SYSTEM AND METHOD FOR FACILITATING SUBTERRANEAN HYDROCARBON EXTRACTION UTILIZING ELECTROCHEMICAL REACTIONS WITH METALS

• US 20170284180A1
• Filed: 09/04/2015
• Published: 10/05/2017
• Est. Priority Date: 09/05/2014
• Status: Active Grant

• Current Assignee: Arizona Board of Regents (University of Arizona)
• Original Assignee: Arizona Board of Regents (University of Arizona)
• Inventors: SWITZER, Elise, FRIESEN, Cody, LORZEL, Heath
• Granted Patent: US 10,458,220 B2
• Time in Patent Office: Days
• CPC Class Codes: C09K 8/70 characterised by their form or by the form of their components, e.g. foams
• CPC Class Codes: C09K 8/80 Compositions for reinforcing fractures, e.g. compositions of proppants used to keep the fractures open
• CPC Class Codes: C09K 8/92 characterised by their form or by the form of their components, e.g. encapsulated material C09K8/70 takes precedence
• CPC Class Codes: E21B 43/2605 using gas or liquefied gas
• CPC Class Codes: E21B 43/267 reinforcing fractures by propping

Abstract

Methods and systems for facilitating extraction of subterranean hydrocarbons from a geologic structure. The present methods include causing corrosion of a base metal within a geologic structure to produce a gaseous product to increase pressure and form fractures in the geologic structure. Some embodiments of the present methods include injecting a fluid composition comprising the base metal into a wellbore (e.g., into a geologic structure via the wellbore).

Claims

1. A method to facilitate extraction of subterranean hydrocarbons from a geologic structure, the method comprising:

injecting a first fluid composition comprising a base metal and proppant particles into a first wellbore that extends into the geologic structure, the base metal particles having a first density and the proppant particles having a second density, wherein a ratio of the second density to the first density is equal to or less than 5;

wherein corrosion of the base metal in the wellbore results in electrochemical oxidation of the base metal and electrochemical reduction of a reducible species that generates a gaseous product, thereby increasing the subterranean pressure in at least a portion of the wellbore; and

wherein the base metal corrodes in the wellbore at a rate sufficient to produce a gaseous product that induces fractures within the geologic structure, and at least some of the induced fractures are kept open by the proppant particles thereby facilitating egress of hydrocarbons from the geologic structure.

2. The method of claim 1, wherein a ratio of the second density to the first density is equal to or less than 2.

3. The method of claim 1, wherein a ratio of the second density to the first density is equal to or less than 1.2.

4. The method of claim 1, wherein a ratio of the second density to the first density is equal to or less than 1.1.

5. The method of claim 1, wherein a ratio of the second density to the first density is equal to or less than 1.02.

23. The method of any of claims 1-21, wherein the base metal comprises one or more of:

alkaline metals, alkaline earth metals, transition metals and metalloids.

24. The method of any of claims 1-21, wherein the base metal comprises one or more of:

aluminum, magnesium, sodium, calcium, zinc, indium, lead, manganese, chromium, iron, cadmium, cobalt, nickel, tin, lead, boron, silicon, and combinations thereof.

25. The method of any of claims 1-21, wherein the base metal comprises one or more of:

aluminum, magnesium, or a combination thereof.

26. The method of any of claim 1-21, wherein the base metal is configured in a physical form having a particles with an aggregate transverse dimension of between 1 and 100 microns.

27. The method of any of claims 1-21, wherein at least a portion of the base metal comprises a physical form of one or more of:

a powder, particles, and flakes.

28. The method of any of claims 1-21, wherein the first fluid composition further comprises a surface passivating additive.

29. The method of claim 28, wherein the surface passivating additive is configured to degrade over time.

30. The method of claim 29, wherein the surface passivating additive comprises an anion.

31. The method of claim 29, wherein the surface passivating additive includes one or more of:

a sulfate, a phosphate, a nitrite, a chromate, a phosphonate, and a molybdate.

36. The method of any of claims 1-21, wherein the reducible species comprises water and the gaseous product comprises hydrogen gas.

37. The method of any of any of claims 1-10, further comprising:

injecting a third fluid composition comprising a deactivating additive into a wellbore;

wherein the deactivating additive deactivates the corrosion process such that the rate of electrochemical oxidation of the base metal and electrochemical reduction of a reducible species is decreased.

38. The method of claim 37, wherein the deactivating additive comprises one or more of:

a water, an acid, an acid precursor, a base, a base precursor, an anion, an amine, an amine ester, an organoamine, a nitrite, a borate, a phosphate, a phosphate ester, a dispersant, and any combination thereof.

39. The method of claim 37, wherein the deactivating additive increases the pH proximal to the base metal.

40. The method of claim 37, wherein the deactivating additive increases a hydrogen overvoltage of the base metal.

41. The method of claim 37, wherein the deactivating additive increases the pH in proximity to the base metal.

42. The method of any of claims 1-5 and 11-21, further comprising:

substantially sealing a portion of the wellbore after injection of the second fluid composition to restrict the sealed portion of the subterranean volume and thereby maximize a pressure gradient resulting from generation of the gaseous product.

43. The method of claim 42, wherein a branching bore extends from the first wellbore into the geologic structure.

44. The method of claim 43, further comprising:

selectively providing the first fluid composition comprising a base metal into the branching bore; and

injecting the second fluid composition comprising an activating additive into the branching bore.

