What is the difference between Siltation and Sedimentation?

The difference between siltation and sedimentation is that "siltation" is the increase in concentration and or of deposition of water-borne silt in a body of water and "sedimentation" is the separation of a suspension of solid particles into a concentrated slurry and a supernatant liquid, either to concentrate the solid or to clarify the liquid.

What is the difference between Elutriation and Sedimentation?

The difference between elutriation and sedimentation is that "elutriation" is the process of separating the lighter particles from the heavier ones by means of an upward directed stream of gas or liquid and "sedimentation" is the separation of a suspension of solid particles into a concentrated slurry and a supernatant liquid, either to concentrate the solid or to clarify the liquid.