Time Lapse Measurement of Reservoir’s Parameters Change due to CO₂ Injection in Parigi Carbonate West Java

Abstract

CO2 injection is a process that involves injecting carbon dioxide gas into various substances or environments for different purposes. This technique, also called Carbon Capture and Storage (CCS) or Carbon Capture, Utilization, and Storage (CCUS), aims to prevent or reduce carbon dioxide emissions from reaching the atmosphere as they would affect climate change and also global warming. CCUS can also use the captured carbon dioxide for various purposes, such as enhancing oil recovery, producing fuels, chemicals, or building materials, or storing it underground or underwater. In this study, we investigated the phenomena of CO2 injection in Parigi carbonate rock from West Java. Our study involved various laboratory measurements of Parigi carbonate rock, focusing on changes in porosity due to CO2 injection. The porosity changes were observed using micro images analysis from microscope time-lapse analysis, CT-Scan, and laboratory helium porosity meter. The laboratory measurements of CO2 injection in brine water showed that the pH of the water can decrease to below 5, creating an acidic environment that induces dissolution of the pore structure. We measure the effect of CO2 injection to the Parigi carbonate samples by time lapse measurement strategy. Results of the laboratory measurements showed that the porosity increased during CO2 injection and the mass of the samples decreased during the CO2 injection process. These phenomena suggest that CO2 may induce dissolution of carbonate rock. Furthermore, the changes in porosity confirm that there is a chemical reaction during CO2 injection processes in Parigi carbonate.