Raw materials for the ferrosilicon production:
Raw materials like The quartz used inproduction of ferrosilicon industries has more than 97% Silicon dioxide, Silicon dioxide is a stable oxide that requires a lot of energy to reduction, such conditions are provided with relative ease in an electrothermic-carbothermic reaction.
Also, Silicon dioxide is an acidic oxide, metal oxides are generally basic and have a tendency to combine with silicon.
The existence of metal oxides more stable than silicon dioxide in the form of impurity forms slag, slag reduces the activity and makes it more difficult to reduction silicon dioxide. On the other hand, more unstable metal oxides, when the conditions for existence regeneration in the furnace are available, they are revived and join the metal phase and cause the formation of impurities in the product.
Impurities such as calcium, phosphorus and aluminum increase the possibility of decomposition of ferrosilicon alloys, therefore, in the existence of these impurities, more attention should be paid to the cooling speed.