2018, Volume 21, Issue 2
The technological chain of enrichment of 3He
1 Institut für Luft- und Kältetechnik gemeinnützige Gesellschaft mbH, Hauptbereich Kryotechnik und Tieftemperaturphysik, Bertolt-Brecht-Allee 20, 01309 Dresden, Germany
2 Bauman 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.
Separation of Helium Isotopes by Rectification and Thermo-Osmosis
Journal of Experimental Theoretical Physics (U.S.S.R.) 32(5):1001
3He Separation by a Heat Flux in Liquid Helium II
Physical Review, 73(3):256-257, Published 1 February 1948
Experimental principles and methods below 1 K
Helsinki Univ. of Technology, Finland
Concentration of 3He by Thermal Diffusion
Physical Review, 74(8):946-949, Published 15 October 1948
Applied Nuclear Physics
Published by John Wiley & Sons, New York
3He isotope, natural helium mixture, low temperature filtration, cryostatting
Tag search 3He isotope natural helium mixture low temperature filtration cryostatting