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US 12,492,863 B2Granted
Process and plant for low-temperature separation of air
AssigneeLinde Aktiengesellschaft
InventorDimitri Golubev
Life of this patent
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Abstract
Described herein is a process for low-temperature separation of air, in which an air separation plant having a first rectification column and a second rectification column is used, the first rectification column being supplied with cooled compressed air and the second rectification column being supplied with liquid from the first rectification column or liquid formed herefrom. In a first condenser-evaporator, head gas from the first rectification column is condensed and liquid from the second rectification column, or liquid formed herefrom, is evaporated, thereby producing a first evaporation product.
Claims19
A process for the low-temperature separation of air using an air separation plant having a first rectification column and a second rectification column, said process comprising:
- operating the first rectification column at a pressure level of 9 to 13.5 bar and operating the second rectification column at a pressure level of 5.5 to 8.5 bar,
- supplying the first rectification column with cooled compressed air and supplying the second rectification column with liquid from the first rectification column or liquid formed herefrom,
- condensing a first portion of head gas from the first rectification column in a first condenser-evaporator and evaporating liquid from the second rectification column or liquid formed herefrom in the first condenser-evaporator to produce a first evaporation product,
- condensing head gas from the second rectification column in a second condenser-evaporator and evaporating further liquid from the second rectification column or liquid formed herefrom in the second condenser-evaporator to produce a second evaporation product,
- decompressing and heating a first portion of the second evaporation product, and removing resultant decompressed, heated first portion of the second evaporation product from the process, and
- removing a second portion of the head gas from the first rectification column from the process as a pure nitrogen product,
- wherein a third rectification column, operated at a pressure level of 1.1 to 2.5 bar, is also used in the process, and said process further comprises:
- condensing in a third condenser-evaporator a second portion of the second evaporation product and evaporating sump liquid from the third rectification column or liquid formed herefrom in the third condenser-evaporator to produce a third evaporation product,
- supplying at least part of the second portion of the second evaporation product condensed in the third condenser-evaporator to the third rectification column,
- supplying the third rectification column with non-evaporated further liquid from the second rectification column or liquid formed herefrom, and
- internally compressing and removing from the process further sump liquid from the third rectification column or liquid formed herefrom as an impure oxygen product.
8 more elements
An air separation plant comprising:
- a first rectification column and a second rectification column wherein the first rectification column is configured to operate at a pressure level of 9 to 13.5 bar and the second rectification column is configured to operate at a pressure level of 5.5 to 8.5 bar,
- a first line to supply the first rectification column with cooled compressed air and a second line to supply the second rectification column with liquid from the first rectification column or liquid formed herefrom,
- a first condenser-evaporator for condensing a first portion of head gas from the first rectification column and for evaporating liquid from the second rectification column or liquid formed herefrom, wherein the first condenser-evaporator produces a first evaporation product,
- a second condenser-evaporator for condensing head gas from the second rectification column and for evaporating further liquid from the second rectification column or liquid formed herefrom, wherein the second condenser-evaporator produces a second evaporation product,
- an expansion turbine for decompressing a first portion of the second evaporation product, means for heating the first portion of the second evaporation product, and means for removing from the process the first portion of the second evaporation product, and
- means for removing a second portion of the head gas of the first rectification column from the process as a pure nitrogen product,
- a third rectification column which is configured to operate at a pressure level of 1.1 to 2.5 bar,
- a third condenser-evaporator for condensing a second portion of the second evaporation product and for evaporating liquid from the third rectification column or liquid formed herefrom, wherein the second condenser-evaporator produces a third evaporation product,
- means to supply at least some of the second portion of the second evaporation product condensed in the third condenser-evaporator to the third rectification column,
- means to supply the third rectification column with non-evaporated further liquid from the second rectification column or liquid formed herefrom, and
- means to internally compress sump liquid of the third rectification column or liquid formed herefrom and means to remove the internally compressed sump liquid of the third rectification column or liquid formed herefrom from the process as an impure oxygen product.
8 more elements
Dependencies are inferred from the claim text.