Efficient use of heat in an electrolytic methanol plant

Abstract

This invention provides a methanol plant and a method for producing methanol. A first SOE (Self-Oxygenation Electrolysis) section is arranged to receive a carbon dioxide-rich feed and electrolyze it into a carbon monoxide-rich stream. A methanol circuit is arranged to receive at least a portion of the carbon monoxide-rich stream and a hydrogen-rich stream, and convert them into a crude methanol stream. A first H2O-rich stream is converted into a first vapor stream using heat from the electrolysis process in the first SOE section. The first vapor stream is used as heat for distilling the crude methanol stream in a methanol distillation section.

Description

Technical Field

[0001] This invention relates to a methanol plant and a method for producing methanol using said plant. A first SOE (Sequencing Electrolysis) section is arranged to receive a carbon dioxide-rich feed and electrolyze it into a carbon monoxide-rich stream. A methanol circuit is arranged to receive at least a portion of the carbon monoxide-rich stream and a hydrogen-rich stream, and convert them into a crude methanol stream. A first H₂O-rich stream is converted into a first vapor stream using heat from the electrolysis process in the first SOE section. The first vapor stream is used as heat for distilling the crude methanol stream in a methanol distillation section. Background Technology

[0002] People are making ongoing efforts to replace fossil fuels and move towards the sustainable production and storage of energy and chemicals. A key contribution driving these efforts is Power-to-X (PtX), which involves systems and methods that enable the conversion, storage, and re-conversion of electricity to store energy in the form of synthetic alcohols, synthetic fuels, or alternative chemicals such as natural gas.

[0003] One way to utilize electricity is by electrolyzing water to produce H2. It is known that the H2 and CO2 are then combined into a mixed stream, which is then converted into syngas rich in CO and H2, which can be further converted into valuable products such as alcohols (including methanol). However, the current production of syngas from H2 and CO2 for alcohol synthesis is generally inefficient and energy-intensive.

[0004] Recent developments have disclosed an electrolytic methanol (e-methanol) unit that combines an H2-rich stream from H2O electrolysis with a CO-rich stream from CO2 electrolysis to provide a syngas stream, which is then used for methanol synthesis.

[0005] However, there is a general need to further develop such devices to make them feasible for sustainable production and reduce energy consumption, thereby reducing the CO2 footprint of such systems and methods. A particular objective is to effectively utilize the heat generated in one section of the device in other sections. Summary of the Invention

[0006] The inventors have discovered that the heat generated during the electrolysis process can be advantageously used for methanol distillation.

[0007] Therefore, a methanol apparatus is provided, the methanol apparatus comprising: - Carbon dioxide-rich feedstock; - First rich H2O flow; - First solid oxide electrolysis (SOE) section; - Second electrolysis section; - Methanol circuit; - Methanol distillation section; The first SOE section is configured to receive carbon dioxide-rich feed and electrolyze it during the first electrolysis process to output carbon monoxide-rich stream and oxygen-rich stream (12). The second electrolysis section is configured to output a hydrogen-rich stream. The methanol circuit is configured to receive at least a portion of a carbon monoxide-rich stream and at least a portion of a hydrogen-rich stream, and convert them into a crude methanol stream. The methanol distillation section is configured to receive a crude methanol stream from the methanol circuit and distill it to output a purified methanol product stream. The methanol unit is also arranged to receive a first H2O-rich stream and convert it into a first vapor stream by means of heat from the first electrolysis process in the first SOE section. Furthermore, the methanol distillation section is arranged to receive the first vapor stream and use it as heat for the crude methanol stream.

[0008] The present invention also provides a method for producing methanol in the apparatus described herein, the method comprising the following steps: - A carbon dioxide-rich feed is supplied to the first SOE section and electrolyzed into a carbon monoxide-rich stream and an oxygen-rich stream during the first electrolysis process; - Output hydrogen-rich stream from the second electrolysis section; - At least a portion of the carbon monoxide-rich stream and at least a portion of the hydrogen-rich stream are supplied to the methanol circuit and converted into a crude methanol stream; - The crude methanol stream from the methanol loop is supplied to the methanol distillation section and distilled to output a purified methanol product stream; - By transferring heat from the first electrolysis process in the first SOE section, the first H2O-rich stream is converted into a first steam stream; - The first steam stream is supplied to the methanol distillation section and used as heat for the distillation of the crude methanol stream.

