Abstract: A concrete building block containing Portland cement, a filler, water, and a quantity of particularly sized plastic particles, such as spent abrasive particles of a thermoset plastic. The associated method of producing such blocks eliminates the need of curing the blocks in a heated humidity controlled environment in order for the blocks to attain the required water content for hydration of the cement.

Abstract: A multiple mode cement set accelerating agent is provided. The accelerating agent includes a carrier fluid component having accelerator properties and CO2 gas sequestered in the carrier fluid. The accelerator components of the carrier fluid speed up the cement setting reaction. Additionally, CO2 gas is released from the carrier fluid during cement hydration to further accelerate the hydration reaction. In certain implementations, the carrier fluid is an alkanolamine solution and the cement set accelerating agent operates through a combination of alkali activation and carbonation. The multiple mode cement cure accelerating agent can be applied to pre-selected regions of green shaped cementitious articles to form partially cured zones in the article prior to curing of the green shaped article.

Abstract: Methods of cementing and low density foamed cement compositions therefor are disclosed. A low density foamed cement composition of the invention comprises fly ash comprising calcium oxide or calcium hydroxide, water present in an amount sufficient to form a slurry, a foaming and foam stabilizing surfactant or a mixture of surfactants present in an amount sufficient to facilitate foam and stabilize the foamed cement composition, and sufficient gas to foam the foamed cement composition.

Abstract: The present invention relates to oxidation-stable iron oxide pigments which have a coating of at least one organic substance, to their preparation and to their use.

Abstract: A method of treating fly ash and fly ash treated thereby, the method involving contacting ammonia-laden fly ash with an organic base-containing treatment composition, where the organic base causes the ammonia within the fly ash to evolve from the fly ash. The treatment composition preferably includes an effective amount of one or more amines. The treatment compound may be applied to the fly ash in any manner effective to disperse the treatment compound among the fly ash.

Abstract: A superior cement dispersant and a concrete composition containing the cement dispersant, the cement dispersant being a water-soluble amphoteric copolymer which contains an alkylene oxide adduct of a polyamide polyamine having an unsaturated group and at least two types of polyalkylene glycol ester. When the cement dispersant is compounded with a concrete composition, the dispersion performance thereof increases with time, and the concrete viscosity is effectively decreased. The cement dispersant composition contains a water-soluble amphoteric copolymer or the neutralized salt thereof as an essential component, which is obtained by copolymerizing an alkylene oxide adduct of a polyamide polyamine having an unsaturated group, (meta)acrylic acid or an alkali metal, ammonium, or alkanolamine salt thereof, an ester of an alkylene glycol and methacrylic acid, and an ester of an alkylene glycol and acrylic acid. In addition, the concrete composition containing the above cement dispersant is also disclosed.

Abstract: A liquid accelerator composition for sprayed concrete, comprising aluminium sulphate, amorphous aluminium hydroxide, alkanolamine and an organic dibasic acid anhydride. The compositions allow the attainment of high early compressive strength, and they can be tailored to give good performance with a wide variety of cement types.

Abstract: Methods of retarding the setting of a cement composition comprise including one or more secondary amines substituted with a carboxyl group or salts thereof (e.g., 3-hydroxy N,N?-iminodisuccinic acid) in the cement composition. The inclusion of such materials in cement compositions may be highly beneficial. In wellbores having BHCT's of less than or equal to about 250° F., the use of the secondary amine as the set retarder ensures that the thickening time of the cement composition is sufficient to allow the cement composition to be pumped to its desired downhole location. Further, the secondary amine may be used in combination with conventional set retarders to enhance the ability of those retarders to increase the thickening time of the cement composition at higher BHCT's, e.g., from about 250° F. to about 525° F.

Abstract: Subterranean fluids comprising a hydraulic cement in an invert emulsion, and methods of using such fluids in subterranean well cementing operations, are provided. The fluids comprise a hydraulic cement and an invert emulsion of oil, water, and a surfactant. Optionally, other ingredients may be included in the fluids.

Abstract: Methods and cement compositions for sealing a subterranean zone penetrated by a wellbore. The cement compositions include cementitious material, a mixing fluid, at least one polar monomer, and at least one elasticity enhancing monomer.

