A moderate pressure air separation unit and air separation cycle is disclosed that provides for up to about 96% recovery of argon, an overall nitrogen recovery of 98% or greater and limited gaseous oxygen production. The air separation is configured to produce a first high purity oxygen enriched stream and a second lower purity oxygen enriched stream from the lower pressure column, one of which is used as the refrigerant to condense the argon in the argon condenser, with the resulting vaporized oxygen stream used to regenerate the temperature swing adsorption pre-purifier unit. All or a portion of the first high purity oxygen enriched stream is vaporized in the main heat exchanger to produce the gaseous oxygen products.

A heat exchanger 1 comprises a shell 2 which has in an interior thereof a heat exchange chamber 20 in which a gas to be cooled or an intermediate medium is filled, and performs heat exchange directly or indirectly between liquid hydrogen and the gas to be cooled, in the interior of the heat exchange chamber 20; a tray 23 which is provided in the interior of the heat exchange chamber 20 and receives a liquefied gas and a deposited substance F which are generated by the heat exchange in the interior of the heat exchange chamber 20; and a liquid discharge mechanism (flashboard 22, drain port 25, and drain pipe 26) which discharges the liquefied gas from the tray 23 in a state in which the deposited substance F is left in the tray 23.

A nitrogen production system that can produce high purity nitrogen containing a desired concentration of oxygen and ultrahigh purity nitrogen containing a desired concentration of argon in a single rectifying column while restraining increase in electric power consumption, and a production process thereof are provided. The nitrogen production system includes a heat exchanger that cools material air, a nitrogen rectifying column including a rectifying unit into which the material air cooled by the heat exchanger is introduced and a condenser that is located in a column top, a first introduction pipe that introduces the material air from the heat exchanger into a buffer unit located at a lower part from a position of the rectifying unit, a second introduction pipe for introducing an oxygen-enriched liquefied gas into the condenser from the buffer unit of the nitrogen rectifying column, a first derivation pipe for deriving ultrahigh purity nitrogen from the rectifying unit and recovering the ultrahigh purity nitrogen, and a second derivation pipe for deriving high purity nitrogen from an intermediate plate of the rectifying unit and recovering the high purity nitrogen.

This invention is about an air separation apparatus to produce oxygen and nitrogen through isobaric separation, which is based on the Rankine cycle system of similar thermal energy power circulation apparatus at cryogenic side, a liquid pump is used to input work and the cold is made up to the air separation apparatus with refrigerating media, so as to realize the isobaric separation of air to produce nitrogen and oxygen. The air separation apparatus of this invention can save energy by over 30% as compared with the traditional advanced apparatus with the identical refrigerating capacity, and it can also realize centralize gas supply via the air separation apparatus, therefore it constitutes a breakthrough to the traditional air separation technology and refrigeration theory, with substantial economic, social and environmental protection benefits.

An ultra-high-purity oxygen production method and apparatus are provide, in which the method can include a step in which feed oxygen comprising low-boiling-point components as impurities is introduced from a warm end of a main heat exchanger and cooled, then introduced into an oxygen rectification column, and product ultra-high-purity oxygen from which the low-boiling-point components have been removed is drawn as a gas or a liquid from a lower portion of the oxygen rectification column.

One object of the present invention is to provide a compact multistage liquid storage-type condenser-evaporator capable of producing two kinds of gases having different compositions without increasing power, and a nitrogen production device using the multistage liquid storage-type condenser-evaporator without increasing the power for producing nitrogen, and the present invention provides a multistage liquid storage-type condenser-evaporator including a bottom liquid storage section which is configured to store the liquid supplied into the bottom evaporation passage without circulating, and a fluid collection section which is configured to collect the fluid which flows out from the bottom evaporation passage and discharge to the outside without returning into the bottom liquid storage section.

A method for the production of liquefied natural gas (LNG) using a cold fluid provided from a cryogenic unit, such as an air separation unit or nitrogen liquefier, is provided. The method may include the steps of: withdrawing a nitrogen stream from a cryogenic unit, wherein the nitrogen stream is at a temperature between about 155 C. to about 193 C.; and liquefying a natural gas stream in a natural gas liquefaction unit using the nitrogen stream from the cryogenic unit.

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 method for providing a nitrogen product, an oxygen product and a hydrogen product, wherein an air separation installation is used which is designed for the low-temperature separation of feed air and which has a rectification column system, the rectification column system comprising an air-fed rectification column and a main heat exchanger. The provision of the nitrogen product comprises, in particular, subjecting feed air to low-temperature rectification using the air-fed rectification column such that a tops gas is obtained, and using part of the tops gas as the nitrogen product. The provision of the oxygen product and the hydrogen product comprises subjecting water to water electrolysis in an electrolyzer, such that a water-containing oxygen stream and a hydrogen stream are obtained, the water-containing oxygen stream or part thereof being subjected, at least in one operating phase, to drying and, in an unmixed state, to liquefaction in the air separation installation.

A system for generating an inert fluid, the system being carried on board an aircraft, the generation system including a plurality of devices configured each, in succession, to execute a separation of components of a primary fluid initially collected in the form of compressed hot air, the system including at least one heat exchanger configured to execute a separation of components, by change of phase of a component of the primary fluid, executing a cooling of the primary fluid using liquid hydrogen, supplied with liquid hydrogen collected from a tank of the aircraft. It is thus possible to generate an inert gas without requiring membrane separation of the nitrogen and the oxygen, and while at the same time making it easier to warm the liquid hydrogen stored and used in the aircraft as a source of energy.