An annular divided wall column for the cryogenic rectification of air or constituents of air is provided. The annular divided wall column includes a first annular column wall and a second annular column wall disposed within the first annular column wall and radially spaced therefrom to define an annulus column region as the space between the first annular column wall and the second annular column wall. An interior core column region is also defined by the interior space of the second annular column wall. The present annular divided wall column further includes a plurality of packing elements, plurality of trays or a heat exchange device disposed within the interior core column region; and a plurality of packing elements disposed within the annulus column region.

An annular divided wall column for the cryogenic rectification of air or constituents of air is provided. The annular divided wall column includes a first annular column wall and a second annular column wall disposed within the first annular column wall and radially spaced therefrom to define an annulus column region as the space between the first annular column wall and the second annular column wall. An interior core column region is also defined by the interior space of the second annular column wall. The present annular divided wall column further includes a plurality of packing elements, plurality of trays or a heat exchange device disposed within the interior core column region; and a plurality of packing elements disposed within the annulus column region.

An apparatus for separation of air by cryogenic distillation comprising: a system of columns; a first turbine; a warm compressor coupled to the first turbine; a second turbine; a cold compressor coupled to the second turbine; a heat exchanger; means for sending air cooled in the heat exchanger at an intermediate temperature of the heat exchanger to the cold compressor; means for sending expanded air from the second turbine to the system of columns; means for sending air compressed in the cold compressor to an intermediate point of the heat exchanger and then at least in part to the system of columns via a first valve; means for sending air compressed in the cold compressor to the inlet of the first turbine via a second valve without passing through the heat exchanger, wherein the means for sending air compressed in the cold compressor to the inlet of the first turbine via the second valve without passing through the heat exchanger is also connected to the inlet of the first turbine; means for sending a fraction of air cooled in the heat exchanger to an intermediate temperature of the latter to the first turbine; means for sending expanded air from the first turbine to the system of columns; and a bypass line provided with an expansion valve configured to send air from the cold compressor to the system of columns without passing through the heat exchanger.

Method for separating air by cryogenic distillation in an air separation device comprising a system of columns, a first turbine and a second turbine, wherein, in de-icing operation, a common duct bringing air from the two turbines to a column is closed by means of an isolation valve, a purge gas is sent to the turbines at a temperature above 0 C. in order to de-ice them, but purge gas is not sent to the system of columns.

Method for separating air by cryogenic distillation, wherein at least part of the air to be distilled is boosted in an air booster, compressed air is allowed to expand in at least one expansion turbine and, if the pressure drop between two points of the booster passes under a threshold and/or a flow of the booster passes under a minimum flow of the booster, part of the air boosted in the booster is allowed to expand without having been cooled between the booster and the expansion turbine and the boosted expanded air is sent upstream or downstream of the at least one turbine, without having been cooled in the heat exchanger, after having been boosted.

Method for separating air by cryogenic distillation, wherein air is compressed in a compressor and is subsequently sent to a heat exchanger, with the air cooled in the exchanger being sent to a check valve downstream of the heat exchanger and subsequently to a turbine, the valve being positioned so that air from a short-circuiting duct cannot return to the exchanger from the compressor.

An apparatus for distillation at cryogenic temperatures can include a cold box module comprising framing and having an upper module section and a lower module section, wherein the upper module comprises a roof; an upper column section disposed within the upper module section; a lower column section disposed within the lower module section; a plurality of support saddles attached to the upper and lower module sections that are configured to provide structural support for the upper and lower column sections when the upper and lower column sections are in a horizontal position during transportation; and means for limiting longitudinal movement of the lower column section when the lower module section is in a horizontal position during transport, wherein the means for limiting longitudinal movement are connected to the lower column section and the lower module section.

A method for constructing a cold box module and resulting apparatus is provided. The method can include providing a cold box module having framing and an upper and lower module sections, introducing an upper column section longitudinally into the upper module section while the upper module section is substantially horizontal; introducing a lower column section longitudinally into the lower module section while the lower module section is substantially horizontal; releasably attaching the lower column section to the lower module section using shipping saddle spacers and support saddles; and attaching a skirt attachment to the lower column section and the lower module section, wherein the skirt attachment is configured to limit longitudinal movement of the lower column section when the lower module section is in a horizontal position during transport. After erecting the cold box module at the installation site, the shipping saddle spacers can be removed and the upper column section is lowered using a jacking system located on the roof of the cold box module.

A method for installation of a cryogenic distillation apparatus is provided. The method can include the steps of: providing an upper module section having an upper column section disposed within and secured to the upper module section, wherein the upper module comprises a roof; providing a lower module section having a lower column section disposed within and secured to the lower module section; erecting the lower module section from a horizontal position to a vertical position at an installation site; lifting the upper module section from a horizontal position and attaching the upper module section, while in a vertical position, to a top portion of the lower module section; lowering the upper column section, independent of the upper module section, toward the lower column section; and welding the upper column section and the lower column section together.

The jacking system and method for using it to lower an upper column section without the use of a crane is provided. The jacking system is configured to be disposed on a roof of a cold box module and may include: a structural assembly; and a plurality of suspension rods supported at an upper end by the structural assembly, wherein the plurality of suspension rods is configured to provide support to the upper column section