| 초록 |
Hydrogen is an important clean energy carrier that can promote GHG-less energy production. However, long-time storage and long-distance transportation of hydrogen is a challenging issue given its low energy density. Liquefaction is a worthwhile approach to enhance energy density; however, it is an energy and cost-intensive technique. Commercial hydrogen liquefaction processes report specific energy consumption (SEC) in the range of 12-15 kWh/kg with an exergy efficiency of 19-23%. This study presents an energy-efficient and cost-effective process configuration to produce liquid hydrogen through step-wise cooling with subsequent ortho to para conversion. The proposed process shows an SEC of 7.62 kWh/kg with 31.4% exergy efficiency. Additionally, the economic evaluation shows total equipment cost and total annualized cost as 12.3 m$ and 24.2 m$/y, respectively. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (2021R1A2C1092152) and by the Priority Research Centers Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2014R1A6A1031189). |
