An ultra-high temperature resistant cement slurry system comprising cement, an ultra-high temperature strength stabilizer, an ultra-high temperature reinforcing material, a density regulator, an ultra-high temperature suspension stabilizer, a dispersant, a fluid loss additive, a retarder, a defoaming agent and water, wherein the ultra-high temperature suspension stabilizer comprises an ether-based starch, an aluminosilicate and a polyalcohol polymer. The method for preparing the cement slurry system includes dry mixing and wet mixing raw materials homogeneously, respectively, and then homogeneously mixing the dry mix and wet mix to obtain the cement slurry system. The cement slurry system can be used for cementing in deep wells and ultra-deep wells at high and ultra-high temperatures.

The invention relates to a refractory dry vibratable mix which sets at room temperature when water is added, for use in metallurgical vessels and comprising a refractory main component, a binder and a retarder.

A lightweight aggregate-based non-steam-cured high-performance pipe culvert and a preparation method thereof. The lightweight aggregate-based non-steam-cured high-performance pipe culvert is prepared from a raw material including the following components by mass per unit volume: 300-450 kg/m.sup.3 of a low-carbon sulfur-aluminum-ferric cementitious material; 800-920 kg/m.sup.3 of a solid waste-based lightweight aggregate; 300-550 kg/m.sup.3 of a solid waste-based artificial sand; 0-100 kg/m.sup.3 of a mineral admixture; 0-50 kg/m.sup.3 of an auxiliary material; and 110-160 kg/m.sup.3 of water; and the lightweight aggregate-based non-steam-cured high-performance pipe culvert further includes a water reducer and a retarder. The lightweight aggregate-based non-steam-cured high-performance pipe culvert of the present invention can be demolded within 4 hours during forming, with short demolding time and no need for steam curing, resulting in a low production cost and high production efficiency. The obtained product has high strength, good impermeability and durability, and can utilize solid waste in a high proportion.

A high-thermal conductivity grout composition is provided. The composition includes a grout mixture including a cementitious material, a retarder, and a high-thermal k material that advantageously can form a pumpable slurry upon admixture with water. The retarder is present in an amount effective that delays setting of the grout mixture at a target location having a geostatic target temperature of at least 300 F. for at least two hours. The high-thermal k material is present in an amount effective such that the grout mixture has, upon setting at the target location, a thermal conductivity of at least 1 W/m K.

The present disclosure relates to cement compositions including Portland cement and volcanic ash. An exemplary cement composition includes about 10 wt % to about 85 wt % of Portland cement, and about 10% by weight of cement (BWOC) to about 70% BWOC of volcanic ash.

Geopolymeric compositions are presented that are useful as geopolymer slurries for cementing subterranean wells. The slurries may contain an aluminosilicate source, an alkaline source, and a carrier fluid. The slurries generate an alkali metal or alkaline earth hydroxide activator in situ, thereby avoiding or reducing handling of alkali materials at a wellsite.

Cementitious compositions comprising lime, which may be foamed or non-foamed compositions, may increase carbon dioxide uptake of the cementitious compositions. Said cementitious compositions may be used in various cementing methods including pre-casting methods, cast-in-place methods, and primary or secondary cementing operations in a wellbore. The carbon dioxide may be added to the cementitious compositions during mixing, during pre-conditioning, during curing, or any combination thereof. Further, the carbon dioxide may be delivered as a gas (e.g., a gas that includes 1 vol % to 100 vol % carbon dioxide) or as a gas-entrained admixture that includes the gas, water, and a foaming agent.