flow sheet of ferro manganese proccess

Here is a simplified flow sheet for the production of Ferro Manganese (FeMn), which is typically produced in a submerged arc furnace (SAF) using either the carbothermic reduction process (for high-carbon FeMn) or a silicothermic process (for medium/low-carbon FeMn).

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1. Raw Material Preparation
– Manganese Ore (MnO₂/Mn₃O₄) – Crushed, washed, and screened to remove impurities.
– Iron Source (Iron ore/scrap/Fe-rich slag) – Added to adjust the Fe:Mn ratio.
– Reductant (Coke/Coal/Charcoal) – Used as a carbon source for reduction.
– Flux mestone/Dolomite) – Added to form slag and remove impurities.

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2. Blending & Sintering/Pelletizing (Optional)
– Raw materials are blended to achieve the desired Mn/Fe ratio (~80% Mn, ~15% Fe).
– Some plants sinter or pelletize the mix to improve furnace efficiency.

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3. Smelting in Submerged Arc Furnace (SAF)
# (a) High-Carbon Ferro Manganese (HC-FeMn, ~6-8% C)
– The blended charge is fed into an electric arc furnace (~1200–1400°C).
– Reduction reactions occur:
\[
\text{MnO}_2 → \text{Mn}_2\text{O}_3 → \text{Mn}_3\text{O}_4 → \text{MnO} + \text{CO}↑
\]
\[
\text{MnO} + \text{C} → \text{Mn} + \text{CO}↑
\]
\[
\text{Fe}_2\text{O}_3 + \text{C} → \text{Fe} + \text{CO}↑
\]
– Molten metal (~75–85% Mn, ~6–8% C) and slag are tapped periodically.

# (b) Medium/Low-Carbon Ferro Manganese (MC/LC-FeMn, ~1–2% C)
– Produced by refining HC-FeMn using silicothermic reduction:
\[
2\text{MnO} + \text{Si