Analysis of floc morphology in a continuous-flow …
The floc morphology was investigated in a continuous-flow reactor, in order to understand the evolution of flocs in practical flocculation and sedimentation processes in water utilities. Kaolin-humic acid suspension was used as the test water, and polyaluminum chloride was chosen as the coagulant.
Effect of hydrodynamic breakage on floc evolution and …
Flocculation and sedimentation have been widely used to remove colloids and particles from water as part of the drinking water treatment process (Huang et al. 2016).In the flocculation process, with the addition of flocculants into the suspension, unstable particles form due to the charge neutralization mechanism and aggregate into flocs by adsorption bridging …
Clay-bacteria interaction: Effect of bacterial cell density on
These observations from the abiotic kaolin sedimentation tests are well consistent with previous study results reported by Palomino and Santamarina (2005). ... It is worth pointing out that kaolinite clay particles form macro-flocs and show a solid-like sedimentation behavior at pH greater than the IEP of the kaolinite edge (pH 9.1).
Particle-size characterization of flocs and sedimentation …
The final solids content of kaolin was approximately constant regardless of salt type and concentration (solids content = 26–37%). Soda ash mine tailings exhibited sedimentation behavior similar to kaolin, which showed approximately constant initial sedimentation rate and final solids content for the range of salt concentrations evaluated.
Characterization of kaolin flocs formed by polyacrylamide as
Semantic Scholar extracted view of "Characterization of kaolin flocs formed by polyacrylamide as flocculation aids" by Zhe Zhu et al. ... The sedimentation studies revealed that KLD5 was very effective in flocculating kaolin particles, and the adsorption, zeta potential and flocculation results confirmed that the polymer with the highest charge ...
Effects of polyethylenimine dosages and molecular weights …
A high PEI dosage of 0.4 dwb% was chosen primarily to display possible PEI dosage effects on the sedimentation of kaolin slurries. PEI Mw were varied between low Mw of 1800 ... At 10 min into sedimentation, settling rates of flocs formed with 0.4 ...
Comparison of novel magnetic polyaluminum chlorides …
However, when seeding magnetic nanoparticles directly into the target water (Fig. 8 (b)), the traditional PACl-kaolin-HA flocs were apt to form. A part of magnetic nanoparticles would be wrapped into those flocs by particle collision and PACl coagulation. ... In that case, MSC-flocs would have lower sedimentation efficiency than MC-flocs ...
Effects of humic acid on physical and hydrodynamic properties of kaolin
The physical and hydrodynamic properties of kaolin flocs including floc size, strength, regrowth, fractal structure and settling velocity were investigated by in situ particle image velocimetry technique at different humic acid concentration. Jar-test experimental results showed that the adsorbed hu …
Influence of Kaolin on the Formation and Sedimentation of …
Sd-shaped). After that, the flocs would collide and combine with each other and form larger OcPAs (Dd- and Md-shaped), whereas the void fraction between the flocs is filled with kaolin. The specific composition and structure of OcPAs change their settlement rules a lot compared to the flocs in water treatment system.
Flocculation and dewatering of the Kaolin slurry treated by …
To mitigate the sudden increase in the production of waste engineering slurry, predominantly composed of Kaolinite, this study investigated the flocculation and dewatering of …
Floc size estimation in iron induced electrocoagulation and …
The present work deals with the estimation of average floc diameter using sedimentation and optical data. This study was applied to a kaolin suspension destabilized by chemical dosing with iron salts (FeCl 3 or FeSO 4) or electrocoagulation (EC) with iron electrodes.Optimum pH and coagulant concentration were defined by turbidity measures on …
Recycling Polystyrene Plastic Waste: A Sustainable Solution …
3.1 Characterization 3.1.1 Infra-Red Spectroscopy (FTIR). Figure 2 displays the FTIR spectra of flocs, kaolin particles, and PSS. The peaks at 800 cm −1 and 1097 cm −1 were attributed to Si–O and Si–O-Si, respectively. The findings indicate that the primary constituents of kaolin are silicon and oxygen molecules. The presence of two distinct peaks in the spectra of …
Colloidal and Sedimentation Behavior of Kaolinite …
The analytical centrifugation analyzer LUMisizer (LUM , Germany) was used to determine the sedimentation velocities of kaolin and KLD/kaolin foci. Each measurement involved adding 1.1 mL of a clay solution (unless otherwise stated) to the instrument's cell, centrifuging it for 20 min at various speeds (200× g, 400× g, 500× g, 1000× ...
Characterization of kaolin flocs formed by polyacrylamide as
The overall objective of this work is to systematically examine the physical characteristics of kaolin flocs coagulated by aluminum sulfate in combination with PAM used as flocculants aids with different molecular weights and charge types. ... growth, breakage, re-growth and sedimentation natural were investigated by PDA2000. The results showed ...
