Abstract: A limestone calcined clay cement construction composition comprises a) a cementitious binder comprising one or more calcium silicate mineral phases and one or more calcium aluminate mineral phases, and having a Blaine surface area of at least 3800 cm2/g; b) a supplementary cementitious material having a Dv90 of less than 200 ?m comprising (b-1) a calcined clay material and (b-2) a carbonate rock powder in a weight ratio of (b-1) to (b-2) in the range of 0.5 to 2; c) optionally, an extraneous aluminate source; d) a sulfate source; and e) a polyol. The composition contains a controlled amount of available aluminate, calculated as Al(OH)4?, from the calcium aluminate mineral phases plus the optional extraneous aluminate source; and the molar ratio of total available aluminate to sulfate is 0.4 to 2.0. The construction composition further comprises f) an ettringite formation controller.

Abstract: A cement slurry in a downhole well has a composition that includes a cement in an amount of 60% to 80% by weight of the cement slurry, water in an amount of 20% to 40% by weight of the cement slurry, and a retarder in an amount of 0.1% to 2% by weight of the cement slurry. The cement includes 70% to 90% of at least one silicate by weight of the cement. The retarder includes sodium lignosulfonate with an alkali content of no more than 5.0 g Na2O equivalent/liter of admixture.

Abstract: Disclosed is a method and system for blending a foam modifier with foaming agent online, e.g., as may be particularly useful for gypsum or cement slurries. The foam modifier comprises a fatty alcohol that is added to a gypsum or cement slurry that includes foaming agent, such as an alkyl sulfate surfactant. The fatty alcohol can be a C6-C16 fatty alcohol in some embodiments. The use of such a foam modifier can be used, for example, to stabilize the foam, reduce waste of foaming agent, improve void size control in the final product, and improve the gypsum board manufacturing process.

Abstract: A heat exchanger and a gas-fired furnace including the same are provided. The heat exchanger includes at least two heat exchange shell enclosures; and at least three rows of heat exchange tubes arranged along a furnace air flow path. Each of the heat exchange tubes defines a leaving-tube-end and an entering-tube-end, two adjacent rows are spaced from each other, the at least three rows of heat exchange tubes are connected in a leaving-tube-end to entering-tube-end fashion sequentially via the at least two heat exchange shell enclosures to define a substantially serpentine flue gas passage.

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: A process for reducing the set time a plaster slurry. The process comprises the steps of, providing a pre-determined amount of water, providing a pre-determined amount of the plaster, mixing the water and the plaster together at a first time to form a slurry, and, re-directing a portion of the slurry formed at the first time to combine with slurry formed at a second time.

Abstract: An apparatus for calcining gypsum including a housing having a bottom wall, open top, and a plurality of side walls extending therebetween. A fixture is located adjacent the open top for receiving gypsum from a source and transferring the gypsum into the housing. At least one burner is connected to the housing and operable for combusting an air-fuel mixture to heat the gypsum. At least one serpentine burner conduit extends from the burner through the housing and terminates through a support floor of the apparatus. The exhaust flow is then directed through a fluidization pad and into the gypsum to further heat the gypsum product. An agitation mechanism is operable to mix the gypsum adjacent the fluidization pad to prevent pockets of gypsum from coagulating and preventing fluidization of the gypsum.

Abstract: Clinkered materials containing high concentrations of {(C,K,N,M)4(A,F,Mn,P,T,S)3(cl,{overscore (S)})} (crystal X), and {(C2S)3(C{overscore (S)})3 Ca(f,cl) 2} or {(C2S)3(C{overscore (S)})3Ca(f,cl)2} (crystal Y), and/or {C5S2{overscore (S)}) (crystal Z) directly from the kiln, rapidly hardening ultra-high early strength cement including these clinkered materials, methods for forming and using said compositions and the cements so produced are claimed. The methods include the steps of forming a mixture of raw material containing CaO, MgO, Al2O3, Fe2O3, TiO2, Mn2O3, SiO2, SO3, Na2O, K2O, P2O5 and F, respectively designated C, M, A, F, T, Mn, S, {overscore (S)}, N, K, P and f, and heating said mixture to an elevated temperature between 900° C. and 1,200° C.; before determining average amount of crystals X, Y, and Z.

Abstract: Clinkered materials containing high concentrations of {(C,K,N,M)4 (A,F,Mn,P,T,S)3 Cl,{overscore (S)})}(crystal X), and {C2S)3(C{overscore (S)})3Ca(f,Cl)2} or C9S3{overscore (S)}3Ca(f,cl)2 crystal Y), and/or {C5S2{overscore (S)}) (crystal Z) directly from the kiln, rapidly hardening ultra-high early strength cement including these clinkered materials, methods for forming and using said compositions and the cements so produced are claimed. The methods include the steps of forming a mixture of raw material containing CaO, MgO, Al2O3, Fe2O3, TiO2, Mn2O5, SiO2, SO3, Na2O, K2O, P2O5 and F, respectively designated C, M, A, F, T, Mn, S, {overscore (S)}, N, K, P and f, and heating said mixture to an elevated temperature between 900° C. and 1,200° C.; before determining average amount of crystals X, Y, and Z.

