SU1397545A1 - Carbon-containing plug for forming secondary anode of aluminium electrolyzer - Google Patents

Abstract

The invention relates to the field of non-ferrous metallurgy, in particular, to the production of aluminum in electrolytic cells with self-firing anodes, and is intended to form a secondary anode when the anode posts are interchanged. The aim of the invention is to reduce energy consumption by reducing the contact-to-voltage drop across the pin-anode and improving working conditions. The carbon-containing plug consists of the upper one. And the lower two parts and the shell. 3. The execution of the parts of the plug with different binder contents, and the presence of the shell on the lower part contribute to the creation of a tighter adhesive contact plug-anode. 1 ill., 1 tab. I (L co. 4 SL

Description

The invention relates to non-ferrous metallurgy, namely, to the production of aluminum in electrolytic cells with self-burning anodes, and is intended to form a secondary anode when the anode posts are interchanged.

The circuit of the invention is reduction, energy consumption by reducing the contact-voltage drop across the pin-anode, and improving working conditions.

The drawing shows a carbon holding tube for forming the secondary anode of an aluminum electrolysis cell, a general view,

The carbon-containing plug has an upper part 1 made of an anodic mass with a binder content of 35-40%, by volume 25-35% of the total volume of the stopper, and a lower part 2 with a binder content of 20-28% and fitted with a shell 3 of The binder, whose thickness is 1.5-3% of the diameter of the lower base of the stopper.

Example. A portion of the mass with an increased binder content is dosed to the formed lower part with a binder content of 20-28% in the form. After solidification, the on-surface of the lower part by spraying or dipping into the straightened binder, for example, coal tar pitch, is applied with a layer with a thickness of 1.5-3% of the diameter of the lower base of the cork. A layer of pitch can also be applied to the inner surface of the mold before forming the bottom of the cork. After pulling out the pin, the plug is lowered into the hole. At the same time, the layer of the binder on the surface of the cork melts and, playing the role of lubricant, facilitates the tight installation of the cork in place, filling in also the unevenness of the surface of the sub-bolt, and thus creating a pre-joint for strong contact.

The upper part 1 of the plug also enters the plastic state. The mounted chuck is lowered to the upper surface of the lower part 2, squeezing out the plastic mass of the upper part 1 into the gap between its surface and the surface of the hole in the anode. A dense filling of the gap occurs.

Upon further coking of the plug, the surface layer of the binder filling the cracks and gaps between the plugs

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and a hole, causing a mechanical mechanical and electrical contact between the plug and the anode, the same effect for creating the pin-anode contact creates a coked upper part 1 of the plug.

The table shows examples of the optimal binder content in the upper 37% and lower 24% parts with an upper volume of 30%.

With a binder content of 30% in the anode mass of the lower part, the voltage drop significantly increases to 384 mV and the power consumption to 13,100 kWh / t A1.

The anode mass with a binder content of 18% in the lower part of the tube has an extremely low mechanical strength, which precludes its use.

The upper part of the plug with a high content of 1: the binder in the process of forming the secondary anode enters the plastic state and, when installed, the pin fills tightly the gap between its surface and the anode.

The lower part of the plug with reduced binder content is the basis on which the pin is mounted. During coking of the cork, the surface layer of the binder, having melted, fills the cracks and gaps between the cork and the anode.

This provides a good mechanical contact plug - anode, which reduces power consumption per ton of aluminum.

When using a carbon-containing cork, the operation of loading the binding mass is excluded, the melting time and shrinkage of which is longer than the upper part of the previously formed composite cork, into the under-hole. Reducing the melting time of the upper part of the cork allows reducing the number of simultaneously removed pins, speeding up the rearrangement operation, increasing the accuracy of their installation on the new horizon and reducing the amount of harmful resinous and carcinogenic substances by 8-13%.

All of this reduces labor costs for redeploying pins and improves working conditions.

The presence of a sheath from a binder on the lower part contributes to the creation of a tighter adhesive contact, the plug – anode, and, consequently, the improvement of electrical contact.

Claims (1)

Invention Formula A carbon containing plug for forming the secondary anode of an aluminum electrolysis cell made of an anode paste with a binder, characterized in that, in order to reduce energy costs by reducing the contact voltage drop the pin is the anode and the working conditions are improved, it is made of two parts in height, the upper part is 25–35% of the total volume and contains 35–40% of the binder, the lower part is filled with a sheath of 1.5 binder thickness -3.0% of the bottom diameter, and the binder content in the lower part is 20-28%. The voltage drop in the anode, mV Electricity consumption, kW. h / t A1 360 362 The pins are not placed on the horizon. 13217 12860 12910