CO2-Brine flow in Nubian Sandstone (Egypt): Pore Network Modeling using Computerized Tomography Imaging
Abstract
The injection of CO2 into the highly permeable Nubian Sandstone of a depleted oil field in the central Gulf of Suez Basin (Egypt) is an effective way to extract enthalpy from deep sedimentary basins while sequestering CO2, forming a so-called CO2-Plume Geothermal (CPG) system. Subsurface flow models require constitutive relationships, including relative permeability and capillary pressure curves, to determine the CO2-plume migration at a representative geological scale.
Based on the fluid-displacement mechanisms, quasi-static pore-network modeling has been used to simulate the equilibrium positions of fluid-fluid interfaces, and thus determine the capillary pressure and relative permeability curves. 3D images with a voxel size of 650 nm3 of a Nubian Sandstone rock sample have been obtained using Synchrotron Radiation X-ray Tomographic Microscopy. From the images, topological properties of pores/throats were constructed.
Using a pore-network model, we performed a cycle of primary drainage of quasi-static invasion to quantify the saturation of scCO2 at the point of a breakthrough with emphasis on the relative permeability–saturation relationship. We compare the quasi-static flow simulation results from the pore-network model with experimental observations. It shows that the Pc-Sw curve is very similar to those observed experimentally. Show more
Permanent link
https://doi.org/10.3929/ethz-b-000445810Publication status
publishedBook title
Proceedings of the European Geothermal Congress 2019Pages / Article No.
Publisher
EGECEvent
Subject
Pore-Network Modeling; CO2-plume geothermal; Nubia sandstone; Residual trappingOrganisational unit
09494 - Saar, Martin O. / Saar, Martin O.
Related publications and datasets
Is part of: https://doi.org/10.3929/ethz-b-000445518
More
Show all metadata
ETH Bibliography
yes
Altmetrics