Industry Guidelines for Setting the CO2 Specification in CCUS Chains

Abstract Impurities in captured CO2 can adversely affect the material integrity, operation and injectivity in CCUS chains and setting the CO2 specification requires an understanding of the impact of impurities across the whole chain. Carbon Capture, Utilisation and Storage (CCUS) is one of the key pathways towards a net-zero future and significant growth is required in this industry. However, limited literature is currently available which supports setting a CO2 specification considering the full CCUS value chain. A Joint Industry Project (JIP) was therefore formed to collate current knowledge surrounding impurities and to create guidelines to support industry in setting CO2 specifications for effective and economic CCUS chains. This paper discusses the guidelines, which can be downloaded from the JIP webpage [1]. The JIP comprised industry and research experts to provide a comprehensive and holistic understanding of the impact of impurities and to determine the required CO2 conditioning to meet safety, environmental, technical and operational requirements. As shown in Fig. 1, the JIP addressed a suite of Work Packages to cover the full value chain of CCUS, considering capture of CO2 from various industrial sources and transportation via different options through to permanent sequestration in geological storage. Additional foundation Work Packages including Thermodynamics, Reaction Chemistry and Materials & Corrosion were created to underpin the entire CCUS chain. Figure 1 JIP Work Packages [1] Each Work Package provides a comprehensive report where the current knowledge on the impact of impurities is given and opportunities for further research identified. The reports include information such as: A logical workflow methodology for setting a CO2 specification. Guidance on effective thermodynamic modelling of CO2 with impurities plus a comparison of the most advanced modelling methodologies against experimental data. Identification of potential chemical reactions which can lead to corrosion and/or solids deposition impacting material integrity and injectivity. Guidance for material selection and corrosion control in the presence of impurities. Review of impurity content on dispersion of released CO2. A review of CO2 capture and purification processes including a review of impurities on liquefaction. Impact of impurities on compression / pumping equipment design and operation. Discussion on the challenges of impurities on metering and sampling technology selection and calibration. Safe design and operation of pipeline and shipping transportation. Impact of impurities on injectivity, reservoir permeability and caprock integrity in saline and gas depleted reservoirs. A review of levelized cost of CO2 abatement methods and examples of impurity removal economics. As a suite of reports, these guidelines will support readers in their understanding of the impact of impurities and aid in the setting of a CO2 specification for CCUS projects.