Testing and Characterization of Anode Current in Aluminum Reduction Cells

Abstract

Anode current is an important parameter in the aluminum reduction process, but to test the anode current accurately is difficult at present. This study tested the individual anode current using the fiber-optic current sensor. The testing results show that this method can effectively avoid the interference of the electromagnetic field, and the current is measured with high precision which error is less than 1 pct. In the paper, the test currents under different cell conditions, including anode changing, metal tapping, abnormal current, and anode effect, are investigated using the method of time-domain and frequency-domain analysis, and the simulation method is also combined to investigate the cell conditions. The results prove that different cell conditions will show different anode current characteristics, and the individual current can monitor the cell conditions, especially the localized cell conditions. Some abnormal cell conditions can be found through anode current rather than cell voltage. The anode current can also be used for early detection of anode effect.

Analysis of anode current distribution in aluminum electrolysis cell based on equivalent circuit numerical simulation

“…Conn1 and Conn2 are connection ports for connecting external circuits. The remaining nonlinear resistors and equilibrium potential can also be constructed one by one in this way, and the anode-related resistance module can be obtained by connecting them in series [2][3] and packaging them.…”

“…Cheung C Y et al [2] gave a single anode path resistance model, measured and analyzed the current of a newly replaced anode, and divided it into three stages according to the rate of the current uptake. Wang Y et al [3] studied the dynamic simulation of the anode current field equivalent circuit of the reduction cell, established the equivalent circuit model of the anode current distribution, and further studied the variation characteristics of the current field. Yao Y et al [4] presents an approach to estimate in real time the alumina concentration distribution in an aluminum reduction cell based on individual anode current measurements.…”

Research of Magnetic Shielding on the Closing Gap of Optical Fiber Current Sensor

“…In recent years, our team has used OFCSs to measure the electrode currents of aluminum reduction cells [13] and electrolytic troughs of copper [14], the environment of which was very extreme and harsh. Compared with the voltage drop method, real-time electrode current data with much higher accuracy have been obtained, and we determined the current variation characteristics caused by electrolytic cell conditions in metal electrolysis processes.…”