A method for conditioning an acid waste by cementation, wherein the acid waste is chosen among liquids having a pH of no more than 4, semi-liquids having a pH of no more than 4, solids of which the partial or full dissolution in water leads to a solution or suspension having a pH of no more than 4, and mixtures thereof, which method comprises the steps of: a) preparing a cement paste having as components at least: a magnesium phosphate cement and the acid waste, and b) hardening the cement paste thus obtained, and is characterised in that in step a), the cement paste is prepared without subjecting beforehand the acid waste to any treatment consisting in reducing the acidity thereof.

A method for conditioning an acid waste by cementation, wherein the acid waste is chosen among liquids having a pH of no more than 4, semi-liquids having a pH of no more than 4, solids of which the partial or full dissolution in water leads to a solution or suspension having a pH of no more than 4, and mixtures thereof, which method comprises the steps of: a) preparing a cement paste having as components at least: a magnesium phosphate cement and the acid waste, and b) hardening the cement paste thus obtained, and is characterised in that in step a), the cement paste is prepared without subjecting beforehand the acid waste to any treatment consisting in reducing the acidity thereof.

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.

An anticorrosive composition and the use of the composition for imparting anticorrosive properties to a material such as a mineral wool product.

A spray material for hot and dry spray application with improved corrosion resistance, and a hot and dry spray application method with improved corrosion resistance. A hot and dry spray application method comprises pressure-feeding a mixture comprising a refractory material and a binder, toward a spraying nozzle via a pipe, and adding water to the mixture at a distal end of the spraying nozzle to apply a spray under a hot condition. The mixture contains magnesium limestone having a particle size of 0.075 mm to less than 1 mm, in an amount of 10 mass % to 50 mass %, in 100 mass % of a total amount of the refractory material and the binder. The content of magnesium limestone having a particle size of less than 0.075 mm in 100 mass % of the total amount of the refractory material and the binder is 35 mass % or less (including 0).

A spray material for hot and dry spray application with improved corrosion resistance, and a hot and dry spray application method with improved corrosion resistance. A hot and dry spray application method comprises pressure-feeding a mixture comprising a refractory material and a binder, toward a spraying nozzle via a pipe, and adding water to the mixture at a distal end of the spraying nozzle to apply a spray under a hot condition. The mixture contains magnesium limestone having a particle size of 0.075 mm to less than 1 mm, in an amount of 10 mass % to 50 mass %, in 100 mass % of a total amount of the refractory material and the binder. The content of magnesium limestone having a particle size of less than 0.075 mm in 100 mass % of the total amount of the refractory material and the binder is 35 mass % or less (including 0).

A spray material for hot and dry spray application with improved corrosion resistance, and a hot and dry spray application method with improved corrosion resistance. A hot and dry spray application method comprises pressure-feeding a mixture comprising a refractory material and a binder, toward a spraying nozzle via a pipe, and adding water to the mixture at a distal end of the spraying nozzle to apply a spray under a hot condition. The mixture contains magnesium limestone having a particle size of 0.075 mm to less than 1 mm, in an amount of 10 mass % to 50 mass %, in 100 mass % of a total amount of the refractory material and the binder. The content of magnesium limestone having a particle size of less than 0.075 mm in 100 mass % of the total amount of the refractory material and the binder is 35 mass % or less (including 0).

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.