Methods for the conversion of carbon oxides into sustainable aviation fuel (SAF)

Abstract

A hydrocarbon synthesis plant and process comprising an alcohol synthesis unit and an alcohol-hydrocarbon section, the plant and process including a reforming system for processing a paraffin- and / or olefin-rich by-product stream produced by the plant and process, thereby providing a reformer-based syngas stream that is fed to an inlet of the alcohol synthesis unit.

Description

[Technical Field]

[0001] The present invention relates to a more efficient system (plant) and method for producing hydrocarbons, including olefins, and transportation fuels, such as synthetic kerosene, jet fuel or sustainable aviation fuel (SAF), and optionally diesel, from a carbon oxide-containing feed, e.g., a carbon dioxide-rich feed or a carbon monoxide-rich feed. The plant and method include conversion of the feed to C2-C4 alcohols, e.g., C2 alcohols (ethanol), in an alcohol synthesis unit, and further synthesis of the C2-C4 alcohols in an alcohol-hydrocarbon (ATH) section to an olefin-rich first product. An embodiment of the invention includes further synthesis of the olefin-rich first product to hydrocarbons boiling in the jet fuel range. To improve overall carbon and hydrogen efficiency, an embodiment of the invention includes feeding a paraffin- and / or olefin-rich by-product stream, optionally also an off-gas stream, produced in a hydrocarbon synthesis plant, e.g., the ATH section, to a dedicated reformer, whereby the by-product stream, and optionally also an off-gas stream, are subjected to steam reforming in the dedicated reformer, and the reformer-based syngas thus produced is fed to the alcohol synthesis unit. [Background technology]

[0002] Methods for converting sustainable feedstocks, such as CO2 and biomass, into gasoline or jet fuel via methanol are known. Biomass can first be converted into syngas via gasification, then the syngas can be converted into methanol, for example, in a methanol synthesis loop (hereinafter also referred to as a "methanol loop"), and finally the methanol can be converted into olefins. The olefins can then be oligomerized and hydrogenated to jet fuel, which is a hydrocarbon in the C8-C19 range, e.g., C8-C16 range. CO2 feed can be converted into methanol along with H2 feed, and then the methanol can be converted into jet fuel. Regardless of the main feed, several by-products accompany jet fuel. One of the by-products from such processes is a fraction containing hydrocarbons lighter than the range (C8-19) corresponding to jet fuel, particularly a paraffin- and / or olefin-rich by-product stream, e.g., light paraffins in the C3-C7 range, including propane and / or butane (C3 and / or C4), as well as olefins. This C3 and / or C4 fraction is known as liquefied petroleum gas (LPG). An off-gas stream containing CO2, H2, CH4, higher hydrocarbons, etc. is also typically produced and removed as a tail gas stream.

[0003] Lighter hydrocarbons, such as light paraffins, may often have little commercial value by themselves. Furthermore, in many cases, the off-gas streams have no useful use other than their use in combustion devices that release CO2. Therefore, it would be of interest to be able to recycle these streams as part of the hydrocarbon synthesis process itself, thereby at least improving the overall carbon efficiency (C-efficiency) of the process. Furthermore, recycling a by-product stream comprising lighter hydrocarbons that is a paraffin- and / or olefin-rich stream (hereinafter also referred to as a "paraffin- and / or olefin-rich by-product stream") and / or a waste stream (hereinafter also referred to as an "off-gas stream") generated by the plant or process as a synthesis gas stream via dedicated steam reforming, for example, in a CO2- and H2-based alcohol synthesis plant, enhances the performance of the alcohol synthesis, e.g., ethanol synthesis, as will become apparent from one or more of the following aspects of the present invention.

[0004] EP3730473A1 (Patent Document 1) discloses the use of renewable energy in a methanol synthesis plant, in which steam reforming of a series of hydrocarbon feedstocks, including LPG, is subjected to a syngas generation section upstream of the methanol synthesis to provide methanol synthesis gas, which is further configured, inter alia, so that more of the net energy required by the methanol synthesis plant is provided by non-carbon-based energy sources, renewable energy sources, and / or electricity.

[0005] WO2010143980 (Patent Document 2) discloses a system for integrating methanol production with hydroprocessing of an oil feedstock to produce hydrocarbon products. A steam reformer processes a first feedstock, and C1-C4 hydrocarbons can be separated from the hydrocarbon products and recycled to the first feedstock. Therefore, the steam reformer is installed upstream of the methanol synthesis to provide the main methanol synthesis gas feed, and a hydroprocessing plant with its own feedstock is integrated to benefit from the hydrogen produced in the methanol synthesis.

[0006] Our co-pending European Patent Application No. 22166260.4 discloses the conversion of carbon dioxide to gasoline using, for example, electric steam methane reforming (e-SMR) of a recycled liquefied petroleum gas (LPG) stream. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] EP3730473A1 [Patent Document 2] WO2010143980 [Patent Document 3] EP22166260.4 [Patent Document 4] EP22179912.5 issue [Patent Document 5] US201213452073A [Patent Document 6] EP0535505 [Patent Document 7] WO2019 / 228797A1 [Patent Document 8] WO2019228798 [Patent Document 9] EP20201822 [Patent Document 10] EP21153815 [Non-patent literature]

[0008] [Non-Patent Document 1] “Tubular reforming and autothermal reforming of natural gas - an overview of available processes”, Ib Dybkjaer, Fuel Processing Technology 42 (1995) 85-107 [Non-patent document 2] “Studies in Surface Science and Catalysis,Vol.152,” Synthesis gas production for FT synthesis”;Chapter 4,p.258-352,2004 Summary of the Invention [Problem to be solved by the invention]

[0009] Therefore, there is a need for an efficient method and system that utilizes paraffin- and / or olefin-rich by-product streams, optionally also off-gas streams, and hydrogen-rich streams from sustainable feed-hydrocarbon synthesis plants, e.g., sustainable feed-jet fuel plants, to improve overall C efficiency and hydrogen efficiency (H-efficiency), but avoids drawbacks, in particular avoiding additional CO emissions, and improving alcohol synthesis performance, e.g., ethanol synthesis performance, including in smaller alcohol synthesis units.

[0010] Our co-pending European Patent Application No. 22179912.5 discloses a plant and method in which a reforming system is provided for the dedicated steam reforming of a paraffin and / or olefin rich stream of a jet fuel synthesis plant incorporating the reforming system.

[0011] US201213452073A (Patent Document 5) discloses a method and system for producing high-octane fuel from carbon dioxide and water. A reforming unit downstream of and in fluid communication with a liquid fuel generation unit is configured, for example, to steam reform an unacceptable portion of the separated hydrocarbon product, such as LPG (C3-C4 hydrocarbons) and fuel gas (C1-C2 hydrocarbons). This is because LPG and fuel gas can account for 15-40 wt% of the hydrocarbon product. The resulting synthesis gas (syngas) is supplied to the inlet of a methanol synthesis unit. Because the method or plant is dedicated to the production of olefins and / or jet fuel as hydrocarbon products, and LPG and fuel gas account for less than 15 wt%, e.g., less than 10 wt%, of the hydrocarbon product, this document at least fails to mention the provision of a C2-C4 alcohol synthesis unit. Furthermore, this document at least fails to mention the supply of syngas to this C2-C4 alcohol synthesis unit rather than to the inlet of the methanol synthesis unit. [Means for solving the problem]

[0012] For purposes of this invention: All percentages are by volume unless otherwise stated. All feeds are preheated if necessary.

[0013] The term "synthesis gas" (abbreviated as "syngas") refers to a gas containing hydrogen and carbon oxides, and optionally small amounts of other gases, such as argon, nitrogen, methane, and the like.

[0014] The term "carbon oxides" means CO and / or CO2.

[0015] The term "first syngas feed" refers to a syngas rich in H and CO resulting from the combination of a first H-rich stream and a first CO stream. For example, the first syngas feed may contain about 75% H and about 25% CO containing less than 1% CO.

[0016] The term "secondary syngas feed" refers to a separate syngas feed produced upstream of the alcohol synthesis unit of a hydrocarbon synthesis plant. For example, the second syngas feed comprises H and carbon oxide(s) in a molar ratio of at least 3:1. For example, the second syngas feed has a modulus M of (H - CO) / (CO + CO) of 1.90 to 2.20.

[0017] The "sustainable feed" can be a CO2 feed, an H2 feed, or a combination thereof; or a biomass feed, or a syngas feed produced at least in part from electrolysis.

[0018] The term "first, second, or third, or fourth syngas stream," also referred to as a "reformer-based syngas stream," means a syngas stream removed from a dedicated reforming system that includes a reforming unit (reformer) for processing a by-product stream rich in C1-C4 paraffins and / or olefins. For example, if the reformer is an e-SMR (electrically heated steam methane reformer, also referred to interchangeably as electric steam methane reforming), then the reformer-based syngas stream is an e-SMR-based syngas stream.

[0019] The terms "reforming" and "steam reforming" are used interchangeably.

[0020] A reference to "at least a portion" of a given stream means the entire stream or a portion of it. Correspondingly, a reference to "at least a portion" in relation to a stream or an item such as a unit or section means "a portion of" or "the entirety of."

[0021] The term alcohol synthesis unit refers to an alcohol production unit, where the alcohol is any one of C2 to C4 alcohols or a combination thereof. For example, a C2 alcohol (ethanol, also referred to as EtOH). The alcohol synthesis unit may include a methanol synthesis unit arranged upstream of the C2 to C4 alcohol synthesis unit. The alcohol synthesis unit may include a methanol synthesis unit arranged in parallel with the C2 to C4 alcohol synthesis unit. The alcohol synthesis unit may include only a C2 to C4 alcohol synthesis unit, i.e., the alcohol synthesis unit does not have an upstream methanol synthesis unit or does not have a methanol synthesis unit arranged in parallel with the alcohol synthesis unit. The C2 to C4 alcohol synthesis unit can be catalytic or biocatalytic, for example, for the production of EtOH.

[0022] The term "biocatalytic unit" may be used interchangeably with the term "biocatalytic synthesis unit." A biocatalytic unit includes a biocatalytic reactor, i.e., a bioreactor. Thus, a C2-C4 alcohol synthesis unit may include a biocatalytic reactor.

[0023] The term "ATO" means alcohol-to-olefin conversion.

[0024] The term "OLI" refers to olefin oligomerization.

[0025] The term "HYDRO" refers to the hydrogenation of oligomerized olefins.

[0026] The term "ATH section" refers to the alcohol-hydrocarbon section of a hydrocarbon synthesis plant. The hydrocarbon may be an olefin stream, where the first product is rich in olefins. The hydrocarbon may be a jet fuel stream, e.g., a crude product stream containing hydrocarbons boiling in the jet fuel boiling range. The ATH section includes an ATO reactor and may further include an OLI reactor and a HYDRO reactor.

[0027] The terms "system" and "plant", i.e., process plant, are used interchangeably. Throughout this specification, the term system is used in reference to reforming, i.e., the term "reforming system".

[0028] The terms "section" and "unit" are generally used herein to refer to subsets of a plant or system.

[0029] The term "optionally" can be used interchangeably with "optionally," i.e., an optional aspect.

[0030] The term "comprising" encompasses "comprising only" or "consisting of".

[0031] The terms "comprising" and "containing" are used interchangeably.

[0032] The terms "the invention" or "the present invention" are used interchangeably with "the application" or "this application," respectively.

[0033] The term "and / or" refers to any of three alternatives in relation to a given embodiment. The term "and / or" may be used interchangeably with "at least one" of the three alternatives.

[0034] The use of the singular means at least one.

[0035] Other definitions are provided throughout this application in connection with the description of one or more aspects of the invention.

[0036] In a first general aspect, there is provided a hydrocarbon synthesis plant (200), comprising: a first CO2-rich feed (201) to said plant containing CO2, a first H2-rich feed (202) to said plant containing H2, or a first syngas feed (209) that combines said first CO2-rich feed (201) and said first H2-rich feed (202); or a second syngas feed (205) to said plant that contains carbon oxides and hydrogen; an alcohol synthesis unit (220) configured to receive the first CO2-rich feed (201) and the first H2-rich feed (202), or to receive the first syngas feed (209), or to receive the second syngas feed (205), and to provide an output stream (221) comprising C2 to C4 alcohols; an alcohol-hydrocarbon (ATH) synthesis section (230) configured to receive at least a portion of said effluent stream (221) comprising C2-C4 alcohols; wherein said ATH synthesis section (230) comprises an alcohol-olefins reactor (ATO reactor) to provide an olefin-rich first product (231); said ATH synthesis section (230) is further configured to provide a C1-C4 paraffin and / or olefin-rich by-product stream (242); a reforming system (100) for reforming said by-product stream (1, 242) rich in C1 to C4 paraffins and / or olefins; wherein said reforming system (100) a first reforming feed stream (1) as said by-product stream (242) rich in C1-C4 paraffins and / or olefins, a reforming unit (reformer, 40) arranged to receive said by-product stream (1, 242) rich in C1 to C4 paraffins and / or olefins, to subject it to a steam reforming step, and to provide a reformer-based syngas stream (41, 51, 53, 62); and the reforming system (100) is further configured such that the first reforming feed (1, 242) is less than 15 wt. % of the first product (231) that is rich in olefins; Including, the hydrocarbon synthesis plant (200) is further configured to supply at least a portion of the reformer-based syngas stream (41, 51, 53, 62) to an inlet of the alcohol synthesis unit (220); A hydrocarbon synthesis plant (200) is provided.

