Techno-economic analysis on the performance of hydrogen adsorbents in the vacuum layer of cryogenic liquid storage tank

Abstract

The increasing demands for cryogenic liquid fuels pose serious challenges to storage and transportation technology. Hydrogen leakage occurs in cryogenic liquid storage tanks since hydrogen molecules can slowly diffuse through microscopic pores, which greatly weakens the performance of vacuum insulation layer. Various materials with high adsorption capacity have been developed to inhibit this phenomenon while few research focuses on the working performance inside tanks, which leads to the excessive dosage of adsorbents. This work aims to analyze the adsorption performance and economic benefits of hydrogen adsorbents in liquid hydrogen (LH) and liquid natural gas (LNG) tank, respectively. The results indicate that silver molecular sieve (SMS) is a cost-effective adsorbent in the long-term cryogenic liquid storage. LNG tank needs more ambient temperature adsorbents to maintain a similar performance to LH tank. For a 250 m³ LH tank, the optimal mass by using SMS ranges from 700 g to 800 g while a dosage of 900–1000 g is the best for a 250 m³ LNG tank. The excessive use of hydrogen adsorbents can't effectively improve the performance of cryogenic liquid storage tanks. These research findings may help the future vacuum maintenance in cryogenic liquid storage tanks.