Method and device for granulating molten material

A method for granulating molten material comprising a slag having, as its main constituents, CaO:

• >30% by weight, SiO2:
• >30% by weight, and Al2O3:
• >6% by weight, in particular blast furnace slag, the method comprising introducing the molten material into a granulating chamber, wherein the granulating chamber includes water as a cooling liquid, quenching and granulating the molten material to obtain latent hydraulical particles, adding an acid to the water, wherein the water is in a water bath or the granulating chamber includes a sump and the molten material is introduced into either the water bath brought to boiling temperature or introduced above the water in the sump brought to boiling temperature, and subjecting the molten material in the granulating chamber to a mechanical disintegration by means of a disintegrator.