Improvement of Fluorinated Products Consumption in an Electrolysis Series for Primary Aluminum

The problem solved in this paper concerns the improvement of the consumption of fluorinated products in an electrolysis series for the production of primary aluminum. It will be a question of reducing the specific consumption of aluminum fluoride (AlF3) and of stabilizing the average excess rate to a reasonable threshold; to improve AlF3 tank feeding techniques in terms of QHSE (Quality Health Safety Environment). To achieve this goal, the adopted methodology begins with the use of the DMAAC approach associated with the Lean manufacturing tools, which will limit the waste of aluminum fluoride in the primary aluminum manufacturing process. After deploying this tool, we implemented operational solutions to limit the causes of overconsumption, designed and implemented a new correction scale and improved operational best practices. This allowed us to see the specific consumption of aluminum fluoride decreased from 40 kg to less than 30 kg per ton of aluminum produced, while maintaining the rate of excess of AlF3 between 8.5 and 9.5 %.