SU113871A1 - Electric furnace for smelting electrocorundum, mono alumina and other similar materials - Google Patents

Description

The known technological method of producing corundum, mono-corundum and other similar materials is carried out by a discontinuous "block process." However, such a process is uneconomical, since it is difficult to create a sufficient volume of liquid melt, which causes an increase in the electrical power released in the melt and an insufficiently stable melt discharge, since as the amount of the melt in the bath increases, its temperature decreases melt is constant, and the weight of the melt increases).

The described electric smelting furnace allows the melt to be maintained in a liquid state, refined and melted continuously, which results in improved furnace productivity, reduced specific energy consumption and ensures a steady smelting process with metal release. This is achieved by using three fixed electrodes in an electric furnace, the lower ends of which are immersed in the melt, and the upper ones are electrically connected in parallel to the moving electrodes. The moving electrodes carry out the smelting process, while the stationary ones serve to maintain the melt in a liquid state and its refining.

FIG. 1 Dan section, described the furnace; in fig. 2 - electrical circuit diagram.

The furnace consists of a lined metal casing} with a hearth and six coal electrodes. Three movable electrodes 2 are located along the vertices of an equilateral triangle and are equipped with electric winches for lifting and lowering them. Three stationary carbon electrodes 3 are located at the vertices of another equilateral triangle and are distant from the moving electrodes; they are equipped with a device for their suspension and periodic replacement. All electrodes are supplied with a three-phase current of industrial frequency.

In the hearth of the furnace there is a hole with a slope towards

No. 113871-2 -

letke 4 dl ferroalloy. A letting outlet 5 for draining the middling, consisting of coal blocks, has electrical contact with one of the fixed electrodes, which stands on the taphole embrasure (Fig. 2). In the casing / there is a coal gasket 6 and fireproof brick insulation 7.

Work in continuous smelting is as follows.

The charge materials are fed to the bath, melted by an electric arc created by three moving electrodes; stationary electrodes are under voltage, but due to the absence of a closed electrical circuit (as long as there is no melt), they do not participate in the process.

As the melt appears, a part of the electric current begins to flow along the circuit: stationary electrodes - melt. The arc smelting process is supported by moving electrodes; the amount of the melt increases and as this increases the current (and hence the power) passing through the melt, refining it and maintaining it in a liquid state.

When the volume of the melt reaches the required value, its production begins. The melt is located in the immediate vicinity of the tap hole (since it itself serves as a conductor and means of heating) through which the product is released.

The movable electrodes go back down, and the product starts to float.

The moving electrodes come back into contact with the melt.

Subject invention

An electric furnace for smelting electrocorundum, mono-corundum and other similar materials equipped with three movable electrodes, characterized in that, in order to obtain a continuous smelting process and maintain the melt in a liquid state and its refining, three fixed electrodes are installed, the lower ends of which are immersed in the melt, and the top - are electrically connected in parallel to the moving electrodes.