Improvements in or relating to the production of metals from their ores

摘要

582,777. Reduction of ores. DUFFIELD, F. L. June 16, 1944, No. 11527. [Class 82 (i)] A method of reduction of metallic ores to their metals by charging such ores accompanied by the appropriate reducing agent into a chamber, capable of rotation and being rendered airtight, containing a segregated mass of refractory material which has previously been heated to a temperature at which such refractory mass contains sufficient superheat to provide for the reduction of the ore. In Fig. 1 a charging chamber A, a reducing chamber B, and a condenser D are joined together and are rotatable about a common horizontal axis. The charging chamber delivers a charge of ore and reducing agent, preferably in the form of a briquetted mixture, gradually to the reducing chamber which contains a segregated mass of refractory material, previously heated to provide the stored-up heat required for reduction. In the reducing chamber the briquetted charge is granulated by the crushing effect of the refractory mass during rotation, causing thin layers of ore and reducing agent to be presented to the hot surfaces of the refractory material. The contents of the charging chamber, reducing chamber and condenser may be subjected to a subnormal pressure. On completion of the reduction, the contents of the reduction chamber are discharged through an opening G on to a screen H where fines and reduction residues are separated from the refractory mass, the latter being hoisted by a skip K to the furnace C in which it is re-heated before being returned to the reduction chamber for the next cycle of operation. While special reference is made to the reduction and distillation of magnesium from an ore containing magnesium oxide or forming magnesium oxide at high temperature the apparatus, by elimination of the condenser, may be made suitable for the reduction of metals which do not sublime or vaporize at the operating temperature.