Bottom blown oxygen cupel

In 1986 Britannia Refined Metals (Northfleet, U.K.) introduced technology for the treatment of Parkes cmst, a triple alloy of Ag, Zn, Pb, which by 1992 had been adopted by seven lead refineries (22). The technology consists of a three-stage process in which the silver-rich cmst is first Hquated to reduce its lead content, then placed in a sealed furnace where the 2inc is removed by vacuum distillation and, finally, the silver—lead metal is treated in a bottom blown oxygen cupel (BBOC) to produce a Htharge slag and dorn metal. 

Fig. 15. Bottom blown oxygen cupel (BBOC) in positions for (a) blowing oxygen and (b) tapping slag.

Brittania A process for removing silver from lead, operated by Brittania Refined Metals in England, using ore from the Mount Isa mine in Australia. After initial concentration by the Parkes process, and removal of the zinc by vacuum distillation, the mixture, which contains silver (70 percent), lead, and some copper is treated in a bottom blown oxygen cupel in which lead and copper are removed by the injection of oxygen through a shielded lance. 

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