Abstract: The method and device serve for generating an oxygen product by low-temperature separation of air having a distillation column system for nitrogen-oxygen separation that comprises a high-pressure column (6) and a low-pressure column (7) which contain mass-transfer sections. Liquid that drains off from the lowest mass-transfer section (32) of the low-pressure column (7) is introduced into a main condenser (8) constructed as a bath evaporator and condenser-evaporator. Between the bottom end of the lowest mass-transfer section (32) of the low-pressure column (7) and the main condenser (8) there is arranged a liquid buffer (33). In the event of a reduction in load, liquid is introduced into the liquid buffer (33) and is stored there. In the event of an increase in load, liquid stored in the liquid buffer (33) is introduced (34) into the main condenser (8).

Abstract: The process serves for generating a pressurized product by low-temperature air fractionation. Feed air (1) is compressed (2), purified (4), cooled (9) and fed to a distillation column system (12) for nitrogen-oxygen separation (11, 23). A liquid product stream (13) is taken off from the distillation column system (12) for nitrogen-oxygen separation, brought (14) in the liquid state to an elevated pressure (PIV) and at this elevated pressure (PIV) vaporized or pseudovaporized (9). The (pseudo)vaporized product stream (16) is fed (17) as pressurized product to a gas pressure reservoir (19) which has a variable pressure (PA). The elevated pressure (PIV) is varied. The elevated pressure (PIV) is varied as a function of the pressure (PA) of the gas pressure reservoir (19).

Abstract: A process and system are used for obtaining a gaseous pressure product by cryogenic separation of air. In the normal operation, charge air is condensed, cooled and fed to a distillation column system; a product fraction is withdrawn-in a liquid condition from the distillation column system, and is introduced into a liquid tank; product liquid is removed from the liquid tank, is pressurized in a pump set in the liquid condition to an increased pressure, is evaporated in an indirect heat exchange with a first heat transfer medium flow, and is withdrawn as a gaseous pressure product. In an emergency operation, product liquid is removed from the liquid tank, is brought in the liquid condition to an increased pressure, is evaporated in an indirect heat exchange with a second heat transfer medium flow, and is withdrawn as a gaseous pressure product.

Abstract: A method to obtain a gaseous product by the low temperature fractionation of air includes supplying a first, purified and cooled stream of air to a high-pressure column. At least one liquid stream from the high-pressure column is passed into a low-pressure column. A product stream in the liquid state is drawn off from the low-pressure column and is brought to an elevated pressure. The product stream is then evaporated in an indirect heat exchange with a second purified stream of air. The second stream of air, which is condensed at least partly during the indirect heat exchange, is expanded at least partly in a work-producing manner. The second stream of air subsequently is passed into the low-pressure column. The pressure of the second stream of air at the outlet of the work-expansion is lower than the operating pressure in the sump of the high-pressure column. The work-expansion of the second stream of air is carried out in a single step.

Abstract: The process and the apparatus are used to obtain argon using a three-column system for the fractionation of air, which has a high-pressure column (11), a low-pressure column (13) and a medium-pressure column (12). A first charge air stream (10, 64) is introduced into the high-pressure column (11), where it is separated into a first oxygen-enriched liquid and a first nitrogen top gas. A first oxygen-enriched fraction (23, 24, 26) from the high-pressure column (11) is introduced into the medium-pressure column (12), where it is separated into a second oxygen-enriched liquid and a second nitrogen top gas. A second oxygen-enriched fraction (33, 35), from the high-pressure column and/or from the medium-pressure column (12), is introduced into the low-pressure column (13), where it is separated into a third oxygen-enriched liquid and a third nitrogen top gas.

Abstract: The process and the apparatus are used to obtain argon using a three-column system for the fractionation of air, which has a high-pressure column (11), a low-pressure column (13) and a medium-pressure column (12). A first charge air stream (10, 64) is introduced into the high-pressure column (11), where it is separated into a first oxygen-enriched liquid and a first nitrogen top gas. A first oxygen-enriched fraction (23, 24, 26) from the high-pressure column (11) is introduced into the medium-pressure column (12), where it is separated into a second oxygen-enriched liquid and a second nitrogen top gas. A second oxygen-enriched fraction (33, 35), from the high-pressure column and/or from the medium-pressure column (12) is introduced into the low-pressure column (13), where it is separated into a third oxygen-enriched liquid and a third nitrogen top gas.

