How is chromite ore prepared before it is smelted in a furnace?

While much high-quality chromite ore is rich enough to be used directly in smelting, finely divided ores do not smelt efficiently and require preparation to improve their performance in a furnace.1

To prepare these finer ores, the material is typically agglomerated to ensure it can be used effectively. This process often involves blending the fine ore with fluxes and coke, which serves as the primary source of carbon. Once blended, the mixture is frequently preheated or "prereduced" before being charged into an electric smelting furnace.1

In commercial practice, the presence of impurities such as magnesia, alumina, and silica in the ore may also necessitate the addition of silica as a flux during the smelting process to help lower the melting point of the resulting slag.2