Blog: Improve thickener operations by measuring density 3/3

Posted on Friday, 7 February 2020 at 01:02

In the last weeks, we described the importance of water recovery and the investments that help to improve the recovery of valuable minerals. This week, we will focus on the efficient use of flocculants.

Flocculants are chemicals by which fine particles are caused to clump together into a floc. These flocs of particles weight more than one fine particle itself, therefore the effect of gravitational forces is increased, and so is the sedimentation rate.

Inefficient use of flocculants leads to extra reagent costs and a less effective operation. Therefore, the operator sets a target density in the feed of the thickener. Process operators want to target the highest solids percentage by weight of the feed slurry at which free settling of particles can occur in the thickener.

Measuring the density of feed slurry in the thickener is important for process control, to improve flocculant use and efficient control of the mixing process. The feed slurry is monitored in real-time by an in-line density meter to “see” if the density value complies with the target density.