초록 ▼

In a cryogenic air distillation process for producing medium-to-high purity oxygen plus optional coproduct argon, a new process sequence results in more efficient distillations at reduced supply pressure and full O2 recovery. Reforming to FIG. 2, a minor stream of supply air is additionally compress

In a cryogenic air distillation process for producing medium-to-high purity oxygen plus optional coproduct argon, a new process sequence results in more efficient distillations at reduced supply pressure and full O2 recovery. Reforming to FIG. 2, a minor stream of supply air is additionally compressed by compander 204, cooled, and then reboils column 201 by total condensation in reboiler 205. The liquid air is split into two intermediate reflux streams, one for each column 201 and 202, valves 206 and 207, thereby improving the efficiency of both columns. The air condensing in 205 is somewhat hotter than that supplied to 202, due to its higher pressure, which permits a reduction in the main supply pressure.

대표청구항 ▼

A process for producing oxygen from a supply of compressed air by cryogenic fractional distillation comprising: (a) cooling and rectifying a major fraction of said supply air in a HP rectifier to nitrogen overhead product and kettle liquid bottom product; (b) distilling the kettle liquid in a low pr

A process for producing oxygen from a supply of compressed air by cryogenic fractional distillation comprising: (a) cooling and rectifying a major fraction of said supply air in a HP rectifier to nitrogen overhead product and kettle liquid bottom product; (b) distilling the kettle liquid in a low pressure nitrogen rejection column (LP column) to overhead waste nitrogen and oxygen bottom product; (c) additionally compressing a minor fraction of said supply air; (d) cooling said additionally compressed air and condensing it to liquid by exchanging latent heat with at least LP column bottom liquid in at least one reboiler, thereby providing bottom reboil to said LP column; (e) providing part of the liquefied additionally compressed air from step d) to an intermediate height of the HP rectifier as intermediate reflux therefor, and providing the remaining part to an intermediate height of the LP column as intermediate reflux therefor; and (f) evaporating said oxygen bottom product at a pressure no less than the LP column pressure and withdrawing the gaseous oxygen as product.