How can a suspension be separated?
The tiny particles must be coalesced into larger particles that can then be separated by mass and volume.
A suspension is a mixture of solid particles in a liquid. They remain suspended because of their small size and the attractive forces of the liquid molecules.
Separation can only be done if the particle sizes are increased to a size where they will precipitate from the solution. Increasing the gravitational gradient with a centrifuge is also a way to effect the separation.
Usually, a combination of both is used. For many biological samples in a lab, the centrifuge may be sufficient directly. For industrial process centrifugation is not possible, and coalescence is the only practical method. This can be effected or enhanced with chemicals called "flocculants".