What are pellets?
Pellets are the ground iron ore fibrnes converted to spherical shape balls having good physical properties for both bulk, mechanical transportation over long distances and also have excellent metallurgical properties similar or even better than lump ore. The pellets become a vital raw material for all types of Iron Making Units. They are made with technology that uses the powder that is generated during the ore extraction process, once considered waste.
What are they used for?
Affordable, high-quality raw materials for iron making are steadily decreasing on a global scale. This means that fine and ultra-fine iron ores will command an ever-larger share of iron ore sales in the future. For this reason, a growing number of iron and steel producers are looking into the possibility of increasing the portion of pellets in their production operations. The use of pellets, however, leads to a number of issues. Fluctuating prices on the world market can seriously affect cost-efficient ironmaking.
The pellets are used as raw material for Iron making in the plants as an alternate material for Sinter and/or Lump Ore.
The pellets are preferred over sinter and lump ore as their shape, size, strength and excellent designed metallurgical properties in Blast furnaces as burden. The use of pellets resulted in increasing the productivity of the iron making units without any capital investment. The designer pellets with known chemistry facilitate reduction in coke rate and the slag chemistry over the conventional burden.
Filter Cake (Iron-ore fitness concentrate) is received from the post beneficiation process. Other raw materials like Lime Stone, Dolomite, Bentonite, Coke & Coal is mixed with filter cakes in proportion as an additive and binder. Then the mixture passes through Pelletizing Discs to make green balls and then for screening are sent to the Drying -> Preheating -> Roasting process in a coal fired rotary Kiln to make the pellets. The finished pellets are then sent for cooling purpose and stored. The undersized and oversized balls are sent to the crusher for the further pelletizing process.