Question

Which furnace is used for roasting?

Answer 1

1. Roasting is the process of heating a Sulphide mineral to a high temperature in the presence of air.
2. The heating of ore lower than its melting point is accompanied by roasting.
3. Roasting involves the solid-gas thermal reaction that includes, oxidation, reduction, sulphonation, chlorination, etc.
4. Roasting Sulphide ore can create major air pollution, and release toxic gases, that cause many environmental issues.
5. Example of roasting of Zinc Sulphide:
   $$\begin{gathered} 2\mathrm{ZnS}\left(\mathrm{s}\right)+3{\mathrm{O}}_2\left(\mathrm{g}\right)\to 2\mathrm{ZnO}\left(\mathrm{s}\right)+2{\mathrm{SO}}_2\left(\mathrm{g}\right) \\ \mathrm{Zinc}\mathrm{Oxygen}\mathrm{Zinc}\mathrm{Sulphur} \\ \mathrm{sulphide}\mathrm{oxide}\mathrm{dioxide} \end{gathered}$$
6. Therefore blast furnace is used for roasting.