A Method of Abandoning a Well

• US 20200131887A1
• Filed: 12/09/2016
• Published: 04/30/2020
• Est. Priority Date: 12/11/2015
• Status: Active Grant

• Current Assignee: Italmatch Chemicals GB Limited (Italmatch Chemicals S.p.A)
• Original Assignee: Aubin Limited (Italmatch Chemicals S.p.A)
• Inventors: Collins, Patrick Joseph
• Granted Patent: US 10,934,808 B2
• Time in Patent Office: Days
• CPC Class Codes: C09K 8/426 for plugging
• CPC Class Codes: C09K 8/5045 containing inorganic compounds
• CPC Class Codes: E21B 33/138 Plastering the borehole wall; Injecting into the formation
• CPC Class Codes: E21B 37/06 using chemical means for preventing or limiting , e.g. eliminating, the deposition of paraffins or like substances

Abstract

A method of a bandoning a well in a reservoir. The method including the step of forming a scale in the reservoir by introducing into the reservoir a first solution comprising a first scale precursor and a second solution comprising a second scale precursor and a scale inhibitor. The first solution and second solution are able to react together to form the scale. The method further includes the step of at least partially filling the well with cement.

Claims

1. A method of abandoning a well in a reservoir, the method comprising the step of forming a scale in the reservoir by introducing into the reservoir a first solution comprising a first scale precursor, a second solution comprising a second scale precursor and a scale inhibitor, wherein the first solution and second solution are able to react together to form the scale, the method further including the step of at least partially filling the well with cement.

2. A method as claimed in claim 1, wherein the cement comprises one or more of calcium oxide, silicon dioxide, aluminium oxide, a sulphate and ferric oxide.

3. A method as claimed in claim 1, wherein the cement is a component of concrete, the concrete comprises an aggregate, the cement and water.

4. A method as claimed in claim 1, wherein the well has perforations therein, the method further including the step of at least partially blocking the perforations with a third solution.

5. A method as claimed in claim 4, wherein the third solution comprises one or more of silicone, a vinyl silicone, a vinyl terminated silicone, polydimethylsiloxane, vinyl polydimethylsiloxane, a fumed silica, a silica flour and a siloxane.

6. A method as claimed in claim 1, wherein the first and second solutions are introduced separately into the reservoir via separate pathways.

7. A method as claimed in claim 1, wherein both the first and second solution each contain a scale inhibitor.

8. A method as claimed in claim 1, wherein the first scale precursor is a soluble inorganic salt of a Group 1 metal.

9. A method as claimed in claim 8, wherein the salt is selected from the group comprising:

a sodium or potassium salt of a sulphate, carbonate or bicarbonate.

10. A method as claimed in claim 9, wherein the salt is sodium sulphate.

11. A method as claimed in claim 8, wherein the second scale precursor is a soluble inorganic salt of a Group 2 metal.

12. A method as claimed in claim 11, wherein the salt is selected from the group comprising a calcium or barium salt of a halide or nitrate.

13. A method as claimed in claim 12, wherein the salt is calcium chloride.

14. A method as claimed in claim 1, wherein the scale inhibitor is one or more of a phosphonate polymer;

a polyacrylate polymer;

a polycarboxylic acid based polymer;

a polycarboxylic acid based polysulphonate;

a phosphinocarboylic acid salt; and

materials thereof.

15. A method as claimed in claim 1, wherein the scale inhibitor is a copolymer of acrylic acid and 2-acrylamido-2-methylpropane sulfonic acid, or a phosphonate.

16. A method as claimed claim 1, wherein the total amount of scale inhibitor provided in the second solution is reduced during the method of abandoning the well in the reservoir.

17. A method as claimed in claim 16, wherein over the duration of the method of abandoning the well in the reservoir, the concentration of scale inhibitor is reduced by at least 25% relative to its initial concentration.

18. A method as claimed in claim 11, wherein the scale inhibitor is one or more of a phosphonate polymer;

a polyacrylate polymer;

a polycarboxylic acid based polymer;

a polycarboxylic acid based polysulphonate;

a phosphinocarboylic acid salt; and

materials thereof.