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: Cement clinker, characterized in that it comprises Al2O3 and Fe2O3 wherein the mass ratio of Al2O3/Fe2O3 is 0.05-0.62, and alkali components and C2S wherein the content Y (mass %) of alkali components and the content X (mass %) of C2S satisfy the formula: 0.0025X+0.1≦Y≦0.01X+0.8. The production of the clinker allows the incorporation of alkali components into cement with an advantageous effect of enhancement of the hydration of belite and also with suppression of the lowering of flowability, which leads to the reuse of wastes containing alkali components as a cement raw material.

Abstract: The invention concerns a hydration modifying agent for mortar and concrete comprising a combination of 30 to 80% of calcium sulphate, 3 to 60% of ethylene/propylene oxide copolymer and 0.5 to 6% of an activator for the copolymer. The invention also concerns a Portland dry cement comprising 2 to 10 wt. % of said hydration modifying agent and a method for preparing such a mortar or concrete composition, and a self-spreading concrete topping made from said mortar or concrete composition.

Abstract: Clinkered materials containing high concentrations of {(C,K,N,M)4 (A,F,Mn,P,T,S)3 Cl,{overscore (S)})}(crystal X), and {C2S)3 (C{overscore (S)})3Ca(f,Cl)2} or C9S3{overscore (S)}3Ca(f,cl)2 (crystal Y), and/or {C5S2{overscore (S)}) (crystal Z) directly from the kiln, rapidly hardening ultra-high early strength cement including these clinkered materials, methods for forming and using said compositions and the cements so produced are claimed. The methods include the steps of forming a mixture of raw material containing CaO, MgO, Al2O3, Fe2O3, TiO2, Mn2O5, SiO2, SO3, Na2O, K2O, P2O5 and F, respectively designated C, M, A, F, T, Mn, S, {overscore (S)}, N, K, P and f, and heating said mixture to an elevated temperature between 900° C. and 1,200° C.; before determining average amount of crystals X, Y, and Z.

Abstract: A chemical agent for improving the engineering properties of soil includes a mixture of cementitious pozzalans (5 to 60% by mass), calcium sulphate (20 to 80% by mass), an oxide of calcium (15 to 50% by mass) and silica oxide (1 to 30% by weight). Monofilament fibers can also be included in the mix.

Abstract: A composition for use in construction materials, which may be substituted for high performance concrete, patching materials, joint compounds, and the like, such as backer boards or panels, which includes a settable calcium sulfate, preferably a hemihydrate, Portland cement, a finely divided pozzolanic material, lime, and an aggregate, optionally including other additives. The volume ratio of the aggregate to the combined calcium sulfate, Portland cement, pozzolanic material, and lime (a cementitious binder) is equal to or greater than 2/1. Panels made from this composition are useful, particularly when exposed to water since they have good dimensional stability.

Abstract: The present invention is of a cementitious composition containing OPC, calcined gypsum, a source of amorphous silica and a source of amorphous alumina. The ratio of calcium sulfate hemihydrate to OPC is 0.7:1.0 to 1.4:1.0, the ratio of amorphous silica and amorphous alumina to OPC is 0.26:1.0 to 0.4:1.0, and the ratio of amorphous alumina to amorphous silica is 0.3:1.0 to 1.5:1.0. The cementitious composition, by itself and mixed with aggregates, is fast-setting and exhibits good early compressive strength and very high compressive strength after hydration. Despite the high content of calcium sulfate relative to prior art OPC formulations, the cementitious composition according to the present invention is essentially waterproof and exhibits excellent strength characteristics, even after 2 years under water. The use of calcined gypsum in place of alumina cement or even OPC is of great economic advantage, and in addition, provides the cementitious composition with quick-setting characteristics.

Abstract: Clinkered materials containing high concentrations of {(C,K,N,M).sub.4 (A,F,Mn,P,T,S).sub.3 Cl,S)}(crystal X), and {C.sub.2 S).sub.3 (CS).sub.3 C(f,Cl)} or C.sub.10 S.sub.3 S.sub.3 (f,cl) (crystal Y), and/or {C.sub.5 S.sub.2 S) (crystal Z) directly from the kiln, rapidly hardening ultra-high early strength cement including these clinkered materials, methods for forming and using said compositions and the cements so produced are claimed. The methods include the steps of forming a mixture of raw material containing CaO, MgO, Al.sub.2 O.sub.3, Fe.sub.2 O.sub.3, TiO.sub.2, Mn.sub.2 O.sub.5, SiO.sub.2, SO.sub.3, Na.sub.2 O, K.sub.2 O, P.sub.2 O.sub.5 and F, respectively designated C, M, A, F, T, Mn, S, S, N, K, P and f, and heating said mixture to an elevated temperature between 900.degree. C. and 1,200.degree. C.; before determining average amount of crystals X, Y, and Z.

