Process and method for producing hydrogen and carbon from hydrocarbons

Abstract

The present invention provides a system including a pyrolysis reactor containing a particulate bed, a solids heating section, and a separator in fluid communication with the pyrolysis reactor through a product gas outlet. The pyrolysis reactor includes a feed gas inlet below the bed, a product gas outlet above the bed, a particulate outlet above the feed gas inlet, a particulate inlet near the top of the bed, and a solid product outlet below the pyrolysis reactor. The solids heating section is configured to receive a portion of the particulates from the pyrolysis reactor through the particulate outlet, heat the portion of the particulates to form heated particulates, and return the heated particulates to the pyrolysis reactor through the particulate inlet. The separator is configured to separate any particulates in the product gas produced in the pyrolysis reactor and return the particulates to the pyrolysis reactor.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Application No. 63 / 399,057, entitled "PROCESSES AND METHODS FOR PRODUCING HYDROGEN AND CARBON FROM HYDROCARBONS," filed August 18, 2022, which is incorporated by reference herein in its entirety. [Background technology]

[0002] In various chemical processes, gas-phase reactants can produce solid products that must be removed from the reactor without depositing the solid products on the reactor internals. The solid-phase products can be desired products or by-products. For example, preventing carbon deposition (coking) in hydrocarbon reactions is a major concern in many processes. It can also be difficult to apply heat at high temperatures to many hydrocarbon reaction processes without depositing solid carbon on heat transfer surfaces. Summary of the Invention

[0003] In some embodiments, a system for converting hydrocarbon gases into solid carbon and hydrogen products includes a pyrolysis reactor containing a particulate bed, a solids heating section in fluid communication with the particulate outlet and the particulate inlet, and a separator in fluid communication with the pyrolysis reactor through a product gas outlet. The pyrolysis reactor includes a feed gas inlet below the bed, a product gas outlet above the bed, a particulate outlet above the feed gas inlet, a particulate inlet near the top of the bed, and a solid product outlet below the pyrolysis reactor. The solids heating section is configured to receive a portion of the particulates from the pyrolysis reactor through the particulate outlet, heat the portion of the particulates to form heated particulates, and return the heated particulates to the pyrolysis reactor through the particulate inlet, and the separator is configured to separate any particulates in the product gas produced in the pyrolysis reactor and return the particulates to the pyrolysis reactor.

[0004] In some embodiments, a process for converting hydrocarbon gases into solid carbon and hydrogen products includes contacting hydrocarbons in a feed stream with a bed of particulates in a pyrolysis reactor, forming solid carbon on the particulates, forming gas phase products comprising hydrogen, removing a portion of the particulates and the solid carbon product from the pyrolysis reactor, heating a portion of the particulates from the pyrolysis reactor to produce heated particulates in a solid heating section, and returning the heated particulates in the solid heating section from the solid heating section to the pyrolysis reactor.

[0005] In some embodiments, a system for converting hydrocarbon gases into solid carbon and hydrogen products includes a pyrolysis reactor containing a particulate bed and a separator in fluid communication with the pyrolysis reactor through a product gas outlet at an upper portion of the pyrolysis reactor. The pyrolysis reactor includes a feed gas inlet below the bed, a product gas outlet above the bed, a halogen inlet within the bed, and a solid product outlet for particulates having solid carbon at the lower portion of the pyrolysis reactor. The separator is configured to separate any particulates in the product gas produced from the pyrolysis reactor and return the particulates to the pyrolysis reactor.

[0006] In some embodiments, the process for converting hydrocarbon gases to solid carbon and hydrogen products includes introducing a feed stream comprising hydrocarbons into a pyrolysis reactor, introducing an oxidant into the pyrolysis reactor, contacting a first portion of the hydrocarbons with a bed of particulates in the pyrolysis reactor, contacting a second portion of the hydrocarbons with the oxidant in the pyrolysis reactor, forming solid carbon on the particulates, forming gas phase products comprising hydrogen, and reacting the second portion of the hydrocarbons with the oxidant in the pyrolysis reactor. the particulate bed being contacted with an oxidant in a vessel to generate heat, and the heat being used to heat the particulate bed to a pyrolysis reaction temperature.

[0007] These and other features will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings and claims.

[0008] For a more complete understanding of the present disclosure, reference is made to the following brief description taken in conjunction with the accompanying drawings and detailed description. [Brief explanation of the drawings]

[0009] [Figure 1A] FIG. 1A shows a schematic of a tapered spouted bed reactor configuration according to some embodiments. [Figure 1B] FIG. 1B shows a schematic of a tapered spouted bed reactor configuration according to some embodiments. [Figure 2] FIG. 2 shows a schematic of a reactor system using an spouted bed reactor, according to some embodiments. [Figure 3A] FIG. 3A illustrates an exemplary cyclone that may be used within the embodiments disclosed herein. [Figure 3B] FIG. 3B illustrates an exemplary cyclone that may be used within the embodiments disclosed herein. [Figure 4] FIG. 4 shows a schematic of another reactor system using an spouted bed reactor, according to some embodiments. [Figure 5A] FIG. 5A shows a schematic of another reactor system using an spouted bed reactor, according to some embodiments. [Figure 5B] FIG. 5B shows a schematic diagram of another reactor system using an spouted bed reactor, according to some embodiments. [Figure 6A] FIG. 6A illustrates a schematic of a non-mechanical valve useful in a reactor system, according to some embodiments. [Figure 6B] FIG. 6B illustrates a schematic of a non-mechanical valve useful in a reactor system, according to some embodiments. [Figure 7A] FIG. 7A shows a schematic of another reactor system using an spouted bed reactor, according to some embodiments. [Figure 7B] FIG. 7B shows a schematic of another reactor system using an spouted bed reactor, according to some embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0010] In some embodiments, hydrocarbon cracking can be considered a coker with hydrogen as a by-product, since methane cracking produces 3 tons of coke per ton of hydrogen. As used herein, coke refers to solid carbon, which can often be deposited on solid surfaces within a reaction system. Within a coker, carbon can grow on coke particles, for example, in fluid cokers, but it can also grow in other refining and chemical processes. A common observation from these systems is that coke can adhere to existing hot solid surfaces, such as fluid cokers, growing on top of existing hot coke particles. In catalytic cracking, coke tends to grow on the surface of regenerated, high-temperature catalysts. As another example, ethylene crackers form coke on high-temperature furnace tubes.

[0011] Various systems have used solid carbon beds for hydrocarbon pyrolysis. For example, some systems use a countercurrent slow-moving bed of carbon to grow a solid carbon co-product on the downward-moving carbon. Heat can be supplied to the solids in the reactor in the central zone. In some configurations, electrical heating is employed. Other systems use a countercurrent reactor with a series of cascaded fluidized beds circulating carbon from high to low. Other systems use a process with dual fluidized beds, one as a pyrolysis reactor and the other as a carbon solids heater, whereby the carbon is activated to act as a catalyst and the solids can be heated before being returned to the methane pyrolysis reaction.

[0012] Disclosed herein is a hydrocarbon pyrolysis reactor system consisting of a pyrolysis reactor containing solid particles in fluid communication with a separate solid heating vessel, whereby many different methods can be used to heat the solid particles to the pyrolysis reaction temperature and return them to the pyrolysis reactor using valve structures, such as low-impedance valves (e.g., non-mechanical valves) to maintain the pyrolysis reactor at the reaction temperature. Hydrocarbon gases can be introduced into the pyrolysis reactor where they are decomposed into solid carbon and hydrogen. The solid carbon can be preferentially deposited on the solid particles in the pyrolysis reactor, and the gaseous hydrogen product can exit the reactor separately from the solid carbon.

[0013] In some embodiments, the pyrolysis reactor can be an eruptive fluidized bed where a temperature gradient is established within the reactor by introducing a cold hydrocarbon gas into the bottom of the reactor, maintaining the heated particles at a lower temperature (e.g., compared to the reaction zone within the reactor) in the lower and heated regions of the pyrolysis reactor. It can include a riser reactor where hot gas circulates, heating the solids from the reactor and returning the heated solids to the top of the pyrolysis reactor, maintaining them at a higher temperature than the bottom.

[0014] While the disclosed systems and methods are applicable to the production of solid carbon and hydrogen from a variety of hydrocarbons and use a variety of solid particles for carbon deposition, there are several key new components that provide significant advantages over previous systems.

[0015] First, some embodiments use a tapered spouted bed reactor (TSBR) 100. An embodiment of a TSBR is shown in Figures 1A and 1B. As shown, gas can enter through an inlet 102 and a bed 104 filled with solid particles, forming channels 106 that run through the entire solid bed 104. The gas inlet can be designed with a smaller location and cross-sectional area than the bottom of the reactor vessel to allow the incoming gas to form channels 106 through the bed 104. The gas can entrain some of the particles, forming channels 106 and fountains 108 above the channels 106 that can return some of the particles to a particulate-filled annular region 110. The bed 104 can then circulate downward as the particulates on the walls of the channels 106 are entrained and carried to the fountains 108. Product gas can exit through an outlet 112. This configuration can be called an spouted bed, where certain particle characteristics allow a stable gas flow path in which some of the solids move upward with the gas, return to the bed surface, and circulate downward again. The nature of the circulation allows particles of different sizes to layer differently, resulting in selective removal of size ranges. Furthermore, circulation can move hot solids countercurrently inward, contacting the relatively cooler inlet gas, maintaining a vertical temperature gradient. The operation of the spouted bed can be based on specific gas velocities and flow rates to operate at a desired flow regime within the reactor and can be controlled by the reaction system. In some embodiments, the gas flow rate through the spouted bed can be maintained high enough to avoid a bubbling or turbulent flow regime through the particulate bed 104, rather than maintaining a steady channel 106.

