Abstract: A method of cement clinker manufacture comprises feeding a clinker feed material containing a source of calcium carbonate into a feed end of a cement kiln, the feed material is heat processed in the kiln to produce cement clinker with emission of carbon dioxide from thermal decomposition of said source of calcium carbonate and discharge of the carbon dioxide from the kiln, and cement clinker is discharged from a discharge end of the kiln; a coal ash derived from burning pulverized lignite or sub-bituminous coal is included in the feed material fed into the feed end to replace a portion of the source of calcium carbonate, and provides a source of calcium as well as other components notably silicon and aluminum, in the formation of the cement clinker, with a lowering of the emission of carbon dioxide in the kiln, per unit weight of cement clinker produced.

Abstract: A method of cement clinker manufacture comprises feeding a clinker feed material containing a source of calcium carbonate into a feed end of a cement kiln, the feed material is heat processed in the kiln to produce cement clinker with emission of carbon dioxide from thermal decomposition of said source of calcium carbonate and discharge of the carbon dioxide from the kiln, and cement clinker is discharged from a discharge end of the kiln; a coal ash derived from burning pulverized lignite or sub-bituminous coal is included in the feed material fed into the feed end to replace a portion of the source of calcium carbonate, and provides a source of calcium as well as other components notably silicon and aluminium, in the formation of the cement clinker, with a lowering of the emission of carbon dioxide in the kiln, per unit weight of cement clinker produced.

Abstract: A supplemental agent for a hazardous waste composition containing electric arc furnace dust (EAFD) includes potassium magnesium sulfate or a magnesium salt such as magnesium sulfate or magnesium chloride. The supplemental agent when mixed with EAFD and water, along with either lime inherent within the EAFD or added lime, reduces the leaching of heavy metals from the waste composition over a wide range of leaching conditions, including both acidic, neutral, and alkaline environments. The method for reducing the concentration of heavy metals in a leachate from the EAFD involves forming a mixture of EAFD, water, the supplemental agent, and, optionally, ferrous sulfate, along with lime, then permitting the mixture to react.

Abstract: A decorative aggregate-containing cementitious slurry having decorative aggregate and cementitious matrix composition forms a monolithic structure when effectively applied to a freshly poured cementitious base and simultaneously cured therewith. The slurry and the base are cured for a time sufficient for producing the monolithic structure with a decorative aggregate-containing cementitious surface. The slurry produces a decorative aggregate-containing cementitious layer having a cured thickness effective for permanently securing the decorative aggregate therein with a portion of the decorative aggregate exposed. Various decorative surfaces are produced without requiring expensive hand broadcasting of the decorative aggregate, and without expensive surface grinding. Dry components of the slurry are decorative aggregate and decorative cementitious matrix blend.

Abstract: The present invention discloses a process for producing both steam power and the fast-burnt cement clinker/fast burnt modified coal ash simultaneously in one apparatus, the fast-burnt cement clinker/fast-burnt modified coal ash prepared by said process as well as cement products prepared using them as active substance. It also discloses the apparatus suitable for embodying this process. Said process of the present invention possesses the technoligical features of fast-burning and fast-cooling and contributes a good hydraulic cementitious activity to the said fast-burnt cement clinker/fast-burnt modified coal ash which are capable of being directly used as active substance in cement production of high quality.

Abstract: Cementitious compositions and methods for making the compositions wherein the compositions include high volume of mineral admixtures such as fly ash and blast-furnace slag in combination with rice hull ash. In one embodiment, the cementitious composition is a blend of hydraulic cement, rice hull ash and a mineral addition selected from fly ash and blast-furnace slag. The cementitious compositions can advantageously have high early and 28-day compressive strength and a very low permeability rating.

Abstract: Undried blast furnace slag, for example, granulated blast furnace slag having a water content of 3 to 20, generally 5 to 15%, by weight, is introduced to hot clinker in a cooler downstream of a cement kiln; the water is volatilized or evaporated in the cooler to provide a cement clinker having an effective content of dried blast furnace slag free of water; this permits use of blast furnace slag in a blended cement without the need for separate special steps for drying the slag.

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: Contaminated coal ash, for example flyash contaminated with carbon is introduced to hot clinker in a cooler downstream of a cement kiln; the carbon is combusted in the cooler to provide a cement clinker having an effective content of flyash free of carbon; this permits use of flyash contaminated with carbon without the need for separate special steps for carbon removal; volatile contaminants or contaminants having a volatile component, for example adsorbed ammonia are similarly removed in the cooler by volatilization.

Abstract: Cement and elemental sulfur are produced by forming a moist mixture of a flue gas desulfurization process waste product containing 80-95 percent by weight calcium sulfate hemihydrate and 5-20 percent by weight calcium sulfate hemihydrate, aluminum, iron, silica and carbon, agglomerating the moist mixture while drying the same to form a feedstock, and calcining the dry agglomerated feedstock in a rotary kiln. Sulfur dioxide produced during the calcination is cooled and contacted with hydrogen and carbon monoxide to reduce the same to elemental sulfur.

