System for producing hydrocarbon products from synthesis gas

Abstract

A system for producing hydrocarbon products from synthesis gas, the system comprising a synthesis gas generation unit, a Fischer-Tropsch unit, a separation unit, a recycle line, a de-enrichment reactor, a carbon dioxide source, a hydrogen source, and a valve system configured to establish fluid communication in a first configuration or a second configuration.

Description

Technical Field

[0001] The present invention relates to a system for producing hydrocarbon products from synthesis gas and a method of operating such a system.

Background Art

[0002] The Fischer-Tropsch process is a series of chemical reactions that convert a mixture of carbon monoxide and hydrogen into liquid hydrocarbons. These reactions are typically carried out at a temperature of 150 to 300 °C and a pressure of 1 to several tens of atmospheres in the presence of a metal catalyst. The Fischer-Tropsch process ideally includes a series of chemical reactions that produce various hydrocarbons having the formula (C n H 2n+2 ). More useful reactions produce alkanes as follows. (2n + 1)H2 + nCO → C n H 2n+2 + nH2O where n is typically 1 to 100 or more. The formation of methane (n = 1) is undesirable. Most of the alkanes produced tend to be straight-chain and are suitable for the production of middle distillate fuels such as diesel fuel and jet fuel by upgrading. In addition to alkane formation, competing reactions produce small amounts of alkenes, as well as alcohols and other oxygenated hydrocarbons. The by-product water is a by-product separated from the products of the Fischer-Tropsch reaction. The Fischer-Tropsch reaction is a highly exothermic reaction because it is a mixture with CO having a standard reaction enthalpy (ΔH) of -165 kJ / mol.

[0003] International Publication No. 2022 / 079408 describes a process for producing a gas stream containing carbon monoxide, comprising: (a) supplying a gas mixture containing carbon dioxide and hydrogen to a burner located in a reverse water-gas shift vessel, and burning the gas mixture with a quasi-stoichiometric amount of oxygen gas to form a combustion gas mixture containing carbon monoxide, carbon dioxide, hydrogen, and water vapor; (b) passing the combustion gas mixture through a bed of a reverse water-gas shift catalyst located in the reverse water-gas shift vessel to form a crude product gas mixture containing carbon monoxide, water vapor, hydrogen, and carbon dioxide; (c) cooling the crude product gas mixture below the dew point and recovering the condensate to form a dehydrated product gas; (d) removing carbon dioxide from the dehydrated product gas in a carbon dioxide removal unit to form a gas stream containing carbon monoxide; and (e) combining the carbon dioxide recovered by the carbon dioxide removal unit with a gas mixture containing hydrogen and carbon dioxide supplied to the reverse water-gas shift vessel. The product gas stream containing carbon monoxide is supplied to the Fischer-Tropsch hydrocarbon synthesis unit. The Fischer-Tropsch exhaust gas formed by the Fischer-Tropsch hydrocarbon synthesis unit is pre-reformed in a derichment reactor to convert species containing more than one carbon atom into methane. The gas mixture, containing methane and optionally non-condensable hydrocarbons recovered from the Fischer-Tropsch process, is supplied to a reverse water-gas shift unit. As a result, the carbon efficiency of the process is improved.

[0004] If the Fischer-Tropsch hydrocarbon synthesis unit fails, the entire plant must be shut down. Restarting the entire plant, including the synthesis gas production unit, can be time-consuming and may lead to the wasteful use of gaseous flows containing carbon monoxide. An alternative to shutting down the entire plant is to isolate the deenrichment reactor, reduce its pressure, and purge it with nitrogen. However, this would cause many problems, be costly, and wasteful as nitrogen would be released. In addition, the isolation valve downstream of the deenrichment reactor must operate at a temperature of approximately 550°C, which means it is unlikely to function properly.

[0005] The present invention aims to address at least some of the problems related to the prior art, or to provide at least a commercially acceptable alternative solution. [Overview of the project]

[0006] One aspect of this disclosure is a system for producing hydrocarbon products from synthesis gas, (i) Synthesis gas generation unit, A first inlet for supplying a first supply gas flow containing hydrogen and carbon dioxide to the synthesis gas production unit, One or more reaction zones located downstream of the first inlet and in fluid communication with the first inlet, which convert the first supply gas into carbon monoxide-enriched synthesis gas, A first outlet located downstream of one or more reaction zones and in fluid communication with one or more reaction zones, for passing the flow of carbon monoxide-enriched synthesis gas from the synthesis gas generation unit, A synthesis gas generation unit equipped with, (ii) A Fischer-Tropsch unit comprising a reactor for converting a second feed gas containing the carbon monoxide-enriched synthesis gas and recirculated gas mixture into a liquid product mixture containing the hydrocarbon product and water, wherein the Fischer-Tropsch reactor is A second inlet for supplying the second supply gas flow to the Fischer-Tropsch reactor, A Fischer-Tropsch catalyst bed located downstream of the second inlet and in fluid communication with the second inlet, for converting the second supply gas into a mixture of the hydrocarbon product and the liquid product containing water, A second outlet located downstream of the Fischer-Tropsch catalyst bed and in fluid communication with the Fischer-Tropsch catalyst bed allows the liquid product mixture, as well as a gas mixture containing gaseous by-products and unreacted synthesis gas from the Fischer-Tropsch reactor, The Fischer-Tropsch unit is equipped with, (iii) A separation unit located downstream of the second outlet and in fluid communication with the second outlet for separating the liquid product mixture from the gas mixture, the separation unit comprising a third outlet for the gas mixture and a fourth outlet for the liquid product mixture, (iv) A recirculation line for transporting a portion of the gas mixture from the third outlet as the recirculated gas mixture to the second supply gas supplied to the second inlet, (v) A deenrichment reactor for converting a further portion of the gas mixture from the third outlet to form a deenriched methane-containing exhaust gas, A third inlet for supplying the third supply gas, which includes the further portion of the gas mixture and steam from the third outlet, to the deenrichment reactor, A source for supplying a hydrogen stream to the deenrichment reactor via the third or fourth inlet, A deenrichment catalyst bed located downstream of the third and fourth inlets and in fluid communication with the third and fourth inlets, for converting the further portion of the gas mixture and water vapor into a deenrichment methane-containing exhaust gas, and A fifth outlet located downstream of the deenrichment catalyst bed and in fluid communication with the deenrichment catalyst bed, which is for passing the deenrichment methane-containing exhaust gas or the hydrogen flow from the deenrichment reactor, and is in fluid communication with the first inlet. A deenrichment reactor equipped with, (vi) A carbon dioxide source that is in fluid communication with the first inlet, (vii) A hydrogen source that is in fluid communication with the first inlet, (viii) A valve system configured to establish fluid communication in the first or second configuration, Equipped with, In the first configuration, The first outlet of the synthesis gas generation unit is in fluid communication with the second inlet of the Fischer-Tropsch reactor. The third outlet of the separation unit is in fluid communication with the third inlet of the deenrichment reactor. The hydrogen source is not in fluid communication with either the third or fourth inlet of the deenrichment reactor. In this second configuration, The first outlet of the synthesis gas generation unit is not in fluid communication with the second inlet of the Fischer-Tropsch reactor. The third outlet of the separation unit is not in fluid communication with the third inlet of the deenrichment reactor. The hydrogen source is in fluid communication with the third inlet or the fourth inlet of the deenrichment reactor. Regarding the system.

