Submerged Arc Furnace Smelting Ferronickel Production Process

Submerged arc furnace smelting of ferronickel primarily utilizes a high-temperature reduction reaction to convert the nickel in nickel ore into metallic nickel, which then forms a nickel-iron alloy with iron.

The production process generally includes raw material preparation, smelting, refining, and casting. In the submerged arc furnace, nickel ore is mixed with a reducing agent (such as coke) and reacted at high temperatures.

The quality and yield of the nickel-iron alloy depend on the raw material composition, smelting temperature, and operational control. Nickel-iron alloy is an important stainless steel raw material, and its production is crucial to the stainless steel industry.

Submerged Arc Furnace Smelting Ferronickel Production Process

Submerged arc electric furnace smelting of ferronickel uses high temperatures generated by electrical energy in an electric furnaces to reduce the nickel oxide in nickel ore to metallic nickel, which then combines with iron to form ferronickel. This is a highly efficient pyrometallurgical smelting method, particularly suitable for smelting laterite nickel ores. The typical process flow is as follows: nickel ore is crushed, screened, dried, and mixed with coal and flux. It is then pre-reduced in a rotary kiln to produce roasted sand, which is then sent to a submerged arc furnace for reduction smelting. Finally, the resulting crude ferronickel is refined and cast or granulated.

Process Flow

1. Raw Material Pretreatment: The nickel ore is crushed and screened, then mixed with pulverized coal (or coke) and fluxes such as limestone in appropriate proportions.

2. Rotary Kiln Pretreatment: The mixed raw materials are sent to a rotary kiln for high-temperature drying and pre-reduction, reducing some of the nickel oxide to metallic nickel, producing roasted sand containing approximately 20-30% nickel.

3. Submerged Arc Furnaces Reduction Smelting: The roasted sand is sent to a submerged arc furnace. Under the high temperatures generated by electrode discharge, carbon is used as a reducing agent to further reduce the oxides in the nickel ore, producing crude molten nickel. 

4. Refining: Crude ferronickel is fed into a refining furnace, where impurities (such as carbon, silicon, sulfur, and phosphorus) are removed through oxygen blowing and the addition of refining agents, resulting in refined ferronickel.

5. Casting & Granulation: The refined ferronickel is cast into ingots or granulated through processes such as water quenching before packaging and shipment.

Key Equipment and Technologies

Submerged Arc Furnace

SAF electric furnaces is the core equipment for ferronickel smelting. It utilizes self-baking electrodes to convert electrical energy into heat, providing a high-temperature environment.

Rotary Kiln

Used for drying and pre-reduction of nickel ore, its a key component of the Rotary Kiln-Submerged Arc Furnace (RKEF) process.

Refining Converter

Used for desulfurization and desiliconization of crude ferronickel. Common refining converters include bottom-blowing and side-blowing converters.

Technical Features

High Adaptability

The submerged arc furnace ferronickel production process is suitable for ores with various iron and nickel contents, capable of producing ferronickel with varying concentrations. 

High Efficiency

The RKEF process is a mature technology that enables thorough pre-reduction and efficient smelting of nickel ore.

Environmentally Friendly Recycling

The flue gas generated by the rotary kiln is treated in a waste heat boiler and dust removal and desulfurization process before being discharged. The slag can be used for water quenching, and the dust can be recycled.

If you have any questions or inquiries regarding metal smelting furnaces, such as submerged arc furnaces, please contact us for consultation.