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CN-122029310-A - By means from CO2Waste heat of electrolysis to generate steam for steam electrolysis

CN122029310ACN 122029310 ACN122029310 ACN 122029310ACN-122029310-A

Abstract

The present invention relates to a system and a method for producing synthesis gas from a carbon dioxide rich feed stream and a water feedstock via electrolysis, wherein waste heat from the electrolysis of CO 2 is arranged to produce steam for steam electrolysis. More specifically, a system and method for producing a syngas stream is provided that includes a carbon dioxide rich feed stream, a first H 2 O rich feed stream, a first Solid Oxide Electrolysis (SOEC) section, a second Solid Oxide Electrolysis (SOEC) section, and a conversion section. Optimal utilization of thermal energy is achieved by heat transfer from the output of the first SOEC segment to the input of the second SOEC segment.

Inventors

  • S. H. Bartholdi

Assignees

  • 托普索公司

Dates

Publication Date
20260512
Application Date
20241115
Priority Date
20231115

Claims (20)

  1. 1. A system (100) for producing a syngas stream (101), the system (100) comprising: -a carbon dioxide rich feed stream (1); -a first H 2 O-rich feed stream (2); -a first Solid Oxide Electrolysis (SOEC) section (10); -a second Solid Oxide Electrolysis (SOEC) section (20); -a conversion section (30); -wherein the first SOEC section (10) is arranged to receive the carbon dioxide rich feed stream (1) and to electrolyze it into a carbon monoxide rich stream (11) and a first oxygen rich stream (12); -wherein the conversion section (30) is arranged to receive the first H 2 O-rich feed stream (2) and at least one of: i) At least a portion of the carbon monoxide rich stream (11), and Ii) at least a portion of the first oxygen-enriched stream (12), And outputting a SOEC vapor feed stream (52) at least one of: iii) A cooled carbon monoxide rich stream (31), and Iv) a cooled first oxygen-enriched stream (32); -wherein the second SOEC stage (20) is arranged to receive at least a portion of the SOEC steam feed stream (52) from the conversion stage (30) and electrolyze it into a hydrogen rich stream (21) and a second oxygen rich stream (22), and -Wherein at least a portion of the hydrogen rich stream (21) is arranged to be mixed with at least a portion of the cooled carbon monoxide rich stream (31) and/or at least a portion of the carbon monoxide rich stream (11 a) to provide a synthesis gas stream (101).
  2. 2. The system according to any one of the preceding claims, wherein the conversion section (30) comprises: -a first heat exchanger (40) arranged to transfer heat from at least a portion of the carbon monoxide rich stream (11) to at least a portion of the first H 2 O-rich feed stream (2) so as to output a first vapor stream (40A) and a cooled carbon monoxide rich stream (31), and/or A second heat exchanger (45) arranged to transfer heat from at least a portion of the first oxygen-enriched stream (12) to at least a portion of the first H 2 O-rich feed stream (2) so as to output a second vapor stream (45A) and a cooled first oxygen-enriched stream (32), Preferably, wherein at least a portion of the first vapor stream (40A) and/or at least a portion of the second vapor stream (45A) is arranged to be output from the reforming section (30) as the SOEC vapor feed stream (52).
  3. 3. The system according to any one of the preceding claims, wherein the conversion section (30) comprises a first heat exchanger (40) and/or a second heat exchanger (45), and further comprises a steam drum (50), wherein: -the steam drum (50) is arranged to receive at least a portion of the first H 2 O-rich feed stream (2) and to provide a second H 2 O-rich stream (51) and a SOEC steam feed stream (52); Wherein the first heat exchanger (40) is arranged to transfer heat from at least a portion of the carbon monoxide rich stream (11) to at least a portion of the second H 2 O rich stream (51) so as to output a first vapor stream (40A) and a cooled carbon monoxide rich stream (31), and/or wherein the second heat exchanger (45) is arranged to transfer heat from at least a portion of the first oxygen-enriched stream (12) to at least a portion of the second H 2 O rich stream (51) so as to output a second vapor stream (45A) and a cooled first oxygen-enriched stream (32), Wherein at least a portion of the first steam flow (40A) and/or at least a portion of the second steam flow (45A) is arranged to be fed to the steam drum (50).
