ZHANG Peng-yuan, BAI Bing, JIANG Si-chen. Coupled effects of hydrodynamic forces and pore structure on suspended particle transport and deposition in a saturated porous medium[J]. 2016, 37(5): 1307-1316.
DOI:
ZHANG Peng-yuan, BAI Bing, JIANG Si-chen. Coupled effects of hydrodynamic forces and pore structure on suspended particle transport and deposition in a saturated porous medium[J]. 2016, 37(5): 1307-1316.DOI: 10.16285/j.rsm.2016.05.012.
Coupled effects of hydrodynamic forces and pore structure on suspended particle transport and deposition in a saturated porous medium
To investigate the effects of pore structure and hydrodynamic forces on the particle transport and deposition
the penetration processes of a typical silica powder (suspended particles) and fluorescein (as the dissolved tracer) in saturated porous media is studied through a series of column tests. Two kinds of porous media (i.e.
quartz sand and glass beads) and 5 seepage velocities (i.e.
0.033
0.066
0.132
0.199
0.265 cm/s) are considered
and twenty breakthrough curves are obtained. Based on the experimental results
the influence of pore structure and seepage velocity on the hydrodynamic mechanism
dispersion effects and accelerated effects are analyzed during deposition and migration processes of suspended particles in saturated porous media. It is shown that
the breakthrough curves (BTCs) are well described by an analytical solution of the advective-dispersive equation with a first-order deposition kinetics. In contrast with the effect of pore structure
the effect of hydrodynamics processes on particle transport increases significantly with the increase of seepage velocity. There exists a critical seepage velocity
beyond which suspended particles travel faster than the dissolved tracer
and the critical velocity is different for glass beads and quartz. In addition
the mean diameter of the recovered particles
the longitudinal dispersivity and recovery rate increase with the seepage velocity
and a decrease of the deposition rate of particles beyond the critical seepage velocity is also observed in two porous media. Furthermore
the recovery rate of suspended particles is higher in the glass beads even if the porosities are similar. Overall
the study highlights the effect of pore structure and seepage velocity on the transport of particles in saturated porous media
and the pore structure even plays a greater role in high seepage velocity conditions.