Book Synopsis
The anode to cathode distance of a Hall cell is an important parameter to understand and control. If it is excessively large energy is wasted. If it is too small current efficiency is reduced. If smaller yet, the cell will become unstable. The anode to cathode distance is adjusted by moving the anode bridge to control cell resistance.
It is generally assumed in resistance calculations that the bottom of the anodes are in one plane. It is also generally assumed that the cathode surface, which is the liquid metal, is static. Thus the anode to cathode distance is generally assumed to be the distance between the two parallel planes.
In this paper, a simple and accurate method will be described for estimating the anode to cathode distance when the general assumptions noted above are reasonable. In the process of development, measurements and methods will be considered to determine when these assumptions are not valid so as to guard against inappropriate use of the method.