TABLE OF CONTENTS The calculations presented in Sections 6.4.1 and 6.4.2 illustrate the degree to which the operation of a filter can be predicted from the knowledge of suspension and cake properties as well as basic operational parameters. Simulations develop these procedures to allow the performance of batch filters to be investigated over a wide range of process conditions without the need to perform costly sequences of experiments. While any of the filters shown in Table 6.1 can be simulated with the aid of the equations and procedures presented throughout this chapter, the diaphragm filter press cycle considered in Section 6.4.1 is chosen to illustrate the process.
To aid the simulation process, the Filter Design Software described in Chapter 5 has been used to investigate the effects of changing formed cake thickness on filter performance. There are several ways to consider this problem, two of which are highlighted below. In Section 6.5.1, the mass of solids in the feed that enters the press is maintained at a constant value (i.e. 4527 kg) and the cake thickness per filtering surface is varied over the range 10 40 mm. The consequence is a changed filter area to compensate for the different cake thickness. In Section 6.5.2 a different approach is taken whereby the formed cake thickness is altered over the same range but this time the filter area is fixed (i.e. 300 m 2) such that the mass of solids varies.
