Development of a trajectory model for predicting attachment of submicrometer particles in porous media: Stabilized NZVI as a case study
Journal
Environmental Science and Technology
Journal Volume
44
Journal Issue
23
Pages
8996-9002
Date Issued
2010
Abstract
A new trajectory simulation algorithm was developed to describe the efficiency of a single collector (pore) to catch submicrometer particles moving through saturated porous media. A constricted-tube model incorporating the deterministic (interception, hydrodynamic retardation, van der Waals force and gravitational sedimentation), stochastic (Brownian diffusion), and thermodynamic (electrostatic and steric repulsion force) mechanisms was established to predict the transport and deposition of surface modified nanoscale zerovalent iron (NZVI) particles by applying Lagrangian trajectory analytical approach. The simulation results show good agreement with the results predicted by existing energy-barrier-free models except for the particle size less than 100 nm at low approach velocity. The number of realizations per start location could be decreased down to 100 with the simulations still exhibiting acceptable relative standard deviation for engineering purposes. With the consideration of energy barriers, the model successfully describes the breakthrough curve of polymer-modified NZVI in a benchtop soil column as well. The novel simulation scheme can be a useful tool for predicting the behavior of the nanoscale colloidal particles moving through filter beds or saturated soil columns under conditions with repulsion and attraction forces among surfaces. © 2010 American Chemical Society.
SDGs
Other Subjects
Collector efficiency; Energy barriers; Forecasting; Nanotechnology; Particle separators; Particle size; Porous materials; Sedimentation; Stochastic systems; Trajectories; Van der Waals forces; Gravitational sedimentation; Hydrodynamic retardation; Lagrangian trajectories; Nanoscale zero-valent iron; Relative standard deviations; Saturated porous media; Submicrometer particle; Trajectory simulation; Stochastic models; iron derivative; nanoscale zerovalent iron; unclassified drug; algorithm; colloid; diffusion; energy efficiency; hydrodynamics; interception; iron; Lagrangian analysis; numerical model; particle size; polymer; porous medium; sedimentation; soil column; stabilization; stochasticity; thermodynamics; velocity; algorithm; analytic method; article; Brownian diffusion; colloid; diffusion; energy transfer; entropy; filter; gravitational sedimentation; hydrodynamics; Lagrangian trajectory; nanoanalysis; particle size; polymerization; porosity; sedimentation; simulation; static electricity; steric repulsion force; stochastic model; submicrometer particle; thermodynamics
Type
journal article