Popis: |
Hydrogen, under atmospheric pressure, becomes liquid at 20.3 K. The liquefaction is carried out by extracting of 4914 kJ/kg of heat. This liquefaction requires the use of some high level cryogenic technology whether to liquefy it or to keep it in the liquid state. In general, three processes are applied: Claude cycle, Brayton cycle and liquefaction by magnetocaloric effects (Magnetic Refrigeration). The present work aims at performing comparison between conventional liquefaction and magnetic liquefaction systems. It deals with a comparison between performances and energy consumption evaluated for the two systems at similar operating conditions. Precooled Claude liquefaction cycle has been considered for the first one. Here, energy and material balances has been performed by use of Aspen Hysys simulator. However, the second one is based on a multistage Active Magnetic Regenerator (AMR) cycles operating with real magnetic materials. A new simulation method has been proposed to use Aspen Hysys simulator for thermal analysis of the AMR liquefier. |