A method and device for purifying a process gas mixture, such as a cryogen gas, in which impurity components of the mixture are removed by de-sublimation via cryo-condensation. The gas mixture is cooled to a temperature well below the condensation temperature of the impurities, by direct exchange of the gas mixture with a cooling source disposed in a first region of the device. The de-sublimated or frozen impurities collect about the cooling region surfaces, and ultimately transferred to a portion of the device defining an impurities storage region. The output-purified gas is transferred from the impurities storage region, is optionally passed through a first micrometer sized filter, through a counter-flow heat exchanger, and ultimately up to an output port at room temperature. A method of purging the collected impurities and regenerating the device is also disclosed.

The invention relates to a method for producing helium from a source gas stream (1) including at least helium, methane, nitrogen and hydrogen, comprising at least the following consecutive steps: step a): injecting said source gas stream (1) into at least one compressor (3); step b): eliminating the hydrogen and the methane by reacting the stream (4) obtained from step a) with oxygen; step c): eliminating at least the impurities from step b) by temperature swing adsorption (TSA); step d): partially condensing the stream (8) obtained from step c) in order to produce a stream (10) of liquid nitrogen and a gas stream (11) comprising mostly helium; step e): purifying the gas stream (11) obtained from step d) in order to increase the helium content by pressure swing adsorption (PSA) by eliminating the nitrogen and the impurities contained in the gas stream (11) obtained from step d).

Systems and methods are provided for recovering helium from a feed comprising helium, carbon dioxide, and at least one of nitrogen and methane. The feed is separated in a first separator to form helium-enriched stream and a CO.sub.2-enriched stream. The helium-enriched stream is separated in a pressure swing adsorption unit to form a helium-rich product stream and a helium-lean stream. At least a portion of the helium-lean stream is recycled to the first separator with the feed. In some embodiments, a membrane separation unit is used to enhance helium recovery.

In a compression process in a dynamic compressor having at least one first and one second compression stages, a first gas having a first molecular weight of less than 10 g/mol is compressed, at least one second fluid having a second molecular weight greater than 50 g/mol is mixed with the first gas to form a third gas to be compressed having a molecular weight greater than 10 g/mol, the third gas is sent to the first compression stage, the third gas is cooled in a first heat exchanger downstream of the first compression stage, where it is partially condensed, the partially condensed third gas is sent to a first phase separator to form a fourth gas having a lower molecular weight than the third gas and a first condensed liquid having a higher molecular weight than the third gas, the fourth gas is sent from the first phase separator to the second compression stage, the fourth gas compressed in the second compression stage is sent to cool in a second heat exchanger where it partially condenses, and the partially condensed fourth gas is sent to a second phase separator to produce a fifth gas having a lower molecular weight than the fourth gas.

The invention relates to a facility for producing liquid helium from a source gas mixture substantially comprising nitrogen and helium. The facility includes a cryogenic purifier including a system for separating the nitrogen from the source gas mixture with a view to producing helium at a temperature lower than the temperature of the source gas. The facility also includes a helium liquefier that subjects the helium to a work cycle including, in series: compressing the helium, cooling and decompressing the compressed helium, and reheating the cooled, decompressed helium. The facility includes a helium transfer pipe connecting an outlet of the purifier to an inlet of the liquefier in order to transfer helium produced by the purifier into the work cycle of the liquefier. The facility is characterized in that the cryogenic purifier includes a decompression system that includes an inlet to be connected to a source of pressurized nitrogen gas. Said system for decompressing the nitrogen gas exchanges heat with the separation system in order to transfer cold from the decompressed nitrogen gas to said separation system.

A low-temperature device for separating and purifying gas based on a small-sized low-temperature refrigerating machine includes a primary, secondary and quaternary heat exchanger, at least one small-sized low-temperature refrigerating machine, and at least one liquid collecting tank. The small-sized low-temperature refrigerating machine includes a first cold head and a second cold head, the secondary heat exchanger is provided on the first cold head to form a primary cold head heat exchanger, the quaternary heat exchanger is provided on the second cold head to form a secondary cold head heat exchanger, a mixed gas outlet is connected to an inlet of the primary cold head heat exchanger. By using primary and secondary cold heads of the small-sized low-temperature refrigerating machine as cold sources, gases having different condensing temperature are liquefied and solidified separately, and two or more gases can be separated and purified at a lower cost.

The present invention relates a process and apparatus that recovers a helium rich stream from a mixed gas having low concentrations of helium therein. More specifically, the invention relates to an integrated process and apparatus for treating a mixed feed gas from an operating process that produces a liquid product from natural gas containing helium, such as processes that produce ammonia, methanol, or liquid hydrocarbons.

Systems and methods are provided for recovering helium from a feed comprising helium, carbon dioxide, and at least one of nitrogen and methane. The feed is separated in a first separator to form helium-enriched stream and a CO.sub.2-enriched stream. The helium-enriched stream is separated in a pressure swing adsorption unit to form a helium-rich product stream and a helium-lean stream. At least a portion of the helium-lean stream is recycled to the first separator with the feed. In some embodiments, a membrane separation unit is used to enhance helium recovery.

Disclosed is a method for purifying a main gas, in particular helium, from a source gas stream comprising the main gas, a main impurity, in particular nitrogen, and optionally another, secondary impurity, in particular oxygen, the method comprising a step of partial condensation of the gas stream in order to extract therefrom impurities in liquid form, in particular the main impurity, and to produce a gas stream enriched with main gas, characterized in that the method comprises, before the partial condensation step, a step of injecting into the gas stream a compound in which the main impurity of the gas to be treated is soluble and having a saturation vapor pressure lower than the saturation vapor pressure of the main impurity.

Disclosed is a gas separation arrangement for separating and containing various types of gas received from a collection chamber. In certain embodiments, the gas separation arrangement is envisioned to assist in mining select gases from the Moon. The arrangement includes plurality of progressively chilled separation tanks that successively separate out different species of gas. The separation tanks are connected to and receive the various gas species from the collection chamber. Each separation tank can have an independent heat exchanger that maintains the respective separation tank at a temperature that selectively liquifies/precipitates out a target species of gas allowing the remaining gas to move to a successive separation tank. Ultimately, He-3 and He-4 are separated from one another to be collected, like the other gas species.