Abstract: Cement compositions are provided that comprise a hydraulic cement, water, and a set retarder composition, the set retarder composition comprising an acrylamide polymer derivative; and an iron compound. In some embodiments, cement compositions are provided that comprise a hydraulic cement comprising a cement, water, and a set retarder composition, the set retarder composition comprising a lignin-based retarder and an iron compound.

Abstract: The objective of the present invention is to provide a concrete composition in which the amount of air entrained can be maintained stably and which is excellent in strength and durability, a concrete composition which is excellent in freeze-thaw durability owing to the good quality of foams and is excellent in air content stability with time and which can form curing products excellent in strength and durability, a method of producing such concrete composition, and a cement admixture.

Abstract: A process for increasing the viscosity of an aqueous cementitious mixture during its working state by mixing oppositely-charge polyelectrolytes into the cementitious mixture.

Abstract: The subject of the present invention is the use of particular polysaccharides as admixtures for mineral materials, especially as admixtures for mineral binders. These polysaccharides have, characteristically: a weight-average molecular weight Mw of at least 500 g/mol and at most 9000 g/mol, especially between 700 and 7000 g/mol; and a degree of branching DB of at least 10%, especially between 10 and 40%. The invention also relates to the combined use, in mineral materials, including especially mineral binders, of these particular polysaccharides on the one hand and of certain other admixtures on the other hand, for example admixtures, of saccharidic or nonsaccharidic type, having a plasticizing, superplasticizing or other functionality.

Abstract: The present invention relates to pre-blend cement for general-purpose concrete construction containing Class-F fly ash, Class-C fly ash or slag, and less than about 5 percent (w/w) of sodium thiocyanate (NaSCN) and/or calcium nitrate (Ca(NO3)2), as a substantial replacement for cement. The sodium thiocyanate and/or calcium nitrate are additives for improved high early strength and accelerated setting times, thereby allowing the concrete structure to be put into service sooner, reducing labor cost, and allowing precast concrete and concrete masonry manufacturers to achieve rapid form and mold turnover.

Abstract: Cement compositions, that comprise water, a cement, a strength-retrogression additive, and an acid, wherein the acid comprises ethylenediamine tetra acetic acid, nitrilotriacetic acid, or a combination thereof, are provided. Methods of cementing in a subterranean formation, methods of retarding the set time of a cement composition, and set retarder compositions also are provided.

Abstract: The present invention relates to cementing operations, and more particularly to improved cement dispersants for cement compositions and methods of cementing. In one embodiment, the present invention provides a method of cementing comprising the steps of: providing a cement composition comprising a cement, and a dispersant composition, the dispersant composition comprising a surfactant and a hydrolyzed protein; placing the cement composition in a desired location; and allowing the cement composition to set.

Abstract: Exemplary compositions and methods for reducing hexavalent chromium in cementitious compositions involve the use of a liquid additive composition, comprising stannous chloride. Along with the stannous chloride may be used at least one co-additive comprising an antioxidant, oxygen scavenger, or mixture thereof, and/or at least one agent comprising a cement grinding aid, cement quality improver, or mixture thereof.

Abstract: An antimicrobial cementitious composition for imparting antimicrobial characteristics to cement comprises cement and an antimicrobial agent selected from the group consisting of an ortho-phenyl phenol or salt thereof, a tolyl diiodomethyl sulfone, a zinc pyrithione, an oxathiazine, an azole, a chlorothalonil, and a triazine diamine; combinations of agents also may be employed.

Abstract: An accelerator composition for use with sprayed cementitious compositions, which is an aqueous solution or dispersion of a blend of the essential Components 1–3 Component 1—aluminium sulphate Component 2—at least one of an alkanolamine and an alkylene diamine or triamine Component 3—hydrofluoric acid optionally with at least one of Components 4–7, with the proviso that at least one of Component 4 or Component 5 be present: Component 4—at least one of sodium hydroxide, potassium hydroxide, lithium hydroxide, magnesium hydroxide, lithium carbonate, sodium carbonate, potassium carbonate, magnesium carbonate, sodium sulphate, potassium sulphate, magnesium sulphate and lithium sulphate; Component 5—C1–C10 aliphatic mono- and dicarboxylic acids and their metal salts; Component 6—aluminium hydroxide; Component 7—at least one of phosphoric acid and phosphorous acid. The accelerators have excellent long-term stability and work well with “difficult” cements, such as some Japanese OPCs.