[0007] Another aspect of this disclosure is a method for operating a system that produces hydrocarbon products from synthesis gas, To operate the system in the first configuration, To monitor for malfunctions in the Fischer-Tropsch unit, In response to the presence of a malfunction in the Fischer-Tropsch unit, the system is switched to a second configuration, Regarding methods, including those mentioned above. [Brief explanation of the drawing]

[0008] [Figure 1] This is a flowchart of an example of the system according to the present invention. [Figure 2]Flow diagram of an exemplary system of FIG. 1 in the first configuration. [Figure 3] Flow diagram of an exemplary system of FIG. 1 in the second configuration. [Figure 4] Flow diagram of an exemplary system of FIG. 1 in the first configuration including a valve. [Figure 5] Flow diagram of an exemplary system of FIG. 1 in the second configuration including a valve. **Mode for Carrying Out the Invention**

[0009] In a first aspect, a system for producing hydrocarbon products from synthesis gas, comprising: (i) A synthesis gas production unit having: A first inlet for supplying a flow of a first feed gas containing hydrogen and carbon dioxide to the synthesis gas production unit; One or more reaction zones downstream of the first inlet and in fluid communication with the first inlet for converting the first feed gas into a carbon monoxide-enriched synthesis gas; and A first outlet downstream of the one or more reaction zones and in fluid communication with the one or more reaction zones for passing a flow of the carbon monoxide-enriched synthesis gas from the synthesis gas production unit; A synthesis gas production unit; and (ii) A Fischer-Tropsch unit comprising a reactor for converting the second feed gas containing the carbon monoxide-enriched synthesis gas and a recycle gas mixture into a liquid product mixture containing the hydrocarbon products and water, the Fischer-Tropsch reactor having: A second inlet for supplying a flow of the second feed gas to the Fischer-Tropsch reactor; A Fischer-Tropsch catalyst bed downstream of the second inlet and in fluid communication with the second inlet for converting the second feed gas into the liquid product mixture containing the hydrocarbon products and water. A second outlet located downstream of the Fischer-Tropsch catalyst bed and in fluid communication with the Fischer-Tropsch catalyst bed allows the liquid product mixture, as well as a gas mixture containing gaseous by-products and unreacted synthesis gas from the Fischer-Tropsch reactor, The Fischer-Tropsch unit is equipped with, (iii) A separation unit located downstream of the second outlet and in fluid communication with the second outlet for separating the liquid product mixture from the gas mixture, the separation unit comprising a third outlet for the gas mixture and a fourth outlet for the liquid product mixture, (iv) A recirculation line for transporting a portion of the gas mixture from the third outlet as the recirculated gas mixture to the second supply gas supplied to the second inlet, (v) A deenrichment reactor for converting a further portion of the gas mixture from the third outlet to form a deenriched methane-containing exhaust gas, A third inlet for supplying the third supply gas, which includes the further portion of the gas mixture and steam from the third outlet, to the deenrichment reactor, A source for supplying a hydrogen stream to the deenrichment reactor via the third or fourth inlet, A deenrichment catalyst bed located downstream of the third and fourth inlets and in fluid communication with the third and fourth inlets, for converting the further portion of the gas mixture and water vapor into a deenrichment methane-containing exhaust gas, and A fifth outlet located downstream of the deenrichment catalyst bed and in fluid communication with the deenrichment catalyst bed, which is for passing the deenrichment methane-containing exhaust gas or the hydrogen flow from the deenrichment reactor, and is in fluid communication with the first inlet. A deenrichment reactor equipped with, (vi) A carbon dioxide source that is in fluid communication with the first inlet, (vii) A hydrogen source that is in fluid communication with the first inlet, (viii) A valve system configured to establish fluid communication in the first or second configuration, Equipped with, In the first configuration, The first outlet of the synthesis gas generation unit is in fluid communication with the second inlet of the Fischer-Tropsch reactor. The third outlet of the separation unit is in fluid communication with the third inlet of the deenrichment reactor. The hydrogen source is not in fluid communication with either the third or fourth inlet of the deenrichment reactor. In this second configuration, The first outlet of the synthesis gas generation unit is not in fluid communication with the second inlet of the Fischer-Tropsch reactor. The third outlet of the separation unit is not in fluid communication with the third inlet of the deenrichment reactor. The hydrogen source is in fluid communication with the third inlet or the fourth inlet of the deenrichment reactor. Regarding the system.

[0010] Each aspect or embodiment defined herein may be combined with any other aspect or embodiment unless expressly indicated otherwise. Specifically, any feature indicated as preferred or advantageous may be combined with any other feature indicated as preferred or advantageous.

