Cracking behavior of compressible filter cakes

In cake filtration, shrinkage cracking is an undesirable phenomenon as it leads to deterioration of the filtration process in terms of residual moisture, gas consumption and overall cost. Whereas shrinkage cracking has been extensively studied for thermal drying, there is little research on shrinkage and cracking behavior in a filtration process. Aim of this work is to investigate the relationship of dewatering, shrinkage and crack onset and propagation for compressible filter cakes during vacuum filtration. We combine an image analysis technique with laser displacement measurements to investigate in-plane and vertical shrinkage during cake dewatering. The influence of the boundary on cracking behavior and the saturation at crack onset are determined. The influence of filtration pressure on crack area and crack propagation speed will be discussed.