Influence of Ionic Strength on Clay Particle Deposition and Hydraulic Conductivity of a Sand Medium

In particle deposition problems, colloidal potentials play an important role in adsorpting the colloidal particles onto the surface of the deposit wall once the colloids arrive in the vicinity of the wall. Therefore it is important to gain understanding of these potentials, in particular, how they are influenced by the problem parameters. With such an understanding, more insights into mitigating the problem can be obtained, and consequently, more effective approaches to tackle the problem can be taken. In this work, we present the effects of particle size, flow temperature and ionic strength of the solution on the colloidal potentials based on numerical analysis. The results support the conclusion that the rate of initial deposition of particles can be reduced if the particle size is smaller, the flow temperature is increased, and the ionic strength is reduced.

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Performance of polymer-enhanced bentonite–sand mixture for covering arsenic-rich gold mine tailings for up to 4 years

Canadian Geotechnical Journal ◽

10.1139/cgj-2016-0375 ◽

2017 ◽

Vol 54 (4) ◽

pp. 588-599 ◽

Cited By ~ 7

Author(s):

M.S. Hosney ◽

R. Kerry Rowe

Keyword(s):

Ionic Strength ◽

Hydraulic Conductivity ◽

Water Content ◽

Mole Fraction ◽

Mine Tailings ◽

Direct Contact ◽

Gold Mine ◽

Confining Stress ◽

Sand Mixture ◽

Gold Mine Tailings

Experiments conducted over a 4 year period, on a polymer-enhanced bentonite–sand mixture (PEBSM) used as cover for gold mine tailings are reported. The effect on PEBSM hydraulic conductivity (k) of subgrade porewater chemistry, subgrade water content, and confining stress are investigated. Results show that the reduction in the mole fraction of bound Na+ (ESP) and corresponding increase in k of PEBSM with time was highly dependent on the ionic strength of the subgrade porewater. When the PEBSM was in direct contact with gold mine tailings with porewater having an ionic strength of 145 mmol/L, ESP decreased from 59% to 2% and k increased from 4 × 10−11 to 6.9 × 10−9 m/s. The ESP and k values of PEBSM over tailings with 11 mmol/L porewater were 21% and 6.9 × 10−11 m/s, respectively. A 0.15 m thick foundation layer between tailings and PEBSM layer significantly lowered the reduction in ESP and increase in k with time as did a reduction in the subgrade water content. There was no effect of changing confining stress from 15 to 7.5 kPa on k values of PEBSM. The PEBSM layer acted as a good barrier to the migration of arsenic from tailings upward towards cover soil above the PEBSM layer.

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Impact of hydrodynamics on clay particle deposition and biofilm development in a labyrinth-channel dripper

Irrigation Science ◽

10.1007/s00271-018-0595-7 ◽

2018 ◽

Vol 37 (1) ◽

pp. 1-10 ◽

Cited By ~ 11

Author(s):

Nassim Ait-Mouheb ◽

Juliette Schillings ◽

Jafar Al-Muhammad ◽

Ryad Bendoula ◽

Séverine Tomas ◽

...

Keyword(s):

Particle Deposition ◽

Clay Particle ◽

Labyrinth Channel ◽

Biofilm Development

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Attenuation of Cr/Pb in bauxite leachates by bentonite–polymer composite geosynthetic clay liners

RSC Advances ◽

10.1039/d0ra06921c ◽

2020 ◽

Vol 10 (73) ◽

pp. 44672-44678

Author(s):

Qin Li ◽

Daoping Peng ◽

Zheng Wu ◽

Tao Huang

Keyword(s):

Ionic Strength ◽

Hydraulic Conductivity ◽

Polymer Composite ◽

High Ionic Strength ◽

Geosynthetic Clay Liners ◽

Clay Liners ◽

High Alkalinity

Three commercially available bentonite–polymer composite geosynthetic clay liners (BPC GCLs) were selected for hydraulic conductivity testing, respectively permeated by two types of bauxite leachates with high alkalinity (pH > 12) and high ionic strength (620.3 mM).

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Interplay of stream-subsurface exchange, clay particle deposition, and streambed evolution

Water Resources Research ◽

10.1029/2002wr001432 ◽

2003 ◽

Vol 39 (4) ◽

Cited By ~ 123

Author(s):

Aaron I. Packman ◽

Jeffrey S. MacKay

Keyword(s):

Particle Deposition ◽

Clay Particle

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Influence of changes in methanol concentration on clay particle interactions

Canadian Geotechnical Journal ◽

10.1139/t89-006 ◽

1989 ◽

Vol 26 (1) ◽

pp. 57-63 ◽

Cited By ~ 5

Author(s):

John M. E. Storey ◽

J. Jeffrey Peirce

Keyword(s):

Hydraulic Conductivity ◽

Clay Particle ◽

Methanol Concentration ◽

Atterberg Limits ◽

Organic Liquids ◽

Compacted Clay ◽

Particle Settling ◽

Liner Material ◽

Clay Particles ◽

Alcohol Water

The interactions of clay particles with alcohol–water mixtures are investigated with hydraulic conductivity measurements, the electrophoretic mobilities of the suspended particles are measured, particle settling tests are carried out, and Atterberg limits are determined. Organic liquids frequently interact with clay particles in the clay liners of surface impoundments. Such fluids can cause changes in hydraulic conductivity of the liner material. This study looks at the effects of dilution of a liquid hydrocarbon with water on the properties of a clay soil. Tests with 20, 40, 60, 80, and 100% (by volume) methanol concentrations are used to investigate the changes in hydraulic conductivity of water-compacted clay samples. Particle settling tests, Atterberg limits, and electrophoretic mobility studies are used with the same concentrations to determine the effects of changing methanol concentration on clay particle behavior. The results indicate that higher concentrations of methanol cause an increase in the attraction between the clay particles, and the same concentrations also cause an increase in hydraulic conductivity. Key words: Atterberg limits, clay, electrophoresis, hydraulic conductivity, methanol, settling tests, zeta potential.

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