Innovative Solution for Optimal Heat Exchanger Application for the World’s Largest Offshore CCS Project: Addressing the Unique Properties of CO2

Abstract One of the significant challenges in large-scale Carbon Capture and Storage (CCS) projects is the efficient management of heat transfer, particularly in offshore environments where space and weight constraints complicate equipment selection. The purpose of this paper is to present a detailed study of heat exchanger application in high CO2 service, specifically focusing on aftercoolers in the compression train of the world’s largest offshore CCS project. The paper identifies key decision factors in the selection and design of heat exchangers for CO2 compression, considering the unique thermophysical properties of CO2, such as high density in the supercritical state, potential corrosivity, and the risk of freezing due to Joule-Thomson expansion. Using process simulation tools such as Aspen HYSYS and thermal design via HTRI, three main heat exchanger technologies—Shell-and-Tube (STHE), Printed Circuit Heat Exchanger (PCHE), and Air-Cooled Heat Exchanger (ACHE)—were evaluated against criteria such as pressure regime, thermal efficiency, weight, footprint, and operational reliability. This paper further discusses real-world fabrication and implementation challenges faced during the project, including compliance with ASME standards, high-pressure testing, and enhanced non-destructive testing (NDT) requirements. The outcome is a practical framework for selecting heat exchangers in CCS projects, emphasizing best practices, lessons learned, and the need for continued innovation in this field.