  4. 4. The system of any of claims 1-2, wherein the conversion section (30) comprises a first heat exchanger (40) and/or a second heat exchanger (45), and further comprising a steam drum (50), the first heat exchanger (40) and/or the second heat exchanger (45) being arranged within the steam drum (50), and wherein: -the steam drum (50) is arranged to receive at least a portion of the first H 2 O-rich feed stream (2) and to provide a SOEC steam feed stream (52); -wherein the first heat exchanger (40) and/or the second heat exchanger (45) are arranged to gasify liquid water in the steam drum (50) into steam by means of heat from at least one of the carbon monoxide rich stream (11) and the first oxygen rich stream (12).
  5. 5. A system according to any one of claims 1-3, wherein the conversion section (30) comprises a first heat exchanger (40) and/or a second heat exchanger (45), and further comprising a steam drum (50), wherein the steam drum (50) comprises a third heat exchanger (55), and wherein: -the steam drum (50) is arranged to receive at least a portion of the first H 2 O-rich feed stream (2) and to provide a SOEC steam feed stream (52); -the first heat exchanger (40) is arranged to receive heat from the carbon monoxide rich stream (11) and to provide heat to the third heat exchanger (55); -the second heat exchanger (45) is arranged to receive heat from the first oxygen-enriched stream (12) and to provide heat to the third heat exchanger (55); -wherein the third heat exchanger (55) is arranged to gasify liquid water in the steam drum into steam by means of heat provided by the first heat exchanger (40) and/or the second heat exchanger (45).
  6. 6. The system according to any one of claims 3-5, wherein the reforming section (30) comprises a fourth heat exchanger (56) located within the steam drum (50), the fourth heat exchanger (56) being arranged to gasify liquid water in the steam drum (50) into steam by means of heat from at least one of the hydrogen rich stream (21) and the second oxygen rich stream (22).
  7. 7. The system according to any of the preceding claims, wherein the system further comprises an external steam feed (3), the external steam feed (3) being arranged to be fed to the second Solid Oxide Electrolysis (SOEC) section (20).
  8. 8. A synthetic alcohol plant comprising the system according to any one of claims 1-7, further comprising an alcohol synthesis section arranged to receive the synthesis gas stream (101) and output an alcohol rich stream.
  9. 9. A synthetic hydrocarbon plant comprising the system according to any of claims 1-7, the hydrocarbon plant further comprising a hydrocarbon synthesis section arranged to receive the synthesis gas stream (101) and output a hydrocarbon rich stream.
  10. 10. A method of producing a synthesis gas stream (101) in a system (100) according to any of claims 1-7, the method comprising the steps of: -providing a carbon dioxide rich feed stream (1) and a first H 2 O rich feed stream (2); -feeding said carbon dioxide rich feed stream (1) to a first Solid Oxide Electrolysis (SOEC) stage (10) and subjecting it to electrolysis to provide a carbon monoxide rich stream (11) and a first oxygen rich stream (12); -providing the first H 2 O-rich feed stream (2) to the conversion section (30) and at least one of: i) At least a portion of the carbon monoxide rich stream (11), and Ii) at least a portion of the first oxygen-enriched stream (12), And outputting from the reforming section (30) a SOEC vapor feed stream (52) at least one of: iii) A cooled carbon monoxide rich stream (31), and Iv) a cooled first oxygen-enriched stream (32); -feeding at least a portion of the SOEC vapor feed stream (52) to a second Solid Oxide Electrolysis (SOEC) section (20) and electrolyzing it to provide a hydrogen rich stream (21) and a second oxygen rich stream (22); -mixing at least a portion of the hydrogen rich stream (21) with at least a portion of the cooled carbon monoxide rich stream (31) and/or at least a portion of the carbon monoxide rich stream (11) to provide a synthesis gas stream (101).
  11. 11. The method according to claim 10, wherein the conversion section (30) comprises a first heat exchanger (40) and/or a second heat exchanger (45), wherein the method further comprises: -transferring heat from at least a portion of the carbon monoxide rich stream (11) to at least a portion of the first H 2 O-rich feed stream (2) in the first heat exchanger (40) so as to output a first vapor stream (40A) and a cooled carbon monoxide rich stream (31), and/or -Transferring heat from at least a portion of the first oxygen-enriched stream (12) to at least a portion of the first H 2 O-rich feed stream (2) in the second heat exchanger (40) so as to output a second vapor stream (45A) and a cooled first oxygen-enriched stream (32).
