Imperial College London
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ProfessorMartinBlunt

Faculty of Engineering, Department of Earth Science & Engineering

Chair in Flow in Porous Media
 
 
 
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Contact

 

+44 (0)20 7594 6500m.blunt Website

 
 
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Location

 

2.38ARoyal School of MinesSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Pereira:2016:10.1002/2016WR019313,
author = {Pereira, Nunes JP and Bijeljic, B and Blunt, MJ},
doi = {10.1002/2016WR019313},
journal = {Water Resources Research},
pages = {7198--7212},
title = {Pore-space structure and average dissolution rates: A simulation study},
url = {http://dx.doi.org/10.1002/2016WR019313},
volume = {52},
year = {2016}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - We study the influence of the pore-space geometry on sample-averaged dissolution rates in millimeter-scale carbonate samples undergoing reaction-controlled mineral dissolution upon the injection of a CO2 -saturated brine. The representation of the pore space is obtained directly from micro-CT images with a resolution of a few microns. Simulations are performed with a particle tracking approach on images of three porous rocks of increasing pore-space complexity: a bead pack, a Ketton oolite, and an Estaillades limestone. Reactive transport is simulated with a hybrid approach that combines a Lagrangian method for transport and reaction with the Eulerian flow field obtained by solving the incompressible Navier-Stokes equations directly on the voxels of three-dimensional images. Particle advection is performed with a semianalytical streamline method and diffusion is simulated via a random walk. Mineral dissolution is defined in terms of the particle flux through the pore-solid interface, which can be related analytically to the batch (intrinsic) reaction rate. The impact of the flow heterogeneity on reactive transport is illustrated in a series of simulations performed at different flow rates. The average dissolution rates depend on both the heterogeneity of the sample and on the flow rate. The most heterogeneous rock may exhibit a decrease of up to two orders of magnitude in the sample-averaged reaction rates in comparison with the batch rate. Furthermore, we provide new insights for the dissolution regime that would be traditionally characterized as uniform. In most cases, at the pore-scale, dissolution preferentially enlarges fast-flow channels which greatly restricts the effective surface available for reaction.
AU  - Pereira,Nunes JP
AU  - Bijeljic,B
AU  - Blunt,MJ
DO  - 10.1002/2016WR019313
EP  - 7212
PY  - 2016///
SN  - 0043-1397
SP  - 7198
TI  - Pore-space structure and average dissolution rates: A simulation study
T2  - Water Resources Research
UR  - http://dx.doi.org/10.1002/2016WR019313
UR  - http://hdl.handle.net/10044/1/42637
VL  - 52
ER  -
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