The fast circular movement of a centrifuge ensures that sludge particles get separated according to their weight. The heavier components get pushed to the outside, while the lighter components migrate inwards.
This technique can be used to make sedimentation processes a lot faster. Another application is dewatering of sludge. When the sludge is pushed against the side of the centrifuge, water migrates to the inside where it is drained.
PCA can help you with this technology, both in design and construction of the installation.