The Impact of Charging and Batching on Electric Arc Furnace Energy Consumption

The Impact of Charging and Batching on Electric Arc Furnace Energy Consumption

What Impact does Charging have on Smelting Energy Consumption?

Properly loading the charge yard and ensuring that all requirements are met at the electric arc furnace are a requirement placed on charge yard loaders and a constant goal.

Rationalizing and distributing the charge according to the available material resources ensures a stable arc and smooth operation during the smelting process, resulting in rapid charge melting and reduced energy consumption per ton of steel. Conversely, improper proportioning will extend melting time and increase energy consumption.

Although the charge yard process is a supporting step in electric arc furnace steelmaking, the quality of the charge plays a key role in energy conservation.

Therefore, faced with complex and variable material resources, the question of how to rationally utilize them, maximize their characteristics, ensure good electrical conductivity between the electrodes and the metal charge, prevent charge bridging and significant charge collapse during the melting process, and thus meet furnace requirements is crucial.

What Charge Structure is Most Conducive to Reducing Smelting Energy Consumption?

The typical mix consists of 20% to 30% medium-sized slag steel, 6% to 10% pig iron or scrap molds, with a mix of raw material and off-cuts, and 20% cold-pressed briquettes covering the pig iron. Some believe that using more off-cuts is beneficial, but this is incorrect.

Using a large amount of low-carbon off-cuts can easily cause large areas of material to stick together during the melting process, compromising operations.

Some companies, solely driven by cost reduction, use more foamed material (or briquettes). This requires comprehensive consideration. Large quantities of briquettes (especially hot-pressed briquettes) contain a high concentration of oil, rust, and other impurities, which can lead to significant carbon loss during the melting process, often resulting in low melt carbon.

Sometimes, due to material resource constraints, there may be an excessive amount of slag steel, a low amount of off-cuts, or the material is too light, forcing yard loaders to use more slag steel. Slag steel contains many impurities.

The varying sizes and shapes of the lumps make them highly conductive, making them difficult to pack tightly and prone to electrode breakage. Therefore, there are three things to avoid during charging at the material yard: excessive use of cut ends, excessive use of slag steel, and excessive use of briquettes.

However, under certain objective conditions and considering comprehensive economic benefits, it is unavoidable to use more cut ends, more slag steel, and more briquettes. Clearly, rational coordination and scientific layout are essential during charging to minimize these unfavorable factors.