Compressibility, filter cake cell measurements

Compressibility, filter cake, 310, 311,316 cell measurements, 314 calculation example, 314... 

Figure 11.4. Data of compressibilities and porosities of filter cakes, (a) Parameters of the correlation a = a0(hP)n for resistivity of CaSi03 filter cakes at two rates and two concentrations (Rushton and Katsoulas, 1984). (b) Resistivity as a function of pressure measured in a compressibility-permeability (CP) cell [Grace, Chem. Eng. Prog. 49, 303, 367, 427 (1953)]. (c) Porosity as a function of pressure for the same six materials (Grace, loc. tit.).

The cakes obtained from the apparatus in the disc form have 10 mm height and 50 mm diameter. The preparation of the filter cakes from the suspensions having approximately %20 by volume concentration consists of two steps The first step is the application of the filtration and the second step is the compression of the cake for about 20 minutes in the cell. The cakes obtained at these conditions were fully saturated with water. In order to obtain partially saturated cakes, these cakes were dried for a defined time in the open atmosphere in the laboratory. The measurement of the shear strength of these cakes were then made using the apparatus BOS which was designed in the laboratory by ourselves (7). 

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