91Ö±²¥

Jointly sponsored by EPSRC (EP/I010971/1) and NSFC China

Carbon capture and storage (CCS) has been recognised as one of the measures needed to mitigate climate change. Emitting is avoided by capturing CO2 from stationary sources and transporting it into a suitable storage location. Geological storage in deep saline aquifers is one of the most favourable storage options due to its wide availability and large storage space.

Our research aims at developing fundamental understanding and quantitative description of CO2 migration in porous media at conditions relevant to saline aquifers encountered in carbon sequestration, and hence contributing to mitigating climate change.

The project brings together engineers and geologists from the UK and China to undertake a comprehensive research programme comprising combined experimental (flow and mineral-fluid interactions), computational and theoretical investigations. The complex two-phase flow phenomena in porous rocks are experimentally investigated using a purposely-built supercritical CO2 test facility equipped with a Custom-built MRI at Tsinghua operating at conditions typical of deep saline aquifers.

Complementary experiments on mineral-fluid interactions are conducted at Leeds studying the interactions between the fluids and rocks reactions of the rocks. The computational studies led by 91Ö±²¥ employ various numerical techniques, combining mesoscale modelling using Lattice Boltzmann Method (LBM), multi-physics modelling and conventional CFD to investigate the two-phase flow physics, and fluid-fluid and fluid-rock interactions at sub-pore levels.

The ultimate aim of the investigations is to use the new experimental and computational data to produce correlations/relationships for use with large scale simulations as well as developing further fundamental understanding of phenomena of CO2/brine two-phase flow in porous media.

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Simulations

The computational studies employ various numerical techniques, combining mesoscopic modelling using Lattice Boltzmann Method (LBM), multi-physics modelling and conventional CFD to investigate the two-phase flow physics, and fluid-fluid and fluid-rock interactions at sub-pore levels:

i) An efficient two-phase flow LBM model for application of modelling CO2 migration in brine has been developed based on evaluating, comparing and improving the various existing models, which will be optimised for the particular fluid properties and thermodynamic conditions.

ii) a finite-volume solver for the fundamental equations governing the basic flow phenomena is being developed based on first principles to describe flows at sub-pore levels, but with simplifications taking advantage of the low flow rate conditions to reduce computing resources. Both of the above solvers will then be used to study the physical problems and generate further detailed information which is not available from experiments.

iii) Exercises using CFD simulations with commercial software are also being undertaken which will produce complementary data to compare with our new methods.

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LBM for Brine/CO2 Flow in Rocks (91Ö±²¥ & Leeds)

CFD of CO2 Migration and Fluid-rock Reaction (Tsinghua, Leeds, Aberdeen & 91Ö±²¥)

CFD Based on Stoke Flow (Aberdeen & 91Ö±²¥)

Publications

• Zu, Y and He, S (2012) Lattice Boltzmann modelling of migration for CO2 in porous media under conditions of saline aquifers, Int. Sym. Heat Transfer, ISHT-8, Oct 21-24, Beijing, China.
• Zu, Y and He, S (2013) Phase-field-based lattice Boltzmann model for incompressible binary fluid systems with density and viscosity contrasts, Phys. Rev. E 87, 043301.
• Lamy-Chappuis, B., Angus, D., Fisher, Q., Granttoni, C., and Yardley, B.W.D (2014) Rapid porosity and permeability changes of calcareous sandstone duo to CO2-enriched brine injection, Geophy. Res. Lett., 41, doi: 10.1002/2013GL058534.
• Jiang, P., Li, X., Xu, R., Wang, Y., Chen, M., Wang, H., and Ruan, B (2014) Thermal modelling of CO2 in the injection well and reservoir at the Ordos CCS demonstration project, China, Int. J. Greenhouse Gas Control 23, 135-146.
• Xie, JF, He, S., Zu, Y., Lamy-Chappuis, B., and Yardley, B.W.D (2014) Numerical investigations of relative permeabilities of CO2 and brine in carbon sequestration using the lattice Boltzmann method (preprinted to be submitted).