Hoesch HUttenwerke AG, Dortmund, West Germany, is an integrated steel work of the Estel-group. The nominal annual production capacity-is about 7 Mio tons of steel. Hoesch has a long experience in operation of diffe- rent types of slag granulation plants and of utilization of the granulated product. This experience is used to granulate a large amount of blast furnace slag and to process it in own cement plants and produce blast fur- nace cement.