Post Combustion CO₂ Capture Plant for Offshore Gas Turbine Generators (GTGs) – Qualification Process Available to Purchase

The purpose of this paper is to present the results of the Petrobras' endeavors in assessing the technical feasibility for the installation of a CO₂ capture plant from exhaust gas generated at the GTGs on a forthcoming Floating Production Storage and Offloading (FPSO) project. In one of the efforts to achieve its GHG emissions reduction targets, Petrobras is undertaking studies to assess the technical and economic viability of integrating post-combustion CO₂ capture units into its future offshore projects.

In an FPSO, the exhausting gases from the fuel combustion of the gas turbine generators (GTGs) can account from 60% to 80% of total greenhouse gas emissions. Therefore, capturing and appropriately storing the CO₂ contained in the exhausted gases represents a significant impact in the emissions of an FPSO.

The qualification of the CO₂ Capture Plant within the FPSO is part of the solution within a production development project, as it goes beyond the boundaries of the FPSO. For instance, the specification of the capture plant itself is dependent on the intended use of the captured CO₂. Moreover, meeting the required specification levels for O2 and H₂O content may require the incorporation of additional equipment. Notwithstanding the novelty of the application, Petrobras intends to:

• Identify and understand the limitations for offshore applications.

• Scale the solution for different scenarios.

• Identify metrics for CCUS such as CO₂ marginal abatement cost, electric demand, and heat and cold duties.

• Provide detailed specifications for the capture module in the project documentation, such as the Engineering, Procurement, and Construction (EPC) or Chartering documents.

With the specific aim of capturing and mitigating greenhouse gas emissions, there are currently not offshore commercially operational post-combustion CO₂ capture (PCCC) plants for natural gas worldwide. Petrobras' initiative could, therefore, contribute to understanding the limitations of the technology for the mentioned application and provide new and relevant insights for the future of offshore oil and gas production. This would enable lower CO₂ emission rates and pave the way for a more sustainable and efficient FPSO energy production process.