Simulation of experimental breakthrough curves using multiprocess non-equilibrium model for reactive solute transport in stratified porous media

Abstract

In this paper, we have studied the behaviour of reactive solute transport through stratified porous medium under the influence of multi-process nonequilibrium transport model. Various experiments were carried out in the laboratory and the experimental breakthrough curves were observed at spatially placed sampling points for stratified porous medium. Batch sorption studies were also performed to estimate the sorption parameters of the material used in stratified aquifer system. The effects of distance dependent dispersion and tailing are visible in the experimental breakthrough curves. The presence of physical and chemical non-equilibrium are observed from the pattern of breakthrough curves. Multi-process non-equilibrium model represents the combined effect of physical and chemical non-ideality in the stratified aquifer system. The results show that the incorporation of distance dependent dispersivity in multi-process non-equilibrium model provides best fit of observed data through stratified porous media. Also, the exponential distance dependent dispersivity is more suitable for large distances and at small distances, linear or constant dispersivity function can be considered for simulating reactive solute in stratified porous medium.

Non-reactive solute transport modelling with time-dependent dispersion through stratified porous media

“…A skewed shape of experimental and simulated results has been obtained as shown in figures 3, 4, 5, 6, 7 and 8, which is a clear demonstration that the system is under the strong influence of physical nonequilibrium. In the experimental set-up of Swami et al [24], the width of the immobile region is large and that is the reason behind the long tails with a high concentration at the concluding part of the experiments. MIM with time-dependent dispersion has demonstrated capabilities to simulate such complex scenario in pre-asymptotic regime.…”

“…It has been observed that the mass transfer coefficient contributes in early arrival and long tailing of BTC apart from retardation factor and dispersion coefficient [16]. In addition to this, the most challenging aspect of studying solute transport through heterogeneous porous media is ever-growing scale effect with space or time on the estimation of dispersion coefficient [17][18][19] since constant dispersion coefficient is a lumped parameter and unable to capture the broad spectrum of time scale BTCs through a heterogeneous porous medium [20][21][22][23][24]. To incorporate the scale effects, time-dependent and scale (distance)-dependent dispersion models in pre-asymptotic regime have been developed over the past decade [8,[25][26][27][28].…”

Analysis of two-dimensional solute transport through heterogeneous porous medium

“…Ku mar, et al and the respective initial and boundary conditions Eqs. (18)(19)(20) may be written in terms of ( , ) K Z t , as follows 00 00 ( , ) exp 2 22), i.e., to reduce it into an ordinary differential equation of second order, let us multiply its both sides by exp( ) pt  and integrate it between the limit 0 t  and t , i.e., applying Laplace transformation of parameter p on equation (22), we get 2 0 2 00…”

Experimental Design of Physical Unconfined Aquifer for Evaluation of Well Abstraction Effects: Laboratory Approach

“…The recharge conditions are decreasing due to deforestation and concrete structure build up in large area of urbanization [4] .Climate change also has significant impacts on ground water [5]. Contamination due to land fill and chemical waste from industry are equally responsible for degradation of quality ground water [6][7][8]. Unplanned settlement, bored well and deep well constructions are causing to disturbing the water balance condition.…”