Low-cost converter steelmaking deoxidization process

Abstract

The invention discloses a low-cost converter steelmaking deoxidization process. The process is characterized in that in the converter steel tapping process, carbon powder and a composite deoxidization agent are added for segmented deoxidization, the content of total oxygen in molten steel is reduced by controlling the deoxidization occasion and optimizing the steel tapping deoxidization operation process, the low-price carbon powder and the composite deoxidization agent are used for replacing a traditional aluminum and iron deoxidization agent, deoxidization cost can be greatly reduced, and meanwhile, non-metallic inclusion is reduced. By means of the deoxidization process, the ratio of inclusion, with the level smaller than or equal to 1.5, in steel is increased to 98.21%, the continuous casting fluctuation flow rate is reduced to 0.32%, the deoxidization cost of each ton of steel is reduced by 1.58 RMB yuan, and profit margin is increased for enterprises while steel quality is improved.

Description

technical field [0001] The invention belongs to the technical field of steelmaking production, in particular to a low-cost converter steelmaking deoxidation process. Background technique [0002] Excessive oxygen is dissolved into the molten steel at the end of converter steelmaking, and the excess oxygen precipitates out when the molten steel solidifies to form oxide inclusions and bubbles, which directly affect the quality of cast slabs and steel products. Therefore, in the steelmaking process, it is necessary to reduce the oxygen content at the end of the converter, which is the source of inclusions in the steel. At present, the deoxidation methods used in the domestic industrial steelmaking production process mainly include: aluminum deoxidation method, adding metal aluminum to the molten steel in the ladle when tapping the steel. This deoxidation method is relatively simple, but the deoxidation effect is unstable, and Al is easy to form 2 o 3 Such non-metallic inclusi...

AI Technical Summary

Problems solved by technology

At present, the deoxidation methods used in the domestic industrial steelmaking production process mainly include: aluminum deoxidation method, adding metal aluminum to the molten steel in the ladle when tapping the steel. This deoxidation method is relatively simple, but the deoxidation effect is unstable, and Al is easy to form 2 o 3 Such non-metallic inclusions, small particles of such inclusions are not easy to float up into slag, resulting in an increase of non-metallic inclusions in steel, and the price of aluminum exceeds 10,000 yuan / ton, and the cost of steel per ton is high; carbon deoxidation method is added to the ladle before tapping For carbon-containing materials, this deoxidation method is relatively simple, and the deoxidation effect is also unstable, which is prone to safety hazards caused by molten steel "turning over" and will increase the carbon content of molten steel; there are also methods such as silicon-calcium alloy deoxidation method, core wire deoxidation method, etc. , although the deoxidation effect of these methods is better, but the cost is higher

[0003] For example, the patent "Converter Steelmaking Deoxidizer" (application number: 89105941.5) discloses that a deoxidizer is put into the ladle for deoxidation before tapping, and the composition of the deoxidizer is (% by weight): 65-96% CaC 2 , 4-35% SiC, this method is due to the deoxidation ability of Si, Ca>C, Si and Ca are deoxidized first in molten steel, and carbon is easy to react incompletely to produce carbon increase; patent "a low-cost electric arc furnace tapping deoxidation process "(Application No.: CN200710031301) discloses a three-step deoxidation process of carbon powder pre-deoxidation, ferrosilicon shallow deoxidation, and aluminum block deep deoxidation. Although this method can reduce the deoxidation cost, a large amount of aluminum is added to produce Al 2 o 3 Such inclusions are not easy to remove by slag, and increase the viscosity of molten steel, which is easy to cause flocculation in the casting machine

Images