A method for precipitating metal waste is characterized in that the waste which contains one or more dissolved metal salts, is mixed with a boron compound, and the pH is adjusted to a value at which precipitation takes place in the presence of precipitation nuclei necessary for the formation of metal borates.

A method for precipitating metal waste is characterized in that the waste which contains one or more dissolved metal salts, is mixed with a boron compound, and the pH is adjusted to a value at which precipitation takes place in the presence of precipitation nuclei necessary for the formation of metal borates.

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.

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 is provided for recovering mercury from a crude oil into an alkaline ammonium sulfide contacting solution. Soluble mercury complexes in the contacting solution are converted to particulate mercury. The particulate mercury can be recovered by filtering, and the ammonium sulfide in the contacting solution recycled to the aqueous contacting solution.

Disclosed are a method for preparing a non-sintered shell-wrapped ceramsite using solid waste meanwhile immobilizing a heavy metal in river sediment, and a non-sintered river-sediment-based shell-wrapped ceramsite, which relate to the technical field of building materials. The disclosure combines river sediment with a solid waste powder and an alkali activating powder material, and adopts multiple-step granulations to realize particle size control and physical pore formation, thereby obtaining a non-sintered ceramsite. A sulfoaluminate cement and a Portland cement are used to encapsulate the non-sintered ceramsite and form a shell by wrapping, thereby preparing a non-sintered river-sediment-based shell-wrapped ceramsite with internal porosity and dense shell.

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.

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.

Disclosed are a method for preparing a non-sintered shell-wrapped ceramsite using solid waste meanwhile immobilizing a heavy metal in river sediment, and a non-sintered river-sediment-based shell-wrapped ceramsite, which relate to the technical field of building materials. The disclosure combines river sediment with a solid waste powder and an alkali activating powder material, and adopts multiple-step granulations to realize particle size control and physical pore formation, thereby obtaining a non-sintered ceramsite. A sulfoaluminate cement and a Portland cement are used to encapsulate the non-sintered ceramsite and form a shell by wrapping, thereby preparing a non-sintered river-sediment-based shell-wrapped ceramsite with internal porosity and dense shell.

Disclosed are a method for preparing a non-sintered shell-wrapped ceramsite using solid waste meanwhile immobilizing a heavy metal in river sediment, and a non-sintered river-sediment-based shell-wrapped ceramsite, which relate to the technical field of building materials. The disclosure combines river sediment with a solid waste powder and an alkali activating powder material, and adopts multiple-step granulations to realize particle size control and physical pore formation, thereby obtaining a non-sintered ceramsite. A sulfoaluminate cement and a Portland cement are used to encapsulate the non-sintered ceramsite and form a shell by wrapping, thereby preparing a non-sintered river-sediment-based shell-wrapped ceramsite with internal porosity and dense shell.