  12. 12. The method according to any one of claims 10-11, wherein the conversion section (30) further comprises a first heat exchanger (40) and/or a second heat exchanger (45), and further comprises a steam drum (50), wherein the method further comprises: -feeding at least a portion of the first H 2 O-rich feed stream (2) to the steam drum (50) so as to provide a second H 2 O-rich stream (51) and a SOEC steam feed stream (52) from the steam drum (50); -feeding at least a portion of the second H 2 O-rich stream (51) to the first heat exchanger (40) and transferring heat from at least a portion of the carbon monoxide rich stream (11) to at least a portion of the first H 2 O-rich stream (51) in the first heat exchanger (40) so as to output a first vapor stream (40A) and a cooled carbon monoxide rich stream (31), and/or Feeding at least another portion of the second H 2 O-rich stream (51) to the second heat exchanger (45) and transferring heat from at least a portion of the first oxygen-rich stream (12) to at least a portion of the first H 2 O-rich stream (51) in the second heat exchanger (45) to output a second vapor stream (45A) and a cooled first oxygen-rich stream (32), The following steps are: -feeding at least a portion of the first steam flow (40A) and/or at least a portion of the second steam flow (45A) to the steam drum (50).
  13. 13. The method according to any one of claims 10-12, wherein the conversion section (30) further comprises a first heat exchanger (40) and/or a second heat exchanger (45), and further comprises a steam drum (50), wherein the first heat exchanger (40) and/or the second heat exchanger (45) are arranged within the steam drum (50), and wherein the method further comprises: -feeding at least a portion of the first H 2 O-rich feed stream (2) to the steam drum (50) and providing a SOEC steam feed stream (52) from the steam drum (50); -vaporizing liquid water into steam in the first heat exchanger (40) and/or the second heat exchanger (45) within the steam drum (50) by means of heat from at least one of the carbon monoxide rich stream (11) and the first oxygen rich stream (12).
  14. 14. The method according to any one of claims 10-12, wherein the conversion section (30) further comprises a first heat exchanger (40) and/or a second heat exchanger (45), and further comprises a steam drum (50), wherein the steam drum (50) comprises a third heat exchanger (55), wherein the method further comprises: -feeding at least a portion of the first H 2 O-rich feed stream (2) to the steam drum (50) and providing a SOEC steam feed stream (52) from the steam drum (50); -transferring heat from the carbon monoxide rich stream (11) in the first heat exchanger (40) and providing the heat to the third heat exchanger (55) and/or transferring heat from the first oxygen rich stream (12) to the second heat exchanger (45) and providing the heat to the third heat exchanger (55); -vaporizing liquid water in the steam drum (50) into steam in the third heat exchanger (55) by means of heat provided by the first heat exchanger (40) and/or the second heat exchanger (45).
  15. 15. The method of any of claims 13-14, wherein the system further comprises a fourth heat exchanger (56) located within the steam drum (50), wherein the method further comprises vaporizing liquid water in the steam drum (50) into steam by means of heat supplied to the fourth heat exchanger (56) from at least one of the hydrogen rich stream (21) and the second oxygen rich stream (22).
  16. 16. The method according to any one of claims 10-15, wherein the system further comprises an external steam feed (3), and wherein the method further comprises feeding the external steam feed (3) to the second Solid Oxide Electrolysis (SOEC) section (20).
  17. 17. The method according to any one of claims 10-16, wherein i) at least a portion of the carbon monoxide rich stream (11) and/or ii) at least one of the at least a portion of the first oxygen rich stream (12) has a temperature in the range of 500-200 ℃, and i) at least a portion of the carbon monoxide rich stream (11) and/or ii) at least one of the at least a portion of the first oxygen rich stream (12) has a pressure in the range of 0-3 bar g.
  18. 18. The method according to any one of claims 10-17, wherein the first Solid Oxide Electrolysis (SOEC) stage is operated at a temperature in the range of 500-900 ℃, preferably 700-800 ℃.
  19. 19. The method according to any one of claims 10-18, wherein the second Solid Oxide Electrolysis (SOEC) stage is operated at a temperature in the range of 500-900 ℃, preferably 700-800 ℃.
  20. 20. The method according to any one of claims 10-19, wherein the SOEC vapor feed stream (52) has a temperature between 100-210 ℃, preferably 130-160 ℃, and wherein the SOEC vapor feed stream (52) has a pressure between 1-4 bar g.

