On parameters affecting flow behaviour during compressible cake filtration in the centrifugal field

Filter centrifuges show a good dewatering performance compared to pressure filtration. At the same time the compression of the filter cake can be a limiting factor in the use of centrifugal force for filtration, because the compressive force acts directly on the solid particles, thus leading to a higher degree of compression than with pressure filtration only. Experiments have been done with model particles of different particle size to describe the influence of process parameters on filtrate flow. The flow behaviour has been studied in a beaker filter centrifuge which allows hyperbaric centrifugation operation in the same way as the industrial machine types (Heinkel HF-centrifuges). Different analytical techniques have been developed and applied for the characterisation of compressible filter cakes (DMTA, image analysis). Based on the structural information determined analytically, a model has been developed to calculate the deformation behaviour during processing. The model allows the prediction of filtrate flow rate.