Beneficiation & Pellet Plant Process Overview
The beneficiation and pelletization process is used to upgrade low-grade iron ore into high-quality pellets suitable for blast furnace or direct reduction (DRI) steelmaking. Below is a step-by-step breakdown of the process:
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1. Beneficiation Process (Iron Ore Upgradation)
The goal is to increase the iron content by removing impurities (gangue minerals like silica, alumina, and phosphorus).
# Steps in Beneficiation:
– Crushing & Screening:
– Run-of-mine (ROM) ore is crushed and screened to a suitable size.
– Primary, secondary, and tertiary crushers may be used.
– Grinding (Ball Mill / Rod Mill):
– Ore is ground into fine particles for liberation of iron oxides from gangue.
– Classification (Hydrocyclone / Spiral Classifier):
– Separates fine and coarse particles; coarse material may be re-crushed.
– Magnetic Separation (Low/High Intensity):
– Magnetic iron ores (magnetite) are separated using magnetic separators.
– Gravity Separation (Spirals / Jigs):
– Used for hematite/goethite ores where density differences help in separation.
– Flotation (For Silica/Alumina Removal):
– Chemicals are added to selectively float away silica/alumina from iron concentrate.
– Thickening & Filtration:
– Water is removed from the slurry to produce a filter cake (~8–10% moisture).
– Thickeners and vacuum filters are commonly used.
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2. Pelletization Process
The beneficiated iron ore concentrate is agglomerated into small balls (pellets) for efficient blast furnace use.
# Steps in Pelletization:
1. Mixing & Blending:
– Iron ore concentrate is mixed with binders (bentonite or organic binders) and additives (limestone/dolomite as flux).
2. Ball Formation in Disc Pelletizer / Drum Pelletizer:
– Moistened feed rolls into green pellets (~8–16 mm diameter).
3. Green Pellet Screening:
– Oversized/undersized pellets are recycled.
4. Drying & Pre-heating:
– Green pellets are dried at ~