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EP-4739645-A1 - PROCESS AND PLANT FOR CONVERSION OF ALCOHOLS TO HYDROCARBONS

EP4739645A1EP 4739645 A1EP4739645 A1EP 4739645A1EP-4739645-A1

Abstract

Process and plant for producing hydrocarbons, comprising: supplying an alcohol feed stream to an alcohol-to-hydrocarbons (ATH) synthesis section, said ATH synthesis section comprising an alcohol-to-olefins (ATO) section, said ATO section comprising an alcohol-to-olefin reactor (ATO) reactor; said alcohol feed stream being any of: i) a combination of a C2-C8 alcohol stream and a methanol (MeOH) stream; ii) a C2-C8 alcohol stream and a MeOH stream being supplied separately; iii) a combination thereof; supplying said alcohol feed stream to the ATO reactor, the ATO reactor comprising an adiabatic fixed bed reaction zone having a conversion catalyst comprising a zeolite with a framework having a ring pore structure, said ring pore structure being a unidi-mensional (1D) pore structure; and providing a first product rich in olefins as said hydrocarbons; wherein the weight ratio of the C2-C8 alcohol to methanol (MeOH) in any of said alcohol feed streams is in the range 0.30-6.0.

Inventors

  • SCHJØDT, NIELS CHRISTIAN
  • PEDERSEN, HENRIK GULDBERG
  • Burn, Jeremy Neil
  • JOENSEN, FINN
  • TAARNING, ESBEN
  • BROGAARD, Rasmus Yding

Assignees

  • Topsoe A/S

Dates

Publication Date
20260513
Application Date
20240628

Claims (17)

