A high performance concrete composition comprising: (i) at least one Class C fly ash, (ii) at least one calcium aluminate cement, (iii) at least one aggregate, and (iv) water.

A high performance concrete composition comprising: (i) at least one Class C fly ash, (ii) at least one calcium aluminate cement, (iii) at least one aggregate, and (iv) water.

Some embodiments of the present invention comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, hydraulic cement, and water; and allowing the settable composition to set. Other embodiments comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, calcium hydroxide (lime), and water; and allowing the settable composition to set. Other embodiments comprise a settable composition comprising: remediated coal ash, hydraulic cement, calcium hydroxide, natural pozzolan and water; and allowing the composition to set. Other embodiments comprise a settable composition comprising remediated coal ash and any combination of hydraulic cement, calcium hydroxide, slag, fly ash, and natural or other pozzolan.

Some embodiments of the present invention comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, hydraulic cement, and water; and allowing the settable composition to set. Other embodiments comprise a method of cementing comprising: placing a settable composition into a well bore, the settable composition comprising remediated coal ash, calcium hydroxide (lime), and water; and allowing the settable composition to set. Other embodiments comprise a settable composition comprising: remediated coal ash, hydraulic cement, calcium hydroxide, natural pozzolan and water; and allowing the composition to set. Other embodiments comprise a settable composition comprising remediated coal ash and any combination of hydraulic cement, calcium hydroxide, slag, fly ash, and natural or other pozzolan.

Methods herein may include injecting a cement slurry having an aqueous base fluid, a cement, and a plurality of cellulose nanofibers dispersed in the aqueous base fluid. The plurality of cellulose nanofibers may be present in the slurry in an amount effective to provide a slurry density of not higher than 15 lb/gal.

Methods herein may include injecting a cement slurry having an aqueous base fluid, a cement, and a plurality of cellulose nanofibers dispersed in the aqueous base fluid. The plurality of cellulose nanofibers may be present in the slurry in an amount effective to provide a slurry density of not higher than 15 lb/gal.

A multifunctional cement additive includes a biochelant and a solvent. The biochelant includes a sodium glucarate liquid oxidation product including predominantly gluconate and glucarate anions with minor component species of n-keto-acids and C.sub.2-C.sub.5 diacids. A cement composition includes (i) a cementitious material and (ii) a biochelant, and (iii) a solvent. The biochelant includes a sodium glucarate liquid oxidation product including predominantly gluconate and glucarate anions with minor component species of n-keto-acids and C.sub.2-C.sub.5 diacids.

A multifunctional cement additive includes a biochelant and a solvent. The biochelant includes a sodium glucarate liquid oxidation product including predominantly gluconate and glucarate anions with minor component species of n-keto-acids and C.sub.2-C.sub.5 diacids. A cement composition includes (i) a cementitious material and (ii) a biochelant, and (iii) a solvent. The biochelant includes a sodium glucarate liquid oxidation product including predominantly gluconate and glucarate anions with minor component species of n-keto-acids and C.sub.2-C.sub.5 diacids.

A method includes adding an acidic salt of Iron (III) as additive to cement, mortar or concrete.

A method includes adding an acidic salt of Iron (III) as additive to cement, mortar or concrete.