Filtration example, with centrifugal pump

After the constants have been determined, Eq. (11.7) can be employed to predict filtration performance under a variety of constant rate conditions. For instance, the slurry may be charged with a centrifugal pump with a known characteristic curve of output pressure against flow rate. Such curves often may be represented by parabolic relations, as in Example 11.2, where the data are fitted by an equation of the form... 

In many cases, for example a plate and frame or a leaf press operated with the suspension supplied from a centrifugal pump, the early stages of fdtration are conducted at a nearly constant rate. As the cake becomes thicker and offers more resistance to the flow, the pressure developed by the pump becomes a limiting factor and the filtration proceeds at a nearly constant pressure. For such a combined operation, the plot of Ap against time is as shown in Figure 9.8. The equations are (see equation 9.23)... 

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