  1. 1. A process for producing hydrocarbons, comprising: - supplying an alcohol feed stream to an alcohol-to-hydrocarbons (ATH) synthesis section, said ATH synthesis section comprising an alcohol-to-olefins (ATO) section, said ATO section comprising an alcohol-to-olefin (ATO) reactor; said alcohol feed stream being any of: i) a combination of a C2-C8 alcohol stream and a methanol (MeOH) stream; ii) a C2-C8 alcohol stream and a MeOH stream being supplied separately; iii) a combination thereof; - supplying said alcohol feed stream to the ATO reactor, the ATO reactor comprising an adiabatic fixed bed reaction zone having a conversion catalyst comprising a zeolite with a framework having a 10-ring pore structure, said 10-ring pore structure being a unidimensional (1 D) pore structure; and providing a first product rich in olefins as said hydrocarbons; wherein the weight ratio of the C2-C8 alcohol to methanol (MeOH) in any of said alcohol feed streams is in the range 0.30-6.0.
  2. 2. Process according to claim 1 , wherein said C2-C8 alcohol is a C2-C4 alcohol.
  3. 3. Process according to any of claims 1-2, wherein said first product rich in olefins comprises: at least 20 vol% C4-olefins; and at least 25 vol% C5+ hydrocarbons of which at least 20 vol% are C5-C8 olefins.
  4. 4. Process according to any of claims 1-3, wherein the C2-C8 alcohol is ethanol (EtOH) and the weight ratio of EtOH to MeOH is 0.36-5.75, such as 0.43-4.55.
  5. 5. Process according to any of claims 1-4, wherein the C2-C8 alcohol is ethanol (EtOH) and the weight ratio of EtOH to MeOH is 0.36-0.62, such as 0.36-0.48.
  6. 6. Process according to any of claims 1-5, wherein the alcohol feed stream is said C2- C8 alcohol stream and a MeOH stream being supplied separately, and wherein the C2- C8 alcohol stream and the MeOH stream are supplied to the ATO reactor at distinct feeding points, by feeding the C2-C8 alcohol stream at a position downstream the feeding point of said MeOH stream.
  7. 7. Process according to claim 6, wherein the ATO reactor is provided with at least two adiabatic fixed bed reaction zones as a first adiabatic fixed bed reaction zone and a subsequent adiabatic fixed bed reaction zone, wherein the first adiabatic fixed bed reaction zone e.g. an upper bed, is supplied with said MeOH stream, and the subsequent adiabatic fixed bed reaction zone provided downstream is supplied with said C2-C8 alcohol stream.
  8. 8. Process according to claim 7, wherein the subsequent adiabatic fixed bed reaction zone comprises one or more beds, and any of said beds is supplied with said C2-C8 alcohol stream; for instance, a first C2-C8 alcohol stream is supplied to a first bed of said subsequent adiabatic fixed bed reaction zone, and a second C2-C8 alcohol stream is supplied to a downstream bed of said subsequent adiabatic fixed bed reaction zone.
  9. 9. Process according to any of claims 7-8, wherein a raw first product rich in olefins is withdrawn from the first adiabatic fixed bed reaction zone and combined with the C2- C8 alcohol stream prior to being supplied to the subsequent adiabatic fixed bed reaction zone.
  10. 10. Process according to any of claims 1-9, wherein: - the inlet temperature of the alcohol feed stream to the ATO reactor is 275°C or higher, and the outlet temperature of said first product rich in olefins is 475°C or lower; and/or - the pressure of the ATO is at least 10 barg, such as 10-120 barg, e.g. 15-120 barg, 20-100 barg, or 20-80 barg; and/or - said 1-D pore structure of the conversion catalyst is any of *MRE (ZSM-48), MTT (ZSM-23), TON (ZSM-22), or combinations thereof.
  11. 11 . Process according to any of claims 1-10, wherein the process further comprises a prior step of: - supplying any of a biomass feed, an industrial off-gas containing carbon oxides, a municipal solid waste feed, or combinations thereof, to a fermentation reactor for producing said C2-C8 alcohol stream, preferably as a C2-alcohol stream (EtOH stream), the fermentation reactor further producing a CO2 byproduct stream; wherein the process further comprises: - withdrawing at least a portion of said industrial off-gas containing carbon oxides, suitably a CC>2-stream thereof; or withdrawing at least a portion of said CO2 byproduct stream; - providing a H2-stream, suitably by supplying a water feedstock, i.e. water or steam, to an electrolysis unit for producing an Ch-stream and said H2-stream; - supplying the CCh-stream and/or said CO2 byproduct stream, and the H2-stream, optionally after mixing, to a methanol synthesis section (MeOH section) for producing said MeOH stream.
  12. 12. Process according to any of claims 1-11 , wherein the process further comprises: - withdrawing from said ATH synthesis section, optionally from said MeOH section, a by-product stream rich in C1-C4 paraffins and/or olefins, such as any of: methane, ethane, ethene (ethylene), propane, propene (propylene), butane, butene (butylene), and combinations thereof; - supplying at least a portion of said by-product stream rich in C1-C4 paraffins and/or olefins, to any of: a reforming system comprising a reforming unit (reformer), performing a reforming step in said reforming unit, and providing a reformer-based syngas stream; a gasification section comprising a gasification unit (gasifier), performing a gasification step in said gasification unit, and providing a gasifier-based syngas stream; - supplying at least a portion of said reformer-based or gasifier-based syngas stream to the inlet of the methanol synthesis section (MeOH section).
  13. 13. Process according claim 12, wherein said reforming unit is an electrically heated steam methane reformer (e-SMR); or wherein said reforming unit is an autothermal reformer (ATR) and at least a portion of said 02-stream is supplied to said ATR or said gasification unit (gasifier).
  14. 14. Process according to any of claims 11-13, wherein the process further comprising: - said fermentation reactor producing a bio-waste stream comprising any of mash and lignin, and supplying at least a portion thereof to said gasification unit.
  15. 15. Process according to any of claims 11-14, wherein at least a portion of the CO2- stream and/or said CO2 byproduct stream is electrolyzed together with steam, i.e. coelectrolysis, thereby providing a stream comprising CO and CO2; and mixing it with said H2-stream, thereby providing a syngas enriched in CO.
  16. 16. Process according to any of claims 1-15, wherein the ATO section comprises a first product separation unit; wherein the ATH synthesis section comprises: - an oligomerization (OLI) section, said OLI section comprising an OLI reactor, optionally, a second product separation unit; - a fractionation section; - a hydroprocessing section, suitably a hydrogenation section; and the process further comprising: - supplying said first product rich in olefins from the ATO reactor to said first product separation unit, and withdrawing therefrom at least a first recycle overhead stream and a first raw hydrocarbon product stream; - supplying said first product rich in olefins from the ATO reactor and/or said first raw hydrocarbon product stream to the OLI reactor of said OLI section and further to said fractionation section; and withdrawing from said fractionation section: at least an intermediate naphtha stream and an intermediate jet fuel stream, optionally an intermediate diesel stream, optionally also a by-product stream rich in C1 -C4 paraffins and/or olefins, such as any of: methane, ethane, ethene (ethylene), propane, propene (propylene), butane, butene (butylene), and combinations thereof; - supplying at least said intermediate jet fuel stream to said hydroprocessing section, suitably to said hydrogenation section, and withdrawing therefrom a jet fuel product.
  17. 17. Plant for carrying out the process according to any of claims 1-16; comprising: - an alcohol-to-hydrocarbons (ATH) synthesis section arranged to receive an alcohol feed stream, said ATH-synthesis section comprising an alcohol-to-olefins (ATO) section, said ATO section comprising an alcohol-to-olefin (ATO) reactor; said alcohol feed stream being any of : i) a combination of a C2-C8 alcohol stream and a methanol (MeOH) stream; ii) a C2-C8 alcohol stream and a MeOH stream being supplied separately; iii) a combination thereof; in which the weight ratio of the C2-C8 alcohol to methanol (MeOH) in any of said alcohol feed streams is in the range 0.30-6.0; - the ATO reactor being arranged to receive said alcohol feed stream and provide a first product rich in olefins as said hydrocarbons; the ATO reactor comprising an adiabatic fixed bed reaction zone having a conversion catalyst comprising a zeolite with a framework having a 10-ring pore structure, said 10-ring pore structure being a unidimensional (1 D) pore structure; and providing a first product rich in olefins as said hy- drocarbons; - optionally, the alcohol feed stream is provided as a separate C2-C8 alcohol stream and a separate MeOH stream, and the ATO reactor is arranged to receive the C2-C8 alcohol stream and the MeOH stream at distinct feeding points by the ATO reactor being arranged to receive the C2-C8 alcohol stream at a position downstream the feeding point of said MeOH stream.