Two-stage injection of polymer and microsand during …
Meanwhile, the turbidity and UV 254 values of settled water became lower at 30 and 180 s of sedimentation, ... FTIR and XPS analyses for surface morphological details, functional groups and chemical states of maturated flocs eventually formed in the kaolin-HA water through both two-stage injection modes. Accordingly, newly-established ...
Clay Tailings Flocculated in Seawater and Industrial Water: …
The results indicated that the maximum size of the aggregates reached between 10 and 20 s of flocculation for all evaluated physicochemical conditions. However, the presence of kaolin …
Comprehensive review of floc growth and structure using
Accurate strength values of flocs formed using CC have also been reported, including flocs that sheared at G = 50 s −1 and G = 230 s −1, with floc strengths of 0.08 and 0.42 N m −2, respectively [113]. Li et al. [56] calculated the floc strength of kaolin-alum flocs to be 0.01–0.58 N m −2, using Eq. (19). These successful cases of CC ...
(PDF) SEDIMENTATION OF KAOLIN: EFFECTS OF …
In this paper, effects of dosages and molecular weights (Mw) of branched polyethylenimine (PEI) flocculants and shear on the sedimentation of …
Evaluation of kaolin floc characteristics during coagulation …
In the water treatment industry, the formed flocs often have a large settling rate in water columns; consequently, some absorbed pollutants can be removed by sedimentation and/ or filtration ...
SEDIMENTATION OF KAOLIN: EFFECTS OF …
In this paper, effects of dosages and molecular weights (Mw) of branched polyethylenimine (PEI) flocculants and shear on the sedimentation of kaolin slurries at pH ~8 are investigated by...
Effects of humic acid on physical and hydrodynamic properties of kaolin
The physical and hydrodynamic properties of kaolin flocs including floc size, strength, regrowth, fractal structure and settling velocity were investigated by in situ particle image velocimetry technique at different humic acid concentration. Jar-test experimental results showed that the adsorbed humic acid had a significant influence on the coagulation process for alum …
Modelling and Experimental Investigation on the Settling …
In Equation (1), S i denotes the sedimentation coefficient, D i represents the diffusion coefficient, ω is the angular velocity of the rotation of the centrifugal axis, r is the radial distance from any point in the centrifugal tube to the rotation axis, and c i is the concentration of particles in the water system and is a function of time (t) and radius (r).
Compressive Yield Stress of Flocculated Kaolin Suspensions …
F-F associations form structured lamellar aggregates with a low volume and high density, known as card-pack flocs. ... Effect of flocculant dosage on the initial sedimentation rate of kaolin in SW and IW. Stirring rate 180 rpm, solids concentration 5 wt%, flocculation time 15 s, and pH 7.
A short overview of the formation of aerated flocs and their
Aerated carbon and kaolin flocs formed by the addition of a high molecular weight polymer flocculant with bubbles that are free, attached and trapped inside flocs. Sources: ... Sedimentation and flotation. R.D. Letterman (Ed.), Water Quality and Treatment: A Handbook of Community Water Supplies, McGraw-Hill (1999), p. 1248.
Clay Tailings Flocculated in Seawater and Industrial Water: …
For tailings with higher kaolin contents, the sedimentation rate tends to be constant with flocculation time. The flocculation kinetics revealed that the maximum size of the flocs was reached in the first 10–20 s. Subsequently, the destruction of the flocs was superimposed on the aggregation rate, resulting in smaller flocs as the mixing time ...
Compressive Yield Stress of Flocculated Kaolin Suspensions …
Here, the effect of two types of water, industrial water and synthetic seawater, on kaolin flocculation, sedimentation rate, yield stress, and compressive yield stress were studied. In …
Characterization of kaolin flocs formed by polyacrylamide …
EPS can form bridges between microalgal cells and small flocs which enhance the sedimentation harvesting efficiency, similar to the widely used polyacrylamide (PAM), which bridges between ...
Study on the characteristics and mechanism of the …
Kaolin particles aggregated with each other and grew to flocs under the action of small vortices created by particles filled in the flocculation section (II). Flocs further grew into large size in the expanded section (III). After flocculation, flocs were introduced into the sedimentation tank for natural settlement.
Using image texture to monitor the growth and settling of flocs
Sedimentation is a process in which the formed flocs are settled and removed by gravity. ... There are also studies evaluating the strength of Al-humus and Al-kaolin flocs according to the in situ images (Moruzzi et al. 2019), exploring a new way to monitor floc strength using computational vision. As mentioned above, computational vision is ...
Floc Kinetics in Dual-coagulation for the Treatment of High
plate and stirring paddle exist strong shear areas and produce unavoidable shear force. In general, flocs with the stronger crushing resistance and resilience are beneficial to liquid-solid separation . Flocs with the denser and tighter structure can promote the sedimentation and removal efficiencies of micro colloids and particles [18, 19 ...