As carbon capture and storage is set to play an important role in the global efforts to reduce greenhouse gas emissions there will be a need to transport CO2 in liquid form from the point of capture to the point of disposal
Maersk Tankers, Hyundai Heavy Industries (HHI) and Det Norske Veritas have agreed to collaborate on the design and risk assessment of tankers for shipping CO2. This collaboration complements the existing partnership Maersk Tankers has already formed with Maersk Oil and Finnish utilities Fortum and Teollisuuden Voima (TVO), aimed at developing a joint carbon emissions abatement project in the area of carbon capture and storage (CCS).
“Shipping CO2 in tanker vessels is a cost effective and flexible way to get it from power plants to offshore storage sites, making it a suitable solution for large CO2 emission sources such as coal-fired power plants, especially in the emerging phase of CCS,” said Anders Schulze, head of CO2 shipping, Maersk Tankers.
Maersk Tankers and HHI have produced the initial blueprints for vessels capable of transporting CO2 from emission sources to storage sites. The vessels will be semi-pressurised and semi-refrigerated, keeping the CO2 in liquid form. The designs are a result of many years experience in the transportation of liquefied petrochemicals and natural gas, and in accordance with global standards.
“The further development of the CO2 carrier design will focus on the safety and environmental requirements while emphasising the high energy efficiency of the vessels,” said Jae Keun Ha, senior vice president, HHI. “Technical co-operation with Maersk Tankers and DNV demonstrates HHI’s policy of pursuing new technology and finding solutions to the environmental issues in the shipbuilding segment.”
DNV will provide feasibility studies, risk identification and general support for compliance with applicable class rules and the current Gas Carrier Code. These tasks will also include evaluations and support to ensure that the vessel is fit for purpose and fits into the specific CCS chain.
“The overall technical features of these vessels have similarities with LPG carriers and offshore shuttle tankers,” said Jan Koren, DNV’s segment director for tankers. “Many of the applicable safety standards to be applied are therefore basically well known. Studies will, however, have to be carried out to ensure that all features and specialities have been adequately addressed and that the vessels interface with the rest of the CCS chain.”
Another classification society with considerable experience in the tanker sector is also interested in the idea of CO2 shipping. Bureau Veritas believes that although renewable energy and nuclear power are being promoted to satisfy energy needs and reduce CO2 emissions generated by the use of fossil fuels, for the foreseeable future fossil fuels will continue to provide the majority of the energy required.
In view of this, the idea of the capture and permanent storage of CO2 in geological formations such as depleted oil and gas fields is currently of interest to the shipping industry. Due to its greater flexibility, shorter time to market and reduced capital expenditure compared with pipelines, the option of shipping CO2 has key advantages, especially in the early phases of any project. However, although technically feasible, prior to considering any project for the shipping of CO2, particularly in the volumes that will be required for CCS purposes, the unusual characteristics of CO2 need to be clearly understood and addressed. For instance, the density and the cargo carriage conditions of the CO2 to be transported will have a significant impact on the type and design of the gas carrier itself, whilst the cleanliness of the waste CO2 will affect the materials chosen for the construction of the cargo tanks, pipework and associated machinery.
Challenges such as the cargo containment system, the ship arrangement and the cargo handling, loading and off-loading arrangements need to be considered and it is in these fields particularly that BV is now focusing its efforts and can provide valuable feedback and assistance to projects being studied.
Purpose built CO2 carrier designs will need to overcome these challenges to comply with current rules and regulations. BV has experience in this area that it gained during the pioneering conversion and ship building projects, for Yara Gas and Anthony Veder respectively, in the 1990s.
According to BV, extensive experience and knowledge in the field of gas carrier design and classification, in conjunction with work already performed in the field of CO2 carriers, puts it in a unique position to be able to contribute to overcome these technical challenges. It also realises that major hurdles in connection with finance; legislation and infrastructure also need to be overcome for CO2 shipping to become a reality. MP