Situation

The commercial value of bauxite deposits and bauxite shipments is determined by the amount of alumina that can be extracted under Bayer plant conditions.

Problem

Methods used for alumina extraction often consist of open flames, hot oil baths or air convection ovens, which are often dangerous, inefficient or very expensive.

Solution

Alcan has developed a safe, reliable, cost‑effective alumina extractor to simulate alumina extraction in the laboratory: the ALExx.  This high performance tumbling digester is used for pressurized caustic extraction of alumina minerals.  It is able to accept up to sixteen ml Parr pressure vessels containing caustic and bauxite slurries.  ALExx can be successfully used in other caustic extraction applications, such as the pulp and paper industry with its black and Kraft liquors, or in any mineral process where caustic extraction is required.

Advantages

• Constant tumbling action and numerous heating elements, which makes the process safe and efficient.
• Temperature control.
• Precise digestion temperature, agitation and duration.
• Caustic extraction of bauxites, red muds and a variety of other minerals.