SU389146A1 - METHOD OF MELTING THE FERROVOLFRAM - Google Patents

Description

one

The invention relates to the production of ferrous metals, in particular ferroalloys.

There is a known method of smelting ferro-tungsten from a mixture consisting of tungsten concentrate, coke, iron shavings with slag refinishing with ferrosilicon.

When the slag is re-reduced by ferrosilicon, a prolonged holding of the melt in the furnace is necessary, which leads to high losses of tungsten and the formation of a siliceous metal.

In order to eliminate these drawbacks, a method has been proposed in which, after the ferrosilicon is loaded into the slag melt, aluminum is introduced containing a material of a fraction less than 5 mm, together with lime, taken in a ratio of (1-0.1): (1-0.5) and rasklav blow air under pressure of 5-6 atm. In order to bind the alumina produced during the reduction of tungsten and to increase the liquid mobility of the slag, 0, l-f-0.5 lime by weight of the waste is introduced together with the aluminum-containing material.

Example. 3.5 tons of a mixture of tungsten and scheelite concentrates were smelted on a furnace with a 3.5 mva transformer. Then ferro-tungsten was scooped out of the furnace for 2.5 hours with simultaneous proplavlepium concentrate.

After scooping the metal, 100 kg of pitch coke, 200 kg of granulated ferrosilicon and 150 kg of aluminum waste mixed with 50 kg of lime were introduced into the slag. 10 minutes after the introduction of the aluminum waste, the content of tungsten trioxide in the slag was 0.08%.

Fifteen minutes after the introduction of the aluminum waste, the slag was released from the furnace. After refining the alloy corresponded to B2 grade ferro-tungsten and contained 75.35% W, 0.43% Si, 0.21% Mn, 0.04% P, 0.22% C, 0.01% As.

The proposed method makes it possible to replace part of ferrosilicon with aluminum waste and shorten the duration of smelting.

Subject invention

The method of smelting ferro-tungsten from a mixture consisting of tungsten concentrate, coke with the re-reduction of slag by ferrosilicon, is distinguished by the fact that, in order to reduce tungsten in waste slag, after loading ferrosilicon, the slag is treated with a mixture of aluminum-containing material and lime, taken in a ratio (1 0.1): (1-0.5) with simultaneous purging of the melt with air.