Described are cementitious reagent materials produced from globally abundant inorganic feedstocks. Also described are methods for the manufacture of such cementitious reagent materials and forming the reagent materials as microspheroidal glassy particles. Also described are apparatuses, systems and methods for the thermochemical production of glassy cementitious reagents with spheroidal morphology. The apparatuses, systems and methods make use of an in-flight melting/quenching technology such that solid particles are flown in suspension, melted in suspension, and then quenched in suspension. The cementitious reagents can be used in concrete to substantially reduce the CO.sub.2 emission associated with cement production.

Disclosed are a room temperature curable quick-setting high-strength alkali-activated fly ash (AAFA) cementitious material and a preparation method thereof, belonging to the technical field of building materials. The raw materials include: in parts by mass, 30-50 parts of undisturbed fly ash, 50-70 parts of highly reactive ultra-fine fly ash, and 12-18 parts of sodium hydroxide. Specifically, the AAFA with fast setting and high strength for room temperature curing is prepared by pretreatment of fly ash with sodium hydroxide exciter, based on a premise that the raw material system and preparation process are simplified and feasible.

Lithium-treated calcium aluminate cement (CAC)-based products, concretes, and related techniques are disclosed. In accordance with some embodiments, a lithium-treated CAC mixture may be produced by intergrinding ground-down CAC, class C fly ash, a lithium compound, and a polycarboxylate material. In accordance with some embodiments, a cementitious material may be produced by intergrinding said lithium-treated CAC mixture with class C fly ash, sodium citrate, and a polycarboxylate material. In accordance with some embodiments, a concrete may be produced by mixing said cementitious material (including said lithium-treated CAC mixture) with rock, sand, and water.

Systems and methods of the present invention include a method for the treatment of drilling wastes and coal combustion residues, comprising combining at least a first drilling waste with coal combustion residues to form a paste, combining at least a second drilling waste with coal combustion residues to form a compactable fill, and placing the paste and the compactable fill in a landfill. Other embodiments include a method of treating drilling wastes and coal combustion residues, comprising combining at least one drilling waste with a coal combustion residue to form a paste. Further embodiments include containing the paste within at least one geotextile container. Still further embodiments include placing the geotextile container in a landfill.

A downhole tool comprising a cylindrical housing, a sleeve disposed in the cylindrical housing, forming an annular space between the sleeve and the cylindrical housing, and a tool cement composition disposed in the annular space, wherein prior to setting the tool cement composition comprises a cement, sand, a silicon-containing material, a dispersant, and water, and wherein upon setting the tool cement composition provides an annular seal having a fluid leakage of less than 750 ml over 15 minutes at a pressure of 7500 psi and a temperature of 400° F.

A downhole tool comprising a cylindrical housing, a sleeve disposed in the cylindrical housing, forming an annular space between the sleeve and the cylindrical housing, and a tool cement composition disposed in the annular space, wherein prior to setting the tool cement composition comprises a cement, sand, a silicon-containing material, a dispersant, and water, and wherein upon setting the tool cement composition provides an annular seal having a fluid leakage of less than 750 ml over 15 minutes at a pressure of 7500 psi and a temperature of 400° F.

A downhole tool comprising a cylindrical housing, a sleeve disposed in the cylindrical housing, forming an annular space between the sleeve and the cylindrical housing, and a tool cement composition disposed in the annular space, wherein prior to setting the tool cement composition comprises a cement, sand, a silicon-containing material, a dispersant, and water, and wherein upon setting the tool cement composition provides an annular seal having a fluid leakage of less than 750 ml over 15 minutes at a pressure of 7500 psi and a temperature of 400° F.

A downhole tool comprising a cylindrical housing, a sleeve disposed in the cylindrical housing, forming an annular space between the sleeve and the cylindrical housing, and a tool cement composition disposed in the annular space, wherein prior to setting the tool cement composition comprises a cement, sand, a silicon-containing material, a dispersant, and water, and wherein upon setting the tool cement composition provides an annular seal having a fluid leakage of less than 750 ml over 15 minutes at a pressure of 7500 psi and a temperature of 400° F.

Devices and methods of recycling cement waste. A cement waste recycling device (1) comprising a heater (2) with an inlet (3) for cement waste and an outlet (4) for processed cement waste, wherein the heater (2) is configured for transporting cement waste in a cement waste transportation direction from the inlet (3) to the outlet (4) while transporting heated gas in countercurrent with the cement waste transportation direction.

Described are cementitious reagent materials produced from globally abundant inorganic feedstocks. Also described are methods for the manufacture of such cementitious reagent materials and forming the reagent materials as microspheroidal glassy particles. Also described are apparatuses, systems and methods for the thermochemical production of glassy cementitious reagents with spheroidal morphology. The apparatuses, systems and methods make use of an in-flight melting/quenching technology such that solid particles are flown in suspension, melted in suspension, and then quenched in suspension. The cementitious reagents can be used in concrete to substantially reduce the CO.sub.2 emission associated with cement production.