METHOD FOR RECOVERING CALCIUM-CONTAINING SOLID COMPONENT FROM STEELMAKING SLAG AND RECOVERED SOLID COMPONENT

• Main Authors: YAMAMOTO, Masaya, ASABA, Akihiro, FUKUI, Yasushi, MATSUO, Shoichi
• Format: Patent
• Language: English; French; German
• Published: 31.01.2018
• Subjects: ARTIFICIAL STONE; CEMENTS; CERAMICS; CHEMISTRY; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDINGMATERIALS; COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM,CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THERARE-EARTH METALS; CONCRETE; INORGANIC CHEMISTRY; LIME, MAGNESIA; METALLURGY; METALLURGY OF IRON; PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OFWROUGHT-IRON OR STEEL; REFRACTORIES; SLAG; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS; TREATMENT OF NATURAL STONE

The purpose of the present invention is to provide a method for recovering calcium-containing solid components from steelmaking slag, with which it is possible to easily increase the calcium recovery rate. With the method, steelmaking slag is immersed in an aqueous solution containing carbon dioxide, and calcium in the steelmaking slag is made to leach out into the aqueous solution. Next, the immersed steelmaking slag is removed from the aqueous solution, and, subsequently, the pH of the aqueous solution is increased. When solid components precipitated by doing so are recovered, it is possible to recover solid components containing 20 % or more by mass in terms of calcium atoms.