[0011] In the first configuration, the system can produce hydrocarbon products from synthesis gas. Advantageously, if the Fischer-Tropsch unit, separation unit, and / or recirculation line fail, these components can be isolated from the synthesis gas production unit and deenrichment reactor by operating the valve system to change the system from the first configuration to the second configuration. Thus, the synthesis gas production unit and deenrichment reactor can be kept online while the failure is repaired and the Fischer-Tropsch unit and separation unit are returned to working order. Once the failure is repaired and the Fischer-Tropsch unit and separation unit are returned to working order, the system can be returned to the first configuration for producing hydrocarbon products.

[0012] Keeping the synthesis gas generator unit online during the second configuration reduces the system's startup time after a malfunction is repaired, typically by up to two days. Furthermore, keeping the synthesis gas generator unit warm reduces its temperature cycle, thereby extending its lifespan. By remaining online, the synthesis gas generator unit can continue producing synthesis gas that is ready for reintroduction into the Fischer-Tropsch unit once the entire system is back online.

[0013] By keeping the deenrichment reactor online during the second configuration, the forward flow of gas through the deenrichment reactor can be maintained, which can provide cooling to the equipment. As a result, the catalyst bed temperature can be prevented from becoming dangerously high. Furthermore, by introducing hydrogen into the deenrichment reactor during the second configuration, the deenrichment catalyst can be prevented from becoming wet / oxidized due to the presence of water vapor. In addition, the introduction of hydrogen can prevent the formation of harmful carbonyls (e.g., nickel carbonyls) on the catalyst bed. Such harmful carbonyls can occur if the deenrichment reactor is isolated and not purged while it is being cooled (e.g., to below 200°C) by heat loss to the surroundings due to synthesis gas on the catalyst (e.g., nickel catalyst).

[0014] During the second configuration, keeping both the synthesis gas production unit and the deenrichment reactor online eliminates the need to purge the entire system in the event of a failure in the Fischer-Tropsch unit, separation unit, and / or recirculation line. As a result, less reactant is purged, which means less reactant is lost as a result of the failure.

[0015] As used herein, the term "hydrocarbon product" may encompass species formed from carbon and hydrogen. Hydrocarbon products typically include alkanes and typically contain 5 to 100 or more carbon atoms per molecule.

[0016] As used herein, the terms “syngas” or “synthesis gas” may encompass gas mixtures containing hydrogen (i.e., molecular hydrogen H2) and carbon monoxide (i.e., CO). Syngas may also include other species such as carbon dioxide, water, and methane.

[0017] The system includes a synthesis gas generation unit. Synthesis gas generation units are known in the art.

[0018] The synthesis gas generation unit comprises one or more reaction zones located downstream of a first inlet and in fluid communication with it, which convert a first feed gas into carbon monoxide-enriched synthesis gas. Each of the one or more reaction zones can convert the first feed gas into carbon monoxide-enriched synthesis gas. Alternatively, there may be a first reaction zone that forms an intermediate gas and a second reaction zone that converts the intermediate gas into carbon monoxide-enriched synthesis gas. This conversion includes the reverse water-gas shift conversion of carbon dioxide and hydrogen to carbon monoxide and water. Preferably, at least one of the one or more reaction zones of the synthesis gas generation unit includes a reverse water-gas shift catalyst. Since the reverse water-gas shift reaction is endothermic, heat is supplied to one or more reaction zones. One or more reaction zones may be heated by combustion of fuel, by heat exchange with a suitable high-temperature heat exchange medium, by electrical resistance heating, or by electrical induction heating.

[0019] In some configurations, the synthesis gas generation unit comprises a first reaction zone located downstream of a first inlet and in fluid communication with it, which is in fluid communication with an oxygen gas source and includes a burner for partially combusting a first supply gas together with oxygen gas to form a partially combusted gas mixture, The system may include a second reaction zone located downstream of and in fluid communication with the first reaction zone, the second reaction zone comprising a reverse water-gas shift catalyst bed for converting the partially combusted gas mixture into carbon monoxide-enriched synthesis gas. In such a configuration, the first reaction zone is in fluid communication with an oxygen gas source and a burner. The reaction zone and burner are typically housed in a vessel. The oxygen gas source, such as an oxygen gas tank, oxygen produced by electrolysis of water, oxygen produced by an air separation unit, or oxygen produced by a pressure or vacuum swing adsorption unit, is typically in fluid communication with the first reaction zone via an oxygen gas inlet. Any suitable oxygen gas source may be used. The oxygen gas purity may be at least 85% by volume or 94% by volume, preferably at least 98% by volume or 99% by volume, in order to minimize inert substances such as nitrogen. The oxygen gas source is preferably supplied at a pressure higher than the pressure of the first supply gas supplied to the burner, for example, up to 8 bar higher, because this can create a rate difference that promotes mixing in the burner flame. The oxygen gas source may be preheated as desired to improve combustion. The burner is for partially burning the first supply gas with oxygen gas to form a partially combusted gas mixture. Typically, the burner reacts the oxygen gas with some (but not all) of the hydrogen gas in the first supply gas to form water. In other words, the amount of oxygen gas supplied to the burner is quasi-stoichiometric, i.e., insufficient to burn all the hydrogen. Therefore, the molar ratio of oxygen to hydrogen (O2:H2) is typically less than 0.5:1 and may be in the range of 0.02-0.2:1 or 0.05-0.15:1. Thus, the partially combusted gas mixture typically contains hydrogen, carbon dioxide, and water. By burning hydrogen, heat can be generated for the subsequent reverse water-gas shift reaction. Therefore, hydrogen should preferably be supplied in excess of carbon dioxide so that enough hydrogen remains after combustion to advance the reaction on the reverse water-gas shift catalyst.

[0020] Any burner design may be used, such as a burner used in an autothermal reformer or a secondary steam reformer. The flow may be supplied at a single point or at multiple points. A preferred burner design is one in which the gas mixture is supplied to the neck region of the synthesis gas production unit, and oxygen is supplied to a central conduit that passes through the neck region and opens into the combustion zone. Combustion generates a flame in the combustion zone upstream of the water-gas shift catalyst. Local conditions in the combustion section, particularly in the flame-front region, can be controlled by managing the momentum of the oxygen and gas flow. The water-gas shift vessel may be oriented so that the combustion zone is above the floor of the reverse water-gas shift catalyst. Such a configuration is used in autothermal reformers or secondary steam reformers and may be used in this process, and may be called an autothermal reverse water-gas shift (ARWGS). However, other configurations of the burner and catalyst may be used. The first feed gas is heated by combustion to a temperature typically in the range of 800–1300°C.

