Integration of a natural gas liquefaction system, a hydrogen production system, and power generation system to increase CO2 capture and improve overall plant efficiency. The predominantly methane endflash is sent to the hydrogen production system which produces hydrogen and CO2. The CO2 may be captured or beneficially used. At least a portion of the hydrogen produced is used to fuel gas turbines in the power generation which, in turn, provides power for the refrigeration compressor of the natural gas liquefaction system—either in the form of mechanical work or electricity.

A process and an apparatus are disclosed for separation of a hydrocarbon gas stream containing methane and heavier hydrocarbons and significant quantities of nitrogen and carbon dioxide. The gas stream is cooled and expanded, then fractionated in a first distillation column into a first overhead vapor and a hydrocarbon liquid stream containing the majority of the carbon dioxide. The hydrocarbon liquid stream is fractionated into a hydrocarbon vapor stream and a less volatile fraction comprised of heavier hydrocarbons. The first overhead vapor is cooled, expanded, and separated into vapor and liquid streams. Both streams are cooled and expanded before feeding a second distillation column that produces a second overhead vapor that is predominantly nitrogen and a bottom liquid that is predominantly methane. The bottom liquid is vaporized and combined with the hydrocarbon vapor stream to form a volatile residue gas fraction containing the majority of the methane.

A process for producing biomethane by scrubbing a biogas feed stream includes introducing the feed gas stream into a pretreatment unit wherein a CO.sub.2-depleted gas stream is partially separated from a CO.sub.2 stream and an oxygen stream and is compressed to a pressure P1 above 25 bar abs. Subjecting the CO.sub.2-depleted gas stream to cryogenic separation in a distillation column to separate a nitrogen stream and produce a CH.sub.4-enriched stream, the distillation column comprising n plates, n being an integer between 8 and 100. Recovering a pressurized CH.sub.4-enriched stream by pumping the CO.sub.2-depleted gas stream to a pressure P2 above 25 bar absolute.

Devices, systems, and methods for liquefied natural gas production facilities are disclosed herein. A liquefied natural gas (LNG) production facility includes a liquefaction unit and a gas turbine. The liquefaction unit condenses natural gas vapor into liquefied natural gas. Fuel to the gas turbine contains at least about 90% hydrogen by volume.

A method and system for liquefying a methane-rich high-pressure feed gas stream using a first heat exchanger zone and a second heat exchanger zone. The feed gas stream is mixed with a refrigerant stream to form a second gas stream, which is compressed, cooled, and directed to a second heat exchanger zone to be additionally cooled below ambient temperature. It is then expanded to a pressure less than 2,000 psia and no greater than the pressure to which the second gas stream was compressed, and then separated into a first expanded refrigerant stream and a chilled gas stream. The first expanded refrigerant stream is expanded and then passed through the first heat exchanger zone such that it has a temperature that is cooler, by at least 5° F., than the highest fluid temperature within the first heat exchanger zone.

Devices, systems, and methods for liquefied natural gas production facilities are disclosed herein. A liquefied natural gas (LNG) production facility includes a liquefaction unit that condenses natural gas vapor into liquefied natural gas; an electric-driven compression system for the refrigerant(s) in power to the liquefaction unit; and a sequestration compression unit configured to compress and convey at least one CO2-rich stream towards a sequestration site, thereby reducing the overall emissions from the LNG facility.

Devices, systems, and methods for liquefied natural gas production facilities are disclosed herein. A liquefied natural gas (LNG) production facility includes a liquefaction unit and a gas turbine. The liquefaction unit condenses natural gas vapor into liquefied natural gas. Fuel to the gas turbine contains at least about 90% hydrogen by volume.

Devices, systems, and methods for liquefied natural gas production facilities are disclosed herein. A liquefied natural gas (LNG) production facility includes a liquefaction unit, a gas turbine, and a hydrogen generation unit. The liquefaction unit condenses natural gas vapor into liquefied natural gas. The hydrogen generation unit generates hydrogen. At least a portion of the hydrogen formed in the hydrogen generation unit is combusted, along with hydrocarbons, as fuel in the gas turbine.

Devices, systems, and methods for liquefied natural gas production facilities are disclosed herein. A liquefied natural gas (LNG) production facility includes a liquefaction unit, a gas turbine, and a hydrogen generation unit. The liquefaction unit condenses natural gas vapor into liquefied natural gas. The hydrogen generation unit generates hydrogen. At least a portion of the hydrogen formed in the hydrogen generation unit is combusted, along with hydrocarbons, as fuel in the gas turbine.

A method for producing liquefied natural gas (LNG) from a natural gas stream having a nitrogen concentration of greater than 1 mol %. At least one liquid nitrogen (LIN) stream is received at an LNG liquefaction facility. The LIN streams may be produced at a different geographic location from the LNG liquefaction facility. A natural gas stream is liquefied by indirect heat exchange with a nitrogen vent stream to form a pressurized LNG stream. The pressurized LNG stream has a nitrogen concentration of greater than 1 mol %. The pressurized LNG stream is directed to one or more stages of a column to produce an LNG stream and the nitrogen vent stream. The column has upper stages and lower stages. The LIN streams are directed to one or more upper stages of the column.