| 摘要 |
<p>S P E C I F I C A T I O N TO ALL WHOM IT MAY CONCERN: BE IT KNOWN THAT I, RONALD DENIS OPENSHAW, a British citizen, of 8 Beech Crescent, Poynton, Stockport, Cheshire, United Kingdom, have invented certain new and useful improvements in IMPROVEMENTS IN THE PRODUCTION OF PURE NITROGEN of which the following is a description. A process and apparatus for the production of nitrogen from air by the cryogenic fractionation of the air at superatmospheric pressure and which permits the production of variable quantities of nitrogen from a constant supply of air at superatmospheric pressure by periodically distilling less than all of the air which is supplied at superatmospheric pressure and work expanding a stream of air at superatmospheric pressure provided from the balance of said supply whereby to produce additional refrigeration for the process, and recovering condensed nitrogen vapour thereby formed in excess of that required for reflux.</p> |
