Abstract: A cement clinker is produced by utilizing a combustible waste material as a fuel for preheating or calcining a cement material, by using an apparatus comprising a cement material feeder, a preheater or calcinator, a rotary kiln, cooler and means for flowing an exhaust gas from the rotary kiln to the preheater or calcinator, which apparatus is characterized by a heat-decomposer which is located between the preheater or calcinator and the rotary kiln and in which a combustible material is heat decomposed with an exhaust gas from the rotary kiln and the resultant combustible gas is burnt in the preheater or calcinator.

Abstract: A silicon nitride-cordierite article, and process for fabricating is described. The silicon nitride imparts a high mechanical strength, and the cordierite contributes to a lower thermal conductivity making the composition especially useful for internal parts of a diesel engine. The mechanical strength can be increased by crystallizing the continuous cordierite glassy phase of the article. Crystallization of the continuous cordierite glassy phase is accomplished by the addition of a nucleating agent such as zirconium dioxide in the formulation and a subsequent reheating step after densification.

Abstract: An elemental carbon-containing refractory composition having superior erosion and oxidation resistance due to the addition of prescribed amounts of boron carbide.

Abstract: Disclosed is a method for rapidly forming a solid monolith of an aqueous mixture of an ion exchange resin and boric acid. A fouling agent and sufficient basic accelerator to neutralize the mixture are added. Cement is then added which hardens in a few hours. Also disclosed is a composition of the ion exchange resin, boric acid, water, a fouling agent, a basic accelerator, and cement.

Abstract: A process for manufacturing stabilized elementary particles of lignocellulose material includes, in sequence, the following operations: mechanically reducing with a cutter, crushing with a hammer mill, grading, subjecting to heat treatment by passage in a rotary furnace at a temperature decreasing from 800.degree. C. to 75.degree. C., subjecting to chemical impregnation-absorption-precipitation treatment by successive actions on a hot product and by spraying of a soluble calcium salt and a silicate, drying, and stabilizing. The invention finds use in the fields of construction, agriculture, horticulture, and related fields.

Abstract: Cementing compositions and methods of using such compositions in oil, gas and water well cementing operations to reduce fluid loss from the composition to the formation are disclosed. Such compositions incorporate certain copolymers of N, N dimethylacrylamide and 2-acrylamido, 2-methyl propane sulfonic acid having mole ratios of between 1:4 and 4:1 respectively and average molecular weights of between about 75,000 and about 300,000.

Abstract: A composition for making impermeable walls and other underground structures comprising water, a cement, a silica compound in a dispersed form, and an activating agent selected from the group consisting of an alkaline base and an alkaline salt of a weak acid which do not contain silica, the ratio by weight of lime to silica being less than 1 and preferably between approximately 0.3 to 0.5.

Abstract: A method of treating zeolites to remove therefrom discoloring impurities and improve the brightness thereof, comprising the steps of mixing a pulverized sedimentary zeolite ore with a dispersant and water to form a dispersed aqueous zeolite slurry, degritting the resulting slurry, removing fines containing discoloring impurities from the degritted slurry, thereafter subjecting the zeolite slurry to a fine media milling, removing fines containing discoloring impurities from the resulting fine milled slurry, subjecting the fine milled slurry to magnetic separation to remove magnetic discoloring impurities, bleaching the resulting zeolite slurry and then recovering the zeolite in dry form from the resulting slurry. The dry finely ground zeolite made by this method has a particle size of at least 85% below 2 .mu.m and a Tappi brightness of at least 90.

Abstract: An early high-strength mineral polymer composition is formed of a polysialatesiloxo material obtained by adding a reactant mixture consisting of alumino-silicate oxide (Si.sub.2 O.sub.5,Al.sub.2 O.sub.2) with the aluminum cation in a four-fold coordination, strong alkalis such as sodium hydroxide and/or potassium hydroxide, water, and a sodium/potassium polysilicate solution; and from 15 to 26 parts, by weight, based upon the reactive mixture of the polysialatesiloxo polymer of ground blast furnace slag. Sufficient hardening for demolding is obtained in about 1 hour with this composition.

Abstract: A composition obtained by mixing fly ash, calciumsulphate hemihydrate and oxisludge, a product caught from gases emanating from converters during steel production.Oxisludge containing substantial amounts of iron is used in an amount comprised between 0,2 and 10%, preferably 1 to 5%.The composition is a loose mass or consists of granular products.

