Blast furnace slag is usually treated by three methods: rapid cooling, slow cooling and semi-rapid cooling, and three properties are obtained. Different blast furnace slag: water-quenched slag (granulated slag), lump slag (heavy slag) and expanded slag (expanded beads).
(1) water quenching slag: the slag is rapidly cooled by water, compressed air or steam, usually by water cooling. In the quenching process, most of the components in the slag can't crystallize and remain glassy, so the water-quenched slag of blast furnace has good activity.
(2) Slag (heavy slag): Due to slow cooling, most chemical components have crystallized and most of them are inactive.
(3) Expanded slag (expanded beads): it is the product of semi-quenching treatment of blast furnace slag. The massive or granular expansion slag usually formed by the mechanical interaction with water is mainly composed of glass body (95%), and its appearance is mostly spherical, which is not only active, but also light in weight.