Abstract
A spatially resolved 1-D pressure filtration model was developed for a
slurry of edible fat crystals. The model focuses on the expression step
in which a cake is compressed to force the liquid through a filter
cloth. The model describes the local oil flow in the shrinking cake
modeled as a porous nonlinear elastic medium existing of two phases,
viz. porous aggregates and inter-aggregate liquid. Conservation
equations lead to a set of two differential equations (vs time and vs a
material coordinate ) for two void ratios, which are solved numerically
by exploiting a finite-difference scheme. A simulation with this model
results in a spatially resolved cake composition and in the outflow
velocity, both as a function of time, as well as the final solid fat
contents of the cake. Simulation results for various filtration
conditions are compared with experimental data collected in a
pilot-plant scale filter press.