[0037] A much simpler plant with a much lower carbon footprint is thereby provided, because reforming is only carried out for a small amount of the internal reforming feed stream, i.e., a paraffin-rich by-product stream, and optionally an off-gas stream. This will be apparent from one or more of the following aspects: In the present application, the by-product and off-gas production of a light hydrocarbon stream in a hydrocarbon synthesis plant (wherein the hydrocarbon is an olefin and / or jet fuel) is less than 15 wt. % of the hydrocarbon product, for example, 10 wt. % or less, for example, 5 wt. %. Even though the by-products and off-gas represent only 15 wt. % or less, for example, about 10 wt. % or 5 wt. % of the hydrocarbon product, they are recycled in the plant or process to increase its overall efficiency, i.e., carbon efficiency (C-efficiency) and hydrogen efficiency (H-efficiency). For example, despite the low percentage of by-products, a dedicated reforming unit is advantageously provided for reforming such by-products and off-gas. The syngas is suitably fed to the inlet of a C2-C4 alcohol synthesis unit, for example, a C2 alcohol (ethanol) synthesis unit, thereby providing an advantageous feed point for the reformed-based syngas. The overall efficiency of the plant and process, i.e., carbon efficiency (C-efficiency) and hydrogen efficiency (H-efficiency), is increased, while at the same time, the performance of the alcohol synthesis unit, particularly the C2-C4 alcohol synthesis unit therein, is improved. A simpler and more compact alcohol synthesis unit is achieved.

[0038] In one embodiment, the hydrocarbon synthesis plant is further configured such that the reformer-based syngas stream (41, 51, 53, 62) comprises up to 50% by volume, e.g., 5 to 45%, e.g., 10 to 40%, of the inlet to the alcohol synthesis unit (220). The inlet may be one or more inlets. Reference to the inlet to the alcohol synthesis unit (220) is understood to refer collectively to all inlets and their associated feed streams. For example, as shown in the accompanying FIG. 1, the inlets to the alcohol synthesis unit (220) may be a first CO-rich feed (201) containing CO to the plant, a first H-rich feed (202) containing H to the plant, or a first syngas feed (209) combining the first CO-rich feed (201) and the first H-rich feed (202), and the reformer-based syngas stream (53).

[0039] In one embodiment, the hydrocarbon synthesis plant (200) does not include a reforming unit located upstream of the alcohol synthesis unit (220) to provide the first (209) or second (205) syngas feed.

[0040] Thus, the first or second syngas feed may be provided via, for example, electrolysis, e.g., electrolysis of water and / or steam to produce hydrogen, without relying on upstream reforming of a hydrocarbon feed, such as natural gas, to provide the syngas feed, thereby achieving a more sustainable solution.

[0041] In one embodiment, the C2 to C4 alcohol is any one of C2 to C4 alcohols or a combination thereof.

[0042] In one embodiment, the olefin-rich first product (231) contains at least 50 wt. % C2 to C9 olefins.

[0043] In one embodiment, the olefin-rich first product (231) contains at least 30 wt. % olefins as hydrocarbons boiling in the jet fuel range, e.g., C8 to C19 hydrocarbons, e.g., C8 to C17 hydrocarbons.

[0044] In one embodiment, the by-product stream (242) rich in C1-C4 paraffins and / or olefins is any one or combination of methane, ethane, ethene (ethylene), propane, propene (propylene), butane, butene (butylene).

[0045] In one embodiment, the alcohol synthesis unit (220) comprises: a methanol synthesis unit (220′) configured to receive the first CO-rich feed (201) and the first H-rich feed (202), or to receive the first syngas feed (209), or to receive the second syngas feed (205), and to provide a methanol-containing effluent stream (211); a C2 to C4 alcohol synthesis unit (220″) configured to receive the methanol-containing effluent stream (211); provided that the C2 to C4 alcohol synthesis unit (220″) is optionally configured to receive a portion of any of the first CO2-rich feed (201), the first H2-rich feed (202), and the first syngas feed (209) and provide the effluent stream (221) comprising C2 to C4 alcohols; Including, The hydrocarbon synthesis plant (200) is configured to supply the at least a portion of the reformer-based syngas stream (41, 51, 53, 62) to an inlet of the C2 to C4 alcohols synthesis unit (220'').

[0046] Thus, in one embodiment, the methanol synthesis unit (220') and the C2 to C4 alcohol synthesis unit (220") are arranged at least partially in series due to the methanol-containing effluent (211) fed to the C2 to C4 alcohol synthesis unit (220"). Portions of any of the first CO2-rich feed (201), first H2-rich feed (202), and first syngas feed (209) are optionally fed to the C2 to C4 alcohol synthesis unit (220"), providing a parallel arrangement for any of these feeds.

[0047] In another embodiment, the alcohol synthesis unit (220) comprises: a methanol synthesis unit (220′) configured to receive the first CO-rich feed (201) and the first H-rich feed (202), or to receive the first syngas feed (209), or to receive the second syngas feed (205), and to provide a methanol-containing effluent stream (211); a C2 to C4 alcohol synthesis unit (220″) configured to receive a portion of any of the first CO2-rich feed (201), the first H2-rich feed (202), and the first syngas feed (209) and to provide an effluent stream (221) comprising C2 to C4 alcohols; provided that the hydrocarbon synthesis plant (200) is optionally configured to supply at least a portion of the reformer-based syngas stream (41, 51, 53, 62) to an inlet of the C2 to C4 alcohol synthesis unit (220″); Includes:

[0048] Thus, in this alternative embodiment, the methanol synthesis unit (220') and the C2 to C4 alcohol synthesis unit (220") are arranged at least partially in parallel, with the units being arranged to receive a portion of any of the first CO2-rich feed (201), the first H2-rich feed (202), and the first syngas feed (209). Suitably, the methanol-containing effluent stream (211), or a portion thereof, is not fed to the C2 to C4 alcohol synthesis unit (220"), i.e., the C2 to C4 alcohol synthesis unit (220") is not arranged to receive the methanol-containing effluent stream (211), or a portion thereof.

[0049] The methanol-containing effluent and the C2-C4 alcohol-containing effluent may be combined into a single stream. The effluent (221) to the alcohol-hydrocarbon (ATH) synthesis section (230) comprises C2-C4 alcohols and further comprises methanol.

[0050] In one embodiment, the plant (200) is further configured to feed a portion of the reformer-based syngas stream (41, 51, 53, 62) that is 50% by volume or less to the inlet of the methanol synthesis unit (220').

[0051] Therefore, the reformer-based syngas is split, for example, 50:50 volume % to the methanol synthesis unit and the C2-C4 alcohol synthesis unit.

[0052] In one embodiment, the plant (200) is further configured to supply a minor portion, not exceeding 20% ​​by volume, of the reformer-based syngas stream (41, 51, 53, 62) to the inlet of the methanol synthesis unit (220').

[0053] It has been found that significant synergistic effects can be achieved by feeding the reformer-based syngas to the C2-C4 alcohol synthesis unit of the alcohol synthesis unit and, optionally, also feeding the reformer-based syngas to its methanol synthesis unit. For example, 99, 90, or 80 volume percent, i.e., a major portion, of the reformer-based syngas stream is fed to the C2-C4 alcohol synthesis unit, while 1, 10, or 20 volume percent, i.e., a minor portion, is fed to the methanol synthesis unit. Therefore, the minor portion of the reformer-based syngas stream (41, 51, 53, 62) fed to the inlet of the methanol synthesis unit (220') is 20 volume percent or less.

[0054] If the alcohol synthesis unit includes a methanol synthesis unit (e.g., a MeOH loop) and a small portion of the reforming-based syngas is fed to it, the required CO / CO molar ratio can be achieved with a relatively small catalyst volume, thereby allowing for a smaller methanol synthesis unit, e.g., a smaller MeOH loop.

[0055] Optionally, the C2 to C4 alcohol synthesis unit (220'') is further configured to receive a portion of any of the first CO2-rich feed (201), the first H2-rich feed (202), and the first syngas feed (209).

[0056] Suitably, said at least part of said reformer-based syngas stream is fed in admixture with said first CO2-rich feed (201) and / or said first H2-rich feed (202), or in admixture with said first syngas feed (209), or in admixture with said second (205) syngas feed. The same applies to said part of said reformer-based syngas stream fed to the inlet of the methanol synthesis unit.

[0057] In one embodiment, the reformer-based syngas stream is a first, second, or third reformer-based syngas stream (41, 51, 53).

[0058] The reforming-based syngas contains not only hydrogen but also a significant amount of carbon oxides (CO x ), particularly CO. The presence of CO in the syngas allows the conversion to C2-C4 alcohols to be carried out with significantly less water generation. Water is conveniently removed from the produced C2-C4 alcohols prior to subsequent conversion to olefins in the alcohol-to-olefin (ATO) reactor, as the presence of water can be detrimental to the ATO reactor catalyst, suitably arranged as a fixed bed in the ATO reactor, and the need to bring water into the plant or process can increase the size of the unit and associated equipment.

[0059] When producing methanol from CO and H, it is significantly more expensive than traditional methanol feed gas (via upstream syngas generation) which contains H, CO, and CO because the reaction from CO forms more water than the reaction from CO as a result of the following reaction: CO + 3H = CHOH + H0 compared to CO + 2H = CHOH. The resulting water also adversely affects the performance of the methanol conversion catalyst, and if the CO concentration is too high, e.g., 90%, the catalyst volume increases by more than 100%. More energy is also required.

[0060] The negative impact of the presence of water is even greater in the case of EtOH production, which involves the use of CO and H as feedstocks. In the case of methanol (CHOH) conversion from CO and H, the molar ratio of the products is CHOH / H0 = 1, i.e., for each volumetric part of ethanol, one volumetric part of water is produced, and in the case of ethanol (CHCHOH) conversion from CO and H, the molar ratio of CHHCOH / H0 is 1 / 3, i.e., for each volumetric part of ethanol, three volumetric parts of water are produced: 2CO + 6H = CHCHOH + 3H0. Therefore, three times more water is produced than in the case of methanol synthesis alone.

[0061] Providing the reformed base syngas to the inlet of the C2-C4 alcohol synthesis unit, e.g., a C2 alcohol synthesis unit (EtOH synthesis unit), along with methanol from an upstream methanol synthesis unit, allows, for example, a feed for EtOH synthesis that produces less water, thereby thermodynamically favoring EtOH production as well, further simplifying the plant and process by limiting the need for water removal, thereby significantly reducing the difficulties associated with water removal in the alcohol synthesis unit, which requires costly and energy-intensive distillation.

[0062] Methanol and water are highly miscible, and therefore, removing water from a water-containing methanol stream is highly inexpedient not only in terms of capital expenditures (and therefore plot size due to the need to provide a large distillation unit) but also in terms of operational expenditures, particularly due to the high energy requirements for distillation. Therefore, a straightforward approach would have been to provide a major portion of the reformer-based syngas stream to the inlet of a methanol synthesis unit, so as to minimize water production as much as possible. In contrast, the present application, in one embodiment, synergistically provides 50% or more by volume of the reformer-based syngas, and therefore a major portion or all of it, as appropriate, to said C2-C4 alcohol synthesis unit, even though C2-C4 alcohols, such as EtOH, are not highly miscible in water. For example, the production of C2 alcohols (EtOH) also produces higher C3-C4 alcohols (propanol and butanol), which are even less miscible in water than EtOH.

[0063] Methanol, for example, is carbonylated to acetic acid and then hydrogenated to EtOH: H + CO → MeOH: MeO H + CO → EtOH (e.g., catalytic process). In a biocatalytic process, H and CO can be converted directly to EtOH.

[0064] The present invention is also applicable to other syngas-C2 to C4 alcohol processes, such as EtOH processes, including those in which there is no upstream methanol production in the C2 to C4 alcohol synthesis unit.

[0065] Accordingly, in one embodiment, the alcohol synthesis unit (220) is a C2 to C4 alcohol synthesis unit (220") configured to directly receive the first CO2-rich feed (201) and the first H2-rich feed (202), or to directly receive the first syngas feed (209), or to directly receive the second syngas feed (209), and to provide the C2 to C4 alcohols effluent stream (221); i.e., the alcohol synthesis unit (220) does not include a methanol synthesis unit (220'), e.g., a methanol synthesis unit (220') upstream of the C2 to C4 alcohol synthesis unit (220").

