An interesting effect is observed when studying the filtration or permeatio
n of a fluid through a cake of a compressive material, such as chemical slu
dge, at low hydraulic pressures. It has been tested that the specific flow
resistance depends on the effective solids pressure and also on the flowrat
e or on the solids mass of cake/cross area ratio. A mathematical model has
been developed to explain the experimental results obtained at different pr
essure losses, distinct temperatures and cakes formed in different ways. (C
) 2001 Elsevier Science S.A. All rights reserved.