Food Colloids

Abstract

Definition Flocculation is a process whereby small particles in suspension are caused to aggregate, giving large clusters (flocs) that are much more easily separated than the original particles. The process is in widespread use in many industrial applications. Overview Flocculation is a process that is widely used in industrial applications, such as biotechnology, mineral processing, papermaking, water and wastewater treatment, and others. It depends essentially on collision and attachment of particles in a suspension. In this way, particle aggregates (flocs) are formed that are very much larger than the original (primary) particles so that they can be more easily separated by physical methods. The generic term for this process is "aggregation," but the terms "coagulation" and "flocculation" are also widely used, often with distinctly different meaning. In this entry, "flocculation" will be used predominantly, and the question of terminology will be addressed briefly in the final section. Since almost all practical applications of flocculation are for water-based systems, the discussion here is confined to aqueous suspensions.