Pressure filtration of dispersed and flocculated alumina slurries

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

“…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.…”

Pareto Profile Benchmark for Kinetics of Filtration and Extent of Dewatering of Fine and Colloidal Suspensions

“…Pressure filtration, the focus of this work, is employed routinely for dewatering of fine and colloidal suspensions, which give rise to compressible filter cakes. This process has been studied experimentally and modeled theoretically by many investigators. − In many instances, the theoretical treatment seeks to couple material-independent solid−liquid continuity−momentum balance equation with material-specific constitutive relationships. The latter describe the characteristic rheological properties of the suspension that are relevant to dewatering, namely, cake compressibility and specific cake resistance.…”

“…The performance of the filtration process can be altered greatly by manipulating one or more physical-chemical variables and parameters such as applied pressure, solid concentration, slurry preparation method, suspension pH, additives such as surfactants and polymers and their dosage, etc. A number of studies exist on the effect of pH and additives on the state of aggregation in a suspension and its filtration behavior. ,,− Appropriate manipulation of the suspension chemistry usually leads to either faster filtration rate or higher moisture removal and any improvement in one measure invariably results in deterioration in the other. ,,, …”

“…This process has been studied experimentally and modeled theoretically by many investigators. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] In many instances, the theoretical treatment seeks to couple material-independent solid-liquid continuity-momentum balance equation with materialspecific constitutive relationships. The latter describe the characteristic rheological properties of the suspension that are relevant to dewatering, namely, cake compressibility and specific cake resistance.…”

A Mean Phi Model for Pressure Filtration of Fine and Colloidal Suspensions

“…These stages are invariably encountered in compressible filter cakes that are formed when fine and colloidal suspensions are filtered. The compressibility of filter cake is accounted for by simple expedient of making α v and φ _ functions of the applied pressure, for example, power functions of ∆P (Holdich, 1993;Tiller et al, 1995;Tiller and Kwon, 1998;Sis and Chander, 2000). Other researchers (Stamatakis and Tien, 1991;Chase and Wills, 1992;Lu and Hwang, 1993;Holdich, 1993;Tien and Bai, 2003;Bai and Tien, 2005) have made use of solid/fluid continuity-momentum balance equations with appropriate constitutive relationships for porosity variation along the cake thickness.…”