Investigation of the energy and exergy performance of a hydrogen liquefaction cycle employing LNG and improved Joule-Brayton cycle

The use of hydrogen as a clean fuel has gained the attention of many scientists due to the energy issues and environmental pollution caused by fossil fuels. A key requirement for expanding hydrogen use is the investigation and thermodynamic analysis of the liquefaction cycle, which includes examining various hydrogen liquefaction cycles during pre-cooling and cryogenic cooling. Analyzed cycle is a liquefaction process that utilizes advanced cascade Joule-Brayton (J-B) refrigeration cycles and a dual-pressure organic Rankine cycle, assisted by LNG regasification. Simulations and analyzes were conducted using Aspen HYSYS V۱۲. The results showed that in the cycle, over ۵۰% of the input exergy is lost during the cryogenic cooling stage. The value of SEC, COP and EXE cycle is ۶.۶۱۸ kWh/kgLH۲, ۰.۱۹۸۸۴ and ۴۵.۷۹۷% respectively. The net output power of the Rankine cycle is ۴۵۸.۸۲ kW, which can be used to feed other parts of the hydrogen liquefaction process. Also, the results showed that in the pre-cooling process, the amount of useful exergy is ۶۱.۲۱%, which uses ۲۲.۷۳% of the input exergy in a better way compared to the existing cycles.

کلیدواژه ها:

Hydrogen liquefaction ، Joule-Brayton cycle ، LNG ، Aspen HYSYS