CO2 Capture and Storage Performance Simulation in Depleted Shale Gas Reservoirs as Sustainable Carbon Resources

Abstract

Underground carbon capture and sequestration (CCS) is a useful technique for separating this kind of greenhouse gas from atmosphere and store it under the surface of the earth. As a matter of fact, CO2 can be transferred to underground petroleum reservoirs which are initially contained oil and gas, or aquifers which are initially saturated with water. This kind of CCS takes place using an injection well which is drilled from surface to the target underground bedrocks. A shale gas reservoir (SGR) is a type of petroleum gas reservoir in which natural gas is stored in ultra-tight pores of the shale rock. In this study, a flow modeling analysis in SGR with a multi-stage fractured horizontal well (MSFHW) is conducted using numerical simulation. In this shale layer, a horizontal well is drilled and several transverse hydraulic fractures, for increasing the flow efficiency between the well and porous medium, are created. The studied SGR – a depleted reservoir acting as a macroscopic sustainable material for the CCS – is initially saturated with methane gas, and carbon dioxide is required to be injected for the storage. The most outstanding results of this study is about sensitivity analyses for SGR permeability with different conditions of gas adsorption and stress-dependent permeability which are from important features of SGRs. The results show a minor reduction in cumulative gas injection due to the effect of stress-dependent permeability in all measures for reservoir permeabilities. Furthermore, gas sorption shows a considerable positive correlation with CO2 storage response in high-permeability SGR and a minor increasing effect on SGRs with lower permeability values.

Carbon Capture and Storage in Depleted Oil and Gas Reservoirs: The Viewpoint of Wellbore Injectivity

“…Permeability is the ability of a porous medium to facilitate fluid flow and is measured in m 2 (in the metric system) or Darcy (D) or milli-Darcy (mD in the oilfield system) [68]. The permeability of a formation is closely linked to injectivity [7].…”

“…Petroleum reservoirs are porous rocks containing hydrocarbons and connate water [68]. Porosity quantifies the pore volume relative to the total volume [68].…”

“…Petroleum reservoirs are porous rocks containing hydrocarbons and connate water [68]. Porosity quantifies the pore volume relative to the total volume [68]. Naturally fractured reservoirs (NFRs) have matrices and fracture zones [68].…”

A Simulation Approach Including Underresolved Scales for Two-Component Fluid Flows in Multiscale Porous Structures

“…The numerical simulation of multicomponent fluid flows in porous regions with complex solid structures is of great importance in many industrial applications such as enhanced oil recovery including carbon dioxide injection, capture and storage [2,3], water/air flow in gas diffusion layers of fuel cells, [4][5][6], in situ copper mining by leaching [7], and sophisticated personal protective equipment [8]. To achieve high-fidelity simulation, it is crucial to fully resolve complex solid boundaries.…”

“…This approach should be applicable for various engineering cases of multiscale porous systems whose length scales typically range from micrometers to millimeters as long as the flows are well within the continuous, Stokes and capillary flow regimes. For example, hydrocarbon reservoir rocks, which are natural porous media, could contain not only intergranular pores but also microporous minerals such as clays [2,3,7]. For battery fuel cells and electrolizers in renewable energy applications, it is typical to encounter microporous electrodes separated by nanoporous membranes [4][5][6].…”