[0021] As will be discussed in more detail below, the first supply gas may be preheated to a temperature of preferably 400-1000°C before entering the first inlet. The system may further include a heater for performing the preheating. Alternatively or in addition, the system may include a heat exchanger arranged to transfer heat from the carbon monoxide-enriched synthesis gas to the first supply gas. Before entering the first inlet, the first supply gas may be pre-pressurized to a pressure of preferably 10-50 bara, more preferably 20-30 bara. The system may further include means for performing the pre-pressurization, such as a compressor.

[0022] A synthesis gas production unit comprises one or more reaction zones. At least one of the one or more reaction zones of the synthesis gas production unit may include a reverse water-gas shift catalyst. Reverse water-gas shift catalysts are known in the art. Reverse water-gas shift catalysts are suitable for converting a partially combusted gas mixture into carbon monoxide-enriched synthesis gas. For example, carbon dioxide and hydrogen in a partially combusted gas mixture may be converted to carbon monoxide and water on the reverse water-gas shift catalyst, and any methane present in the partially combusted gas mixture may react with water to produce carbon monoxide, carbon dioxide, and hydrogen. The reaction zone containing the reverse water-gas shift catalyst is typically housed in a vessel, and may be housed in the same vessel as a first reaction zone, with a first inlet and a first outlet formed in the wall of the vessel.

[0023] This system comprises a Fischer-Tropsch unit, which is known in the art. The Fischer-Tropsch unit comprises a reactor for converting a second feed gas, containing a mixture of carbon monoxide-enriched synthesis gas and recirculated gas, into a mixture of hydrocarbon products and a liquid product mixture containing water. The Fischer-Tropsch catalyst bed is typically housed in a vessel, for example, as a fixed bed. A cobalt-containing catalyst is preferred, and for example, a catalyst containing 5-25% by weight of cobalt on a porous alumina, titania, or silica support can be used. Since the reaction is exothermic, the catalyst is typically cooled by direct or indirect heat exchange. A fixed catalyst bed is preferred, in which the catalyst is placed in a reaction tube cooled by boiling water under pressure. In a particularly preferred configuration, the catalyst is placed in a plurality of catalyst supports located in a reaction tube cooled by boiling water under pressure. Such supports are described, for example, in International Publication No. 2016 / 050520(A1). The Fischer-Tropsch unit may include a downstream upgrade unit in which hydrocarbon products from the Fischer-Tropsch reactor are converted into liquid hydrocarbon products such as kerosene, diesel, and naphtha, along with by-products of liquid petroleum gas (LPG) and non-condensable off-gas, typically by hydrogenation using hydrogen gas.

[0024] The second inlet and second outlet are typically formed in the wall of the container.

[0025] The system includes a separation unit located downstream of a second outlet and in fluid communication with it, for separating the liquid product mixture from the gas mixture. Such separation units are known in the art. The separation unit may include a conventional gas-liquid separator for separating the liquid product mixture from the gas mixture.

[0026] The system comprises a deenrichment reactor including a deenrichment catalyst bed. The deenrichment reactor and deenrichment catalyst are known in the art. In the deenrichment reactor, the deenrichment catalyst bed is for converting further portions of the gas mixture and water vapor into a deenriched methane-containing exhaust gas. The deenrichment reactor houses a deenrichment catalyst bed, such as a catalyst used in adiabatic pre-reforming.

[0027] The system further includes a carbon dioxide source that is in fluid communication with the first inlet.

[0028] The system further comprises a hydrogen source. There may be two hydrogen sources. The hydrogen source in fluid communication with the first inlet may be the same as or different from the hydrogen source in fluid communication with the third or fourth inlet. The hydrogen source in fluid communication with the third or fourth inlet typically contains only very low levels of carbon, and more typically, substantially carbon-free. The presence of high levels of carbon in this hydrogen source may lead to carbonyl formation in the deenrichment reactor when the system is in the second configuration. The hydrogen source in fluid communication with the first inlet may also have high purity, but this is not required, and a lower purity hydrogen source can be used if desired.

[0029] The system further comprises a valve system configured to establish fluid communication in a first or second configuration. Suitable valves are known in the art, and those skilled in the art can arrange such valves to establish fluid communication in the first and second configurations. Fluid communication in the system is typically established, for example, through pipes or ducts.

[0030] The system is preferably, (ix) Further comprising a controller for controlling the valve system.

[0031] The controller may take the form of, for example, a pre-programmed computer. The controller may allow for easy switching between a first configuration and a second configuration.

[0032] The system is preferably, (x) A carbon monoxide-enriched synthesis gas flare unit and / or carbon monoxide-enriched synthesis gas storage unit, further comprising: in a first configuration, a first outlet of a synthesis gas generation unit is not in fluid communication with the carbon monoxide-enriched synthesis gas flare unit and / or the carbon monoxide-enriched synthesis gas storage unit; and in a second configuration, a first outlet of a synthesis gas generation unit is in fluid communication with the carbon monoxide-enriched synthesis gas flare unit and / or the carbon monoxide-enriched synthesis gas storage unit.

[0033] In the second configuration, where the Fischer-Tropsch unit is offline, carbon monoxide-enriched synthesis gas is still produced by the synthesis gas generation unit. A carbon monoxide-enriched synthesis gas flare unit can be used to dispose of such carbon monoxide-enriched synthesis gas. A carbon monoxide-enriched synthesis gas storage unit can be used to store carbon monoxide-enriched synthesis gas for use when the Fischer-Tropsch unit comes back online and the system is switched to the second configuration.

[0034] The system is preferably, (xi) means for detecting a malfunction of the Fischer-Tropsch unit, further comprising

[0035] Such means may include, for example, one or more temperature sensors. Malfunction detection may indicate to the operator that the system must be switched from a first configuration to a second configuration. The switchover may be automated by the plant control system or performed manually.

