Utilization of nitrogen-enriched streams produced in air separation units comprising split-core main heat exchangers
US11635254B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 28, 2017 |
| Grant date | Apr 25, 2023 |
| Priority date | — |
| Expiry date | Jun 12, 2038 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF25J2245/42
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An air separation apparatus and process, which produces gaseous oxygen and/or nitrogen products at an elevated pressure through internal compression of respective liquid products, are disclosed. Split-core main heat exchangers are employed to warm up product streams generated in an air rectification unit against 1) a main feed air stream in the low-pressure heat exchanger and 2) at least one boosted pressure air stream in the high-pressure exchanger. Because the boosted pressure air stream is at a higher pressure and temperature than the main feed air stream, after separate heat exchange in the split main heat exchangers, the subsidiary waste nitrogen stream exiting the high-pressure heat exchanger is also warmer than the subsidiary waste nitrogen stream exiting the low-pressure heat exchanger. The warmer waste nitrogen stream is fed into the air purification unit for regeneration purposes and the cooler waste nitrogen stream is introduced into the nitrogen water tower to perform cooling duty. The two subsidiary waste nitrogen streams are also connected on the warm side of the main heat exchangers to allow flexible distribution of the flow.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.