[0016] 1B, the TSBR can have a lower inverted frusto-conical portion that holds the particulate bed 104. Above the surface of the particulate bed 104, the TSBR vessel can extend to a height H C The final diameter D C The resulting diameter can be expanded to a height H TThe additional cylindrical cross section above the inverted truncated cone cross section can serve to allow any entrained particulates to settle back into the particulate bed 104. In this design, high gas velocities can be maintained in the channel 106. The high gas velocity can be maintained through the channel up to the top surface of the particulate bed 104. The high gas velocity can entrain some of the particulates, forming fountains 108. The gas velocity above the top surface of the particulate bed 104 can then slow as the cross-sectional flow area increases to the top of the inverted cone section. This allows any entrained particulates to settle out of the gas phase and return to the particulate bed, typically following the interior of the inverted cone cross section and back to the outer portion of the particulate bed. The particulates can then circulate back through the bed to the channel wall.

[0017] In some embodiments, any entrained particulates in the gas stream can be separated from the gas stream and returned to bed 104. For example, as described in more detail herein, one or more external cyclones can be utilized to return the particles to the solids bed. In some embodiments, an internal cyclone within the reactor can be used to separate at least a portion of the particulates for return to the bed. For example, gas exiting the reactor vessel can be passed through a cyclone section to separate the particulates onto the outer wall of the reactor vessel, where they can fall to the top of the bed.

[0018] When used for hydrocarbon pyrolysis, solid carbon can be produced from hydrocarbons passing through inlet 102 in a heated bed packed with solid particles (e.g., sand, solid carbon, catalyst, etc.), with the reaction occurring primarily where the temperature is highest. As described herein, in some embodiments, this can be in the central channel closest to the inlet for the returned heated solids 234. As there is gas diffusion / permeation into the solid bed, additional carbon deposition occurs on the particles forming the walls of the solid bed, causing bed and particle size growth. When the bed is tightly packed, there is little bulk flow away from the central cavity relative to the flow in the main channel.

[0019] The use of the TSBR100 allows for high hydrocarbon gas velocities and gas throughput without slugging or high entrainment of particulates within the separator. This design contrasts with moving-bed reactor designs, which cannot operate at high gas velocities. Multi-tray fluidized beds also cannot operate at high gas velocities due to the tendency of such beds to flood at high velocities. Other designs with straight vertical walls are subject to slugging.

[0020] In the TSBR 100, gas residence times can be relatively short, while the solid carbon product has a longer residence time, allowing for carbon growth and removal (cracking) of polyaromatic by-products. Within the TSBR's eruptions or fountains, entrained hot carbon particles above the erupted bed (e.g., in the eruptor 108) can provide additional hydrocarbon conversion. Carbon can be preferentially deposited on the entrained hot carbon particles. This can help reduce or eliminate coking on the vessel walls above the bed. Additionally, the particulates in the annular region 110 can help insulate the reactor walls, thereby allowing the walls to be constructed of lower-cost materials.

[0021] As explained in more detail herein, some of the fine particles formed in the reaction, including some amount of solid carbon, may exit with the gas stream. However, fine particle entrainment from a tapered spouted bed to a downstream separation system, such as a downstream cyclone system, may be low due to the reactor's expansion in the dilute phase above the top of the bed, which slows the gas as it travels upward. Most entrained fine particles fall to the surroundings around the spouted bed.

[0022] FIG. 2 illustrates an embodiment incorporating a reaction system 200 including a TSBR 100 integrated with a heater section and an external cyclone for solid and gas separation. As shown, a feed gas stream 102 can be introduced into the bottom of the TSBR 100. The TSBR 100 can be the same as or similar to the TSBR 100 described with respect to FIGS. 1A and 1B. The feed gas can include any suitable hydrocarbon, including, but not limited to, light alkanes such as methane, ethane, natural gas, alkenes, alcohols, and other gaseous and solid hydrocarbons, including those that can be gasified, such as pyrolysis products of gasification or liquids (e.g., crude oil, biomass, naphtha, etc.).

[0023] As the gases react within the TSBR 100, hydrogen and solid carbon can be formed within the TSBR 100, with solid carbon products preferentially formed on the solid particulates. The product gas can contain hydrogen and some amount of unreacted hydrocarbons from the feed. The product gas passes through the gas outlet 112 and can be transferred to a separator, such as cyclone 202. Cyclone 202 and other cyclones in the system are described in more detail herein. Within cyclone 202, the gas-phase product can be separated from any entrained solids, such as sold carbon and / or solid particulates, using centrifugal force. The temperature within cyclone 202 can be sufficiently high (e.g., above about 1100°C) to further pyrolyze at least a portion of the remaining hydrocarbons in the gas phase and form carbon on the hot entrained particulates. In some embodiments, cyclone 202 can be operated as a high-temperature external cyclone system with a cold-wall design. The cyclone 202 may be operated at a temperature suitable for converting any residual hydrocarbons, if any, in the gas, or at a lower temperature to further cool the product gas for heat recovery purposes. Solids separated from the gas stream may pass through a solids charger 206 through a solids outlet 204, while the vapor phase product may exit through a top outlet 210.

[0024] In some embodiments, an additional stream 209 of cooled gas can be combined with the vapor-phase product to cool the product gas by direct contact. The cooled gas can be combined with the product gas stream downstream of any secondary cyclone, such as cyclone 212. Once the particulates have been removed, the cooled gas stream can be used to more easily cool the product gas. In some embodiments, the cooled gas in stream 209 can be a cooled portion of the product gas. The product gas can be cooled to a desired level, which in some embodiments can be sufficient to allow further processing of the product gas stream.

[0025] System 200 can include one or more optional secondary cyclones arranged in parallel and / or series to further remove entrained solids from the gas phase product. For example, secondary cyclone 212 can be used to further remove entrained solids from the gas phase discharged from cyclone 202. Any solids removed from the gas phase can be returned to the outlet of cyclone 202 and / or charger 206 and combined with the solids from cyclone 202. While only one secondary cyclone 212 is shown in FIG. 2, any number of additional secondary cyclones can be used in a series and / or parallel configuration to provide a product gas having a desired solids concentration. For example, from one to about eight secondary cyclones can be coupled to cyclone 202 to further separate any solids from the gas phase. The outlet of the second cyclone can be coupled to the outlet of cyclone 202 upstream of TSBR 100 to limit the number of connections and control components required for the solids returning to TSBR 100.

[0026] In some embodiments, the gas passing through cyclone 202 may be cooled before passing through system 200. To cool the product gas passing through cyclone 202, the gas can be contacted with a cooling gas and / or a reaction can be used to cool the gas. In some embodiments, the cooled gas can be combined with the product gas stream upstream of and / or within cyclone 202. For example, the cooled hydrogen product stream can be recycled to cyclone 202 to directly cool the product hydrogen stream. In some embodiments, the product gas can be cooled using a reactant that can undergo an endothermic reaction in the product gas and / or cyclone 202. For example, an alkene can be introduced into a cyclone (e.g., a first-stage cyclone with a fluidized bed below) to react with solids in the fluidized bed below the cyclone in an endothermic reaction. The endothermic reaction can then cool the product gas passing through cyclone 202. Any other suitable method of cooling the product gas can also be used.

[0027] Solids removed from the product gas can be collected and returned to the TSBR 100 through a charger 206. Various designs can be used to control the feed rate of solids returned to the TSBR 100. Additionally, heat integration can be used to preheat the solids in the charger 206 before passing them through the hotter zone at the top of the TSBR 100 bed. For example, the preheated hydrocarbon stream 208 can be introduced into the charger 206 and returned to the TSBR 100, with the solids passing through the hotter upper blowout zone of the TSBR.

[0028] The solid carbon product from the TSBR 100 can be circulated to an outlet 216. The solid carbon outlet 216 can be located below the particulate bed, where a lower temperature can be maintained by introducing a countercurrent of relatively low-temperature feed gas to cool the solid carbon product, as described in more detail herein. In some embodiments, the solid carbon product can pass through the outlet 216 at a temperature ranging from about 900°C to about 1200°C, or from about 950°C to about 1100°C. Various techniques, including air transfer, can be used to remove the relatively low-temperature solid carbon from the TSBR 100 to a solid carbon product vessel via a pressure differential between the two vessels. The solid carbon can be further processed or otherwise removed from the system. As described herein, in some embodiments, solid carbon can form on the particulates in the bed. When the particulates are solid carbon particles, the solid product can include pure or nearly pure carbon. When another type of particulate, such as sand or catalyst particles, is used, the solid product can include solid carbon and some amount of particulate matter, which can be removed and / or processed with the solid carbon product.

