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

Patent metadata

Field	Value
Publication number	US-10414968-B2
Application number	US-201916256466-A
Country	US
Kind code	B2
Filing date	Jan 24, 2019
Priority date	Jan 24, 2018
Publication date	Sep 17, 2019
Grant date	Sep 17, 2019

Abstract

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

First claim

What is claimed is:

1. A foamed cementitious composition, comprising:
calcium aluminate comprising greater than or about 68.5% alumina and less than or about 31% calcium oxide;
an azo compound in an amount of about 1% to about 10% by weight of the calcium aluminate;
an amine activator comprising an ethyleneamine, wherein the weight ratio of the azo compound to the amine activator is about 5:1 to about 1:5; and
a foam surfactant.

2. The composition of claim 1 , wherein the ethyleneamine comprises tetraethylenepentamine (TEPA).

3. The composition of claim 1 , further comprising a viscosifier, wherein the azo compound comprises azodicarbonamide, and wherein the foam surfactant comprises an alky sulfate salt or a betaine, or both.

Assignees

• Saudi Arabian Oil Co

Inventors

• Reddy B Raghava

Classifications

• C04B38/02

  by adding chemical blowing agents · CPC title

• C09K8/487 Primary

  Fluid loss control additives; Additives for reducing or preventing circulation loss · CPC title

• C04B28/06

  Aluminous cements (monolithic refractories or refractory mortars C04B35/66) · CPC title

• C09K8/473

  Density reducing additives, e.g. for obtaining foamed cement compositions · CPC title

• E21B33/13

  Methods or devices for cementing, for plugging holes, crevices or the like · CPC title