Process for continuously to passive, a metal particles and particles of iron in sponge heated.The product compatado metallic iron passivation and device for continuously to passive heated material of metal particles on in

摘要

1504088 Making passivated iron particles MIDREX CORP 19 May 1976 [5 June 1975] 20757/76 Heading B3A [Also in Division C7] Metal particles (sponge Fe) are passivated by rolling the hot particles into a strip and then simultaneously shearing the strip and densifying the newly cut surfaces. N 2 is preferably fed into the powder feed hopper supplying the powder to the rolls, sponge Fe being heated above 600‹ C. (700-800‹ C.) and roll compacted to 4À5 g./c.c. The strip is preferably slit longitudinally and then sheared between rotary blades and an anvil with sufficient energy to surface melt the cut edges and form a passivated skin. The passivated particles are then cooled by water quenching.