DETERMINATION OF THE CRITICAL PRESSURE DROP FOR FILTRATION OF SUPER-COMPACTIBLE CAKES

Solid-liquid separation of floculated biosolids or sewage sludge led to the formation of super-compactible cakes. For these them, as pressure increases, a critical region is reached where the flow rate does not respond to the increase of the overall pressure drop. In this paper, the fundamental laws of flow through porous cake are used to explain the strange behaviour of of super-compactible materials, and a simple stepped pressure filtration experiment for measuring compactibility parameters is presented.