[0009] Further details of the systems and methods for producing synthetic gas streams, as well as related apparatus, will be described in the following detailed description of the invention, drawings, and claims. Attached Figure Description

[0010] Figure 1 A schematic overview of a methanol plant according to the first aspect is shown.

[0011] Figure 2 Showing Figure 1 A more detailed schematic overview of the methanol plant. Invention Details

[0013] Unless otherwise stated, all gas percentages given are by volume. In this document, the terms "syngas" and "synthesis gas" are used interchangeably.

[0014] A methanol apparatus is provided. The methanol apparatus includes: - Carbon dioxide-rich feedstock; - First rich H2O flow; - First solid oxide electrolysis (SOE) section; - Second electrolysis section; - Methanol circuit; and - Methanol distillation section; In summary, the conversion of CO2 to methanol occurs in this device.

[0015] First SOE Section

[0016] The first solid oxide electrolysis (SOE) section is configured to receive a carbon dioxide-rich feed and electrolyze it into a carbon monoxide-rich stream.

[0017] A carbon dioxide-rich feed is defined as being rich in carbon dioxide, for example, containing more than 97 vol%, preferably more than 98 vol% or 99 vol%. A carbon dioxide-rich stream contains carbon dioxide from external sources, such as from biogas upgrading or fossil fuel-based syngas (syngas) plants, or from biomass and / or fossil fuel-based power plants, or from cement production or from fermentation processes such as ethanol production.

[0018] The first solid oxide electrolysis (SOE) section includes a solid oxide electrolyzer (SOEC), such as one or more SOECs arranged in an SOEC stack. This solid oxide electrolyzer is a solid oxide fuel cell (SOFC) operating in reverse mode, which uses solid oxide or ceramic electrolytes to generate a carbon monoxide-rich stream.

[0019] Specifically for the first SOE stage, CO2 is directed to the fuel side of the battery by applying an electric current, and excess oxygen is delivered to the oxygen side of the battery (e.g., the anode side) to electrolyze CO2 into CO. Therefore, the first SOE stage provides a carbon monoxide-rich stream from the fuel side of the battery and a first oxygen-rich stream from the oxygen side. The carbon monoxide-rich stream provided by the first SOE stage contains a mixture of CO and CO2, wherein the CO content is preferably 20%-80%.

[0020] Optionally, a purge gas flow, such as air or nitrogen, is directed to the oxygen side to purge it. Purge the oxygen side of the SOE has two advantages: i) reducing the oxygen concentration within the cell and the associated corrosive effects; and ii) providing a means for powering the first SOE, since the operation is endothermic.

[0021] In some embodiments, a carbon monoxide-rich stream (containing a mixture of CO and CO2) is arranged to be directed to a separation unit, such as a pressure swing adsorption (PSA) unit, a temperature swing adsorption (TSA) membrane separation unit, a cryogenic separation unit, or a liquid scrubbing technology unit (e.g., scrubbing using N-methyldiethanolamine (MDEA)). The purpose of the separation unit is to produce a further enriched carbon monoxide stream and a carbon dioxide-rich balance stream. In some embodiments, the balance stream may be recycled to the carbon monoxide-rich stream arranged to be supplied to one or more separation units and / or recycled to the inlet of a first SOE stage for further conversion, optionally mixed with a carbon dioxide-rich feed. In this way, the exact composition of the carbon monoxide-rich stream can vary. In all embodiments, the carbon monoxide-rich stream can be a further enriched carbon monoxide stream.

