The process of smelting stainless steel by electric arc furnace returning to oxygen blowing method

Abstract

The invention relates to the technical field of stainless steel smelting, and discloses a process of smelting stainless steel in an electric arc furnace with a back blowing method. For some problems in stainless steel production, combining with production practice, the process employs process technology and operating means, such as high silicon (silicon adjusted to 1.0-1.5 %), high nickel (controlled to about 10 %), high temperature, high pressure (1.5-1.8 MPa), continuous double-tube oxygen blowing for 18-22 min, real-time alloy feeding for fast reducing molten steel temperature within the furnace and reasonable power supply, so that the utilization rate of the high alloy steel return scrap reaches above 90 % during smelting, the recovery rate of chromium reaches above 95 % during the whole smelting process, the smelting oxygen blowing time is shortened by about 40 min. The process of smelting stainless steel in an electric arc furnace with a back blowing method can greatly improve the service life of the furnace lining, efficiently reduce production cost and labor cost of each worker and create a very substantial economic benefit.

Description

technical field [0001] The invention relates to the technical field of stainless steel smelting, in particular to a process for smelting stainless steel by an electric arc furnace returning to the oxygen blowing method under the conditions of high silicon, high nickel, high pressure, high temperature and the like. Background technique [0002] The process of smelting stainless steel by electric arc furnace returning to oxygen blowing method has been widely used in the field of stainless steel production. Its purpose is to recover high-value metal elements such as chromium, nickel, molybdenum, etc. in scrap alloy steel, so as to reduce the cost of smelting production. In the long-term production practice, the following problems have been found in the production of nickel-chromium stainless steel by smelting the electric arc furnace back to the oxygen blowing method: [0003] (1) The amount of high-alloy steel returned to the electric arc furnace for smelting stainless steel b...

AI Technical Summary

Problems solved by technology

[0003] (1) The amount of high-alloy steel returned to the electric arc furnace for smelting stainless steel by oxygen blowing method is low, generally 40% to 60%, and the recovery rate of the alloy is not high, and the smelting cost is high;

[0004] (2) The electric arc furnace returns to the oxygen blowing method to smelt stainless steel. In the process of oxygen blowing and decarburization, the chromium in the molten steel will also be oxidized. The more oxidation burns, the composition of the tapping liquid cannot be guaranteed, especially the content of carbon and chromium is not easy to control;

[0005] (3) The temperature of the molten steel is not well controlled during the production process of the electric arc furnace returning to the oxygen blowing method for smelting stainless steel. Improper operation of voltage and current will cause short-arc operation, unreasonable use of voltage and current, and low alloy recovery rate, which seriously affects production. process and product quality;

[0006] (4) When the electric arc furnace returns to the oxygen blowing method to smelt stainless steel, the temperature in the furnace continues to rise during blowing, which makes the furnace lining overheated for a long time. The high-temperature slag erodes the furnace lining seriously, causing damage to the furnace lining. It is necessary to quickly repair the furnace with brine magnesia at high temperature Or rebuild the furnace, the operation of repairing the furnace is complicated, time-consuming and labor-intensive

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