Abstract
To obtain accurate values of filtration characteristics as the ratio m of wet to dry cake mass and the average specific filtration resistance αav, constant-pressure filtration experiments were conducted using a filter having a hole at the top of the filter chamber. The relation between the cake thickness L and the filtrate volume v per unit medium area, which serves as a basis of the determination of m and αav, can be obtained on the basis of the principle of sudden reduction in the filtration area of the cake surface. The constant-pressure filtration characteristics obtained by this method were fairly consistent with the estimated values based on compression-permeability cell data. The values of m and αav are influenced by filtration pressure and by slurry concentration. However, these values remain constant during any one constant-pressure filtration experiment. On the basis of the constant-pressure filtration data obtained by this method under various pressure conditions, the local porosity ε and the local specific filtration resistance α can be determined approximately.
