SU1063843A1 - Slag-forming alloying mix for smelting vanadium steel - Google Patents

Abstract

Slag-forming alloying mixture for smelting vanadium steel, vanadium converter board and lime, so that, in order to reduce the loss of alloying elements and improve the quality of steel, it additionally contains alumina with the following ratios, the following ratios are as follows. % :,. Van-Adium Converter Slag 30-40 Lime50-60 Alumina. 5-15

Description

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:. The invention relates to ferrous metallurgy, and more specifically to a method of smelting using slag-forming alloying mixtures of vanadium-containing steel with a high content of manganese. The known method of steelmaking, in which a mixture of vanadium converter slag (VSSH) and lime in the ratio 5: 1 -2: 1- is used to form oxidizing slag l. The resulting slag oxidizes carbon, manganese, and silicon, which leads to an increased carbon content of the alloying elements and complication of the smelting process. The closest to the proposed technical essence and the achieved result is the composition of the co-forming alloying mixture for smelting a mixture containing lime and vanadium converter slag 2. A disadvantage of the known mixture is the slow dissolution known in the initially formed manganic silicate slag melting, resulting in the formation of calcified basic slag and the reduction of manganese and vanadium are slowed down. A long course of redox processes reduces the quality of whether and reduces absorption of metal alloying elements object of the invention - reduction of losses of alloying elements, and improving the quality stsshi. This goal is achieved by the fact that the spack-forming alloying mixture for smelting vanadium steel containing vanadium converter slag and lime, additionally contains alumina in the following ratios, wt.%:. Vanadium converter slag30-40 Lime50-60 Alumina5-15 Experiments in industrial conditions have shown that using the proposed mixture for setting furnace slag in early periods of smelting allows, through the interaction of alumina introduced with the components of the primary slag and lime, to achieve a more rapid dissolution increased quantities to produce more basic homogeneous slags with lower viscosity. At the same time, the activity of vanadium and manganese oxides in the slag improves and the mass transfer conditions are improved, which creates catch for complete and rapid recovery of the reaction, the metal shutter reductant under nym smelting slag without increasing the duration and energy consumption are reduced As a result, loss of alloying elements is increased and the quality of steel. When the lime content in the slag-forming mixture is less than 50%, the resulting furnace slag has an insufficient basicity, the reduction reactions of va nadi and manganese proceed slowly, which leads to a high-enough content in the slag and a reduced quality of the metal. When the content of lime is more than 60%, the rate of dissolution and lime decreases, and an increase in basicity over the optimum does not lead to an increase in the positive effect achieved. The use of a slag-forming mixture with an alumina content of less than 5% has practically no effect on the rate of slag formation and the development of reduction reactions. With an increase in the alumina mixture in excess of 15%, no further improvement in the quality characteristics of the metal and a decrease in the concentration of oxides of the alloying elements in the slag were noted. Example. In an industrial electric-arc furnace with a basic lining and a charge, 5 tons of 110G13FTL steel are smelted by remelting non-oxidizing wastes. The alloying of steel with vanadium is carried out according to a known technology — control melts, and according to the proposed technology — experimental melts. The test and control melts were carried out under the same conditions for the composition and amount of the charge, fluxes and alloying materials, the state of the furnace, the power consumption and the duration of the heat. In the control melts, the slag-forming surface of VKSH and lime in the ratio of 1: 1 is introduced into the filling or during the float period. The amount of vanadium slag is determined by calculation, it is 30 kg. Per ton of metal dumping. In the pilot melts, the slag-forming mixture is made up of VKSH (35%), lime (48-62%), alumina (3-17%). - The amount of vanadium slag is 29 kg per ton of metal dumping, taking into account the increased absorption of vanadium. . After melting 25 minutes, aging and fine-tuning by chemical composition, samples of metal and slag are taken for chemical analysis and the metal is released into the ladle. to determine the physicomechanical properties of the metal, they are selected in the middle of the casting. . The obtained average results are shown in the table. The introduction of alumina in the slag-forming mixture, sitting down in the smelting process, contributes to more rapid slag formation, dissolution in the slag, and more lime

better recovery of oxides of alloying elements from slag.

The effective content of alumina is 5-15%, and 50-60% lime. At other concentration parameters of the slag-forming mixture, the effect efficiency is significantly reduced.

Improving the quality of the slag causes an increase in the physicomechanical characteristics of the steel.

The application of the proposed demolition for the smelting of vanadium scrap metal AeoVolit 5 I to reduce the consumption of the alloy of their ferroalloys and to improve the quality of Wahppeamol steel.

23.8 21.3 32.4 2.1 Istrests-VKSH 40 on Lime. 60 29.8 14.1 32.6 7.5 Pre-VKSH 42 Lagaeva 48 19.0 0.32 The remaining 15.7 9 , 17 Else

Claims (1)

Slag-forming alloying mixture for smelting vanadium steel, containing vanadium converter slag and lime, a rain and smelter, in order to reduce the loss of alloying elements and improve the quality of steel, it additionally contains alumina with the following ratios of components, wt .% :,. Vanadium Converter Slag Lime Alumina to