[0029] System 200 further includes a heater section configured to heat particulates removed from the particulate bed within TSBR 100, thereby allowing the heated particulates to be returned to the top of the bed within TSBR 100 to provide heat for reaction. As shown in FIG. 2, the particulates can pass through particulate outlet 218 and enter transfer section 220 before passing to riser 230 for heating. In some embodiments, riser 230 can be in fluid communication with TSBR 100 through particulate outlet 218 via a non-mechanical valve, such as an L-valve or loop seal (e.g., as described with respect to FIGS. 6A and 6B), and gas can be used to transport solids in the direction of pressure drop. As described in more detail herein, this configuration can allow particulates to be transported from TSBR 100 along transfer section 220 and into riser section 230. In some embodiments, the gas used to transport the particulates can include a hydrocarbon stream 222, such as a preheated methane stream. While shown as methane, other hydrocarbons, including any of those used for feed gases, can also be used as transfer gases.

[0030] The riser 230 can allow the solids to be heated to very high temperatures using combustion or preheated gas (e.g., electrically heated gas, etc.) directly contacting the solids. Alternatively, a loop seal or L-valve may be used as a non-mechanical valve. Use of the riser section 230 in this particular configuration can enable a low-cost means of providing reaction heat to the heated solid particle stream returned to the top of the TSBR 100 using direct combustion of hydrocarbons or hydrogen in an oxygen-containing gas such as air or oxygen, or by electrically heating an injected gas stream (e.g., hydrogen, inert gas, etc.). Additionally, a non-mechanical valve is used to control the cooling carbon particles fed to the riser and oxygen / air separation from the riser. The riser provides a short average reaction time for hydrocarbon combustion, reducing or minimizing solid carbon combustion.

[0031] In some embodiments, heating within the riser section 230 can be achieved by combustion of gases within the riser section to directly heat the particulates within the riser section 230. As shown in FIG. 2, one or more streams of combusted hydrocarbon gases 222, 224 (e.g., hydrocarbons, hydrogen, etc.) can be used to transport the particulates within the riser section 230. Within the riser section 230, an oxygen source can be introduced into stream 226. The oxygen source can include air and / or an oxygen-enriched stream. An oxygen-enriched stream refers to any stream having an oxygen concentration higher than that of atmospheric air. The oxygen stream can be obtained at the desired purity from an oxygen storage tank or via an oxygen-enrichment process, for example, separation of air into nitrogen and oxygen, such as pressure swing adsorption (PSA), vacuum swing adsorption (VSA), or cryogenic separation techniques. The oxygen in the oxygen stream may have at least about 70% by volume, at least 80% by volume, or at least 90% by volume (e.g., 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 99.1, 99.2, 99.3, 99.4, 99.5, 99.6, 99.7, 99.8, 99.9, or 100% by volume oxygen). In some embodiments, hydrogen can be used as the combustion gas instead of hydrocarbons in the riser section 230. This can allow the combustion products to include steam rather than carbon oxides such as carbon dioxide. Although shown as a single stream entering the bottom of the riser section 230, the air and / or oxygen-enriched stream 226 may be introduced as two or more separate streams along the length of the riser section 230. The use of a riser provides flexibility through combustion heating of carbon in the riser. In some embodiments, the air or oxygen enriched in the gas stream is used for combustion in the riser to reach higher temperatures more efficiently, producing either a more purified carbon dioxide stream that is easily sequestered if hydrocarbon combustion is used, or steam if hydrogen combustion is utilized. The use of a riser also provides an elevation and high pressure differential to return the heated particulates to the top of the pyrolysis reactor.

[0032] The hydrocarbons and oxygen can be combusted in the riser section 230 to form combustion product gases and heat. The combustion product gases can include gas-phase products such as carbon monoxide, carbon dioxide, water, and unreacted hydrocarbons. When an oxygen-enriched gas is used, the amount of nitrogen present can be reduced and the concentrations of carbon monoxide, carbon dioxide, and water can be increased. This can allow for a more concentrated carbon dioxide stream exiting the system if carbon dioxide separation is desired. The particulates can be heated in the riser section to temperatures of about 700°C to about 1400°C.

[0033] The product stream from the riser section 230 may pass to a primary cyclone separator 228 to separate the hot particulates from the gas-phase products. The heated particulates may pass through a solids outlet 234 to a location near (e.g., at or above) the top of the particulate bed within the TSBR 100. A preheated hydrogen stream 236 may pass over the particulates in the solids outlet 234 to prevent backflow of oxygen-containing gas into the TSBR 100 and convey the solids through an L-valve. The hydrogen in the hydrogen stream 236 may react with any remaining oxygen and provide a reducing environment to prevent oxygen from entering the TSBR 100. The heated particulates may then enter the top of the TSBR 100 through a non-mechanical valve to carry out the reaction. As shown in FIG. 2, the riser section 230 may then function to elevate and heat the particulates, allowing them to flow back into the TSBR 100 through the non-mechanical valve by gravity and / or pneumatic conveyance. For example, the riser can lift the hot particulates to a high height and provide a means of a strong pressure differential to circulate the hot particulates to the top of the TSBR 100 .

[0034] The vapor-phase products and / or other gases associated with heating the solids in the riser can exit cyclone 228 for further processing and / or heat recovery through gas outlet 232. System 200 can include one or more optional secondary cyclones to further remove entrained solids from the vapor-phase products from the riser section. For example, One or more secondary cyclones 238 can be used to further remove entrained solids from the gas phase exiting cyclone 228. Any solids removed from the gas phase can be returned to the cyclone outlet and combined with the solids in cyclone 228 solids outlet 234. While FIG. 2 shows only one secondary cyclone 238, any number of additional secondary cyclones can be used in series and / or parallel configurations to provide a product gas having a desired solids concentration. For example, from one to about eight secondary cyclones can be coupled to cyclone 228 to further separate any solids from the gas phase. The outlet of the second cyclone can be coupled to the outlet of cyclone 228 upstream of TSBR 100 to limit the number of connections and control components required for the solids returning to TSBR 100.

[0035] The use of cyclones and secondary cyclones offers several advantages. The system utilizes one or more external cyclones to separate and return the riser termination and hot carbon particles, as well as an external secondary cyclone. The primary cyclone captures the majority of the heated solid particulates and provides a means for returning the particles to the reactor for heat addition. The primary cyclone can terminate with a non-mechanical valve for both controlling the carbon particle circulation and isolating oxygen from the hydrocarbons in the reactor. The use of a riser and cyclone system can also be used to start up a reactor system by heating and circulating the solid media, methane, and air / oxygen. For example, the riser section can be operated to heat the particulates in the TSBR 100 before or during the introduction of hydrocarbons into the TSBR 100.

[0036] The external cyclone system can allow for a cold-wall design for the entire heating system, enabling very high-temperature operation using only stable refractory materials in contact with the reactants and heated gases. For example, various elements of the system 200, including those internal to the heat supply system (e.g., riser section 230, cyclone 228, and transfer conduits), can be cold-wall designed. A cold-wall design generally refers to an internal refractory line vessel whose exterior walls are not insulated. This design helps avoid the use of expensive materials while also limiting the possibility of carbon deposition on the walls of the reactor, cyclones, and conduits themselves. Rather, carbon preferentially deposits on high-temperature particulates, avoiding coke buildup on internal process surfaces.

[0037] The reactor system uses a circulation of a high-temperature solid medium in which hydrocarbon pyrolysis occurs. Any suitable solid can be used in the system, such as solid carbon, sand, or catalyst particles. The catalyst particles can include particles containing a catalytic component, such as iron (e.g., iron oxide), nickel, cobalt, or any other suitable catalytic component. In some embodiments, the solid can be carbon. In some embodiments, the solid can be sand or other stable, chemically inert ceramic. In the case of sand, which is primarily composed of silica, the formation of a dense carbon solid can be possible on the sand, rather than a low-density soot like carbon. High-density carbon has improved handling advantages. Furthermore, the material has a high melting temperature that exceeds the required pyrolysis temperature. Sand is also low-cost, and fine particles, including sand, in fluidized-bed reactors have long been used industrially.

[0038] The cyclone used in the system may include any suitable cyclone. Examples include a conventional cyclone separator, a stripper cyclone, or any other cyclone design suitable for separating a gas phase from a solid phase. FIG. 3A illustrates one embodiment of a cyclone design. As shown in FIG. 3A, cyclone 300 may include a vertical cyclone separator 305. Cyclone separator 305 may have an inlet 306 for receiving gas and solid particulates, for example, from a riser in the heater section and / or a gas phase outlet of the TSBR 100. The cyclone further includes an upper tubular portion 308, a conical portion 309, and a dipleg 310. Cyclone housing 305 may further include an upper roof or shoulder 311 through which gas outlet 312 may pass to provide an outlet for the gas phase. Inlet 306 may be positioned to enter cyclone housing 305 tangentially relative to the wall to form a circulation or vortex within cyclone housing 305. The resulting vortex can cause fine particles to fall against the outer wall and downward into dipleg 310 for passage out of the cyclone housing 305. The central gas region of the vortex can then allow the gas phase to pass upward through gas outlet 312. Combining cyclone 305 extensions at shoulder 311 and outlet 312 can help reduce or prevent any solid fine particles from exiting the cyclone with the gas phase. One or more solids passages 302 can be used to return solids from any secondary cyclones to dipleg 310 of cyclone housing 305. While shown at or within dipleg 310, one or more solids passages 302 can be connected to a solids conduit anywhere between the cyclone and the TSBR 100. Any of the secondary cyclones described herein may have a design identical or similar to that of the cyclone housing 305, with the inlet to such secondary cyclone fluidly coupled to the outlet 312 of the cyclone housing 305 and the solids outlet from such secondary cyclone fluidly coupled to the solids passage 302 to return solids to the TSBR 100.

