PROCESS OF TREATING SULFIDE ORES CONTAINING GOLD AND/OR SILVER AND AS ACCOMPANYING METAL AT LEAST IRON

摘要

The ore which contains gold and/or silver and as accompanying metal at least iron is calcined at temperatures in the range from 500 to 900.degree.C with the addition of oxygen-containing gas. There is obtained a metal-oxide-containing solids mixture and a SO2-containing exhaust gas. The solids mixture from the calcination is cooled, the temperature being reduced by at least 50.degree.C. The cooled solids mixture is added to a fluidized-bed reactor, and SO2-containing exhaust gas is introduced into the fluidized-bed reactor. In the reactor, metal sulfate is produced in the solids mixture, so that at least 10 % of the sulfur content are bound in the exhaust gas. Solids mixture containing metal sulfate is withdrawn from the fluidized-bed reactor, is stirred up with an aqueous acid solution, thereby dissolving metal sulfate. The remaining solids are supplied to a recovery of gold and/or silver.