Abstract: A cryogenic air separation process having improved flexibility and operating efficiency for producing elevated pressure gaseous oxygen by vaporizing pressurized liquid oxygen wherein refrigeration generation for the process is decoupled from the flow of process streams and is produced by one or more multicomponent refrigerant fluid circuits.

Abstract: A system for generating refrigeration and providing the refrigeration into a cryogenic rectification plant wherein, in addition to refrigeration generated by turboexpansion, further refrigeration for the plant is generated by a recirculating multicomponent refrigerant in a refrigeration circuit.

Abstract: A method for low temperature separation of fluids wherein the separation process is sustained by refrigeration generated by a recirculating multicomponent refrigerant fluid.

Abstract: A dual feed pressure cryogenic air separation system wherein all the feed air is pressurized to an intermediate pressure and cleaned of high boiling impurities at that intermediate pressure, and a portion further compressed to the high pressure and then cooled against another portion so as to prepare that other portion for the turboexpansion to the low pressure, preferably with the turboexpansion driving the further compression.

Abstract: A process and a plant in which gaseous oxygen is produced directly at the desired high pressure by pumping liquid oxygen drawn off in the vessel of the low-pressure column (11). The air to be distilled is split into three flows: a flow at the medium pressure of the double distillation column (1), a flow at a high pressure, higher than approximately 60 bars, and a flow at an intermediate pressure which, after partial cooling, is expanded to the medium pressure in a turbine (8). The intermediate pressure is chosen so that the air treated in the turbine is near its dew point at the entry of the turbine wheel. Liquid product is simultaneously drawn off (at 24) from the plant.

Abstract: In a process for the production of gas under pressure by cryogenic distillation, the gas is produced by vaporizing (or pseudo-vaporizing) a liquid drawn off from a distillation column. In order to supply additional gas under pressure, a flow of a gas coming from an external source is at least partially liquefied, and the liquid thus formed is added to the liquid drawn off from the column before or after an optional pressurization step.

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: An air separation plant and process in which a first stream of compressed feed air is introduced in vapour state into a higher pressure rectification column and separated therein into nitrogen vapour and oxygen-enriched liquid air and a flow of the nitrogen vapour is condensed in condenser-reboiler. A flow of the oxygen-enriched liquid air is separated in a reboiled lower pressure rectification column into nitrogen-rich and oxygen-rich fractions. A first flow of the condensed nitrogen is employed as reflux in the higher pressure rectification column and a second flow of the condensed nitrogen is employed as reflux in the lower pressure rectification column. A flow of compressed feed air is expanded in expansion turbine with the performance of external work so as to create refrigeration for the process. Products of the separation include one or both of a gaseous nitrogen product taken from the higher pressure rectification column and a liquid nitrogen product.