Cell Geometry Page
The Cell Geometry Page contains essentially the geometric values of the anode table and the cell cavity (see also Cell Geometry Diagrams). AlPrg calculates the masses of the cryolite electrolyte, of the aluminum metal pad, of the side ledge and (if it exists) the mass of bottom sludge.
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Cell Geometry Page. On the Cell Geometry Page you define the dimensions of the anode table and the interior of is electrolytic cell. AlPrg determines the masses of the electrolyte, the aluminum pad, the ledge and the sludge. |
Cell Dimensions
The next figure shows a schematic cross section of an electrolytic cell to explain the meaning of the cell dimension values of the Cell Geometry Page.
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Cell Dimensions. On the Cell Geometry Page you define the dimensions of electrolytic cell like the length, width and height of the cell cavity and of the anode as well as the anode distances from the cell cavity. You enter also the electrolyte and metal pad height, the interpolar distance and values to describe the cell ledge and and bottom sludge. |
Anode Table
You enter the number of anodes and the dimensions (length, width, height) of new anodes.
AlPrg needs the anode final baking temperature to calculate the
Anodic Reaction Overvoltage.
With the length, width and height of the anode butts
AlPrg calculates the Anodic Fanning Factor
and the electrolyte mass.
Masses
AlPrg estimates the masses of the electrolyte, of the aluminum metal pad, of the side ledge and of the bottom
sludge. The program uses the cell cavity dimensions and takes care of an eventual slanted part of the cell sides made of ramming
paste, for instance. The input are average values of the electrolyte, metal pad and sludge height
as well as of the side ledge thickness. AlPrg applies the densities of the electrolyte and metal pad
that is determined on the
Electrolyte Properties Page.
The side ledge is mostly solid cryolite and AlPrg uses consequently its density of ρledge =
2.97 g/cm2.
Addition of excess alumina to the cryolite bath leads to the formation of sludge
that is a suspension of alumina particles in electrolyte saturated with aluminum
oxide (Lit.
Chap. 10.2.2. p. 384). The density of this mixture lies between 2.3 and 2.5 g/cm2. AlPrg uses a value of
ρsludge = 2.40 g/cm2.