Concentration ofHe3by Thermal Diffusion

A thermal diffusion plant for the enrichment of ${\mathrm{He}}^3$ has been constructed consisting of cylindrical columns followed by a hot wire column. In the case of the cylindrical columns excellent agreement with the theory of Jones and Furry has been obtained. In the case of the hot wire column, discrepancies exist between the observed performance and that predicted by theory. Under continuous operating conditions it was possible to produce with the expenditure of 16.6 kw, 14 std. cc of helium per day having a ${\mathrm{He}}^3$/${\mathrm{He}}^4$ ratio of 0.0021 when well helium was used as a source of gas.