[0066] The term "direct" means that there are no intermediate steps or units that change the composition of the stream.

[0067] For example, as described above, EtOH may be produced by H + CO → EtOH in a catalytic process, or by H + CO → EtOH in a biocatalytic process, without a prior, upstream, or parallel alcohol synthesis unit. Therefore, the C2-C4 alcohol synthesis unit (220") is also suitably a catalytic or biocatalytic synthesis unit. Also suitably, in the biocatalytic synthesis unit, the inlet H:CO molar ratio, including the reformer-based syngas stream (41, 51, 53, 62), is from 1:1 to 5:1. At these molar ratios, the yield of C2-C4 alcohols, e.g., C2 alcohols (ethanol), is maximized.

[0068] In one embodiment, the ATH synthesis section (230) includes a first separation section configured to receive at least a portion of the olefin-rich first product (231) and provide the C1-C4 paraffin and / or olefin-rich by-product stream (242).

[0069] The first separation section includes a first separation unit, such as a three-phase separator, configured to receive the olefin-rich first product (231) (e.g., containing at least 50 wt. % C2-C9 olefins) and provide a water stream; a gaseous fraction, such as C2-C3 olefins, optionally containing carbon monoxide, carbon dioxide, and hydrogen, as the by-product stream rich in C1-C4 paraffins and / or olefins, such as methane, ethane, ethene (ethylene), propane, propene (propylene), butane, butene (butylene), and combinations thereof; and a liquid hydrocarbon fraction, optionally containing a major portion of the C3 olefins contained in the olefin-rich first product stream (231). The C1-C4 paraffin and / or olefin-rich by-product stream, or a portion thereof, is recycled to the inlet of the alcohol synthesis unit. The first separation section may also include a fractionation unit configured to receive the liquid hydrocarbon fraction and provide a high purity, e.g., at least 93% by volume, C3 olefin product, i.e., a propylene-rich stream of high commercial value, as described in applicant's co-pending European Patent Application No. 22152691.6. From the fractionation unit, an olefin product is produced as the first product enriched in olefins. Accordingly, in one embodiment, in the hydrocarbon synthesis plant (200), the first separation section is also configured to provide a propylene-rich stream.

[0070] Therefore, the ATH section can be considered an alcohol-olefin (ATO) section, and the by-product stream (242) rich in C1-C4 paraffins and / or olefins can be at least a portion of the gaseous fraction as the by-product stream rich in C1-C4 paraffins and / or olefins, which is withdrawn in the first separation section, as described above.

[0071] In one embodiment, the plant is configured to recycle a portion of the by-product stream rich in C1-C4 paraffins and / or olefins to the inlet of the alcohol-olefins (ATO) reactor. This recycle stream dilutes the inlet stream to the ATO reactor, i.e., it dilutes the C2-C4 alcohol-containing effluent stream (221), thereby preventing undesirable adiabatic temperature rise in the ATO reactor, which is conveniently provided as an adiabatic fixed-bed catalytic reactor (fixed-bed reactor).

[0072] This recycle is advantageously a major portion, e.g., 60, 70, 80, 90%, of the by-product stream rich in C1-C4 paraffins and / or olefins, whereby the by-product stream rich in C1-C4 paraffins and / or olefins fed to the reforming system is a minor portion thereof, e.g., 40, 30, 20, 10%, resulting in a reforming system with a significantly reduced plot size compared to the prior art, while at the same time providing significant plant or process synergies by reducing the exothermicity of the ATO reactor in the ATH synthesis section of the plant.

[0073] In one embodiment, the ATH synthesis section (230) further comprises an oligomerization reactor (OLI reactor) configured to receive at least a portion of the olefin-rich first product (231), e.g., after withdrawing the propylene-rich stream, and to provide an oligomerized crude product stream, and a hydrogenation reactor (HYDRO reactor) for providing a crude product (231′) comprising hydrocarbons boiling in the jet fuel range, wherein the ATH synthesis section (230) further comprises: - a separator between the OLI reactor and the HYDRO reactor configured to receive at least a portion of the oligomerized crude product stream and to separate therefrom at least a portion of the by-product stream (242) rich in paraffins and / or olefins; and / or - a separator downstream of the HYDRO reactor, which receives at least one crude product (231') comprising hydrocarbons boiling in the jet fuel range and separates therefrom at least a portion of said by-product stream (242) rich in paraffins and / or olefins; Further includes:

[0074] Thus, the ATH section herein is specifically an alcohol-jet fuel (ATJ) section including an ATO reactor, an OLI reactor, and a HYDRO reactor, and in this case, the by-product stream (242) rich in C1-C4 paraffins and / or olefins can be any one or a combination of the by-product streams.

[0075] The term "hydrocarbons boiling in the jet fuel range" may be used interchangeably with the terms "jet fuel hydrocarbons" or "jet fuel range hydrocarbons," or "jet fuel" or "jet fuel range," respectively. The term refers to C8 to C19 hydrocarbons, e.g., C8 to C17 or C8 to C16 hydrocarbons, boiling in the range of 175 to 300° C. For example, the jet fuel is a sustainable aviation fuel (SAF) that complies with ASTM D7566 and ASTM D4054.

[0076] In one embodiment, the hydrocarbon synthesis plant (200) further comprises: an upgrading section (240) configured to receive at least a portion of the olefin-rich first product (231) or at least a portion of the crude product (231′) comprising hydrocarbons boiling in the jet fuel range, and to provide a jet fuel product stream (241); - said upgrading section (240) arranged to provide a by-product stream (242') rich in paraffins and / or olefins, i.e. another by-product stream (242') rich in paraffins and / or olefins; Includes:

[0077] For purposes of this application, the upgrading section includes a hydrocracking (HCR) reactor and / or a fractionation unit. Thus, in one embodiment, the upgrading section includes a fractionation unit. The upgrading section may further include a hydrogenation (hydro) reactor, e.g., a hydro reactor upstream or downstream of the fractionation unit. Preferably, the upgrading section includes an HCR reactor and a fractionation unit.

[0078] Thus, it will be appreciated that, for example, a HYDRO reactor may be located in the ATJ section of the plant and / or in the upgrade section of the plant, and for example, a HYDRO reactor may be located in the ATJ synthesis section of the plant and an HCR reactor may be located in the upgrade section of the plant.

[0079] Traditionally, steam reforming of the primary hydrocarbon feed gas, such as natural gas, is required upstream of a methanol synthesis unit to provide methanol synthesis gas as a syngas feed. Steam reforming units are typically very costly in terms of capital and operating expenditures and, among other things, involve a significant carbon footprint. The present application, in one embodiment, avoids this and instead integrates a reforming system with a reformer dedicated solely to steam reforming a minor hydrocarbon stream, i.e., a paraffin- and / or olefin-rich by-product stream from the ATH synthesis section or upgrading section of the plant, and optionally, an off-gas stream(s). The sum of these streams still represents a minor stream fed to the reforming system. As explained above, in addition to the associated benefits of enabling smaller alcohol synthesis units, e.g., methanol loops and / or C2-C4 alcohol synthesis units, significantly smaller reformers are required in the reforming system, thus reducing plant plot size and associated capital and operating expenditures. Furthermore, by utilizing, for example, electric steam methane reforming (e-SMR), the unit can be made even more compact and, importantly, carbon emissions are dramatically reduced, since the electric heating can be powered by renewable sources such as wind, solar, or hydropower. Other power sources, such as thermonuclear reactions, are also envisioned.

[0080] Thus, a paraffin- and / or olefin-rich by-product stream may also be provided by the upgrading section of the plant, for example, by a hydrocracking reactor (HCR reactor) and / or fractionation unit located therein. For example, such a paraffin- and / or olefin-rich by-product stream may be a propane- and / or butane-rich stream, such as a liquefied petroleum gas (LPG) stream. The term "propane- and / or butane-rich" means that at least 50%, for example, at least 60%, preferably at least 75% of this by-product stream is propane and / or butane. Typically, LPG contains 70 to 80% by volume of butane, 20 to 30% by volume of propane, and some other hydrocarbons. Therefore, the paraffin- and / or olefin-rich by-product stream may be an LPG stream (LPG feed). LPG is typically a mixture of relatively light hydrocarbons, such as propane and butane. Propylene, butylenes, and various other hydrocarbons, such as C2H6, CH4, etc., are also typically present in LPG in low concentrations. LPG streams may also contain olefins.

[0081] In one embodiment, the hydrocarbon synthesis plant is further configured to provide one or more off-gas streams, i.e., either an off-gas stream, a naphtha stream, or a combination thereof; the one or more off-gas streams (253, 253′) are one or more tail gas streams enriched in CO, H, CH, wherein: - the reforming system is configured to receive at least a portion of any of the one or more off-gas streams, naphtha streams, or combinations thereof; and / or - the C2 to C4 alcohol synthesis unit (220'') of the alcohol synthesis unit (220) comprises a biocatalytic reactor arranged to receive at least a portion of the one or more off-gas stream(s).

[0082] For purposes of this application, the off-gas stream is considered separate from the paraffin and / or olefin rich by-products, the latter being considered a by-product stream and the former being considered a tail gas stream.

[0083] It will be appreciated that the paraffin and / or olefin rich by-product stream may be produced in one or more sections of the plant downstream of the alcohol synthesis unit, for example in the ATH section and / or the upgrading section of the plant.

[0084] The present invention also allows for the production of a naphtha stream, for example, the upgrading section is configured to provide a naphtha stream.

[0085] The terms "naphtha stream" or simply "naphtha" may be used interchangeably. This term refers to hydrocarbons boiling in the naphtha boiling range, meaning C5 to C12 hydrocarbons boiling in the range of 30 to 160° C. For example, it refers to C5 to C9 hydrocarbons, such as C5 to C8 hydrocarbons, including C5 to C9 olefins.

[0086] The off-gas stream(s) may also be produced in one or more sections of the plant, including the ATH section of the plant and / or the upgrading section and / or the alcohol synthesis unit of the plant.

[0087] Therefore, for purposes of this application, the off-gas stream(s) refers to exhaust gas streams containing CO, H, CH, and optionally higher hydrocarbons, also produced in the hydrocarbon synthesis plant. For example, the off-gas stream may originate from the methanol synthesis unit (e.g., a methanol loop); for example, the off-gas stream may originate from a separation unit, such as a low-pressure separation unit, disposed in the methanol synthesis unit of the alcohol synthesis unit. Another off-gas stream may originate from the upgrading section of the hydrocarbon synthesis plant. Another off-gas stream may originate from the ATH section of the hydrocarbon synthesis plant, for example, from the ATO reactor therein, which produces the crude product containing hydrocarbons boiling in the jet fuel range. Another off-gas stream may originate from the upgrading section. As previously mentioned, off-gas streams often have no useful use other than using them in combustion devices, such as fired heaters, which release CO. Now, these off-gas streams are recycled as part of the hydrocarbon synthesis process or plant itself, inter alia, to improve the overall C-efficiency of the plant and process.

[0088] One or more additional off-gas streams of the plant are arranged to be fed, optionally in combination with the paraffin and / or olefin rich by-product stream, to the reforming system and / or to the biocatalytic reactor of the C2 to C4 alcohol synthesis plant.

[0089] Thereby, further synergistic integration is achieved. Off-gas stream(s) are fed to the reforming system and / or to the C2-C4 alcohol synthesis comprising the biocatalytic reactor, i.e., bioreactor. The bioreactor suitably contains a bacterial culture that tolerates or even thrives in the presence of off-gases, thereby increasing the yield of C2-C4 alcohols, such as EtOH, while at the same time keeping the reforming system small-scale, since the latter does not need to handle such off-gases, or only a small portion of them, produced in the hydrocarbon synthesis plant.

[0090] In one embodiment, the reformer (40) in the reforming system (100) can be a steam methane reformer (SMR), i.e., a tubular reformer, an electric steam methane reformer (e-SMR), an autothermal reformer (ATR), a convection-heated reformer, such as a heat exchanger reformer (HER), and combinations thereof.

[0091] For example, steam is optionally added to the reforming system upstream of the reformer, as shown by process steam 22 in accompanying FIG.

[0092] Thus, in a reforming system receiving a paraffin- and / or olefin-rich by-product stream, a primary reformer such as an SMR may be co-located with an ATR; or a convectively heated reformer (convective reformer), e.g., a heat exchange reformer (HER), may be co-located with an ATR. Also, for example, an ATR and an e-SMR may be installed together. The configurations may be in series or parallel.

