nZVI Mobility and Transport: Laboratory Test and Numerical Model

Zerovalent iron nanoparticles (nZVI) are becoming one of the most widely recommended nanomaterials for soil and groundwater remediation. However, when nZVI injected in flow, behavior (mobility, dispersion, distribution) is practically unknown. This fact generally results use enormous quantities them at field scale. The uncertainties on effective volumes reached from plume because their tendency to aggregate weight can cause settling deposition. So, mobility a real issue, which often lead inefficient or expensive Furthermore, there another aspect that must be considered: fate these possible impact subsoil environment. All considerations have led us propose an application simulating permeation technique through laboratory experience, finalized better, even simpler description flow subsoil. A two-dimensional laboratory-scale tank was used study dispersion transport nZVI. solution, with concentration equal 4.54 g/L, into glass beads, utilized as porous medium. experiment included digital camera acquire images. images were then calibrating numerical model. mass balance confirm validity proposed model, obtaining values velocity (5.41 × 10?3 m/s) (1.9 g) same order those experimental tests. Several information inferred both Both demonstrate does not behave solute dissolved water, but showing its own ruled mainly buoyancy force. simple simulation tracer input compared evidence large differences between evolution time space. means commercial models, if corrected, cannot furnish forecast volume influence Further deductions found confirmed by model where detachment effect much smaller than attachment (ratio kd/ka = 0.001). From what reported, it worthwhile pay attention localization contaminants source/plume reach treatment important go further improvement solution limiting aggregation phenomenon.