The iron ore manufacturing process involves several stages to convert raw iron ore into usable iron or steel products. Here’s a step-by-step breakdown:
1. Mining
– Iron ore is extracted from open-pit or underground mines.
– Common types of iron ore include hematite (Fe₂O₃) and magnetite (Fe₃O₄), with varying iron content (30–70%).
2. Crushing & Screening
– Mined ore is crushed into smaller pieces (lumps/fines) and screened to remove impurities.
– Low-grade ores may undergo beneficiation (enrichment) to increase iron content.
3. Beneficiation (Optional)
– Techniques like gravity separation, magnetic separation, or flotation remove gangue (waste material).
– The result is a higher-grade iron ore concentrate (~60–65% Fe).
4. Agglomeration (Pelletizing/Sintering)
– Fine ore is processed into pellets or sinter for efficient blast furnace use:
– Pelletizing: Ore fines are rolled into small balls and hardened by firing.
– Sintering: Fine ore is mixed with coke breeze and heated to form a porous mass.
5. Ironmaking (Blast Furnace or Direct Reduction)
# (a) Blast Furnace Route (Traditional Method)
– Iron ore, coke (carbon source), and limestone (flux) are fed into a blast furnace.
– Hot air (~1200°C) is blasted in, reducing iron oxide to molten pig iron (~4% carbon).
– Impurities form slag, which is removed.
# (b) Direct Reduced Iron (DRI / Sponge Iron)
– Uses natural gas or coal to reduce iron ore pellets/lumps in a shaft furnace (MIDREX, HYL process).
– Produces solid spong
ron (~90–94% Fe), later melted in an electric arc furnace.
6. Steelmaking
Pig iron or DRI is refined into steel:
# (a) Basic Oxygen Furnace (BOF)
– Pig iron + scrap steel + oxygen → removes excess carbon & impurities.
# (b) Electric Arc Furnace (EAF)
– Scrap steel or DRI melted using electric arcs; common for recycling.
7. Casting & Rolling
– Molten steel is cast into slabs, bille