The Effect of Carbon Capture and Storage (CCS) on Quartz Rock and Groundwater: The case study of Thailand

Abstract

Carbon Capture and Storage (CCS) represents a critical technology for mitigating greenhouse gas emissions by capturing carbon dioxide from emission sources and its permanent sequestration in deep geological formations. This investigation examines the geochemical interactions between CO₂-saturated groundwater and quartz formations in the context of CCS implementation in Thailand's Korat basin. Quartz rock specimens were collected from the Korat basin and exposed to synthetic groundwater formulated to match the chemical composition of local groundwater samples. The synthetic solution was saturated with CO₂ to achieve acidic conditions (pH ~5), simulating the environment created during CO₂ injection. Rock-water interactions were monitored over 28 days under atmospheric conditions to assess both aqueous and solid phase transformations. Results revealed substantial geochemical evolution in both phases throughout the experimental period. Aqueous phase analysis indicated progressive increases in pH, total dissolved solids, and conductivity, consistent with dissolution and mineral trapping mechanisms. Moreover, the increasing of alkalinity, water hardness, and heavy metal concentrations (Fe, Mn, Cu, Zn, Pb, As) demonstrated active mineral dissolution and metal mobilization from the quartz matrix.  Solid phase characterization confirmed mineral precipitation processes, evidenced by a 0.18% increase in rock mass, development of calcite crystal formations, and enhanced suspended solid content. While conducted over a limited timeframe, this research underscores the complex geochemical processes associated with CCS operations and emphasizes the necessity for comprehensive impact assessment and monitoring protocols in carbon storage project development.