South Korean classification society Korean Register (KR) has issued Approval in Principle for a large liquefied natural gas-fuelled carbon dioxide (LCO2) carrier design on which it collaborated with compatriot Hyundai Heavy Industries.

Busan-headquartered KR and Hyundai undertook a joint development project to develop 40,000 cubic metre LCO2 carriers fuelled with LNG. Hyundai performed the basic and structural design of the carrier, while KR verified the safety and conformity of the design reviewing the class rules and international conventions.

The resulting concept design has now been awarded AIP by KR.

Carbon capture and storage projects are gaining traction globally as a means to achieving carbon neutrality and this has led to increased demand for technology for LCO2 carriers which can safely transport carbon dioxide captured in the supply chain.

Transporting CO2 in a liquid state requires a pressure C-Type cargo tank capable of withstanding a high vapour pressure of more than five atmospheres or greater, noted KR.

However, this type of cargo tank is usually employed on smaller carriers and there are technical difficulties in scaling up the size of the tank to meet the market need to transfer larger amounts of CO2 to storage facilities.

High specific gravity of liquefied carbon dioxide

“In addition, the tanks and supporting structures of LCO2 carriers must be designed with the greatest care because of the high specific gravity of liquefied CO2,” said KR.

One of the main aims of the joint development project was to explore the economic feasibility of large pressure-type CO2 storage tanks. To increase the size of the CO2 storage tanks, special materials with low-temperature and high-tensile need to be used instead of ordinary steel, which makes it challenging to control the thickness and weight of the tanks.

A KR official commented: “This AIP is a significant achievement, bringing the commercialisation of large LCO2 carrier technology even closer.

“KR will continue to support the industry’s work to develop CO2 capture, storage and burial-related technologies, while proactively working to address the industry-wide challenge of decarbonisation.”

The LCO2 carrier design is capable of storing up to 40,000 cubic metres of carbon dioxide using a type C pressure tank made of existing low-temperature and high-tensile materials. An LNG fuel propulsion system has been installed, ensuring low-carbon emissions during the carrier’s operation.

The safety of the carrier’s cargo hold, cargo tank and supporting structure was verified and approved using KR’s SeaTrust-HullScan software solution which was developed in house.