[0093] Convective reformers may, for example, include one or more bayonet-type reforming tubes, such as HTCR reformers, i.e., Topsaw bayonet reformers, in which heat for reforming is transferred by convection along with radiation. In steam methane reformers (SMRs), i.e., tubular reformers, heat for reforming is transferred primarily by radiation in a radiant furnace. In autothermal reformers (ATRs), partial oxidation of the hydrocarbon feed with oxygen and steam occurs, followed by catalytic reforming. In electrically heated steam methane reformers (e-SMRs), electrical resistance is used to generate heat for catalytic reforming.

[0094] For further information on these reformers, details are provided here with direct reference to the applicant's patents and / or literature. For example, for tubular and autothermal reforming, an overview can be found in "Tubular reforming and autothermal reforming of natural gas - an overview of available processes", Ib Dybkjaer, Fuel Processing Technology 42 (1995) 85-107; and for a description of HTCR, see EP 0 535 505. For a description of ATR, see further below. For a description of the more recent technology, e-SMR, reference is made in particular to WO 2019 / 228797 A1.

[0095] In one embodiment, the catalyst in the steam reforming unit is a reforming catalyst, such as a nickel-based catalyst, which in one embodiment is active in the water-gas shift reaction. Examples of reforming catalysts are Ni / MgAl2O4, Ni / Al2O3, Ni / CaAl2O4, Ru / MgAl2O4, Rh / MgAl2O4, Ir / MgAl2O4, Mo2C, Wo2C, CeO2, Ni / ZrO2, Ni / MgAl2O3, Ni / CaAl2O3, Ru / MgAl2O3, or Rh / MgAl2O3, and noble metals supported on an Al2O3 carrier, although other catalysts suitable for reforming are also contemplated. The catalytically active material may be Ni, Ru, Rh, Ir, or a combination thereof, while the ceramic coating may be Al2O3, ZrO2, MgAl2O3, CaAl2O3, or a combination thereof, potentially mixed with oxides of Y, Ti, La, or Ce. The maximum reactor temperature may be between 850 and 1300°C. The feed gas pressure may be between 15 and 180 bar, preferably about 25 bar. Steam reforming catalysts are also referred to as steam methane reforming catalysts or methane reforming catalysts.

[0096] In another embodiment, the reformer (40) in the reforming system (100) comprises: - Electric steam methane reformer (e-SMR), deployed alone or with an upstream pre-reformer; or - Autothermal reformer (ATR), located alone or with an upstream pre-reformer; is.

[0097] Thus, for example, there is no primary reformer co-located with the e-SMR in a reforming system, such as a steam methane reformer (SMR) located upstream of the e-SMR, or a convection-heated reformer, such as a heat exchanger reformer, located in series or parallel with the e-SMR. However, a pre-reformer (pre-reforming unit) is optionally located upstream of the e-SMR. Thus, the e-SMR may be deployed alone or with an upstream pre-reformer. Such a configuration is also referred to as a standalone e-SMR.

[0098] Similarly, for example, there are no main reformers arranged with the ATR in a reforming system, such as a steam methane reformer (SMR) arranged upstream of an e-ATR, or convection-heated reformers, such as a heat exchange reformer, arranged in series or parallel with the ATR. However, a pre-reformer (pre-reforming unit) is optionally arranged upstream of the ATR. Thus, the ATR may be arranged alone or with an upstream pre-reformer. Such arrangements are also referred to as standalone ATRs.

[0099] This results in an even simpler plant with only a single reformer, optionally including a pre-reformer, and an even lower carbon footprint, especially if the reformer is an e-SMR, since it can be powered by electricity from renewable sources such as wind, solar, hydro, geothermal, or e.g., thermonuclear, the latter sources being considered renewable for the purposes of this application.

[0100] It has been determined that the paraffin- and / or olefin-rich by-product stream, and optionally the off-gas stream recycled through the reforming system, can provide a more efficient and sustainable feedstock for jet fuel conversion. Using the proposed plant layout, this can be achieved without or with significantly less CO2 emissions than conventional methods for similar purposes. Furthermore, the proposed layout also offers the potential for reduced consumption of hydrogen feedstock, thereby increasing hydrogen efficiency. Hydrogen production is power- and capital-cost-intensive, for example, when using an electrolysis unit for hydrogen production. Therefore, if electrolysis for hydrogen production is omitted, the reduced power consumption in the electrolysis unit not only exceeds that in the e-SMR, but also results in a reduction in overall system power consumption. Furthermore, providing an e-SMR with a reformer, installed alone or with an upstream pre-reformer, eliminates internal or external combustion of hydrocarbons, such as natural gas, thereby avoiding the generation of carbon dioxide that cannot be captured by the plant.

[0101] Further details about e-SMR and ATR are provided below.

[0102] In the reforming system, the reforming unit is, in one embodiment, an electric steam methane reformer (e-SMR) configured to receive the first reforming feed stream and perform an electric steam methane reforming (e-SMR) step to provide an e-SMR-based syngas stream.

[0103] Use of e-SMR in this manner allows for recycling of paraffin and / or olefin rich by-product streams, and optionally off-gas streams, thus avoiding or significantly minimizing additional CO2 emissions.

[0104] The e-SMR requires a supply of steam. The e-SMR receives a first reforming feed stream and performs an electric steam methane reforming (e-SMR) step, thereby providing a first syngas stream. The e-SMR uses electrical resistance heating to provide sufficient heating of the reactant streams and catalyst to carry out an effective reforming reaction. The e-SMR preferably includes a pressure shell containing a structured catalyst, the structured catalyst comprising macrostructures of an electrically conductive material. The macrostructures support a ceramic coating, which in turn supports a catalytically active material. The reforming step includes providing electrical power via electrical conductors connecting a power source located outside the pressure shell to the structured catalyst to pass an electric current through the macrostructure material, thereby heating at least a portion of the structured catalyst to a temperature of at least 500°C.

[0105] The power supplied to the e-SMR is suitably generated using renewable energy sources. Suitable e-SMRs for use in the reforming system of the present invention are those described in co-pending applications WO2019228797 and WO2019228798.

[0106] In a steam reforming process, a hydrocarbon and steam stream is catalytically reformed into a product stream of hydrogen and carbon oxides, typically by the following reaction:

[0107] [ka] The water-gas shift (WGS) reaction can also occur:

[0108] [ka] These reactions are in equilibrium at the reactor outlet conditions.

[0109] In the reforming system, the reforming unit is, in another embodiment, an ATR, which is therefore configured to receive a first reforming feed stream together with an oxygen-containing oxidant stream from the electrolysis unit and perform an autothermal reforming step to provide, for example, the first ATR-based syngas stream.

[0110] Using an ATR in this manner also allows for recycling the by-product stream, optionally an off-gas stream, which may be rich in, for example, paraffins and / or olefins, thereby allowing additional CO2 emissions to be avoided or significantly minimized.

[0111] The main components of an ATR reactor are a burner, a combustion chamber, and a catalyst bed housed within a heat-resistant lined pressure shell. In an ATR reactor, partial oxidation or combustion of a hydrocarbon feed with substoichiometric oxygen is followed by steam reforming of the partially combusted hydrocarbon feed stream on a fixed bed of steam reforming catalyst. Due to the high temperature in the combustion chamber, some steam reforming also occurs. This steam reforming reaction is accompanied by a water-gas shift reaction. Typically, gases are at or near equilibrium with the steam reforming and water-gas shift reaction at the outlet of the ATR reactor. The temperature of the outlet gas typically ranges between 850°C and 1100°C. Further details and a complete description of ATR can be found in the art, such as in "Studies in Surface Science and Catalysis, Vol. 152, "Synthesis gas production for FT synthesis"; Chapter 4, pp. 258-352, 2004 (Non-Patent Document 2)."

[0112] Suitable process conditions (temperature, pressure, flow rate, etc.) and suitable catalysts for such steam reforming processes are known in the art.

[0113] In one embodiment of the invention, as already described, the hydrocarbon synthesis plant does not include steam reforming to provide the first or second syngas feed, but optionally the hydrocarbon synthesis plant may include a reverse water gas shift unit (rWGS unit) located upstream of the alcohol synthesis unit to provide the second syngas feed, as will become apparent from the following embodiment.

[0114] Traditionally, steam reforming of a primary hydrocarbon feed gas, such as natural gas, upstream of a methanol synthesis unit is required to provide methanol synthesis gas as a syngas feed. Steam reforming units are typically very costly in terms of capital and operating expenditures, and also carry a significant carbon footprint, among other things.

[0115] As noted above, the present application, in one embodiment, avoids this and instead integrates a reforming system including a reformer dedicated solely to steam reforming a minor hydrocarbon stream, i.e., the paraffin- and / or olefin-rich by-product stream, and optionally an off-gas stream, from the ATH synthesis or upgrading section of the plant. The sum of these streams is still a minor stream fed to the reformer system as at least a portion of the C1-C4 paraffin- and / or olefin-rich by-product stream, advantageously recycled to the ATO reactor, and off-gas, advantageously fed to the C2-C4 alcohol synthesis unit.

[0116] The first CO2-rich feed is fed to the alcohol synthesis unit, such as a methanol synthesis unit therein (as described above, this is conveniently a methanol synthesis loop, or simply a methanol loop, i.e., MeOH loop); and / or to the C2-C4 alcohol synthesis unit therein. For example, the first CO2-rich feed comprises more than 75% CO2, such as more than 90% CO2, for example more than 95% CO2 or more than 99% CO2. In addition to CO2, the first CO2-rich feed may comprise, for example, small proportions of water vapor, oxygen, nitrogen, oxygenates, amines, ammonia, carbon monoxide, and / or hydrocarbons. The first CO2-rich feed suitably comprises only a small amount of hydrocarbons, such as less than 5% hydrocarbons, or less than 3% hydrocarbons, or less than 1% hydrocarbons.

[0117] The first H2-rich feed is provided to the alcohol synthesis unit, such as a methanol synthesis unit therein; and / or to the C2-C4 alcohol synthesis unit therein. The first H2-rich feed optionally consists essentially of hydrogen. The first H2-rich feed of hydrogen is optionally "hydrogen-rich", meaning that the major portion of the feed is hydrogen; i.e., more than 75%, for example more than 85%, preferably more than 90%, more preferably more than 95%, and even more preferably more than 99% of the feed is hydrogen.

[0118] One source of the first H2-rich feed of hydrogen can be one or more electrolyzer units.

[0119] Accordingly, in one embodiment, the hydrocarbon synthesis plant further comprises: an electrolytic section, an electrolysis unit (260) configured to receive a water feed (203), i.e., steam and / or water, and provide (optionally as said first H-rich feed (202)) a second (i.e., other) H-rich feed (202′) containing H, or a portion thereof as said first H-rich feed (202); and / or an electrolysis unit (250) configured to receive a second (i.e., other) first CO2-rich feed (201'), or the CO-containing first CO2-rich feed (201), or a portion thereof, and to provide a CO2-enriched feed (204); Electrolysis section including; - means, such as a mixing unit or junction, for combining the H-containing first or second H-rich feed (202') with the CO-enriched feed (204) to provide the second syngas feed (205); Includes:

[0120] In one embodiment, the reformer (40) in the reforming system (100) comprises an ATR, e.g., a stand-alone ATR, an electrolysis unit (260) configured to receive a water feedstock (203) and provide a first oxygen stream (206), and the hydrocarbon synthesis plant (200) further comprises means, such as a mixing unit or junction, for combining a steam stream (207) with the first oxygen stream (206) to provide an oxidant stream (208); the ATR is configured to receive the oxidant stream (208).

[0121] Also suitably, an electrolysis unit arranged to receive a second CO2-rich feed (201'), or said CO2-containing first CO2-rich feed (201), or a portion thereof, provides a second oxygen stream, and said hydrocarbon synthesis plant further comprises means, such as a mixing unit or junction, for combining said first and / or second oxygen streams with said steam stream to provide said oxidant stream.

[0122] This provides a high degree of integration of process streams in the plant, while at the same time eliminating the need for a large and expensive air separation unit (ASU) that is typically required to generate the oxygen needed when the reformer is an ATR.

[0123] Optionally, a portion of the second CO2-rich feed or a portion of the first CO2-rich feed may bypass the electrolysis unit and be combined with the CO2-enriched feed stream. A certain amount of CO2 is required in the syngas feed, here the second syngas feed, so this bypass allows for adjustment of the syngas feed module M=(H2-CO2) / (CO+CO2) and CO2 content for optimal performance of a methanol synthesis unit located downstream in the alcohol synthesis unit. In one particular embodiment, up to 10% of the first or second CO2-rich feed bypasses the electrolysis unit.

