COMPRESSION OF DUST CAKES FORMED ON FILTER MEDIA

The rise in pressure drop of periodically regenerable cake-forming surface filters is in many cases not linear but characterized by sudden sharp increases. These jumps result in a higher cleaning frequency, which is disadvantageous for the filtration performance. Local compressions of the dust cake are supposed to be responsible for the jumps. This theory could be confirmed by quantitative analyses of dust cake structures. Locally determined porosities, particle and pore size distributions, and fractal dimensions of three different dust cakes are discussed. Finally a new model is presented, by which the stability and the flow resistance of dust cakes as a function of time can be simulated.