Homogenization of Dissolution and Enhanced Precipitation Induced by Bubbles in Multiphase Flow Systems. Issue 7 (6th April 2020)

• Record Type: Journal Article
• Authors: Jiménez‐Martínez, Joaquín; Hyman, Jeffrey D.; Chen, Yu; Carey, J. William; Porter, Mark L.; Kang, Qinjun; Guthrie, George; Viswanathan, Hari S.
• Is Part Of: Geophysical research letters. Volume 47:Issue 7(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-04-06
• Subjects: fluid‐solid reactions -- multiphase flow -- dissolution -- precipitation -- fractured media -- porous media; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1029/2020GL087163
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: Multiphase flow is ubiquitous in subsurface energy applications and natural processes, such as oil recovery, CO2 sequestration, and water flow in soils. Despite its importance, we still lack a thorough understanding of the coupling of multiphase flow and reaction of transported fluids with the confining media, including rock dissolution and mineral precipitation. Through the use of geomaterial microfluidic flow experiments and high‐performance computer simulations, we identify key pore‐scale mechanisms that control this coupling. We compare the reactivity of fractured limestone with CO2 ‐saturated brine (single phase) and a mixture of supercritical (sc) CO2 and CO2 ‐saturated brine (multiphase). We find that the presence of scCO2 bubbles significantly changes both the flow dynamics and the resulting reaction patterns from a single‐phase system, spatially homogenizing the rock dissolution. In addition, bubbles redirect oversaturated fluid into low‐velocity regions, thereby enhancing carbonate precipitation occurs. Plain Language Summary: The impact of pore‐scale multiphase flow on fluid‐solid reactions is poorly understood because direct observations of reactive multiphase fluids in real rock materials are not widely available and the necessary computing is intractable. Using high‐pressure/temperature geomaterial microfluidic experiments complemented by high‐performance computer direct numerical simulation of multiphase flow in those geometries, we elucidate the pore‐scale mechanisms that lead to homogenization of rock dissolution and enhancement of mineral precipitation. This study contributes to our ability to predict soil weathering and to optimize CO2 sequestration and hydrocarbon extraction. Key Points: Multiphase flow leads to homogenization of rock dissolution and enhancement of mineral precipitation The identified pore‐scale mechanisms have fundamental implications for soil weathering and subsurface applications The results provide a foundation for engineering design and predictive tools