[0036] The system is preferably configured to switch from a first configuration to a second configuration when a malfunction of the Fischer-Tropsch unit is detected. This may allow the system to switch more quickly when a malfunction is detected. Therefore, any adverse effects on the deenrichment reactor caused by a malfunction of the Fischer-Tropsch unit can be reduced.

[0037] The system is preferably configured to switch back to the first configuration once such a malfunction is corrected. This reduces the time required to restart the system.

[0038] When present in one or more reaction zones, the reverse water-gas shift catalyst may be any suitable transition metal oxide catalyst. The reverse water-gas shift catalyst preferably contains nickel, and more preferably contains 3 to 20% by weight of nickel, expressed as NiO on a refractory metal oxide support, based on the total weight of the reverse water-gas shift catalyst. Such catalysts may be particularly suitable for carrying out reverse water-gas shift reactions at favorable temperatures and pressures and with high conversion rates. In addition, such catalysts may be capable of steam reforming any hydrocarbons contained in the first feed gas.

[0039] The reverse water-gas shift catalyst may be located on a suitable refractory metal oxide support. The refractory metal oxide support may include zirconia, alumina, calcium aluminate, magnesium aluminate, titania-magnesia, or mixtures thereof. More preferably, the catalyst includes nickel oxide on zirconia, nickel oxide on α-alumina, nickel oxide on calcium aluminate, or nickel oxide on magnesium aluminate.

[0040] The reverse water-gas shift catalyst may be particulate, or in the form of molded units such as pellets, rings, or extruded products, which may be leaf-shaped or grooved. The catalytically active metal, such as nickel, may be dispersed throughout the particulate catalyst, or it may be present only within an eggshell layer 200 to 1000 micrometers thick on the surface of the refractory support. Alternatively, the catalyst may comprise one or more monolithic supports, such as metal or ceramic foam or honeycomb, supporting the catalytically active metal. Preferably, the catalyst is a particulate catalyst, more preferably a four-hole cylinder, and in particular, leaf-shaped or grooved to provide a higher geometric surface area (GSA) than a solid cylinder of similar size without increasing the pressure drop. 400 to 550 m³ per cubic meter 2 A catalyst having a GSA in the range of [specify range] is preferred.

[0041] If desired, a layer of zirconia balls, pellets, or tiles may be placed on top of the catalyst to protect the catalyst surface from irregularities in the combustion gas flow. The advantage of providing this layer is that it prevents disturbance of the catalyst bed surface.

[0042] The outlet temperature may be in the range of 700°C to 1050°C, preferably 750°C to 950°C.

[0043] The Fischer-Tropsch catalyst preferably comprises cobalt, iron, and / or ruthenium, more preferably cobalt. Such catalysts are particularly effective in catalyzing the Fischer-Tropsch reaction and / or can advantageously allow the reaction to proceed at low temperatures and / or in high yields.

[0044] The Fischer-Tropsch catalyst may be in the form of particulate matter, such as pellets, rings, or molded units such as extruded products, which may be leaf-shaped or grooved.

[0045] The deenrichment catalyst preferably contains nickel, and more preferably has a nickel content in the range of 30 to 90% by weight, expressed as NiO. Such catalysts may be particularly suitable for carrying out the deenrichment reaction at favorable temperatures and pressures and with high conversion rates.

[0046] The deenrichment catalyst may be in the form of particulate matter, such as pellets, rings, or molded units such as extruded products, and these may be leaf-shaped or grooved.

[0047] If an oxygen source is used, the system may further include an electrolysis unit and / or an air separation unit for providing the oxygen source. Preferably, the electricity for the electrolysis unit is generated using renewable energy.

[0048] Preferably, the system further comprises an electrolysis unit for providing a hydrogen source, a high-purity hydrogen separation unit, and / or a hydrogen storage unit.

[0049] Preferably, the system further comprises a hydrocarbon-water separator located downstream of the fourth outlet of the separation unit and in fluid communication with it, for separating the liquid product mixture into a hydrocarbon product stream and a water stream. The water stream may be converted to steam and led to a third inlet of the deenrichment reactor.

[0050] In a further embodiment, the present disclosure relates to a method for operating the system described herein to produce hydrocarbon products from synthesis gas, To operate the system in the first configuration, To monitor for malfunctions in the Fischer-Tropsch unit, In response to the presence of a malfunction in the Fischer-Tropsch unit, the system is switched to a second configuration, Regarding methods, including those mentioned above.

[0051] To avoid misunderstanding, the advantages and preferred features of the first embodiment also apply equally to this embodiment.

[0052] The method is preferably, After switching the system to the second configuration, continue monitoring for any malfunctions in the Fischer-Tropsch unit, In response to the absence of a malfunction in the Fischer-Tropsch unit, the system is returned to the first configuration, It also includes.

[0053] The first feed gas preferably has a hydrogen-to-carbon dioxide molar ratio of 2:1 to 10:1. As discussed above, hydrogen should be supplied in excess of carbon dioxide so that enough hydrogen remains after combustion to advance the reaction on the reverse water-gas shift catalyst. Excess hydrogen is also desirable considering the potential end use of carbon monoxide-containing gas in the Fischer-Tropsch synthesis of hydrocarbons, where the H2:CO ratio is preferably about 2:1. The hydrogen-to-carbon dioxide molar ratio in the first feed gas may be in the range of 1:1 to 5:1. This ratio may vary depending on the conversion of carbon dioxide achieved on the reverse water-gas shift bed and the hydrogen-to-carbon dioxide ratio desired for downstream processes.

[0054] The first supply gas preferably contains 15 to 50 volume% carbon dioxide, preferably 25 to 40 volume% carbon dioxide. The first supply gas supplied to the synthesis gas generation unit preferably contains less than 10 volume% in total of other gases such as water vapor, nitrogen, carbon monoxide, and methane.

[0055] Any suitable carbon dioxide source may be used. The carbon dioxide source is preferably obtained from synthesis gas produced by partial oxidation or steam reforming of hydrocarbons or by vaporization of carbonaceous feedstock, or from flue gas of a furnace or boiler heated by combustion of fossil fuels or carbonaceous waste, or from air or seawater.

