Abstract: In a method of effectively utilizing dusts incurring in the reduction of iron ore by means of a reducing gas and separated on that occasion in a scrubber in the form of sludges, the sludges at first are dehydrated and are used as starting materials for the production of cement (FIG. 1).

Abstract: To produce molten pig iron by melt-reduction of iron ores of various grain sizes containing a fraction A including grain sizes to which diameters of less than 0.2 mm correspond, by pre-reducing the ore by reducing gas, completely reducing the pre-reduced material and smelting it to molten pig iron in a melter gasifier, the pre-reduced ore fraction A is separated from a fraction B including larger grain-size particles by classification by means of reducing-gas and the two fractions A and B are completely reduced separately and fed to the melting zone of the melter gasifier.