| abstract |
Procedure for obtaining oxygen and nitrogen, optionally, on the one hand, in liquid form and, on the other hand, in gaseous form, in which a part of the reheated pure gaseous nitrogen that comes from the separation stage is compressed, cooled and condensed by exchange with a liquid natural gas in re-evaporation, it is expanded, at least a part of the expanded liquid fraction is used to ensure the reflux of said separation stage and the evaporated fraction is combined with the nitrogen to be be compressed, prior to said compression, characterized in that nitrogen in liquid form and in gaseous form and oxygen are obtained at various pressure levels and that said part of the reheated pure gaseous nitrogen, together with a part of this nitrogen gas removed before the end of the reheating after condensation and prior to its expansion, it is subcooled by counter-current passage The fraction of the fraction evaporated in the course of said expansion is eventually recondensed by exchange with the fraction of pure liquid oxygen obtained in the separation tank, and is collected after sub-cooling with nitrogen at intermediate pressure. (Machine-translation by Google Translate, not legally binding) |