Abstract: Black powder flowing with hydrocarbons in a hydrocarbon pipeline is converted into a magnetorheological slurry by implementing wet scrubbing in the hydrocarbon pipeline. A flow of the magnetorheological slurry through the hydrocarbon pipeline is controlled.

Abstract: Black powder flowing with hydrocarbons in a hydrocarbon pipeline is converted into a magnetorheological slurry by implementing wet scrubbing in the hydrocarbon pipeline. A flow of the magnetorheological slurry through the hydrocarbon pipeline is controlled.

Abstract: The present invention provides a novel method for producing hydrogen fluoride, which is capable of using various calcium fluoride sources and preventing a second pasty state from occurring, effectively. In a method for producing hydrogen fluoride by reacting calcium fluoride with sulfuric acid, following steps are conducted: (a) a step for mixing and reacting calcium fluoride particles having an average particle diameter of 1-40 ?m with sulfuric acid at a sulfuric acid/calcium fluoride molar ratio of 0.9-1.1 under a temperature of 0-70° C. to obtain a solid-state reaction mixture; and (b) a step for heating the solid-state reaction mixture to a temperature of 100-200° C. to react with itself, and thereby producing hydrogen fluoride in a gas phase.

Abstract: The present invention relates to a foamed or non-foamed stable composition for use as a building material, for example as coverings, for plastering and insulating walls, floor slabs and ceilings. Such compositions can also be used for producing insulating structural elements, casting light and insulating ferro-cement structural systems, insulating piping, ducts, filling spaces (i.e. as fillers), stabilizing floors and producing cements floors, or for other uses in the constructions industry. One exemplary composition comprises the following components: 30 to 90% anhydrite, 0 to 40% Portland cement, 0 to 70% light and/or heavy fillers, 1 to 10% activator additives, 1 to 20% setting and strength regulator additives and 1 to 12% thickening additives.

Abstract: Hydraulic binder comprising: at least one first calcium aluminosilicate derivative with a fineness of less than 6000 Blaine, slag microparticles with a fineness of greater than or equal to 6000 Blaine in an amount of between 1 and 35% of the total weight of the binder, preferably of between 5 and 15%, at least one source of calcium sulphate and at least one base in an amount of less than or equal to 1% of the total weight of the binder.

Abstract: Provided are plaster patching compositions including lime, sand, perlite and gypsum. Also provided are methods of making and using the compositions to reproduce, preserve, and/or repair plaster, for example, historic plaster.

Abstract: A wallboard, a method of preparing a wallboard, and a method of making a gypsum slurry to prepare a wallboard are provided. The wallboard includes a set gypsum dihydrate derived substantially from a non-fibrous form of calcium sulfate and selected from the group consisting of anhydrous gypsum and gypsum hemihydrate. The wallboard also includes an aerogel dispersed in the gypsum dihydrate.

Abstract: The invention provides a cement admixture that improves the ability of concrete to bring about high initial strength, works in favor of enhancing the effect on hexavalent chromium reductions, and is less likely to decrease in the effect on hexavalent chromium reductions even upon storage as well as a method for reducing hexavalent chromium. The invention is embodied as (1) A cement admixture, characterized by comprising an expanding material containing free lime, a hydraulic compound and calcium sulfate anhydrite, and a tin sulfate-containing substance; (2) The cement admixture according to (1), characterized in that the tin sulfate-containing substance is contained in an amount of 0.

Abstract: Provided are methods and systems for introducing a wet gypsum accelerator or other high viscosity production additive to an aqueous dispersion of calcined gypsum in a discharge apparatus downstream of a stucco mixer in which the dispersion was prepared. These methods and systems are useful in the production of various gypsum products such as board including wallboard and ceiling tiles.

