Numerical study of proppant transport and settling processes in fractures

Conference · Sun Oct 01 00:00:00 EDT 2023

OSTI ID:2208826

Egert, Robert ^[1]; Jin, Wencheng ^[1]; Meng, Chunfang ^[2]; Fournier, Aimé ^[3]

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1. Idaho National Laboratory
2. Eden Geopower
3. Massachusetts Institute of Technology

Reservoir stimulation by creating hydraulically conductive fractures is the key step for enabling enhanced geothermal systems (EGS). The effectiveness of stimulation is significantly influenced by the deposition of proppant inside induced fractures. The transportation and settling of proppant in a propagating fracture is controlled by a multitude of operational and physical parameters, including the fracturing fluid rheology, injection rate, proppant concentration, fracture length/aperture evolution, proppant size/density/shape, etc. A numerical tool that robustly and efficiently accounts for all important attributes can facilitate the design and optimization of reservoir stimulation. This study presents the novel computational tool ELK (ELectrical fracKing) developed for the numerical simulation of proppant-fluid mixture circulation in a fractured geothermal reservoir. We enriched the MOOSE-based PorousFlow module with a suite of equations to consider the fluid-proppant mixture with particle-particle/fluid interactions, which include gravitational settling, particle convection, particle hampering, and strong density and viscosity contrasts. The computational tool is validated by comparing the predicted proppant bed evolution against two different laboratory scale experiments of proppant transport in a fixed aperture channel. Further parameter studies were performed, and the modeling results show that the proppant deposition is determined by the mixing characteristics and settling of the particles from the slurry. Concentration-dependent density and viscosity lead to an inhomogeneous distribution of the proppant, particle collision, and enhanced settling at the bottom of the fractures. Preliminary coupling with dynamic fracture propagation shows promising results and will be further developed to simulate hydraulic stimulation at high fidelity.

• Research Organization: Idaho National Laboratory (INL), Idaho Falls, ID (United States)
• Sponsoring Organization: 1
• DOE Contract Number: AC07-05ID14517
• OSTI ID: 2208826
• Report Number(s): INL/CON-23-71863-Rev001
• Conference Information: 2023 Geothermal Rising Conference, Reno, 10/01/2023 - 10/04/2023
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
EGS
Moose
Numerical modeling
Proppant transport