• RMHP handles all raw materials EXCEPT coal — coal goes directly to Coke Ovens' Coal Handling Plant.
• Main functions: Unloading, Stacking, Screening, Crushing, Bedding, Blending, Reclamation, Dispatch.
• Customers: Blast Furnace (sized ore, quartzite), Sinter Plant (base mix, flux, coke), Calcining Plant (SMS grade LS & Dolomite).
• Wagon Tippler wagons: BOXN/BOXC/BOST/NBOY | Track Hopper wagons: BOBS/NBOBS.
• Homogenization stabilizes beyond 580 layers.
• Iron Ore Lump screened at 10×10 mm mesh to remove -10mm fraction.
• Pellets: fired at 1200–1350°C, size 8–20 mm, porosity 25-30%.

• Ash: 12% max | VM: 23-25% | MMR: 1.15-1.20
• Sulphur: <0.7% | FSI: 5-6 | Moisture: 7-9%
• Crushing Index: 80-82% of -3.2mm

• Heating coal in absence of air = Carbonization = Destructive Distillation
• Temperature stages: De-moisturization (≤250°C) → Softening (~300°C) → Plastic (350-550°C) → Re-solidification (>700°C) → Coke (~1000°C)
• CO Gas CV: ~4300 kcal/m³
• Wet quenching: ~5% moisture | Dry quenching: ~0.2% moisture (better quality)
• BF Coke size: +25 to -80mm | Nut Coke: +15 to -25mm | Breeze (-15mm) → Sinter Plant

• Acts as Fuel
• Acts as Reducing Agent
• Supports the burden inside furnace
• Provides Permeability

• Sintering = agglomeration of fines by incipient fusion caused by heat from coke.
• Hearth Layer: finished sinter of 10-20mm forms bottom layer on pallets.
• Ignition Furnace temp: 1150-1250°C; Max combustion zone: 1300-1350°C
• BTP (Burnt Through Point): ~400°C, found in second last wind box from discharge end.
• BF ideal sinter size: 5-40mm; -5mm is returned (in-plant return fines)
• Moisture in base mix: 7-8%

• Throat: Top burden surface
• Stack/Shaft: Ores heated, indirect reduction starts (<900°C)
• Belly/Bosh Parallel: Softening & melting
• Bosh: Reduction completed, ores melted
• Hearth: Hot metal & slag collected, tapped via tapholes

• Preheat air to 1000-1200°C before admission through tuyeres.
• 3-4 stoves per furnace. Two cycles: On Gas (heating) and On Blast (preheating air).

• 1% reduction in coke ash → 8-10 kg/thm reduction in coke rate
• 100°C increase in Hot Blast Temp → 2-3% coke saving

• LD = Linz & Donawitz (two Austrian cities where process was developed)
• Tap-to-tap time: ~45-50 minutes | Blowing time: 15-17 minutes
• End of blow temp: 1650-1690°C | Tapping temp: 1660-1680°C
• Oxygen pressure: 14-20 kg/cm²; purity >99.5%
• Scrap is used as coolant to maintain thermal balance

• ARS: Argon rinsing — homogeneous composition & temp, inclusion removal
• LF (Ladle Furnace): Arc heating, high ferro-alloy additions
• RH Degasser: Achieves H <2 ppm, C <30 ppm under vacuum
• Deoxidizers (increasing capacity): C → Mn → Si → Al (most powerful)

• Flow: Ladle → Tundish → Mould (Cu) → Secondary Cooling → Straightener → Cutting
• Mould: Copper — highest heat discharge capacity
• CC yield: >95% vs Ingot casting: ~80%

• Rolling = plastic deformation between rotating rolls; metal spread in width & elongated in length.
• Draft = reduction in thickness = h₀ - h₁ (initial - final thickness)
• Neutral point: where roll surface speed = stock speed.
• Hot rolling temp for steel: above recrystallization temp (~800-1200°C)
• Cold rolling: below recrystallization — work hardening; annealing required after

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