Method for roasting refractory gold ores

摘要

Refractory gold ores are roasted by means of oxygen-containing gases in a circulating fluidised bed at temperatures from 500 to 750 DEG C. The temperature in the lower part of the fluidised bed in the reactor is adjusted to be 4 to 30 DEG C higher than in the upper part of the fluidised bed, and the fluidising gas is introduced into the reactor at a velocity of from 30 to 200 m/sec.