The FSIU would be able to receive LCO2 transported at low pressure, store, and inject it into subsea wells at high pressure for permanent sequestration, which eliminates the need for an onshore LCO2 receiving plant and pipeline to injection wells. The unit is engineered for a maximum CO2 injection capacity of 10 million tonnes per annum (MTPA), with a minimum total tank storage capacity of 100,000m³.
Arata Kamishohara, VP Business and Project Development at MODEC, noted, “While this FSIU is a new concept, each component on the unit is not necessarily new to MODEC. MODEC has experience of CO2 injection (removed from pre-combustion produced gas) and dual (oil) offloading system. All the utility systems are similar to what we do on FPSOs every day."
"We collaborated with MOL, who cover the transportation portion of CCUS value chain, for interfaces between LCO2 carriers and the FSIU. With this, we are planning to achieve $5/tCO2 or less, which I don’t think is a stretch target.”
To support uninterrupted injection operations, the FSIU will feature both tandem loading at the aft and simultaneous side-by-side loading at the midship port side, enabling flexible and efficient LCO2 transfer from carriers, up to 90,000 m³ capacity (tandem) and up to 50,000 m³ (side-by-side).
The FSIU hull was developed in collaboration with Mitsubishi Shipbuilding Co. Ltd. (MSB), while the mooring system incorporates a SOFEC External Turret to allow dual loading operation as well as station keeping in non-directional environments as often found in Southeast Asia. The FSIU will also be equipped with diesel engine generators integrated with a carbon capture system on the topside, minimizing operational CO2 emissions.
This concept was developed in collaboration with Mitsui OSK Lines Ltd. (MOL), using their experience and market position with LCO2 carriers and proven methods of safe storage, transport and offloading.
By serving as an offshore storage and injection hub, the FSIU enables the sequestration of CO2 into qualified reservoirs. By offering large-scale, flexible, and reliable offshore CO2 storage, the solution supports the global transition to low-carbon energy.
MODEC LCO2FSIU, showing dual offloading to MOL LCO2 Carriers
MODEC said it considers this AiP as further demonstration of a floating solution for alternative energy production and will "continue to strive to refine and mature this concept to address the key challenges for commercialization identified during this development."