Methods of wellbore cementing are provided. A method of cementing may comprise calculating a lime to silica correlation for two or more cementitious components of a cement composition; and adjusting a concentration of at least one of the cementitious components such that the lime to silica correlation meets or exceeds a target.

Methods of wellbore cementing are provided. A method of cementing may comprise calculating a lime to silica correlation for two or more cementitious components of a cement composition; and adjusting a concentration of at least one of the cementitious components such that the lime to silica correlation meets or exceeds a target.

A green concrete and mortar compositions free of Portland cement are disclosed. The compositions comprise Natural pozzolan, nanosilica particles, and alkaline activator. The green concrete produced from the composition of the invention is cured at ambient temperature and has higher compressive strength than that of concrete made with Portland cement.

A green concrete and mortar compositions free of Portland cement are disclosed. The compositions comprise Natural pozzolan, nanosilica particles, and alkaline activator. The green concrete produced from the composition of the invention is cured at ambient temperature and has higher compressive strength than that of concrete made with Portland cement.

Three pumpable geopolymer compositions for well sealing application is disclosed herein. One pumpable geopolymer composition comprises: (i) less reactive aluminosilicate; (ii) more reactive aluminosilicate; (iii) alkaline silicate activator solution with a very low SiO.sub.2/M.sub.2O. Another pumpable geopolymer composition comprises: (i) less reactive aluminosilicate; (ii) more reactive aluminosilicate; (iii) alkaline silicate-free activator solution that may contain an alkali salt; and (iv) powdered alkali silicate glass. The third pumpable geopolymer composition comprises (i) less reactive aluminosilicate; (ii) more reactive aluminosilicate; (iii) alkaline low silicate activator solution; and (iv) powdered alkali silicate glass.

Three pumpable geopolymer compositions for well sealing application is disclosed herein. One pumpable geopolymer composition comprises: (i) less reactive aluminosilicate; (ii) more reactive aluminosilicate; (iii) alkaline silicate activator solution with a very low SiO.sub.2/M.sub.2O. Another pumpable geopolymer composition comprises: (i) less reactive aluminosilicate; (ii) more reactive aluminosilicate; (iii) alkaline silicate-free activator solution that may contain an alkali salt; and (iv) powdered alkali silicate glass. The third pumpable geopolymer composition comprises (i) less reactive aluminosilicate; (ii) more reactive aluminosilicate; (iii) alkaline low silicate activator solution; and (iv) powdered alkali silicate glass.

Cementing compositions containing a hydraulic cement, halloysite nanoparticles, and silica flour. The cementing compositions may optionally include other additives such as a friction reducer, a defoamer, and a fluid loss additive. Cement samples made therefrom and methods of producing such cement samples are also specified. The addition of halloysite nanoparticles and silica flour provides enhanced mechanical strength (e.g. compressive strength, flexural strength) and improved durability (e.g. resistance to CO.sub.2 and salinity) to the cement, making them suitable cementing material for oil and gas wells.

This invention relates to methods for servicing subterranean wells, in particular, fluid compositions and methods for remedial operations during which the fluid compositions are pumped into a wellbore and make contact with well cements placed during primary cementing or previous remedial cementing operations.

This invention relates to methods for servicing subterranean wells, in particular, fluid compositions and methods for remedial operations during which the fluid compositions are pumped into a wellbore and make contact with well cements placed during primary cementing or previous remedial cementing operations.

A method for continuous production of a thermally insulating mixture comprising silica particles and opacifier particles, in which a premixed stream comprising a carrier gas, silica particles and opacifier particles is introduced into a fine impact mill, ground and mixed therein, after which the solid is separated from the gas stream, wherein the fine impact mill is an air-stream mill comprising grinding tracks arranged one above the other on a rotatable shaft.