Patent ID: 11879685
Assignee: L'AIR LIQUIDE, SOCIETE ANONYME POUR L'ETUDE ET L'EXPLOITATION DES PROCEDES GEORGES CLAUDE
Field: Chemical engineering (Chemistry)
Classification: CPC F | IPC F

Claim 2:
3. The high-purity oxygen production system according to claim 1, wherein the at least one high-purity oxygen rectification column further comprises:
a first oxygen rectification column having: a first oxygen rectification column rectification portion to which the second rectification liquid drawn from the low-pressure column bottom is introduced at an intermediate portion thereof or therebelow, a first oxygen rectification column bottom arranged below the first oxygen rectification column rectification portion, and a first oxygen rectification column top arranged above the first rectification column rectification portion;
a first oxygen evaporator arranged inside or below the first oxygen rectification column bottom, the first oxygen evaporator causing evaporation of a rectification liquid falling from the first oxygen rectification column rectification portion and the second rectification liquid which has been introduced;
a first oxygen condenser arranged inside or above the first oxygen rectification column top, wherein a first oxygen rectification gas drawn from an upper portion of the first oxygen rectification column rectification portion is cooled and liquefied by first liquid nitrogen condensed in the first oxygen evaporator, and is returned to the first oxygen rectification column rectification portion;
a second oxygen rectification column having a second oxygen rectification column bottom, a second oxygen rectification column rectification portion arranged above the second oxygen rectification column bottom, and a second oxygen rectification column top arranged above the second oxygen rectification column rectification portion;
a second oxygen evaporator arranged inside or below the second oxygen rectification column bottom, the second oxygen evaporator causing evaporation of a rectification liquid falling from the second oxygen rectification column rectification portion; and
a second oxygen condenser arranged inside or above the second oxygen rectification column top, wherein the second oxygen condenser is configured to cool and liquefy a second oxygen rectification gas drawn from an upper portion of the second oxygen rectification column rectification portion by means of second liquid nitrogen sent to the second oxygen condenser, and returns the cooled and liquefied gas to the second oxygen rectification column rectification portion;
wherein the nitrogen heat exchanger is configured to receive a nitrogen-rich gas drawn from a space above the second oxygen condenser in the second oxygen rectification column top;
wherein the nitrogen compressor is configured to compress the nitrogen-rich gas drawn from the space above the second oxygen condenser in the second oxygen rectification column top;
wherein the high-purity oxygen production apparatus further comprises:
a line configured to recirculate a compressed nitrogen-rich gas compressed in the nitrogen compressor to the nitrogen heat exchanger, and introducing the nitrogen-rich gas to a space below the first oxygen evaporator in the first oxygen rectification column bottom; and
a branch line which branches from the line and is configured to introduce the nitrogen-rich gas to a space below the second oxygen evaporator in the second oxygen rectification column bottom.