Red Mud (digested bauxite residue) is the industrial waste generated by aluminium refineries using the Bayer process to transform bauxite ore into alumina. The red colour is due to the presence of iron oxides (along with other oxides). For every tonne of Alumina produced, approximately 1-1.5 tonnes of Red Mud is obtained. The high production volumes and high alkalinity of this waste pose a significant environmental, safety and storage problem. Initially the red mud was sent to lagoons which, over the years, have proved to be a danger to the surrounding areas (possible flooding and destruction).
Diemme Filtration technology in the treatment of Red Mud
Diemme® Filtration has been among the pioneers in the industry to develop know-how in this field, working with numerous refineries in various parts of the world.
The plants that have adopted this choice have obtained these main results:
- A more compact waste that is easier to transport.
- Footprint savings compared to wet storage.
- Elimination of flooding risks.
- Recovery of soda ash to be reused in the plant.
Over time, Diemme® Filtration has become the designated partner of several large groups in the industry, developing specific product lines for each of these players and for the treatment of industrial sludge.
The choice of materials able to cope with typical temperatures and pH for this application and the measures taken to increase the flexibility of the equipment have allowed Diemme® Filtration to be recognised as a leader in this field.
The Client is a big Group having one of the most important Alumina Refineries in North America using the Bayer Process by leaching the bauxite ore with caustic soda. The generated waste is a slurry called “Red Mud”. The Red Mud, containing caustic soda, was…