CEMENT COMPOSITIONS COMPRISING HUMIC ACID GRAFTED FLUID LOSSCONTROL ADDITIVES AND METHODS OF USING THEM

摘要

A cement composition comprising water, a cement, and a fluid loss control additive, the fluid loss control additive comprising a graft copolymer. The graft copolymer comprises a backbone and at least four grafted monomers sel ected from the group consisting of 2-acrylamido-2-methylpropanesulfonic acid , acrylamide, acrylic acid, vinylphosphonic acid, diallyldimethylammonium ch loride, and salts thereof. The backbone of the graft copolymer comprises a h umic acid salt. The cement compositions may be used in cementing operations.