Abstract: A method of servicing a wellbore in a subterranean formation, comprising preparing a cement composition comprising water and a cementitious material, wherein the cementitious material further comprises blast furnace slag, vitrified shale, calcium sulfate hemi-hydrate or combinations thereof, and placing the cement composition in the wellbore. A cement composition comprising water and a cementitious material, wherein the cementitious material further comprises blast furnace slag, vitrified shale, calcium sulfate hemi-hydrate or combinations thereof. A cement composition comprising water and a cementitious material, wherein the cementitious material further comprises blast furnace slag.

Abstract: In a first embodiment of the invention, aged brushite is combined with calcium sulfate hemihydrate and water to make a gypsum slurry. Aged brushite slurry behaves similarly to calcium sulfate dihydrate to act as a seed crystal and rapidly initiate crystallization. The brushite slurry does not require the addition of a coating to maintain its activity over time compared to calcium sulfate dihydrate set accelerators. A gypsum-based product made using brushite slurry as the set accelerator is a second embodiment. The product has the brushite molecules integrated as part of the calcium sulfate dihydrate matrix and is distributed throughout the matrix.

Abstract: Light structural mortar compositions containing light loads, type II synthetic anhydrite and additives and methods for the production and use thereof are disclosed and described. Such compositions may be useful for application in ferro-cement constructive systems in order to provide thermal, acoustic and anti-seismic characteristics desirable for coating on interior and exterior walls and ceilings/roofs, as a substitution of cement-based mortar.

Abstract: The present invention relates in general to implantable compositions, and method for preparing same, containing a calcium salt-containing component, optionally demineralized bone, a plurality of discrete fibers, optionally a flow additive, and optionally continuous reinforcing fibers or an array of organized fibers in the form of mesh. Advantageously, the discrete fibers have a specific aspect ratio (length/diameter) from about 50:1 to about 1000:1. The addition of a small amount of discrete fibers and/or the continuous reinforcing fibers or fiber mesh can cause drastic increases in certain mechanical properties including flexural strength, flexural toughness, and/or screw pullout strength.

Abstract: Provided are methods and systems for introducing a wet gypsum accelerator or other high viscosity production additive to an aqueous dispersion of calcined gypsum in a discharge apparatus downstream of a stucco mixer in which the dispersion was prepared. These methods and systems are useful in the production of various gypsum products such as board including wallboard and ceiling tiles.

Abstract: Light structural mortar compositions containing light loads, type II synthetic anhydrite and additives and methods for the production and use thereof are disclosed and described. Such compositions may be useful for application in ferro-cement constructive systems in order to provide thermal, acoustic and anti-seismic characteristics desirable for coating on interior and exterior walls and ceilings/roofs, as a substitution of cement-based mortar.

Abstract: A gypsum stucco composition comprising the following components finely divided; calcium sulphate hemihydrate in calcined solid beta crystalline form; and in intimate mixture with said finely divided calcium sulphate hemihydrate and mixed therewith no later than calcination to form the hemihydrate, a sulphate salt comprising at least one of ammonium sulphate and aluminium sulphate, in an amount such that when the stucco composition is mixed with water and allowed to set, the resulting set plaster has increased compressive strength, flexural strength and/or E-modulus compared to a set plaster produced from said finely divided calcium sulphate hemihydrate containing no said sulphate salt.

Abstract: Method and apparatus for converting wet synthetic gypsum from a flue desulphurization process (FGD) to easily handled and metered briquettes by mixing a hydraulic additive such as by-pass dust from a cement kiln with synthetic gypsum and allowing the heat from the resulting hydraulic reaction to reduce the water content of the mixture to a formable consistency without adding external heat to the mixture as it is formed into briquettes.

Abstract: A composition and method for forming a composite material comprising a mixture of component A and component B, component A comprising gypsum and an inhibitor; and component B comprising an accelerator, wherein at least one of component A and component B further comprises a polymer binder having a Tg of below ?23° C. or wherein the Shore D hardness of the composite material when cured is less than 70; the method comprising providing a first slurry mixture of component A and a second slurry mixture of component B and blending the first slurry mixture and the second slurry mixture to form a soft composite using a weight ratio of from 10:1 to 1:2.

