| Abstract Scope |
Computer control of aluminum reduction cells started in the early 1960s, first for voltage control by anode beam movement. Next came alumina feeding control by cell resistance monitoring. Invention of point breaking/feeding in prebake cells, combined with continuous overfeeding and underfeeding of alumina, invented in the 1970s, brought alumina concentration to 2-3%, an optimum for cell performance until today. Bath chemistry also became computer controlled by automatic feeding of AlF3. From these fundamentals, as the computer speed and capacity increased, the computer control became more sophisticated and intelligent in reaction to alumina quality, cell conditions and cell operation routines, with the aim to achieve constant target parameters in every cell of a potline. Prediction and practical elimination of anode effects reduced PFC emissions to minimum, for cleaner environment. In this paper we trace the computer control from the beginnings to the most recent applications of artificial intelligence and Industry 4.0. |