[0022] In an alternative preferred embodiment, CO2 electrolysis is carried out in a single-through operation, meaning the SOE section is a single-pass electrolysis unit. The term "single-pass" means that CO2 recycling is not required. Compared to conventional systems used for CO2 electrolysis, this eliminates the need for a recirculation compressor, and consequently, valves, piping, and control systems. This results in savings on associated operating costs, such as the electricity required for the compressor and the maintenance of the recirculation compressor and other equipment (e.g., valves and piping). Furthermore, the need for a pressure swing adsorption (PSA) unit is eliminated, significantly simplifying the systems, processes, and apparatus for producing syngas for further conversion. Additionally, the single-pass SOE section for CO2 electrolysis can operate with partial conversion, mitigating the risk of carbon buildup within the SOE section. In an alternative embodiment, a portion of the carbon monoxide-rich stream can be recycled to the inlet of the first SOE section for further conversion, optionally mixed with a carbon dioxide-rich feed.

[0023] In some embodiments, the system further includes one or more heating units arranged to heat the carbon dioxide-rich feed and / or optional purge gas flow. Preferably, the operating temperature of the one or more heating units is at least 50°C above the operating temperature of the first SOE section, and more preferably at least the operating temperature of the first SOE section. In this way, heat can be supplied to the SOE section.

[0024] In a preferred embodiment, the first solid oxide electrolysis (SOE) stage operates within a temperature range of 500-900°C, preferably 700-800°C. Operating at these higher operating temperatures offers the advantage of higher conversion efficiency compared to low-temperature electrolysis due to the favorable thermodynamics and kinetics. Furthermore, high-temperature operation results in lower operating costs due to lower cell voltage and lower capital expenditure due to higher current density.

[0025] Regardless of the implementation scheme, the first SOE section is configured to receive a carbon dioxide-rich feed and provide a carbon monoxide-rich stream, and preferably a first oxygen-rich stream.

[0026] First Richest H 2 O-flow and heat exchange

[0027] The first H2O-rich stream can be water-rich, for example, containing more than 90% water, preferably 99% water. Alternatively, the H2O-rich stream can contain a first portion of steam. Preferably, the H2O-rich stream has high purity, for example, 99 vol% H2O. In an embodiment, the first H2O-rich stream can be provided by a water treatment unit. Examples of the first H2O-rich stream composition include: DMW purity (mass) The pH value at 25°C is 6-7. Specific conductivity (μS / cm) at 25°C < 0.2. Iron (Fe), total (mg / kg) < 0.02, Total copper (Cu), total (mg / kg) < 0.003, Sodium (Na) (mg / kg) < 0.01 KMnO4 consumption Mn(VII) → Mn(II), calculated as KMnO4 (mg / kg) < 3, Oils and fats (mg / kg) < 1.

[0028] The temperature of the first H2O-rich stream can be between 0 and 200°C. Preferably, the first H2O-rich stream is a water-rich stream with a temperature between 30 and 130°C. The pressure of the first H2O-rich stream can be 1-20 bar g, preferably 2-5 bar g.

[0029] The methanol unit is also configured to receive a first H2O-rich stream and convert it into a first vapor stream by means of the heat from the electrolysis process in the first SOE section.

[0030] The conversion of the first H2O-rich stream to the first vapor stream can be achieved through direct heating or indirect heating. In this paper, direct heating refers to the transfer of heat directly from the heat source to the stream to be heated through the heat transfer wall; while indirect heating refers to the transfer of heat from the heat source through an intermediate heat transfer medium, which transfers heat to the stream to be heated through the heat transfer wall.

[0031] In one aspect, the methanol plant further includes a heat exchanger section comprising one or more heat exchangers. In one embodiment, the heat exchanger section includes a first heat exchanger and a second heat exchanger. The first and second heat exchangers can be independently selected from two-tube heat exchangers, shell-and-tube heat exchangers, plate heat exchangers, or cross-flow heat exchangers. Preferably, in some embodiments, the first and second heat exchangers are shell-and-tube heat exchangers. The first and second heat exchangers can also be cross-flow heat exchangers.