[0056] The first supply gas is preheated to a temperature of preferably 400-1000°C, more preferably 450-800°C, and even more preferably 500-600°C before passing through the first inlet of the synthesis gas generation unit. Such preheating can assist combustion.

[0057] The oxygen source, if necessary, provides oxygen in a molar ratio of oxygen to hydrogen (O2:H2) in the first feed gas, preferably less than 0.5:1, preferably 0.02-0.2:1, and more preferably 0.05-0.15:1. Such a ratio ensures partial combustion of hydrogen gas in the first feed gas.

[0058] The carbon monoxide-enriched synthesis gas preferably has a hydrogen-to-carbon monoxide molar ratio of 1.0 to 2.5:1, more preferably 1.2 to 2.5:1, more preferably 1.6 to 2.2:1, and even more preferably 2.0 to 2.1:1. Such ratios are close to the stoichiometric ratios of the Fischer-Tropsch reaction.

[0059] In the first configuration, the temperature of the Fischer-Tropsch catalyst bed is preferably 150°C to 300°C. Such temperatures can enable the Fischer-Tropsch reaction to proceed with high efficiency and high yield.

[0060] The temperature of the third supply gas supplied to the deenrichment reactor is preferably 250 to 650°C, and more preferably 300 to 550°C.

[0061] The third supply gas preferably has a water vapor-to-carbon molar ratio of 0.2:1 to 5:1, more preferably 0.3:1 to 3:1.

[0062] The deenrichment reactor preferably operates at a pressure of 10 to 50 bara.

[0063] In the second configuration, the gas in contact with the deenrichment catalyst preferably has a maximum water vapor to hydrogen (H2) ratio of 10 to 1. This helps to avoid damage to the deenrichment catalyst.

[0064] The present invention includes using the systems and methods described above for a deenrichment reactor for one or more additional parallel deenrichment reactors to which one or more further recirculating flows suitable for conversion in one or more additional parallel deenrichment reactors to a methane-containing gas flow supplied to a synthesis gas production unit. For example, a parallel deenrichment reactor can be used to convert a hydrocarbon recirculating flow from a second separation unit in a Fischer-Tropsch unit to form a deenriched methane-containing recirculating flow that can similarly be supplied to a synthesis gas production unit. Thus, by providing a further valve system as described above, it becomes possible to operate the system in a third or fourth configuration for each of the one or more additional parallel deenrichment reactors. Accordingly, the system and method may comprise a second separation unit, an additional parallel deenrichment reactor, and an additional valve system configured to establish fluid communication in a third or fourth configuration. The method involves operating the system in the third configuration, To monitor for malfunctions in the Fischer-Tropsch unit, In response to the presence of a malfunction in the Fischer-Tropsch unit, the system is switched to the fourth configuration, It further includes, In this third configuration, The first outlet of the synthesis gas production unit is in fluid communication with the second inlet of the Fischer-Tropsch reactor. The outlet of the second separation unit is in fluid communication with the inlet of the further parallel deenrichment reactor. The hydrogen source is optionally not in fluid communication with the inlet of the further parallel deenrichment reactor. In this fourth configuration, The first outlet of the synthesis gas generation unit is not in fluid communication with the second inlet of the Fischer-Tropsch reactor. The outlet of the second separation unit is not in fluid communication with the inlet of the further parallel deenrichment reactor. The hydrogen source is in fluid communication with the inlet of the further parallel deenrichment reactor.

[0065] The present invention will now be described in relation to the following non-limiting embodiments.

[0066] Examples An embodiment of the system according to the present invention will be described with reference to Figures 1 to 5.

[0067] As shown in Figures 1 to 5, an exemplary system (shown as A overall) is for producing hydrocarbon products from synthesis gas. The system comprises a synthesis gas production unit 3 having a first inlet 3a for supplying a flow of first feed gas containing hydrogen and carbon dioxide to the synthesis gas production unit 3; a first reaction zone 3b located downstream of the first inlet 3a and in fluid communication with it, which is in fluid communication with an oxygen gas source 4 and includes a burner 3c for partially combusting the first feed gas with oxygen gas to form a partially combusted gas mixture; a second reaction zone 3d located downstream of the first reaction zone 3b and in fluid communication with it, which includes a reverse water-gas shift catalyst bed 3e for converting the partially combusted gas mixture into carbon monoxide-enriched synthesis gas; and a first outlet 3f located downstream of the second reaction zone 3d and in fluid communication with it for passing a flow of carbon monoxide-enriched synthesis gas from the synthesis gas production unit 3.

[0068] The system further comprises a Fischer-Tropsch unit 5 having a reactor 5a for converting a second feed gas containing a mixture of carbon monoxide-enriched synthesis gas and recirculated gas into a mixture of hydrocarbon products and liquid products containing water, the Fischer-Tropsch reactor 5 comprising a second inlet 5b for supplying a flow of the second feed gas to the Fischer-Tropsch reactor, a Fischer-Tropsch catalyst bed 5c located downstream of the second inlet 5b and in fluid communication with it, for converting the second feed gas into a mixture of hydrocarbon products and liquid products containing water, and a second outlet 5d located downstream of the Fischer-Tropsch catalyst bed 5c and in fluid communication with it for passing the liquid product mixture, as well as a gas mixture containing gaseous by-products and unreacted synthesis gas, out of the Fischer-Tropsch reactor (5).

[0069] The system further comprises a separation unit 6 located downstream of a second outlet 5d and in fluid communication with it, for separating a liquid product mixture from a gas mixture, the separation unit 6 having a third outlet 6a for the gas mixture and a fourth outlet 6b for the liquid product mixture.

[0070] The system further includes a recirculation line 7 for transporting a portion of the gas mixture from the third outlet 6a as a recirculated gas mixture to a second supply gas supplied to the second inlet 5b.

