Combustion of copper concentrate particles in a stagnant gas furnace

The oxidation behavior of two copper concentrates, "La Escondida" and "La C aridad" was studied in a stagnant furnace. "La Escondida" concentrate is a high grade copper concentrate based on chalcocite (Cu2S) and pyrite (FeS2), while "La Caridad" contains pyrite (FeS2), chalcopyrite (CuFeS2), chalcoci te (Cu2S) and covellite (CuS). The results show that the ignition behaviour of "La Escondida" is similar to that of La Caridad. Although "La Escondida " does not contain chalcopyrite, both pyrite and chalcocite are present and form chalcopyrite before ignition, leading to oxidation behaviour similar to that of "La Caridad" concentrate. The extent of reaction in both cases w as found to increase with increasing oxygen concentration and temperature. The extent of reaction also increased with increasing particle size due to changes in composition of the particles.