Progress of Cryogenics and Isotopes Separation


The National Conference with international participation on New Cryogenic and Isotope Technologies for Energy and Environment - EnergEn 2018 is organized by the National Research-Development Institute for Cryogenic and Isotopic Technologies - ICSI Rm. Valcea with the scientific participation of the University of Pitesti and the University of Craiova and will be held at Baile Govora, in 2018.




Petar Dalakov1*, Maxim Kupriyanov2, Jürgen Klier1

1Institut für Luft- und Kältetechnik gemeinnützige Gesellschaft mbH, Hauptbereich Kryotechnik und Tieftemperaturphysik, Bertolt-Brecht-Allee 20, 01309 Dresden, Germany; 2Bauman Moscow State Technical University, Moscow, 105005, Russia




Currently, the most suitable raw material for the production of 3He is natural helium, which is a natural mixture of 4He and 3He isotopes. Natural helium is produced at large air separation plants. The concentration of 3He in natural helium is only 1.4 ppm, but this is about ten times higher than the concentration of 3He in helium from natural gas fields.

The use of traditional technologies for the enrichment of 3He to high concentrations is practically impossible because of the meager concentration of 3He at the initial stage. Therefore, in order to enrich 3He in the first stage, it is better to use filtration at a temperature level below the lambda transition temperature Tλ of 4He, at which the concentration of the 3He isotope can be increased up to 103 ... 104 ppm. After the filtration process, a rectification or adsorption can be used to further enrichment of 3He.

A technological chain for an enrichment of the isotope of 3He from the initial low concentration with several ppm to high concentrations up to 95 ... 97 vol.% of 3He, as well as the main economic indicators of the system is reported in this paper. The proposed technological chain consists of two stages. In the first stage 3He is preliminarily enriched (filtered) at a temperature below Tλ. The second stage uses a distillation column operating at a temperature level of 1.3 ... 3.0 K.

Keywords: 3He isotope, natural helium mixture, low temperature filtration, cryostatting.


*Corresponding authors: Petar Dalakov, E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it