The present invention describes a hydraulic cement composition, its obtaining process and its use. More precisely, the hydraulic cement composition comprises increased resistance to CO.sub.2 for application in subsurface fluid reservoirs.

The present invention describes a hydraulic cement composition, its obtaining process and its use. More precisely, the hydraulic cement composition comprises increased resistance to CO.sub.2 for application in subsurface fluid reservoirs.

Hydrocarbon swelling particles for wellbore cementing include a crosslinked polymer comprising vinyl aromatic monomer and/or (meth)acrylic monomer.

Hydrocarbon swelling particles for wellbore cementing include a crosslinked polymer comprising vinyl aromatic monomer and/or (meth)acrylic monomer.

A cement composition is disclosed that includes a cement slurry and an epoxy resin system that includes at least one epoxy resin and a curing agent. The cement slurry has a density in a range of from 65 pcf to 180 pcf and includes a cement precursor material, silica sand, silica flour, a weighting agent, and manganese tetraoxide. The epoxy resin system includes at least one of 2,3-epoxypropyl o-tolyl ether, alkyl glycidyl ethers having from 12 to 14 carbon atoms, bisphenol-A-epichlorohydrin epoxy resin, or a compound having formula (I): (OC.sub.2H.sub.3)—CH.sub.2—O—R.sup.1—O—CH.sub.2—(C.sub.2H.sub.3O) where R.sup.1 is a linear or branched hydrocarbyl having from 4 to 24 carbon atoms; and a curing agent.

A cement composition is disclosed that includes a cement slurry and an epoxy resin system that includes at least one epoxy resin and a curing agent. The cement slurry has a density in a range of from 65 pcf to 180 pcf and includes a cement precursor material, silica sand, silica flour, a weighting agent, and manganese tetraoxide. The epoxy resin system includes at least one of 2,3-epoxypropyl o-tolyl ether, alkyl glycidyl ethers having from 12 to 14 carbon atoms, bisphenol-A-epichlorohydrin epoxy resin, or a compound having formula (I): (OC.sub.2H.sub.3)—CH.sub.2—O—R.sup.1—O—CH.sub.2—(C.sub.2H.sub.3O) where R.sup.1 is a linear or branched hydrocarbyl having from 4 to 24 carbon atoms; and a curing agent.

Cement slurries are prepared that comprise water, a hydraulic cement, particles of an oil-absorbent particles and non-swellable hydrophobic particles. The particles are present in an amount sufficient to alter a property of a non-aqueous drilling fluid. The cement slurry is placed in a subterranean well, whereupon the slurry contacts residual drilling fluid on casing and formation surfaces. The oil-absorbent particles and hydrophobic particles in the cement slurry may reduce the mobility of the drilling fluid, thereby improving zonal isolation.

Disclosed is an aqueous cementing slurry composition and a method of use thereof for cementing a pipe or casing in a borehole of a well using an aqueous cementing slurry composition comprising (a) a hydraulic cement, (b) a methylhydroxyethyl cellulose (HEMC) having an ethylene oxide molar substitution (EO MS) of from 0.16 to 0.22 and a methyl degree of substitution (M DS) of from 1.35 to 1.45, (c) water, and optionally (d) one or more other additives conventionally added to aqueous cementing compositions useful in cementing casings in the borehole of wells. Preferably, the aqueous cementing slurry composition is pumped downwardly into said casing, pumped upwardly into the annulus surrounding said casing until said aqueous composition fills that portion of the annular space desired to be sealed, and then maintaining said aqueous cementing composition in place until the cement sets.

Disclosed is an aqueous cementing slurry composition and a method of use thereof for cementing a pipe or casing in a borehole of a well using an aqueous cementing slurry composition comprising (a) a hydraulic cement, (b) a methylhydroxyethyl cellulose (HEMC) having an ethylene oxide molar substitution (EO MS) of from 0.16 to 0.22 and a methyl degree of substitution (M DS) of from 1.35 to 1.45, (c) water, and optionally (d) one or more other additives conventionally added to aqueous cementing compositions useful in cementing casings in the borehole of wells. Preferably, the aqueous cementing slurry composition is pumped downwardly into said casing, pumped upwardly into the annulus surrounding said casing until said aqueous composition fills that portion of the annular space desired to be sealed, and then maintaining said aqueous cementing composition in place until the cement sets.

A cement composition for use in a well that penetrates a subterranean formation comprising: cement; water; and an additive comprising zirconium dioxide, wherein at least a portion of the zirconium dioxide is in a metastable tetragonal phase, and wherein some or all of the zirconium dioxide that is in the metastable tetragonal phase transforms to a stable monoclinic phase after a stress is applied to the cement composition. The additive also reduces the dimensions of a crack located within the set cement composition. A method of cementing in a subterranean formation comprising: introducing a cement composition into the subterranean formation.