Abstract: Cement is produced by forming a moist mixture of a flue gas desulfurization process waste product containing 80-95 percent by weight calcium sulfite hemihydrate and 5-20 percent by weight calcium sulfate hemihydrate, aluminum, iron, silica and carbon, agglomerating the moist mixture while drying the same to form a feedstock, and calcining the dry agglomerated feedstock in a rotary kiln. Sulfur dioxide released from the calcium sulfite hemihydrate and calcium sulfate hemihydrate during calcination may be used to produce sulfuric acid, while heat recovered in the process is used to dry the agglomerating feedstock.

Abstract: Methods for combining Class C fly ash into cementitious mixtures for producing concretes that are resistant to sulfate-containing environments. In one method, Class C fly ash is intergound with portland cement clinker and gypsum to produce a cementitions mixture, which, when combined with water and an aggregate produces a hardened concrete that is resistant to sulfate environments. Alternatively, portland cement clinker and gypsum are first interground and the resultant mixture is admixed with Class C fly ash to produce a cementitious mixture. Thie cementitious mixture, in combination with water and an aggregage, produces a hardened concrete that has improved resistance to sulfate environments. In other aspects, a concrete that is stable in sulfate environments is produced by admixing portland cement, Class C fly ash and water containing a source of ions selected from the group consisting of sulfate and hydroxyl anions.

Abstract: With the present invention, a feed preparation system for producing cement includes mixing raw materials with a source of potassium. The mixture is conveyed to feed preparation system where it is placed in condition for treatment in a fluidized bed reactor for thermal processing to produce cement clinker. The potassium combines with the SO.sub.2 generated in the process to form potassium sulfate solids that are filtered from the process gas stream before emission to the atmosphere to thereby reduce sulfur emissions from the fluid bed cement process. The starting material may include white cement raw meal, grey cement raw meal and cement kiln dusts.

Abstract: A concrete mortar is formed by mixing together sand, cement, water and a sewage sludge ash. A foam is added to the mortar to form a foamed concrete composition.

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: Compositions particularly suitable for use in preparation of concrete and mortar products comprising at least one cement and from about 5% to about 30% by weight of the cement of siliceous ash from crop residue, wherein the ash is from about 60% to about 95% by weight silica, at least about 90% of the silica is amorphous, at least about 75% of ash particles are in a size range of from about 4 to about 75 micrometers, and the ash particles have a mean particle diameter measured by laser-light scattering of at least 6 micrometers and a B.E.T. surface area of at least 20 m.sup.2 /g. The cement employed is a portland cement or a blended portland cement. Concrete and mortar products prepared from these compositions are characterized by exhibiting after 28 days a compressive strength of at least 2500 psi and chloride permeabilities of less than 2000 coulombs when measured in accordance with AASHTO T-277.

Abstract: In general purpose concrete compositions, from about 10% but less than about 25% by wt of the usual amount of portland cement for such compositions is replaced with Class F fly ash and cement kiln dust, both abundant and inexpensive waste products, in the weight ratio of such fly ash to cement kiln dust of about 3:1-1:1 with a minimum of about 5% of the replaced portland cement being cement kiln dust. General purpose concrete prepared from these mix compositions exhibit early strength characteristics, especially from day 1 to day 3, generally equal to or better than those exhibited by comparable all portland cement mix compositions.

Abstract: Improved cementitious compositions having increased flexural, tensile and shear-bond strength, increased wear resistance, decreased water permeability and enhanced workability than previous cement compositions, which are prepared with water treated with an emulsified tar component, and preferably a residual amount of sodium tripolyphosphate, are provided. Methods of forming shaped articles therefrom are also provided.

Abstract: A composition, suitable for use as a base in the construction of roads, parking lots, and other areas, is formulated from an ash aggregate comprising municipal solid waste incinerator ash, MSWIA, mixed with an aggregate material; upon addition of cement, compaction and curing, a volumetrically stable solid is formed. The incinerator ash is combined with an aggregate material, crushed, and sifted to remove particles having a size greater than three eights (3/8") inch prior to the addition of cement. The moisture content of the ash aggregate mixture and ash aggregate/cement mixtures are carefully adjusted to achieve maximum compressive strength. When ash aggregates containing less than 50 percent MSWIA are combined with at least 5 percent cement by dry weight, volumetrically stable solids are formed within seven days that have compressive strengths in excess of 300 psi.

Abstract: Improved cementitious compositions having increased flexural, tensile and shear-bond strength, increased wear resistance, decreased water permeability and enhanced workability than previous cement compositions, which are prepared with water treated with an emulsified tar component, and preferably a residual amount of sodium tripolyphosphate, are provided. Methods of forming shaped articles therefrom are also provided.

Abstract: Disclosed is a highly reactive hydraulic binder for the preparation of building, construction and raw materials which contains burned oil shale and at least one compound, selected from the group, consisting ofan amorphous oxide of 3- and/or 4-valent cations,an amorphous hydroxide of 3- and/or 4-valent cations, andan aluminate of 1- and/or 2-valent cations, as well asat least one water reducing agent.

Abstract: A composition for forming a waterproof, high strength, hard material having good insulation properties, comprising a mixture of crushed pumice, type S mortar and glass fibers, which forms the hard material upon the addition of water and after allowing the mixture to cure. The material has superior insulation properties to conventional compositions formed using portland cement instead of type S mortar.