[0039] In some embodiments, any of the cyclones described herein (e.g., cyclone 202, cyclone 228, and / or any secondary cyclones) can include a stripper cyclone. Generally, a stripper cyclone can include a cyclone with a solids inventory within the cyclone, with a stripping gas introduced and passing through the solids within the cyclone, maintaining the solids as a fluidized bed. In some aspects, using a stripper cyclone with sufficient solids inventory (e.g., operating as a miniature fluidized bed) allows for stable control of carbon particle circulation. In this embodiment, fines captured within the secondary cyclone can be maintained as a fines feed that can be controllably sent back to the primary cyclone. This can help maintain a desired fines level within the TSBR 100 and can enable start-up operation. The use of a stripper cyclone also serves as a receiving vessel for returns from the secondary cyclone, simplifying and miniaturizing the cyclone system. The use of a secondary or stripper cyclone can also serve as a receiving vessel for the production of carbon particles and the potential use of sand for energy integration.

[0040] FIG. 3B schematically illustrates a stripper cyclone 350 embodiment. Stripper cyclone 350 is similar to cyclone 300 of FIG. 3A, except that cyclone 350 includes a lower portion 359 of a cyclone housing 358 having a closed lower end 360. A fines outlet 361 extends into cyclone 350 through closed lower end 360. Fines outlet 361 may include a tubular structure with an open upper end within cyclone 350 below inlet 306. Fines outlet 361 has a smaller diameter than the inner wall of cyclone 350 such that an annulus is formed between the outer wall of fines outlet 361 and the inner wall of cyclone 350. Fines outlet 361 also includes one or more openings 364, which may be in the form of vertical or horizontal slots, circular or elliptical openings, or any other suitable shape. The opening 364 may be located between the top of the fines outlet 361 and the closed lower end 360 of the cyclone 350 .

[0041] The vortex finder 370 can be positioned above the top of the particulate outlet 361. The vortex finder can include a horizontal vortex stabilizer or cone and a stabilizer rod to hold the vortex stabilizer in place. The vortex finder 370 serves to reduce the gas velocity below the vortex finder 370 so that the primary separation of solids from the gas phase occurs above the vortex finder 370.

[0042] The stripping section is formed in the lower part of the cyclone 350 below the vortex finder 370. Based on the design of the fine particle outlet 361, a solids inventory can be maintained within the cyclone 350, typically with the upper surface 372 of the solids bed maintained below the upper end of the fine particle outlet 361. One or more gas inlets 366 can be positioned as a gas ring at or near the bottom of the cyclone 350 to provide stripping gas that can also be used to maintain fluidization of the fine particle bed. Gas introduced into the gas inlet 366 can pass upward through the fine particle bed, entering the gas phase and exiting the cyclone 350, with the gas phase entering the cyclone 350 through the inlet 306. The gas flow can be controlled to maintain the fine particle bed in a fluidized state.

[0043] The one or more solids passages 302 may be in fluid communication with one or more secondary cyclones, as described herein. The solids passages 302 may allow solids separated from the gas exiting the cyclone 350 to enter a fine particle bed within the cyclone 350, where the solids may be further stripped and maintained as solid inventory before returning to the TSBR 100.

[0044] In use, gas and solids passing through cyclone 350 can enter the top of cyclone 350 with gas inlet 306 positioned tangentially to the inner wall of cyclone 350. As the gas phase and solids form a vortex, the solid phase can migrate to the outer wall and fall onto a fine particle bed in the lower part of cyclone 350, while the gas phase can exit through outlet 312. Vortex finder 370 can maintain the vortex above vortex finder 370 and reduce the gas velocity in the lower part of cyclone 350 below vortex finder 370. Fine particles falling from the top can then form a fine particle bed in the lower part of cyclone 350.

[0045] Stripping gas can be introduced through gas inlet 366 to fluidize the particulate bed. The fluidized particulates can then pass through the particulate outlet through opening 364. A level controller can be used to control the flow of the fluidizing gas to maintain the level of the particulate bed within cyclone 350.

[0046] In some embodiments, the stripping gas introduced through gas inlet 366 can include an oxidizing gas, such as air or oxygen. The gas entering cyclone 350 may contain some amount of carbon monoxide based on the oxygen-to-hydrocarbon ratio introduced in the heater section. The oxygen introduced through the stripping gas can then be controlled to adjust the level of carbon monoxide in the gas exiting the cyclone through outlet 312. The resulting combustion of the remaining hydrocarbons and / or carbon monoxide can further heat the particulates in the particulate bed, although the primary heat may be generated in the heater section.

[0047] As further shown, the ability to control the fines bed level in stripper cyclone 350 can have the added benefit of maintaining an inventory of fines for use with TSBR 100. Additionally, the use of a stripper cyclone can allow fines to be collected from one or more secondary cyclones and transferred to TSBR 100 from a single location. Thus, in some embodiments, one or more of the cyclones in the systems described herein may be stripper cyclones. When used with product cyclone 202, the use of a stripper cyclone can also allow for heat integration and / or control of the temperature of the carbon based on the use of stripping gas.

[0048] Figure 4 illustrates another embodiment similar or identical to the embodiment of Figure 2. For the sake of brevity, detailed descriptions of similar or identical components will not be repeated. The primary difference between system 200 of Figure 2 and system 400 of Figure 4 is the location of particulate outlet 418 from TSBR 100. As shown in Figure 4, the particulate outlet into transfer conduit 418 is located at the carbon product outlet 2 16. By varying the level at which the particulates are removed for heating, the thermal profile within the TSBR 100 can be controlled. For example, when the particulate outlet is above the carbon product outlet 216, the lower portion of the reactor can be maintained at a lower temperature, resulting in a lower temperature carbon product exiting the reactor. In some embodiments, the temperature at or near the top of the particulate bed within the TSBR 100 can be between about 1400°C and about 1200°C, and the temperature at or near the bottom of the particulate bed (e.g., at or near the carbon product outlet 216) can be between about 800°C and about 1100°C, or between about 950°C and about 1050°C.

[0049] In some embodiments, a thermal profile is shown schematically in FIG. 5A. The embodiment of FIG. 5A can include portions of the system 200 described with respect to FIG. 2 and / or the system 400 described with respect to FIG. 4. In some embodiments, the selective introduction of particulates, such as solid carbon, into the TSBR 100 enables efficient heat accumulation. A unique feature of the disclosed system is the creation of a temperature gradient within the TSBR with the highest temperature at the top of the bed in the blowout region, enabling a reaction that deposits carbon on the blown solids. See FIG. 5A, which has colors that qualitatively correlate to temperature (cooler at the bottom and hotter at the top of the particulate bed). A primary supply of relatively cool hydrocarbon gas can be introduced at the bottom of the TSBR 100, which transfers heat from the surrounding solids to heat the hydrocarbon gas to reaction temperatures as the gas rises, while solid carbon traveling downward within the reactor is cooled and transported to a non-mechanical valve near the bottom, where the solids can be removed as a relatively cool solids stream.

[0050] As shown, the use of a TSBR 100 with high temperature heated particulates (e.g., carbon, sand, etc.) continuously introduced at the top of the bed through stream 234, and low temperature hydrocarbons continuously introduced at the bottom of the bed through stream 102, allows for the maintenance of a steady state temperature gradient from cooling the bottom of the bed with heating of the relatively low temperature hydrocarbon feed. For example, the temperature of the hydrocarbon feed can be controlled to produce a carbon product with a desired outlet temperature, while the velocity and temperature of the particulates introduced from the top via stream 234, as well as their intermediate position through stream 506, can be controlled to produce a desired temperature profile within the TSBR 100.

[0051] The configurations shown herein allow for multiple heat accumulation configurations to retain heat within the system. During operation, the carbon product stream 216 can be continuously removed from the bottom of the bed after being cooled by the incoming hydrocarbon feed passing into the reaction zone. Recovering heat from the cooled solids using a preheated feed provides heat accumulation for hydrocarbon pyrolysis. A hot carbon bed fed at the top of the bed in the TSBR 100 creates a desirable steady-state adiabatic temperature profile with the highest reactor temperature at the top of the bed, which drives the highest hydrocarbon conversion at the reactor gas outlet from the bed (e.g., in the fountain section). As the incoming gas is heated, the bottom of the bed, where the hydrocarbons are introduced, is cooled. The cooled carbon is removed as a co-product at the bottom.

