It is generated during the aluminium smelting process as a result of high Sodium (Na) content in the alumina. Surplus cryolite is liquidly tapped and then crushed to be reused by other smelters or to compensate for electrolyte losses.
We can barite sulfate lumps for both chemical and drilling grades as shown below:
Type A: BaSo4: 92.84 - Specific Gravity: 4.4 (g/cm3)
Type B: BaSo4: 82.99 - Specific Gravity: 4.22 (g/cm3)
Type C: BaSo4: 88.73.84 - Specific Gravity: 4.34 (g/cm3)
Type D: BaSo4: 86.63.84 - Specific Gravity: 4.28 (g/cm3)
Anode butts are the residual electrode left in the electrode holder at the end of electrolysis with prebaked carbon anodes. The anode carbon is being consumed by ohmic resistive heat and electrolytic oxidation. However the part of anode just above the melt is being continuously subjected to high temperature reactions with fluoride melt and atmospheric oxidation, which ultimately results in impurities left in the discarded anode butts.At the end of their use, the left over part of the anode (called butts) are crushed and recycled to produce new anodes. However, while recycling the butts the built-up of sodium concentration is closely checked and controlled in order to avoid harmful effect of excess sodium in newly formed anodes. Good quality anodes should be oxidation resistant in gaseous environment in order to minimize oxidation on the expose surface (C + O2 2CO) [19]