[0071] The system further comprises a deenrichment reactor 8 for converting a further portion of the gas mixture from a third outlet 6a into a deenrichment methane-containing exhaust gas, the deenrichment reactor 8 comprising: a third inlet 8a for supplying a third feed gas containing a further portion of the gas mixture from a third outlet 6a and steam 9 to the deenrichment reactor 8; a fourth inlet 8b for supplying a hydrogen stream to the deenrichment reactor; a deenrichment catalyst bed 8c located downstream of the third inlet 8a and the fourth inlet 8b and in fluid communication with it, the deenrichment catalyst bed 8c for converting a further portion of the gas mixture and steam into a deenrichment methane-containing exhaust gas; and a fifth outlet (8d) located downstream of the deenrichment catalyst bed 8c and in fluid communication with it, the fifth outlet (8d) in fluid communication with the first inlet 3a for allowing the deenrichment methane-containing exhaust gas or hydrogen stream to pass out of the deenrichment reactor.

[0072] The system further comprises a carbon dioxide source 2 in fluid communication with a first inlet 3a, a hydrogen source 1 in fluid communication with the first inlet 3a, and a valve system (see Figures 4 and 5) configured to establish fluid communication in either a first or second configuration.

[0073] The system further comprises a carbon monoxide-enriched synthesis gas flare unit and / or a carbon monoxide-enriched synthesis gas storage unit 10.

[0074] The small loop purge 11 is provided to prevent the undesirable accumulation of inert gases such as nitrogen in the Fischer-Tropsch reaction loop.

[0075] Figures 2 and 3 show the systems in the first and second configurations, respectively, with dashed lines indicating unused lines. As can be seen from Figure 2, in the first configuration, the first outlet 3f of the synthesis gas production unit 3 is in fluid communication with the second inlet 5b of the Fischer-Tropsch reactor 5, the third outlet 6a of the separation unit 6 is in fluid communication with the third inlet 8a of the deenrichment reactor 8, the hydrogen source 1 is not in fluid communication with the fourth inlet 8b of the deenrichment reactor 8, and the first outlet 3f of the synthesis gas production unit 3 is not in fluid communication with the carbon monoxide-enriched synthesis gas flare unit and / or carbon monoxide-enriched synthesis gas storage unit 10.

[0076] As can be seen from Figure 3, in the second configuration, the first outlet 3f of the synthesis gas generation unit 3 is not in fluid communication with the second inlet 5b of the Fischer-Tropsch reactor 5, the third outlet 6a of the separation unit 6 is not in fluid communication with the third inlet 8a of the deenrichment reactor 8, the hydrogen source 1 is in fluid communication with the fourth inlet 8b of the deenrichment reactor 8, and the first outlet 3f of the synthesis gas generation unit 3 is in fluid communication with the carbon monoxide-enriched synthesis gas flare unit and / or carbon monoxide-enriched synthesis gas storage unit 10.

[0077] Figures 4 and 5 show the systems in the first and second configurations, respectively, and illustrate the valve systems. Valves without shading are open, and valves with shading are closed.

[0078] The detailed description above is provided for illustrative and illustrative purposes only and is not intended to limit the scope of the appended claims. Many modifications of the currently preferred embodiments shown herein will be obvious to those skilled in the art and remain within the scope of the appended claims and their equivalents.

Claims

1. A system for producing hydrocarbon products from synthesis gas, (i) Synthesis gas generation unit, A first inlet for supplying a flow of a first supply gas containing hydrogen and carbon dioxide to the synthesis gas generation unit, One or more reaction zones located downstream of the first inlet and in fluid communication with the first inlet, which convert the first supply gas into carbon monoxide-enriched synthesis gas. and A first outlet located downstream of one or more reaction zones and in fluid communication with one or more reaction zones for passing the flow of carbon monoxide-enriched synthesis gas from the synthesis gas generation unit, A synthesis gas generation unit equipped with, (ii) A Fischer-Tropsch unit comprising a reactor for converting a second feed gas containing the carbon monoxide-enriched synthesis gas and recirculated gas mixture into a liquid product mixture containing the hydrocarbon product and water, wherein the Fischer-Tropsch reactor is A second inlet for supplying the second supply gas flow to the Fischer-Tropsch reactor, A Fischer-Tropsch catalyst bed located downstream of the second inlet and in fluid communication with the second inlet, for converting the second supply gas into the liquid product mixture containing the hydrocarbon product and water, A second outlet located downstream of the Fischer-Tropsch catalyst bed and in fluid communication with the Fischer-Tropsch catalyst bed is provided for passing the liquid product mixture and a gas mixture containing gaseous by-products and unreacted synthesis gas from the Fischer-Tropsch reactor. The Fischer-Tropsch unit is equipped with, (iii) A separation unit for separating the liquid product mixture and the gas mixture, located downstream of the second outlet and in fluid communication with the second outlet, comprising a third outlet for the gas mixture and a fourth outlet for the liquid product mixture, (iv) A recirculation line for transporting a portion of the gas mixture from the third outlet to the second supply gas supplied to the second inlet, as the recirculated gas mixture, (v) A deenrichment reactor for converting a further portion of the gas mixture from the third outlet to form a deenriched methane-containing exhaust gas, A third inlet for supplying a third supply gas, which includes the further portion of the gas mixture and water vapor from the third outlet, to the deenrichment reactor, A source for supplying a hydrogen stream to the deenrichment reactor via the third or fourth inlet, A deenrichment catalyst bed located downstream of the third and fourth inlets and in fluid communication with the third and fourth inlets, for converting the further portion of the gas mixture and water vapor into a deenrichment methane-containing exhaust gas, and A fifth outlet located downstream of the deenrichment catalyst bed and in fluid communication with the deenrichment catalyst bed, for passing the deenrichment methane-containing exhaust gas or the hydrogen stream from the deenrichment reactor, and in fluid communication with the first inlet, A deenrichment reactor equipped with, (vi) A carbon dioxide source that is in fluid communication with the first inlet, (vii) A hydrogen source that is in fluid communication with the first inlet, (viiii) A valve system configured to establish fluid communication in the first or second configuration, Equipped with, In the first configuration described above, The first outlet of the synthesis gas generation unit is in fluid communication with the second inlet of the Fischer-Tropsch reactor. The third outlet of the separation unit is in fluid communication with the third inlet of the deenrichment reactor. The hydrogen source is not in fluid communication with either the third or fourth inlet of the deenrichment reactor. In the second configuration described above, The first outlet of the synthesis gas generation unit is not in fluid communication with the second inlet of the Fischer-Tropsch reactor. The third outlet of the separation unit is not in fluid communication with the third inlet of the deenrichment reactor. The hydrogen source is in fluid communication with the third inlet or the fourth inlet of the deenrichment reactor. system.