[0124] In addition to hydrogen, the first or second H2-rich feed may contain, for example, water vapor, nitrogen, argon, carbon monoxide, carbon dioxide, and / or hydrocarbons. In some cases, a small percentage of oxygen, typically less than 100 ppm oxygen, may be present in the first or second H2-rich feed. The first or second H2-rich feed optionally contains only a small amount of hydrocarbons, for example, less than 5% hydrocarbons, or less than 3% hydrocarbons, or less than 1% hydrocarbons.

[0125] Optionally, there is also a purification section for removing impurities such as oxygen and hydrocarbons from the first or second H-rich feed, and optionally there is also a purification section for removing impurities such as sulfur-containing compounds, e.g., COS, from, for example, the first CO-rich feed.

[0126] In one aspect, the first CO2-rich feed and the first H2-rich feed are combined into the first syngas feed before being fed to an alcohol synthesis unit.

[0127] For example, the alcohol synthesis plant may include a methanol synthesis unit configured to receive the first CO-rich feed and the first H-rich feed, or the first syngas feed, which is a combination of the first CO-rich feed and the first H-rich feed, and the reformer-based syngas from the reforming system, and optionally a second reformer-based syngas therefrom. A methanol-containing effluent stream is obtained. The process for converting the first CO-rich and first H-rich streams may occur, for example, by compressing them in a first syngas feed compressor and passing the compressed, combined gas as the first syngas feed to a boiling water methanol reactor, e.g., as an embodiment of a methanol reactor in a methanol synthesis unit, where at least a portion of the CO, CO, and H are converted to methanol, followed by separating a purge gas stream from the liquid-phase methanol in a condensation section.

[0128] The crude methanol stream, i.e., methanol-containing effluent stream 211, comprises a majority of methanol; i.e., greater than 50 wt. %, e.g., greater than 75 wt. %, preferably greater than 85 wt. %, and more preferably greater than 90 wt. % of the feed is methanol. Other minor components of this stream include, but are not limited to, higher alcohols, ketones, aldehydes, DME, organic acids, and dissolved gases. Crude methanol also contains water, which typically needs to be removed, e.g., by distillation, to refine the stream to a stream containing greater than 90 wt. % methanol. For example, crude methanol from pure H2 and CO2 will contain about 50 wt. % water. Therefore, a water separation section is conveniently located between the methanol synthesis unit (220') and the C2-C4 alcohol synthesis unit (220'') and configured to remove water from the methanol-containing effluent stream (211). Optionally, a water separation section is also provided between the C2-C4 alcohol synthesis unit (220″), e.g., an EtOH synthesis unit, and the ATH synthesis section (230), configured to remove water from the effluent stream (221) comprising a C2-C4 alcohol, e.g., EtOH.

[0129] The present invention reduces the production of such water, thereby significantly reducing the need for water removal, which is usually high in terms of operational and investment costs due to the high miscibility of water in methanol and EtOH. Furthermore, as also explained above, the presence of water in the downstream ATO reactor in the ATH section of the plant is undesirable. Therefore, the present invention also allows for simple downstream protection of the ATO reactor.

[0130] As noted, a second syngas feed comprising carbon oxides and hydrogen may also be provided to the methanol synthesis unit, this second syngas feed being conveniently provided by combining the second H-rich feed and the CO-enriched feed generated in the electrolysis section.

[0131] This ensures a higher CO / CO molar ratio to the alcohol synthesis unit, and optionally to the methanol synthesis unit therein, and / or to the C2-C4 alcohol synthesis unit therein, which is advantageous in that it requires less catalyst volume, produces less water and therefore requires less purification to remove it downstream, and thereby allows for a smaller methanol synthesis unit, e.g., a smaller MeOH loop, than, for example, simply providing a CO2-rich feed.

[0132] In one embodiment, the hydrocarbon synthesis plant further comprises: - a pyrolysis unit, such as a gasification unit, configured to receive a biomass feedstock and provide a crude syngas feed, and a crude syngas purification section configured to receive the crude syngas feed and provide the second syngas feed; Includes:

[0133] Suitably, at least a portion of said first and / or second oxygen streams from the electrolysis section are subjected to a thermal gasification unit, such as a gasification unit.

[0134] The pyrolysis unit is not a primary reforming unit, the latter being understood to include a catalyst arranged as a fixed bed for converting a hydrocarbon feed gas to syngas, such as an SMR (tubular reformer), or a convection-heated reformer, such as a heat exchange reformer.

[0135] Typically, when gasification is performed to produce a syngas feed for downstream methanol production, the syngas feed is subjected to a shift step, i.e., a water-gas shift step (WGS step), in a WGS section to change the composition of the syngas according to the reaction CO + H2O = CO2 + H2. The WGS can be either sweet (no sulfur in the syngas) or sour (sulfur in the syngas). Finally, a portion of the CO2 is removed in a CO2 removal section. Such sections are large units with high capital and operating expenditures. Furthermore, they result in CO2 being vented from the process. To adjust the modulus of the syngas feed, M = (H2 - CO2) / (CO + CO2), to a target level, e.g., about 2.0 for downstream methanol synthesis, a portion of the syngas typically bypasses the WGS step and the CO2 removal.

[0136] According to the present invention, the second syngas feed may be combined with a reformer-based syngas stream, such as the first, second, or third reformer-based syngas stream of a reforming system, to tailor the feed to a methanol synthesis unit, thus eliminating the need for a WGS section and a CO removal section for the second syngas feed.

[0137] The term "pyrolysis" refers to any decomposition process in which a material is partially decomposed at elevated temperatures, typically from 250°C to 800°C or possibly up to 1000°C, in the presence of substoichiometric amounts of oxygen (including the absence of oxygen). The products may typically be a mixed stream of liquid and gas, as well as a quantity of solid charcoal. The term is intended to encompass processes known as gasification, pyrolysis, partial combustion, or hydrothermal liquefaction.

[0138] In one particular embodiment, the pyrolysis is gasification. Thus, the pyrolysis unit is a gasification unit. Gasification is conveniently carried out in the presence of a gasifying agent, such as oxygen, steam, carbon dioxide, or a combination thereof. Optionally, the gasifying agent is generated in the process; for example, oxygen is provided by electrolysis of steam from the methanol conversion step in a methanol synthesis unit.

[0139] In the crude syngas purification section, impurities such as heavy metals, silica, sulfur, etc. that may be harmful to downstream units and corresponding process steps are removed, for example with the addition of water.

[0140] The term "biomass feedstock" refers to renewable feed, especially solid renewable feed. - Lignocellulosic biomass, including wood, forestry waste, and agricultural waste; and / or - Refuse-derived fuel (RDF) from municipal waste, i.e. municipal solid waste, especially its organic fraction; is.

[0141] The term "lignocellulosic biomass" refers to biomass comprising cellulose, hemicellulose, and optionally lignin. The lignin, or a significant portion thereof, may have been removed, for example, by a prior bleaching step. Lignocellulosic biomass is forestry and / or agricultural waste, and includes biomass derived from plants such as turfgrass, e.g., natural turf (grass derived from natural landscapes), wheat, e.g., straw, oats, rye, reedgrass, bamboo, sugarcane or sugarcane derivatives, e.g., bagasse, corn, and other cereals.

[0142] The term "refuse-derived fuel (RDF)" refers to fuel produced from various types of waste, such as municipal solid waste (MSW), industrial waste, or commercial waste. According to the definition provided by Wikipedia as of April 25, 2022, RDF consists largely of combustible components of waste, such as non-recyclable plastics (excluding PVC), cardboard, labels, and other corrugated materials. These fractions are separated by various processing steps, such as screening, air classification, ballistic separation, separation of ferrous and non-ferrous materials, glass, stone, and other extraneous materials, and crushing to a uniform particle size, or even pelletized to produce a homogenous material that can be used, for example, as a fossil fuel substitute in cement plants, lime plants, coal-fired power plants, or as a reducing agent in steel furnaces.

[0143] The term "municipal solid waste (MSW)" refers to garbage or food waste discarded as everyday items by homes, schools, hospitals, or businesses. MSW includes packaging materials, newspapers, clothing, appliances, and food waste.

[0144] The second syngas feed is rich in CO: for example (on a molar or volumetric basis, dry basis) 40 to 70%, e.g., 60% CO, 1 to 10% CO, e.g., 5% CO, 20 to 40% H, e.g., 30% H, with the remainder being inerts: N + Ar, and H S. This high CO / CO molar ratio in the second syngas feed therefore provides the same advantages as having a high CO / CO molar ratio as described above.

[0145] The reformer-based syngas generated by reforming a paraffin- and / or olefin-rich stream contains CO, CO, and H, and has a composition that ensures a smaller methanol catalyst volume and therefore a smaller CO / CO molar ratio required for a smaller methanol synthesis unit, e.g., a smaller MeOH loop. For example, the composition of the first e-SMR syngas stream, which is the syngas removed from the e-SMR in the reforming system, is (by volume, dry basis) 40 to 70% H, 10 to 30% CO, 2 to 20% CO, and 0.5 to 5% CH.

[0146] To obtain optimized yields in methanol production, the stoichiometric amounts of H, CO, and CO must be considered. Thus, in one embodiment, the first or second syngas feed has a CO / CO molar ratio greater than 1, e.g., greater than 2, e.g., 10 or greater. Also suitably, the first or second syngas feed has a module M=(H−CO) / (CO+CO), defined as a molar content, of 1.80 to 2.20, e.g., 1.95 to 2.10. Similarly, the reformer-based syngas, e.g., the first and second reformer-based syngas streams, may have a CO / CO molar ratio greater than 2, e.g., 10 or greater. Also suitably, the reformer-based syngas has a module M=(H−CO) / (CO+CO), in the range of 1.80 to 2.40, e.g., 1.95 to 2.10.

[0147] In one embodiment, the hydrocarbon synthesis plant (200) comprises: a reverse water gas shift (rWGS) unit, preferably an electric rWGS unit (e-rWGS) unit, configured to receive a portion of the first CO2-rich feed (201) containing CO2 and a portion of the first H2-rich feed (202) containing H2 to provide an rWGS syngas feed; and means, such as a mixing unit or junction, for combining the rWGS syngas feed with the remainder of the first CO2-rich feed (201) containing CO2 and the first H2-rich feed (202) containing H2 to provide the second syngas feed. In one particular embodiment, the rWGS is also configured to receive a portion of the by-product stream (242, 242') that is rich in paraffin fins.

[0148] The rWGS reaction CO + H = CO + H O is endothermic and requires significant heat input. Therefore, the rWGS unit is preferably electrically heated (e-rWGS unit). In this case, optionally, a portion of the paraffin- and / or olefin-rich by-product stream and optionally also a portion of the off-gas stream are sent to the e-rWGS unit, since the e-rWGS unit can also steam reform these streams to some extent.

[0149] For more details on e-rWGS, see, for example, the applicant's WO2022079098 (Patent Document 8) (the e-rWGS section thereof).

[0150] The first or second syngas feed and the reformer base syngas may be combined and fed to the alcohol synthesis unit.

[0151] Thus, in one embodiment, at least a portion of the reformer-based syngas stream (41, 51, 53, 62), e.g., at least a portion of the first, second or third syngas stream (51, 53, 62), is arranged to be fed to the inlet of the alcohol synthesis unit, suitably to the inlet of the C2 to C4 alcohol synthesis unit, in admixture with the CO2-rich feed and / or the H2-rich feed, or in admixture with the first syngas feed, or in admixture with the second syngas feed.

[0152] In one embodiment, the alcohol synthesis unit (220) is configured such that the reformer-based syngas stream (41, 51, 53, 62) is up to 25% by volume of the inlet to the alcohol synthesis unit (220), such as 5, 10, 15, 20%.

[0153] In one embodiment, the alcohol synthesis unit (220), e.g., the methanol synthesis unit (220′) therein, is configured to provide an excess hydrogen stream, i.e., an excess hydrogen stream from the methanol synthesis unit (220′); the plant (200) further includes a hydrogenation section (10) in the reforming system (100), the hydrogenation section (10) being configured to receive the excess hydrogen stream, e.g., a portion of the excess hydrogen stream, from the methanol synthesis unit (220′). Also, for example, the reforming system (100) is configured to combine the first reformate feed stream (1) with the excess hydrogen upstream of the hydrogenation section (10).

[0154] In the hydrogenation section 10, e.g., a hydrogenator, hydrogen or a hydrogen-rich stream, e.g., the excess hydrogen stream from the methanol synthesis unit, may be added to the hydrogenation section, but suitably no dilution stream, e.g., diluent gas, is added to this section, e.g., to the hydrogenator, or to the reformate feed to the hydrogenator.

[0155] Providing an excess hydrogen stream, for example from the methanol synthesis unit, allows for a simpler layout in the plant's reforming system, for example, to eliminate the need for a hydrogen recovery section in the reforming system to provide a hydrogen-rich stream, and thereby the need for a hydrogen compressor to route the hydrogen-rich stream to the hydrogenation section of the reforming system.

