A method of reducing corrosion in tubular strings installed in wellbores includes dispensing an accelerated cement composition into a wellbore annulus, a casing-casing annulus, or both, the accelerated cement composition comprising a cement composition and an accelerant composition, where: the cement composition comprises a cement precursor and water; the accelerant composition comprises triethanolamine; and a concentration of the triethanolamine in the accelerated cement composition is greater than or equal to 10,000 parts per million by weight; allowing the accelerated cement composition to cure in the annulus to form a cured cement, where the triethanolamine reacts with a metal of the tubular string, the reaction forming a protective layer on the surfaces of the tubular string that inhibits dissolution of iron from the metal of the tubular string.

The present invention is directed to a biopolymer cement additive, a biopolymer cement composition containing the additive, the use of the additive for the production of, mortar or concrete and a process for the preparation of concrete or mortar implementing the biopolymer cement additive.

A red mud utilization method based on co-processing of industrial exhaust gas, sewage treatment and an environment-friendly and high-performance civil functional material, belongs to the technical field of environmental science and cementitious material preparation, and relates to a preparation process of a solid waste-based cementitious material, specifically including the steps: preparing an environment-friendly and high-performance red mud-based civil functional material by using slag obtained after sewage treatment with red mud and other solid wastes in physical and chemical activation and high-temperature calcination methods. The compressive strength of a solid waste-based cementitious material prepared by using the method can reach 29 MPa, the leaching quantity (lower than 3.0 ppm) of toxic elements such as heavy metals is far lower than the national standard requirement, and a solid waste-based cementitious material with great performance can be prepared.

A red mud utilization method based on co-processing of industrial exhaust gas, sewage treatment and an environment-friendly and high-performance civil functional material, belongs to the technical field of environmental science and cementitious material preparation, and relates to a preparation process of a solid waste-based cementitious material, specifically including the steps: preparing an environment-friendly and high-performance red mud-based civil functional material by using slag obtained after sewage treatment with red mud and other solid wastes in physical and chemical activation and high-temperature calcination methods. The compressive strength of a solid waste-based cementitious material prepared by using the method can reach 29 MPa, the leaching quantity (lower than 3.0 ppm) of toxic elements such as heavy metals is far lower than the national standard requirement, and a solid waste-based cementitious material with great performance can be prepared.

A manufacturing process of a cement product includes: (1) incorporating at least one additive into a high-alumina cement composition, wherein the at least one additive is selected from nitrate-containing salts, nitrite-containing salts, carbonate-containing salts, sulfate-containing salts, chloride-containing salts, and hydroxide-containing salts; and (2) curing the high-alumina cement composition to form the cement product.

A ready-mixed setting type joint compound in which formation of gypsum seeds has been inhibited. A method for controlling a setting reaction by mixing a ready-mixed setting type joint compound with one or more metal ion control agents comprising aminopolycarboxylic acid and/or a salt thereof, and further mixing the setting type joint compound with one or more non-calcium phosphate compounds. The method may further comprise mixing the setting type joint compound with a set activator obtained by blending together a first set activator including a cadmium compound, lead compound and/or zinc compound and a second set activator including a ferrous compound, aluminum compound and/or manganese compound.

A ready-mixed setting type joint compound in which formation of gypsum seeds has been inhibited. A method for controlling a setting reaction by mixing a ready-mixed setting type joint compound with one or more metal ion control agents comprising aminopolycarboxylic acid and/or a salt thereof, and further mixing the setting type joint compound with one or more non-calcium phosphate compounds. The method may further comprise mixing the setting type joint compound with a set activator obtained by blending together a first set activator including a cadmium compound, lead compound and/or zinc compound and a second set activator including a ferrous compound, aluminum compound and/or manganese compound.

A ready-mixed setting type joint compound in which formation of gypsum seeds has been inhibited. A method for controlling a setting reaction by mixing a ready-mixed setting type joint compound with one or more metal ion control agents comprising aminopolycarboxylic acid and/or a salt thereof, and further mixing the setting type joint compound with one or more non-calcium phosphate compounds. The method may further comprise mixing the setting type joint compound with a set activator obtained by blending together a first set activator including a cadmium compound, lead compound and/or zinc compound and a second set activator including a ferrous compound, aluminum compound and/or manganese compound.

A method of treating a lost circulation zone in a wellbore includes contacting an accelerant composition comprising triethanolamine with a cement composition in the lost circulation zone, the cement composition comprising at least: from 1 weight percent (wt. %) to 90 wt. % cement precursor based on the total weight of the cement composition; and from 5 wt. % to 70 wt. % water based on the total weight of the cement composition; where a weight ratio of triethanolamine to the cement precursor is from 0.1 percent (%) to 60%; and curing the cement composition in the lost circulation zone to form a cured cement, where the triethanolamine accelerates the curing rate of the cement composition and the cured cement seals the lost circulation zone.

A calcium sulphate-based product including gypsum and a shrinkage resistance additive. The shrinkage resistance additive is a metal nitrate, hydroxide, acetate or sulphate and is preferably provided in an amount greater than 4 wt % (based on the amount of additive and gypsum). The additive may be a nitrate of an alkali metal (e.g. potassium), an alkaline earth metal (e.g. magnesium or calcium), a transition metal (e.g. iron or zinc) or aluminium.