A cryogenic air separation apparatus comprises: a heat exchanger, a first rectification column, a first condenser, a second rectification column, a third rectification column, a second condenser, a high-purity oxygen rectification column, a third condenser, a nitrogen compressor, and a compressed recycled gas line L52 for introducing product nitrogen gas compressed by the first nitrogen compressor into a warm end (heat source) of an ultra-high-purity oxygen vaporizer as a compressed recycled gas.

System for purifying argon by cryogenic distillation, comprising a single column surmounted by a top-end condenser, a fluid inlet in the lower part of the column, a fluid outlet in the upper part of the column, and N distillation sections where N≥4, of which at least the two uppermost sections of the column are equipped respectively with a first liquid distributor and with a second liquid distributor, the second distributor being capable of performing a function of mixing together liquids that fall onto the distributor, each of the first and second distributors being positioned above the respective section and of which the two lowermost sections of the column are respectively equipped with a (N−1)th and an Nth liquid distributor capable of performing a function of mixing together liquids that fall onto the distributor, and which is arranged above the respective section, the first, second, (N−1)th and Nth distributors each being dimensioned to contain a maximum height of liquid head, that (those) of the first and second distributors being greater than that (those) of the (N−1)th and Nth distributors.

A nitrogen liquefier configured to be integrated with an argon and nitrogen producing cryogenic air separation unit and method of nitrogen liquefaction are provided. The integrated nitrogen liquefier and associated methods may be operated in at least three distinct modes including: (i) a nil liquid nitrogen mode; (ii) a low liquid nitrogen mode; and (iii) a high liquid nitrogen mode. The present systems and methods are further characterized in an oxygen enriched stream from the lower pressure column of the air separation unit is an oxygen enriched condensing medium used in the argon condenser.

A nitrogen producing cryogenic air separation unit with an excess air circuit is provided. The nitrogen producing cryogenic air separation unit is capable of producing high pressure gaseous nitrogen without the use of a nitrogen product compressors and is also capable of producing high rates of liquid nitrogen without adding additional compression stages in the main air compressor and/or without a nitrogen recycle compressor.

An apparatus for analyzing the content of at least one contaminant in a liquid cryogen comprising a cylindrical enclosure, an annular enclosure arranged around the cylindrical enclosure, means for dividing a flow of liquid cryogen in two, means for delivering a first part of the liquid cryogen to the cylindrical enclosure, means for delivering a second part of the liquid cryogen to the annular enclosure, a pipe connected to the cylindrical enclosure to allow vaporized liquid to pass through, a pipe connected to the annular enclosure to allow vaporized liquid to pass through, a heater for heating the cylindrical enclosure vessel and means for stopping the delivery of liquid cryogen to the cylindrical enclosure.

The present disclosure provides a method for cryogenic air separation. In the method, part (b2) of the air (b) is compressed in warm booster (7), cooled in heat exchanger (2) and then divided in two, one part (c1) being compressed in a cold booster(9) driven by one turboexpander (11) in which the other part (c2) of air (c) is expanded, and another part of the feed air is not boosted but is expanded in another turboexpander (6) which drives the warm booster (7). The present disclosure also provides an apparatus for cryogenic air separation.

A method and apparatus for purifying air via a pre-purification unit (PPU) of an air separation unit (ASU) system can include passing air through a first adsorber of the PPU to purify the air for operation of the ASU system while it is at or below a first pre-selected operational capacity. In response to the operational capacity of the ASU system needing to be increased to a level above the first pre-selected operational capacity threshold, a second adsorber can be brought on-line in parallel with the first adsorber or in series with the first adsorber to provide improved purification capacity to account for the increased demand for purification capacity resulting from the increased operational capacity of the ASU system. This second adsorber can be different from the first adsorber (e.g. different in size, adsorption capacity for impurities within air, and/or configuration, etc.).

One object of the present invention is to provide a multistage bath condenser-reboiler capable of suppressing a decrease in condensation efficiency and making it compact. The present invention provides a multistage bath condenser-reboiler, including: a heat exchange core including a heat exchange section formed by adjacently stacking an evaporation passage through which liquid to be evaporated flows, and which is partitioned into a plurality of stages, and a condensation passage through which gas is condensed by heat exchange with the liquid; a liquid reservoir which is configured to store liquid which is supplied into the evaporation passage or flowed out from the evaporation passage; and a liquid communication passage which is configured to flow the liquid in the liquid reservoir from an upper liquid reservoir into a lower liquid reservoir; and the liquid reservoir is provided for each evaporation passage partitioned into the plurality of stages on at least one side surface in a width direction of the heat exchanger core, which is orthogonal to a stacking direction of the condensation passage and the evaporation passage, wherein the condensation passage is divided at least two stages, and wherein the multistage bath condenser-reboiler further comprises: a gas header which is provided at the top of each stage of the condensation passage to supply the gas into the condensation passage of each stage; condensation inlet flow channels which introduce the gas supplied in the gas header into the condensation passage; a liquid header which is provided at the bottom of each stage of the condensation passage, and collects liquid generated by condensation of the gas in the condensation passage, and condensation outlet flow channels which flow out the liquid generated by condensation into the liquid header.

A process for producing liquid oxygen, including, a first operating mode, and a second operating mode. During the first operating mode, the distillation column produces a first flowrate of product liquid oxygen, and a first flow rate of liquid nitrogen product. During the second operating mode, the distillation column produces a second flowrate of product liquid oxygen, and a second flow rate of liquid nitrogen product. Wherein, the second flowrate of product liquid oxygen is greater than the first flowrate of product liquid oxygen.

A method for cryogenic separation of air uses an air separation plant, wherein, in a mass transfer column, a liquid first fluid and a gaseous second fluid are subjected to mass transfer with one another. A gaseous third fluid is removed from the column and is at least partly discharged from the air separation plant. A liquid fourth fluid is removed from the column and is at least partly fed into a low-pressure column. The first fluid is formed using at least a part of an oxygen-rich liquid removed from the low-pressure column. The second fluid is formed using an oxygen-enriched liquid removed from a high-pressure column. The oxygen-enriched liquid removed from the high-pressure column and bottom liquid of the mass transfer column are mixed and partly evaporated in a condenser-evaporator. A liquid fifth fluid is removed from the mass transfer column between a feed point for the first fluid and a feed point for the oxygen-enriched liquid, and is at least partly fed into the low-pressure column. The fifth fluid or a fraction thereof is fed into the low-pressure column below the fourth fluid or a fraction thereof.