Design and Economic Analysis of Liquid CO₂ Injection System

In order to curtail the global warming, carbon capture and storage (CCS) has been on the strategies list as one of the potential technologies. Shipping of pressurized CO2 in the liquid phase offers a flexible and economical solution for the transportation of large quantities from the capture site to the storage location. This study presents the design for unloading and injection of liquid CO2 available from the ship-based transport into the reservoir. This study proposed a CO2 injection design in order to explore process improvements compared to the base case design. The proposed design offers less energy consumption, improved operational safety and reduced unit injection cost compared to the base case design. Commercial process simulator, Aspen HYSYS has been used to simulate the CO2 injection system for deciding the key process variables. Literature has widely reported the CO2 shipping conditions of -52 °C and 7 – 8 bara in contrast to the current CO2 shipping practice at -20 °C and 20 bara. The impact of CO2 shipping thermodynamic conditions has been investigated on the injection system in terms of process performance and economics. Finally, a sensitivity analysis has been done in order to investigate the effect of some assumed variables on the process performance.