Abstract: The present invention relates in general to implantable compositions, and method for preparing same, containing a calcium salt-containing component, optionally demineralized bone, a plurality of discrete fibers, optionally a flow additive, and optionally continuous reinforcing fibers or an array of organized fibers in the form of mesh. Advantageously, the discrete fibers have a specific aspect ratio (length/diameter) from about 50:1 to about 1000:1. The addition of a small amount of discrete fibers and/or the continuous reinforcing fibers or fiber mesh can cause drastic increases in certain mechanical properties including flexural strength, flexural toughness, and/or screw pullout strength.

Abstract: The invention relates to a method for stabilising a metastable soluble anhydrite III, to a method for producing a hydraulic binder based thereon, to the thus obtainable hydraulic binder, to a method for the use thereof in the cement industry and to an industrial plant for carrying out the inventive method. The method consists in stabilising a metastable soluble anhydrite III by mechanically stressing the particles thereof in such a way the crystal structure of the particles is modified and the metastable phase thereof is stabilised. Said invention makes it possible to stabilise the metastable soluble anhydrite III particles without using current steps for heating and quenching said particles.

Abstract: The invention is a composition of an architectural papier-mâché, and articles made therewith. Articles formed from using the architectural papier-mâché have excellent weather resistance, and can be used outdoors, as well as indoors. The composition is comprised of cellulose insulation and a joint compound. Cellulose insulation is a paper-based material, like newsprint or phonebook paper that is shredded and chemically treated with boric acid, which imparts resistance to mold, mildew, fungus, insects, moisture and flammable combustion.

Abstract: Disclosed are formulations adapted to form a foamed cementitious composition, the foamed cementitious composition itself, a method of forming a hydraulic binder foam, and a method of conveying and applying the resulting foam to a substrate. A pumpable cementitious slurry is formed, the slurry is mixed with a gas such as air, and is subjected to mechanically created turbulence to generate gas bubbles and create a foam, which preferably is stabilized by a foam stabilizing agent such as polyvinyl alcohol present in the slurry. The foam is then conveyed to a nozzle or other suitable dispense point from which it is applied, for example sprayed, preferably uniformly, onto a substrate to be coated. Prior to dispensing, a set accelerator is preferably injected, which causes the foam to gel, which in turn improves the hangability of the product on a substrate. The spray material adheres to the substrate and hardens to form an insulative coating on the substrate.

Abstract: A composition including two components is provided. When the two components are admixed in the method of the invention a polymer-modified gypsum composition is provided. The admixture exhibits a useful balance of setting time and stability.

Abstract: A novel cement is alkalescent, capable of solidifying a wide range of soil and applicable to biological environment. The cement composition contains 100 parts by weight of magnesium oxide, 5 to 25% by weight of at least one of silicic acid, alumina and iron oxide, 3 to 35 parts by weight of a phosphate, 2 to 30 parts by weight of gypsum and 0.005 to 7 parts by weight of a hydroxycarboxylic acid or a ketocarboxylic acid.

Abstract: Disclosed are formulations adapted to form a foamed cementitious composition, the foamed cementitious composition itself, a method of forming a hydraulic binder foam, and a method of conveying and applying the resulting foam to a substrate. A pumpable cementitious slurry is formed, the slurry is mixed with a gas such as air, and is subjected to mechanically created turbulence to generate gas bubbles and create a foam, which preferably is stabilized by a foam stabilizing agent such as polyvinyl alcohol present in the slurry. The foam is then conveyed to a nozzle or other suitable dispense point from which it is applied, for example sprayed, preferably uniformly, onto a substrate to be coated. Prior to dispensing, a set accelerator is preferably injected, which causes the foam to gel, which in turn improves the hangability of the product on a substrate. The spray material adheres to the substrate and hardens to form an insulative coating on the substrate.