[0052] In this system, the cyclone used to separate the vapor phase product from the TSBR 100 can be operated as a separator 502 with a fluidized bed with an internal cyclone. In this embodiment, the separator 502 can store a portion of the solids separated from the vapor phase product within the separator 502. The vapor phase product from the TSBR 100 can enter the lower portion of the separator 502 in a particulate bed. The hot vapor phase product can then be heat exchanged with the particulates in the fluidized bed within the separator 502. Further reaction (e.g., pyrolysis) of hydrocarbons in the fluidized bed can cool the particulates and gases. Additionally, a cooled carbon product stream 504 can be returned to the fluidized bed separator 502 to cool the vapor phase product. Meanwhile, the particulates can be preheated for use in the TSBR 100. For example, a portion of the cooled solids product stream 216 can be returned to separator 502 as stream 504. The cooled solids can cool the hot gas passing through the fluidized bed in separator 502, and the product gas exiting separator 502 can be cooled and exit the system. In some embodiments, an internal cyclone can be used in separator 502 to separate fine particles in the fluidized bed from the gas stream, thereby helping to retain the particles within separator 502. The partially heated solids can be returned to the TSRB 100 either above or below the hot solids return stream. The location of introduction of stream 506 can be selected to match or provide a desired temperature profile within the TSRB 100 bed. In some embodiments, one or more primary and / or secondary cyclones can be coupled to the outlet of separator 502 as described herein to remove residual fine particles entrained in the cooled product gas. Solids that are heated in the riser to provide heat of reaction are drawn below the bed through outlet 318 and sent to the riser section where they can be heated.

[0053] FIG. 5B illustrates another embodiment similar to the embodiment of FIG. 5A, and similar elements will not be described again for the sake of brevity. The embodiment of FIG. 5B can include portions of system 200 described with respect to FIG. 2 and / or system 400 described with respect to FIG. 4. In this system, cyclone separator 512 used to separate the gas-phase product from any entrained particulates can operate as a cyclone (e.g., a stripper cyclone) as described herein. In this embodiment, cyclone separator 512 can store a portion of the solids separated from the gas-phase product within cyclone separator 512. Gas stream 514 can be returned to the cyclone to serve as a fluidizing gas for the particulates below cyclone separator 512. The fluidizing gas can include a cooled gas for cooling the particulates. In some aspects, the gas can include hydrocarbons (e.g., any of those described herein), and the resulting pyrolysis reaction of the hydrocarbons with the particulates can serve to cool the particulates and product gas passing through cyclone 512. If further cooling is desired, the product gas can be quenched using a cooled gas stream combined with the product gas stream, which can be combined downstream of cyclone separator 512, and / or an optional secondary cyclone coupled to cyclone separator 512. The product gas can exit the system, while the partially heated solids can be returned to the TSBR 100 either above or below the hot solids return stream. The location of introduction of stream 506 can be selected to match or provide a desired temperature profile within the TSBR 100 bed. Solids that are heated in the riser to provide heat of reaction can be withdrawn below the bed through outlet 318 and sent to the riser section where they can be heated.

[0054] In any of the embodiments disclosed herein, one or more non-mechanical valves can be used to control the flow of solids and / or gases within the system. For example, in some embodiments, solids proceeding from the TSBR 100 to the heater section, solids exiting the heater section cyclone, and / or solids exiting the product gas cyclone can each pass through and be controlled by a non-mechanical valve. Due to the high temperatures present in the system, mechanical valves may be unable to operate or may have operational issues over time. In some aspects, non-mechanical valves can allow the movement of solid particles while providing gas isolation. For example, the use of non-mechanical valves for gas isolation on each side of a reactor system with combustion on one side and reduction / dehydrogenation on the other side allows for the separation and control of particle circulation rates and bed levels. Non-mechanical valves also provide a workable method for circulating particles while isolating gases on each side of the reactor where mechanical valves (e.g., sliding valves) cannot withstand high temperatures.

[0055] 6A and 6B show two common non-mechanical valves. FIG. 6A shows an L-valve 600, and FIG. B indicates a loop seal. Such conduits are used to circulate particles through the fluidized bed system, transporting them from low-pressure regions to high-pressure regions, avoiding reverse gas flow and providing effective gas tightness. Such valves can be used to control solids movement, such as withdrawing low-temperature and large carbon particles at the bottom of the TSBR 100. As shown in Figure 6A, the riser section is shown on the left, and the fine particle outlet or standpipe is shown on the right. The valve relies on the pressure differential created by the presence of particles in the standpipe relative to the shorter particle height above the outlet to generate a gas-phase flow capable of carrying the particles. As shown in Figure 5B, fine particles can accumulate in the loop seal standpipe, and when gas is introduced to the left, the particles can be lifted to the recirculation or outlet pipe. The recirculation or outlet pipe may be the riser section in some embodiments and / or one of the other transfer lines described herein (e.g., solid carbon outlet from the TSBR, solids outlet from a cyclone, etc.). As the solid carbon moves to the outlet pipe, the solids in the standpipe can move toward the outlet. Furthermore, the gas phase used to displace the particulates will preferentially flow toward the outlet due to the pressure differential created by the presence of the particulates in the standpipe, so the design can be used as a valve with no mechanically moving elements.

[0056] FIG. 7A shows another embodiment of a reactor system 700 that can rely on reactions within the TSBR 100 to provide the heat needed to crack hydrocarbons. This configuration can advantageously eliminate the need for a riser section, simplifying the overall process. As shown, the oxidant can be introduced as stream 702 to the bottom of the particulate bed, where the oxidant can react with a portion of the hydrocarbons within the TSBR 100 in an amount sufficient to generate heat, eliminating the need for added heat for the cracking reaction (e.g., autothermal or exothermic). Any suitable oxidant can be used, such as a halogen (e.g., chlorine, bromine, etc.), an oxygen-containing gas (e.g., oxygen, etc.), or sulfur. The enrichment is qualitatively related to temperature, with lower temperatures at the bottom of the TSBR 100 and higher temperatures at or near the surface of the particulate bed. A primary feed of relatively cool hydrocarbon gas can be introduced to the bottom of the TSBR 100, transferring heat from surrounding solids to heat the hydrocarbon gas to reaction temperatures as it rises, while cooling the solid carbon moving downward within the reactor to a non-mechanical valve near the bottom. Here, the solid carbon product is removed as relatively cool solids stream 216. A portion of the cooled solids can optionally be returned as stream 504 to the outlet separator, which in this example can be a separator containing a fluidized bed as described herein with respect to Figure 5A, whereby the hot product gases exiting the TSBR 100 can be introduced into cyclone 502, where the gas phase can be cooled and exit, while the partially heated solids can be returned to the TSBR 100 as stream 506, as described in more detail herein.

[0057] FIG. 7B illustrates another embodiment of a reactor system 750 that can rely on reactions within the TSBR 100 to provide the heat needed to crack hydrocarbons. The embodiment of FIG. 7B is similar to the embodiment of FIG. 7A, except that the outlet gas separator can include a stripper cyclone 512. The stripper cyclone can operate in the same or similar manner as the cyclone 512 described with respect to FIG. 5B. As shown, the product gas can pass to the cyclone 512 with a bed or particulates in the lower portion of the cyclone 512, which can receive a fluidizing gas in stream 514, which can include hydrocarbon gases, to cool the particulates through a thermal cracking reaction. The solids can then be returned to the TSBR 100 as stream 506, as described in more detail herein.

[0058] When a halogen is used as the oxidant, it can be recycled within the system by recovering it downstream to produce hydrogen and elemental halogen. When an oxidizer is used, carbon monoxide and / or carbon dioxide may be produced. In some embodiments, the amount of carbon dioxide produced may be low enough to remain in the produced hydrogen stream, or the carbon monoxide and / or carbon dioxide, or any portion thereof, may be removed downstream of the TSBR 100. A primary advantage of using an oxidizer is that it can include the ability to heat the particulate bed within the TSBR 100 itself, rather than relying on external heating of the particulates. This can allow for reaction temperatures within the TSBR 100 to be approximately 1100°C or lower, reducing or eliminating the need to provide other forms of external heat to the TSBR 100. This configuration can also allow for the addition of excess oxidizer to start up the reactor and bring it to steady state.

[0059] Having described various systems, reactors, and methods, particular aspects can include, but are not limited to, the following:

[0060] In a first aspect, a system for converting hydrocarbon gases into solid carbon and hydrogen products includes: a pyrolysis reactor containing a particulate bed, the pyrolysis reactor including a feed gas inlet below the bed, a product gas outlet above the bed, a particulate outlet above the feed gas inlet, a particulate inlet near the top of the bed, and a solid product outlet at a bottom of the pyrolysis reactor; a solid heating section in fluid communication with the particulate outlet and the particulate inlet, the solid heating section configured to receive a portion of the particulates from the pyrolysis reactor through the particulate outlet, heat the portion of the particulates to form heated particulates, and return the heated particulates to the pyrolysis reactor via the particulate inlet; and a separator in fluid communication with the pyrolysis reactor through the product gas outlet, the separator configured to separate any particulates in the product gas produced in the pyrolysis reactor and return the particulates to the pyrolysis reactor.

[0061] A second embodiment may include the system of the first embodiment, wherein the pyrolysis reactor has a tapered lower portion and the particulate bed is disposed in the tapered lower portion.

[0062] A third embodiment can include the system of the second embodiment, wherein the pyrolysis reactor has an upper portion having a larger cross-sectional area than the tapered lower portion.

[0063] A fourth aspect may include the system of any one of the first to third aspects, wherein the particulate bed in the pyrolysis reactor is configured to operate in an spouted bed fluidization regime.

