With the increasing severity of climate change, Carbon Capture, Utilization, and Storage (CCUS) technology has become essential for reducing atmospheric CO₂. Marine carbon sequestration, which stores CO₂ in seabed geological structures, offers advantages such as large storage capacity and high stability. Cryogenic hoses are critical for the ship-to-ship transfer of liquid CO₂ from transportation vessels to offshore carbon sequestration platforms, but their design methods and mechanical analysis remain inadequately understood. This study reviews existing cryogenic hose designs, including reinforced corrugated hoses, vacuum-insulated hoses, and composite hoses, to assess their suitability for liquid CO₂ transfer. Based on CO₂’s physicochemical properties, a conceptual composite hose structure is proposed, featuring a double-spring-supported internal composite hose, thermal insulation layer, and outer sheath. Practical recommendations for material selection, corrosion prevention, and monitoring strategies are provided to improve flexibility, pressure resistance, and thermal insulation, enabling reliable long-distance tandem transfer. A mechanical analysis framework is developed to evaluate structural performance under conditions including mechanical loads, thermal stress, and dynamic responses. This manuscript includes an introduction to the background, the methodology for data collection, a review of existing designs, an analysis of CO₂ characteristics, the proposed design methods, the mechanical analysis framework, a discussion of challenges, and the conclusions.

This study employs a combined approach of theoretical calculation and numerical simulation to systematically optimize the impeller of a turbine expander, the core component of a 10-ton/day hydrogen liquefaction system. First, based on thermodynamic analysis and one-dimensional calculations, a three-factor four-level orthogonal experiment optimizes the parameters of reaction degree, radius ratio, and blade height ratio. Building upon this foundation, the influence of two-dimensional meridional profiles on impeller efficiency is investigated to establish design criteria. Subsequently, the effects of three-dimensional parameters including tip clearance, blade count, and blade thickness on performance are analyzed. Finally, the impact of rotational speed and flow rate on efficiency is explored, identifying high-efficiency operational ranges. Through multi-parameter collaborative optimization, an impeller configuration achieving low outlet temperature (53.67 K) and high efficiency (about 93.6%) is obtained, providing critical references for designing high-efficiency turbine expanders in hydrogen liquefaction systems.

In this study, we perform molecular dynamics simulations to investigate the desublimation of carbon dioxide (CO₂) on hydrophilic and hydrophobic surfaces with nanostructures. The results reveal that the presence of surface nanostructures substantially reduces the temperature threshold for CO₂ desublimation relative to that observed on smooth surfaces. On hydrophilic surfaces, the adsorption layer is found to be considerably thicker, and the surface topography disrupts the spatial ordering of CO₂ molecules at the liquid–solid interface, delaying nucleation onset by 65.68% relative to the smooth surface in the representative trajectory. In contrast, the introduction of nanostructures effectively increases the heat transfer area on hydrophobic surfaces, thereby promoting CO₂ condensation and accelerating the overall desublimation process, with a 42.86% reduction in nucleation onset time on structured surfaces. These findings suggest that the judicious selection of surface wettability and morphology enables tunable control over both condensation and nucleation kinetics, which holds practical implications for the design of efficient carbon capture systems.