GB544394A - Improvements in or relating to the treatment of ores - Google Patents

Abstract

544,394. Extracting metals. WATSON, F. (American Ore Reduction Corporation). June 30, 1941, No. 8197. [Class 82 (i)] [Also in Group III] Ores, such as antimony sulphide ores, containing a constituent capable of being converted into an oxide fume, are roasted to form such a fume which is then passed, before substantial condensation thereof, through a reducing zone to form the metal. In the plant shown, preheated ore from a hopper 10 and pre-heated air from a chamber 13 are passed through a heated roasting chamber 15, non-volatile matter being separated in a chamber 20 and the oxide fume being passed through a pipe 23 where it is mixed with heated air from a pipe 26 and powdered coal from a hopper 25. The mixture is reduced in a chamber 24, metal being collected in a chamber 30 and the remaining stream passing between baffles 31 where any entrained metal may be collected and returned to the chamber 30. The residual gases are withdrawn through a pipe 33, are burnt in a furnance 16 which surrounds the roasting chamber 15, and effect also the heating of the chambers 13, 20. In treating antimony sulphide ores the roasting temperature may be controlled to produce antimony trioxide and not tetroxide. If arsenic is present along with antimony, both the oxides formed may be reduced to metal, and the arsenic either condensed separately or burnt with the other gases in the furnace 16.