Abstract: A gypsum wallboard that exhibits antimicrobial characteristics is disclosed. A method for making the wallboard is also disclosed. Suitable antimicrobial agents that may be applied to the wallboard or any components thereof include propiconazole, sodium pyrithione, tolyl diiodomethyl sulfone; tebuconazole; thiabendazole; 3-iodo-2-propynyl butylcarbamate; and mixtures thereof.

Abstract: The present invention relates to a method of preparing a hydraulic binder wherein at least the following two binders are mixed together: a) a first hydraulic binder having as one of its main components the mineral compound C4A3{overscore (S)}; and b) a sulfate second binder based on calcium sulfate hemihydrate and/or anhydrite obtained by applying heat treatment to gypsum. The present invention also provides a binder comprising amongst its main components: a) a mineral compound C4A3{overscore (S)}; and b) a compound comprising a hemihydrate of calcium sulfate of &agr; or &bgr; form and of general formula CaSO4, ½H2O and/or an anhydrite of III form of general formula CaSO4, &egr;H2O with &egr; lying in the range 0 to 0.5, preferably in the range 0.06 to 0.11, or an anhydrite of II form of formula CaSO4.

Abstract: A process for synthesizing a hydraulic binder based on natural calcium sulfate (gypsum), the process consisting in heating the calcium sulfate to obtain a large proportion of anhydrite III or &agr; anhydrite, and then in quenching. The process consists in: completely dehydrating the calcium sulfate, and suddently cooling the matter thus dehydrated. The present invention finds a preferred application in the construction industry in obtaining a hydraulic binder that can be used as cement.

Abstract: Coating compositions and methods of their use are described herein for the reduction of corrosion in imbedded metal structures. The coatings are applied as liquids to an external surface of a substrate in which the metal structures are imbedded. The coatings are subsequently allowed to dry. The liquid applied coatings provide galvanic protection to the imbedded metal structures. Continued protection can be maintained with periodic reapplication of the coating compositions, as necessary, to maintain electrical continuity. Because the coatings may be applied using methods similar to standard paints, and because the coatings are applied to external surfaces of the substrates in which the metal structures are imbedded, the corresponding corrosion protection may be easily maintained. The coating compositions are particularly useful in the protection of metal-reinforced concrete.

Abstract: The invention concerns a composition in dry state for mortar or concrete, comprising a cement and an antishrinkage agent. The invention is characterized in that the antishrinkage agent consist of a calcium sulphate, particularly an anhydrous calcium sulphate, associated with at least a glycol ether.

Abstract: A composition comprising calcined gypsum, trimetaphosphate ion, and a water-soluble linear polymer formed by the addition reaction of ethylene oxide and/or alkoxy-substituted ethylene oxide with water, having enhanced strength when set and exhibiting high plasticity and workability such that it readily can be applied to a substrate, is disclosed.

Abstract: Fiberboards are provided containing at least about 65 wt. % calcium sulfate dihydrate derived from hemihydrate or anhydrous gypsum, and at least about 7 wt. % pulped paper fibers. The boards are capable of being formed into structural members having superior mechanical properties and/or fire resistance, including screw-holding capacities in excess of 650 lbs.

Abstract: A method of purifying a flue gas desulfurization aqueous waste slurry containing calcium-sulfur salts and residual solid grits, fly ash, carbon and oils by supplying the aqueous waste slurry to a screening station to remove the grits, passing the grit-free aqueous waste slurry to a magnetic separator to remove fly ash components, and transferring the aqueous slurry to a floatation cell to remove carbon and oils therefrom. A purified aqueous slurry of calcium-sulfur salts is removed from the floatation cell which can be used in producing quality plaster, wallboard, or feedstock in producing &agr;-hemihydrate gypsum.

Abstract: A method for processing a pulverulent calcium sulphate material in order to obtain a hydraulic binder is described, including combining the following two successive processing steps: (a) heating the pulverulent material in a curing tunnel (1) at a temperature of 220-360° C., under conditions suitable for primarily forming an &agr;-type calcium sulphate, and (b) subjecting the heated material to a thermal quenching step in a cooling apparatus (2), with a cold, dry gas to stabilise the &agr; anhydrite and to prevent its conversion into other crystallographic types. The method provides a novel hydraulic binder with an &agr; anhydrite content of more than 35 wt. %, and with improved strength and behavior in fire resistance properties.

