CCUS Operational Challenges: Lessons Learned from the World's Largest Offshore Carbon-Capture, Utilization and Storage Initiative in the Oil and Gas Industry

Abstract To incorporate an effective CCUS strategy in the already challenging reality of offshore oil and gas production, a broad range of multidisciplinary technologies with seamless interconnections have been required to successfully ensure highly efficient and safe operations in the Brazilian pre-salt reserves. Taking advantage of the flexible conception of topside facilities, tailormade EOR strategies could be established. Water-alternating-gas and design of gas composition and volume injected are typically employed to maximize oil and gas production throughout the exploration period. Carbon capture through CCUS-anchored solutions have been playing a key role since the beginning of the exploratory efforts in the pre-salt layer of the Brazilian coast. Since the conceptual phase of the first projects in the area, the cutting-edge production strategy in pre-salt fields with CO2 content anticipated a much-needed boost in the CCUS technologies developments. Several CCUS initiatives made possible to achieve the milestone of 40.8 million tons of CO2 reinjected, cumulatively (2008 – 2022), into the pre-salt reservoirs associated with EOR and contributed to place the greenhouse gases (GHG) production intensity in the pre-salt fields in the first quartile of the industry. Solely, in 2022 Petrobras reinjected 10.6 MtCO2 back into reservoirs. Therefore, the CCUS project developed by Petrobras is one of the main enablers of the development of the gigantic deepwater oil fields in the pre-salt Santos Basin - the first of its kind.