Conceptual Design of Profitable and Emission-Free Maritime Transportation

Rising anthropogenic CO₂ emissions and global temperature have been great concerns in the world. Maritime shipping represents a large part of CO₂ emissions from anthropogenic sources. This paper has developed a novel conceptual design of profitable and emission-free maritime transportation with an inherent carbon capture process to produce the pipeline-grade CO₂ product. It employs liquid natural gas (LNG) and air as the major feeds, and retrofits and installs two industrial process subsystems in the ship including (i) an air separation unit (ASU), and (ii) an Allam-cycle power plant (ACPP). Through optimally integrating energy/material streams among two subsystems, this new design can simultaneously produce electricity to empower the ship, pure N₂, and pipeline-ready CO₂ products efficiently and effectively through eco-friendly manufacturing ways without CO₂ and NOx emissions. The newly proposed design has been modeled and examined through a commercial simulator, and its exciting economic and environmental performances have also been evaluated and demonstrated compared with traditional maritime transportation. The study has significant potential with salient economic, environmental, and societal benefits, which could be further optimized in the future in the maritime shipping field.