Cryogenic Rectification system for producing lower purity gaseous oxygen and high purity oxygen
AssigneePraxair Technology, Inc.
InventorsHenry E. Howard, Dante P. Bonaquist
Life of this patent
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Abstract
A cryogenic rectification system for producing lower purity gaseous oxygen and high purity oxygen employing a double column and an auxiliary column which upgrades lower pressure column bottom liquid or processes higher pressure column kettle liquid.
Claims15
A cryogenic rectification method for the production of lower purity gaseous oxygen and high purity oxygen comprising:
- (A) passing feed air into a higher pressure column and separating the feed air within the higher pressure column by cryogenic rectification into oxygen-enriched liquid and into nitrogen-enriched fluid;
- (B) passing oxygen-enriched liquid and a first portion of the nitrogen-enriched fluid into a lower pressure column and producing oxygen-richer liquid within the lower pressure column;
- (C) passing oxygen-richer liquid from the lower pressure column into an auxiliary column and producing further oxygen-richer liquid within the auxiliary column;
- (D) at least partially vaporizing the further oxygen-richer liquid by indirect heat exchange with a second portion of the nitrogen-enriched fluid and producing lower purity gaseous oxygen and high purity oxygen within the auxiliary column;
- and
- (E) recovering lower purity gaseous oxygen and high purity oxygen from the auxiliary column.
A cryogenic rectification apparatus for the production of lower purity gaseous oxygen and high purity oxygen comprising:
- (A) a double column comprising a first column and a second column and means for passing feed air into the first column;
- (B) an auxiliary column comprising a reboiler and means for passing fluid from the upper portion of the first column into the reboiler;
- (C) means for passing fluid from the first column into the second column;
- (D) means for passing fluid from the lower portion of the second column into the auxiliary column;
- and
- (E) means for recovering product from the upper portion and means for recovering product from the lower portion of the auxiliary column.
A cryogenic rectification method for the production of lower purity gaseous oxygen and high purity oxygen comprising:
- (A) passing feed air into a higher pressure column and separating the feed air within the higher pressure column by cryogenic rectification into oxygen-enriched liquid and into nitrogen-enriched fluid;
- (B) passing nitrogen-enriched fluid and a first portion of the oxygen-enriched liquid into a lower pressure column and producing lower purity gaseous oxygen within the lower pressure column;
- (C) passing a second portion of the oxygen-enriched liquid from the higher pressure column into an auxiliary column and producing higher purity oxygen within the auxiliary column;
- (D) recovering lower purity gaseous oxygen from the lower pressure column;
- and
- (E) recovering high purity oxygen from the auxiliary column.
A cryogenic rectification apparatus for the production of lower purity gaseous oxygen and high purity oxygen comprising:
- (A) a double column comprising a first column and a second column and means for passing feed air into the first column;
- (B) an auxiliary column and means for passing fluid from the lower portion of the first column into the auxiliary column;
- (C) means for passing fluid from the first column into the second column;
- (D) means for recovering product from the second column;
- and
- (E) means for recovering product from the auxiliary column.
A cryogenic rectification method for the production of lower purity gaseous oxygen and high purity oxygen comprising:
- (A) passing feed air into a higher pressure column and separating the feed air within the higher pressure column by cryogenic rectification into oxygen-enriched liquid and into nitrogen-enriched fluid;
- (B) passing oxygen-enriched liquid and nitrogen-enriched fluid into a lower pressure column and producing oxygen-richer liquid within the lower pressure column;
- (C) passing oxygen-richer liquid from the lower pressure column into an auxiliary column operating at a pressure greater than that of the lower pressure column, and producing further oxygen-richer liquid within the auxiliary column;
- (D) at least partially vaporizing the further oxygen-richer liquid and producing lower purity gaseous oxygen and high purity oxygen within the auxiliary column;
- and
- (E) recovering lower purity gaseous oxygen and high purity oxygen from the auxiliary column.
Dependencies are inferred from the claim text.