Description

Generating steam for steam electrolysis using waste heat from CO 2 electrolysis Technical Field The present invention relates to a system and a method for producing synthesis gas from a carbon dioxide rich stream and a water feedstock via electrolysis, wherein waste heat from the electrolysis of CO 2 is arranged to produce steam for steam electrolysis. The invention also relates to a device comprising the system. In this way, the synthesis gas may be used to produce synthetic alcohols (e.g. methanol) or to produce synthetic hydrocarbons (e.g. synthetic fuels (e.g. jet fuel and/or kerosene)) by fischer-tropsch synthesis (FT) or to produce e.g. Substitute Natural Gas (SNG) (e.g. methane). Background Continuous efforts are being made to replace fossil fuels and to shift toward sustainable production and storage of energy and chemicals. An important contribution to pushing such efforts is "power transfer X" (PtX), which relates to systems and methods that enable power conversion, energy storage, and re-conversion pathways to use electrical energy from wind and solar power generation to store energy in the form of chemicals (e.g., synthetic alcohol, synthetic fuel, or substitute natural gas). One way to use electrical energy is to electrolyze water to produce H 2. It is known to subsequently combine H 2 and CO 2 into a mixed stream and convert the mixed stream into a CO and H 2 rich synthesis gas which can be further converted into valuable products such as alcohols (including methanol), synthetic fuels (e.g. jet kerosene and/or diesel) or substitute natural gas. However, currently, the production of synthesis gas from H 2 and CO 2 for the synthesis of alcohols and synthetic hydrocarbons is generally inefficient and energy consuming. Recent developments have disclosed the possibility of providing synthesis gas by combining a H 2 rich stream from H 2 O electrolysis with a CO rich stream from CO 2 electrolysis, optionally wherein the electrolysis is performed separately. Within such systems, an external heater unit may be arranged or alternatively a downstream process may be arranged to provide heat to drive the H 2 O electrolysis. See, for example, WO 2022/136374, wherein two separate SOEC cells are used to produce H 2 and CO, respectively, and to combine them into synthesis gas, wherein the ratio of H 2 to CO can be easily controlled. However, there is a general need to further develop such systems to make these systems viable for sustainable production and to reduce energy consumption, thereby reducing the CO 2 footprint of such systems and methods. Disclosure of Invention The present inventors have discovered that in a system and method for electrolyzing a carbon dioxide rich feed stream to a carbon monoxide rich stream using a first solid oxide electrolysis stage and a SOEC vapor feed stream to a hydrogen rich stream using a second Solid Oxide Electrolysis (SOEC) stage, the energy required to produce a synthesis gas stream can be reduced if the first H 2 O rich feed stream is allowed to be in thermal communication with at least one product stream provided by the first solid oxide electrolysis stage. More specifically, in a first aspect, the present invention relates to a system for producing a syngas stream, the system comprising: -a carbon dioxide rich feed stream; -a first H 2 O-rich feed stream; -a first Solid Oxide Electrolysis (SOEC) section; -a second Solid Oxide Electrolysis (SOEC) section; -a conversion section; -wherein the first SOEC section is arranged to receive and electrolyze the carbon dioxide rich feed stream into a carbon monoxide rich stream and a first oxygen rich stream; -wherein the conversion section is arranged to receive the first H 2 O-rich feed stream and at least one of: i) At least a portion of the carbon monoxide rich stream, and Ii) at least a portion of the first oxygen-enriched stream, And outputting a SOEC vapor feed stream, at least one of: iii) A cooled carbon monoxide rich stream, and Iv) a cooled first oxygen-enriched stream; -wherein the second SOEC section is arranged to receive at least a portion of the SOEC vapor feed stream and electrolyze it into a hydrogen-rich stream and a second oxygen-rich stream; -wherein at least a portion of the hydrogen-rich stream is arranged to be mixed with at least a portion of the cooled carbon monoxide-rich stream and/or at least a portion of the carbon monoxide-rich stream to provide a synthesis gas stream. In a second aspect, the invention relates to a synthetic alcohol plant comprising a system as disclosed herein, the synthetic alcohol plant further comprising an alcohol synthesis section arranged to receive the synthesis gas stream and output an alcohol rich stream. In a third aspect, the invention relates to a hydrocarbon synthesis plant comprising a system as disclosed herein, the hydrocarbon plant further comprising a hydrocarbon synthesis section arranged to receive the synthesis gas stream and to output a hydrocarbon rich stre