Thickeners or gravity sedimentation is the most widely applied dewatering technique used in mineral processing.^[1] Thickeners separate minerals based on their settling velocities. They comprise of relatively shallow tanks where the clear liquid on top is the overflow, and the underflow is the sludge slurry found at the bottom of the tank.

[edit] References

1. ^ Wills, B.A. Mineral Processing Technology. 7th ed. Oxford, UK: Elsevier, 2006. Print.

Inclined rakes are also used to increase the settling rate of the particles.Thickened pulp is either pumped to tailing disposal or,if containing values,pumped direct to the concentration process.