In a process for the separation of a mixture containing hydrogen and carbon monoxide to produce gaseous hydrogen, the mixture is cooled down to a temperature below −180° C. and then separated at a temperature below −100° C. to produce a gas enriched in hydrogen and a fluid enriched in carbon monoxide, at least a part of the gas enriched in hydrogen is sent to a pressure swing adsorption separation apparatus operating at a temperature above 0° C. to produce a gas rich in hydrogen at a pressure of at least 20 bars, and at least a part of the gas rich in hydrogen is cooled in the heat exchanger down to a temperature below −100° C., reduced in pressure in a turbine down to a pressure of at least 8 bars and reheated in the heat exchanger to constitute a product rich in hydrogen at a pressure of at least 8 bars.

A method for an improved integration of refrigeration into conventional natural gas processing plants which use propane or similar hydrocarbon refrigerants either to supplement cooling by turbo-expanders or as the sole source of refrigeration.

A method and system for controlling the nitrogen concentration in an LNG product and fuel from flash gas within preferred ranges. A cooled LNG stream is separated into a nitrogen-enriched vapor stream, a fuel stream, and an LNG product stream using a plurality of phase separating devices, such as flash drum or rectifying column. A portion of the vapor stream is recycled to the rectifying column as reflux. A portion of a stream having a higher concentration of nitrogen is combined with the fuel stream to maintain the fuel stream within a desired nitrogen concentration range.

A system includes a heat exchanger including a first inlet for receiving a first pressurized gas stream and a first outlet for outputting a chilled gas stream produced by the heat exchanger cooling the first pressurized gas stream. The system also includes a turbo expander connected to the first outlet of the heat exchanger for receiving the chilled gas stream from the heat exchanger and producing a partially liquified gas stream, the partially liquified gas stream comprising vapors and LNG. The system further includes at least one separator connected to the turbo expander, wherein the partially liquified gas stream is fed into the at least one separator, and the at least one separator separates the vapors from the LNG.

A design is provided to convert a gas subcooled process plant to a recycle split vapor process for recovering ethane and propane from natural gas. When in operation, the recovery of ethane and propane can exceed 97 to 99 wt. % of the stream being processed. A second smaller demethanizer column is added to the gas subcooled process plant as well as the addition of several cryogenic pumps.

This method comprises passing a residual stream into a flash drum to form a gaseous overhead flow and liquid bottom flow, and feeding the bottom flow into a distillation column, It comprises cooling the overhead flow in a heat exchanger to form a cooled overhead flow. It comprises the extraction of a gaseous overhead stream at the head of the distillation column, and the formation of at least one effluent stream from the overhead stream and/or from the top stream. The separation of the cooled overhead flow comprises passing the cooled overhead flow into an absorber, and injecting a methane-rich stream into the absorber to place the cooled overhead flow in contact with the methane-rich stream.

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.

A pressurized CO.sub.2 rich gas is cooled down to condense at least part of the stream in a heat exchanger. A bulk of the CO.sub.2 is separated by partial condensation and distillation in order to obtain at least one non-condensable gas from a separation vessel. The non-condensable gas is optionally heated up to a temperature lower than −20° C. (membranes performances is greatly enhanced by low temperature operation). The non-condensable gas is introduced into a membrane permeation unit, producing a residue stream and a permeate stream (the permeate stream is enriched in CO.sub.2). The permeate stream is recycled to the process, optionally after compression. The method is auto-refrigerated, i. e. no external refrigerant is used to provide cooling below 0° C.

One or more specific embodiments disclosed herein includes a method for separating hydrogen from an olefin hydrocarbon rich compressed effluent vapor stream, employing a integrated heat exchanger, multiple gas-liquid separators, external refrigeration systems, and a rectifier attached to a liquid product drum.

Implementations described and claimed herein provide systems and methods for processing liquefied natural gas (LNG). In one implementation, a dry feed gas is received. The dry feed gas is chilled with clean vapor from a heavies removal column to form a chilled feed gas. The chilled feed gas is partially condensed into a vapor phase and a liquid phase. The liquid phase retains freezing components. The freezing components are extracted using a reflux stream in the heavies removal column. The freezing components are removed as a condensate. The vapor phase is compressed into a clean feed gas. The clean feed gas is free of the freezing components for downstream liquefaction.