ClassNK has issued an Approval in Principle for the design of a liquefied carbon dioxide carrier intended to support a floating offshore carbon capture and storage injection facility.

The vessel's design is intended to service a Socket SPAR unit, a floating injection system considered for deployment in deep-water environments, particularly in areas where seabed pipelines for CO2 storage are not feasible.

ClassNK stated that the certification confirms the feasibility of the carrier's design from regulatory and safety perspectives.

This concept is part of an environmentally friendly CCS demonstration project in Japan, which is evaluating offshore injection solutions suitable for the country's deep-sea and steep seabed conditions.

The design for the CO2 carrier was developed by Shin Kurushima Sanoyas Shipbuilding Co., Ltd., commissioned by project alliance member Uyeno Transtech.

ClassNK indicated that it reviewed the vessel design against its rules for steel ship construction, including compliance with relevant sections of the International Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk, which applies to ships transporting liquefied gases like CO2 and LNG.

The approval also included verification of tests related to CO2 handling, assessing risks such as the potential clogging of safety relief valves and piping systems due to CO2 solidifying into dry ice under certain conditions.

As part of a broader CCS development initiative, ClassNK had previously granted an Approval in Principle for the Socket SPAR concept in 2023.