SU872605A2 - Lining of cathode part of aluminium electrolyzer - Google Patents

Description

(54) LIGHTING OF CATHODE PART OF ALUMINUM

one

The invention relates to non-ferrous metallurgy, in particular, to the production of aluminum by melt electrolysis, and concerns the design of the cathode device of an aluminum electrolysis cell.

According to the main auth. No. 594212 and the well-known lining of the cathode part of the aluminum electrolysis cell, which includes heat insulation and fire-resistant layers, JQ between which is made a layer of red brick fl}.

During the operation of an electrolytic cell with such a lining, the melt penetrates through coal blocks and interacts with a layer of red brick, turning it into a plastic mass with a softening temperature of 780-820 C.

The formed plastic diaphragm takes on vertical forces developing in the cathode of the electrolyzer and prevents the destruction of the cathode blocks. The service life of the cathode lining increases i

However, as the life of the cell increases, the electrolytic cell comes to a point when the plastic layer in the central part of the lining is supersaturated with the components of the melt, as a result of which the softening temperature of this layer increases,. ELECTROLYSERA

consequently, a decrease in the efficiency of the diaphragm.

Since impregnation, fluorine salts lining and the interaction of the latter with red brick occurs in the central part of the cathode, partially impregnation reaches the underlying layers of masonry, which leads to the destruction of the refractory and loss of thermal insulation properties.

The aim of the invention is to increase the service life of the lining due to the possibility of recycling refractory material after dismantling the cathode.

The goal is achieved by the fact that the red brick layer is laid differentially in thickness with the ratio of the thickness of the layer at the projection of the anode on the cathode to the thickness of the layer at the periphery from 2: 1, 3: 1.

The drawing shows the cathode portion of an aluminum electrolytic cell with a lined section.

The device includes an onboard coal block 1, located on the fireclay flap 2, a refractory heat-insulating backfill 3, bottom blocks 4, interconnected by seams 5 of the bottom mass and embedded in

They are made of steel cathode rods 6 and mounted on a heat insulating layer 7 made of fireclay bricks, a thickness-differentiated layer of red brick 8 and a refractory layer 9 of diatomite brick.

During the operation of the electrolyzer, the melt penetrates through the coal blocks and interacts with a layer of red brick differentiated in thickness. Increasing the thickness of the red brick in the central part of the lining (where the anode is projected onto the cathode) allows to obtain a multilayer plastic mass that prevents the destruction of the refractory material and allows it to be used again.

Increasing the layers of red brick more than three is not advisable, since the thermal equilibrium of the electrolyzer is disturbed. The use of the invention allows to increase the service life of electrolyzers.

Total savings on the electrolysis shop will be 167.3 thousand rubles.

Claims (1)

Invention Formula Lining of the cathode part of the aluminum electrolyzer, auth.St. No. 594212, characterized in that, in order to increase the service life of the lining, additional layers of red brick are laid on it at the anode projection onto the cathode, and the ratio of the thickness of the brick layer at the anode projection onto the cathode 5 to the thickness of the layer of brick on the periphery is (2-3): 1. Sources of information taken into account in the examination 1. USSR author's certificate 0 No. 594212, cl. C 25 C 3/08, 1975.