[0156] In one embodiment, the reforming system (100) of the plant (200) further includes a separation section (50) configured to receive at least a portion of the first reformer-based syngas stream (41) and separate it into at least the second reformer-based syngas stream (51) and a process condensate (52). The separation section (50) advantageously removes water from the first syngas stream, which is detrimental to use in methanol synthesis.

[0157] The reforming system may include a hydrogenation section configured to receive the first reformate feed stream, i.e., a paraffin- and / or olefin-rich by-product stream, and optionally an off-gas stream, and provide a hydrogenated first reformate feed stream. In the hydrogenation section, the first reformate feed stream is mixed with a hydrogen feed, optionally with an excess hydrogen stream from the plant's methanol synthesis unit, as described above, and passed over a hydrogenation-active catalyst. Again, providing an excess hydrogen stream from the methanol synthesis unit allows for a simpler layout, as shown, for example, in the accompanying FIG. 5, which does not require a hydrogen recovery section in the reformer-based syngas to provide a hydrogen-rich stream, and therefore a hydrogen compressor to send this hydrogen-rich stream to the hydrogenation section. The hydrogenation section may include one or more hydrogenation reactors in series. Hydrogenation converts unsaturated hydrocarbon components, such as olefins, e.g., propylene or butylene, to the corresponding saturated hydrocarbons, which can reduce or avoid carbon formation (in the reforming step) due to the conversion of olefins to alkanes. Suitable hydrogenation catalysts and reactors for such processes are commercially available and known to those skilled in the art.

[0158] The reforming system may also include a desulfurization section configured to receive the hydrogenated first reformate feed stream and provide a desulfurized first and / or second reformate feed stream. Typically, the desulfurization section includes one or more hydrodesulfurization (HDS) reactors. Desulfurization converts sulfur-containing compounds in the first stream into hydrocarbons (typically saturated hydrocarbons) and sulfur-containing compounds (e.g., HS) as by-products. This can reduce catalyst poisoning in subsequent conversion steps. Desulfurization catalysts and reactors suitable for such processes are commercially available and known to those skilled in the art. Materials other than sulfur that may need to be removed in such purification steps include chlorine, dust, and heavy metals.

[0159] A pre-reforming section, i.e., a pre-reformer (or, alternatively, a pre-reforming unit), may be configured to receive the first reforming feed stream and perform a pre-reforming step. A pre-reformed stream is provided. Pre-reforming is an additional reforming step that ultimately allows a syngas having a desired composition, i.e., a composition in which higher hydrocarbons are converted to methane, to be obtained. Pre-reforming is suitably carried out at about 350°C to 700°C to convert higher hydrocarbons as an initial step. Suitable pre-reforming catalysts and reactors for such processes are commercially available and known to those skilled in the art. The pre-reformer unit used in the present invention is a reaction vessel containing a catalyst and is typically adiabatic. In the pre-reforming unit, relatively heavy hydrocarbon components in the hydrocarbon feedstock are steam reformed, and the products of this heavy hydrocarbon reforming are methanated. Those skilled in the art can construct and operate a suitable pre-reformer unit as required. Suitable pre-reformer units for use in the system / method of the present invention are provided in the applicant's co-pending applications EP 20201822 and EP 21153815. The pre-reformed stream comprises methane, hydrogen, carbon monoxide, and carbon dioxide. The pre-reformed stream at the outlet of the pre-reformer may be in the temperature range of 400°C to 500°C.

[0160] Because the first reformer base syngas stream is at an elevated temperature (e.g., 900°C to 1100°C) at the reformer outlet, it can be advantageously heat exchanged with upstream components in the reforming system for efficient energy utilization in the system. Therefore, the reforming system may include one or more heat exchangers arranged to provide heat exchange between the first syngas stream and one or more of the first reforming feed stream, the desulfurized first reforming feed stream, and the boiler feedwater stream. Conveniently, the first reformer base syngas stream is heat exchanged first with the desulfurized first reforming feed stream, then with the boiler feedwater stream, and then with the first reforming feed stream. Alternatively or additionally, one or more electric heaters may be used to increase the temperature of one or more of the first reforming feed stream, the hydrogenated first reforming feed stream, the desulfurized first reforming feed stream, and the boiler feedwater stream.

[0161] As previously explained, the reforming system may further include a second reforming feed stream, which is an off-gas stream comprising CO, H, and CH, said second stream suitably arranged to mix with the first reforming feed stream upstream of the inlet of the reformer, e.g., upstream of the inlet of the e-SMR or ATR.

[0162] In one embodiment, the reforming system includes a hydrogen recovery section configured to receive at least a portion of the second reformer-based syngas stream and provide at least a hydrogen-rich stream and a fourth reformer-based syngas stream; and configured to combine at least a portion of the second reformer-based syngas stream and at least a portion of the fourth reformer-based syngas stream into a combined syngas stream as the third reformer-based syngas stream. The hydrogen recovery section may include a membrane hydrogen separation unit or a PSA (pressure swing adsorption) unit, or both.

[0163] At least a portion of the hydrogen-rich stream obtained from the hydrogen recovery section and / or a portion of the second syngas stream from the separation section may be used in the hydrogenation section of the reforming system. Thus, at least a portion of the hydrogen-rich stream may be combined with the first reforming feed stream, for example, upstream of the hydrogenation section. Alternatively or additionally, recovered H may also be used in the hydrogenation reactor (HYDRO reactor) of the ATH synthesis section.

[0164] Thereby, further integration (through in-house sourcing of hydrogen) and improved hydrogen efficiency of the hydrocarbon synthesis plant are also achieved.

[0165] As noted, the jet fuel product stream meets the requirements to qualify as a sustainable aviation fuel (SAF) in accordance with ASTM D7566 and ASTM D4054, as appropriate.

[0166] In a second general embodiment, there is provided a hydrocarbon synthesis plant (200), comprising: a first CO2-rich feed (201) to said plant containing CO2, a first H2-rich feed (202) to said plant containing H2, or a first syngas feed (209) that combines said first CO2-rich feed (201) and said first H2-rich feed (202); or a second syngas feed (205) to said plant that contains carbon oxides and hydrogen; an alcohol synthesis unit (220) configured to receive the first CO2-rich feed (201) and the first H2-rich feed (202), or to receive the first syngas feed (209), or to receive the second syngas feed (205), and to provide a C2-C4 alcohols-containing effluent stream (221); an alcohol-hydrocarbon (ATH) synthesis section (230) configured to receive at least a portion of the C2-C4 alcohol-containing effluent stream (221); wherein the ATH synthesis section (230) comprises an alcohol-olefins reactor (ATO reactor) to provide an olefin-rich first product (231); and the ATH synthesis section (230) is further configured to provide a C1-C4 paraffin and / or olefin-rich by-product stream (242); a reforming system (100) for reforming said by-product stream (242) rich in C1-C4 paraffins and / or olefins, said reforming system (100) comprising: a first reforming feed stream (1) as said by-product stream (242) rich in C1-C4 paraffins and / or olefins; and a reforming unit (40) configured to receive said by-product stream (1, 242) rich in C1-C4 paraffins and / or olefins and to perform a steam reforming step thereon to provide a reformer-based syngas stream (41, 51, 53, 62); Including, Optionally, the reforming system (100) is further configured such that the first reforming feed (1, 242) is less than 15 wt. % of the first product (231) is olefin-rich; the hydrocarbon synthesis plant (200) is further configured to supply at least a portion of the reformer-based syngas stream (41, 51, 53, 62) to an inlet of the alcohol synthesis unit (220); A hydrocarbon synthesis plant (200) is provided.

[0167] The present invention also provides a method for hydrocarbon synthesis of a first CO2-rich feed (201) containing CO2 and a first H2-rich feed (202) containing H2, or of a first syngas feed (209) combining said first CO2-rich feed (201) and said first H2-rich feed (202); or of a second syngas feed (205) containing carbon oxides and hydrogen, comprising the steps of: - providing a hydrocarbon synthesis plant (200) according to any one of the plant embodiments above; - feeding a CO2-rich feed (201) and an H2-rich feed (202), or the first syngas feed (209); or the second syngas feed (205), to the alcohol synthesis unit (220) and providing an output stream (221) comprising a C2-C4 alcohol, for example, any one or a combination of C2-C4 alcohols; - feeding at least a portion of the C2-C4 alcohol-containing effluent stream (221) from the alcohol synthesis unit (220) to the alcohol-hydrocarbon (ATH) synthesis section (230), i.e., the ATH synthesis section (230) comprising an alcohol-olefin reactor (ATO reactor), to provide an olefin-rich first product (231) (as the hydrocarbon), suitably comprising at least 50 wt. % C2-C9 olefins; and further withdrawing from the ATH synthesis section (230) a by-product stream (242) rich in C1-C4 paraffins and / or olefins, such as a by-product stream (242) rich in methane, ethane, ethene (ethylene), propane, propene (propylene), butane, butene (butylene), or a combination thereof; - feeding at least a portion of the first reforming feed stream (1) as said by-product stream (242) rich in C1-C4 paraffins and / or olefins to a reforming system (100) to carry out a reforming step in a reforming unit (reformer, 40) and provide a reformer-based syngas stream (41, 51, 53, 62), such as a first, second or third reformer-based syngas stream (41, 51, 53); wherein said reforming feed (1, 242) is less than 15 wt. % of said first product (231) rich in olefins; - feeding at least a portion of said reformer-based syngas stream (41, 51, 53, 62) to an inlet of said alcohol synthesis unit (220); Also provided is a method comprising:

[0168] In one embodiment, the reformer-based syngas stream (41, 51, 53, 62) is up to 50% by volume of the inlet to the alcohol synthesis unit (220), such as from 15 to 45%, for example from 20 to 40%.

[0169] In one embodiment, the method does not include steam reforming of a hydrocarbon feed gas to provide the first (209) or the second syngas feed (205).

[0170] In one embodiment, the alcohol synthesis unit (220) comprises a methanol synthesis unit (220') and a C2 to C4 alcohol synthesis unit (220''), and the method further comprises: - feeding the methanol synthesis unit (220'): the first CO2-rich feed (201) and the first H2-rich feed (202); or the first syngas feed (209), or the second syngas feed (205); and providing a methanol-containing effluent stream (211); - feeding the methanol-containing effluent stream (211) to the C2 to C4 alcohol synthesis unit (220'') to provide the C2 to C4 alcohol-containing effluent stream (221); and - feeding said at least a portion of said reformer-based syngas stream (41, 51, 53, 62) to an inlet of said C2 to C4 alcohol synthesis unit (220''); This includes:

[0171] In one embodiment, a portion of the reformer-based syngas stream (41, 51, 53, 62) that is 50% by volume or less is arranged to be fed to the inlet of the methanol synthesis unit (220').

[0172] In one embodiment, the method further comprises feeding one or more off-gas streams, naphtha streams, or any combination thereof, to the reforming system; wherein the one or more off-gas streams are one or more exhaust gas streams enriched in CO, H, or CH. Correspondingly, the first reforming feed stream also comprises one or more off-gas streams (253, 253′), naphtha streams, or any combination thereof.

[0173] In another general aspect, a method for hydrocarbon synthesis of a first CO-rich feed (201) containing CO and a first H-rich feed (202) containing H, or a first syngas feed (209) combining the first CO-rich feed (201) and the first H-rich feed (202); or a second syngas feed (205) containing carbon oxides and hydrogen, comprising the steps of: - providing a hydrocarbon synthesis plant (200) according to any one of claims 1 to 15; - feeding a CO2-rich feed (201) and an H2-rich feed (202), or the first syngas feed (209); or the second syngas feed (205), to the alcohol synthesis unit (220) and providing an output stream (221) comprising a C2-C4 alcohol, for example, any one or a combination of C2-C4 alcohols; - feeding at least a portion of the C2-C4 alcohol-containing effluent stream (221) from the alcohol synthesis unit (220) to the alcohol-hydrocarbon (ATH) synthesis section (230), i.e., the ATH synthesis section (230) comprising an alcohol-olefin reactor (ATO reactor), and providing an olefin-rich first product (231) (as the hydrocarbon), suitably the olefin-rich first product (231) comprising at least 50 wt. % of C2-C9 olefins; and further withdrawing from the ATH synthesis section (230) a by-product stream (242) rich in C1-C4 paraffins and / or olefins, such as a by-product stream (242) rich in methane, ethane, ethene (ethylene), propane, propene (propylene), butane, butene (butylene), or a combination thereof; - feeding at least a portion of the first reforming feed stream (1) as said by-product stream (242) rich in C1 to C4 paraffins and / or olefins to a reforming system (100), carrying out a reforming step in a reforming unit (reformer, 40), and providing a reformer-based syngas stream (41, 51, 53, 62), such as a first, second or third reformer-based syngas stream (41, 51, 53); provided, optionally, that said first reforming feed (1, 242) is less than 15 wt. % of said olefin-rich first product (231); - feeding at least a portion of said reformer-based syngas stream (41, 51, 53, 62) to an inlet of said alcohol synthesis unit (220); A method is provided which includes:

[0174] It will be appreciated that any of the above aspects and associated advantages relating to the hydrocarbon synthesis plant also apply to the process and therefore may be used in connection with the corresponding aspects of the process, and vice versa.

