Settable, form-filling loss circulation control compositions comprising in situ foamed non-hydraulic sorel cement systems and method of use

• US 10,287,480 B1
• Filed: 09/21/2018
• Issued: 05/14/2019
• 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:
  US16/137,911
• Time in Patent Office: 235 Days
• CPC Class Codes: C04B 12/025 Phosphates of ammonium or of the alkali or alkaline earth metals
• CPC Class Codes: C04B 2103/40 Surface-active agents, dispersants
• CPC Class Codes: C04B 2103/44 Thickening, gelling or viscosity increasing agents
• CPC Class Codes: C04B 2111/00689 of the setting type
• CPC Class Codes: C04B 22/064 of the alkaline-earth metals
• CPC Class Codes: C04B 24/12 Nitrogen containing compounds organic derivatives of hydrazine hydrazine C04B22/00
• CPC Class Codes: C04B 24/16 Sulfur-containing compounds
• CPC Class Codes: C04B 28/30 containing magnesium cements or similar cementsmagnesium oxide cements C04B28/10
• CPC Class Codes: C04B 28/32 Magnesium oxychloride cements, e.g. Sorel cement
• CPC Class Codes: C04B 28/34 containing cold phosphate binders
• CPC Class Codes: C04B 38/02 by adding chemical blowing agents
• CPC Class Codes: C04B 38/10 by using foaming agents C04B38/02 takes precedenceor by using mechanical means, e.g. adding preformed foam
• CPC Class Codes: C04B 9/00 Magnesium cements or similar cements
• CPC Class Codes: C04B 9/02 Magnesium cements containing chlorides, e.g. Sorel cement
• CPC Class Codes: C04B 9/04 Magnesium cements containing sulfates, nitrates, phosphates or fluorides
• 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
• CPC Class Codes: Y02W 30/91 Use of waste materials as fillers for mortars or concrete

Abstract

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

Claims

1. A foamed cementitious composition, comprising:

magnesium oxide (MgO);

magnesium chloride hexahydrate (MgCl₂.6H₂O);

a nitrogen gas-generating compound; and

a foam surfactant.

2. 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 a hydroxysultaine.

3. The composition of claim 2, wherein the foam surfactant is cocoamidopropyl hydroxysultaine.

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

5. The composition of claim 4, wherein the azo compound is azodicarbonamide.

6. The composition of claim 4, wherein the azo compound is about 1% to about 10% by weight of the MgO.

7. The composition of claim 4, further comprising an amine activator selected from the group consisting of carbohydrazide (CHZ), tetraethylenepentamine (TEPA), and hydrazine sulfate.

8. The composition of claim 7, wherein the weight ratio of the azo compound to the amine activator is about 5:

1 to about 1;

5.

9. The composition of claim 7, wherein the amine activator is CHZ.

10. The composition of claim 9, wherein the composition further comprises an oxidizer.

11. The composition of claim 1, further comprising a set retarder selected from the group consisting of hexametaphosphate, sodium borate, sodium citrate, citric acid, and an aminophosphonate.

12. The composition of claim 1, further comprising a viscosifier.

13. The composition of claim 1, wherein the pH of the foamed cementitious composition is greater than about 4.