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Remediation of colloid-facilitated contaminant transport in saturated porous media treated by nanoparticles
Arab, D.; Pourafshary, P.; Ayatollahi, Sh. & Habibi, A.
Abstract
Facilitation of contaminant transport in porous
media due to the effect of indigenous colloidal fine materials
has been widely observed in laboratory and field
studies. It has been explained by the increase in the
apparent solubility of low soluble contaminants as a result
of their adsorption on the surface of fine particles.
Attachment of colloidal fine particles onto the rock surface
could be a promising remedy for this challenge. In this
experimental study, the effect of five types of metal oxide
nanoparticles, γ-Al2O3, ZnO, CuO, MgO, and SiO2, on
suspension transport was investigated. In several core
flooding tests, different nanofluids were used to saturate the
synthetic porous media. Subsequently, after sufficient
soaking time, the suspension was injected into the treated
porous media. Analysis of the effluent samples’ concentration
by Turbidimeter apparatus demonstrated that the
presence of nanoparticles on the rock surface resulted in a
significant reduction in fine concentrations in the effluent
samples compared with non-treated media; ZnO and γ-
Al2O3 demonstrated the best scenarios among the tests
performed in this study. In order to characterize the surface
properties of the treated porous media, the zeta potential of
the surface was measured. Results showed that the treated
porous media acts as a strong adsorbent of fine particles,
which are the main carrier of contaminants in porous
media. These findings were quantitatively confirmed by
calculation of the total energy of interaction between the
fine particles and rock surface
Keywords
Fine particles migration; Groundwater; Nanotechnology; Porous media; Subsurface colloids; Zeta potential alteration
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