The invention relates to a process for extracting metals and salts from titanium-bearing minerals such as perovskite. More particularly, although not exclusively, the invention relates to extracting titanium dioxide and optionally other compounds from melter slag derived from an iron-making process.

The invention relates to a process for extracting metals and salts from titanium-bearing minerals such as perovskite. More particularly, although not exclusively, the invention relates to extracting titanium dioxide and optionally other compounds from melter slag derived from an iron-making process.

The invention relates to a process for extracting metals and salts from titanium-bearing minerals such as perovskite. More particularly, although not exclusively, the invention relates to extracting titanium dioxide and optionally other compounds from melter slag derived from an iron-making process.

The present invention provides an apparatus and a method for producing magnesium sulfate through flue gas desulfurization, and specifically provides an apparatus and a method suitable for producing magnesium sulfate through direct crystallization in a magnesium oxide based desulfurization waste liquid tower of flue gas with a small content of oxygen like a coal fired boiler flue gas. The apparatus includes an oxygenation equipment, a flue gas desulfurization equipment, a seriflux cycling equipment, an evaporation and concentration equipment, a cycling and precipitating equipment, an oxidation equipment, a crystallization equipment, a centrifugation equipment and a drying equipment, etc. The apparatus and method of the present invention can greatly reduce electric power consumption of oxidation fans and steam consumption, as well as guarantee desulfurization efficiency and quality of a magnesium sulfate by-product, reduce lots of operation costs of the magnesium sulfate production system, and reduce desulfurization operation costs.

The present invention provides an apparatus and a method for producing magnesium sulfate through flue gas desulfurization, and specifically provides an apparatus and a method suitable for producing magnesium sulfate through direct crystallization in a magnesium oxide based desulfurization waste liquid tower of flue gas with a small content of oxygen like a coal fired boiler flue gas. The apparatus includes an oxygenation equipment, a flue gas desulfurization equipment, a seriflux cycling equipment, an evaporation and concentration equipment, a cycling and precipitating equipment, an oxidation equipment, a crystallization equipment, a centrifugation equipment and a drying equipment, etc. The apparatus and method of the present invention can greatly reduce electric power consumption of oxidation fans and steam consumption, as well as guarantee desulfurization efficiency and quality of a magnesium sulfate by-product, reduce lots of operation costs of the magnesium sulfate production system, and reduce desulfurization operation costs.

Describes a method of producing a magnesium sulfate and hydrous ammonia double salt or Boussingaultite ((NH.sub.4).sub.2SO.sub.4.MgSO.sub.4.6H.sub.2O), using as a source of magnesium a liquid effluent rich in magnesium sulfate originally from hydrometallurgical processes for the production of metals such as nickel, copper, rare earths. According to the invention, the process route for the production of Boussingaultite with physical properties suitable for use in fertilizer mixtures involves the steps of precipitating the Boussingaultite double salt, filtration and thermal drying.

Describes a method of producing a magnesium sulfate and hydrous ammonia double salt or Boussingaultite ((NH.sub.4).sub.2SO.sub.4.MgSO.sub.4.6H.sub.2O), using as a source of magnesium a liquid effluent rich in magnesium sulfate originally from hydrometallurgical processes for the production of metals such as nickel, copper, rare earths. According to the invention, the process route for the production of Boussingaultite with physical properties suitable for use in fertilizer mixtures involves the steps of precipitating the Boussingaultite double salt, filtration and thermal drying.

The present application pertains to processes for making calcium oxide and/or sulfuric acid from calcium sulfate. In some embodiments the processes comprise reacting a component comprising calcium sulfate with a second component comprising magnesium sulfite under conditions to form a solid comprising calcium sulfite and a solution comprising magnesium sulfate. Next, at least a portion of the solid comprising calcium sulfite is decomposed to form a second solid comprising calcium oxide, or calcium hydroxide, or cement, or clinker, or any combination thereof.

The present application pertains to processes for making calcium oxide and/or sulfuric acid from calcium sulfate. In some embodiments the processes comprise reacting a component comprising calcium sulfate with a second component comprising magnesium sulfite under conditions to form a solid comprising calcium sulfite and a solution comprising magnesium sulfate. Next, at least a portion of the solid comprising calcium sulfite is decomposed to form a second solid comprising calcium oxide, or calcium hydroxide, or cement, or clinker, or any combination thereof.

This invention relates to safe immobilization and disposal of arsenic found in industrial waste streams and residues in the form of clean and compact well grown scorodite solids.