[0064] A fifth embodiment may include the system of any one of the first to fourth embodiments, further including: a first non-mechanical valve disposed at the particulate outlet between the pyrolysis reactor and the solids heating section; and a second non-mechanical valve disposed at the particulate inlet between the solids heating section and the pyrolysis reactor.

[0065] A sixth aspect may include the system of any one of the first to fifth aspects, wherein the separator includes a fluidized bed below the first stage cyclone separator, the fluidized bed configured to receive a portion of the solid product from the first stage cyclone separator and return the solid product to the pyrolysis reactor.

[0066] A seventh aspect may include the system of any one of the first to sixth aspects, wherein the solid-state heating section includes: a riser configured to receive a portion of the particulates from the pyrolysis reactor; a combustion gas inlet for receiving a combustion gas; and an oxygen-containing gas inlet for receiving an oxygen-containing gas, and the solid-state heating section is configured to contact the portion of the particulates with the combustion gas and the oxygen-containing gas, combust the combustion gas to generate combustion product gases, and heat the portion of the particulates to generate heated particulates.

[0067] An eighth aspect is the system of the seventh aspect, wherein the combustion gas is a hydrocarbon-containing gas. It can include.

[0068] A ninth aspect may include the system of the seventh or eighth aspect, wherein the solid heating section further includes a second separator configured to receive the heated particulate downstream portion of the riser and the combustion product gases, the second separator configured to separate and return a portion of the heated particulate to the pyrolysis reactor.

[0069] A tenth aspect can include the system of the ninth aspect, wherein the second separator includes a second fluidized bed below the first stage cyclone, the second fluidized bed configured to receive a portion of the heated particulates from the riser, and a fluidizing gas inlet below the first stage cyclone, the fluidizing gas inlet configured to receive an oxygen-containing gas and further to react the oxygen-containing gas with the combustion product gases within the first stage cyclone.

[0070] An eleventh aspect may include the system of any one of the first to tenth aspects, wherein the separator includes a fluidized bed of particulates; a product gas inlet in fluid communication with the product gas outlet, the product gas inlet configured to pass the product gas through the fluidized bed; and an internal cyclone configured to retain the particulates within the separator.

[0071] A twelfth aspect may include the system of any one of the first to eleventh aspects, further including one or more second stage cyclone separators configured to receive the outlet product gas from the first stage cyclone separator, separate any heated particulates in the outlet product gas, and return the heated particulates to the pyrolysis reactor.

[0072] A thirteenth aspect may include the system of any one of the first to twelfth aspects, wherein one or more of the pyrolysis reactor, the solid state heating section, or the separator has a cold wall design.

[0073] A fourteenth aspect may include the system of any one of the first to thirteenth aspects, wherein the particulate comprises solid carbon, sand, or catalytic material.

[0074] In a fifteenth embodiment, a process for converting hydrocarbon gases to solid carbon and hydrogen products includes contacting hydrocarbons in a feed stream with a bed of particulates in a pyrolysis reactor; forming solid carbon on the particulates; forming gas phase products comprising hydrogen; removing a portion of the particulates and the solid carbon product from the pyrolysis reactor; heating a portion of the particulates from the pyrolysis reactor to produce heated particulates in a solids heating section; and returning the heated particulates from the solids heating section to the pyrolysis reactor.

[0075] A sixteenth aspect can include the process of the fifteenth aspect, wherein removing the portion of the particulates and the solid carbon product from the pyrolysis reactor includes passing the portion of the particulates and the solid carbon product through a non-mechanical valve.

[0076] A seventeenth aspect may include the process of the sixteenth aspect, wherein the non-mechanical valve is an L-valve.

[0077] An eighteenth aspect may include the process of the sixteenth aspect, wherein the non-mechanical valve is a loop seal.

[0078] A nineteenth aspect can include any one of the processes described in the fifteenth to eighteenth aspects, wherein heating a portion of the particulates from the pyrolysis reactor to produce heated particulates includes: contacting a portion of the particulates from the decomposition reactor with a combustion gas and an oxygen-containing gas; combusting the combustion gas to generate heat and combustion product gases; and heating a portion of the particulates with the heat to generate heated particulates;

[0079] A twentieth embodiment may include the process of the nineteenth embodiment, further comprising passing the heated particulates and combustion product gases through a first stage cyclone separator; and separating the heated particulates from the combustion product gases and returning the heated particulates to the pyrolysis reactor.

[0080] A twenty-first embodiment can include the process of the twentieth embodiment, further including passing a reducing gas through the heated particulates downstream of the first stage cyclone separator and upstream of the pyrolysis reactor; and returning the heated particulates to the pyrolysis reactor while reducing oxygen-containing species in the entrained combustion product gases.

[0081] A twenty-second aspect may include any one of the processes described in the nineteenth to twentieth aspects, wherein at least one of the combustion gas or the oxygen-containing gas is entrained by a portion of the particulates from the pyrolysis reactor.

[0082] A twenty-third aspect may include any one of the processes described in the nineteenth to twenty-second aspects, wherein the combustion gas comprises hydrogen.

[0083] A twenty-fourth aspect may include the process of the twenty-second or twenty-third aspect, wherein the combustion gas is a hydrocarbon gas.

[0084] A twenty-fifth aspect may include any one of the processes described in the nineteenth to twenty-fourth aspects, wherein the oxygen-containing gas comprises air or an oxygen-enriched gas.

[0085] A twenty-sixth embodiment can include the process of any one of the fifteenth to twenty-fifth embodiments, further including removing the gas phase products from the pyrolysis reactor; separating fine particles from the gas phase products in a first stage cyclone separator having a fluidized bed therebelow; and returning the separated heated fine particles to the fluidized bed having an outlet therebelow that discharges the heated particles to the pyrolysis reactor.

[0086] A twenty-seventh embodiment can include the process of the twenty-sixth embodiment, wherein separating the particulates from the gas phase product includes: passing the gas phase product through an upper portion of a first stage cyclone separator above the fluidized bed having a gas inlet at a lower portion for introducing a second hydrocarbon gas; cooling the particulates in the fluidized bed via a pyrolysis reaction of the second hydrocarbon gas in the bed and cooling the gas phase product in the fluidized bed; and returning the particulates from the fluidized bed to the pyrolysis reactor.

[0087] A twenty-eighth embodiment may include the process of the twenty-sixth or twenty-seventh embodiment, further including one or more second stage cyclone separators configured to receive the outlet product gas from the first stage cyclone separator, separate any heated particulates in the outlet product gas, and return the heated particulates to the pyrolysis reactor.

[0088] A twenty-ninth embodiment may include the process of the twenty-seventh or twenty-eighth embodiment, further including one or more second stage cyclone separators, the one or more second stage cyclone separators configured to receive cooled recycled product gas at an outlet of the second stage cyclone separators to quench the temperature of the product gas from the pyrolysis reactor.

[0089] A thirtieth embodiment includes removing the gas phase products from the pyrolysis reactor; separating the gas phase products.

[0039] The method of any one of the fifteenth to twenty-ninth aspects can include the process of any one of the fifteenth to twenty-ninth aspects, further comprising passing the gas phase products through a fluidized bed of particulates in a reactor; exchanging heat between the gas phase products and the particulates in the fluidized bed; and returning the separated particulates to a lower fluidized bed having an outlet for discharging the heated particulates to a pyrolysis reactor.

[0090] A thirty-first embodiment may include any one of the processes described in the twenty-seventh through thirtieth embodiments, further including reacting any unreacted hydrocarbons in the vapor phase product above the fluidized bed and cooling the vapor phase product.

[0091] A thirty-second embodiment can include any one of the processes described in the fifteenth to thirty-first embodiments, further including maintaining a temperature profile of the particulate bed in the pyrolysis reactor based on heating a portion of the particulate removed from a lower portion of the pyrolysis reactor to generate heated particulate in a solid heating section, and returning the heated particulate from the solid heating section to an upper portion of the pyrolysis reactor.

[0092] A thirty-third aspect may include the process of the thirty-second aspect, wherein the temperature profile is further maintained based on introducing a cooled hydrocarbon gas into a lower part of the particulate bed in the pyrolysis reactor.

[0093] A thirty-fourth embodiment may include any one of the processes described in the fifteenth through thirty-third embodiments, further including removing a portion of the particulates from a lower portion of the bed with the solid carbon product.

[0094] A thirty-fifth aspect may include the process of any one of the fifteenth to thirty-fourth aspects, wherein the pyrolysis reactor has a cold wall design.

[0095] A thirty-sixth aspect may include the process of any one of the fifteenth to thirty-fifth aspects, wherein the particulate comprises solid carbon, sand, or catalytic material.

[0096] In a thirty-seventh embodiment, a system for converting hydrocarbon gases to solid carbon and hydrogen products includes a pyrolysis reactor containing a particulate bed, the pyrolysis reactor including a feed gas inlet below the bed, a product gas outlet above the bed, a halogen inlet within the bed, and a solid product outlet for the particulates and solid carbon at the bottom of the pyrolysis reactor; and a separator in fluid communication with the pyrolysis reactor through the product gas outlet at the top of the pyrolysis reactor, the separator configured to separate any particulates in the product gas produced from the pyrolysis reactor and return the particulates to the pyrolysis reactor.

[0097] A thirty-eighth embodiment may include the system of the thirty-seventh embodiment, further including: a first non-mechanical valve disposed at the solid product outlet; and a second non-mechanical valve disposed at the fine particle inlet disposed between the separator and the pyrolysis reactor.

