3.1. Flux decline behaviors of mixed suspension
Typical data of constant pressure filtration experiments conducted using binary particulate mixtures are plotted in Fig. 3 as the form of the reciprocal filtration rate (dθ/dv) against the cumulative filtrate volume v per unit membrane area, where θ is the filtration time. In the figure, p is the applied filtration pressure, dm is the nominal pore size of the membrane, dp is the particle diameter, s is the mass fraction of solids in suspension, and the subscripts 1 and 2 stand for the first (larger) and the second (smaller) particles components, respectively. The results for each single component are also included in the figure. It should be noted that the term (dθ/dv) is a measure of the total filtration resistance Rt to the filtrate flow and is expressed by the Darcy’s law in the form:
equation(1)
where μ is the viscosity of the filtrate