Views: 0 Author: Site Editor Publish Time: 2026-02-04 Origin: Site
Ferromanganese is categorized by carbon content into high carbon ferromanganese (approx. 7% C), medium carbon ferromanganese (approx. 1.0–2.0% C), and low carbon ferromanganese (max. 1.0% C). Among these, low carbon ferromanganese delivers higher economic value and is widely used across the steelmaking industry, foundry industry, and related sectors.
Traditional production of low carbon ferromanganese often relies on the electro-silicon thermal method, where carbon content in raw materials like ferrosilicon manganese can compromise product quality and increase costs. To overcome this, we have developed an advanced, cost-effective approach: smelting low carbon ferromanganese using a shaking ladle with ferrosilicon powder and high carbon ferromanganese slag.
High carbon ferromanganese slag is a by-product of carbon ferromanganese production, with the following typical composition:
| Component | MnO | SiO₂ | CaO | MgO | Al₂O₃ |
|---|---|---|---|---|---|
| % | 31.1 | 22.33 | 23.68 | 4.22 | 12.68 |
High MnO content promotes effective reaction in the shaking ladle.
Favorable slag alkalinity supports efficient metallurgical response.
A slight drawback is the lower molten temperature (around 1100°C), which requires careful thermal management.
In a 5m³ shaking ladle, molten high carbon ferromanganese slag reacts with ferrosilicon powder (FeSi75%) according to the reduction reaction:
2(MnO) + [Si] → 2[Mn] + (SiO₂)
Expands the reaction interface between raw materials.
Accelerates ion diffusion.
Ensures thorough mixing of slag and ferrosilicon alloy.
Utilizes sensible heat from the slag and desiliconization reaction heat, enabling 8–10 minutes of autonomous reaction without external heating—significantly reducing power consumption and smelting time.
This method consistently yields low carbon ferrosilicon manganese with:
Carbon content below 0.2%
Manganese: 65–67%
Silicon: 18–20%
Loading – Transfer molten high carbon ferromanganese slag into the shaking ladle, then add 1 ton of FeSi75% powder.
Shaking – Start the ladle at 200–300 rpm. As the reaction intensifies, gradually add more molten slag while maintaining slag alkalinity between 0.9–1.0 and ensuring the fill level does not exceed two-thirds of the ladle volume.
Reaction Period – Shake for 5–20 minutes, then allow the mixture to stand for 2–3 minutes.
Separation & Refining – Pour the alloy into an electric refining furnace for final smelting. The slag is water-quenched for disposal or further use.
Parallel Processing – Simultaneously, prepare silicon manganese alloy in a separate shaking ladle following the same procedure, then transfer it to the refining furnace to complete low carbon ferromanganese smelting.
Temperature Control – Maintain slag temperature by covering molten slag to minimize heat loss. Synchronize tapping between the submerged arc furnace and refining furnace to prevent temperature drop.
Raw Material Specifications – Use ≥6 tons of molten slag per 5m³ ladle. Maintain a 1:8 ratio of ferrosilicon powder to slag. Ensure slag alkalinity of 0.8–1.2 and MnO content ≥30%.
Rotation Speed – Start slow, increase to maximum speed once the reaction stabilizes, and reduce speed when noise from the ladle indicates completion.
Process Timing – The shaking reaction typically lasts 5–7 minutes. Completion is signaled by:
Diminished flame at the ladle mouth
Sharp drop in reaction gas emission
Minor molten metal splashes
High carbon ferromanganese slag from electric furnaces is characterized by high Mn/Fe ratio and low impurities, making it an excellent raw material for ferrosilicon manganese alloy production.
By adopting this shaking ladle method, manufacturers can:
Fully utilize high carbon ferromanganese slag
Enhance low carbon ferromanganese quality
Reduce overall production costs
Achieve carbon levels below 0.2% efficiently