Abstract: A composition comprises anhydrous alumino-silicate, diatomaceous earth, and/or other natural pozzolans, white clinker, and white gypsum interground together and in a ratio by weight of 5-20% anhydrous alumino-silicate, diatomaceous earth, and/or other natural pozzolans, 3-7% gypsum, and 73-92% white clinker.

Abstract: A composition suitable for adding to water to produce a water-resistant hydraulic solid which composition comprises components (a), (b) and (c) as follows:(a) calcium sulphate hemihydrate;(b) portland cement;(c) calcined clay having a pozzolanic activity;wherein the percentages by weight of components (a), (b) and (c) in the said composition are in the respective ranges:(a) from 20% to 98%;(b) from 1% to 50%;(c) from 1% to 30%;the percentages of components (a), (b) and (c) adding to 100% in the three component composition.

Abstract: Foamed cement slurry compositions and a process or method for cementing well casings or pipes utilizing such compositions are described, the compositions being characterized by critical ratios of particular solid and liquid components. The slurry compositions formed provide unique properties such as rapid set or hydration, and are designed particularly for use with weakly consolidated formations.

Abstract: Novel cementitious systems comprised of gypsum, calcined clay, and clinker consisting essentially of hydraulic calcium silicates are disclosed which have the following properties: (1) a water demand of less than about 33% nc; (2) one-day strengths of at least about 1000 psi; and (3) low alkali functionality. By increasing the amount of calcined clay, the resulting cementitious system will sequentially gain the following properties: (1) alkali non-reactiveness; (2) alkali resistance; and (3) low chloride permeability. Novel methods of preparing the novel cementitious systems of this invention are also disclosed. The novel methods not only reduce production costs by decreasing fuel and raw material consumption, but they also allow the cement producer to proactively address significant environmental concerns related to the manufacturing process.

Abstract: The hardenable mortar composition consists of a bonding agent component including a hydraulic bonding agent, such as cement, gypsum or mortar, and a paste-forming agent consisting of a liquid solvent inert with respect to the hydraulic bonding agent, and an aqueous component kept separate from the bonding agent component until the two components are mixed to form a hardened mortar composition. The aqueous component includes water and a hydrophobic adsorbent or absorbent. The hydrophobic adsorbent or absorbent is included in the aqueous component to avoid the emergence of the paste-forming agent, which is at the very least unsightly, when the aqueous component is mixed with the bonding agent component. The hydrophobic adsorbent or absorbent binds the paste-forming agent which would otherwise escape during mixing and remains as an inert additive in the setting mortar composition, without reducing the hardness thereof.

Abstract: Novel cementitious systems comprised of gypsum, calcined clay, and clinker consisting essentially of hydraulic calcium silicates are disclosed which have the following properties: (1) a water demand of less than about 33% nc; (2) one-day strengths of at least about 1000 psi; and (3) low alkali functionality. By increasing the amount of calcined clay, the resulting cementitious system will sequentially gain the following properties: (1) alkali non-reactiveness; (2) alkali resistance; and (3) low chloride permeability. Novel methods of preparing the novel cementitious systems of this invention are also disclosed. The novel methods not only reduce production costs by decreasing fuel and raw material consumption, but they also allow the cement producer to proactively address significant environmental concerns related to the manufacturing process.

Abstract: There is disclosed a softy mud solidifying agent which comprises cement, and at least two members selected from the group consisting of pozzolanic substances, inorganic compounds and organic compounds. The solidifying agent is capable of solidifying dredged earth, sand, softy mud, etc. in such a manner that their mixture can be re-cast into water to form submerged banks, artificial fish-gathering places, etc., without causing water pollution.

Abstract: Methods for forming very early setting, ultra high strength cements and the cements so produced are claimed. The methods comprise forming a mixture of raw materials containing SiO.sub.2, Al.sub.2 O.sub.3, CaO, Fe.sub.2 O.sub.3, and SO.sub.3, respectively designated S, A, C, F, and S such that the overall molar ratio of A/F exceeds approximately 0.64 and the overall molar ratio of S/A+F is between approximately 0.35 and 0.25. This mixture is heated to n elevated temperature between 1,000.degree. C. and 1,200.degree. C. for a sufficient period of time to produce a clinker containing high concentrations of C.sub.4 A.sub.3 S. The average amount of C.sub.4 A.sub.3 S is then determined and a final mixture is formed utilizing the high C.sub.4 A.sub.3 S clinker, C containing hydraulic or portland type cement and soluble CS anhydride to produce a final cement mixture having a C.sub.4 A.sub.