[0175] The technique is illustrated by the following schematic illustration. [Brief explanation of the drawings]

[0176] [Figure 1] FIG. 1 shows one embodiment of a hydrocarbon synthesis plant according to the present invention, in which the hydrocarbon product is an olefin-rich first product. [Figure 2] FIG. 2 illustrates one embodiment of a hydrocarbon synthesis plant according to the present invention, in which the hydrocarbon product is a jet fuel product stream. [Figure 3] FIG. 3 shows another embodiment of a hydrocarbon synthesis plant according to the present invention, wherein the hydrocarbon product is a jet fuel product stream and the alcohol synthesis unit is a C2 to C4 synthesis unit. [Figure 4] FIG. 4 shows another embodiment of a hydrocarbon synthesis plant according to the present invention, in which the hydrocarbon product is a jet fuel product stream and a second syngas comprising carbon oxides and hydrogen is fed to the plant. [Figure 5] FIG. 1 shows one embodiment of the reforming system of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0177] FIG. 1 shows a jet fuel synthesis plant 200 according to the present invention. A reforming system 100 according to FIG. 5 is provided to enable advantageous recycling of the first reformate feed stream 1. It will be understood that in the plant 200, streams 242, 242′ (see also FIG. 2) correspond to the first reformate feed stream 1 in FIG. 5. It will also be understood that the reformate feed streams may also be provided as one or more off-gas streams 253, 253′. The CO2-containing first CO2-rich feed 201 and the H2-containing first H2-rich feed 202, after optionally combining them to form a first syngas feed 209, are sent to an alcohol synthesis unit 220, which includes a methanol synthesis unit 220′ (e.g., methanol loop 220′) and a C2-C4 alcohol synthesis unit 220″, from which an effluent stream 221 is provided comprising either a C2-C4 alcohol, e.g., a C2-C4 alcohol, or a combination thereof, e.g., ethanol (EtOH). The effluent stream 221 is fed to an alcohol-to-hydrocarbon (ATH) synthesis section 230, which includes an alcohol-to-olefins reactor (ATO reactor, not shown), to provide an olefin-rich first product 231. The ATH synthesis section 230 is further configured to provide a C1-C4 paraffin and / or olefin-rich by-product stream 242, such as by-product stream 242 enriched in any one or combination of methane, ethane, ethene (ethylene), propane, propene (propylene), butane, butene (butylene), which is fed to the reforming system 100, which provides a reformer-based stream, such as third e-SMR-based syngas stream 53 (see also FIG. 5 ). This stream is then fed to the alcohol synthesis unit 200, optionally to the inlet of the C2-C4 alcohol synthesis unit 220″. From the reforming system 100, a first or second reformer-based stream, such as the first or second e-SMR-based syngas streams 41, 51 in Figure 5 (not shown here), may also be recycled to the alcohol synthesis unit 220. Furthermore, the hydrocarbon synthesis plant 200 does not include a reforming unit located upstream of the alcohol synthesis unit 220 to provide the first gas feed 209.The reformer-based syngas, such as that shown here as stream 53, is a minor syngas stream compared to the primary syngas stream fed (to the alcohol synthesis unit 220), i.e., the first syngas feed 209 (resulting from combining the first CO2-rich feed 201 and the first H2-rich feed 202), or compared to the second syngas feed 205 resulting from the combination of CO2 electrolysis with water / steam, as shown in FIG. 4, or compared to a second syngas feed also resulting from the pyrolysis of, for example, a biomass feedstock, i.e., a solid renewable feed.

[0178] FIG. 2 shows a hydrocarbon synthesis plant 200 according to another embodiment of the present invention. A reforming system 100 according to FIG. 5 is provided to enable advantageous recycling of the first reformed feed stream 1. It will be understood that in the plant 200 of FIG. 2, streams 242, 242′ correspond to the first reformed feed stream 1 in FIG. 5. It will also be understood that the reformed feed stream may also be provided as one or more off-gas streams 253, 253′. The CO-containing first CO2-rich feed 201 and the H2-containing first H2-rich feed 202, after optionally combining them to form a first syngas feed 209 (not shown), are sent to an alcohol synthesis unit 220, which includes a methanol synthesis unit 220′ (e.g., a methanol loop 220′) and a C2-C4 alcohol synthesis unit 220″, from which an effluent stream 221 is provided comprising either a C2-C4 alcohol, e.g., a C2-C4 alcohol, or a combination thereof, e.g., ethanol (EtOH). A portion of the first CO2-rich feed 201 and / or a portion of the first H2-rich feed 202 containing H may be fed to a C2-C4 alcohol synthesis unit 220'', as shown. The alcohol synthesis unit 220 generates an off-gas stream 253 which is fed to the reforming system 100, as is another off-gas stream 253' from the downstream upgrading section 240. The effluent stream 221 containing C2-C4 alcohols 221 is fed to an ATH synthesis section 230, which may include an ATO reactor (not shown), an olefins reactor (OLI reactor, not shown), and a hydrogenation reactor (HYDRO reactor, not shown), thereby providing a crude product 231' containing hydrocarbons boiling in the jet fuel range, i.e., C8-C19, e.g., C8-C16 hydrocarbons. From the ATH section 230 (here, the alcohol-jet fuel section, or ATJ section), optionally between the OLI reactor and the HYDRO reactor therein and / or downstream of the HYDRO reactor, a paraffin- and / or olefin-rich by-product stream 1, 242 is supplied to the reforming system 100. The downstream upgrading section 240 may also provide a paraffin- and / or olefin-rich by-product stream 242'.A crude product 231' comprising jet fuel range hydrocarbons is fed to the upgrading section 240, where it is upgraded to a jet fuel product stream 241, optionally generating an off-gas stream 253'. The paraffin- and / or olefin-rich by-product streams 242, 242' are fed to the system 100 as previously described, providing a reformer-based stream, such as a third e-SMR-based syngas stream 53, which is then fed to the inlet of the C2-C4 alcohol synthesis unit 220' of the alcohol synthesis unit 220. A portion of the reformer-based syngas stream 53 (not shown) may also be fed to the inlet of the methanol synthesis unit 220'. From the reforming system 100, a first or second reformer-based stream, such as a first or second e-SMR-based syngas stream (41, 51), may also be fed to the C2-C4 alcohol synthesis unit 220'' (not shown).

[0179] FIG. 3 illustrates a hydrocarbon synthesis plant 200 according to another embodiment of the present invention, in which a jet fuel product stream 241 is produced, and an alcohol synthesis unit 220 is a C2 to C4 alcohol synthesis unit 220″ configured to receive a first CO2-rich feed 201 and a first H2-rich feed 202, or to receive the first syngas feed 209 (not shown here, see FIG. 1), or to receive a second syngas feed 205 (see FIG. 4), and to provide the C2 to C4 alcohols-containing effluent stream 221. The alcohol synthesis unit 220 does not include a methanol synthesis unit upstream of the C2 to C4 alcohol synthesis unit 220″. Accordingly, the C2 to C4 alcohol synthesis unit 220" is configured to directly receive the first CO2-rich feed 201 and the first H2-rich feed 202, or directly receive the first syngas feed 209, or directly receive the second syngas feed 205, and provide the C2 to C4 alcohol-containing effluent stream 221. The C2 to C4 alcohol synthesis unit 220" is suitably a catalytic or biocatalytic synthesis unit. An ATH section 230 and an upgrading section 240 are provided to produce a crude product 231' comprising hydrocarbons boiling in the jet fuel range and then a jet fuel product stream 241, as shown in FIG. 2, and a reforming system 100, similarly described in connection with FIG. 2 and described in additional detail in connection with FIG. 5, are also provided.

[0180] Figure 4 shows a hydrocarbon synthesis plant 200 similar to Figures 2 or 3, in which an alcohol synthesis unit 220 is supplied with a second syngas feed 205. The plant 200 includes an electrolysis unit 260 configured to receive an aqueous feedstock 203, i.e., steam and / or water, and provide a second H-rich feed 202' containing H (optionally as the first H-rich feed 202), and a first oxygen stream 206. The plant 200 further includes an electrolysis unit 250 configured to receive a second CO-rich feed 201', or the first CO-rich feed 201 of Figure 2 containing CO, or a portion thereof, and to provide a CO-enriched feed stream 204 and a second oxygen stream 206'. Optionally, a portion of the second CO-rich feed 201' may bypass the electrolysis unit 250 and be combined with the CO-enriched feed stream 204 (not shown). A mixing unit or junction (not shown) combines streams 202′ and 204 into a second syngas feed 205, which has a CO / CO molar ratio greater than 1, such as a CO / CO molar ratio of 10 or greater, to enable a more reactive syngas for the alcohol synthesis unit 220. A mixing unit or junction (not shown) combines a steam stream 207 with the first oxygen stream 206 and / or the second oxygen stream 206′ to provide an oxidant stream 208, which may be fed to the reforming system 100, where the reformer 40 is suitably an autothermal reformer (ATR). The third reformer base syngas 53 is optionally mixed with the second syngas feed 205 (not shown) to provide a more reactive feed gas to the inlet to the alcohol synthesis unit 220, for example to the inlet to the methanol synthesis unit 220′ or to the inlet to the C2 to C4 alcohol synthesis unit 220″ contained therein (not shown).

[0181] 5 shows one layout of the reforming system 100. The first reformer feed stream 1, which corresponds to the paraffin- and / or olefin-rich by-product streams 242, 242′ in FIG. 2, is compressed in a first pump 69. It will be understood that the reformer feed may also be provided as one or more off-gas streams 253, 253′. In this layout, the compressed first reformer feed stream is mixed with the hydrogen-rich stream 61 in a mixer 68 and then passes through heat exchangers 64, 63 to exchange heat with the first syngas stream 41. The heated first reformer feed stream 1 is hydrogenated in a hydrogenation section 10 to provide a hydrogenated first reformer feed stream 11, which is then desulfurized in a desulfurization section 20 to provide a desulfurized first reformer feed stream 21. As shown in Figure 5, in the hydrogenation section 10, e.g., a hydrogenator, hydrogen or a hydrogen-rich stream, e.g., stream 61, may be added to the hydrogenation section 10; however, suitably, no dilution stream, e.g., dilution gas, is added to this section, e.g., the hydrogenator, or to the reforming feed to the hydrogenator. The desulfurized first reforming feed stream 21 may be mixed with process steam 22, and this combined stream is again heat exchanged with the first syngas stream 41. The desulfurized first reforming feed stream 21 is pre-reformed in a pre-reforming section 30 to provide a pre-reformed stream 31. The pre-reformed stream 31 is subjected to electric steam methane reforming (e-SMR) in an electric steam methane reformer (e-SMR, 40) to provide an e-SMR-based syngas stream, e.g., first syngas stream 41. Electric power for the electric steam methane reforming (e-SMR) is indicated by a "lightning" symbol. The first syngas stream 41 is then heat exchanged with boiler feed water 90 in waste heat boiler 62 to provide export stream 91, which may optionally be used as feed for the plant's electrolysis unit. The first syngas stream 41 then passes through heat exchangers 64, 63 (as previously described) and then is heat exchanged once more with boiler feed water 90 in heat exchanger 65. Additional cooling is provided in chiller unit 66. The first e-SMR-based syngas stream 41 is sent to separation section 50, where it is separated into at least a second e-SMR-based syngas stream 51 and a process condensate 52.

[0182] A portion of the second syngas stream 51 is optionally sent to a hydrogen recovery section 60, where a hydrogen-rich stream 61 is separated and a fourth e-SMR-based syngas stream 62 is provided. A portion of the second e-SMR-based syngas stream 51 and a portion of the fourth e-SMR-based syngas stream 62 are combined to form a combined e-SMR-based syngas stream, i.e., a third e-SMR-based syngas stream 53. The hydrogen-rich stream 61 is compressed in a compressor 67 and then combined with the first reforming feed stream 1 upstream of the hydrogenation section 10, as previously described. The hydrogen recovery section 60 with recycle of the hydrogen-rich stream 61 via a compressor 67 is advantageously omitted, or at least its capacity reduced, by generating excess hydrogen in a methanol synthesis unit 220′ of the alcohol synthesis unit 220, with the hydrogenation section (10) being positioned to receive the excess hydrogen stream (not shown).

