Preliminary Design of a Cryogenic System with GM Cryocooler for Testing the Hydrogen Condensers of the Distillation Columns

The Experimental Pilot Plant for Tritium and Duterium Separation has been designed and built at the Rm. Valcea National Research and Development Institute for Cryogenics and Isotopic Technologies to separate deuterium and tritium from deuterated and tritiated water based on two combined processes: catalytic isotope exchange and cryogenic distillation. For this, additional experimental stands were developed for testing different components of the columns, such as the cold box, heat exchangers, condensers, and boilers. This paper presents the design of a new generation of fin condensers that avoids film condensation and allows the dropwise condensation mode. A small-scale cryogenic system equipped with a hydrogen liquefaction unit is presented as an alternative for condenser conductivity testing. The condenser is fixed on a hydrogen tank that is protected by a radiation shield and mounted inside a vacuum chamber. The proposed method is to continuously liquefy hydrogen using a two-stage Gifford McMahon 4K cycle cryocooler. A method for estimating the liquefaction rate was proposed and confirmed by the test results.