A proposed method for thermally assisted electric energy storage is intended for increase in round-trip efficiency through recovery of waste heat energy streams from the co-located power generation and industrial facilities, combustion of renewable or fossil fuels, or harnessing the renewable energy sources. In the charge operation mode, it is achieved by superheating and expansion of recirculating air stream in the liquid air energy storage with self-producing a part of power required for air liquefaction. In the discharge operation mode, it is attained through the repeated use of a stream of discharged air for production of an additional power in auxiliary discharge cycle.

A power supply and cooling system for a floating structure having a tank, includes a supply circuit having at least one compression device, the supply circuit being configured to supply gas to a gas-consuming device, and a cooling circuit having a heat exchanger configured to participate in managing the internal pressure of the tank, the cooling circuit being connected to the supply circuit on either side of the compression device. The compression device includes two compression stages, and the power supply and cooling system includes a control device configured to connect the compression stages in series or in parallel.

A liquefaction system comprises: a temperature setting unit for setting an inlet gas temperature on entry to a cold turbine; a control valve for controlling an amount of gas fed to the cold turbine, correspondingly with an inlet gas temperature measured by the temperature measuring unit; and a control unit which compares the inlet gas temperature measured by the temperature measuring unit with a warning temperature set value plus a margin, and sets a first operating state when the inlet gas temperature is equal to or less than the warning temperature set value plus the margin and also sets an emergency stoppage temperature set value at the warning temperature set value plus the margin, and sets a second operating state when the inlet gas temperature is greater than the warning temperature set value plus the margin, the control unit performing control in response to the second operating state to make a degree of opening of the control valve greater than a degree of opening during the first operating state in order to lower an inlet pressure of the cold turbine, and performing control in response to the first operating state to make the degree of opening of the control valve smaller than the degree of opening during the second operating state in order to raise the inlet pressure of the cold turbine.

The disclosure describes processes which include cooling a natural gas product stream to a cryogenic liquid storage temperature by way of refrigeration streams which include a primary refrigeration stream, a secondary refrigeration stream, and a tertiary refrigeration stream in a refrigeration system. After leaving the refrigeration system, the pressure of each refrigeration stream is increased, and upon reaching a sufficient pressure, the refrigeration streams are recycled to flow back into the refrigeration system as a recycle stream. The disclosure further describes systems capable of performing the processes. The processes and systems can include one or more sensors and one or more controls capable of adjusting a flow rate, flow volume, and/or flow ratio among one or more gas streams to maximize cooling efficiency based on monitoring from the one or more sensors. Mobile natural gas liquefaction systems are also described.

A system and method for producing liquefied natural gas are provided. The method may include compressing a process stream containing natural gas in a compression assembly to produce a compressed process stream. The method may also include removing non-hydrocarbons from the compressed process stream in a separator, and cooling the compressed process stream with a cooling assembly to thereby produce a cooled, compressed process stream containing natural gas in a supercritical state. The method may further include expanding a first portion and a second portion of the natural gas from the cooled, compressed process stream in a first expansion element and a second expansion element to generate a first refrigeration stream and a second refrigeration stream, respectively. The method may further include cooling the natural gas in the cooled, compressed process stream to a supercritical state with the first and second refrigeration streams to thereby produce the liquefied natural gas.

Disclosed is a device for refrigerating or liquefying a fluid such as natural gas or hydrogen, comprising a fluid circuit that is to be cooled and has an upstream end for connection to a source of gaseous fluid as well as a downstream end for connection to a member for collecting the cooled or liquefied fluid, the device comprising a heat exchanger assembly in heat exchange with the fluid circuit to be cooled, the device comprising a refrigerator in heat exchange with at least a portion of the exchanger assembly, the refrigerator being of the type that has a cycle for refrigerating a cycle gas containing at least one of: helium, hydrogen, nitrogen or neon; said refrigerator comprising in series in a cycle circuit: a mechanism for compressing the cycle gas, at least one member for cooling the cycle gas, a mechanism for expanding the cycle gas, and at least one member for reheating the expanded cycle gas, wherein the compression mechanism comprises a plurality of compression stages in series composed of a centrifugal compressor assembly, the compression stages being mounted on a set of shafts that are rotationally driven by a motor assembly, the at least one member for cooling the cycle gas comprising at least one heat exchanger at the outlet of at least one compression stage in heat exchange with the cycle circuit, said heat exchanger being cooled by a heat transfer fluid, characterized in that the compression mechanism comprises at least two compression stages that are arranged successively in series and do not include any member for cooling the cycle gas such as a heat exchanger therebetween.

