Institute for Modelling Hydraulic and Environmental Systems Department of Hydromechanics and Modelling of Hydrosystems
Development and Implementation of a Gold Mobility Model
Goldschmidt 2017, Paris
M. Mohajer, J. Hommel, J. Shuster,
F. Reith
Geomartin own work, CC-BY-SA 4.0,
https://commons.wikimedia.org/w/index.php?curid=53553700
What is the Scope of the Model?
https://goldsamples.wordpress.com/
Subsurface biogeochemical gold (Au) mobilization, transport, and precipitation
Reactions and Processes in the Simplified Model
Model Scale and Primary Variables
• Large spatial scales of interest in applications modelling on REV scale using volume averaged quantities:
• Mole fractions (mobile components)
• Volume fractions (solids)
Mass Balance Equations
Mass Balance Equations
• Mass balance equation of components exclusively in the water phase:
Mass Balance Equations
• Mass balance equation of components exclusively in the water phase:
• Mass balance for the immobile components / solid phases:
Sources and Sinks: Reactions
Biomass, Substrate and Ligands
Biomass, Substrate and Ligands
Gold Dissolution and Precipitation
Gold Dissolution and Precipitation
Gold NP Mobility and Aggregation
Gold NP Mobility and Aggregation
Test Setup
• Bronze Age settlement in Bavaria: Gold artifacts real or fake?
• Boundary and initial conditions relatively well known
rain, substrate
no flow
sides: Dirichlet BC = initial conditions, no gold species or substrate
Preliminary Results
t = 1 year
dissolving biomass [kg/m³]
0 0.06 0 5.0 cyanide [mol/m³]
Preliminary Results
Au complexes [mol/m³]
0 0.021 0 5.0 cyanide [mol/m³]
t = 1 year
Preliminary Results
initial „large“ Au Au species distribution at t = 1 year
Conclusions and Outlook
• The developed model qualitatively reproduces expected behaviour.
• Future work: Calibrate and validate the model using a variety of experiments at different scales
Combined modeling and experimental investigations will improve the model, the experiments and the understanding of gold cycling
Thank you!
phone +49 (0) 711 685- fax +49 (0) 711 685- University of Stuttgart
Institute for Modelling Hydraulic and Environmental Systems Department of Hydromechanics and Modelling of Hydrosystems Pfaffenwaldring 61, D-70569 Stuttgart, Germany
Johannes Hommel
64600
Johannes.hommel@iws.uni-stuttgart.de
M. Mohajer, J. Hommel, J. Shuster,
F. Reith
Preliminary Results
initial „large“ Au Au species distribution at t = 1 year initial „large“ Au no Au complex precipitation by clay/OM with