[0098] A thirty-ninth aspect may include the system of the thirty-seventh or thirty-eighth aspect, wherein the separator includes a fluidized bed below the first stage cyclone separator of the separator, the fluidized bed configured to receive a portion of the fine particles from the pyrolysis reactor in the product gas and return the fine particles to the pyrolysis reactor.

[0099] A fortieth aspect may include the system of any one of the thirty-seventh to thirty-ninth aspects, wherein the pyrolysis reactor is configured to contact an oxidant with the hydrocarbons in the pyrolysis reactor and generate heat based on a reaction between the oxidant and the hydrocarbons to heat particulates in the bed of the pyrolysis reactor.

[0100] A forty-first embodiment may include the system of the fortieth embodiment, wherein the oxidizing agent comprises a halogen.

[0101] A forty-second embodiment may include the system of the forty-first embodiment, wherein the halogen comprises chlorine, bromine, or any combination thereof.

[0102] A forty-third embodiment may include the system of the fortieth embodiment, wherein the oxidant comprises oxygen or sulfur.

[0103] A forty-fourth aspect may include the system of any one of the thirty-seventh to forty-third aspects, wherein one or more of the pyrolysis reactors or separators have a cold-wall design.

[0104] A forty-fifth aspect may include the system of any one of the thirty-seventh to forty-fourth aspects, wherein the particulate comprises solid carbon, sand, or catalytic material.

[0105] In a forty-sixth embodiment, a process for converting hydrocarbon gases to solid carbon and hydrogen products includes: introducing a feed stream comprising hydrocarbons into a pyrolysis reactor; introducing an oxidant into the pyrolysis reactor; contacting a first portion of the hydrocarbons with a particulate bed in the pyrolysis reactor; contacting a second portion of the hydrocarbons with the oxidant in the pyrolysis reactor; forming solid oxygen on the particulates; forming gas phase products comprising hydrogen; reacting the second portion of the hydrocarbons with the oxidant to generate heat; and using the heat to heat the particulate bed to a pyrolysis reaction temperature.

[0106] A forty-seventh embodiment may include the process of the forty-sixth embodiment, wherein the heat maintains a temperature profile within the bed.

[0107] A forty-eighth embodiment can include the process of the forty-sixth or forty-seventh embodiment, further including removing gas phase products from the pyrolysis reactor, separating particulates from the gas phase products in a separator, and returning the separated particulates to the pyrolysis reactor.

[0108] A forty-ninth embodiment can include the process of the forty-eighth embodiment, wherein separating particulates from the gas phase product comprises:

[0109] Passing the vapor phase products through a stripper separator.

[0110] A fiftieth embodiment may include the process of the forty-ninth embodiment, further comprising reacting any unreacted hydrocarbons in the vapor phase product in the stripper separator.

[0111] A fifty-first embodiment can include any one of the processes described in the forty-sixth through fiftieth embodiments, further including removing carbon products from the bottom of the bed.

[0112] A fifty-second embodiment may include the process of the fifty-first embodiment, wherein removing a portion of the particulates from the pyrolysis reactor includes passing the portion of the particulates through a non-mechanical valve.

[0113] A fifty-third aspect may include the process of the fifty-second aspect, wherein the non-mechanical valve is an L-valve.

[0114] A fifty-fourth aspect of the present invention relates to the process of the fifty-second aspect, wherein the non-mechanical valve is a loop seal. It can include.

[0115] A fifty-fifth embodiment may include any one of the processes described in the forty-sixth to fifty-fourth embodiments, wherein the oxidizing agent comprises a halogen.

[0116] A fifty-sixth embodiment can include the process of the fifty-fifth embodiment, wherein the halogen includes chlorine.

[0117] A fifty-seventh embodiment can include the process of the fifty-fifth or fifty-sixth embodiment, wherein the halogen comprises bromine.

[0118] A fifty-eighth embodiment may include the process of any one of the forty-sixth to fifty-seventh embodiments, wherein the oxidizing agent comprises oxygen or sulfur.

[0119] A fifty-ninth embodiment may include any one of the processes described in the forty-sixth to fifty-eighth embodiments, wherein the pyrolysis reactor has a cold wall design.

[0120] A sixtieth aspect may include the process of any one of the forty-sixth to fifty-ninth aspects, wherein the particulate comprises solid carbon, sand, or catalytic material.

[0121] A sixty-first embodiment may further include the process of any one of the forty-sixth to sixtieth embodiments, including removing gas phase products from the pyrolysis reactor; passing the gas phase products through a fluidized bed of particulates in a separator; exchanging heat between the gas phase products and the particulates in the fluidized bed; and returning the separated particulates to a lower fluidized bed having an outlet that discharges the heated particulates into the pyrolysis reactor.

[0122] A sixty-second embodiment may include the process of the sixty-first embodiment, further including: introducing the cooled particulates into a separator, wherein the cooled particulates pass through a fluidized bed of particulates in the separator; cooling the gas phase product in the fluidized bed; and heating the particulates in the fluidized bed.

[0123] A 63rd embodiment can include any one of the processes described in the 46th to 62nd embodiments, wherein introducing the hydrocarbon-containing feed stream into the pyrolysis reactor includes countercurrently contacting the feed stream with a particulate bed in the reactor, the feed stream having a lower temperature than the particulates in the particulate bed; cooling the particulates in the particulate bed based on contacting the feed stream with the particulate bed; and heating the feed stream based on contacting the feed stream with the particulate bed.

[0124] Embodiments are described herein with reference to the drawings. However, those skilled in the art will readily understand that the detailed descriptions provided herein with respect to these drawings are for illustrative purposes only, and that the systems and methods are not limited to these restrictive embodiments. For example, those skilled in the art will recognize, in light of the teachings of the present invention description, numerous alternative suitable ways to implement any detailed functionality described herein, depending on the needs of a particular application, beyond the specific implementation options in the following embodiments described and illustrated. That is, there are numerous modifications and variations, too numerous to list, all of which fall within the scope of the present invention description. Also, where appropriate, singular words should be read as plurals, plural words should be interpreted as singular, and masculine nouns should be interpreted as feminine and feminine nouns as masculine, without necessarily implying that the two are mutually exclusive in alternative embodiments.

[0125] The methodologies, compounds, materials, manufacturing techniques, uses, and applications described herein are not to be construed as limiting the scope of the present invention. It should further be understood that the description of the present invention is not limited to the specific methodologies, compounds, materials, manufacturing techniques, uses, and applications described herein, as such may vary. It should also be understood that the terminology used herein is used only for the purpose of describing particular embodiments and is not intended to limit the scope of the systems and methods of the present invention. As used herein and in the appended claims (in this application or any application derived therefrom), it should be noted that the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Thus, for example, a reference to "an element" is a reference to one or more elements and includes equivalents of that reference known to those skilled in the art. All conjunctions used should be understood to have the most inclusive meaning possible. Accordingly, the word "or" should be understood as having the logical "or" definition rather than the logical "exclusive or" definition unless the context otherwise requires. Structures described herein should also be understood to refer to functional equivalents of such structures. Terms that may be construed as approximating should be so understood unless the context clearly indicates otherwise.

[0126] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this description belongs. Although any methods, techniques, devices, or materials similar or equivalent to those described herein can be used in the practice or testing of the systems and methods of the present invention, the preferred methods, techniques, devices, and materials are described. Structures described herein should also be understood to refer to functional equivalents of such structures. The systems and methods of the present invention will now be described in detail with reference to embodiments of the systems and methods of the present invention as illustrated in the accompanying drawings.

[0127] From reading the present disclosure, other variations and modifications will be apparent to persons skilled in the art. Such variations and modifications may involve equivalent and other features which are already known in the art and which may be used instead of or in addition to features already described herein.

[0128] Although the claims consist of particular combinations of features in this application or any further application derived from this application, the scope of the present disclosure should also be understood to include any novel feature or any novel combination of features explicitly or implicitly disclosed herein, or any generalization thereof, whether related to the same system or method as claimed in any claim and whether alleviating all or any of the same technical problems as the systems and methods of the present invention.

[0129] Features that are described in the context of separate embodiments may also be provided in combination in a single embodiment. Conversely, various features that are, for brevity, described in the context of a single embodiment may also be provided separately or in any suitable subcombination. Applicant hereof may file new claims to such features and / or combinations of such features during prosecution of this application or any further application derived therefrom.

Claims

1. 1. A system for converting hydrocarbon gases into solid carbon and hydrogen products, the system comprising: a pyrolysis reactor containing a particulate bed, the pyrolysis reactor comprising a feed gas inlet below the bed, a product gas outlet above the bed, a particulate outlet above the feed gas inlet, a particulate inlet near the top of the bed, and a solid product outlet at the bottom of the pyrolysis reactor; a solid-state heating unit in fluid communication with the particulate outlet and the particulate inlet, the solid-state heating unit configured to receive a portion of the particulate from the pyrolysis reactor through the particulate outlet, heat the portion of the particulate to form heated particulate, and return the heated particulate to the pyrolysis reactor through the particulate inlet; a separator in fluid communication with the pyrolysis reactor through the product gas outlet, the separator configured to separate any particulates in the product gas produced in the pyrolysis reactor and return the particulates to the pyrolysis reactor; Including, the system.

