Cascade Feeding System at Alma

Fives Alumina Feeding Cascade Aluminium -FIVES

Fives has successfully put in operation its innovative Cascade Feeding System on three Gas Treatment Centers (GTCs) at the Rio Tinto‘s Alma smelter, located in Quebec, Canada.

This system has been implemented as part of the global AP30 Pot Amperage Increase Program, boosting pot amperage to 400 kA, while respecting the HF emission limits allowed by the existing permit.
The integration of the Cascade system has occurred smoothly despite all three GTCs were operating 24 hours a day without interruption; it was a key factor synchronizing the installation process with the sequence of annual maintenance.

The Cascade Feeding System is a patented invention from Fives. It consists of an innovative redistribution of fresh alumina within the GTC, that enhances the capture of HF pollutants at higher pot gas temperature.
This is a premiere retrofit implemented on the TGT–RI filtering technology, confirming the successful results already obtained on the last generation of filters, Ozeos, installed at the Rio Tinto’s Jonquiere plant.
The Cascade Feeding System is a simple solution for modifying and improving the performance of GTCs. Test results have shown a 35% improvement of HF capture on the TGT-RI while operating under the Cascade mode with hot gas temperature.