Cement compositions with improved fluid loss characteristics and methods of cementing in surface and subterranean applications

Abstract

An improved fluid loss control additive and methods of using such compositions in surface and subterranean applications are provided. A method of cementing in a subterranean formation, that comprises providing a cement composition that comprises a cement, water, and a fluid loss control additive, the fluid loss control additive comprising an acrylic acid copolymer derivative, an iron compound, and at least one of a hydratable polymer or a dispersant, placing the cement composition into the subterranean formation, and permitting the cement composition to set therein, is provided. Also provided are methods of reducing the fluid loss from a cement composition, cement compositions, and fluid loss control additives.

Description

BACKGROUND The present invention relates to cementing operations, and more particularly, to cement compositions comprising an improved fluid loss control additive, and methods of using such compositions in surface and subterranean applications. Hydraulic cement compositions are commonly utilized in subterranean operations, particularly subterranean well completion and remedial operations. For example, hydraulic cement compositions are used in primary cementing operations whereby pipe strings such as casings and liners are cemented in well bores. In performing primary cementing, hydraulic cement compositions are pumped into the annular space between the walls of a well bore and the exterior surface of the pipe string disposed therein. The cement composition is permitted to set in the annular space, thereby forming an annular sheath of hardened substantially impermeable cement therein that substantially supports and positions the pipe string in the well bore and bonds the exterior s...

AI Technical Summary

Benefits of technology

In yet another embodiment, the present invention provides a method of reducing the fluid loss from a cement composition that comprises adding to the cement composition a fluid loss control additive comprising an acrylic acid copolymer derivative, an iron compound, and at least one of a dispersant or a hydratable polymer.

Problems solved by technology

Excessive fluid loss, inter alia, causes a cement composition to be prematurely dehydrated, which limits the amount of cement composition that can be pumped, decreases the compressive strength of the set cement composition, and prevents or reduces bond strength between the set cement composition and the subterranean zone, the walls of pipe, and / or the walls of the well bore.

The temperature limitations of certain of the AA / AMPS copolymers, e.g., ineffectiveness at temperatures above about 125° F. BHCT, are believed to be the result of hydrolysis of the amide groups.

The carboxylate groups formed by such hydrolysis convert the copolymers to materials, which lead to retarding of the setting of the cement and losses in the compressive strength of the set cement.

, certain of the AA / AMPS copolymers are less effective as a fluid loss control additive, requiring inclusion of larger amounts of the AA / AMPS copolymers than at higher temperatures. T

he inclusion of a sufficiently large amount of a fluid loss control additive to create a cement composition with acceptable fluid loss often creates viscosity and pumpability problems, since the addition of such copolymer directly affects the resultant slurry rheology. C

ertain AA / AMPS copolymers exhibit high viscosity and poor mixability, resulting in cement slurries having poor pumpability characteristics during cementing operations. M

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