2. (ix) The system according to claim 1, further comprising a controller for controlling the valve system.

3. (x) further comprising a carbon monoxide-enriched synthesis gas flare unit and / or a carbon monoxide-enriched synthesis gas storage unit, In the first configuration, the first outlet of the synthesis gas generation unit is not in fluid communication with the carbon monoxide-enriched synthesis gas flare unit and / or the carbon monoxide-enriched synthesis gas storage unit. The system according to claim 1, wherein, in the second configuration, the first outlet of the synthesis gas generation unit is in fluid communication with the carbon monoxide-enriched synthesis gas flare unit and / or the carbon monoxide-enriched synthesis gas storage unit.

4. (xi) means for detecting a malfunction of the Fischer-Tropsch unit, further comprising the system according to claim 1.

5. The system according to claim 4, wherein the system is configured to switch from the first configuration to the second configuration when a malfunction of the Fischer-Tropsch unit is detected.

6. The system according to claim 5, wherein the system is configured such that when such a malfunction is corrected, the second configuration switches back to the first configuration.

7. The system according to claim 1, wherein at least one of the one or more reaction zones of the synthesis gas generation unit includes a reverse water-gas shift catalyst.

8. The synthesis gas generation unit comprises a first reaction zone located downstream of the first inlet and in fluid communication with the first inlet, which is in fluid communication with an oxygen gas source and includes a burner for partially combusting the first supply gas with oxygen gas to form a partially combusted gas mixture, The system according to claim 1, comprising: a second reaction zone located downstream of the first reaction zone and in fluid communication with the first reaction zone, the second reaction zone comprising a reverse water-gas shift catalyst bed for converting the partially combusted gas mixture into carbon monoxide-enriched synthesis gas.

9. The system according to claim 7, wherein the reverse water-gas shift catalyst contains nickel.

10. The system according to claim 9, wherein the reverse water-gas shift catalyst contains 3 to 20% by weight of nickel, represented as NiO, on a refractory metal oxide support, based on the total weight of the reverse water-gas shift catalyst.

11. The system according to claim 1, wherein the Fischer-Tropsch catalyst comprises cobalt, iron, and / or ruthenium.

12. The system according to claim 1, wherein the deenrichment catalyst contains nickel.

13. The system according to claim 8, further comprising an electrolysis unit and / or an air separation unit for providing the oxygen source.

14. The system according to claim 1, further comprising an electrolysis unit, a high-purity hydrogen separation unit, and / or a hydrogen storage unit for providing the hydrogen source, which is in fluid communication with the third inlet or the fourth inlet and optionally in fluid communication with the first inlet.

15. A method for producing hydrocarbon products from synthesis gas by operating the system described in claim 1, To operate the aforementioned system in the first configuration, To monitor for malfunctions in the Fischer-Tropsch unit, In response to the presence of a malfunction in the Fischer-Tropsch unit, the system is switched to a second configuration. Methods that include...

16. The method described above is After switching the system to the second configuration, the system continues to monitor for any malfunctions in the Fischer-Tropsch unit, In response to the absence of a malfunction in the Fischer-Tropsch unit, the system is returned to the first configuration. The method according to claim 15, further comprising:

17. The method according to claim 15, wherein the first supply gas has a hydrogen-to-carbon dioxide molar ratio of 2:1 to 10:

1.

18. The method according to claim 15, wherein the first supply gas contains 15 to 50 volume percent of carbon dioxide.

19. The method according to claim 15, wherein the carbon dioxide source is obtained from synthesis gas produced by partial oxidation or steam reforming of hydrocarbons or by vaporization of a carbonaceous feed, or from flue gas of a furnace or boiler heated by combustion of fossil fuels or carbonaceous waste, or from air or seawater.

20. The method according to claim 15, wherein the carbon monoxide-enriched synthesis gas has a hydrogen-to-carbon monoxide molar ratio of 1.0 to 2.5:

1.

21. The method according to claim 15, wherein, in the first configuration, the temperature of the Fischer-Tropsch catalyst bed is 150°C to 300°C.

22. The method according to claim 15, wherein the temperature of the third supply gas supplied to the deenrichment reactor is 250 to 650°C.

23. The method according to claim 15, wherein the third supply gas has a water vapor to carbon molar ratio of 0.2:1 to 5:

1.

24. The method according to claim 15, wherein the deenrichment reactor operates at a pressure of 10 to 50 bara.

25. In the second configuration described above, the gas that comes into contact with the deenrichment catalyst is a maximum water vapor to hydrogen (H) gas of 10 to 1. ２ The method according to claim 15, having the ratio.

26. The system comprises a second separation unit, a further parallel deenrichment reactor, and a further valve system configured to establish fluid communication in a third or fourth configuration. The above method involves operating the system in the third configuration, To monitor for malfunctions in the Fischer-Tropsch unit, In response to the presence of a malfunction in the Fischer-Tropsch unit, the system is switched to the fourth configuration, It further includes, In the third configuration described above, The first outlet of the synthesis gas generation unit is in fluid communication with the second inlet of the Fischer-Tropsch reactor. The outlet of the second separation unit is in fluid communication with the inlet of the further parallel deenrichment reactor. The hydrogen source is optionally not in fluid communication with the inlet of the further parallel deenrichment reactor. In the fourth configuration described above, The first outlet of the synthesis gas generation unit is not in fluid communication with the second inlet of the Fischer-Tropsch reactor. The outlet of the second separation unit is not in fluid communication with the inlet of the further parallel deenrichment reactor. The method according to claim 15, wherein the hydrogen source is in fluid communication with the inlet of the further parallel deenrichment reactor.

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