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.

A novel engineered concrete binder composition providing overall reduced clinker factor and improved binding properties. The said concrete binder composition includes a primary binder in a ratio of 10-60 weight percent and a secondary binder in a ratio of 40-90 weight percent. The said primary binder is selected from a primary material group having spontaneous hydration property. The said secondary binder is selected from a secondary material group having induced hydration property.

A novel engineered concrete binder composition providing overall reduced clinker factor and improved binding properties. The said concrete binder composition includes a primary binder in a ratio of 10-60 weight percent and a secondary binder in a ratio of 40-90 weight percent. The said primary binder is selected from a primary material group having spontaneous hydration property. The said secondary binder is selected from a secondary material group having induced hydration property.

Disclosed herein are methods and compositions for cementing. An example method may comprise providing a cement composition. The cement composition may comprise a composite cementitious material comprising a micronized particulate solid and a monophase amorphous hydraulic binder. The micronized particulate solid may have a mean particle size of about 500 microns or less. The cement composition may further comprise water. The method may further comprise introducing the cement composition into a subterranean formation; and allowing the cement composition to set.

Disclosed herein are methods and compositions for cementing. An example method may comprise providing a cement composition. The cement composition may comprise a composite cementitious material comprising a micronized particulate solid and a monophase amorphous hydraulic binder. The micronized particulate solid may have a mean particle size of about 500 microns or less. The cement composition may further comprise water. The method may further comprise introducing the cement composition into a subterranean formation; and allowing the cement composition to set.

Methods of recovering coal combustion products (CCPs) from coal combination byproducts are disclosed. The methods include compiling coal combustion byproducts (e.g., lignite coal and/or bituminous coal), grinding the coal combustion byproducts to form ground coal combustion byproducts with a maximum particle size of 40 microns, and separating the ground coal combustion byproducts to yield CCPs using an electrostatic precipitator. The following CCPs can be separated from the coal combination byproducts using the presently disclosed methods: fly ash, bottom ash, scrubber materials, and raw coal.

Methods of recovering coal combustion products (CCPs) from coal combination byproducts are disclosed. The methods include compiling coal combustion byproducts (e.g., lignite coal and/or bituminous coal), grinding the coal combustion byproducts to form ground coal combustion byproducts with a maximum particle size of 40 microns, and separating the ground coal combustion byproducts to yield CCPs using an electrostatic precipitator. The following CCPs can be separated from the coal combination byproducts using the presently disclosed methods: fly ash, bottom ash, scrubber materials, and raw coal.

A variety of systems, methods and compositions are disclosed, including, in one method, a method of cementing may comprise: providing a cement composition comprising: a hydraulic cement comprising Portland cement in an amount of about 50% by weight of hydraulic cement or less, water, and a phosphorylated amino polycarboxylic acid cement retarder; placing the cement composition in a wellbore; and allowing the cement composition to set. A cement composition, the composition comprising: a hydraulic cement comprising Portland cement in an amount of about 50% by weight of hydraulic cement or less; water; and a phosphorylated amino polycarboxylic acid cement retarder.

A variety of systems, methods and compositions are disclosed, including, in one method, a method of cementing may comprise: providing a cement composition comprising: a hydraulic cement comprising Portland cement in an amount of about 50% by weight of hydraulic cement or less, water, and a phosphorylated amino polycarboxylic acid cement retarder; placing the cement composition in a wellbore; and allowing the cement composition to set. A cement composition, the composition comprising: a hydraulic cement comprising Portland cement in an amount of about 50% by weight of hydraulic cement or less; water; and a phosphorylated amino polycarboxylic acid cement retarder.

Methods and systems of reducing lost circulation in a wellbore are provided. An example method includes providing a pozzolan slurry comprising a pozzolanic material and water; and providing a calcium slurry comprising a calcium source, a high pH activator, and water. The method further comprises allowing the pozzolan slurry and the calcium slurry to remain separate; wherein at least one of the pozzolan slurry and the calcium slurry comprise a thixotropic material; wherein at least one of the pozzolan slurry and the calcium slurry comprise a dispersant; wherein at least one of the pozzolan slurry and the calcium slurry comprise a weighting agent. The method additionally comprises mixing the pozzolan slurry and the calcium slurry to form a two-part thixotropic lost circulation slurry after the allowing the pozzolan slurry and the calcium slurry to remain separate. The method also includes introducing the two-part thixotropic lost circulation slurry to a lost circulation zone within the wellbore; and allowing or causing to allow the two-part thixotropic lost circulation slurry to set into a hardened mass within the lost circulation zone.