[0032] Fluid flow within a heat exchanger can be arranged in a co-current, counter-current, or cross-current configuration. In a preferred embodiment, the fluid flow is arranged in a counter-current configuration. In some embodiments, counter-current flow is advantageous where heat transfer primarily results in a temperature increase, such as providing a heated or evaporating H2O-rich flow. Counter-current flow allows for optimized heat transfer efficiency (heat transfer per unit mass) because the average temperature difference along any unit length is higher compared to alternative flow arrangements. In a more preferred embodiment, the fluid flow is arranged in a cross-current configuration. Cross-current flow is particularly advantageous in embodiments where heat transfer primarily results in a phase change (e.g., a transition from water to steam).

[0033] In embodiments where at least a portion of the carbon monoxide-rich flow and at least a portion of the first oxygen-rich flow are both arranged to transfer heat, it is preferred that portions i) and ii) are arranged to have the same flow arrangement.

[0034] In one aspect, the heat exchanger section can be arranged to receive a carbon monoxide-rich stream and a first H2O-rich stream, transfer heat from the carbon monoxide-rich stream to the first H2O-rich stream, and output a first steam stream and a cooled carbon monoxide-rich stream.

[0035] The heat exchanger section can also be arranged to transfer heat from the first oxygen-enriched stream to the first H2O-enriched stream and further output a cooled first oxygen-enriched stream. In this way, heat transfer to the first H2O-enriched stream can be optimized by selecting to transfer heat from the carbon monoxide-enriched stream and / or the first oxygen-enriched stream.

[0036] Allowing thermal communication between at least a portion of the carbon monoxide-rich stream and at least a portion of the first H₂O-rich feed has the advantage of further cooling the carbon monoxide-rich stream, which is desirable when syngas is formed from the cooled carbon monoxide-rich stream. In this way, providing a cooled carbon monoxide-rich stream can eliminate or reduce the need for a separate cooling system, or allow for a reduction in the capacity of such a cooling system.

[0037] Appropriately, the first H2O-rich stream is external to the unit (i.e., the unit's feed). Alternatively, or furthermore, the first H2O-rich stream is at least a portion of the tail gas from the methanol loop and / or the methanol distillation section.

[0038] According to the present invention, the heat exchange section of the methanol unit may further include a steam drum, which is arranged to vaporize liquid water into steam by means of heat from at least one of a carbon monoxide-rich stream and / or a first oxygen-rich stream.

[0039] Second Electrolysis Section

[0040] The second electrolysis section is configured to output a hydrogen-rich stream.

[0041] In one aspect, the second electrolysis section is a second solid oxide electrolysis (SOE) section. According to this aspect, the methanol unit also includes a second H2O-rich stream, wherein the second solid oxide electrolysis (SOE) section is arranged to receive at least a portion of the second H2O-rich stream and electrolyze it into the hydrogen-rich stream.

[0042] The second electrolysis section can also be configured to provide a second oxygen-enriched flow.

[0043] The second SOE stage employs a solid oxide or ceramic electrolyte to generate a hydrogen-rich stream. More specifically, a second H2O-rich stream is directed to the fuel side of the battery by applying an electric current, and excess oxygen is supplied to the oxygen side of the battery (e.g., the anode side) to electrolyze H2O into hydrogen. Optionally, a purge stream, such as air or nitrogen, is directed to the oxygen side to purge it. This results in the second SOE stage providing a hydrogen-rich stream from the fuel side of the battery and a second oxygen-rich stream from the oxygen side. The hydrogen-rich stream provided by the second electrolysis stage appropriately contains H2 and vapor, wherein the H2 content is between 20-100%, preferably 40-80%.

[0044] In some embodiments, the system further includes an external second H2O-rich stream (i.e., a second H2O-rich feed), which may be in the form of a second steam stream arranged to be supplied to the second solid oxide electrolysis (SOE) section. The external second steam stream can be provided by a water treatment system, for example, H2O with a high purity such as 99.99%. This external second steam stream can have a temperature of 100-210°C, preferably 130-160°C, and a pressure of 1-19 bar g, preferably 1-4 bar g, at the SOE inlet.

