Settable, form-filling loss circulation control compositions comprising in situ foamed calcium aluminate cement systems and methods of using them

• US 10,259,985 B1
• Filed: 01/24/2018
• Issued: 04/16/2019
• Est. Priority Date: 01/24/2018
• Status: Active Grant

• Current Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Original Assignee: Saudi Arabian Oil Company (Government of Saudi Arabia)
• Inventors: Reddy, B. Raghava
• Primary Examiner(s): Green, Anthony J
• Application Number:
  US15/879,179
• Time in Patent Office: 447 Days
• CPC Class Codes: C04B 2103/40 Surface-active agents, dispersants
• CPC Class Codes: C04B 2103/46 Water-loss or fluid-loss reducers, hygroscopic or hydrophilic agents, water retention agents
• CPC Class Codes: C04B 24/12 Nitrogen containing compounds organic derivatives of hydrazine hydrazine C04B22/00
• CPC Class Codes: C04B 24/129 Compounds containing one or more nitrogen-to-nitrogen double bonds, e.g. azo-compounds
• CPC Class Codes: C04B 28/06 Aluminous cements monolithic refractories or refractory mortars C04B35/66
• CPC Class Codes: C04B 38/02 by adding chemical blowing agents
• CPC Class Codes: C04B 7/32 Aluminous cements
• CPC Class Codes: C09K 8/473 Density reducing additives, e.g. for obtaining foamed cement compositions
• CPC Class Codes: C09K 8/487 Fluid loss control additives; Additives for reducing or preventing circulation loss
• CPC Class Codes: E21B 33/13 Methods or devices for cementing, for plugging holes, crevices or the like

Abstract

This document relates to settable, hydraulic, non-Portland foamed cement compositions comprising nitrogen gas-generating compositions used for loss circulation control.

Claims

1. A foamed cementitious composition, comprising:

calcium aluminate;

a nitrogen gas-generating compound;

an amine activator to accelerate generation of gas from the nitrogen gas-generating compound, the amine activator comprising an ethyleneamine; and

a foam surfactant.

2. The composition of claim 1, comprising a viscosifier comprising xanthan or diutan, or both, and wherein the calcium aluminate comprises greater than or about 68.5% alumina and less than or about 31% calcium oxide.

3. The composition of claim 1, wherein the foam surfactant is selected from the group consisting of an alkyl sulfate salt with a C₁₂-C₁₄ carbon chain, a betaine, and combinations thereof.

4. The composition of claim 1, wherein the foam surfactant comprises cocoamidopropyl hydroxysultaine.

5. The composition of claim 1, wherein the nitrogen gas-generating compound is an azo compound.

6. The composition of claim 5, wherein the azo compound is azodicarbonamide.

7. The composition of claim 5, comprising a polymeric viscosifier, wherein the azo compound is about 1% to about 10% by weight of the calcium aluminate, and wherein the amine activator further comprises hydrazine sulfate.

8. The composition of claim 5, wherein the ethyleneamine comprises ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetetramine (TETA), or tetraethylenepentamine (TEPA), or any combinations thereof.

9. The composition of claim 8, wherein the weight ratio of the azo compound to the amine activator is about 5:

1 to about 1;

5.

10. The composition of claim 8, wherein the ethyleneamine comprises TEPA.

11. The composition of claim 5, further comprising a set retarder selected from the group consisting of hexametaphosphate, sodium borate, sodium citrate, citric acid, and an aminophosphonate, wherein the azo compound comprises a derivative of azodicarboxylic acid.

12. The composition of claim 11, further comprising a viscosifier, wherein the derivative comprises ester comprising at least one of diisopropyl azodicarboxylate (DIAD) or diethyl azodicarboxylate (DEAD).

13. The composition of claim 1, further comprising a filler comprising at least one of fly ash, sand, clay, or vitrified shale.

14. The composition of claim 13, wherein the composition does not contain an oxidizer, wherein the filler comprises fly ash, and wherein the foam surfactant comprises a surfactant solution in at least one of water or alcohol.

15. The composition of claim 1, wherein the composition does not contain calcium silicates, and wherein the foamed cementitious composition to generate an amount of gas of 65% to 90% by volume of the foamed cementitious composition.