DC Submerged Arc Furnace Equipment Introduction

1. Core Working Principle

1. External alternating current is converted into stable direct current through the rectification system. The current passes through the cathode electrode at the top of the furnace, forming an arc between the cathode and the anode at the bottom (or wall) of the furnace.
2. The high temperature generated by the arc (up to 1600-2000℃), together with the resistance heat of the furnace charge itself, heats the charge to melt it and trigger reduction reactions, producing the required alloy products.
3. Compared with alternating current, direct current has no current zero-crossing phenomenon, so the arc is more stable, the heat is concentrated without skin effect, and the energy utilization rate is significantly improved.

2. Core Components of the Equipment

3. Key Technical Advantages (vs. AC Submerged Arc Furnace)

1. Significant Energy Saving: The power factor is stable above 0.95, and the power consumption per ton of product is reduced by 5%-15%; electrode consumption is reduced by 30%-50%, greatly lowering consumable costs.
2. Higher Smelting Efficiency: The arc is stable without fluctuation, the temperature field in the furnace is uniform and the heat is concentrated, the material melting speed is faster, the daily iron output can be increased by more than 30%, and the furnace bottom is less prone to rising.
3. Extended Equipment Service Life: The furnace lining is corroded uniformly, without the "hot spot" corrosion common in AC furnaces, and the service life of the furnace lining can be extended to more than 5 years (the industry average is 3-4 years).
4. Good Power Grid Compatibility: It has little harmonic interference to the power grid, eliminating the need for large-scale reactive power compensation devices and reducing supporting equipment investment.
5. Excellent Environmental Performance: The closed design enables full flue gas collection, facilitating dust removal and waste heat recovery, and significantly reducing the emission of dust and harmful gases.

4. Typical Application Scenarios

• Ferroalloy Smelting: Ferrosilicon, silicomanganese alloy, high-carbon ferrochrome, etc., especially suitable for smelting high-melting-point and difficult-to-reduce ores.
• Industrial Silicon Production: Stable temperature in the furnace leads to more sufficient reactions and higher product purity.
• Calcium Carbide Smelting: Allows deep electrode operation with stable furnace conditions, greatly improving production efficiency.
• Solid/Hazardous Waste Treatment: Some models can be used for harmless smelting and recovery of metal solid waste.

5. Core Technical Parameters (Take a typical 30MVA DC submerged arc furnace as an example)