Method for eluting calcium from steel-making slag, method for collecting calcium from steel-making slag, and device for eluting calcium from steel-making slag

The purpose of the present invention is to provide a method for eluting calcium from a steel-making slag, with which a larger amount of calcium can be easily eluted from the steel-making slag to an aqueous solution comprising carbon dioxide. To this end, the present invention relates to a method for eluting calcium from a steel-making slag. In the present invention, stirring of a slurry comprising a steel-making slag is suppressed in a region within a pulverizing/settling tank on the top side near a liquid surface to cause the steel-making slag to settle, while at the same time the steel-making slag included in the slurry is pulverized or the surface of the steel-making slag is crushed in a region within the pulverizing/settling tank on the bottom side. Carbon dioxide is introduced into the slurry, and the pulverized or crushed steel-making slag is contacted with an aqueous solution in which the carbon dioxide is dissolved.