3. Filtration

Filtration is designed for particle suspensions which, even at low concentration, constitute complex systems. These suspensions may contain a large number of species (mineral microparticles, micro-organisms, yeasts, bacteria, cells and cell debris) and macromolecules. The liquid that has undergone filtration is called filtrate, and the filter retains a residue called retentate, or sometimes cake. The term filtration covers a wide range of techniques, classified according to :

• particle size and pore size of filter media ;

• filtration system configuration (sample circulation mode) ;

• the force involved (vacuum filtration or pressure filtration) in filtration systems