scholarly journals Laboratory column experiments for radionuclide adsorption studies of the Culebra dolomite member of the Rustler Formation

1998 ◽  
Author(s):  
D.A. Lucero ◽  
C.E. Heath ◽  
G.O. Brown
Keyword(s):  
Column Experiments ◽  
Adsorption Studies ◽  
Laboratory Column

Experimental and numerical investigation of microparticle transport and deposition in the context of permafrost thaw

2021 ◽  
Author(s):  
Madiha Khadhraoui ◽  
John Molson ◽  
Najat Bhiry
Keyword(s):  
Porous Media ◽  
Pore Water ◽  
Water Velocity ◽  
Kinetic Term ◽  
Column Experiments ◽  
Order Kinetic ◽  
Permafrost Degradation ◽  
Pore Water Velocity ◽  
Laboratory Column ◽  
Study Laboratory

<p>In natural porous environments, soil particle migration during flow plays an important role in soil stability and pollutant transport by affecting soil mechanical properties and water quality. In northern areas, permafrost degradation alters the subsurface connection pathways leading to mass movements and rearrangement of the soil. To date, few models have included the influence of temporal and spatial variations of flow velocity and porous media heterogeneity on the transport and deposition of suspended particles.</p><p>In this study, laboratory column experiments and a numerical model were used to investigate these issues. The laboratory column experiments were carried out under different flow rates and the effect of porous media heterogeneity was investigated using different grain size distributions. The soil columns were reconstituted from several samples taken in the studied site, the Tasiapik Valley, located in the discontinuous permafrost zone near Umiujaq, Nunavik, Québec. During the experiments, the spatio-temporal distribution of the porosity and the hydraulic conductivity was monitored using X-ray computed tomography imaging (CT-SCAN). Using the pore water velocity computed from the groundwater flow solution, the advection–dispersion transport equation with a first-order kinetic term for particle deposition was solved using the finite element model Heatflow/Smoker. The dependency of the attachment kinetics on the pore water velocity and on the porous media heterogeneity was included. The model was tested and validated with an analytical solution and calibrated with the experimental data. Our simulations highlight the roles of hydrodynamic conditions and soil characteristics on particle transport and deposition mechanisms and the susceptibility of the porous medium to thermo-suffosion in permafrost environments.</p>

Lead migration in smelter-impacted deciduous and coniferous organic soil horizons based on a long-term in-situ implantation and laboratory column experiments

2014 ◽  
Vol 48 ◽  
pp. 168-175 ◽  
Author(s):  
Vladislav Chrastný ◽  
Aleš Vaněk ◽  
Eva Čadková ◽  
Alice Růžičková ◽  
Ivana Galušková ◽  
...  
Keyword(s):  
Organic Soil ◽  
Column Experiments ◽  
Soil Horizons ◽  
Laboratory Column

scholarly journals Transient groundwater chemistry near a river: Effects on U(VI) transport in laboratory column experiments

2011 ◽  
Vol 47 (4) ◽  
Author(s):  
Jun Yin ◽  
Roy Haggerty ◽  
Deborah L. Stoliker ◽  
Douglas B. Kent ◽  
Jonathan D. Istok ◽  
...  
Keyword(s):  
Groundwater Chemistry ◽  
Column Experiments ◽  
Laboratory Column

Long term laboratory column experiments to simulate bank filtration: Factors controlling removal of sulfamethoxazole

2011 ◽  
Vol 45 (1) ◽  
pp. 211-220 ◽  
Author(s):  
Benno Baumgarten ◽  
Jeannette Jährig ◽  
Thorsten Reemtsma ◽  
Martin Jekel
Keyword(s):  
Column Experiments ◽  
Bank Filtration ◽  
Laboratory Column

scholarly journals Effects of Environmental Factors on the Leaching and Immobilization Behavior of Arsenic from Mudstone by Laboratory and In Situ Column Experiments

Minerals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1220
Author(s):  
Takahiko Arima ◽  
Ryosuke Sasaki ◽  
Takahiro Yamamoto ◽  
Carlito Baltazar Tabelin ◽  
Shuichi Tamoto ◽  
...  
Keyword(s):  
Water Content ◽  
Adsorption Layer ◽  
River Sediment ◽  
Column Experiments ◽  
Experimental Conditions ◽  
Natural Adsorbents ◽  
In Situ Experiments ◽  
As Adsorption ◽  
Laboratory Column

Hydrothermally altered rocks generated from underground/tunnel projects often produce acidic leachate and release heavy metals and toxic metalloids, such as arsenic (As). The adsorption layer and immobilization methods using natural adsorbents or immobilizer as reasonable countermeasures have been proposed. In this study, two sets of column experiments were conducted, of which one was focused on the laboratory columns and other on the in situ columns, to evaluate the effects of column conditions on leaching of As from excavated rocks and on adsorption or immobilization behavior of As by a river sediment (RS) as a natural adsorbent or immobilizer. A bottom adsorption layer consisting of the RS was constructed under the excavated rock layer or a mixing layer of the excavated rock and river sediment was packed in the column. The results showed that no significant trends in the adsorption and immobilization of As by the RS were observed by comparing laboratory and in situ column experiments because the experimental conditions did not influence significant change in the leachate pH which affects As adsorption or immobilization. However, As leaching concentrations of the in situ experiments were higher than those of the laboratory column experiments. In addition, the lower pH, higher Eh and higher coexisting sulfate ions of the leachate were observed for the in situ columns, compared to the results of the laboratory columns. These results indicate that the leaching concentration of As became higher in the in situ columns, resulting in higher oxidation of sulfide minerals in the rock. This may be due to the differences in conditions, such as temperature and water content, which induce the differences in the rate of oxidation of minerals contained in the rock. On the other hand, since the leachate pH affecting As adsorption or immobilization was not influenced significantly, As adsorption or immobilization effect by the RS were effective for both laboratory and in situ column experiments. These results indicate that both in situ and laboratory column experiments are useful in evaluating leaching and adsorption of As by natural adsorbents, despite the fact that the water content which directly affects the rate of oxidation is sensitive to weathering conditions.

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