TY  - JOUR
AU  - Ahmed, Mohammed Mahtab
AU  - Hassan, Amjed
AU  - Khan, Fahad
AU  - Raza, Arshad
AU  - Gajbhiye, Rahul
AU  - Mahmoud, Mohamed
PY  - 2026
DA  - 2026/10/01
TI  - Chemical Pre-Flush and Additive Strategies to Enhance CO$_2$ Solubility and Injectivity in Deep Saline Aquifers: Mechanisms, Evidence, and Field Readiness
JO  - Reservoir Science
T2  - Reservoir Science
JF  - Reservoir Science
VL  - 3
IS  - 1
SP  - 1
EP  - 25
DO  - 10.62762/RS.2026.344933
UR  - https://www.icck.org/article/abs/RS.2026.344933
KW  - deep saline aquifers
KW  - solubility trapping
KW  - salt precipitation
KW  - low-salinity pre-flush
KW  - chelating agents
KW  - CO2 foam
KW  - CO2-soluble surfactants
KW  - nanoparticles
AB  - Deep saline aquifers offer the largest global capacity potential for geologic carbon storage, yet storage performance is frequently constrained by coupled limitations on \COtwo{} dissolution (solubility trapping) and injectivity under high-salinity conditions. Elevated ionic strength suppresses \COtwo{} solubility via ``salting-out'' effects. Meanwhile, near-wellbore dry-out during injection of dry or undersaturated \COtwo{} can concentrate brine and precipitate salts, reducing permeability and injectivity. Mineralogy and \COtwo{}-brine-rock wettability further control multiphase flow topology, interfacial area for dissolution, capillary trapping, and compatibility of additives with reservoir surfaces. This review critically evaluates chemical pre-flush and additive-enabled conditioning strategies intended to (i) increase local aqueous \COtwo{} dissolution capacity, (ii) mitigate or prevent dry-out-driven salt precipitation and near-wellbore formation damage, and (iii) enhance \COtwo{}-brine contact through mobility control. We synthesize and compare evidence for four strategy families: (1) freshwater and engineered low-salinity (LoSal) pre-flush slugs and intermittent re-wetting; (2) chelating agents (e.g., EDTA/GLDA/DTPA) that complex multivalent cations and alter dissolution/precipitation pathways; (3) surfactant-derived \COtwo{} foams, including \COtwo{}-soluble surfactants designed for foam generation at the displacement front with achievable injectivity; and (4) nanoparticle-assisted and hybrid foam systems that extend foam stability under harsh salinity and temperature.
SN  - 3070-2356
PB  - Institute of Central Computation and Knowledge
LA  - English
ER  - 

@article{Ahmed2026Chemical,
  author = {Mohammed Mahtab Ahmed and Amjed Hassan and Fahad Khan and Arshad Raza and Rahul Gajbhiye and Mohamed Mahmoud},
  title = {Chemical Pre-Flush and Additive Strategies to Enhance CO\$\_2\$ Solubility and Injectivity in Deep Saline Aquifers: Mechanisms, Evidence, and Field Readiness},
  journal = {Reservoir Science},
  year = {2026},
  volume = {3},
  number = {1},
  pages = {1-25},
  doi = {10.62762/RS.2026.344933},
  url = {https://www.icck.org/article/abs/RS.2026.344933},
  abstract = {Deep saline aquifers offer the largest global capacity potential for geologic carbon storage, yet storage performance is frequently constrained by coupled limitations on \COtwo{} dissolution (solubility trapping) and injectivity under high-salinity conditions. Elevated ionic strength suppresses \COtwo{} solubility via ``salting-out'' effects. Meanwhile, near-wellbore dry-out during injection of dry or undersaturated \COtwo{} can concentrate brine and precipitate salts, reducing permeability and injectivity. Mineralogy and \COtwo{}-brine-rock wettability further control multiphase flow topology, interfacial area for dissolution, capillary trapping, and compatibility of additives with reservoir surfaces. This review critically evaluates chemical pre-flush and additive-enabled conditioning strategies intended to (i) increase local aqueous \COtwo{} dissolution capacity, (ii) mitigate or prevent dry-out-driven salt precipitation and near-wellbore formation damage, and (iii) enhance \COtwo{}-brine contact through mobility control. We synthesize and compare evidence for four strategy families: (1) freshwater and engineered low-salinity (LoSal) pre-flush slugs and intermittent re-wetting; (2) chelating agents (e.g., EDTA/GLDA/DTPA) that complex multivalent cations and alter dissolution/precipitation pathways; (3) surfactant-derived \COtwo{} foams, including \COtwo{}-soluble surfactants designed for foam generation at the displacement front with achievable injectivity; and (4) nanoparticle-assisted and hybrid foam systems that extend foam stability under harsh salinity and temperature.},
  keywords = {deep saline aquifers, solubility trapping, salt precipitation, low-salinity pre-flush, chelating agents, CO2 foam, CO2-soluble surfactants, nanoparticles},
  issn = {3070-2356},
  publisher = {Institute of Central Computation and Knowledge}
}