Pre-deoxygenation method and device for spraying blowing of carbon powder in tapping hole of converter

Abstract

The invention belongs to the technical field of steel and iron metallurgy, in particular to a pre-deoxygenation method and device for spraying blowing of carbon powder in a tapping hole of a converter. A plurality of carbon powder spraying pipes are installed in a tubular refractory material of the tapping hole of the converter, in the tapping process of the converter, the carbon powder is blow into tapping steel stream in a spraying manner, the carbon powder and dissolved oxygen [O] in molten steel have a reaction, and CO is generated. By means of the carbon powder spraying pipes in the tapping hole, the carbon powder is blown into the tapping steel stream in the spraying manner for deoxygenation, a deoxygenation product is CO, the gas state CO can escape from the tapping steel stream andis discharged into the atmosphere, no inclusion is left in the molten steel, and no harm is caused to the steel material quality. The carbon powder has large deoxygenation space and has very high deoxygenation capacity, and more than 40% of dissolved oxygen in the molten steel can be removed. Compared with deoxygenation performed through aluminum, about 90% of the deoxygenation cost can be savedby adopting the carbon powder; and compared with deoxygenation performed through silicon, about 80% of the deoxygenation cost can be saved by adopting the carbon powder.

Description

Technical field [0001] The invention belongs to the technical field of iron and steel metallurgy. Specifically, the invention relates to a pre-deoxidation method and device for injecting carbon powder into the tapping port of a converter. Background technique [0002] The converter has a strong ability to remove C and P. With the improvement of customer requirements for steel quality, most steel plants carry out deep removal of P during the smelting of converters. The end point of converter smelting is controlled by P≤0.015%, which is to control phosphorus. The lower content requires an increase in oxygen supply for oxidative dephosphorization, and the oxygen in the molten steel is controlled to 400-600 ppm, which causes serious peroxidation of the molten steel. In order to achieve the effect of deep dephosphorization, the converter generally adopts the method of blowing in excess oxygen. In addition to ultra-low carbon steel, the carbon in the molten steel at the end of the conv...

AI Technical Summary

Problems solved by technology

Although this method can replace part of the aluminum deoxidizer with carbon powder for deoxidation in the early stage of the converter tapping process, but in the middle and later stages of the converter tapping process, due to the deoxidation of aluminum deoxidizers and alloys with strong deoxidation ability Added, so that the main deoxidizer is still the aluminum deoxidizer and the alloy with strong deoxidation ability, the carbon powder can not achieve the deoxidation effect

And due to the low density of carbon powder, after being added to the ladle, the carbon powder that has not been dissolved in the molten steel will float to the surface of the molten steel, and the deoxidation kinetics conditions are relatively poor.

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