[0183] Overall, in the system shown in Figure 5, the paraffin-rich first feed to the reforming plant, and optionally an off-gas stream, are hydrogenated, desulfurized, and pre-reformed before being sent to the e-SMR. The effluent stream from the e-SMR (first e-SMR-based syngas stream) is cooled in a series of heat exchangers, including pre-reformer feed preheat, steam generation in a waste heat boiler, a feed preheater, a first feed vaporizer, and boiler feedwater preheat. Water in the effluent stream is condensed and then separated to provide a second e-SMR-based syngas stream. A portion of the e-SMR-based syngas is then used for H2 recovery for internal use, for hydrogenation and pre-reforming, or for the hydro reactor in the ATH synthesis section of the plant (Figures 1-4). The remainder of the e-SMR-based syngas is sent as a third e-SMR-based syngas stream, for example, to the alcohol synthesis unit of the plant.

[0184] The present invention has been described with reference to several embodiments and figures. However, those skilled in the art will be able to select and combine various embodiments within the scope of the present invention as defined by the appended claims. All documents cited herein are incorporated by reference in their entirety.

Claims

1. A hydrocarbon synthesis plant (200), comprising: - CO2-containing ２ First CO ２ Rich feed (201), containing H ２ First H ２ Rich feed (202), or the first CO ２ Rich feed (201) and the first H ２ a first syngas feed (209) combined with the rich feed (202); or a second syngas feed (205) to said plant comprising carbon oxides and hydrogen; - the first CO ２ Rich feed (201) and the first H ２ an alcohol synthesis unit (220) configured to receive the rich feed (202), or to receive the first syngas feed (209), or to receive the second syngas feed (205), and to provide a C2-C4 alcohols-containing effluent stream (221); an alcohol-hydrocarbon (ATH) synthesis section (230) configured to receive at least a portion of said C2-C4 alcohol-containing effluent stream (221); wherein said ATH synthesis section (230) comprises an alcohol-olefin reactor (ATO reactor) for providing an olefin-rich first product (231); said ATH synthesis section (230) is further configured to provide a C1-C4 paraffin and / or olefin-rich by-product stream (242); a reforming system (100) for reforming said by-product stream (242) rich in C1-C4 paraffins and / or olefins; wherein said reforming system (100) comprises: a first reforming feed stream (1) as said by-product stream (242) rich in C1-C4 paraffins and / or olefins, a reforming unit (40) arranged to receive said by-product stream (1, 242) rich in C1-C4 paraffins and / or olefins, to perform a steam reforming step thereon, and to provide a reformer-based syngas stream (41, 51, 53, 62); and the reforming system (100) is further configured such that the first reforming feed (1, 242) is less than 15 wt% of the first product (231) that is rich in olefins; Including, the hydrocarbon synthesis plant (200) is further configured to supply at least a portion of the reformer-based syngas stream (41, 51, 53, 62) to the inlet of the alcohol synthesis unit (220), A hydrocarbon synthesis plant (200).

2. 2. The hydrocarbon synthesis plant (200) of claim 1, further configured such that the reformer-based syngas stream (41, 51, 53, 62) is up to 50% by volume of the inlet to the alcohol synthesis unit (220), for example, from 5 to 45%, for example, from 10 to 40%.

3. 3. The hydrocarbon synthesis plant (200) of claim 1 or 2, wherein the hydrocarbon synthesis plant (200) does not include a reforming unit disposed upstream of the alcohol synthesis unit (220) to provide the first (209) or second (205) syngas feed.

4. The alcohol synthesis unit (220) - the first CO ２ Rich feed (201) and the first H ２ a methanol synthesis unit (220′) configured to receive the rich feed (202), or to receive said first syngas feed (209), or to receive said second syngas feed (205), and to provide a methanol-containing effluent stream (211); a C2-C4 alcohol synthesis unit (220'') arranged to receive said methanol-containing effluent stream (211); provided that said C2-C4 alcohol synthesis unit (220'') optionally ２ Rich feed (201), the first H ２ configured to receive a rich feed (202) and a portion of either said first syngas feed (209) and to provide said C2-C4 alcohol-containing effluent stream (221); Including, the hydrocarbon synthesis plant (200) is configured to supply the at least a portion of the reformer-based syngas stream (41, 51, 53, 62) to an inlet of the C2 to C4 alcohol synthesis unit (220''); A hydrocarbon synthesis plant (200) according to any one of claims 1 to 3.

5. The alcohol synthesis unit (220) - the first CO ２ Rich feed (201) and the first H ２ a methanol synthesis unit (220′) configured to receive the rich feed (202), or to receive said first syngas feed (209), or to receive said second syngas feed (205), and to provide a methanol-containing effluent stream (211); - the first CO ２ Rich feed (201), the first H ２ a C2 to C4 alcohol synthesis unit (220") configured to receive the rich feed (202) and a portion of either of the first syngas feed (209) and to provide a C2 to C4 alcohols-containing effluent stream (221); provided that the hydrocarbon synthesis plant (200) is optionally configured to supply at least a portion of the reformer-based syngas stream (41, 51, 53, 62) to an inlet of the C2 to C4 alcohol synthesis unit (220"); The hydrocarbon synthesis plant (200) according to any one of claims 1 to 3, comprising:

6. 6. The hydrocarbon synthesis plant (200) of claim 4 or 5, further configured to supply a portion of the reformer-based syngas stream (41, 51, 53, 62) that is 50% by volume or less to an inlet of the methanol synthesis unit (220′).

7. The alcohol synthesis unit (220) ２ Rich feed (201) and the first H ２ 2. The hydrocarbon synthesis plant (200) of claim 1, which is a C2 to C4 alcohols synthesis unit (220") configured to directly receive the rich feed (202), or to directly receive the first syngas feed (209), or to directly receive the second syngas feed (205), and provide the C2 to C4 alcohols-containing effluent stream (221).

8. 8. The hydrocarbon synthesis plant (200) of any one of claims 1 to 7, wherein the ATH synthesis section (230) comprises a first separation section configured to receive at least a portion of the first product (231) rich in olefins and to provide the by-product stream (242) rich in C1 to C4 paraffins and / or olefins.

9. 10. The hydrocarbon synthesis plant (200) of claim 8, wherein the plant is configured to recycle a portion of the by-product stream (242) rich in C1-C4 paraffins and / or olefins to the inlet of the alcohol-to-olefins (ATO) reactor.

10. The ATH synthesis section (230) further comprises an oligomerization reactor (OLI reactor) configured to receive at least a portion of the olefin-rich first product (231) and provide an oligomerized crude product stream, and a hydrogenation reactor (HYDRO reactor) configured to provide a crude product (231') comprising hydrocarbons boiling in the jet fuel range; and the ATH synthesis section (230) further comprises: a separator between the OLI reactor and the HYDRO reactor, arranged to receive at least a portion of the oligomerized crude product stream and to separate therefrom at least a portion of the by-product stream (242) rich in paraffins and / or olefins; and / or a separator downstream of said HYDRO reactor, which receives at least a portion of said crude product (231′) comprising hydrocarbons boiling in the jet fuel range and separates therefrom at least a portion of said by-product stream (242) rich in paraffins and / or olefins; The hydrocarbon synthesis plant (200) of any one of claims 1 to 9, comprising:

11. an upgrading section (240) arranged to receive at least a portion of said first product (231) rich in olefins or at least a portion of said crude product (231') comprising hydrocarbons boiling in the jet fuel range to provide a jet fuel product stream (241); further comprising: - said upgrading section (240) is arranged to provide a by-product stream (242') rich in paraffins and / or olefins; A hydrocarbon synthesis plant (200) according to any one of claims 1 to 10.

12. the plant (200) is further configured to provide one or more off-gas streams (253, 253′), a naphtha stream, or a combination thereof; and the one or more off-gas streams are either CO ２ , H ２ , C.H. ４ 12. The hydrocarbon synthesis plant (200) of any one of claims 1 to 11, wherein the one or more exhaust gas streams are rich in - said reforming system is arranged to receive at least a portion of either said one or more off-gas streams (253, 253'), a naphtha stream, or a combination thereof; and / or the C2-C4 alcohol synthesis unit (220″) of the alcohol synthesis unit (220) comprises a biocatalytic reactor arranged to receive at least a portion of the one or more off-gas streams (253, 253′), The hydrocarbon synthesis plant (200).

13. The reformer (40) in the reforming system (100) is a steam methane reformer (SMR), i.e., a tubular reformer, an electric steam methane reformer (e-SMR), an autothermal reformer (ATR), a convection-heated reformer, or a combination thereof: or The reformer (40) in the reforming system (100) - Electric steam methane reformer (e-SMR), deployed alone or with an upstream pre-reformer; or The reformer (40) in the reforming system (100) an autothermal reformer (ATR), arranged alone or with an upstream pre-reformer; A hydrocarbon synthesis plant (200) according to any one of claims 1 to 12.

14. A hydrocarbon synthesis plant (200) according to any one of claims 1 to 13, an electrolytic section, - receiving a water feed (203), i.e. steam and / or water, and optionally ２ First H ２ As the rich feed (202), ２ Second H ２ The rich feed (202′) or the first H ２ an electrolysis unit (260) arranged to provide a portion thereof as the rich feed (202); and / or - 2nd 1st CO ２ Rich feed (201′), or the CO ２ First CO ２ an electrolysis unit (250) configured to receive the rich feed (201), or a portion thereof, and to provide a CO2-enriched feed (204); - The above H-containing ２ First (202) or second H ２ a means, such as a mixing unit or junction, for combining a rich feed (202′) with said CO2-enriched feed (204) to provide said second syngas feed (205); an electrolytic section including: a pyrolysis unit configured to receive a biomass feedstock and provide a crude syngas feed, and a crude syngas purification section configured to receive said crude syngas feed and provide said second syngas feed (205); or - The above CO-containing ２ First CO ２ A portion of the rich feed (201) and the H-containing ２ First H ２ a reverse water gas shift (rWGS) unit, preferably an electric rWGS unit (e-rWGS), configured to receive a portion of the rich feed (202) and provide a rWGS syngas feed; and ２ First CO ２ Rich feed (201) and the H-containing ２ First H ２ a means, such as a mixing unit or junction, for combining with the remainder of the rich feed (202) to provide said second syngas feed (205); The hydrocarbon synthesis plant (200) further comprises:

15. The hydrocarbon synthesis plant (200) of claim 14, wherein the rWGS is configured to also receive a portion of the paraffin-rich by-product stream (242, 242').

16. 16. The hydrocarbon synthesis plant (200) according to any one of claims 1 to 15, wherein the alcohol synthesis unit (220), for example the methanol synthesis unit (220') therein, is configured to provide an excess hydrogen stream, i.e., an excess hydrogen stream from the methanol synthesis unit (220'); and the plant (200) further comprises a hydrogenation section (10) in the reforming system (100), and the hydrogenation section (10) is arranged to receive the excess hydrogen stream from the methanol synthesis unit (220').

17. Contains CO ２ First CO ２ Rich feed (201) and H-containing ２ First H ２ of the rich feed (202) or said first CO ２ Rich feed (201) and the first H ２ A process for hydrocarbon synthesis of a first syngas feed (209) in combination with a rich feed (202); or a second syngas feed (205) comprising carbon oxides and hydrogen, comprising the steps of: - providing a hydrocarbon synthesis plant (200) according to any one of claims 1 to 16; -CO ２ Rich feed (201) and H ２ feeding the rich feed (202), or the first syngas feed (209); or the second syngas feed (205) to the alcohol synthesis unit (220) and providing an effluent stream (221) comprising a C2 to C4 alcohol, for example, any one or a combination of C2 to C4 alcohols; - feeding at least a portion of the C2-C4 alcohol-containing effluent stream (221) from the alcohol synthesis unit (220) to the alcohol-hydrocarbon (ATH) synthesis section (230), i.e., the ATH synthesis section (230) comprising an alcohol-olefin reactor (ATO reactor), and providing an olefin-rich first product (231), optionally the olefin-rich first product (231) comprising at least 50% by weight of C2-C9 olefins; and further withdrawing from the ATH synthesis section (230) a by-product stream (242) rich in C1-C4 paraffins and / or olefins, such as a by-product stream (242) rich in methane, ethane, ethene (ethylene), propane, propene (propylene), butane, butene (butylene), and any combination thereof; - feeding at least a portion of said first reforming feed stream (1) as said by-product stream (242) rich in C1 to C4 paraffins and / or olefins to a reforming system (100) to carry out a reforming step in a reforming unit (reformer, 40) and provide a reformer-based syngas stream (41, 51, 53, 62), such as a first, second or third reformer-based syngas stream (41, 51, 53); wherein said first reforming feed (1, 242) is less than 15% by weight of said first product (231) rich in olefins; - feeding at least a portion of said reformer-based syngas stream (41, 51, 53, 62) to the inlet of said alcohol synthesis unit (220); The method comprising:

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