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.

A system and method for removing nitrogen from natural gas using two fractionating columns, that may be stacked, and a plurality of separators and heat exchangers, with horsepower requirements that are 50-80% of requirements for prior art systems. The fractionating columns operate at different pressures. A feed stream is separated with a vapor portion feeding the first column to produce a first column bottoms stream that is split into multiple portions at different pressures and first column overhead stream that is split or separated into two portions at least one of which is subcooled prior to feeding the top of the second column. Optional heat exchange between first column and second column streams provides first column reflux and reboil heat for a second column ascending vapor stream. Three sales gas streams are produced, each at a different pressure.

A system and method for co-producing ultra-high purity oxygen and ultra-high purity hydrogen from a water electrolysis unit is provided. The presently disclosed system and method includes upgrading the crude oxygen stream coming from the water electrolysis unit by means of a small, stand-alone cryogenic distillation system wherein the refrigeration for such cryogenic distillation system is supplied by a nitrogen recycle refrigeration loop.

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.

A system for melting contaminant-laden solids that have been separated from a hydrocarbon-containing vapor stream in a hydrocarbon distillation tower, comprising at least one plate positioned where the solids form within the hydrocarbon distillation tower, hollow tubing forming an integral part of each of the at least one plate, and a heating medium disposed to flow through the hollow tubing at a higher temperature than a temperature of the solids to at least partially melt the solids.

A combined plant for cryogenic separation and liquefaction of methane and carbon dioxide in a biogas stream, including a mixing means, a compressor, a first exchanger, a distillation column, a second exchanger, a separating means, an expanding means, and a separator vessel. Wherein, the mixing means is configured such that the recycle gas is the overhead vapour stream, and the first exchanger and the expanding means are combined.

A combined plant for cryogenic separation and liquefaction of methane and carbon dioxide in a biogas stream, including a mixing means, a compressor, a first exchanger, a distillation column, a second exchanger, a separating means, an expanding means, and a separator vessel. Wherein the mixing means is configured such that the recycle gas is the overhead vapour stream, and the first exchanger and the expanding means are combined.

A heavies removal heat exchanger cools at least a portion of a feed gas stream. A scrubbing section receives the cooled main feed gas stream. A stripping section receives a fluid stream from the scrubbing section. A stripping gas feed expansion device receives a portion of the feed gas stream and is in fluid communication with the stripping section. A side draw vapor line receives a vapor stream from the vapor outlet of the stripping section and is in fluid communication with a reflux stream cooling passage of the heavies removal heat exchanger. A reflux separation device receives fluid from the heavies removal heat exchanger and has a liquid outlet and a vapor outlet. The liquid outlet is in fluid communication with the scrubbing section. A return vapor expansion device receives a vapor stream from the scrubbing section and directs a cooled vapor stream to a return vapor stream warming passage of the heavies removal heat exchanger. The reflux separation device vapor outlet is configured so that fluid passing therethrough joins with fluid that has exited the return vapor expansion device either before or after the fluid that has exited the return vapor expansion device flows through the return vapor stream warming passage of the heavies removal heat exchanger.

A thermally integrated separation method, including exchanging heat indirectly between an inlet stream and a liquid carbon dioxide/NGL containing stream in a heat exchanger, thereby producing a cold inlet stream and a vaporized carbon dioxide/NGL containing stream, introducing the cold inlet stream into a cryogenic separation unit, thereby producing the liquid carbon dioxide/NGL containing stream and a methane-rich stream, introducing the methane-rich stream into a membrane separation unit, thereby producing a methane rich product stream, and a permeate stream, and introducing the vaporized carbon dioxide/NGL containing stream into a carbon dioxide/NGL separation unit, thereby producing a carbon dioxide rich product stream and a NGL rich product stream. Wherein, at least a portion of the liquid carbon dioxide/NGL containing stream bypasses the heat exchanger and is introduced into the carbon dioxide/NGL separation unit in liquid phase.

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.