| 摘要 |
The process and the apparatus are used for low-temperature air fractionation. Input air (8) is cooled in a main heat exchanger (9) and introduced into a single column (12) for obtaining nitrogen (11, 43). A nitrogen product stream (15, 16, 17) is removed from the upper region of the single column (12). A first residual fraction (18, 29) is removed from the lower or central region of the single column (12), re-compressed (30) and then fed to the single column (12) again (32). An oxygen-containing stream (36) is removed from the single column (12) at an intermediate point and fed to a pure oxygen column (38) (39). A pure oxygen product stream (41) in the liquid state is removed from the lower region of the pure oxygen column (38). The pure oxygen product stream (41, 56) is evaporated and warmed with respect to input air (8) in the main heat exchanger (9) and finally obtained as a gaseous product (57).
|