Abstract: The invention provides cementitious mixtures, particularly for use as shotcrete binding materials. The resultant shotcrete has characteristics of rapid setting as low as 5 to 10 minutes, high early compressive strength (5 to 25 MPa in two hours curing, 20 to 60 MPa in one day curing), high permanent compressive strength and negligible shrinkage. High aluminous content roasted cement clinkers with gypsum, anhydrite, lime, limestone, bentonite and other additives are used in the mixtures. There are especially suitable for use in shotcrete engineering. The methods of using the improved shotcrete are similar to those of using Portland cement, with significantly decreased rebound at site.

Abstract: The invention relates to a self-levelling fluid mortar including calcium sulphate, granulates, lime, water and either a silica and a compound containing alumina or a pozzuolana, and to a screed obtained from said fluid mortar. It also relates to the combined use of lime and either of a silica and of a compound containing alumina or a pozzuolana to increase the mechanical strength and reduce the water sensitivity of a screed.

Abstract: A Portland cement clinker free of C.sub.4 A.sub.3 S having the following proportions of clinker phases, in % by wt.:--C.sub.3 S: 40 to 80--C.sub.4 AF: <20--C.sub.2 S: <30--C.sub.3 A: <20and a SO.sub.3 content from 1.0 to 3.0% by wt., based on the clinker, obtained by burning a mixture of raw materials containing CaO, SiO.sub.2, Al.sub.2 O.sub.3, Fe.sub.2 O.sub.3 and an additive containing SO.sub.3 at temperatures from 1200.degree. to 1350.degree. C. centigrade, the use thereof and a Portland cement.

Abstract: A method and apparatus for producing SO.sub.2 -containing gas and cement clinker by splitting waste gypsum and anhydrite, using paper fibers as the reducing agent, and firing the splitting residue with additives. The cement forming additives are formed into a mixture with the anhydrite and the mixture is compacted before the final drying and calcining, whereupon the anhydrite containing mixture is subjected to the splitting reaction and firing to form the clinker.

Abstract: A novel binder for interior plasters having a calcium sulphate component capable of binding in the presence of water and a finely divided residual material component comprised primarily of calcium sulphite, where the residual material is a product of flue gas desulphurization of coal-fired combustion plants.

Abstract: This invention relates to a grout composition comprising a Portland cement, a high alumina cement, anhydrous calcium sulphate, an effective amount of a lithium salt and an effective amount of a strong base. According to another aspect of the invention, instead of using a strong base directly in the grout composition, a first compound and a second compound is added to the grout composition which in use react to form an effective amount of a strong base when the grout composition is mixed with water.

Abstract: Both the drying and also the removal of the water crystalization take place carefully in a respective fluidized bed apparatus (A, B) without any danger of overheating. This is achieved by a complete homogenous fluidization through indirectly heated hot gas. A substantial quantity of energy is transferred via heat exchanger systems (4 or 12) in the fluidized layer. These are heated by heat carrying media. The constructional design of the fluidized bed apparatuses (A, B) which have a rectangular base outline ensures a narrow dwelltime spectrum and a pronounced temperature/moisture profile without the aid of differentially fluidized chambers. Because of the comparatively cold infeed zone and the careful heating which thereby arise the characteristics of the crystals are favourably influenced. The product is characterized by high quality homogenity. In the case of the calcining of moist gypsum no undesired gypsum modifications arise.

