Abstract: Air is distilled in a single column installed on a boat, and from here an oxygen-enriched liquid flow is drawn off. This flow is pressurized by a pump and vaporized by heat exchange with air or nitrogen. The oxygen is used for the partial oxidation of a flow contained hydrocarbons, for example natural gas.

Abstract: Air is separated by rectification. The air is compressed in a main air compressor to a first pressure. Without further compression a first flow of the compressed air is cooled in a main heat exchanger to a temperature suitable for its separation by rectification. The first flow is introduced into the higher pressure column of a double rectification column comprising, in addition to the higher pressure column, a lower pressure column, in which a bottom oxygen fraction containing from about 50 to about 96 mole percent of oxygen is formed. A condenser-reboiler places the higher pressure column in heat exchange relationship with the lower pressure rectification column. A second flow of the compressed air is expanded with the performance of external work in an expansion turbine without further compression of the second flow upstream of the expansion. The expanded second flow is introduced into the lower pressure rectification column. An impure oxygen product is taken from the said bottom fraction.

Abstract: A cryogenic air separation system wherein a portion of the feed air is compressed to a very high pressure, bypasses the primary heat exchanger, and is turboexpanded to a low pressure to supply refrigeration in one step from the warm end temperature to the cryogenic temperature of the cryogenic air separation plant.

Abstract: A cryogenic rectification system wherein feed air is turboexpanded to generate refrigeration through two turboexpanders operating at the same inlet pressure but at different inlet temperatures enabling the turboexpanders to efficiently drive the compressor or compressors which compress the feed air to the single expansion pressure.

Abstract: The process and apparatus are based on a triple-column system, having at least a high-pressure column (7), a medium-pressure column (8) and a low-pressure column (9). Feed air (1) is compressed to a first pressure (2). A first partial stream (101, 103, 104) of the resultant air feed (3) is sent into high-pressure column (7) after it has been compressed to a second pressure (5, 102), which is at least equal to the operating pressure of the high-pressure column (7). A second partial stream (201, 202) of the compressed air feed (3) is fed into the medium-pressure column (8). A third partial stream (301, 303, 304) of the compressed air feed (3) is engine-expanded (305) and then fed (306) into the low-pressure column (9). Fractions (18; 26) from the high-pressure column (7) and the medium-pressure column (8) are introduced at least partially into low-pressure column (19, 20; 28, 29). Nitrogen-enriched top fractions (10; 21) from high-pressure column (7) and medium-pressure column (8) are condensed (11; 22).

Abstract: A process is set forth for the cryogenic distillation of an air feed to produce an oxygen product, particularly an oxygen product at moderate purity (80-99%, preferably 85-95%). The process uses an auxiliary low pressure column in addition to the conventional high pressure column and low pressure column. The auxiliary low pressure column, which is preferably operated at the same pressure as the main low pressure column and which is heat integrated with the top of the high pressure column by means of its bottom reboiler/condenser, pretreats the crude liquid oxygen from the bottom of the high pressure column. The resulting overhead vapor stream and bottom stream are subsequently fed to the main low pressure column. Preferably, the bottom stream is fed to the main low pressure column in a state which is at least partially vapor.

Abstract: A cryogenic method and apparatus using a liquefier and a two stage distillation column capable of operating in two modes, namely a first mode of operation during which only liquid nitrogen is produced and a second mode of operation during which liquid nitrogen and liquid oxygen are produced. By adjusting the time of operation in each mode, any ratio of liquid nitrogen to liquid oxygen greater than the ratio achieved during the second mode of operation can be achieved. In the first mode of operation, a condenser is used to condense the lower pressure stage gaseous nitrogen into lower pressure stage nitrogen condensate. To condense the lower pressure stage gaseous nitrogen, either at least a portion of the crude oxygen liquid from the higher pressure stage, at least a portion of the oxygen-enriched liquid from the lower pressure stage, at least a portion of the liquefied air, or mixtures thereof, are introduced to the condenser.

Abstract: A cryogenic rectification system for producing elevated pressure gaseous oxygen wherein pressurized liquid oxygen is vaporized against pressurized working fluid which is then turboexpanded to form a dual phase stream having both vapor and liquid fractions.