[0045] In some embodiments, the system further includes one or more heating units arranged to heat an external second steam stream and / or optional purge gas stream. Preferably, the operating temperature of the one or more heating units is at least 50°C above the operating temperature of the second electrolysis section, and more preferably at least the operating temperature of the second electrolysis section. In this way, heat can be supplied to the second electrolysis section.

[0046] In a preferred embodiment, when the second electrolysis section is a second solid oxide electrolysis (SOE) section, it operates within a temperature range of 500-900°C, preferably 700-800°C. In some embodiments, the system further includes one or more heating units arranged to provide additional heat to the second SOE section during operation. The one or more heating units may include feed-effect exchangers and / or electric heaters.

[0047] Methanol circuit

[0048] The methanol circuit (also known as the methanol synthesis section) is configured to receive at least a portion of the carbon monoxide-rich stream and at least a portion of the hydrogen-rich stream, and convert them into a crude methanol stream. Exhaust gas is also generated at the same time.

[0049] The methanol synthesis reactor in the methanol circuit can carry out the following two reactions:

[0050] This process can be carried out, for example, by feeding a combined stream to a boiling water reactor, where at least a portion of the gas in the combined stream is converted to methanol, followed by condensation and separation of the methanol in the liquid phase, which is contained within the methanol stream. This process generates a tail gas stream. The tail gas stream from the methanol synthesis section typically contains: 85-90% H2, 5-10% CO2, and 0-3% CO.

[0051] The crude methanol product stream contains a major component of methanol, for example, 60-65% methanol and 35-40% H2O by weight. Other minor components of the stream include, but are not limited to, higher alcohols, ketones, aldehydes, dimethyl ether (DME), organic acids, and dissolved gases.

[0052] To achieve optimized yields in methanol production, the stoichiometry of H2, CO, and CO2 needs to be considered. In a preferred embodiment, the stoichiometry of H2, CO, and CO2 in the combined stream (syngas stream) falls within a range such that the combined stream has a modulus between 1.8 and 2.2, preferably between 1.9 and 2.1, where the modulus is defined according to the molar content as:

[0053] The modulus of the syngas flow can be adjusted by adding a (further) hydrogen-rich flow, which is optionally arranged to mix with the syngas flow. The hydrogen-rich flow can be provided by an external hydrogen supply.

[0054] Methanol distillation section

[0055] The methanol distillation section is configured to receive the crude methanol stream from the methanol loop and distill it to output a purified methanol product stream.

[0056] The distillation section is configured to upgrade the crude methanol stream into a purified methanol product stream of the desired grade, such as >95%, >98%, or >99% methanol.

[0057] The methanol distillation section is configured to receive the first vapor stream and use it as heat for the distillation of the crude methanol stream. In this way, efficient utilization of heat is ensured elsewhere in the unit.

[0058] method

[0059] A method for producing methanol in the apparatus described herein is also provided. The method includes the following steps: - The carbon dioxide-rich feed is fed to the first SOE section and electrolyzed into a carbon monoxide-rich stream; - Output hydrogen-rich stream from the second electrolysis section; - At least a portion of the carbon monoxide-rich stream and at least a portion of the hydrogen-rich stream are supplied to the methanol circuit and converted into a crude methanol stream; - The crude methanol stream from the methanol loop is supplied to the methanol distillation section for distillation, thereby outputting a purified methanol product stream; - Using the heat from the electrolysis process in the first SOE section, the first H2O-rich stream is converted into a first steam stream; - The first steam stream is supplied to the methanol distillation section and used as heat for the distillation of the crude methanol stream.

[0060] According to the method of the present invention, heat transfer from the first electrolysis process can be achieved by transferring heat from at least a portion of the carbon monoxide-rich stream (11) and / or at least a portion of the first oxygen-rich stream (12).