Abstract: The process and the apparatus are used to obtain argon using a three-column system for the fractionation of air, which has a high-pressure column (11), a low-pressure column (13) and a medium-pressure column (12). A first charge air stream (10, 64) is introduced into the high-pressure column (11), where it is separated into a first oxygen-enriched liquid and a first nitrogen top gas. A first oxygen-enriched fraction (23, 24, 26) from the high-pressure column (11) is introduced into the medium-pressure column (12), where it is separated into a second oxygen-enriched liquid and a second nitrogen top gas. A second oxygen-enriched fraction (33, 35), from the high-pressure column and/or from the medium-pressure column (12), is introduced into the low-pressure column (13), where it is separated into a third oxygen-enriched liquid and a third nitrogen top gas.

Abstract: The process and the apparatus are used to obtain argon using a three-column system for the fractionation of air, which has a high-pressure column (11), a low-pressure column (13) and a medium-pressure column (12). A first charge air stream (10, 64) is introduced into the high-pressure column (11), where it is separated into a first oxygen-enriched liquid and a first nitrogen top gas. A first oxygen-enriched fraction (23, 24, 26) from the high-pressure column (11) is introduced into the medium-pressure column (12), where it is separated into a second oxygen-enriched liquid and a second nitrogen top gas. A second oxygen-enriched fraction (33, 35), from the high-pressure column and/or from the medium-pressure column (12) is introduced into the low-pressure column (13), where it is separated into a third oxygen-enriched liquid and a third nitrogen top gas.

Abstract: The process and the apparatus are used for the low-temperature fractionation of air. Charge air (1) which has been compressed and has undergone prior purification is introduced into a rectifier system for nitrogen/oxygen separation. This system comprises a pressure column (2), a low-pressure column (3) and a condenser/evaporator system (101, 102, 103) for heating the low-pressure column (3). The condenser/evaporator system has a first section (101) which is designed as a falling-film evaporator. A first oxygen-rich liquid (6) from the low-pressure column (3) is introduced into the evaporation passages of the falling-film evaporator (101), where it is partially evaporated. In the process, an oxygen-rich vapor (11) and a second oxygen-rich liquid (12) are formed. At least part of the oxygen-rich vapor (11) is returned to the low-pressure column (3). The condenser/evaporator system additionally has a second section (102, 103), which is designed at least in part as a forced circulation evaporator (103).

Abstract: The process and the apparatus serve for the low-temperature fractionation of air. Compressed and prepurified feed air (3, 5) is introduced into a rectification system for nitrogen-oxygen separation which has a pressure column (6). At least a part of the compressed and prepurified feed air is fed (5) to the pressure column (6). An oxygen-enriched fraction (13) is taken off from the pressure column (6) and passed (14) to a further working step (7) within the rectification system. The oxygen-enriched fraction (13) is taken off at least one theoretical or actual plate (15) above the point at which the compressed and prepurified feed air (5) is fed to the pressure column. From the bottom of the pressure column (6) a purge fraction (16) is removed in the. liquid state, fed in the liquid state to a purification stage (17), in which N2O is removed, and is taken off from the purification stage (17) as purified purge fraction (18).

Abstract: A method to obtain a gaseous product by the low temperature fractionation of air includes supplying a first, purified and cooled stream of air to a high-pressure column. At least one liquid stream from the high-pressure column is passed into a low-pressure column. A product stream in the liquid state is drawn off from the low-pressure column and is brought to an elevated pressure. The product stream is then evaporated in an indirect heat exchange with a second purified stream of air. The second stream of air, which is condensed at least partly during the indirect heat exchange, is expanded at least partly in a work-producing manner. The second stream of air subsequently is passed into the low-pressure column. The pressure of the second stream of air at the outlet of the work-expansion is lower than the operating pressure in the sump of the high-pressure column. The work-expansion of the second stream of air is carried out in a single step.

Abstract: The process and the apparatus serve for evaporating liquid oxygen. In the normal operation liquid oxygen is introduced into a main evaporator (3) and there partially evaporated, a first flushing stream (5) is removed in the liquid state from the main evaporator (3), the first flushing stream (5) is partially evaporated in an auxiliary evaporator (6) and a second flushing stream (7) is taken off in the liquid state from the auxiliary evaporator (6). The normal operation is interrupted by a heating operation in which no liquid (5) is passed from the main evaporator (3) into the auxiliary evaporator (6) and the auxiliary evaporator (6) is brought to a temperature which is markedly higher than its temperature in the normal operation.

Abstract: The process and the device are used for low-temperature separation of air. A first split stream of compressed and purified air is cooled, fed to a main rectifying system and separated there into liquid oxygen and gaseous nitrogen. A liquid product fraction (for example, oxygen and/or nitrogen) is vaporized in indirect heat exchange with a second split stream of compressed and purified air. The second split stream condenses during indirect heat exchange at least partially. At least a portion of the second split stream, downstream from indirect heat exchange with the liquid product fraction, is used as cooling medium for top cooling of a crude argon column downstream from the main rectifying system. The second split stream makes available all or essentially all the cold needed for liquefaction of crude argon.