Abstract: A cement slurry composition suitable for well bore cementation is provided containing as an essential component a synthetic hectorite clay in amount sufficient to reduce free water formation and solids segregation.

Abstract: Gas leakage from oil wells through casing thread connections and other small leakage spaces is reduced or eliminated by injecting into the lift gas flowstream a sealant composition comprising a carrier liquid, such as diesel fuel or water, an ethoxylated phenol surfactant and particulate silica and/or Gilsonite. A liquid sealant composition is injected into oil wells on artificial gas lift comprising arctic diesel fuel, a surfactant and solubilized Gilsonite in a weight ratio of about 10:1 diesel fuel to Gilsonite and diesel fuel to surfactant, respectively. Effective reduction in leakage flow rates is obtained over a relatively short time period (one to ten hours).

Abstract: What is disclosed is a method of accelerating the set of a retarded cement. The cement may range from a drilling fluid containing dispersants or retarders that will slow down the set of the drilling fluid when cementitious fluid is added thereto, through overwashing, or treating a retarded primary or remedial cement that may have been injected into fractures or areas within a well to overwashing a plug or any volume of retarded cement that needs to be set in a well.The specific uses are discussed.

Abstract: What is disclosed is a method of accelerating the set of a retarded cement. The cement may range from a drilling fluid containing dispersants or retarders that will slow down the set of the drilling fluid when cementitious fluid is added thereto, through overwashing, or treating a retarded primary or remedial cement that may have been injected into fractures or areas within a well to overwashing a plug or any volume of retarded cement that needs to be set in a well.The specific uses are discussed.