Abstract: The invention relates to a method and a system for producing cement clinker from raw cement mixture, wherein one part of the raw cement mixture is preheated in a calciner preheater, and the other part of the raw cement mixture is preheated in an oven preheater, the preheated raw cement mixture is pre-calcined in a calciner which is operated according to the oxyfuel method, the pre-calcined raw cement mixture is fired in an oven, the fired raw cement mixture is cooled in a cooler, the calciner preheater is operated using exhaust gases of the calciner, the oven preheater is operated using exhaust gases of the oven, an entrained flow reactor is used as the calciner, a part of the calciner exhaust gas being recirculated to the calciner after being used in the calciner preheater, and the oven exhaust gas undergoes a post-combustion CO2 separation.

Abstract: An inerting process for impurities in aggregates intended for preparation of hydraulic or hydrocarbon compositions, includes adding to the composition or to one of its constituents a cationic polymer corresponding to at least one derivative of a natural polymer or a polymer of natural origin selected from the group including dextrin (in particular yellow dextrin and white dextrin), chitosan, chitin, alginates, hemicellulose, pectin, polyols or proteins.

Abstract: A building product comprises calcium sulphate dihydrate particles bound by an organic binder. The calcium sulphate dihydrate particles each have a longest dimension and a lateral dimension, wherein the lateral dimension corresponds to the maximum breadth of the particle about the axis defined by the longest dimension. The calcium sulphate dihydrate particles have a low aspect ratio such that for at least 75% of the calcium sulphate dihydrate particles, the value of the lateral dimension is at least 20% of the value of the longest dimension.

Abstract: A calcium phosphate cement composition that includes the following two components: A) one or several calcium phosphate powders suspended in an aqueous solution including inhibitor cations inhibiting a reaction of the calcium phosphate powders with water, the inhibitor cations being selected from Mg2+, Sr2+ and Ba2+ at a concentration greater than 0.01 M; and B) an aqueous solution including Ca2+ cations at a concentration greater than 0.1 M. This calcium phosphate cement compositions can be safely stored for years yet still retain its full reactivity when mixed.

Abstract: Provided herein is a cementitious composition comprising a photoactivator, wherein the photoactivator is capable of converting NOx to NO2— or NO3— when exposed to ultraviolet (U.V.) or visible light.

Abstract: Disclosed are cementitious product, as well as cementitious slurry, and method of forming the product. To reduce density in the cementitious product, foam is included in the slurry and in the method of forming the product. The slurry includes cementitious particles, water, and air bubbles such as from compressed air. Instead of using detergent chemistry at the gas/water interface of bubbles, the present invention uses a surface modifying agent for the cementitious particles in the slurry. The modified particles act to produce stable foam in the slurry. As an example mode of introduction, the surface modifier can be added (e.g., as solid or solution) directly into a bulk cementitious slurry that forms the product. As another example, the surface modifier can be added in a separate solution with water, air bubbles, and cementitious particles that serve as additive to the main cementitious slurry, where the separate solution is then added to the main cementitious slurry.

Abstract: A composite cement material is prepared from cement material and carbon nanotubes, wherein the carbon nanotubes are present from about 0.02 wt % to about 0.10 wt % based on weight of cement material. The process for preparing such cement compositions includes sonicating a mixture of a surfactant, water, and carbon nanotubes; and blending the dispersion and the cement material to form a cementitious paste. The process may also include curing the cementitious paste. The composite cement materials are useful in a variety of cement applications where a reduction in nanoscale flaws and fractures is desired.

Abstract: A composition and process for the manufacture thereof for use in a hybrid building material comprising at least in part Syngenite (K2Ca(SO4)2.H2O) and Struvite-K (KMgPO4.6H2O). Specified constituents, including magnesium oxide (MgO), monopotassium phosphate (MKP) and stucco (calcium sulfate hemihydrate) are mixed in predetermined ratios and the reaction proceeds through multiple phases reactions which at times are proceeding simultaneously and in parallel and reaction may even compete with each other for reagents if the Struvite-K reaction is not buffered to slow down the reaction rate). A number of variable factors, such as water temperature, pH mixing times and rates, have been found to affect resultant reaction products. Preferred ratios of chemical constituents and manufacturing parameters, including predetermined and specified ratios of Struvite-K and Syngenite may be provided for specified purposes, optimized in respect of stoichiometry to reduce the combined heat of formation to non-destructive levels.

Abstract: A composition, in the form of a concrete, cement paste, mortar or intermediate thereof, comprising one or more cementitious binder materials present in an amount ranging from 0.5% to 75% by weight of the composition, attapulgite present in an amount ranging from 0.01% to 1.00% by weight of the composition, and optionally water. Although subject to many uses, in some embodiments, the composition is suitable for applications in need or desire of self-consolidating concretes (SCCs), precast concrete, shotcrete, and the like. Although makeable by multiple methods, in some embodiments, the composition is made by mixing the component ingredients. In some embodiments, the composition has one or more properties chosen from superior aggregate suspension, eliminated segregation, improved workability, improved flowability, improved pumpability—or improved overall performance—of concretes.