Abstract: An accelerator composition for use with sprayed cementitious compositions, which is an aqueous solution or dispersion of a blend of the essential Components 1–3 Component 1—aluminium sulphate Component 2—at least one of an alkanolamine and an alkylene diamine or triamine Component 3—hydrofluoric acid optionally with at least one of Components 4–7, with the proviso that at least one of Component 4 or Component 5 be present: Component 4—at least one of sodium hydroxide, potassium hydroxide, lithium hydroxide, magnesium hydroxide, lithium carbonate, sodium carbonate, potassium carbonate, magnesium carbonate, sodium sulphate, potassium sulphate, magnesium sulphate and lithium sulphate; Component 5—C1–C10 aliphatic mono- and dicarboxylic acids and their metal salts; Component 6—aluminium hydroxide; Component 7—at least one of phosphoric acid and phosphorous acid. The accelerators have excellent long-term stability and work well with “difficult” cements, such as some Japanese OPCs.

Abstract: The present invention is directed to hydraulic cement compositions comprising set-retarding additives and methods of retarding the set of a cement composition utilizing poly(amide) set-retarding additives and methods of cementing in subterranean zones utilizing a cement composition comprising a poly(amide) set-retarding additive.

Abstract: An exemplary method of the invention comprises introducing into a grinding mill, wherein cement clinker is ground to provide cement powder, a diamine such as tetrahydroxylethylethylene diamine, and an alkanolamine such as triethanolamine or triisopropanolamine. The combination of the diamine and alkanolamine provides superior grinding efficiency compared to diamine or alkanolamine added separately.

Abstract: An in situ ionic interaction between two additives, one a cationic strength enhancing additive and one an anionic crosslinking additive, is used to improve the mechanical properties of an article formed from a composite material. The composite has a discrete phase bound together with a film of the additives, such as gypsum crystals bound together by a film of substituted starch or cellulose ether.

Abstract: The present invention provides a cement composition and a process for using the cement composition to inhibit gas migration from a subterranean zone into the cement. The process comprises displacing a gelling additive, preferably comprised within a cement composition, into a well bore such that the gelling additive passes into the subterranean zone, and allowing the gelling additive to form a crosslinked gel in the subterranean zone to inhibit gas migration from the subterranean zone. The crosslinked gel acts as a barrier to gas in the subterranean zone and thereby inhibits the gas from passing into the cement and forming flow channels therein before the cement can set.

Abstract: A composition and method for repairing metal reinforced concrete structures by applying a repair coating to surfaces of such damaged structures. The coating composition is a mortar/aggregate mixture blended with fiber reinforcements and containing a quantity of selected migratory corrosion inhibitors. These inhibitors are a mixture of sodium gluconate together with an auxiliary inhibitor consisting of sodium sebacate, potassium sebacate or ammonium benzoate. The fiber reinforcements consist of polypropylene or polyethylene, and are co-extruded with a quantity of the migratory corrosion inhibitors listed above.

Abstract: The present invention relates to methods of stimulating a subterranean formation. More particularly, but not by way of limitation, the present invention relates to methods of fracturing subterranean formations utilizing a fracturing fluid comprising a permeable cement composition that may be used as a propping agent. One method of stimulating a subterranean formation of the present invention comprises the following steps: preparing a permeable cement composition comprising a hydraulic cement, water, and a degradable material capable of undergoing an irreversible degradation downhole; injecting the permeable cement composition into the subterranean formation at a pressure sufficient to create a fracture in the subterranean formation; and allowing the permeable cement composition to form a proppant matrix having voids in the fracture.

Abstract: An alkali-free accelerator for use with spray-applied cementitious compositions such as concrete and mortar is the reaction product in aqueous medium of amorphous aluminium hydroxide, aluminium sulphate, formic acid and phosphoric acid. These accelerators perform as well as known alkali-free accelerators and are exceptionally stable, even in hot conditions.

Abstract: This invention relates to improved methods for completing wells in unconsolidated subterranean zones. More specifically, the present invention relates to cement compositions useful in subterranean applications, and more particularly, to permeable cement compositions and methods for forming consolidated permeable cement masses in well bores to prevent sand influx into the well bores with produced fluids. In one embodiment, the permeable cement compositions of the present invention comprise a hydraulic cement, water, and a degradable material capable of undergoing an irreversible degradation downhole.

