The potential of carbon capture technologies for shipboard application - A review of carbon capture technologies and their feasibility for the application onboard vessels

Abstract

The IMO’s Initial strategy on reduction of GHG emissions from ships defined the goal to reduce the total emissions from international shipping by 50 % in 2050, compared to the emissions of 2008. The majority of ships being built today and up to 2030 are expected to be equipped with combustion engines running on fossil fuels. The fact that vessels have an average scrappage age of 28 years, further highlights the problematical long-time dependence of shipping on fossil fuels. Therefore, carbon capture technology is considered as an option allowing the combustion of fossil fuels and still being able to reduce the emission of GHGs. This thesis is taking a top-down approach to identify carbon capture technologies which have been researched until today. The conducted literature review identifies several post- and pre-combustion capture systems as well as oxyfuel combustion as technologies to capture CO2 from fossil fuel combustion exhausts. Based on the knowledge retrieved from literature and expert interviews, a broad spectrum of carbon capture technologies is presented, including information on the process setup, current applications, costs, space requirements as well as specific advantages and drawbacks of each technology. Furthermore, the research conducted for the application of the identified technologies onboard has been reviewed and the findings are presented in a summarised form. To decide which of the identified technologies is the most promising for the application onboard, a comparative assessment is conducted, with specific regards to the constraints determined by the particulars of the onboard environment. The technology found to perform best in newbuilding as well as retrofit applications, is post-combustion absorption with aqueous ammonia as solvent. Although post-combustion carbon capture technology in general is found to be feasible for all ships, implications on the transport capacity and economy-of-scale factors show, that carbon capture technology might be more feasible for larger vessels.