Abstract: A cement slurry may be separated from a drilling mud in a wellbore by introducing into the wellbore an aqueous fluid having a weighting agent, a hydratable gellant powder having a particle size distribution from about 150 to about 300 mesh; and a suspension agent of particulates of a resin encapsulated hydratable polymeric viscosifying agent, the suspension agent having a particle size distribution such that at least 90% of the particulates are retained on a 20 mesh screen and 100% of the particulates are retained on a 6 mesh screen. The weighting agent may be suspended in the viscous fluid by hydrating the hydratable gellant powder. At higher temperatures and after degradation of the hydrated gellant, the weighting agent remains suspended by degrading the resin of the suspension agent and releasing the hydratable polymeric viscosifying agent into the wellbore.

Abstract: The disclosure relates to a method of delaying viscosification of a well treatment fluid within a well by introducing into the well a cement slurry containing particulates of a hydratable viscosifying agent having a minimum of 90% retention on a 20 mesh screen. The presence of the hydratable viscosifying agent in the slurry prevents settling of the cement after the slurry is pumped into the well. The stability of the slurry is thus enhanced by the presence of the hydratable viscosifying agent.

Abstract: A spacer fluid contains one or more hydratable polymeric viscosifying agents having a particle size distribution such that a minimum of 90% of the particulates are retained on a 20 mesh screen. The spacer fluid may further contain one or more surfactants, viscosity thinners, organic solvents, weighting materials, suspending agents and antifoaming agents. The spacer fluid may be used to position a first fluid into a wellbore annulus of a wellbore containing a second fluid. The spacer fluid may further be used to fluidly isolate at least a portion of a wellbore annulus in a wellbore containing an oil-based drilling mud and an aqueous cement slurry.

Abstract: A cement slurry may be separated from a drilling mud in a wellbore by introducing into the wellbore an aqueous fluid having a weighting agent, a hydratable gellant powder having a particle size distribution from about 150 to about 300 mesh; and a suspension agent of particulates of a resin encapsulated hydratable polymeric viscosifying agent, the suspension agent having a particle size distribution such that at least 90% of the particulates are retained on a 20 mesh screen and 100% of the particulates are retained on a 6 mesh screen. The weighting agent may be suspended in the viscous fluid by hydrating the hydratable gellant powder. At higher temperatures and after degradation of the hydrated gellant, the weighting agent remains suspended by degrading the resin of the suspension agent and releasing the hydratable polymeric viscosifying agent into the wellbore.

Abstract: Curable resin compositions comprising an epoxy resin and a hydrazide curing agent and methods for using the curable resin compositions in cementing and/or remedial operations in a subterranean formation are provided. In one embodiment, the method may comprise combining an epoxy resin and a curing agent to form a curable resin composition, wherein the curing agent comprises a hydrazide curing agent; introducing the curable resin composition into a subterranean formation; and allowing the curable resin composition to at least partially cure.

Abstract: Disclosed herein are cement compositions and methods of using set-delayed cement compositions in subterranean formations. An embodiment includes a method of cementing in a subterranean formation comprising: providing a cement composition comprising water, pumice, hydrated lime, a set retarder, and a strength enhancer, wherein the strength enhancer comprises at least one material selected from the group consisting of cement kiln dust, slag, amorphous silica, a pozzolan, and any combination thereof; introducing the cement composition into the subterranean formation; and allowing the cement composition to set in the subterranean formation.

Abstract: Curable resin compositions comprising an epoxy resin and a hydrazide curing agent and methods for using the curable resin compositions in cementing and/or remedial operations in a subterranean formation are provided. In one embodiment, the method may comprise combining an epoxy resin and a curing agent to form a curable resin composition, wherein the curing agent comprises a hydrazide curing agent; introducing the curable resin composition into a subterranean formation; and allowing the curable resin composition to at least partially cure.

Abstract: Disclosed herein are cement compositions and methods of using set-delayed cement compositions in subterranean formations. An embodiment includes a method of cementing in a subterranean formation comprising: providing a cement composition comprising water, pumice, hydrated lime, a set retarder, and a strength enhancer, wherein the strength enhancer comprises at least one material selected from the group consisting of cement kiln dust, slag, amorphous silica, a pozzolan, and any combination thereof; introducing the cement composition into the subterranean formation; and allowing the cement composition to set in the subterranean formation.

Abstract: A spacer fluid contains one or more hydratable polymeric viscosifying agents having a particle size distribution such that a minimum of 90% of the particulates are retained on a 20 mesh screen. The spacer fluid may further contain one or more surfactants, viscosity thinners, organic solvents, weighting materials, suspending agents and antifoaming agents. The spacer fluid may be used to position a first fluid into a wellbore annulus of a wellbore containing a second fluid. The spacer fluid may further be used to fluidly isolate at least a portion of a wellbore annulus in a wellbore containing an oil-based drilling mud and an aqueous cement slurry.

Abstract: Disclosed herein are cement compositions and methods of using set-delayed cement compositions in subterranean formations. An embodiment includes a method of cementing in a subterranean formation comprising: providing a cement composition comprising water, pumice, hydrated lime, a set retarder, and a strength enhancer, wherein the strength enhancer comprises at least one material selected from the group consisting of cement kiln dust, slag, amorphous silica, a pozzolan, and any combination thereof; introducing the cement composition into the subterranean formation; and allowing the cement composition to set in the subterranean formation.

Abstract: The disclosure relates to a method of delaying viscosification of a well treatment fluid within a well by introducing into the well a cement slurry containing particulates of a hydratable viscosifying agent having a minimum of 90% retention on a 20 mesh screen. The presence of the hydratable viscosifying agent in the slurry prevents settling of the cement after the slurry is pumped into the well. The stability of the slurry is thus enhanced by the presence of the hydratable viscosifying agent.

Abstract: Disclosed herein are cement compositions and methods of using set-delayed cement compositions in subterranean formations. An embodiment includes a method of cementing in a subterranean formation comprising: providing a cement composition comprising water, pumice, hydrated lime, a set retarder, and a strength enhancer, wherein the strength enhancer comprises at least one material selected from the group consisting of cement kiln dust, slag, amorphous silica, a pozzolan, and any combination thereof; introducing the cement composition into the subterranean formation; and allowing the cement composition to set in the subterranean formation.