One or more specific embodiments disclosed herein includes a method for separating hydrogen from an olefin hydrocarbon rich compressed effluent vapor stream, employing a integrated heat exchanger, multiple gas-liquid separators, external refrigeration systems, and a rectifier attached to a liquid product drum.

A process for the separation of nitrogen from a feed stream containing at least methane and nitrogen, with a methane content between 4 and 12% mol. consists of at least the following steps: separation of the feed stream by means of a rubbery-type membrane to produce a permeate enriched in methane at a pressure greater than 2 bara and a non-permeate which is a nitrogen-enriched residue gas at a pressure greater than 2 bara and processing of the high-pressure residue gas in a cryogenic separation unit to produce a methane rich liquid and a nitrogen-enriched gas wherein the pressure of the membrane permeate is controlled as a function of the nitrogen concentration in the nitrogen-enriched gas.

A system for natural gas cooling using nitrogen. The system can include a nitrogen liquefier and a natural gas cooler. The nitrogen liquefier can provide liquid nitrogen to the natural gas cooler. One or more heat exchangers of the natural gas cooler can include a gaseous nitrogen output that is in fluid communication with the nitrogen liquefier. In response to receiving gaseous nitrogen at the nitrogen liquefier, from the one or more heat exchangers, a production rate of the the nitrogen liquefier is adjusted.

A process for obtaining a product gas and product LNG having pressure P1 close to the atmospheric pressure from lean LNG, includes: a) branching the lean LNG to obtain a first flow and a second flow; b) cooling the second flow by using a refrigerant; c) branching a liquid flow derived from the cooled second flow to obtain refrigerant LNG and remaining LNG; d) subjecting the remaining LNG to pressure reduction and gas-liquid separation to obtain a gas phase flow and a liquid phase flow (product LNG) having pressure P1; e) subjecting the refrigerant LNG to pressure reduction; f) using a flow from the step e as the refrigerant; g) joining, before or after the step f, the gas phase flow having pressure P1 to a flow from the step e; h) liquefying a flow resulting from the steps f and g by pressure increase and cooling (through heat exchange with the first flow); i) increasing the first flow in pressure before the step h; j) obtaining the product gas by regasifying the first flow after the steps h and i; and k) joining a flow liquefied in the step h to the second flow.

Described herein are methods and systems for producing liquefied natural gas (LNG) from a methane-containing synthetic gas (MCSG). An MCSG feed stream may be cooled and partially liquefied using one or more heat exchanger units. A first phase separator and a second phase separator in downstream fluid flow communication with the first phase separator may be used to separate the partially liquefied MCSG stream into a first residue gas stream and first and second feed streams, the first and second feed streams then being fed into a distillation column to produce an LNG stream and a second residue gas stream.

A process and an apparatus are disclosed for a compact processing assembly to improve the recovery of C.sub.2 (or C.sub.3) and heavier hydrocarbon components from a hydrocarbon gas stream. The preferred method of separating a hydrocarbon gas stream generally includes producing at least a substantially condensed first stream and a cooled second stream, expanding both streams to lower pressure, and supplying the streams to a fractionation tower. In the process and apparatus disclosed, the tower overhead vapor is directed to an absorbing means and a heat and mass transfer means inside a processing assembly. A portion of the outlet vapor from the processing assembly is compressed to higher pressure, cooled and substantially condensed in a heat exchange means inside the processing assembly, then expanded to lower pressure and supplied to the heat and mass transfer means to provide cooling. Condensed liquid from the absorbing means is fed to the tower.

The invention relates to a system, method and apparatus for processing natural gas in an LNG facility. A natural gas feed is introduced into a heavies removal unit. The heavies removal system includes a heavies removal column and a distillation column. The heavies removal column and the distillation column are connected via a purge/recovery line. One or more components of the natural gas feed is purged from the heavies removal column to the distillation column via the purge/recovery line to obtain a specified concentration or concentration range of heavy components feeding into the distillation column.

The present invention relates to a system (100) for supplying gas to at least one gas-consuming appliance (300) equipping a ship (70), the supply system (100) comprising at least: one gas supply line (123) for supplying gas to the at least one gas consuming appliance (300), said gas supply line being configured to be traversed by gas taken in the liquid state from a tank (200) and subjected to a pressure lower than a pressure of the gas in a headspace (201) of the tank (200), a first compression member (120) configured to compress the gas from the gas supply line (123) for supplying gas to the at least one gas-consuming appliance (300), a second compression member (130), characterised in that the first compression member (120) and the second compression member (130) alternately compress gas in the gaseous state from the gas supply line (123) and gas taken in the gaseous state from the headspace (201) of the tank (200).

A system includes a first separator that separates water from a fluid material. The water settles on the bottom of the water knock-out tank. The system includes multiple compressors to boost the pressure of the fluid material. The system includes a second separator that separates condensate from the fluid material. The system includes a mixing pipe that mixes glycol with the fluid material and a first heat exchanger that cools the mixed fluid material and glycol. The system includes a third separator that separates gaseous components and liquid components of the mixed fluid material and glycol and a fourth separator that separates the liquid components of the mixed fluid material and glycol. The system includes a fractional distillation column that heats a first liquid from the fourth separator, gasifying a first portion of the first liquid. A second portion of the first liquid remains liquid and is natural gas liquids.

A method and system for controlling the nitrogen concentration in an LNG product and fuel from flash gas within preferred ranges. A cooled LNG stream is separated into a nitrogen-enriched vapor stream, a fuel stream, and an LNG product stream using a plurality of phase separating devices, such as flash drum or rectifying column. A portion of the vapor stream is recycled to the rectifying column as reflux. A portion of a stream having a higher concentration of nitrogen is combined with the fuel stream to maintain the fuel stream within a desired nitrogen concentration range.