Embodiments relate to cementing operations and, in certain embodiments, to passivated cement accelerators and methods of using passivated cement accelerators in subterranean formations. An embodiment may comprise a method of cementing comprising: providing a cement composition comprising cement, water, and a passivated cement accelerator; and allowing the cement composition to set.

Embodiments relate to cementing operations and, in certain embodiments, to passivated cement accelerators and methods of using passivated cement accelerators in subterranean formations. An embodiment may comprise a method of cementing comprising: providing a cement composition comprising cement, water, and a passivated cement accelerator; and allowing the cement composition to set.

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.

A dry papercrete mix containing a pulp of fiber material such as newsprint and sharp sand, Portland cement and adding additional sand and/or pumice. The resulting dry, granular mix can then be handled stored and used in the manner which is conventional for concrete. The dry papercrete mix can be fortified with a fiber form of basalt which can be added to or substituted for all or a portion of the cellulose fiber content of the dry papercrete mix to provide a stronger structure when hydrated and cast into a desired shape with only a small increase in weight. Basalt reinforcing bars and meshes may be included in shapes cast from the hydrated mix in combination with or substitution for steel reinforcing structures. Including basalt in the mix and in reinforcing systems allows the design of joints between structural modules to provide exceptional strength in a unitary structure so formed.

A dry papercrete mix containing a pulp of fiber material such as newsprint and sharp sand, Portland cement and adding additional sand and/or pumice. The resulting dry, granular mix can then be handled stored and used in the manner which is conventional for concrete. The dry papercrete mix can be fortified with a fiber form of basalt which can be added to or substituted for all or a portion of the cellulose fiber content of the dry papercrete mix to provide a stronger structure when hydrated and cast into a desired shape with only a small increase in weight. Basalt reinforcing bars and meshes may be included in shapes cast from the hydrated mix in combination with or substitution for steel reinforcing structures. Including basalt in the mix and in reinforcing systems allows the design of joints between structural modules to provide exceptional strength in a unitary structure so formed.

Described are dry cast lightweight veneer blocks and a system and method of installing lightweight veneer blocks. The courses can be assembled without mortar between the courses. As an example, sides of the veneer blocks have areas that recede from an imaginary plane between adjacent veneer blocks to give a deep texturing and a shadow effect between veneer blocks. The installation system and method include a substrate, an air barrier applied to the substrate, a plurality of veneer blocks, and an adhesive applied between the plurality of veneer blocks and the air barrier.

Described are dry cast lightweight veneer blocks and a system and method of installing lightweight veneer blocks. The courses can be assembled without mortar between the courses. As an example, sides of the veneer blocks have areas that recede from an imaginary plane between adjacent veneer blocks to give a deep texturing and a shadow effect between veneer blocks. The installation system and method include a substrate, an air barrier applied to the substrate, a plurality of veneer blocks, and an adhesive applied between the plurality of veneer blocks and the air barrier.

Methods may comprise providing a cement dry blend comprising a plurality of cement particles and a plurality of inert microparticles, wherein the inert microparticles have an average diameter at least about 3 times smaller than that of the average diameter of the cement particles; mixing water, a set retarding additive, and the cement dry blend to yield a cement slurry; storing the cement slurry; mixing a cement set accelerator into the cement slurry; introducing the cement slurry into a wellbore penetrating a subterranean formation; and allowing the cement slurry to set at a location within the wellbore, the subterranean formation, or both.

Methods may comprise providing a cement dry blend comprising a plurality of cement particles and a plurality of inert microparticles, wherein the inert microparticles have an average diameter at least about 3 times smaller than that of the average diameter of the cement particles; mixing water, a set retarding additive, and the cement dry blend to yield a cement slurry; storing the cement slurry; mixing a cement set accelerator into the cement slurry; introducing the cement slurry into a wellbore penetrating a subterranean formation; and allowing the cement slurry to set at a location within the wellbore, the subterranean formation, or both.