Deslagging and dephosphorizing method of electric stove

Abstract

The invention relates to a deslagging and dephosphorizing method of an electric stove, which adopts the following public technical scheme: slagging; deslagging for the first time; smelting by blowing oxygen, starting to deslag when the temperature of molten steel increases to 1500-1510 DEG C, and controlling the weight percentage of phosphorus to decrease to be not more than 0.015 percent; slagging for the second time; deslagging for the second time, i.e. starting to deslag for the second time when the temperature of molten steel increases to 1520-1550 DEG C, and controlling the weight percentage of the phosphorus to decrease to be not more than 0.010 percent; slagging for the third time; deslagging for the third time, and controlling the weight percentage of the phosphorus to decrease to be not more than 0.005 percent; slagging for the fourth time; and preserving heat by blowing oxygen, adopting steel and slag residual operation with a tapping amount accounting for 85-90 percent of the total capacity of the molten steel in a ladle, and forbidding slagging in a tapping process. By the method, the content of the phosphorus element in steel can be decreased to be below 0.002 percent, ultra clean soldering steel satisfying the requirement of users can be produced, a path for producing clean steel is provided for manufacturers without the pretreatment of the molten steel, and increase in investment is also not needed.

Description

Technical field [0001] The invention relates to a method for dephosphorizing steelmaking, and belongs to a method for dephosphorizing slagging of an electric furnace. Background technique [0002] With the continuous development of industries such as automobiles, machinery, and construction, the requirements for steel quality are constantly increasing. In order to meet the needs of users, steel mills are also constantly taking measures to reduce the content of harmful elements such as phosphorus and sulfur in steel. Reducing the sulfur content in steel is mainly achieved through hot metal pretreatment and refining processes. Reducing the phosphorus content in steel is mainly achieved through hot metal pretreatment and primary smelting processes, such as converter (or electric furnace) double slag dephosphorization, hot metal pretreatment and adjustment of refined slag and other methods for desulfurization. The main dephosphorization methods of electric furnace are single slag m...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to overcome the disadvantages that currently existing molten steel in electric furnace steelmaking contains relatively high phosphorus content, that is, the weight percentage is 0.01% or slightly lower, so that the cleanliness of the steel is low and cannot meet the needs of the market. It is to provide a A method for dephosphorizing electric furnace slag removal of high-quality clean steel that meets market demand by controlling the weight percentage of phosphorus in the tapped steel to ≤0.002%

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