Sedimentation Kaolin Polyacrylamides

The influence of interactions between hydrolyzed aluminum ions and polyacrylamides on the sedimentation of kaolin suspensions Roberts, Kelvin; Kowalewska, Janina; Friberg, Stig; Abstract. Publication: Journal of Colloid and Interface Science.

Flocculation and dewatering of the Kaolin slurry treated by single- and dual-polymer flocculants ... flocculants. The influence of the flocculant type and dosage, under single- and dual-dose conditions, on slurry's sedimentation and the filtration characteristics, were thoroughly discussed. ... nonionic polyacrylamides (NPAMs) with the ...

The critical velocity of sedimentation of kaolinite clays is in the 26 to 28 cm/s flow velocity range (0.22 to 0.25 Pa), appears insensitive to a wide range of suspended sediment concentrations and salinities, and coincides …

Methodologies include sedimentation tests (low solids content), viscosity. concentrations, molecular weight and ionic types of polyacrylamide. Fabric development is. verified using scanning electron microscopy (SEM). Fabric changes in sedimentation, viscosity, type of …

The kaolin used in this study was an untreated kaolin from Wilkinson Kaolin Associates LLC (Gordon, Georgia). The chemical composition (Table 1) is approximately that of pure kaolinite as defined by Murray (1991) with a small content of impurities.The kaolin was converted to a monoionic sodium kaolin using a conversion method modified after van Olphen …

Request PDF | Polyacrylamides Revisited: Flocculation of Kaolin Suspensions and Mature Fine Tailings | A series of acrylamide-based water-soluble (co)polymers was synthesized and they were ...

Based on 2D fractal dimension, the effect of aluminum ion (Al³⁺) on kaolinite flocculation using anionic polyacrylamides (APAMs) as flocculant has been investigated at pH 4.

The influence of cationic and anionic polyacrylamides (PAM) on the floc size, ... particles into larger particles is common practice in order to effect an efficient solid–liquid separation by gravity sedimentation. When these submicron-sized particles are aggregated either by polymer-induced flocculation or by salt-induced coagulation, the ...

Effects of surface charge and shear during orthokinetic flocculation on the adsorption and sedimentation of kaolin suspensions in polyelectrolyte solutions

This type of behaviour is observed by Pearse and Barnett [9] who carried out filtration experiments using kaolin flocculated with different polyacrylamides. These authors report that the mechanically strong flocs produced by cationic polymers are much more effective in filtration than the weakly structured flocs resulting from the use of ...

The adsorption of PAM-A on kaolin is governed by a combination of both physisorption and chemisorption.The optimum flocculation concentration of PAM-A for fresh kaolin as well as surfactant-pretreated kaolin corresponds to about 50% coverage of the surface (i.e. Γ opt. floc ≈Γ ∞ /2). Pretreatment of kaolin with all three surfactants form bigger flocs with PAM-A.

to understand fabric development in kaolin–polyacrylamide systems by investigating the impact of charge type and chain length of poly-acrylamide on the behavior of kaolin over a wide range of solids contents and strain conditions. Sedimentation tests (low solids con-tent, zero strain condition), viscosity measurements (intermediate

On the other hand, non-ionic polyacrylamide flocculant, which is predominantly chemisorbed on kaolin and exhibits a more stretched conformation, is most suitable for enhancing sedimentation rate.

Semantic Scholar extracted view of "The effect of colloid concentration and pH on kaolin suspensions flocculated with cationic polyacrylamides of high molar mass" by R. Gill et al. ... The impact of desilication products on the flocculation and sedimentation properties of bauxite residue. A. Senaputra. Environmental Science, Materials Science ...

ABSTRACT Suspensions of negatively charged kaolin clay as a model system have been flocculated by adsorbing nonionic, cationic, and anionic polyelectrolytes under shear. Test results show that the maximum rate of settling increases with charge density of the cationic polymer being used. Both cylinder test and jar test using low shear conditions tend to underestimate …

Differently from the removal efficiency of water turbidity after sedimentation, ... kaolin (Al 2 Si 2 O 5 (OH) 4 /H 2 Al 2 Si 2 O 8 ·H 2 O; chemical grade; formula weight, 258.16; Shanghai, ... In the present study, the role of cationic, anionic and nonionic polyacrylamides (PAMs) in ballasted flocculation of clay suspensions was comparatively ...

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The sedimentation rate decreased with the increase in flocculation time for all coarse quartz-based tailings conditions (Figure 4 C,D). However, for fine quartz-based tailings, the trend is only clear for tailings of Qz:Kao = 9:1. For tailings with higher kaolin contents, the sedimentation rate tends to be constant with flocculation time.

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The effects of the surface charge and molecular weight of anionic and cationic polyacrylamide (PAM) on the surface chemistry, settling rates, floc sizes and sediment bed compactness of kaolinite suspensions has been investigated at pH 7. At optimum polymer concentrations, the kaolinite floc sizes were larger and the settling rates greater in the …

Flocculation properties (settling rate, sediment thickness, supernatant clarity) of Na- and Ca-kaolinite suspension have been studied in the presence of cationic polyethyleneimine …

Despite theoretical charge-related APAM-kaolin repulsion, APAM has been suggested to flocculate kaolin more efficiently than cationic polyacrylamides (Nasser and James, 2006). According to Stokes Law, sinking velocities decrease with …

The effects of calcium and aluminum ions on the interaction behavior of anionic polyacrylamide (anionic PAM or HPAM) and kaolin are important in determining the efficient flocculation of kaolin. While kaolin surfaces are negatively charged in media such as water, they exhibit the positive surface charge characteristic at pH below 3.2 in the solution of calcium …

Colloidal behavior of kaolinite particles in water was investigated in this manuscript, without and with the addition of a polymer flocculant (non-anionic polyacrylamide (PAM)), using diverse …

Standard kaolin suspensions were flocculated with four cationic polyacrylamides of varying molar mass but the same cationic charge density. Floc size measurements at pH 5.0 were carried out using the Malvern 3600-D particle sizer. ... The flocculant performance was characterised by measuring the sedimentation behaviour as well as the residual ...

Differently from the removal efficiency of water turbidity after sedimentation, ... kaolin (Al 2 Si 2 O 5 (OH) ... In the present study, the role of cationic, anionic and nonionic polyacrylamides (PAMs) in ballasted flocculation of clay suspensions was comparatively evaluated at three representative dosages of aluminum sulfate (AS) coagulant ...

The sedimentation performance of kaolin particles under non-stirring conditions in the absence or presence of KLD were assessed by a vertical scan analyzer, Turbiscan (Lab Expert, Formulaction).

Cationic polyacrylamides of varying molar masses but of similar charge density were tested as flocculants for kaolin suspensions. Flocculant performance was assessed by determining the extent of polymer adsorption, the subsidence rates of the flocculated suspensions and the residual turbidities of the resulting supernatants.

This modifies the sedimentation properties of the mineral slurry. Thus classical measures of flocculation, among them the settled bed height and the supernatant turbidity, have tended to …

Download Table | Characteristics of polymers used for the sedimentation experiments from publication: Comparative Study of Branched and Linear Polymers for the Regulation of Clay Dispersion ...