Rheological Improvements in Alumina Industry Clarification Circuits

Abstract

Dewatering and transporting slurries are two common challenges alumina refineries face today. Alumina Refineries are seeing lower available alumina and increased gangue minerals which makes handling of red mud more difficult. While polymers are necessary to achieve faster rates of liquid-solid separation, they can impart negative rheological characteristics, so polymers alone in most cases are not sufficient in the washing of red mud that contains higher gangue minerals and lower available alumina content. Solenis’ rheology modifiers have been successful in bench-top testing, pilot and plant trials at improving rheological characteristics, liquid-solid separation and washing efficiency (savings of caustic and alumina by efficient washing of red mud ) within the counter current decanter circuits of alumina refineries. This paper will cover the efficacy of the rheology modifiers that have been successfully demonstrated from bench-top experiments to full plant trials as a viable solution for rheology modification improvement in the alumina industry.