45. The method of any of claims 1-5 and 11-21, further comprising:

maximizing local pressure gradients within the geologic structure by selectively positioning the first fluid composition in a localized manner within the wellbore, within a branching bore, within a natural subterranean discontinuity (fissures, pores, fractures, joint, faults), proximal to natural deposits of ore (vein, seam pockets), proximal to natural deposits of minerals, or combinations thereof.

46. The method of claim 45, further comprising:

maximizing local pressure gradients within the geologic structure by selectively positioning the second fluid composition in a localized manner within the wellbore, within a branching bore, within a natural subterranean discontinuity (fissures, pores, fractures, joint, faults), proximal to natural deposits of ore (vein, seam pockets), proximal to natural deposits of minerals, or combinations thereof.

47. The method of any of claims 1-5 and 11-21, wherein the geologic structure comprises one or more of:

a shale formation, a siltstone formation, a sandstone formation, and a conglomerate formation.

48. The method of any of claims 1-5 and 11-21, wherein the subterranean hydrocarbons comprise one or more of:

natural gas, natural gas liquids, kerogen, coal seam gas, tight gas, shale gas, tight oil, shale oil, coal bed methane, gas hydrates.

49. The method of any of claims 1-5 and 11-21, further comprising:

extracting the first fluid composition from the wellbore.

50. A method comprising:

extracting a hydrocarbon from a wellbore in fluid communication with a plurality of fractures formed by the method of any of claims 1-49.

6. A method to facilitate extraction of subterranean hydrocarbons from a geologic structure, the method comprising:

injecting a first fluid composition comprising a base metal into a first wellbore that extends into the geologic structure;

wherein corrosion of the base metal in the wellbore results in electrochemical oxidation of the base metal and electrochemical reduction of a reducible species that generates a gaseous product and a metal oxide product;

wherein the gaseous product increases the subterranean pressure, thereby inducing fractures within the geologic structure; and

,

wherein induced fractures are kept open by the metal oxide product, thereby facilitating hydrocarbon egress from the geologic structure.

7. The method of claim 6, wherein the metal oxide product comprises less than 40% fines under 2,000 to 14,000 psi closure pressure, and acts as a fracture proppant after it is formed within the wellbore.

8. The method of claim 6, wherein the metal oxide product comprises less than 30% fines under 2,000 to 14,000 psi closure pressure, and acts as a fracture proppant after it is formed within the wellbore.

9. The method of claim 6, wherein the metal oxide product comprises less than 10% fines under 2,000 to 14,000 psi closure pressure, and acts as a fracture proppant after it is formed within the wellbore.

10. The method of claim 6, wherein the metal oxide product has a conductivity range from 100 millidarcies per foot for a 14,000 psi closure stress to 40,000 millidarcies per foot for 2,000 psi closure stress.

11. A method to facilitate extraction of subterranean hydrocarbons from a geologic structure by sequentially injecting alternate stages of fracturing fluid compositions from a wellhead into a wellbore, the method comprising:

injecting a first fluid composition comprising base metal particles into the wellbore for a first predetermined time period;

injecting a second fluid composition comprising an activating additive into the wellbore for a second predetermined time period;

wherein the first fluid and second fluid are injected in sequence to produce an electrochemical reaction at a distance from the wellhead;

wherein the activating additive activates a corrosion process resulting in electrochemical oxidation of the base metal and electrochemical reduction of a reducible species; and

,

wherein the electrochemical reaction between the base metal and a reducible species that generates a gaseous product and a metal oxide product.

12. The method of claim 11, further comprising:

injecting a third fluid composition comprising a deactivating additive for a third predetermined time period, wherein the deactivating additive deactivates the corrosion process.

13. The method of claim 11, where the distance from the wellhead is within a predetermined range.

14. The method of claim 13, wherein the predetermined distance range from the wellhead is determined by the first predetermined time period, the second predetermined time period, or both.

15. The method of claim 11, wherein the first predetermined time period and the second predetermined time period are each between 10 seconds and thirty minutes.

16. The method of claim 11, wherein the first predetermined time period and the second predetermined time period are each between 50 seconds and 500 seconds.

17. The method of claim 11, wherein the electrochemical reaction rate is adjusted by altering the injection rate of the first fluid composition, the second fluid composition, or both.

18. The method of claim 11, further comprising injecting fluids comprising proppants that differ in at least one of:

density, size, concentration, and a combination thereof.

19. The method of claim 11, further comprising alternating injection of fluids with proppant and fluids without proppant.

20. The method of claim 11, wherein the base metal particles are encapsulated by an encapsulating material, and the second fluid composition comprises an activating additive that dissolves the encapsulating material.

21. The method of claim 20, wherein the base metal particles are encapsulated by a surfactant, polymer, sulfate, carboxylate, ester, other less reactive metals, other metals that react at a different pH or in response to other stimuli, or a combinations thereof.

22. The method of any of claims 11-21, wherein the base metal corrodes in the wellbore at a rate that is low enough to produce a gaseous product that provides local sustained pressure substantially without inducing fractures in the geologic structures.

32. The method of any of claims 11-21, wherein the activating additive comprises one or more of:

an acid, an acid precursor, a halide ion, and a combination thereof.

33. The method of claim 32, wherein the activating additive decreases the pH proximal to the base metal.

34. The method of claim 32, wherein the activating additive decreases a hydrogen overvoltage of the base metal.

35. The method of claim 32, wherein the activating additive disrupts a passive oxide film of the base metal.