SU1093255A3 - Method for obtaining symmetricity of vertical component of magnetic field in electrolytic cells for aluminium production - Google Patents

Abstract

Under each head of the cells, a balance loop is arranged providing an additional vertical magnetic field, substantially equal to the mean vertical magnetic field of the cell on the small side thereof, and in opposite direction, and at least a fraction of the current which travels through the upstream negative collector is passed in each of these loops. Application to series of high intensity, igneous electrolysis cells, for the production of aluminium.

Description

WITH

11 The invention relates to the production of aluminum by the method of electrolysis of molten cryolite salts, mainly in electrolytic cells with their transverse arrangement in the body of electrolysis. A known method for compensating a magnet field in a series of longitudinally located baths, by increasing the cross section, and therefore, and the current in the bypass package of cathode tires located on the side of the adjacent row of electrolyzers, as compared with the second bypass package of cathode tires 1. The disadvantage of this method is the incomplete compensation of vertical field coupling field 82. The closest to the proposed method is that according to which the bottom of the electrolyzer parallel to the end of the cathode casing is most distant from the adjacent row of electrolyzers located transversely in the PLANE constituting the end face angle the anode surface, an additional compensating cathode bus is laid, forming a closed loop L2D with the side cathode bus. The disadvantage of this technical solution is a higher level B floor; at the end, located closer to the adjacent row of electrolyzers. The aim of the invention is to increase the aluminum output by current by compensating for the vertical component field. This goal is achieved by the fact that according to the method of ensuring the symmetry of the vertical component of the magnetic field in electrolyzers to produce aluminum, located transversely to the axis of the series, including the creation of a correcting magnetic field by a closed loop formed by a side cathode bus and a tire passing under the bottom of the cathode casing, closed the contours are located at each of the two ends of the cathode casing, the currents in them are defined by the ratio I 0.707 hB, where I is the current in the circuit, kA; h is the vertical distance between the working surface of the anode and the tire passing under the bottom of the casing in meters; 5 V is the vertical component of the induction of a corrective magnetic field, Gs. The drawing shows the layout of the anode and cathode tires of two transverse electrolyzers, indicating the location of the circuits. The electrolyzers 1 and 2, located transversely with respect to the axis of the series 3, have a cathode busbar symmetrical with respect to this axis, formed by cathode tires 4, 5, and 6.7 and lateral cathode tires 8.9 and tires 10 and 11, passing under the bottom of the cathode housing of the electrolyzer, form a circuit I- located closer, and a circuit with a current Ig located farther from the adjacent row of cells. The currents in the circuits are determined after measuring the magnetic field in the corners of the anode circuit. The measurements take into account the uncompensated field B generated by the currents of the adjacent row of electrolyzers and the field of magnetized steel structures. The currents in the circuits are then determined from formula I 0.707 h B,. where I is the current in circuit i or e; h is the distance from the working surface of the anode to the axis of the tire passing under the bottom of the cathode shell. I. create a floor that compensates for unbalanced vertical induction components, primarily in the corners of the bath with molten aluminum. For example, the day of a series of transverse electrolyzers operating with a load of 90 kA, with a distance between rows of 14 m induction at the points indicated in drawing B, B2, B-j and DB, measured by compensation with and without it, is shown in the table. Calculated by formula currents I.. 9 kA and 1 22.5 kA provide a more symmetrical distribution of the vertical component of the magnetic induction.

Claims (1)

METHOD FOR ENSURING VERTICAL COMPONENTS OF THE VERTICAL MAGNETIC FIELD IN ELECTROLYZERS FOR PRODUCING ALUMINUM, located transversely to the axis of the series, including creating a correcting magnetic field with a closed loop current formed by a side cathode bus and a busbar passing under the bottom, which has a lower cathode that current, closed circuits are located at each of the two ends of the cathode casing, passing in them currents determined by the ratio I = 0.707hB _z , where 3 is the current in the circuit, kA; ι h is the vertical distance between the working surface of the anode and the tire passing under the bottom g of the casing, m; the vertical component of the induction of the correcting magnetic field of the circuit, G. >