SU432198A1 - METHOD OF CHANGE VANADIUM POWN IN OXYGEN CONVERTER - Google Patents

Description

one

The known method of redistribution of vanadium iron in an oxygen converter by blowing iron with oxygen or an oxygen-oxygen torch.

The disadvantage of this method is significant iron loss, especially during the processing of low-silicon iron, and the formation of vanadium slag with a liquid concentration of vanadium pentoxide.

In order to intensify the redistribution of low-silicon vanadium cast irons, to obtain low-iron vanadium slag and a high-carbon metal intermediate product, it is proposed to conduct oxygen blasting in the initial stage of the secondary iron to oxygen content of 0.1–0.2%, then enter the oxygen-oxygen torch with the oxygen ratio to the melt 0.4-1.0.

The blowing of vanadium iron begins with single oxygen through a multi-nozzle oxygen-fuel tuyere and leads it to obtain a vanadium concentration in the metal of approximately 0.20% or less, after which it is transferred to the metal blow by a reduced flame or a full flame. At the same time, during the period of oxygen purging, ferrous (up to about 60% Reooom) liquid-mobile slag with a vanadium pentoxide content of about 8-12% is rather quickly induced and quickly cooled,

supplements. This allows the pig iron to be purged, especially chemically cold, with a low silicon content, without sweeping the tuyeres and the converter throat, while the oxidation of the iron impurities proceeds as with a normal oxygen purge.

After the vanadium concentration in the blown iron reaches about 0.20% or less, full or partial combustion passes through the fuel-oxygen torch to the blast, while purging is conducted through the same oxygen-fuel tuyere with products of complete or partial combustion (CO2, HzO, CO, H2) . Such a composition of blowing contributes to a sharp slowdown in the oxidation of carbon, and the relative speed of devaptation (relative to the rate of decarburization) begins to increase. The oxidation rate of other elements is somewhat reduced. The iron oxide content in the scale also decreases. Due to the reduction of iron oxides, silicon, manganese, and vanadium n continue to oxidize, and the content of vanadium pentoxide in the slag increases.

When switching to purging with a reducing torch of complete combustion, the temperature of the metal rises slightly or remains unchanged (depending on the degree of reduction of iron oxides in the slag).

Thus, blowing vanadium iron with oxygen in the initial period of smelting allows you to quickly carry out the initial slagging process to produce liquid slurry slag, which contains a significant amount of iron oxides, and then, when switching to a flare blast, for example, reducing, it allows you to complete the process of de-development, to reduce the amount of oxides iron in the slag to 20-35%, to increase the content of vanadium pentoxide in it to 20-27% and at the same time to obtain an intermediate with a low residual content of vanadium and high carbon at a relative high temperature.

Subject matter

Method redistribution vanadium iron in the oxygen converter vklyuchayush, s his purge oxygen or fuel-oxygen flame, characterized in that, in order to intensify redistribution low silicate vanadium iron produced monozhelezistogo vanadium slag and metal of high precursor in the initial step of redistribution, purging lead oxygen to the content in the iron is 0.1–0.2% vanadium, after which a fuel-oxygen flame is introduced into the melt with an oxygen consumption coefficient of 0.4–1.0.