The amount of consumption of gas is reduced when the gas is expanded to be cooled by using a plurality of expansion turbines. A high-pressure expansion turbine includes: a gas supply passage through which bearing gas is supplied to a bearing portion; and a gas discharge passage through which the bearing gas which has been supplied from the gas supply passage to the bearing portion is discharged from the bearing portion. A low-pressure expansion turbine includes: a gas supply passage through which the bearing gas is supplied to a bearing portion; and a gas discharge passage through which the bearing gas which has been supplied from the gas supply passage to the bearing portion is discharged from the bearing portion. The bearing gas discharged from the gas discharge passage of the high-pressure expansion turbine is supplied to the gas supply passage of the low-pressure expansion turbine.

A raw material gas liquefying device includes a feed line; a refrigerant circulation line; and a controller. In a refrigerant liquefaction route, a refrigerant flows through a compressor, a heat exchanger, a circulation system JT valve, a liquefied refrigerant storage tank, and the heat exchanger, and returns to the compressor. In a cryogenic energy generation route, the refrigerant flows through the compressor, the heat exchanger, an expansion unit, and the heat exchanger, and returns to the compressor. The controller determines if a refrigerant storage tank liquid level is within an allowable range, manipulates a feed system JT valve opening rate to control refrigerant temperature at the high-temperature-side refrigerant flow path exit side of the heat exchanger, and manipulates the opening rate of the feed system JT valve to control the refrigerant storage tank liquid level so that the refrigerant storage tank liquid level falls into the predetermined allowable range.

A raw material gas liquefying device includes a feed line which feeds a raw material gas, a refrigerant circulation line which circulates a refrigerant, the refrigerant circulation line including an expansion unit of a turbine type which expands the refrigerant to generate cryogenic energy, and an expansion unit entrance valve provided at an entrance side of the expansion unit, a heat exchanger which exchanges heat between the raw material gas and the refrigerant, a cooler which performs initial cooling of the raw material gas and the refrigerant by heat exchange with liquid nitrogen, and a controller which manipulates the opening rate of the expansion unit entrance value and performs a feedback control so that the rotation speed of the expansion unit reaches a predetermined target value, and outputs the opening rate command to the expansion unit entrance valve, at start-up and stop of the expansion unit.

The present invention relates to a cryocooler suitable for gas liquefaction applications, that comprises a coldhead (1) with one or more refrigeration stages (2, 3); further comprising: a refrigerator compressor (4) for distributing compressed gas-phase cryogen inside the coldhead (1); a heat exchanging coil (9) arranged at least partially around the external region of the coldhead (1); at least one extraction orifice (8) communicating a gas circulation circuit (5) inside the coldhead (1) with the heat exchanging coil (9); acting said extraction orifice/s (8) as pass-through port/s which allow the gas inside the coldhead (1) to flow through the inside of the heat exchanger coil (9) for exchanging heat with the exterior thereof, and wherein the heat exchanging coil (9) is adapted to connect and redirect the gas to one return port (8) connected to the gas circulation circuit (5). Another object of the invention relates to a cryogen-gas liquefaction system (11) and a method for liquefaction of gases that comprises said system (11).

Cooling system, preferably adapted for use in or including a refrigeration plant and/or liquefier plant, having a refrigeration circuit (1) configured to use a refrigerant including a mixture of helium and neon; wherein the refrigerant is based on a raw mixture, preferably is the raw mixture, including helium and neon, extracted from air by an air separation plant (2). Method for producing a refrigerant usable in a refrigeration circuit (1), comprising: extracting a raw mixture including helium and neon from air, wherein the raw mixture preferably further includes nitrogen and hydrogen; and using the raw mixture as the refrigerant or obtaining the refrigerant from the raw mixture.

The amount of consumption of gas is reduced when the gas is expanded to be cooled by using a plurality of expansion turbines. A high-pressure expansion turbine includes: a gas supply passage through which bearing gas is supplied to a bearing portion; and a gas discharge passage through which the bearing gas which has been supplied from the gas supply passage to the bearing portion is discharged from the bearing portion. A low-pressure expansion turbine includes: a gas supply passage through which the bearing gas is supplied to a bearing portion; and a gas discharge passage through which the bearing gas which has been supplied from the gas supply passage to the bearing portion is discharged from the bearing portion. The bearing gas discharged from the gas discharge passage of the high-pressure expansion turbine is supplied to the gas supply passage of the low-pressure expansion turbine.

Device and method for purifying a gas mixture to produce a concentrated gas, notably neon, starting from a mixture comprising neon, said device including, in a cold box housing a cryogenic purification circuit comprising, in series, at least one unit for purifying the mixture by cryogenic adsorption at a temperature between 65K and 100K and notably 65K, then a unit for cooling the mixture to a temperature between 25 and 65 K and then a unit for cryogenic distillation of the mixture to produce the concentrated liquid at the outlet of the cryogenic distillation unit, characterized in that the unit for cooling the mixture to a temperature between 25 and 65 K comprises at least one cryocooler that extracts thermal power from the mixture via a heat exchanger.

An arrangement comprising at least one liquefaction plant for liquefying a gaseous medium to produce a liquefied medium; and at least one storage tank for storing the liquefied medium. A first transfer line is provided which is connected between the liquefaction plant and the storage tank, for transferring liquefied medium from the liquefaction plant into the storage tank. A second transfer line is connected between the liquefaction plant and the storage tank, for transferring gaseous medium from the storage tank into the liquefaction plant. The second transfer line, which used for transferring medium from the storage tank into the liquefaction plant, is arranged so that it is routed at least partially through the area of the storage tank in which the liquefied medium is stored in use.

A method of cooling a process stream with an auxiliary stream is described, wherein the exchange of heat between the process stream and the auxiliary stream is effected in a first heat exchanger and a second heat exchanger connected downstream thereof.

A raw material gas liquefying device includes a feed line which feeds a raw material gas, a refrigerant circulation line which circulates a refrigerant, the refrigerant circulation line including an expansion unit of a turbine type which expands the refrigerant to generate cryogenic energy, and an expansion unit entrance valve provided at an entrance side of the expansion unit, a heat exchanger which exchanges heat between the raw material gas and the refrigerant, a cooler which performs initial cooling of the raw material gas and the refrigerant by heat exchange with liquid nitrogen, and a controller which manipulates the opening rate of the expansion unit entrance value and performs a feedback control so that the rotation speed of the expansion unit reaches a predetermined target value, and outputs the opening rate command to the expansion unit entrance valve, at start-up and stop of the expansion unit.