Abstract: A process is disclosed which converts intractable, semi-solid drill cuttings into a free-flowing granular, soil-like SDC material, which, after appropriate compaction, can be beneficially used for a variety of engineering construction applications, thereby removing the need for disposal with its associated costs and environmental impact, and as a result improving the overall economics for gas well development, together with improving corporate sustainability and reducing liability.

Abstract: Disclosed is a process for calcining active blending material involving feeding material outside of a kiln head and the blending material obtained. The process comprises feeding material from outside of kiln head of rotary kiln into inside of kiln hood and to grate cooler, wherein the material is coal gangue, shale, clay, peat, mud and the like which can form active cement component through low temperature calcining, and calcining the material at low temperature. Disclosed also is a cement production apparatus for carrying out the process provided, comprising feeder nose(s) provided on the kiln hood and/or grate cooler for feeding the material.

Abstract: Pozzolanic cement compositions and method manufacturing the same are described. These cement compositions may include a pozzolanic material and an activator based on a salt of glycolic acid, glyceric acid, malic acid, tartaric acid, malonic acid, glutaric acid, maleic acid, formic acid, acetic acid, propionic acid, or butyric acid, a retarder based on hepto-gluconates, sulfate salts, sugars, sugar acids, lignins, and/or an accelerator based on amines. The cement compositions may have less than 10% by weight Portland cement. The pozzolanic cement compositions including these activators, accelerators, and retarders can have improved properties such as longer setting time, better slump retention, and improved strength.

Abstract: A calcium sulfoaluminate-based concrete with a permeability of less than 1000 Coulombs. Rapid-setting low chloride-ion permeability calcium sulfoaluminate (CSA) cements and concretes include CSA and a suitable polymer such as a sol-gel derived, organic-inorganic, silica based hybrid coating solutions of polystyrene-butylacrylate polymers containing active silanol groups protected by hydroxyl groups containing polyalcohol, or other polymers. Such polymers may be added as powders or as liquid in the finish mill. Other rapid-setting low chloride-ion permeability (CSA) cements and concretes include CSA with selected particle size distributions, and do not require use of any polymer. These CSA cements and concretes have low chloride-ion permeability, high early strength, fast setting times, low-shrinkage, and high freeze-thaw resistance.

Abstract: Disclosed herein are fiber reinforced cement composite materials incorporating a 3-mode fiber blend that includes cellulose pulp and synthetic fibers in a ratio selected to provide the composite material with improved water absorption characteristics and the same or improved mechanical properties as compared to equivalent composite materials reinforced with predominantly or all cellulose fibers. Also disclosed herein are fiber blends comprised of a combination of cellulose fibers and polypropylene fibers adapted to reinforce cementitious composite articles manufactured by the Hatschek process and autoclave cured.

Abstract: The invention provides compositions and methods directed to carbonation of a cement mix during mixing. The carbonation may be controlled by one or more feedback mechanisms to adjust carbon dioxide delivery based on one or more characteristics of the mix or other aspects of the mixing operation.

Abstract: Cementitious compositions and methods for preparing and using the cementitious compositions to yield hardened concrete. The cementitious compositions yield hardened concrete having reduced or attenuated water vapor emission and lower internal relative humidity (IRH). Cementitious compositions are characterized by the property of rapid surface drying while maintaining good workability, particularly when using porous lightweight aggregates that absorb substantial amounts of water. Methods of decreasing water availability and increasing surface drying of concrete, including lightweight concrete, are provided. A water soluble ionic salt may be used to sequester water within the pores and capillaries of the cement paste and/or porous lightweight aggregate by modifying the colligative property of pore water.

Abstract: Embodiments provided herein relate to removing liquid from soil or other moisture rich media. In some embodiments, a method for solidifying sludge is provided and involves providing a sludge, fluidizing the sludge to form a fluidized sludge, adding a gelling agent to the fluidized sludge in an amount sufficient to form a slurry, and adding a dewatering agent to the slurry in an amount sufficient to dewater the slurry, thereby solidifying the sludge.

Abstract: A method is disclosed. The method includes providing a cementitious material, the cementitious material including an absorbing material. The method also includes absorbing a fluid into the absorbing material during hydration of the cementitious material. The method further includes retaining the fluid in the absorbing material after hydration of the cementitious material.

Abstract: A low density annular grout composition for filling voids. The composition may consist of cementitious fly ash, water, set retarder and cellular foam. The composition may have a compressive strength of between 100 and 600 psi at seven days and less than 1500 psi at 28 days. The composition may have a density between 20 and 75 pcf. Also disclosed is a method of filling a void with a low density annular grout composition. The method can include determining the time necessary to fill the void, adding water and set retarder to a cementitious fly ash to make a wet mixture, adding air to the wet mixture, and adding the composition to the void.

Abstract: Coal is combusted in the presence of a clay additive and a slag additive to produce a combustion product that is useful as a pozzolanic additive for cement. The combustion process may be performed in a coal-fired boiler of an electrical power generation plant, resulting in improved operational efficiency and controlled emissions.