2. 10. The system of claim 1, wherein the pyrolysis reactor has a tapered lower portion and an upper portion having a larger cross-sectional area than the tapered lower portion, and the particulate bed is disposed in the tapered lower portion.

3. 10. The system of claim 1, wherein the particulate bed in the pyrolysis reactor is configured to operate in an spouted bed fluidization regime.

4. 10. The system of claim 1, wherein the separator includes a fluidized bed below a first stage cyclone separator, the fluidized bed configured to receive a portion of the solid product from the first stage cyclone separator and return the solid product to the pyrolysis reactor.

5. The solid state heating portion comprises: a riser configured to receive the portion of the particulates from the pyrolysis reactor; a combustion gas inlet for receiving combustion gas; 2. The system of claim 1, wherein the oxygen-containing gas inlet receives an oxygen-containing gas, and the solid-state heating portion is configured to contact the portion of the particulates with the combustion gas and the oxygen-containing gas, combust the combustion gas to generate combustion product gases, and heat the portion of the particulates to generate heated particulates.

6. The solid heating unit is 6. The system of claim 5, further comprising a second separator configured to receive the portion of the heated particulates downstream of the riser and the combustion product gases, the second separator configured to separate and return a portion of the heated particulates to the pyrolysis reactor.

7. The second separator is a second fluidized bed below the first stage cyclone, the second fluidized bed configured to receive the portion of the heated particulates from the riser; a fluidizing gas inlet in a lower portion of the first stage cyclone, the fluidizing gas inlet configured to receive an oxygen-containing gas and to react the oxygen-containing gas with the combustion product gases within the first stage cyclone; The system of claim 6.

8. The separator is a fluidized bed of fine particles; a product gas inlet in fluid communication with the product gas outlet, the product gas inlet configured to pass the product gas through the fluidized bed; an internal cyclone configured to retain the particulates within the separator; The system of claim 1 , comprising:

9. 10. The system of claim 1, further comprising one or more second stage cyclone separators configured to receive the outlet product gas from the first stage cyclone separator, separate any heated particulates in the outlet product gas, and return the heated particulates to the pyrolysis reactor.

10. 1. A process for converting hydrocarbon gases into solid carbon and hydrogen products, comprising: The process comprises: contacting the hydrocarbons in the feed stream with a bed of particulates in a pyrolysis reactor; forming solid carbon on said particulates; forming a gas phase product comprising hydrogen; removing a portion of the particulates and solid carbon products from the pyrolysis reactor; heating the portion of the particulates from the pyrolysis reactor to produce heated particulates in a solid heating section; returning the heated particulates from the solid heating section to the pyrolysis reactor; A process involving:

11. Heating the portion of the particulates from the pyrolysis reactor to produce heated particulates comprises: contacting the portion of the particulates from the pyrolysis reactor with a combustion gas and an oxygen-containing gas; combusting the combustion gas to produce heat and combustion product gases; and heating the portion of the microparticles with the heat to produce the heated microparticles; The process of claim 10, comprising:

12. passing the heated particulates and the combustion product gases through a first stage cyclone separator; and separating the heated particulates from the combustion product gases and returning the heated particulates to the pyrolysis reactor; 12. The process of claim 11, further comprising:

13. passing a reducing gas through the heated particulates downstream of the first stage cyclone separator and upstream of the pyrolysis reactor; and reducing oxygen-containing species in the combustion product gases entrained with the heated particulates returning to the pyrolysis reactor; 13. The process of claim 12, further comprising:

14. removing said gas phase products from said pyrolysis reactor; separating fine particles from said gas phase product in a first stage cyclone separator having a fluidized bed therebelow; and returning the separated heated particulates to said fluidized bed having an outlet at a lower portion thereof for discharging the heated particulates to said pyrolysis reactor; The process of claim 10 further comprising:

15. Separating the particulates from the gas phase products includes: passing the vapor phase product through an upper portion of the first stage cyclone separator above the fluidized bed, the first stage cyclone separator having a gas inlet at a lower portion thereof for introducing a second hydrocarbon gas; cooling the particulates in the fluidized bed via a thermal decomposition reaction of the second hydrocarbon gas in the bed and cooling the gas phase product in the fluidized bed; and returning the particulates from the fluidized bed to the pyrolysis reactor; 15. The process of claim 14, comprising:

16. 15. The process of claim 14, further comprising one or more second stage cyclone separators configured to receive outlet product gas from the first stage cyclone separator, separate any heated particulates in the outlet product gas, and return the heated particulates to the pyrolysis reactor.

17. 16. The process of claim 15, further comprising one or more second stage cyclone separators configured to receive cooled recycled product gas at an outlet of the second stage cyclone separator to quench the temperature of the product gas from the pyrolysis reactor.

18. removing said gas phase products from said pyrolysis reactor; passing said gas phase product through a fluidized bed of particulates in a separator; exchanging heat between the gas phase product and the particulates in the fluidized bed; returning the separated particulates to the lower fluidized bed, the fluidized bed having an outlet for discharging the heated particulates to the pyrolysis reactor; The process of claim 10 further comprising:

19. reacting any unreacted hydrocarbons in the vapor phase product above the fluidized bed and cooling the vapor phase product; 16. The process of claim 15, further comprising:

20. maintaining a temperature profile of the particulate bed in the pyrolysis reactor based on heating the portion of the particulate removed from the lower portion of the pyrolysis reactor to generate heated particulate in the solid heating section, and returning the heated particulate from the solid heating section to the upper portion of the pyrolysis reactor; The process of claim 10 further comprising:

21. 11. The process of claim 10, further comprising removing a portion of the particulates and solid carbon products from a lower portion of the bed.

22. 1. A system for converting hydrocarbon gases into solid carbon and hydrogen products, the system comprising: a pyrolysis reactor containing a particulate bed, the pyrolysis reactor including a feed gas inlet below the bed, a product gas outlet above the bed, a halogen inlet within the bed, and a solid product outlet at the bottom of the pyrolysis reactor for particulates and solid carbon; A system comprising: a separator in fluid communication with the pyrolysis reactor through the product gas outlet at an upper portion of the pyrolysis reactor, the separator configured to separate any particulates in the product gas produced from the pyrolysis reactor and return the particulates to the pyrolysis reactor.

23. a first non-mechanical valve disposed at the solid product outlet; and a second non-reacting separator disposed at a particulate inlet located between the separator and the pyrolysis reactor; 23. The system of claim 22, further comprising a mechanical valve.

24. 23. The system of claim 22, wherein the separator includes a fluidized bed below the first stage cyclone separator of the separator, the fluidized bed configured to receive a portion of the fine particles from the pyrolysis reactor in the product gas and return the fine particles to the pyrolysis reactor.

25. The pyrolysis reactor comprises: contacting an oxidant with the hydrocarbons in the pyrolysis reactor and generating heat based on a reaction between the oxidant and the hydrocarbons to heat the particulates in the bed of the pyrolysis reactor; 23. The system of claim 22, configured to:

26. 26. The system of claim 25, wherein the oxidizer comprises a halogen, oxygen, or sulfur.

27. 1. A process for converting hydrocarbon gases into solid carbon and hydrogen products, said process comprising: introducing a hydrocarbon-containing feed stream into a pyrolysis reactor; introducing an oxidant into said pyrolysis reactor; contacting a first portion of said hydrocarbons with a particulate bed in said pyrolysis reactor; contacting a second portion of the hydrocarbons with the oxidant in the pyrolysis reactor; forming solid carbon on said particulates; forming a gas phase product comprising hydrogen; reacting the second portion of the hydrocarbon with the oxidant to produce heat; using said heat to heat said particulate bed to a pyrolysis reaction temperature; The process includes:

28. removing said gas phase products from said pyrolysis reactor; separating particulates from said gas phase products in a separator; returning the separated particulates to the pyrolysis reactor; 28. The process of claim 27, further comprising:

29. 30. The process of claim 27, further comprising removing carbon products from a lower portion of the bed.

30. removing the portion of the particulates from the pyrolysis reactor includes passing the portion of the particulates through a non-mechanical valve.

30. The process of claim 29.

31. 28. The process of claim 27, wherein the oxidizing agent comprises a halogen, oxygen, or sulfur.

32. removing said gas phase products from said pyrolysis reactor; passing said gas phase product through a fluidized bed of particulates in a separator; exchanging heat between the gas phase product and the particulates in the fluidized bed; returning the separated particulates to the lower fluidized bed, the fluidized bed having an outlet for discharging the heated particulates to the pyrolysis reactor; 28. The process of claim 27, further comprising:

33. introducing the cooled particulates into the separator, the cooled particulates passing through a fluidized bed of particulates within the separator; cooling the vapor phase product in the fluidized bed; heating the particulates in the fluidized bed; 33. The process of claim 32, further comprising:

34. introducing the feed stream containing the hydrocarbons into a pyrolysis reactor, countercurrently contacting said feed stream with said bed of particulates in said reactor, said feed stream being at a temperature lower than the particulates in said bed of particulates; cooling the particulate in the particulate bed upon contact of the feed stream with the particulate bed; heating the feed stream upon contacting the feed stream with the particulate bed; 28. The process of claim 27, comprising:

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