Compressible cake characterization from steady-state filtration analysis

A numerical technique for quantifying the key material properties that describe how a flocculated suspension behaves under constant pressure filtration is presented with unrestricted compressive yield stress and permeability models used to describe these material properties. Using an iterative procedure, the optimal parameters for these models are calculated as are pressure and solid fraction distribution profiles. Input parameters to the numerical analysis are flux and final cake height data obtained from batch filtration experiments, which are driven to steady-state. This technique is validated against piston driven filtration (odeometer) and centrifuge experiments for zirconia, soil particles, and yeast assemblages. The compressive yield stress calculated from filtration experiments agrees well with values obtained by odeometer and centrifuge studies for all particle systems studied at both the low and high solid pressure regions. Similarly, the calculated permeability agrees well with the measured permeability. (c) 2007 American Institute of Chemical Engineers