Provided is a practically valuable and economically excellent insolubilizing material for a specific toxic substance: that is useful for insolubilizing treatment for a heavy metal or the like conducted by applying the insolubilizing material for a specific toxic substance to soil or on the surface of the soil; that is capable of effectively insolubilizing and immobilizing the heavy metal or the like; that is capable of making treated matter neutral so as to be reusable and environment-friendly; and moreover that is capable of imparting strength to the treated matter as necessary; and with which the heavy metal or the like is not re-eluted even when the treated matter is exposed to an environment under a neutral condition or an acidic condition. An insolubilizing material for a specific toxic substance to be used so that soil does not reach a strongly alkaline region of a pH of 11 or more, wherein the insolubilizing material for a specific toxic substance comprises an amorphous aluminum compound or a derivative thereof as a main component, or an insolubilizing material for a specific toxic substance to be used so that soil containing a heavy metal or the like does not reach a strongly alkaline region of a pH of 11 or more, the insolubilizing material for a specific toxic substance functioning also as a solidifying material, wherein the insolubilizing material for a specific toxic substance comprises gypsum obtained by adding and mixing, to the gypsum, the amorphous aluminum compound and the derivative thereof in a range of 0.5 to 60 mass parts relative to 100 mass parts of the gypsum, and a method for improving soil using the insolubilizing material for a specific toxic substance.

A method and composition for stabilizing drill cuttings commences by providing precipitated calcium carbonate (PCC). The PCC is dried to a moisture level of about 10% or less. Drying by heat not to exceed 400 F. is preferred to prevent changes in the PCC. The dried PCC is blended with kiln dust to compose a generally uniform admixture. In the admixture, the kiln dust is not to exceed 40%. The admixture is introduced to the drill cuttings to initiate a nucleation reaction within the commixture of drill cuttings and the admixture.

This invention relates to a solidifying agent for solidifying radioactive waste, and more particularly to a solidifying-agent composition for solidifying radioactive waste, including alumina cement and a gypsum powder. The solidifying-agent composition including alumina cement and a gypsum powder is capable of effectively minimizing an increase in the volume of a solidified radioactive waste product to a level satisfying physical and chemical safety regulations upon the solidification of radioactive waste.

A method for processing a radioactive liquid waste containing boron of the present invention includes: a molar ratio control step of adding an alkali metal or an alkali metal compound to a radioactive liquid waste containing boron to control an alkali metal/boron molar ratio in the radioactive liquid waste to be 0.8 or more; a drying step of drying the radioactive liquid waste having the controlled molar-ratio using a dryer to form a powdered waste; a dissolving step of mixing the powdered waste with kneading water to prepare a solution; and a kneading step of adding a hydraulic inorganic solidifying material to the solution, and kneading the hydraulic inorganic solidifying material and the solution for solidification.

Provided is an inorganic solid waste-microbial composite curing agent and its preparation method and application. The inorganic solid waste-microbial composite curing agent consists of the following raw materials in parts by weight: steel slag, active magnesium oxide, recycled powder, stearic acid, borax, carbonic anhydrase bacteria, Bacillus subtilis, and soluble calcium salts. The preparation method includes performing granulation on steel slag, active magnesium oxide, recycled powder, stearic acid, borax, etc. into porous materials through dry rolling extrusion and compression, and loading carbonic anhydrase bacteria and Bacillus subtilis into the porous materials. By adding inorganic solid waste-microbial composite curing agent into the sludge and introducing CO.sub.2, the sludge is quickly solidified through the carbonization and microbial mineralization of inorganic solid waste. At the same time, microorganisms can effectively decompose organic pollutants in the sludge, achieving the goal of harmless, stabilized and resourceful utilization of sludge.

Provided is an inorganic solid waste-microbial composite curing agent and its preparation method and application. The inorganic solid waste-microbial composite curing agent consists of the following raw materials in parts by weight: steel slag, active magnesium oxide, recycled powder, stearic acid, borax, carbonic anhydrase bacteria, Bacillus subtilis, and soluble calcium salts. The preparation method includes performing granulation on steel slag, active magnesium oxide, recycled powder, stearic acid, borax, etc. into porous materials through dry rolling extrusion and compression, and loading carbonic anhydrase bacteria and Bacillus subtilis into the porous materials. By adding inorganic solid waste-microbial composite curing agent into the sludge and introducing CO.sub.2, the sludge is quickly solidified through the carbonization and microbial mineralization of inorganic solid waste. At the same time, microorganisms can effectively decompose organic pollutants in the sludge, achieving the goal of harmless, stabilized and resourceful utilization of sludge.

A method for processing a radioactive liquid waste containing boron of the present invention includes: a molar ratio control step of adding an alkali metal or an alkali metal compound to a radioactive liquid waste containing boron to control an alkali metal/boron molar ratio in the radioactive liquid waste to be 0.8 or more; a drying step of drying the radioactive liquid waste having the controlled molar-ratio using a dryer to form a powdered waste; a dissolving step of mixing the powdered waste with kneading water to prepare a solution; and a kneading step of adding a hydraulic inorganic solidifying material to the solution, and kneading the hydraulic inorganic solidifying material and the solution for solidification.

Methods for increasing the stability of a slag using a source of silica and a source of boron ions, and compositions for use in said methods.

Systems and methods of the present invention include a method for the treatment of drilling wastes and coal combustion residues, comprising combining at least a first drilling waste with coal combustion residues to form a paste, combining at least a second drilling waste with coal combustion residues to form a compactable fill, and placing the paste and the compactable fill in a landfill. Other embodiments include a method of treating drilling wastes and coal combustion residues, comprising combining at least one drilling waste with a coal combustion residue to form a paste. Further embodiments include containing the paste within at least one geotextile container. Still further embodiments include placing the geotextile container in a landfill.

The present invention relates to a process for the manufacture of a grout for concrete comprising a stage of mixing a hydraulic binder and water, characterized in that the process comprises a stage of deep freezing the water in the solid form.