Method and system for forecasting local anode effect in aluminum electrolytic bath

Abstract

The invention discloses a method and system for forecasting the local anode effect in an aluminum electrolytic bath. The method comprises the following steps of 1, obtaining anode currents of anode blocks in the aluminum electrolytic bath at corresponding sampling points in a first time window and a second time window; 2, calculating the average current values of each anode block in the first timewindow and the second time window according to the anode currents of the step 1; 3, calculating the change rate of the average current value of each anode block in the second time window compared with the average current value of the anode block in the second time window; and 4, judging whether the change rate, figured out in the step 3, of each anode block exceeds the forecasting threshold valueor not, if yes, enabling the anode block positions corresponding to the change rates exceeding the forecasting threshold value to be subjected to the local anode effect, and if not, preventing the anode block positions corresponding to the change rates not exceeding the forecasting threshold value from the anode effect. By means of the method, forecasting of the local anode effect in the aluminumelectrolytic bath is achieved efficiently and accurately.

Description

technical field [0001] The invention belongs to the technical field of aluminum electrolysis, and in particular relates to a local anode effect prediction method and system for an aluminum electrolytic cell. Background technique [0002] The anode effect is a conventional process phenomenon in aluminum electrolytic production. It is generally believed that when the concentration of alumina in the industrial aluminum electrolytic cell is lower than a certain value, fluorine-containing ions and oxygen-containing ions are jointly discharged on the carbon anode to form oxyfluorine compound (COF), which then accumulates on the anode surface along with other adsorbed compounds. These substances and gases make the wettability of the electrolyte to the carbon anode worse, making it difficult to discharge, and the effective current density of the anode gradually increases. When the critical current density is reached, the anode effect occurs, the cell voltage increases sharply, and t...

AI Technical Summary

Problems solved by technology

[0006] The signal sampled in the traditional aluminum electrolysis process is only a single current and voltage signal, and the control system will predict the anode effect of the whole tank according to the change of the voltage. It is too late to predict the anode effect, and the effect is basically in the process of continuing, and it is impossible to eliminate the effect in the "infancy" state

In view of the harmfulness of local effects, and the detection of anode effects in traditional technologies is mainly aimed at the whole tank, and cannot detect local anode effects in time, and then eliminate the effects in time, it is necessary to provide a method that can predict local anode effects in aluminum electrolytic cells method

Images