A first turboexpander generator is configured to decrease a temperature or pressure of a process stream flowing through the first turboexpander generator by generating electrical power from the process stream. A second turboexpander generator is configured to decrease a temperature or pressure of a process stream flowing through the second turboexpander generator by generating electrical power from the process stream. The second turboexpander generator is downstream of and receives a flow output from the first turboexpander generator. The first turboexpander generator and the second turboexpander generator each include the following features. An electric stator surrounds an electric rotor. An annulus defined by the electric rotor and the electric stator is configured to receive a process fluid flow. Magnetic bearings carry the rotor within the stator. A housing encloses the rotor and stator. The housing is hermetically sealed between an inlet and an outlet of each turboexpander generator.

Provided herein are systems and methods for utilizing a natural gas letdown generator at a natural gas regulating station. The system utilizes the gas letdown generator to generate electricity by converting high pressure inlet gas to low pressure outlet gas, which in turn creates low temperature outlet gas. Electricity generated can power a data center. Heat may be transferred, using a heat exchanger, from dielectric fluid of the data center to the natural gas prior to entering the gas letdown generator. Heat may be further transferred, using a second heat exchanger, from the dielectric fluid to the natural gas at the output of the gas letdown generator. The heat exchange may substantially cool the dielectric fluid for transmission to the data center and may heat the low temperature outlet gas for transmission to an end user.

An apparatus for the separation or liquefaction of a gas at cryogenic temperatures which comprises an isolated chamber comprises at least one front distillation column operating at cryogenic temperatures and also a pipe for transferring fluid coming from or going to the column, the pipe having a diameter D comprising a bend for changing the direction of flow of the fluid, with profiled deflector vanes placed inside the bend, with their concavity towards the centre of the bend forming a plurality of ducts.

The present invention corresponds to a gas cooling and condensing system using fluid energy and comprising a gas feed line, a first vortex tube connected to the gas feed line, a second vortex tube connected to the first vortex tube and a first heat exchanger connected to the second vortex tube and to the gas feed line. Said gas cooling and condensing system is a modular system, which may be replicated and connected in series or in parallel to another modular system to obtain a cooler or higher mass flow gas than that obtained with a single modular system.

Moreover, the system of the present invention is optionally connected to thermal recovery, pressure recovery, recirculation or venting elements for the utilization of the waste gas streams. Furthermore, the system of the present invention does not require additional energy to that obtained from the pressure of the feed line for obtaining liquefied gas. On the other hand, the system of the present invention taps the pressure drop required between the compressed gas transport and distribution activities.

A method for exhaust waste energy recovery at the reciprocating gas engine-based polygeneration plant which includes supplying this plant with any on-site available methaneous gas, converting from 15 to 30% of supplied gas into electric or mechanical power and producing a liquefied methaneous gas (LMG) co-product from the other 85-70% of supplied gas, and thereby obviates a need for any specialized refrigeration equipment, refrigerants and fuel for LMG co-production at a rate of 0.4-0.6 ton/h for each MW of engine output and makes possible to increase the LMG co-production rate up to 0.9-1.1 t/MWh at the sacrifice of a fuel self-consumption minimized down to 1-2% of the amount of gas intended for liquefaction.

An apparatus for the separation or liquefaction of a gas at cryogenic temperatures which comprises an isolated chamber comprises at least one front distillation column operating at cryogenic temperatures and also a pipe for transferring fluid coming from or going to the column, the pipe having a diameter D comprising a bend for changing the direction of flow of the fluid, with profiled deflector vanes placed inside the bend, with their concavity towards the centre of the bend forming a plurality of ducts.

Systems and processes for natural gas processing, liquefaction, and storage are described. The systems and processes include one or more arrangements of features which are capable of liquefying all of the gas entering an inlet of the system or a portion of the entering gas. The portion of the entering gas that is liquefied can vary based on the pressure of an outlet of the system, which can be fixed or vary based on usage downstream.

An apparatus, system and method for reliquefaction of previously regasified LNG are described. A natural gas reliquefaction method includes regasifying LNG onboard a FSRU to form high pressure regasified LNG (HP RLNG), delivering the HP RLNG to a natural gas pipeline that commingles with a natural gas grid, flowing the HP RLNG through a lateral, wherein the lateral diverts HP RLNG from the natural gas pipeline to an expander prior to commingling with the natural gas grid, expanding the natural gas with the expander to obtain low pressure regasified LNG (LP RLNG), liquefying the LP RLNG in a cold box of a nitrogen expansion loop to produce low pressure LNG, and transmitting the LNG to a cryogenic cargo tank onboard an LNG tanker truck.

There is described a method to produce LNG at gas pressure letdown stations. A high pressure gas stream is pre-cooled, dewatered, and then divided into two streams: a diverted LNG production stream (LNG stream) and a gas to end users stream (User stream). Carbon dioxide is removed from the LNG stream and the LNG stream is compressed. The LNG stream is then precooled by passing through one or more heat exchangers. Hydrocarbon condensate is removed from the LNG steam by passing the LNG stream through a first Knock Out drum. The LNG stream is then depressured by passing through a JT valve to depressurize the gas vapour exiting the first Knock Out drum and discharge it into a second Knock Out drum where the LNG is captured.

A method for exhaust waste energy recovery at the reciprocating gas engine-based polygeneration plant which includes supplying this plant with any on-site available methaneous gas, converting from 15 to 30% of supplied gas into electric or mechanical power and producing a liquefied methaneous gas (LMG) co-product from the other 85-70% of supplied gas, and thereby obviates a need for any specialized refrigeration equipment, refrigerants and fuel for LMG co-production at a rate of 0.4-0.6 ton/h for each MW of engine output and makes possible to increase the LMG co-production rate up to 0.9-1.1 t/MWh at the sacrifice of a fuel self-consumption minimized down to 1-2% of the amount of gas intended for liquefaction.