Closed loop hydrogen production and storage
A method includes extracting natural gas from a subsurface formation including a conventional gas reservoir via a first wellbore penetrating the subsurface formation, processing the natural gas in a surface processing facility and thereby generating hydrogen and a carbon dioxide (CO 2 ) brine, injecting at least a portion of the hydrogen into the subsurface formation via a second wellbore penetrating the subsurface formation for hydrogen storage, and injecting the CO 2 brine into a saline aquifer forming part of the subsurface formation via a third wellbore penetrating the subsurface formation.
1. A method, comprising:
extracting natural gas from a subsurface formation including a conventional gas reservoir via a first wellbore penetrating the subsurface formation;
processing the natural gas in a surface processing facility and thereby generating hydrogen and a carbon dioxide (CO 2 ) brine;
injecting at least a portion of the hydrogen into the subsurface formation via a second wellbore penetrating the subsurface formation for hydrogen storage;
maintaining reservoir pressure of the hydrogen injected into the subsurface formation via the natural gas operating as a cushion gas against the hydrogen; and
injecting the CO 2 brine into a saline aquifer forming part of the subsurface formation via a third wellbore penetrating the subsurface formation.
2. The method of claim 1 , wherein processing the natural gas comprises:
generating CO 2 from a methane reforming process; and
mixing the CO 2 with produced water to produce the CO 2 brine.
3. The method of claim 2 , wherein the methane reforming process is selected from the group consisting of steam methane reforming (SMR), autothermal reforming (ATR), dry reforming (DRM), partial oxidation (POX), pyrolysis, H 2 S Methane reforming, and any combination thereof.
4. The method of claim 2 , wherein generating the CO 2 from the methane reforming process is preceded by extracting hydrogen sulfide and carbon dioxide from the natural gas in a gas processing treatment.
5. The method of claim 4 , further comprising subjecting the natural gas to amine gas treating.
6. The method of claim 1 , wherein extracting the natural gas from the subsurface formation via the first wellbore is preceded by extracting natural gas from the subsurface formation via the second wellbore until a reservoir pressure at the second wellbore descends below a predetermined reservoir pressure.
7. The method of claim 1 , wherein extracting the natural gas from the subsurface formation via the first wellbore is preceded by:
extracting natural gas from the subsurface formation via the second wellbore; and
depleting a reservoir pressure of the subsurface formation via the second wellbore.
8. The method of claim 1 , further comprising enhancing reservoir pressure of the natural gas in the subsurface formation with the CO 2 brine.
9. The method of claim 8 , further comprising extracting the hydrogen from the subsurface formation using the reservoir pressure maintained by the cushion gas.
10. The method of claim 1 , wherein injecting the at least a portion of the hydrogen into the subsurface formation via the second wellbore further comprises:
conveying the hydrogen through a hydrogen separation membrane system arranged within the second wellbore; and
capturing and separating contaminants from the hydrogen with the hydrogen separation membrane system.
11. A closed-loop hydrogen production system, comprising:
a first wellbore penetrating a depleting subsurface formation for extracting natural gas from a conventional natural gas reservoir;
a surface processing facility in fluid communication with the first wellbore to receive and process the natural gas and thereby generate hydrogen (H 2 ) and a carbon dioxide (CO 2 ) brine;
a second wellbore penetrating the subsurface formation for injecting at least a portion of the hydrogen into the subsurface formation for storage, wherein reservoir pressure is maintained during injection of the hydrogen via the natural gas operating as a cushion gas against the hydrogen; and
a third wellbore penetrating the subsurface formation for injecting the CO 2 brine into a saline aquifer forming part of the subsurface formation.
12. The closed-loop hydrogen production system of claim 11 , further comprising a hydrogen separation membrane system arranged within the second wellbore and operable to separate contaminants from the hydrogen.
13. The closed-loop hydrogen production system of claim 11 , wherein the surface processing facility includes equipment designed to undertake a methane reformation process selected from the group consisting of steam methane reforming (SMR), autothermal reforming (ATR), dry reforming (DRM), partial oxidation (POX), pyrolysis, H 2 S Methane reforming, and any combination thereof.
14. A method, comprising:
extracting natural gas from a conventional subsurface formation including a gas reservoir via a first wellbore penetrating the subsurface formation;
processing the natural gas in a surface processing facility and thereby generating hydrogen and a carbon dioxide (CO 2 ) brine;
injecting the CO 2 brine into an aquifer forming part of the subsurface formation via a second wellbore penetrating the subsurface formation;
injecting at least a portion of the hydrogen into the subsurface formation for storage via a third wellbore penetrating the subsurface formation;
maintaining reservoir pressure of the hydrogen injected into the subsurface formation via the natural gas operating as a cushion gas against the hydrogen; and
supporting reservoir pressure of the conventional subsurface formation with the CO 2 brine.
15. The method of claim 14 , wherein processing the natural gas comprises:
generating CO 2 from a methane reforming process; and
mixing the CO 2 with produced water to produce the CO 2 brine.
16. The method of claim 14 , further comprising
extracting the hydrogen from the subsurface formation via the third wellbore using the reservoir pressure maintained by the cushion gas.
17. The method of claim 16 , wherein the cushion gas comprises natural gas remaining in the gas reservoir after the natural gas is extracted from the first wellbore.