the solids concentration profile close to the filter cloth – often
referred to as “skin” formation – that causes a low permeability
in this region and hence a high localised pressure loss, and high
cake moisture contents result. Although “skin” formation is a
property of the cake, it results from consolidation of the cake by
constituents of the sludge packing more closely due to a wide
size distribution or deformation of components in the feed. This
results from a high compressive drag force acting on the solids
during filtration, which can have the effect of “pushing” some
of the feed components into the surface of the filter cloth; hence
the cake can have a strong interaction with the filter medium
which, in practical terms, will cause medium blinding.