[0061] Appropriately, i) at least a portion of the carbon monoxide-enriched stream and / or ii) at least a portion of the first oxygen-enriched stream, the temperature of at least one of them is 500- Within the range of C, and i) at least a portion of the carbon monoxide-rich stream and / or ii) at least a portion of the first oxygen-rich stream, the pressure of at least one of them is in the range of 0-3 bar g.

[0062] In one aspect, the first solid oxide electrolysis (SOE) section is at 500- C, preferably 700- The second electrolysis section operates within a temperature range of C. It is a solid oxide electrolysis (SOE) section, which operates at 500- C, preferably 700- Operate within the temperature range of C. The temperature of the first steam stream is appropriately between 100 – Between C, 150 is preferred – C, and the pressure of the first steam stream (13) is between 3.5 and 9 bar g. Detailed Implementation

[0063] Figure 1 A methanol unit (100) including the following components is shown: - Carbon dioxide-rich feed (1); - First rich H2O flow (2); - First solid oxide electrolysis (SOE) section (10); - Second electrolysis section (20); - Methanol circuit (30); - Methanol distillation section (40); The first SOE section (10) receives a carbon dioxide-rich feed (1) and electrolyzes it into a carbon monoxide-rich stream (11). The second electrolysis section (20) outputs a hydrogen-rich stream (21). The methanol circuit (30) receives at least a portion of the carbon monoxide-rich stream (11) and at least a portion of the hydrogen-rich stream (21) and converts them into a crude methanol stream (31). The methanol distillation section (40) receives the crude methanol stream (31) from the methanol circuit (30) and distills it to output a purified methanol product stream (41). The first H2O-rich stream (2) is converted into a first vapor stream (13) using heat from the electrolysis process in the first SOE section (10). The methanol distillation section (40) receives the first vapor stream (13) and uses it as heat for distilling the crude methanol stream (31).

[0064] Figure 2 A more complete embodiment is shown, in which the methanol unit further includes a heat exchanger section (50). A first SOE section (10) receives a carbon dioxide-rich feed (1) and electrolyzes it into a carbon monoxide-rich stream (11) and a first oxygen-rich stream (12). The heat exchanger section (50) transfers heat from the first oxygen-rich stream (12) to the first H2O-rich stream (2). A first steam stream (13), a cooled carbon monoxide-rich stream (11'), and a cooled first oxygen-rich stream (12') are output from the heat exchanger section (50). Figure 2 As shown, the cooled carbon monoxide-rich stream (11') and at least a portion of the hydrogen-rich stream (21) are supplied to the methanol circuit (30) and converted into a crude methanol stream (31), which is then processed according to... Figure 1 The use of.

[0065] Example

[0066] The uses of the invention are illustrated below. It can reduce the external heat input required for the distillation section of a 300 MTPD methanol unit based on CO2 and hydrogen feedstocks. As can be seen from the table, the steam generated in the CO2 electrolysis section accounts for 7.5% of the total steam required to obtain AA-grade methanol product from distillation.

[0067]

Claims

1. A methanol apparatus (100), the methanol apparatus comprising: - Carbon dioxide-rich feed (1); - First rich H2O flow (2); - First solid oxide electrolysis (SOE) section (10); - Second electrolysis section (20); - Methanol circuit (30); - Methanol distillation section (40); The first SOE section (10) is arranged to receive carbon dioxide-rich feed (1) and electrolyze it in the first electrolysis process to output carbon monoxide-rich stream (11) and oxygen-rich stream (12). The second electrolysis section (20) is configured to output a hydrogen-rich stream (21); The methanol circuit (30) is arranged to receive at least a portion of the carbon monoxide-rich stream (11, 11') and at least a portion of the hydrogen-rich stream (21), and convert them into a crude methanol stream (31). The methanol distillation section (40) is arranged to receive a crude methanol stream (31) from the methanol circuit (30) and distill it to output a purified methanol product stream (41). The methanol unit (100) is also arranged to receive a first H2O-rich stream (2) and convert it into a first vapor stream (13) by means of heat from the first electrolysis process in the first SOE section (10). And the methanol distillation section (40) is arranged to receive the first vapor stream (13) and use it as heat for distillation of the crude methanol stream (31).

