New CO2 Liquefaction Method will be “Game Changer”

JX Nippon Oil & Gas Exploration Corporation, NYK and NYK affiliate Knutsen NYK Carbon Carriers (KNCC) have demonstrated a new CO2 liquefaction method that the partners say is a breakthrough for the carbon capture and storage (CCS) industry.

The three companies have devised the CO2 liquefaction process based on the isenthalpic expansion cooling and liquefaction process which takes advantage of the temperature drop caused by depressurizing the captured CO2 to form a liquefied CO2 suitable for marine transport.

In principle, the liquefaction efficiency of the process is equal to or higher than that of conventional liquefaction conditions and methods, and energy reductions of up to 20% are expected, say the partners. In addition, the equipment required is simpler and more compact than conventional liquefaction methods, and modularization and floating systems can also be considered, which is expected to contribute to reducing the cost and site area of CO2 liquefaction facilities in the CCS and CCUS value chain.

The demonstration was conducted at KNCC's demonstration facility in Norway. Through the experiment, CO2, which replicated the conditions under which it was gathered and transported by pipeline, was successfully liquefied and transferred to KNCC’s proprietary LCO2-EP Cargo Tank designed to transport LCO2 at ambient temperatures and elevated pressures (0 to 10 degC / 34 to 45 barG).

The companies have concluded that the technology devised in this Process has achieved a technology readiness level (TRL) of 6.

Oliver Hagen-Smith, CEO, KNCC, said: “The developed liquefaction method will be a game changer for the CCS industry as it enables seamless liquefaction of CO2 in the export process. Minimizing OPEX and the area required for liquefaction, but also in specific cases removing the need for onshore storage, is crucial in the development of CCS value chains. The developed liquefaction process along with the LCO2-EP Cargo Tanks again proves that KNCC and its partners provide optimized economical, flexible and optionality in solutions to the industry.”