The energy transition is well underway with many countries and companies assessing options for CO2 sequestration. The CO2 value chain captures, transports, stores or utilises carbon dioxide from industrial sources. The value chain can include international shipping of CO2 as part of large volume transport and storage solutions. Traditional shipping of CO2 involves an intermediate storage solution (potentially located onshore) and a long pipeline to the injection site (potentially located offshore). Direct injection of CO2 is a novel solution involving sailing a vessel directly to a well site and thus removing intermediate storage and long distance pipelines. This paper will showcase the options available for direct injection and discuss the potential cost savings. Liquid CO2 (LCO2) can be directly injected using a floating storage injection unit, a floating injection unit, a tower loading unit or a catenary anchor leg mooring buoy. There is not a ‘one size fits all’ solution to direct LCO2 injection, and the chosen option requires careful project consideration: a key consideration is whether the project requires continuous injection into the well, or if intermittent injection is possible without imposing excessive stress on the wells during start-up and shut-down cycles. In addition, location-specific considerations, e.g., around wave height, water depth and power sources must be made in order to drive concept selection. Direct offshore injection has the potential to save significant capital and operational expenditure associated with intermediate storage and pipelines – unlocking a critical pathway for reducing the cost of large-scale decarbonisation. This paper investigates direct injection options through a cost benefit analysis, demonstrating potential solutions to improve the value of carbon capture and storage projects.
Peace et al. (Thu,) studied this question.