Removing scale from a wellbore

• US 10,677,020 B2
• Filed: 11/08/2019
• Issued: 06/09/2020
• Est. Priority Date: 03/07/2018
• Status: Active Grant

• Current Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Original Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Inventors: Bulekbay, Aslan, Attiah, Sultan, Al-Mutairi, Talal, Alsousy, Abdulrahman
• Primary Examiner(s): DiTrani Leff, Angela M
• Application Number:
  US16/678,839
• Publication Number:
  US 20200072023A1
• Time in Patent Office: 214 Days
• Field of Search: None
• CPC Class Codes: C09K 8/528 inorganic depositions, e.g. sulfates or carbonates
• CPC Class Codes: C09K 8/536 characterised by their form or by the form of their components, e.g. encapsulated material
• CPC Class Codes: E21B 33/068 having provision for introducing objects or fluids into, or removing objects from, wells cementing-heads E21B33/05
• CPC Class Codes: E21B 37/06 using chemical means for preventing or limiting , e.g. eliminating, the deposition of paraffins or like substances
• CPC Class Codes: E21B 41/0078 Nozzles used in boreholes drilling by liquid or gas jets E21B7/18; drill bits with nozzles E21B10/60; perforators using direct fluid action E21B43/114; obtaining a slurry of minerals using nozzles E21B43/29

Abstract

Supercritical carbon dioxide is directed into a wellbore to a specified depth. The supercritical carbon dioxide is directed at an inner surface of the wellbore at the specified depth. Scale is removed from the wall of the wellbore with the supercritical carbon dioxide.

Claims

1. A method performed by supercritical carbon dioxide in a wellbore, the method comprising:

the supercritical carbon dioxide traveling through a workstring positioned in a wellbore to a specified depth within the wellbore;

the supercritical carbon dioxide impacting a wall of the wellbore at the specified depth; and

reducing skin-effects on the wellbore in response to impacting the supercritical carbon dioxide, wherein the supercritical carbon dioxide changes phase to a solid phase, a liquid phase, and a gas phase of carbon dioxide.

2. The method of claim 1, wherein the skin-effects comprise scale, the method further comprising removing the scale.

3. The method of claim 2, wherein the scale is a non-soluble scale.

4. The method of claim 2, further comprising lifting the removed scale to a topside facility.

5. The method of claim 1, further comprising flowing reservoir fluid through the wellbore in an underbalanced condition.

6. The method of claim 1, wherein the solid phase and liquid phase of carbon dioxide change to a gaseous phase after impacting the wall of the wellbore.