What Pressure- and Cake-Filtration Are All About

This chapter provides a summary of the governing expressions describing conventional pressure-induced filtration and a description of major equipment. Standard filtration practices refers to the most common or classical method of filtration, sometimes referred to as cake filtration. 

The hydrostatic pressure varies from a maximum at the point where suspension enters the cake, to zero where liquid is expelled from the medium consequently, at any point in the cake the two are complementary. That is, the sum of the hydrostatic and compression pressures on the solids always equals the total hydrostatic pressure at the face of the cake. Thus, the compression pressure acting on the solids varies from zero at the face of the cake to a maximum at the filter medium. 

When solid particles undergo separation from the mother suspension, they are captured both on the surface of the filter medium and within the inner pore passages. The penetration of solid particles into the filter medium increases the flow resistance until the filtration cycle can no longer continue at economical throughput rates, at which time the medium itself must either be replaced or thoroughly cleaned. 

At the end of this chapter you will find three annexes. The first of these is a list of nomenclature used in the chapter. There are quite a few design equations that are summarized in the foregoing sections and, hence, you will need to refer to this 

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