Abstract: The mechanical property known as “strength at young ages” of cement matrices or hydraulic binders may be significantly improved by adding dispersions of mineral fillers and dispersing agents. The dispersing agents of the present invention comprise copolymers prepared by the radical copolymerization of at least one alkoxy-, aryloxy-, alkylaryloxy- or arylalkyloxy-polyalkylene glycol ethylenic urethane monomer with at least one anionic monomer and at least one non-ionic monomer, and optionally, an alkoxy-, aryloxy-, alkylaryloxy- or arylalkyloxy-polyalkylene glycol acrylate or methacrylate or an alkyloxy-, aryloxy-, alkylaryloxy- or arylalkyloxy-polyalkylene glycol allyl ether, and/or a crosslinking agent.

Abstract: The present invention provides improved cement compositions comprising hydraulic cement, silica hydrophobicized with a mixture of organosilicon compounds and water.

Abstract: Fiber reinforced lightweight concrete composites employ less than 4% by volume of reinforcing fibers in conjunction with small particulate lightweight aggregates or voids, and cure to composites which exhibit high tensile strain and strain hardening behavior. The composites are useful for numerous structures in civil engineering.

Abstract: Cements or hydraulic binders may be prepared by adding an aqueous suspension comprising a ground mineral filler and at least one grinding aid agent to a cement or hydraulic binder. The resulting cement or hydraulic binder has very appreciably improved mechanical properties, particularly the property of “strength at young ages.” The grinding aid agent may be a natural or synthetic homopolymer and/or copolymer.

Abstract: Methods of cementing subterranean zones using cement compositions containing biogradable dispersants are provided. The methods are basically comprised of the steps of preparing a hydraulic cement, a biodegradable dispersant comprised of polyaspartic acid containing side chains formed by reacting one or more side chain chemicals with said polyaspartic acid and sufficient water to form a pumpable slurry, placing the cement composition into a zone to be cemented and allowing the cement composition to set into an impermeable solid mass therein.

Abstract: The present invention provides a cement admixture that comprises at least one of a carboxylic acid based copolymer comprising a reactive surfactant as a monomer or a copolymer salt obtained by neutralizing the copolymer with an alkaline substance, a method for preparing the same, and a cement composition comprising the same. The cement admixture of the present invention increases composition fluidity even at a high water-reducing formulation by improving dispersibility of cement particles, prevents a decrease of fluidity as the function of time, and offers good workability by supplying an adequate amount of air flow continuously.

Abstract: The admixtures for a cementitious composition of the invention, which have the above-mentioned constitutions, can suitably be used in cement pastes, mortar, concrete and like cement compositions and can stabilize the amount of air entrained with the lapse of time and thus facilitate the quality control of cement compositions and, further, can improve the workability of cement compositions owing to their excellent dispersing capacities. The cement compositions of the invention which comprise such admixture for a cementitious composition are excellent in water-reducing ability and workability and can give hardened products excellent in strength and durability and, further, can stably maintain the amount of air entrained without allowing increases in the amount of air even when the time of kneading is prolonged in the production.

Abstract: Exemplary compositions comprise at least one aldopentonic acid, such as xylonic acid; and further comprise a lignin, a lignosulfonic acid or its salt, an additional sugar acid such as a aldohexonic acid or salt, a conventional admixture (such as a polyacrylate superplasticizer, a corrosion inhibitor, a set retard, a set accelerator, etc.), or a mixture thereof. Exemplary methods for obtaining microbiologically or enzymatically converted sugar acids are also described herein.

Abstract: Methods of cementing subterranean zones penetrated by well bores using cement compositions having enhanced compressive strengths are provided. A method of the invention basically comprises the steps of preparing or providing a cement composition having enhanced compressive strength upon setting comprising a hydraulic cement, sufficient water to form a slurry and a hydroxyamine compressive strength enhancing additive. Thereafter, the cement composition is placed in a subterranean zone to be cemented and allowed to set into an impermeable solid mass therein.

Abstract: The invention concerns the use of water-soluble polysaccharide derivatives as dispersing agents for mineral binder suspensions. A partially hydrolyzed cellulose containing carboxyl groups and optionally hydroxyalkyl and/or sulfate groups and/or a partially hydrolyzed amylose-rich starch which also has sulfoalkyl groups with 1 to 4 carbon atoms is used as the polysaccharide derivative. These polysaccharide derivatives have a low viscosity and an excellent plasticizing effect in mineral binder suspensions, especially in those based on cement, lime and/or gypsum.