Abstract: A method and apparatus for thermally reacting one or more inorganic materials, the method involves the step of maintaining a flame in a combustion chamber at a predetermined reaction temperature by supplying a sufficient quantity of a hydrocarbon fuel and oxygen into the flame through a fluid stream comminuting the inorganic materials to be reacted to a particle size which can be transported by gas flow and suspending the comminuted inorganic compound in an intimate admixture with the fluid stream containing the hydrocarbon fuel and oxygen and passing the admixture to the interior of the flame to effect thermal reaction of the particulate inorganic material. The apparatus can comprise a blower, a grinding means, a furnace means, and a means for collecting the reacted material.

Abstract: A process for improving the fluidity and conveyability properties of moist calcium sulfate precipitates, having a free water content of more than about 5% by weight, which entails mixing quicklime (CaO), burnt dolomite (CaO+MgO) or a mixture thereof, in finely ground form to said moist calcium sulfate precipitate in an amount of about 10% by weight or greater, based upon the calcium sulfate content, to form a homogeneous mixture of the same.The homogenized mixtures so prepared have good pourability and can be conveniently stored or conveyed. They can be used as setting retarders in cement or, they can be used in the production of gypsum wall board and plaster.

Abstract: A method and apparatus for burning fine grained products, such as in the manufacture of cement clinker from raw cement meal wherein preheated, calcined meal is heated in a separate heating assembly to a temperature from approximately 900.degree. C. to approximately 1250.degree. C. and is then sintered into clinker in a burning assembly such as a rotary tubular kiln. The present invention provides a means for achieving a fast and uniform continuous heating in the heating assembly without reaching the critical temperature of melt phase formation and without danger of encrustations, the heat required for rapid heating being released in controlled amounts in the heating assembly, where it is immediately absorbed by the product, the heat being provided by a plurality of points of fuel introduction and/or combustion air introduction distributed over the heating assembly.

Abstract: A process for formulating and applying a silicate/silica cement composition to the treatment of a wellbore comprising the steps of mixing an appropriate silica compound with an aqueous water-soluble silicate solution and injecting the mixture into the wellbore in such a manner as to penetrate void spaces in or adjoining the wellbore. The mixture is cured in place, hardening into a solid impermeable cement which plugs the penetrated void spaces.

Abstract: A refractory composition for use in the manufacture of pipes for casting steel, the composition consisting essentially of: (a) from 96 to 98% by weight of zirconia which is partially stabilized by CaO, MgO or Y.sub.2 O.sub.3, at least 90% of which has a particle size of between 0.1 and 10 .mu.m, and (b) from 2 to 4% by weight of an aluminous hydraulic binder, this composition having the following overall chemical analysis: 1.4 to 3.2% by weight of Al.sub.2 O.sub.3, 3.7 to 4.6% by weight of CaO, or 0.36 to 1.15% by weight of CaO plus 2.7 to 3.5% by weight of MgO, or 0.36 to 1.15% by weight of CaO plus 5.36 to 8.80% of Y.sub.2 O.sub.3, less than 1% by weight of SiO.sub.2 +Na.sub.2 O+Fe.sub.2 O.sub.3 +TiO.sub.2 taken together, and ZrO.sub.2 to make up to 100%.

Abstract: A dry blend capable of forming a fast-setting cement when reacted with an aqueous component. The blend comprises: a solid phosphorus pentoxide (P.sub.2 O.sub.5) containing component; a solid component comprising a magnesium containing compound; and an optional aggregate.The solid P.sub.2 O.sub.5 containing component is preferably spent solid phosphoric acid catalyst.The dry blend remains a free flowing powder until contacted with the aqueous component, preferably water, then a reaction occurs forming a fast-setting cement.

Abstract: High alumina slide gate compositions comprising aluminous grain, carbonaceous material, high purity alumina, silicon metal and resin.

Abstract: A castable silica refractory consisting essentially of 58-78 by weight percent amorphous silica selected from the group consisting of vitreous and fused silica or a combination thereof; 10-30 by weight percent quartzite; 4-10 by weight percent volatilized silica; 2-3 by weight percent wollastonite powder; and 1-3 by weight percent white portland cement; plus as additions about 0.4 by weight percent water reducing agent and 6-10 by weight percent water.

Abstract: A cementitious composite material exhibiting an exceptional combination of high tensile, flexural and compressive strengths as compared with generally accepted values for Class H cements is produced from a mixture having a low pH and containing a tobermorite-like gel.

Abstract: A method and apparatus for burning cement clinker from differing mineral base materials. One of the base materials has a relatively high proportion of components which form melt phases at a predetermined temperature and another base material has a relatively slight proportion of such components. The two base materials are separately thermally pretreated. The base material higher in melt phases is at least partially melted after thermal pretreatment and is introduced into a clinker reactor in its molten state together with the thermally pretreated base material which is lower in melt phases and still exists in the solid phase. The mixture is heat treated and finish-burned into clinker in the clinker reactor. The invention also comprehends apparatus for performing the method of the invention.