Roasting Copper extraction

the roasting process undertaken in combination reverberatory furnaces. in roaster, copper concentrate partially oxidised produce calcine , sulfur dioxide gas. stoichiometry of reaction occurs is:

2 cufes2 + 3 o2 → 2 feo + 2 cus + 2 so2

roasting leaves more sulfur in calcined product (15% in case of roaster @ mount isa mines) sinter plant leaves in sintered product (about 7% in case of electrolytic refining , smelting smelter).

as of 2005, roasting no longer common in copper concentrate treatment, because combination reverberatory furnaces not energy efficient , so2 concentration in roaster offgas dilute cost-effective capture. direct smelting favored, e.g. using following smelting technologies: flash smelting, isasmelt, noranda, mitsubishi or el teniente furnaces.