Nathália Weber, Stephanie San Martín Cañas, Haline Rocha, Colombo Tassinari, Julio Romano Meneghini, Research Centre for Greenhouse Gas Innovation, University of São Paulo, Brazil
The Paraná Basin has a strategic location for CCUS projects in Brazil due to its proximity to regions with the highest concentration of stationary CO₂ emission sources, which could reduce risks and costs for CO₂ transportation. The evaluation of CO₂ geological storage potential of the Paraná Basin has been the focus of the CO₂ abatement program of the Research Centre for Greenhouse Gas Innovation (RCGI), at the University of São Paulo. Preliminary results identified the basin as the most prospective region, with an additional opportunity for BECCS implementation considering the high bioethanol production within the State of São Paulo. Two geological formations are targeted for reservoir characterization and injectivity assessment: the organic-rich black shales of Irati Formation, and the sandstones, coals and shales of the Rio Bonito Formation. Regarding the Irati Formation, major findings include that the source rock potential grants that the unit is suitable for the co-developing of shale gas and CO₂ geological storage in the central region of the Paraná Basin, especially in the State of São Paulo, with 11,250 km2 for an area suitable for the combined shale gas production and CO₂ geological storage perspective and another 10,500 km2 recommendable for CO₂ geological storage. Organic characterization for the Irati black shales includes type I-II kerogen, with type III also present, and early thermal maturities. In addition, it was estimated that the Irati Formation presents an injection capacity per well between 166 and 1,193 ktCO₂, with an average of around 783 ktCO₂. Further studies are being carried out to expand the analysis to estimate the total CO₂ storage capacity of the Irati Formation, identifying the best storage injection sites using predictive analyses based on machine learning algorithms. Recent efforts are concentrated on the potential for CO₂ mineralization processes in the Rio Bonito Formation, considering siliceous and carbonate cementation in its sandstones pore system. Core and pore-scale simulations and experiments from the literature indicate that although the mineralization of the injected CO₂ greatly reduces the risks of migration and leakage it may also lead to local changes in porosity and permeability, affecting the plume migration and eventually restricting CO₂ injectivity. Aiming at identifying potential mineralization pathways and impacts on CO₂ storage containment and injectivity in the Rio Bonito Formation, reservoir simulations for plume migration and injectivity assessments will be run based on inputs from geological reservoir characterization and finer scales simulations inputs, including Computational Fluid Dynamics and Molecular Dynamics, in a multiscale approach.
Acknowledgement:
We gratefully acknowledge support of the RCGI – Research Centre for Greenhouse Gas Innovation, hosted by University of São Paulo (USP) and sponsored by FAPESP – São Paulo Research Foundation (2014/50279-4 and 2020/15230-5) and Shell Brasil, and the strategic importance of the support given by ANP (Brazil’s National Oil, Natural Gas and Biofuels Agency) through the R&D levy regulation.