(554c) Lattice Boltzmann Modeling of Transport and Deposition of Nanoparticles in the Pore Network of Berea Sandstone

The fate and transport of nanoparticles in the porous space of an aquifer or a hydrocarbon reservoir rock has attracted considerable consideration for environmental, as well as enhanced oil recovery applications. In this study, the propagation and kinetics of nanoparticles inside the pore space of consolidated Berea sandstone are numerically investigated. The 3D geometry of the rock is reconstructed from 2D grayscale images, yielded after scanning the rock sample by a micro-CT machine. Later on, 2D image analysis is employed to quantitatively characterize the pore network, in which the pore size distribution and the contribution of each pore type (dead-end, isolated, and fully-connected pores) to the total pore space are determined. A lattice Boltzmann method (LBM) is used to simulate the velocity field of water flowing in the pore space of the actual sandstone. This simulation is equivalent to core flooding experiments, as they are known in the petroleum engineering literature. In association with that, a Lagrangian particle tracking (LPT) algorithm is utilized to track the trajectories of nanopaticles moving under the convective effect of the flow and a diffusive effect because of molecular diffusion [1]. It is assumed in the model that the size exclusion effect is not involved in particle retention. The particle adsorption on the pore surfaces is modeled as a pseudo-first order adsorption. Effects of different factors to the particle breakthrough are considered such as particle size, pore velocity, and excluded area. The role of pore surface heterogeneity is also addressed. The presentation will discuss both the numerical model for simulating the particle propagation, adsorption, and desorption, but also the validation of the technique with experiments leading to the determination of exactly what interactions are important when carbon nanotubes move through aquifers and reservoirs. 

ACKNOWLEDGEMENTS

The financial support of the Advanced Energy Consortium (AEC BEG08-022) and the computational support of XSEDE (CTS090017) are acknowledged.

REFERENCES

1. Voronov, R.S., VanGordon, S., Sikavitsas, V.I., and D.V. Papavassiliou, “Efficient Lagrangian scalar tracking method for reactive local mass transport simulation through porous media,” Int. J. for Numerical Methods in Fluids, 67, 501-517, 2011