Depending on slag cooling different type of slag is produced.
1) Air cooled slag
2) Granulated slag
3) Foamy slag
The air cooled slag produced, after tapping the slag cooled in air. This type of slags are usually very hard lump crystalline form. And subsequently these are crushed and sieved.
Applications:
construction aggregate applications, manufacture of mineral wool, cement and glass, and a soil conditioner.

The Granulated slag produced by rapid quenching by water jet ( such that it avoid the crystallisation). This type of slags are usually has non crystalline powder form. This type of slag has good cementitious property. So, This is mainly used for cement making.

The Foamy slag produced by quenching by controlled mannar such that foam will form in tha slag. The cooling rate is not too high and not too low. It has cellular structure. This type of slag mainly used for tiles, bricks, building blocks.

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