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.

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.

A gas processing system according to an embodiment of the present invention controls inflow fuel pressure of a low pressure demand source according to an operation or a non-operation of a high pressure demand source and the low pressure demand source.

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.

Disclosed is a method of discharging lubricant oil from a BOG reliquefaction system configured to reliquefy BOG by compressing the BOG by a compressor, cooling the compressed BOG through heat exchange with non-compressed BOG by a heat exchanger, and reducing a pressure of fluid cooled through heat exchange by a pressure reducer. In the lubricant oil discharge method, the compressor comprises at least one oil-lubrication type cylinder and it is determined that it is time to discharge condensed or solidified lubricant oil, if at least one of preset conditions is satisfied.

The invention relates to a gas treatment method and system of a gas storage facility (2), in particular on board a ship, the method comprising the following stages: an extraction of a first gas (4a, 4b, 5a, 5b,) in the liquid state from a first tank (4) or first vessel (5; 500), a first subcooling of the first gas in the liquid state, and storage of the subcooled first gas in the liquid state in the lower part of the first tank (4) or of the first vessel (5; 500) or of a second tank or of a second vessel, so as to constitute a reserve layer of cold (4c, 5c, 500c) of the subcooled first gas in the liquid state at the bottom of the first or second tank (4) or of the first or second vessel (5; 500).

Disclosed is a BOG reliquefaction system. The BOG reliquefaction system includes: a compressor compressing BOG; a heat exchanger cooling the BOG compressed by the compressor through heat exchange using BOG discharged from a storage tank as a refrigerant; a bypass line through which the BOG is supplied to the compressor after bypassing the heat exchanger; a second valve disposed on a second supply line through which the BOG used as the refrigerant in the heat exchanger is supplied to the compressor, the second valve regulating a flow rate of fluid and opening/closing of the second supply line; and a pressure reducer disposed downstream of the heat exchanger and reducing a pressure of fluid cooled by the heat exchanger, wherein the compressor includes at least one oil-lubrication type cylinder and the bypass line is joined to the second supply line downstream of the second valve.

A synthesis gas production process combined with a natural gas liquefaction process. At least one part of the heat source required in the synthesis gas production is provided by at least one portion of a stream enriched in hydrocarbons with more than two carbon atoms, extracted during the liquefaction of the natural gas.

A method for large-scale, air-cooled floating liquefaction, storage and offloading of natural gas gathered from onshore gas pipeline networks. Gas gathered from on-shore pipeline quality gas sources and pre-treated to remove unwanted compounds is compressed and cooled onshore before being piped to an offshore vessel for liquefaction to produce LNG.

A method for producing an LNG from natural gas, comprising liquefaction of at least a first part of the natural gas in a first heat exchanger by heat exchange with a first mixed refrigerant fluid in a closed cycle, sub-cooling of liquefied natural gas in a second heat exchanger by heat exchange with a second refrigerant fluid of a second refrigeration cycle, expansion of the sub-cooled liquefied natural gas stream and admission into a flash gas separator, withdrawal of liquefied natural gas at the bottom of the separator, and withdrawal, at the head, of a gas flow, and supply of the second refrigeration cycle by at least a part of said gas flow.