Abstract: The present invention discloses a method for preparing the inorganic hardenable slurry and the use of same in the solidification of wastes. In addition to water, the essential parts of the slurry are inorganic components including borates, cement-base powder and other additives such as magnesium oxide, gypsum and silica. The slurry is low in viscosity before solidification and flows freely,and within approximately 30 minutes after preparation the slurry becomes hardened into a highly solidified substance. The solidification of the slurry is resulted mainly from reaction of borates and the cement-base powder and to obtain a best result the weight of borates must be the same as that of the cement-base powder or even higher than the weight of the latter. The solidification mechanism differs entirely from the simple hydration reaction that brings about solidification of cement.The present invention also teaches a method for solidifying wastes with this hardenable slurry, i.e.

Abstract: An admixture for cement compositions containing tetrahydroborate, and cement composition containing a tetrahydroborate admixture made of salt borohydride, cement, aggregate and water. Since tetrahydroborate has the expansion effect hardly influenced by temperature, expansion amount is easily controlled. Since cells generated by foaming are fine, a hardened body with the excellent resistance to freezing and thawing can be obtained.

Abstract: N-phosphonomethyl iminodiacetic acid may be used as an additive to retard the setting time of Portland cement.

Abstract: The storage and processing times of sprayed concrete can be significantly extended by the addition of a retarder, a chemical compound which is capable of chelating with calcium ions. Preferred retarders are phosphonic acid derivatives which have at least one amino and/or hydroxyl group. The retarder can be used for both wet- and dry-sprayed concrete, the usual accelerators can be used for activation, and the strength is not adversely affected.

Abstract: New additive composition, in liquid or powder form, for thin slabs, plasters, concretes, prefabricated elements and refrectory elements, with insulating and impermeabilizing properties and with antishrink characteristics, comprising a bonding agent and an additive comprising a mixture of carbonates containing 59-75% CaCO.sub.3, 25-37% Si(CO.sub.3).sub.2, 0-2% Al.sub.2 (CO.sub.3).sub.3, 0-1% MgCO.sub.3 and 0-1% Fe.sub.2 (CO.sub.3).sub.3.

Abstract: A process is disclosed for producing a hydraulic cement binder for both general and special applications, consisting of water, cementitious materials, boric acid, borax, citric acid, an alkali metal activator, and with or without ground silica. This cement making process with sequences for mixing the composition, is particularly useful because it provides: time to mix all components adequately, unrestricted transporting time that can be terminated, at will, followed by alterable placement and finishing times. The process provides the means for creating a hydraulic cement binder that can be used as a neat cement or it can be extended with fillers, such as sand and gravel, to make mortar or concrete, that rapidly gains very high structural strengths.

Abstract: A blended, hydraulic cement binder, is disclosed, consisting of water, fly ash, Type III portland cement, Type I portland cement, slag cement, ground silica, boric acid, borax, citric acid and an alkali metal activator. The cement binder and sequences for mixing the composition, is particularly useful because it provides: time to mix all components adequately, unrestricted transporting time that can be terminated, at will, followed by alterable placement and finishing times. The cement binder can be used as a neat cement or it can be extended with fillers, such as sand and gravel, to make mortar or concrete, that rapidly gains very high structural strengths.

Abstract: Set retarded cement compositions for cementing across a zone or zones in a well having enhanced compressive strength and rapid gel strength development after placement. The cement compositions are comprised of hydraulic cement, sufficient fresh water to form a pumpable slurry, a set retarder comprising a copolymer of 2-acrylamido, 2-methylpropane sulfonic acid and acrylic acid having a average molecular weight below about 5000 and any other desired additives. Methods of cementing utilizing the cement composition also are provided.

Abstract: Portland cement concrete-carbon fiber structure displays high tensile and flexural strengths, low electrical resistivity and high electromagnetic interference shielding effectiveness. The structure comprises cement concrete having a small predetermined proportion of carbon fibers dispersed therein. During the fabrication of the structure, there is added thereto an accelerating admixture comprising polyethanolamine and one of metal sulfate plus metal aluminum sulfate or metal nitrite plus metal chloride. The accelerating admixture comprises a small predetermined weight percentage of the cement in the structure. Additional improvements are obtained by using a small proportion of water-reducing agents.

Abstract: A carbon fiber-reinforced cementitious composite having high strength, which comprises continuous carbon fibers and a cured cement composition, comprising cement particles having an average particle size up to about the average diameter of the carbon fibers, the cured cement composition being substantially interposed between the individual carbon fibers; and a method for producing it.

Abstract: A low resistance non-permeable backfill especially for use in vertical anode beds for the cathodic protection of subsurface metallic structures includes a mixture of portland cement, calcined fluid petroleum coke, micro-size carbon rods and high structure carbon black mixed with water and pumped as a high density fluidized suspension into the anode bed, particularly around the casing of a deep anode bed of the general type described in U.S. Pat. No. 3,725,699 to Tatum.

Abstract: The present invention relates to a composition for cementing, containing a small amount of NaCl and from 35 to 150 l/t of sodium silicate. A cement-salt bond having good characteristics such as rheology, fluid loss, etc. . . . is obtained.

Abstract: An electrical ground system as a metal conductor surrounded by a composition comprising a mixture of portland cement, sized calcined fluid petroleum coke, micro-carbon rods and carbon black.

Abstract: A cementing composition for forming a low density cement slurry comprising a hydraulic cement and shot coke.

Abstract: A method and composition for solidification or semicolidification of single or multi-phased waste including mixing the waste with a composition including having as its major component a cement, and, as lesser components, a fixative, an absorbant, and optionally an emulsifier. The composition of the invention is mixed with the waste and dried.