Disclosed is a device for liquefying a fluid, comprising a fluid circuit to be cooled, the device comprising a heat exchanger assembly in heat exchange with the fluid circuit to be cooled, at least one first cooling system in heat exchange with at least a portion of the heat exchanger assembly, the first cooling system being a refrigerator having a cycle for refrigerating a cycle gas mainly comprising helium, said refrigerator comprising in series in a cycle circuit: a mechanism for compressing the cycle gas, at least one member for cooling the cycle gas, a mechanism for expanding the cycle gas, and at least one member for reheating the expanded cycle gas, wherein the compression mechanism includes at least four compression stages in series composed of a centrifugal compressor assembly, the compression stages being mounted on shafts that are rotationally driven by a motor assembly, the expansion mechanism comprising at least three expansion stages in series composed of a set of centripetal turbines, the at least one member for cooling the cycle gas being configured to cool the cycle gas at the outlet of at least one of the turbines, and wherein at least one of the turbines is coupled to the same shaft as at least one compression stage so as to feed the mechanical work produced during the expansion to the compression stage.

Described herein are methods and systems for removing natural gas liquids from a natural gas feed stream and for liquefying the natural gas feed stream so as to produce a liquefied natural gas (LNG) stream and a natural gas liquids (NGL) stream

Disclosed is a device for refrigerating or liquefying a fluid such as natural gas or hydrogen, comprising a circuit for fluid that is to be cooled and has an upstream end for connection to a source of gaseous fluid and a downstream end for connection to a member for collecting the cooled or liquefied fluid, the device comprising a heat exchanger assembly in heat exchange with the circuit of fluid to be cooled, the device comprising a refrigerator in heat exchange with at least a portion of the heat exchanger assembly, the refrigerator being of the type that has a cycle for refrigerating a cycle gas containing at least one of: helium, hydrogen, nitrogen or neon; said refrigerator comprising, arranged in series in a cycle circuit: a mechanism for compressing the cycle gas, at least one member for coding the cycle gas, a mechanism for expanding the cycle gas, and at least one member for reheating the expanded cycle gas, wherein the compression mechanism comprises a plurality of compression stages in series composed of a centrifugal compressor assembly, the compression stages being mounted on a set of shafts rotated by an assembly of one or more motors, the at least one member for cooling the cycle gas comprising at least one heat exchanger arranged at the outlet of at least one compression stage in heat exchange with the cycle circuit, said heat exchanger being cooled by a heat-transfer fluid, characterized in that the compression mechanism comprises at least two compression stages that are arranged successively in series and do not include any member for cooling the cycle gas such as a heat exchanger therebetween.

Disclosed is a device for refrigerating or liquefying a fluid such as natural gas or hydrogen, comprising a fluid circuit that is to be cooled and has an upstream end for connection to a source of gaseous fluid as well as a downstream end for connection to a member for collecting the cooled or liquefied fluid, the device comprising a heat exchanger assembly in heat exchange with the fluid circuit to be cooled, the device comprising a refrigerator in heat exchange with at least a portion of the exchanger assembly, the refrigerator being of the type that has a cycle for refrigerating a cycle gas containing at least one of: helium, hydrogen, nitrogen or neon; said refrigerator comprising in series in a cycle circuit: a mechanism for compressing the cycle gas, at least one member for cooling the cycle gas, a mechanism for expanding the cycle gas, and at least one member for reheating the expanded cycle gas, wherein the compression mechanism comprises a plurality of compression stages in series composed of a centrifugal compressor assembly, the compression stages being mounted on a set of shafts that are rotationally driven by a motor assembly, the at least one member for cooling the cycle gas comprising at least one heat exchanger at the outlet of at least one compression stage in heat exchange with the cycle circuit, said heat exchanger being cooled by a heat transfer fluid, characterized in that the compression mechanism comprises at least two compression stages that are arranged successively in series and do not include any member for cooling the cycle gas such as a heat exchanger therebetween.