Alcoa STARprobe™

Abstract

Alcoa STARprobe™ is a probe device/system used to measure cryolitic bath properties including Superheat, Temperature, Alumina concentration, and cryolite Ratio (acidity), STAR, all together in real time for active pot control. The proprietary measurement principle is based on differential thermal analysis (DTA). This paper shows the fundamentals of operation along with the correlation of all the analysis with the accepted methods of XRD and pyrotitration for acidity, thermocouples for Bath Temperature and LECO and XRF analysis for alumina. The timing of the measurement will be shown to be equal to the traditional methods and the reliability (including reusable use of the probes) will also be described.