Abstract: The present invention pertains to a portland cement clinker containing the following amounts of clinker phases, in wt. %:C.sub.3 S: 30 to 80,C.sub.4 A.sub.3 S: 5 to 30,C.sub.4 AF: <30,C.sub.2 S: <40,C.sub.3 A: <20,and an SO.sub.3 content between 2 and 8 wt. %, obtained by calcining a raw material mixture containing CaO, SIO.sub.2, AL.sub.2 O.sub.3, and Fe.sub.2 O.sub.3 in the presence of an additive containing SO.sub.3 and an additive containing fluorine at temperatures between 1,150.degree. C. and 1,350.degree. C.

Abstract: A process, and the product produced thereby, for the preparation of a waste solidification material from hardened fluorogypsum as a by-product of the manufacture of hydrofluoric acid by reacting fluorospar with sulfuric acid, removing hydrogen fluoride from the reaction product, slurrying the by-product with water, placing the slurried by-product fluorogypsum in settlement ponds until the fluorogypsum hardens, the hardened fluorogypsum having a pH of greater than about 5 to about 13, including heating the hardened fluorogypsum to evaporate substantially all water physically mixed with the fluorogypsum and further heating the fluorogypsum to reduce the water chemically bound to calcium sulfate in the fluorogypsum to form about 0.5% to about 9% by weight.

Abstract: A method for treating produced gypsum and, in particular, a method for treating flue-gas desulfurization gypsum forms highly active, modifiable gypsum binders of high strength with simultaneously drying, deagglomerating and dehydrating. Pursuant to the invention, produced gypsum (flue-gas desulfurization gypsum), with a particle size ranging up to 200 .mu.m, to which 10% by weight of milled natural gypsum is optionally added, is dehydrated at a material temperature of 335.degree. to 363.degree. K. and at a pressure ranging from 2.5 to 8 kpa, the dehydration being concluded when anhydrite III constitutes 50% to 100% by weight.

Abstract: A method for incorporating siloxane into a water-resistant, gypsum-based article is disclosed, comprising, (A) adding said siloxane to water; (B) mixing said siloxane/water mixture with calcined gypsum to form an aqueous slurry; and (C) allowing said slurry to set to form a set gypsum-based, water-resistant article.

Abstract: A binder composition is shown for agglomerating ore fines in a heap leaching ore recovery process. The binder composition comprises a calcareous component, a sulfate component and a siliceous-aluminous component such as fly ash. The ore fines are agglomerated by adding the binder composition thereto and a leach bed is formed of the agglomerated ore. The leach bed is leached with a leaching agent to form a leach liquor the metal values are recovered from the leach liquor.

Abstract: A mortar for the production of a floor is prepared from a mixture of anhydrite binder, sand, fluidized bed ash from the fluidized bed firing of a sulfur-bearing fuel such as coal, water and a selection of additives, resulting in advantageous technological properties.

Abstract: A method for forming strong and durable pellets from dust collected from stack gases. The dust includes CaSO.sub.3, CaSO.sub.4 and unreacted CaD. A portion of water required for total hydration with the dust is blended in a mixer. The moistened powder is stored in a conditioning container wherein the moistened powder is chemically reacted and heated to form a hydroxide with the oxides in the powder. Water is added to the hydrates and the wetted hydrates are subjected to an intense second mixing. The wetted hydrates are then pelletized in a pelletizer.

Abstract: A shaped article of gypsum possessing heretofore unattainable high strength, a method for the production of the shaped article, and a method for the production of inclusion water indispensable to the hardening by hydration of the production of the shaped article of gypsum are disclosed.

Abstract: A process, and the product produced thereby, for the preparation of a waste solidification material from hardened fluorogypsum as a by-product of the manufacture of hydrofluoric acid by reacting fluorospar with sulfuric acid, removing hydrogen fluoride from the reaction product, slurrying the by-product with water, placing the slurried by-product fluorogypsum in settlement ponds until the fluorogypsum hardens, the hardened fluorogypsum having a pH of about 3 to about 5, including heating the hardened fluorogypsum to evaporate substantially all water physically mixed with the fluorogypsum and further heating the fluorogypsum to reduce the water chemically bound to calcium sulfate in the fluorogypsum to from about 0.5% to about 9% by weight.