Modeling of the Consolidation Stage in Pressure Filtration of Compressible Cakes

Whither compressional rheology?

“…Thus, it is difficult to get the slope and ∞ values from a single pressure run, and stepped pressure runs are not useful. A recent advance that has proven practical for such systems is that the material properties can be deduced from the compression stage of filtration [31][32][33]. Since the asymptotic behaviour is logarithmic to first order, ∞ and D( ∞ ) are given by fitting a logarithm to experimental filtration results [33].…”

Effect of ionic strength and pH on hydraulic properties and structure of accumulating solid assemblages during microfiltration of montmorillonite suspensions

“…While this approach is generally acknowledged to assist in prolonging the operational period of a membrane before cake removal is required, a lack of knowledge of the structure of the filtration cake formed from aggregation of contaminant particles and uncertainty with regard to how the hydraulic properties of the cake might change on increase in applied pressure has limited our ability to optimise the coagulation-filtration process [38]. This lack of knowledge is due to the complexity of the filtration process which, despite its apparent conceptual simplicity, lies at the intersection of particle network theory and the underlying colloid and interface science, suspension rheology, hindered settling, and transport phenomena [39]. Clearly, the key to achieving optimal coagulation is the knowledge of both (i) the structure of assemblages of particle induced to associate as a result of both the water composition and the filtration process and (ii) the bulk properties of the resulting cake layer.…”

Parameter estimation and simulation of dependence of constant pressure batch dewatering on initial solids concentration

“…Detailed derivation of the dewatering model has been presented earlier and hence is only briefly outlined here (Kapur et al, 2002;Raha et al, 2006). The model is formulated by assuming that dewatering is completed in two distinct stages (Fig.…”

“…It is frequently assumed that dewatering occurs in two stages (Shirato et al, 1970;Landman and White, 1997). This feature can be clearly seen in several sets of published experimental data (Wakeman et al, 1991;Sis and Chander, 2000;de Kretser et al, 2001;Kapur et al, 2002;Brown and Zukoski, 2003;Raha et al, 2006). The progress of dewatering is commonly depicted by the temporal evolution of the cumulative volume of filtrate, V, or the instantaneous average solids volume fraction, ϕ, etc.. A typical two-stage dewatering curve in t-ϕ coordinates is shown in Fig.…”