Clarification

Clarification, the term given to the process by means of which a turbid solution is rendered clear. The simplest mode of clarifying is by filtering the liquid through canvas, etc., or through sand or gravel. In many cases where fine organic matter in suspension is present, the liquid is filtered through animal charcoal, or boiled with this substance, and then filtered, as in sugar refining. Centrifugal machines, depending on the fact that if a liquid be rapidly rotated the suspended matter flies to the side of the vessel, are also sometimes employed. Mordants (q.v.), as alum, may also be used as clarifiers, which, on precipitation, carry down with them the suspended matter.