Conceptual Design of Metal Hydride Cartridges with Systematic Alloy Selection and Sizing Guidelines for Boil-Off-Gas Recovery from Liquid Hydrogen

Hydrogen has huge potential for sustainable future industries, but the formation of hydrogen boil-off gas (BOG) is a main drawback of liquid hydrogen (LH2) applications as BOG venting raises safety issues and leads to significant hydrogen loss. A promising approach for BOG recovery is a system with exchangeable cartridges filled with metal hydride (MH). Previous studies focus on the macroscopic level of the interaction between the cartridges with the boil-off sources and the consumers. A detailed investigation of the cartridge design remains necessary to assess the potential of this novel BOG recovery system. This study elaborates design concepts for the individual cartridge. A thorough material selection for suitable MH alloys is conducted and requirements for the cartridge design are derived. The key design features of the cartridges are determined and summarized in a morphological box. Four explicit design concepts are elaborated and illustrated. These results provide the baseline for upcoming studies to explicitly design and manufacture an MH cartridge demonstrator for testing, assisting the transformation to an even more sustainable LH2 industry.