Sorbent components containing halogen, calcium, alumina, and silica are used in combination during coal combustion to produce environmental benefits. Sorbents such as calcium bromide are added to the coal ahead of combustion and other components are added into the flame or downstream of the flame, preferably at minimum temperatures to assure complete formation of the refractory structures that result in various advantages of the methods. When used together, the components reduce emissions of elemental and oxidized mercury; increase the level of Hg, As, Pb, and/or Cl in the coal ash; decrease the levels of leachable heavy metals (such as Hg) in the ash, preferably to levels below the detectable limits; and make a highly cementitious ash product.

A concrete composition having an optimized formulation and suitable for 3-D printing is provided. The composition may include a hydraulic cement composition, aggregate, cement and/or aggregate by-product dust, one or more rheology modifiers, a plasticizer, fibers, and a sufficient amount of water to effect setting of the composition. Optionally the concrete composition may include a setting agent. A method for 3D printing multiple layers of the concrete composition is also provided.

A concrete composition having an optimized formulation and suitable for 3-D printing is provided. The composition may include a hydraulic cement composition, aggregate, cement and/or aggregate by-product dust, one or more rheology modifiers, a plasticizer, fibers, and a sufficient amount of water to effect setting of the composition. Optionally the concrete composition may include a setting agent. A method for 3D printing multiple layers of the concrete composition is also provided.

The disclosure relates to a method for controlling carbonation synthesis of silicon and/or aluminium carbonate minerals, wherein the concentration of dissolved silicon and/or aluminium in a mix to be cured is adjusted to at least 1 mmol/1 before curing he mix with gas comprising carbon dioxide (CO.sub.2) having a partial pressure of CO.sub.2 of at least 0.15 bar. In some embodiments of the isclosure an alkaline substance is added to the raw material to provide the mix where the total concentration of dissolved silicon and/or aluminium of at least 1 mmol/l. The disclosure also relates to a product obtainable by the methods of the disclosure as well as to the use of the product as building material, preferably for producing concrete-like products, more preferably for elements, most preferably for pre-casted elements and to the use of the method in construction industry or for production of elements and/or pre-casted elements.

The disclosure relates to a method for controlling carbonation synthesis of silicon and/or aluminium carbonate minerals, wherein the concentration of dissolved silicon and/or aluminium in a mix to be cured is adjusted to at least 1 mmol/1 before curing he mix with gas comprising carbon dioxide (CO.sub.2) having a partial pressure of CO.sub.2 of at least 0.15 bar. In some embodiments of the isclosure an alkaline substance is added to the raw material to provide the mix where the total concentration of dissolved silicon and/or aluminium of at least 1 mmol/l. The disclosure also relates to a product obtainable by the methods of the disclosure as well as to the use of the product as building material, preferably for producing concrete-like products, more preferably for elements, most preferably for pre-casted elements and to the use of the method in construction industry or for production of elements and/or pre-casted elements.

Methods of wellbore cementing are provided. A method of designing a cement composition may include: selecting a target heat of hydration for a target time and temperature; selecting one or more cementitious components and a weight percent for each of the one or more cementitious components such that a sum of a heat of hydration of the one or more cementitious components is less than or equal to the target heat of hydration; preparing the cement composition; and allowing the cement composition to set.

Methods of wellbore cementing are provided. A method of designing a cement composition may include: selecting a target heat of hydration for a target time and temperature; selecting one or more cementitious components and a weight percent for each of the one or more cementitious components such that a sum of a heat of hydration of the one or more cementitious components is less than or equal to the target heat of hydration; preparing the cement composition; and allowing the cement composition to set.

Expansive cements for use in cementing subterranean wells comprise water, an inorganic cement and one or more particulate materials that swell upon contact with a water immiscible fluid. The cements may further comprise a water immiscible fluid. Such cements are designed to seal microannuli arising from the presence of water immiscible fluids on casing surfaces, borehole wall surfaces or both.

Expansive cements for use in cementing subterranean wells comprise water, an inorganic cement and one or more particulate materials that swell upon contact with a water immiscible fluid. The cements may further comprise a water immiscible fluid. Such cements are designed to seal microannuli arising from the presence of water immiscible fluids on casing surfaces, borehole wall surfaces or both.

Cement compositions and associated methods for cementing. An example method includes introducing a cement composition into a wellbore penetrating a subterranean formation, the cement composition comprising a composite material, a cement, and an aqueous fluid. The composite material comprises a monophase amorphous hydraulic binder material and a particulate core. The monophase amorphous hydraulic binder material coats the particulate core. The method further comprises allowing the cement composition to set in the wellbore.