Abstract: Methods and compositions involving hexavalent chromate-reducing agents, particularly hydroxylamine, hydrazine, or their salts or derivatives, for use in cement compositions and cement processing.

Abstract: Extremely fast setting of cementitious compositions for producing cement-based products such as cement boards is made possible by adding an alkanolamine to a hydraulic cement such as portland cement, and forming a slurry with water under conditions that provide an initial slurry temperature of at least 90° F. Use of alkanolamine under conditions disclosed herein allows an extremely rapid setting of the cementitious composition. Additional reactive materials may be included such as high alumina cement, calcium sulfate and a pozzolanic material such as fly ash. The extremely fast rapid set permits rapid production of cementitious products.

Abstract: A high early-strength cementitious composition comprising a hydraulic cement; and a combination admixture system wherein the combination admixture system comprises a polycarboxylate high range water reducing dispersant in combination with an accelerator and a retarder. The admixture allows for acceptable workability and development of high early-strength in cementitious compositions without the use of an external heat source.

Abstract: An exemplary admixture system for cementitious compositions, comprises a polycarboxylic acid type water reducer and a tertiary amine defoamer having an average molecular weight of 100-1500 and more preferably 200-750. The defoamer permits a stable admixture formulation and helps to achieve a controllable level of entrained air in a concrete mix. Cementitious compositions and methods for modifying the same, using the tertiary amine defoamers, are also described herein.

Abstract: A cement composition is basically comprised of a hydraulic cement, water in an amount sufficient to form a pumpable slurry and a fluid loss control polymer additive comprised of 69 weight % of the calcium salt of 2-acrylamido-2-methyl propane sulfonic acid, 14 weight % of the calcium salt of maleic acid, 14 weight % of N-vinyl caprolactam and 3 weight % of 4-hydroxybutyl vinyl ether.

Abstract: A cement composition for liquid casting, based on a binder comprising Portland cement and additives comprising at least a fluidizer and a combination of a thickening agent acting by steric exclusion and a gelling thickening agent. The composition can also include a surface active agent to regulate the quantity of entrained air. Mixed with water and an aggregate, it permits obtaining, in a single casting, a self-leveling casting of a high thickness (equal to at least 6 cm) and of low density (about 1.6 to 1.9).

Abstract: The present invention relates to cementing operations, and more particularly, to cement compositions comprising set retarder compositions and methods of using the cement compositions in surface and subterranean applications. In some embodiments, the present invention provides cement compositions that comprise a hydraulic cement comprising an API cement, water, and a set retarder composition, the set retarder composition comprising an acrylamide polymer derivative; and an iron compound. In other embodiments, the present invention provides cement compositions, set retarder compositions, methods of cementing, methods of retarding the set time of a cement composition, and methods of preparing a cement composition.

Abstract: This invention relates to improved methods for completing wells in unconsolidated subterranean zones. More specifically, the present invention relates to cement compositions useful in subterranean applications, and more particularly, to permeable cement compositions and methods for forming consolidated permeable cement masses in well bores to prevent sand influx into the well bores with produced fluids. In one embodiment, the permeable cement compositions of the present invention comprise a hydraulic cement, water, and a degradable material capable of undergoing an irreversible degradation downhole.

Abstract: An improved method of cementing casing in a deep water offshore formation penetrated by a well bore comprising the steps of preparing a foamed cement composition comprised of calcium aluminate cement, a set accelerating additive, a thickening time increasing additive, water, a gas, and a mixture of foam forming and foam stabilizing surfactants; placing the cement composition in the annulus between the casing and well bore; and allowing the cement composition to set into a hard impermeable mass therein.

Abstract: The invention relates to an accelerator used for setting and hardening and a method for accelerating and hardening hydraulic binding agents using said accelerator. The principal components of said accelerator are nitrates, aminoalcohols, hydroxycarboxylic acids and polyalcohols. The hardening acceleration is not connected with a rapid loss in processability, which is common in other accelerated systems.

Abstract: An additive for use in aqueous cement slurries which adapted such that, when added to an aqueous cement slurry, it migrates to an interface between the slurry and an adjacent solid material or fluid composition during a setting phase of the cement because of the passing of the upper limit of solubility in the water of the additive.