2. The methanol apparatus (100) according to claim 1 further includes a heat exchanger section (50) arranged to receive a carbon monoxide-rich stream (11) and a first H2O-rich stream (2), transfer heat from the carbon monoxide-rich stream (11) to the first H2O-rich stream (2), and output a first steam stream (13) and a cooled carbon monoxide-rich stream (11').

3. The methanol apparatus (100) according to any of the preceding claims, wherein the second electrolysis section (20) is a second solid oxide electrolysis (SOE) section, the methanol apparatus (100) further comprising a second H2O-rich stream (3), wherein the second solid oxide electrolysis (SOE) section is arranged to receive at least a portion of the second H2O-rich stream (3) and electrolyze it into the hydrogen-rich stream (21).

4. The methanol apparatus (100) according to any one of claims 2-3, wherein the heat exchanger section (50) is further arranged to transfer heat from the first oxygen-enriched stream (12) to the first H2O-enriched stream (2) and output a cooled first oxygen-enriched stream (12').

5. The methanol apparatus (100) according to any of the preceding claims, wherein the first H2O-rich stream (2) originates from outside the apparatus (i.e., the feed to the apparatus).

6. The methanol apparatus (100) according to any one of claims 1-4, wherein the first H2O-rich stream (2) is at least a portion of the tail gas stream from the methanol circuit (30) and / or the methanol distillation section (40).

7. The methanol apparatus (100) according to any one of claims 2-6, wherein the heat exchanger section (50) includes a steam drum arranged to vaporize liquid water into steam by means of heat from at least one of a carbon monoxide-rich stream (11) and a first oxygen-rich stream (12).

8. A method for producing methanol, the method comprising the following steps: - The carbon dioxide-rich feed (1) is supplied to the first SOE section (10) and electrolyzed into a carbon monoxide-rich stream (11) and an oxygen-rich stream (12) during the first electrolysis process; - Output hydrogen-rich stream (21) from the second electrolysis section (20); - At least a portion of the carbon monoxide-rich stream (11, 11') and at least a portion of the hydrogen-rich stream (21) are supplied to the methanol circuit (30) and converted into a crude methanol stream (31); - The crude methanol stream (31) from the methanol circuit (30) is supplied to the methanol distillation section (40) and distilled to output a purified methanol product stream (41). - By transferring the heat from the first electrolysis process in the first SOE section (10), the first H2O-rich stream (2) is converted into a first steam stream (13); - The first steam stream (13) is supplied to the methanol distillation section (40) and used as heat for the distillation of the crude methanol stream (31).

9. The method of claim 8, wherein heat transfer from the first electrolysis process is achieved by transferring heat from at least a portion of the carbon monoxide-rich stream (11) and / or at least a portion of the first oxygen-rich stream (12).

10. The method according to any one of claims 8-9, wherein i) at least a portion of the carbon monoxide-rich stream (11) and / or ii) at least a portion of the first oxygen-rich stream (12) is at a temperature of 200- Within the range of C, and i) at least a portion of the carbon monoxide-rich stream (11) and / or ii) at least a portion of the first oxygen-rich stream (12) have pressures in the range of 0-3 bar g.

11. The method according to any one of claims 8-10, wherein the first solid oxide electrolysis (SOE) stage (10) is carried out at 500- C, preferably 700- Operate within the temperature range of C.

12. The method according to any one of claims 8-11, wherein the second electrolysis stage is a solid oxide electrolysis (SOE) stage, which is carried out at 500- C, preferably 700- Operate within the temperature range of C.

13. The method according to any one of claims 8-12, wherein the temperature of the first steam stream (13) is 100– Between C, 150 is preferred – C, and among them. The pressure of the first steam stream (13) is between 3.5 and 9 bar g.

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