Description

Title: Process and plant for conversion of alcohols to hydrocarbons FIELD OF THE INVENTION The present invention relates to the conversion of oxygenates to hydrocarbons, such as the conversion of methanol or ethanol into hydrocarbons such as a jet fuel, suitably as sustainable aviation fuel (SAF). FIELD OF THE INVENTION The production of hydrocarbons in the transportation fuel range such as jet fuel is currently made from fossil sources. Recent concepts to produce jet fuel include converting methanol to olefins in a methanol-to-olefins (MTO) step, optionally followed by further oligomerization in an oligomerization step and a conditioning step including hydrogenation to convert olefins to paraffins and finally a fractionation step. For instance, applicant’s WO2022063992 discloses a process for producing hydrocarbons boiling in the jet fuel boiling range, particularly as sustainable aviation fuel (SAF), as well as high grade propylene as a chemical product. It is also known that ethanol can be converted to jet fuel in a similar way, yet this is not in current industrial use. Related prior art is also disclosed in WO 2009063177 A1 . SUMMARY OF THE INVENTION It would be desirable to be able to convert methanol (MeOH) and higher alcohols such as ethanol (EtOH) in connection with methanol-to-hydrocarbon (MTH) reactions or more generally alcohol-to-hydrocarbon (ATH) reactions, for instance alcohol-to-olefin (ATO) reactions, into synthetic fuels such as jet fuel and chemicals such as propylene (C3= or interchangeably propene). However, using EtOH as feed for an ATO reaction poses significant problems, as outlined below. Using pure EtOH as feed instead of pure MeOH for the MTH reactions has at least two inherent problems arising from the fact that EtOH loses water and forms ethylene very fast in the ATO reactor: 1) ethylene is the least reactive of all the olefins in the ATO reaction; 2) EtOH (C2-alcohol) dehydration to ethylene is an endothermic reaction by approximately 47 kJ/mol ethylene, and by approximately 35 and 33 kJ/mol for, respectively, propanol (C3-alcohol) and butanol (C4-alcohol) dehydration, as well as approximately 32 kJ/mol for C8-alcohol dehydration to 1 -octene, which in an industrial reactor causes a sudden and steep drop in the inlet temperature of the ATO reactor. If not compensated for by increasing the inlet temperature to the ATO reactor, it can cause the ATO reaction to extinguish. On the other hand, when the inlet temperature to the ATO reactor is raised, it moves the ATO product distribution towards lighter hydrocarbons, which will decrease the overall hydrocarbon product value, as there is less production of the desired heavier hydrocarbons, such as hydrocarbons in the jet fuel range. It would therefore be desirable to be able to overcome the above problems. More generally, it would be desirable to provide a simple and efficient process and plant for converting methanol and higher alcohols such as EtOH to hydrocarbons, such as hydrocarbons boiling in the jet fuel range. Accordingly, in a first aspect, the invention is a process for producing hydrocarbons, comprising: - supplying an alcohol feed stream to an alcohol-to-hydrocarbons (ATH) synthesis section, said ATH synthesis section comprising an alcohol-to-olefins (ATO) section, said ATO section comprising an alcohol-to-olefin reactor (ATO) reactor; said alcohol feed stream being any of: i) a combination of a C2-C8 alcohol stream and a methanol (MeOH) stream; ii) a C2-C8 alcohol stream and a MeOH stream being supplied separately; iii) a combination thereof, i.e. a combination of i and ii; - supplying said alcohol feed stream to the ATO reactor, the ATO reactor comprising an adiabatic fixed bed reaction zone having a conversion catalyst comprising a zeolite with a framework having a 10-ring pore structure, said 10-ring pore structure being a unidimensional (1 D) pore structure; and providing a first product rich in olefins as said hydrocarbons; wherein the weight ratio of the C2-C8 alcohol to methanol (MeOH) in any of said alcohol feed streams is in the range 0.30-6.0. In an embodiment, said C2-C8 alcohol is a C2-C4 alcohol. Hence, the present invention shows how to combine methanol and higher alcohols (C2-C8 alcohols), such as ethanol, as feed to produce hydrocarbons such as jet fuel. It is shown that there is an unexpected beneficial effect of limiting the EtOH/MeOH ratio to a certain range. Furthermore, and in connection thereto, the inherent problem of temperature drop associated with ethanol dehydration to ethylene is solved by, in an embodiment, introducing ethanol to the ATO reactor downstream the introduction of the methanol feed in such way as to minimize the inlet temperature and/or reduce the recy- cle-to-makeup ratio and to improve the yield of higher (C5+) olefins, and advantageously also the yield of C4-olefins (C4=). Also in connection thereto, the production of paraffins, isoparaffins and naphthenes (P/l/N) is at the