What is the manufacturing process of ferro silicon?

The manufacturing process of ferro silicon involves several steps, primarily utilizing raw materials such as silica (SiO2), coke (carbon), and iron scraps. Here's a general overview of the process:

1. Raw Material Preparation:

   • Silica (usually in the form of quartz or silica sand), coke (carbon), and iron scraps are the primary raw materials used in ferro silicon production. These materials are carefully selected and prepared to ensure optimal chemical composition and purity.

2. Smelting Furnace Charging:

   • The raw materials are charged into a submerged arc furnace (SAF) or an electric arc furnace (EAF) in specific proportions according to the desired ferro silicon composition. The furnace operates at high temperatures, typically ranging from 1800°C to 2000°C.
   • 
     

3. Heating and Reduction:

   • Once the furnace is charged, it is heated using electric arcs or other heat sources to reach the desired operating temperature. At these high temperatures, the carbon in the coke reacts with the silica to produce carbon monoxide gas (CO) and elemental silicon (Si). Additionally, iron from the iron scraps reacts with silicon to form ferro silicon alloy.

4. Alloy Formation:

   • The reduction reactions occur within the furnace, leading to the formation of ferro silicon alloy. The alloy typically contains varying percentages of silicon (usually around 15% to 90%), along with iron and other minor elements depending on the composition of the raw materials and process parameters.

5. Tap Out and Casting:

   • Once the desired alloy composition is achieved, the furnace is tapped to remove the molten ferro silicon from the furnace hearth. The molten alloy is then cast into molds or allowed to solidify into ingots, depending on the intended final product form.

6. Cooling and Solidification:

   • The cast ferro silicon undergoes controlled cooling and solidification to ensure the formation of a homogeneous structure and prevent the formation of undesirable phases or defects.

7. Crushing and Sizing:

   • After solidification, the ferro silicon ingots or blocks are crushed into smaller pieces and then further sized to meet specific customer requirements. This process may involve crushing, screening, and sorting to achieve the desired particle size distribution.

Throughout the manufacturing process, strict quality control measures are implemented to ensure the consistency, purity, and performance of the ferro silicon product. This includes monitoring of raw materials, process parameters, and final product characteristics to meet industry standards and customer expectations.