A graphical approach for pinch-based source-sink matching and sensitivity analysis in carbon capture and storage systems

Carbon capture and storage (CCS) is regarded as an important interim technology for the reduction of carbon dioxide (CO₂) emissions from large industrial facilities such as power plants and refineries. CCS involves capture of concentrated CO₂ streams from point sources (industrial flue gases), followed by subsequent secure storage in an appropriate natural reservoir. Such reservoirs include various geological formations such as depleted oil or gas wells, inaccessible coal seams, and saline aquifers. In practice, such storage sites will have limitations on both CO₂ storage capacity and injection rate, subject to geological characteristics. In this work, a graphical approach is proposed for matching multiple CO₂ sources and storage sites (sinks) optimally within a predefined geographical region. The technique is developed on the basis of analogies with existing graphical pinch analysis approaches for the synthesis of industrial resource conservation networks (RCNs). Generalized principles for optimal CO₂ source-sink matching based on pinch analysis insights are discussed in this work. In addition, sensitivity of the system to the uncertainties that occur in CCS planning (e.g., variation of actual injectivity and capacity as well as options for increase or decrease of source lifetime) is considered. Realistic case studies are shown to illustrate these various aspects of the methodology.