Cake structure

Compressibility, permeability Temperature Effect of mechanical forces on cake structure (e.g, shearing or axial loading)... 

The structure of the cake formed and, consequently, its resistance to liquid flow depends on the properties of the solid particles and the liquid phase suspension, as well as on the conditions of filtration. Cake structure is first established by hydrodynamic factors (cake porosity, mean particle size, size distribution, and particle specific surface area and sphericity). It is also strongly influenced by some factors that can conditionally be denoted as physicochemical. These factors are ... 

Due to the combining effects of hydrodynamic and physicochemical factors, the study of cake structure and resistance is extremely complex, and any mathematical description based on theoretical considerations is at best only descriptive. 

When the cake structure is composed of particles that are readily deformed or become rearranged under pressure, the resulting cake is characterized as being compressible. Those that are not readily deformed are referred to as sem-compressible, and those that deform only slightly are considered incompressible. Porosity (defined as the ratio of pore volume to the volume of cake) does not decrease with increasing pressure drop. The porosity of a compressible cake decreases under pressure, and its hydraulic resistance to the flow of the liquid phase increases with an increase in the pressure differential across the filter media. 

Konstandopoulos, A. G., and Kladopoulou, E. The optimum cell density for wall-flow monolithic filters Effects of filter permeability, soot cake structure and ash loading. SAE Technical Paper No. 2004-01-1133 (2004). 

A decrease in total volume or localized loss of structure can also be associated with a condition referred to as collapse [30]. This condition occurs when the frozen or partially dried material exceeds the phase transition at which the material may again become fluid. Samples of dried product in Figure 4 illustrate the appearance of the cake structure caused by extensive collapse. 

K, is mainly determined by the filter cake structure thus closely related to the physical properties of the dust itself. 

Schmidt, E, Loefller, F. (1991) Analysis of dust cake structures. 

Press type Cake % solids Cake structure Cake thickness (mm) Cake compr. strength (tpf) Average rate (pph/ft2)... 

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