Abstract: A cement includes a cement mixture and a permeable, micro-cluster silica material present in an amount from about 10 percent to about 30 percent by weight of the cement mixture. The cement blend may be used in casing a borehole when appropriate fluid loss agents are included in the cement blend. Additionally, a cement additive is added to a cement mixture to provide the cement blend. This cement additive can be formulated in a kit form.

Abstract: A cement blend includes a cement mixture and a permeable, micro-cluster silica material present in an amount from about 10 percent to about 30 percent by weight of the cement mixture. The cement blend may be used in casing a borehole when appropriate fluid loss agents are included in the cement blend. Additionally, a cement additive is added to a cement mixture to provide the cement blend. This cement additive can be formulated in a kit form.

Abstract: Powdered and liquid fluid loss additives are disclosed for use in cementing wellbores, particularly oil and gas wellbores. Excellent fluid loss control is achieved over a wide range of conditions using various cements systems. The invention utilizes polyvinyl acetate polymers as a fluid loss additive. The polyvinyl acetate polymer is used in conjunction with a dispersing sulfonated polymer and surfactant. This highly effective combination is then adjusted to individual well conditions with chelating agent, cross-linking agent, biocides, antifoams, or combinations of these. The dispersants are novel dispersing agent polymers such as melamine sulfonate polymer, vinyl sulfonate polymer and styrene sulfonate polymer and mixtures of these. These dispersant materials are usually prepared at low pH and can be used in the acid form, or neutralized to form salts of the polymers, wherein the salt can be a Group I or Group II metal salt, or ammonium salts (common salts).

Abstract: Powdered and liquid fluid loss additives are disclosed for use in cementing wellbores, particularly oil and gas wellbores. Excellent fluid loss control is achieved over a wide range of conditions using various cements systems. The invention utilizes polyvinyl acetate polymers as a fluid loss additive. The polyvinyl acetate polymer is used in conjunction with a dispersing sulfonated polymer and surfactant. This highly effective combination is then adjusted to individual well conditions with chelating agent, cross-linking agent, biocides, antifoams, or combinations of these. The dispersants are novel dispersing agent polymers such as melamine sulfonate polymer, vinyl sulfonate polymer and styrene sulfonate polymer and mixtures of these. These dispersant materials are usually prepared at low pH and can be used in the acid form, or neutralized to form salts of the polymers, wherein the salt can be a Group I or Group II metal salt, or ammonium salts (common salts).