Systems and processes for upgrading natural gas liquids (NGL). A natural gas, preferably a shale gas, comprising methane and one or more natural gas liquids can be converted to one or more liquid hydrocarbons. Methane can be separated from the one or more liquid hydrocarbons using a liquid absorbent to provide a first separated stream comprising the methane from the converted stream and a second separated stream comprising the one or more liquid hydrocarbons from the converted stream. At least a portion of the one or more liquid hydrocarbons can be recycled as the liquid absorbent.

A hydrogen liquefaction apparatus according to the present disclosure comprises a compressor located on a hydrogen flow path to perform the first isothermal process; a precooler, a heat exchanger, and a first cryocooler which are connected to the compressor on the hydrogen flow path in this order to perform the first isobaric process; a Joule-Thomson valve connected to the first cryocooler on the hydrogen flow path to perform the isenthalpic process; a storage tank connected to the Joule-Thomson valve on the hydrogen flow path to perform the second isothermal process; and second cryocoolers which are connected to the storage tank on the hydrogen flow path to perform the third isobaric process between the isenthalpic process and the second isothermal process.

An equipment for manufacturing liquid hydrogen according to the present disclosure, which is configured to perform the first isothermal process, the first isobaric process, the isenthalpic process, the second isothermal process, and the second isobaric process in the diagram of temperature T and enthalphy S for liquefying gaseous hydrogen, comprises: a compressor located on a hydrogen flow path to perform the first isothermal process; a precooler and a heat exchanger which are connected to the compressor, on the hydrogen flow path, in this order to perform the first isobaric process; a Joule-Thomson valve connected to the heat exchanger, on the hydrogen flow path, to perform the isenthalpic process; a first cryocooler and second cryocoolers connected to the Joule-Thomson valve sequentially, on the hydrogen flow path, to perform the third isobaric process between the isenthalpic process and the second isothermal process; and a storage tank which is connected to the first cryocooler and the second cryocoolers to perform the second isothermal process on the hydrogen flow path.

Plant and method for producing hydrogen at cryogenic temperature, in particular liquefied hydrogen, comprising: an electrolyzer having an oxygen outlet and a hydrogen outlet; a hydrogen circuit to be cooled, comprising an upstream end connected to the hydrogen outlet and a downstream end to be connected to a member for collecting cooled and/or liquefied hydrogen, the plant also comprising a set of heat exchanger(s) in heat exchange with the hydrogen circuit to be cooled, the plant further comprising at least one cooling device in heat exchange with at least a portion of the set of heat exchanger(s), the hydrogen circuit to be cooled comprising a system for expanding the hydrogen stream and at least one hydrogen compressor upstream of the hydrogen stream expansion system, the hydrogen stream expansion system comprising at least one expansion turbine, wherein said at least one expansion turbine and said at least one compressor are coupled to the same rotating shaft to transfer expansion work from the pressurized hydrogen stream to the compressor in order to compress the hydrogen stream upstream of the turbine.

The present invention relates to a method for liquefying hydrogen, the method comprises the steps of: cooling a feed gas stream comprising hydrogen with a pressure of at least 15 bar(a) to a temperature below the critical temperature of hydrogen in a first cooling step yielding a liquid product stream. According to the invention, the feed gas stream is cooled by a closed first cooling cycle with a high pressure first refrigerant stream comprising hydrogen, wherein the high pressure first refrigerant stream is separated into at least two partial streams, a first partial stream is expanded to low pressure, thereby producing cold to cool the precooled feed gas below the critical pressure of hydrogen, and compressed to a medium pressure, and wherein a second partial stream is expanded at least close to the medium pressure and guided into the medium pressure first partial stream.

The system for treating a gas deriving from the evaporation of a cryogenic liquid and supplying pressurized gas to a gas engine according to the invention comprises, on the one hand, from upstream to downstream, a reliquefaction unit (10) with compression means (11, 12, 13), a first heat exchanger (17) and expansion means (30), and, on the other hand, a pressurized gas supply line comprising, from upstream to downstream, a pump (48) for pressurizing the liquid and high-pressure vaporization means (61). The pressurized gas supply line has, upstream of the vaporization means (61), a bypass (57) for supplying a second heat exchanger (60) between, on the one hand, pressurized liquid of the supply line (56) and, on the other hand, a line (22) of the reliquefaction unit (10) downstream of the first exchanger and upstream of the expansion means (30).

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

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

In a propane dehydrogenation (PDH) process, the purpose of the deethanizer and chilling train systems is to separate the cracked gas into a methane-rich tail gas product, a C2, and a C3 process stream. By the use of staged cooling, process-to-process inter-change against propane feed to the reactor and use of high efficiency heat exchangers and distributed distillation techniques, refrigeration power requirements are reduced and a simple and reliable design is provided by the process described herein.

A method and apparatus for producing liquefied natural gas. A portion of a natural gas stream is cooled in a first heat exchanger and re-combined with the natural gas stream, and heavy hydrocarbons are removed therefrom to generate a separated natural gas stream and a separator bottom stream. Liquids are separated from the separator bottom stream to form an overhead stream, which is cooled and separated to form a recycle gas stream. The recycle gas stream is compressed. A first portion of the compressed recycle gas stream is directed through the first heat exchanger and directed to the separator as a column reflux stream. The separated to natural gas stream is used as a coolant in the first heat exchanger to thereby generate a pretreated natural gas stream, which is compressed and liquefied.