Abstract: The present invention generally relates to a method for hydraulically backfilling empty mined salt cavities. The method comprises combining at least one pozzolanically active waste material with an effective amount of an alkaline earth metal in the form of an alkaline earth metal hydroxide or alkaline earth metal oxide and saturated brine to form a pozzolanic mixture, wherein the relative proportions of said pozzolanically active waste material, alkaline earth metal hydroxide or alkaline earth metal oxide and saturated brine are sufficient for reaction under atmospheric conditions in said salt cavity to form a stable, low porosity, load bearing pozzolanic cement; and hydraulically depositing said pozzolanic mixture in the empty salt cavity.
Abstract: A method and a mixture for chemically stabilizing electric arc furnace dust (EAFD) by entrapping the metals inherent in EAFD within a cementitiously hardened product from the mixture. The method includes using the pozzolanic characteristics of EAFD and forming a mixture of EAFD with sufficient water and lime, as necessary, and then allowing the mixture to react to form a cementitiously hardened product. The hardened product has acceptable leachate concentrations, permeability characteristics and unconfined compressive strength.
Abstract: A method is disclosed for detoxification of aluminum spent potliner by thermal treatment in a rotary kiln while blended with limestone and metal silicates to destroy cyanides and convert the soluble fluoride salts to relatively insoluble calcium fluoride and fluoride-bearing minerals, quenching the hot kiln discharge with an aqueous lime slurry to convert residual soluble fluoride salts on the particle surfaces to an insoluble form, and treating aqueous landfill runoff and capture with lime or limestone and recycling the treated water to the process. The treated material is suitable for landfilling in a non-hazardous waste landfill or marketing as a raw material. Air emissions are innocuous and there is no aqueous discharge.
Type:
Grant
Filed:
October 11, 1991
Date of Patent:
November 17, 1992
Assignee:
Reynolds Metals Company
Inventors:
Donald B. Banker, Dennis G. Brooks, Euel R. Cutshall, Douglas D. Macauley, Dennis F. Strahan
Abstract: Blocks, weighing about 35 lbs., formed of a homogeneous mixture of about 75% gypsum and 25% lime, are strategically placed in surface water that is being damaged by acid rain, where, by timed release of lime, the pH of the water is maintained at about 6.5 pH.
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: An improved method of making a building material comprising activating slag with an activator of Portland cement, an acidic component and a basic component. The acidic component is a phosphate or a mixture of phosphates in an amount of 2 to 40% by weight based on the amount of the slag and activator, which serve as binding agents. The phosphate or mixture of phosphates have surface tension reducing action or a detergent or mixture of detergents is added to the binding agents in an amount of 0.1 to 2% by weight of the binding agents. The basic component is present in an amount of 2 to 20% by weight based on the amount of the binding agents. The basic component is magnesium oxide, or magnesium oxide in combination with earth metal oxides selected from the group consisting of calcium oxide, aluminum oxide, titanium oxide, zirconium oxide, and zinc oxide, with the amount of calcium oxide not exceeding 3% by weight based on the slag.
Abstract: A liquid aqueous sludge is transferred into a cylindrical-conical tank and gitated by blowing in air through a downwardly extending tube. A closed circulation of sludge is established between this main tank and a reagent tank by means of a recycling pump. The reagent tank overflows into the main tank. Chalk is added to the reagent tank and a pozzolanic material is added to the main tank. When the mixture of dilute sludge, chalk and possolanic material is homogeneous, it is transferred to a filter press by means of a further pump. The filter cake is collected for final storage or discharged to set slowly.
Type:
Grant
Filed:
February 23, 1990
Date of Patent:
August 27, 1991
Assignee:
Agence Nationale pour la Recuperation et l'Elimination des Dechets
Abstract: A method and composition are provided for creating smooth surfaces on building structures, particularly concrete structures. A first constituent is prepared by mixing together quantities of acrylic mortar admix, concrete plaster adhesive, joint compound, hydrated lime and water. The first constituent is mixed with Portland cement at the construction site. The resultant mixture is smoothed onto concrete or wooden surfaces of a building structure, and dries in about an hour to produce a smooth, hard surface.
Abstract: A method of producing cement or concrete, comprising the step of adding fly ash to the cement or concrete at the production stage, the fly ash containing lime and reaction products from the reaction occurring between lime and sulphur oxides in connection with the desulphuration of flue gases. To avoid the disadvantageous effects of calcium sulphite and entringite reactions and to increase the used amount of fly ash containing desulphuration waste, the calcium sulphite is oxidized by hydrogen peroxide either before the production of cement or concrete or during the production.
Type:
Grant
Filed:
February 28, 1990
Date of Patent:
January 15, 1991
Assignee:
Oy Iampella AB
Inventors:
Heikki Ahonen, Timo Kenakkala, Pertti Kokkonen
Abstract: The advantae of high alumina cement (early strength, resistance to sulphate attack) are preserved and its disadvantage (weakens with age) is solved by mixing it 50:50 with ground granulated blast furnace slag. This encourages formation of gehlenite octahydrate in preference to or to the exclusion of the harmful `conversion` (weakening) reaction.
Type:
Grant
Filed:
September 28, 1988
Date of Patent:
October 9, 1990
Assignee:
National Reserach Development Corporation