a catalytic reaction selected from the group consisting of: ammonia cracking, steam reforming, dry reforming, partial oxidation, reverse water gas shift, VOC oxidation reactions and combinations thereof, the reactor housing (10) comprising at least one reaction stream conduit (20) having at least one reaction stream inlet (21), a reaction stream outlet (26) and at least one catalyst section (24) disposed between the reaction stream inlet (21) and the reaction stream outlet (26), an insulation packing (11) at least partially surrounding the reaction stream conduit (20), at least one structured ceramic catalyst (30) housed in the catalyst section (24) and having a plurality of hollow ceramic sub-units (31) configured to allow the passage of the reactive mixture stream therethrough, The electrically resistive electric heating device (40) is powered by at least two electric feed lines (51) connected to an electric power source (50) for heating the structured ceramic catalyst (30) to a predetermined reaction temperature, and the material of the hollow ceramic sub-units (31) is selected from the group consisting of Si02, AI2O3, Y2O3, WO3, Zr02, Ti02, MgO, CaO, Ce02and combinations thereof supporting catalytically active materials selected from the group of transition metals of groups IIIB to IIB and / or combinations of two or more active species possibly including alkali metals, the electrically resistive electric heating device (40) comprises a meandering section (41) such that it extends in a meandering manner within the structured ceramic catalyst (30) which is a bundle formed of the hollow ceramic sub-units (31); the electric heating device (40) passes from the inlet to the outlet of the structured ceramic catalyst (30) through the open units defining the flow passage (313) forming a heating passage along the arrangement of the electric heating device (40) The method comprises the following steps: arranging the electric heating device (40) inside at least some of the hollow ceramic sub-units (31) in such a way that a flow passage (313) still exists inside the hollow ceramic sub-units, energizing the electric heating device (40) by the electric power source (50) such that the structured ceramic catalyst (30) is heated to a temperature between 300°C and 1300°C, feeding the reactive mixture stream having a pressure between 1 bar and 150 bar into the reactor housing (10) through the reaction stream inlet (21), allowing the reactive mixture stream to pass through the hollow ceramic sub-units (31) in such a way that the reactive mixture stream contacts the electric heating device (40), allowing the reactive mixture stream to flow out from the reaction stream outlet (26).

9. The method according to claim 8, wherein the reaction stream fed through the reaction stream inlet is preheated to a temperature between 50°C and 600°C at a pressure between 1 bar and 150 bar and enters the preheating / mixing section (22) of the reaction stream guide (20) before reaching the structured ceramic catalyst (30).

10. The process according to claim 8, wherein the reaction stream exiting from the structured ceramic catalyst (30) is cooled to a temperature of from 150°C to 800°C in a cooling section (25) of the reaction stream conduit (20) before exiting from the reactive mixture outlet.

11. The process according to claim 9 or 10, wherein the reactive mixture stream is preheated with the heat of the cooling section (25) by means of a heat exchange device (60) arranged between the preheating / mixing section (22) and the cooling section (25) or by means of additional electric heating devices arranged inside or in the vicinity of the preheating / mixing section (22).

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