Investigation of COMineralization under Dynamic Conditions in Carbonate Formations
Source: PubMed Central Open Access, NCBI / U.S. National Library of Medicine
Carbon capture and storage (CCS) via mineral trapping offers a permanent sequestration pathway; however, its slow kinetics in carbonate reservoirs remain a major challenge. This study investigates an accelerated mineralization strategy under dynamic conditions by evaluating the effectiveness of a chemical additive formulation in promoting carbonate precipitation while preserving formation integrity. Core-flooding experiments were conducted at 60 °C and 1300 psi using alternating injections of supercritical COand synthetic brine, with and without additives (0.02 M Ba(OH), 0.02 M SrCl, and 0.1 wt % GLDA glutamic acid diacetate). Rock-fluid interactions were characterized using real-time pressure monitoring, nuclear magnetic resonance (NMR) relaxometry, medical X-ray computed tomography (CT), and helium porosity measurements. The additive-free core exhibited a progressive decline in differential pressure, a net porosity increases from 16.3% to 17.25%, and a pronounced rightward shift in NMR Tdistributions, indicating extensive dissolution and wormhole formation, as confirmed by 3D CT imaging. In contrast, the additive-treated core maintained a stable pressure profile, showed negligible net porosity change (16.45% to 16.25%), and preserved its original pore-size distribution. CT imaging revealed reaction features, with substantial suppression of wormhole growth. These results demonstrate that the additive formulation effectively shifts the system from a dissolution-dominated reg
Abstract
Carbon capture and storage (CCS) via mineral trapping offers a permanent sequestration pathway; however, its slow kinetics in carbonate reservoirs remain a major challenge. This study investigates an accelerated mineralization strategy under dynamic conditions by evaluating the effectiveness of a chemical additive formulation in promoting carbonate precipitation while preserving formation integrity. Core-flooding experiments were conducted at 60 °C and 1300 psi using alternating injections of supercritical COand synthetic brine, with and without additives (0.02 M Ba(OH), 0.02 M SrCl, and 0.1 wt % GLDA glutamic acid diacetate). Rock-fluid interactions were characterized using real-time pressure monitoring, nuclear magnetic resonance (NMR) relaxometry, medical X-ray computed tomography (CT), and helium porosity measurements. The additive-free core exhibited a progressive decline in differential pressure, a net porosity increases from 16.3% to 17.25%, and a pronounced rightward shift in NMR Tdistributions, indicating extensive dissolution and wormhole formation, as confirmed by 3D CT imaging. In contrast, the additive-treated core maintained a stable pressure profile, showed negligible net porosity change (16.45% to 16.25%), and preserved its original pore-size distribution. CT imaging revealed reaction features, with substantial suppression of wormhole growth. These results demonstrate that the additive formulation effectively shifts the system from a dissolution-dominated regime to one in which acid-driven dissolution is counterbalanced by concurrent precipitation of secondary carbonate minerals. These findings strongly indicate that engineered brine chemistry can fundamentally alter CO-rock interaction pathways under dynamic flow, enabling accelerated mineral trapping while maintaining rock fabric integrity and enhancing the long-term security of geological COstorage in carbonate formations. http://www.w3.org/1999/xlink abs1 float portrait ao6c03458_0009.jpg graphical http://www.w3.org/1999/xlink tgr1 not-for-print float portrait ao6c03458_0007.jpg toc-graphic