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Advances in Filtration and Separation Technology

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Cake filters, Filters and filtration -- Mathematical models, Pore water -- Analysis, Porosity -- Measurement, Water -- Purification -- Filtration


During the initial stages of a Buchner funnel or specific resistance test, gravity drainage occurs prior to application of the pressure differential. Some allow time for a small cake to form by gravity drainage. Filtrate data from the gravity drainage period can be used to determine constitutive properties of the cake under a hydrostatic pressure gradient. The constitutive properties that define the structure of the cake include the permeability and porosity as functions of the applied stress. Equations governing the drainage rate during a gravity filtration experiment assuming a constant and a non-constant average cake permeability and cake porosity were developed. Numerical solutions were shown predicting the gravity drainage rate given known constitutive relationships. Also, a procedure was shown illustrating how constitutive relationships could be determined using gravity drainage data.


This is the author's version of an article subsequently published in Advances in Filtration and Separation Technology, vol. 12 (1998): 646-653.

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