Dynamic Pore‐Scale Dissolution by CO 2 ‐Saturated Brine in Carbonates: Impact of Homogeneous Versus Fractured Versus Vuggy Pore Structure - Université de Montpellier Accéder directement au contenu
Article Dans Une Revue Water Resources Research Année : 2020

Dynamic Pore‐Scale Dissolution by CO 2 ‐Saturated Brine in Carbonates: Impact of Homogeneous Versus Fractured Versus Vuggy Pore Structure

Linda Luquot
Kai Zhang
  • Fonction : Auteur
  • PersonId : 1012771
Lei Zhang
  • Fonction : Auteur
  • PersonId : 1011221

Résumé

Limestone pore structure strongly influences dissolution and associated reactive transport. These effects are critical in limestone diagenesis and but also in engineering operations such as carbon capture and storage (CCS). However, detailed studies on how CO2‐enriched (acidic) brine changes this pore structure at relevant reservoir storage conditions are very limited. Thus, to provide further quantitative information and more fundamental understanding about these key processes, we studied the dissolution patterns of a homogeneous, a fractured, and a vuggy limestone when flooded with CO2‐saturated brine at representative storage conditions. The pore structured of these limestones showed drastically different responses to the acidic brine flood. As such, preferential channels surrounded by branched channels were formed in the homogeneous sample, while fractures became the main flow path in the fractured sample. In contrast, only one dominant channel formed in the vuggy sample, which resulted in a sharp permeability increase. These dissolution patterns reflect the associated Damköhler number, which significantly lower in the homogeneous, representing uniform dissolution. However, after injecting sufficient reactive fluid (1,000 PV), this uniform dissolution pattern transformed into a single preferential channel growth. Moreover, we conclude that increasing complexity of the pore geometry leads to more nonuniform dissolution. These dissolution patterns indicate the effect of initial pore structure on preferential channel growth and reaction transport. Our work provides key fundamental data for further quantifying limestone dissolution patterns in CCS, indicating that the CO2 injection may cause the reactivation of geological faults and damage around wellbore, thus aids in the implementation of industrial‐scale CCS.

Domaines

Hydrologie
Fichier principal
Vignette du fichier
2019WR026112.pdf (74.36 Mo) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte
Loading...

Dates et versions

hal-02912530 , version 1 (06-08-2020)

Identifiants

Citer

Yongfei Yang, Yingwen Li, Jun Yao, Stefan Iglauer, Linda Luquot, et al.. Dynamic Pore‐Scale Dissolution by CO 2 ‐Saturated Brine in Carbonates: Impact of Homogeneous Versus Fractured Versus Vuggy Pore Structure. Water Resources Research, 2020, 56 (4), pp.e2019WR026112. ⟨10.1029/2019WR026112⟩. ⟨hal-02912530⟩
67 Consultations
307 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More