SU1236005A1 - Method of starting electrolyzer for refining aluminium - Google Patents

Description

The invention relates to the field of refining non-ferrous metals, in particular to the electrolytic refining of aluminum.

The aim of the invention is to increase the service life of the cell and reduce costs by eliminating the anode effect.

The purpose of the invention is achieved in that according to the method of starting an electrolyzer for aluminum refining, including heating of the coal hearth and side magnesite lining, installing cathodes, casting in the shaft of the cathode aluminum unit and connecting it to the DC circuit, filling the electrolyte, and then the anode alloy, The surface is covered with copper sheets before the electrolyte is filled in, but it does not. The flatness of the sheet covering to the total bottom area is 0.1-0.8.

When the ratio of the area of the sheet coating to the total weight of the plate is less than 0.1, an anode effect occurs on the electrolyzer. In the case when the ratio exceeds 0.8, the adjustment of the composition of the anodic alloy in the post-start period becomes more complicated and increases with labor costs

The copper sheets deposited on the bottom of the copper electrolytically dissolve and the honey is deposited on the cathode aluminum, forming a ligature that is used in the post-launch period to prepare the anode alloy. As a result of the dissolution of the sheet coating and the higher current on it, the current density on the anode surface free of plates , sharply decreases and becomes significantly lower than the critical current density, which is the cause of the anode effect charge. During the heating of the hearth and the base, when the temperature of the melt in the shaft of the electrolyzer reaches 800-820 C, i.e. the magnitude at which the aluminum refining process is carried out, the electrolyte gradually fills cracks, leaks.

descending into the lower layers of the lining, cool- ing up to the temperature of its crystal lasers and turning into a solid state,

Flooded in luaxTV and a single alloy in

the final stage of the start-up period (12 hours after: o, the spectrometer B and the constant current circuit) displaces the I-upper test zone, the slots x: the electrolyte, ITO is delayed 3 of their lower zone and into the Keplot yus x middle and lower layers until frozen : a rezu - tete blockage of cracks and nepotsennost

tg Erdmi prospoykapch electrolyte metal to the outside of the electrolyzer does not leak

Upon completion of the montage; the linings and heels of the interunit wiring; the fire is heated by the mine with the heat from the combustion of the fillet supplied to the special galg: up to temperature; surface bpocap 300 C and Tei - friepaTvp;, i is a lateral magnesite heat exchanger. After that on the popiiu yKj ia.breaioi IU. sheets, bypass with yours jnoma; T, w

L - STOVNOY coating To obshSY PLOPK,:

podip 0.45 and set G e; f-current cathodes with a gap between the lines of the nil; - nsy rpaiibFo and povauokhnostyo melt mx sheets, equal to mm. Then molten aluminum is flooded (its layer thickness is 12 cm), and the connection is e: (e; st1prt ser B a direct current circuit in the lilevo .i eleustro.chit. Heated cho 8 (} 0 .O

tji, .j L. 5 height c; then which / | 0. It is possible to produce cathodes before the installation of this electrode) :) voltage generator 20 V After 12 hours a cable of an electrolysis cell is a direct current circuit in a plated material of anvoltage, which is starting at the start of the switch; ;-. thiol,

11ri- | The ratio is flat | Maximum Ilpr I

measures spawning the leaflet on e. coatings to the liter P of the launching total area I period at the bottom of the I distance from the lower rpaiiii cathodes to the i

0.08

BUT

2-3 hours after connecting the electrolyzer, 300-400 kg of anode alloy are poured into the DC circuit.

With an increase in the ratio of the area of the sheet covering to the total area of the bottom and the constant distance from the lower surface of the cathode to the bottom, the voltage is not. the electrolyzer during the starting period is monitored; If the interval ratio of the areas is 0.9, then the least stress is achieved compared to the other values (table). However, this does not give any advance to the fissures. In order for the melt temperature to be SOO-SZO C, it is necessary to raise

WWTPI Order 3067/28 Circulation 615

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Random polygons pr-tie, g, Uzhgorod, st. Project, 4

Until the end of the day, it started to lose, with T and the control and the cortex-CTiipoB, the composition of the anodic alloy, which was cooked in the electrolyzer shaft,

0.5 1 .0

15

42

there is

and set the voltage on the electrolyzer not pyzh 15 V.

Thus, the proposed method will eliminate the possibility of anodic alloy penetration into the inner layers of the lining and outside of the electrolyzer, which increases its service life by 4 months.

The use of copper sheets ensures the start-up of the electrodigger without an apod effect, and therefore, without the cost of its elimination.

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Claims (1)

METHOD FOR STARTING AN ELECTROLYZER FOR REFINING ALUMINUM, including heating the bottom and side lining, installing cathodes, pouring cathode aluminum into the shaft and connecting it to a direct current circuit, filling electrolyte and anode alloy, characterized in that, in order to increase service life and reduce costs by elimination of the anode effect, the surface of the hearth is covered with copper sheets before pouring the electrolyte, while the ratio of the area of the sheet coating to the total area of the hearth is 0.1-0.8. Sae 1236005 ²