Patent ID: 11933539
Assignee: PRAXAIR TECHNOLOGY, INC.
Field: Chemical engineering (Chemistry)
Classification: CPC F | IPC F

Claim 3:
4. The oxygen, argon and nitrogen producing air separation unit of claim 1, wherein:
the argon condensing arrangement comprises a first argon condenser configured for condensing a first portion of the argon-rich vapor stream from the argon column against the oxygen containing condensing medium from the higher pressure column or lower pressure column and a second argon condenser configured for condensing a second portion of the argon-rich vapor stream from the argon column against the oxygen containing condensing medium from the higher pressure column or lower pressure column; and
wherein the second portion of the boil-off vapor stream to be recycled is a first boil-off vapor stream exiting the first argon condenser and the first portion of the boil-off vapor stream to be returned to the lower pressure column is a second boil-off vapor stream exiting the second argon condenser.