Integrated systems are provided for the production of higher hydrocarbon compositions, for example liquid hydrocarbon compositions, from methane using an oxidative coupling of methane system to convert methane to ethylene, followed by conversion of ethylene to selectable higher hydrocarbon products. Integrated systems and processes are provided that process methane through to these higher hydrocarbon products.

Described herein is a method of removing refrigerant from a natural gas liquefaction system in which vaporized mixed refrigerant is withdrawn from the closed-loop refrigeration circuit and introduced into a distillation column so as to be separated into an overhead vapor enriched in methane and a bottoms liquid enriched in heavier components. Overhead vapor is withdrawn from the distillation column to form a methane enriched stream that is removed from the liquefaction system, and bottoms liquid is reintroduced from the distillation column into the closed-loop refrigeration circuit. Also described are methods of altering the rate of production in a natural gas liquefaction system in which refrigerant is removed as described above, and a natural gas liquefaction systems in which such methods can be carried out.

A process and a related equipment for making ammonia make-up synthesis gas are disclosed, where: a hydrocarbon feedstock is reformed obtaining a raw ammonia make-up syngas stream; said raw syngas is purified in a cryogenic purification section refrigerated by a nitrogen-rich stream produced in an air separation unit; the nitrogen-rich stream at output of said cryogenic section is further used for adjusting the hydrogen/nitrogen ratio of the purified make-up syngas; an oxygen-rich stream is also produced in said air separation unit and is fed to the reforming section.

A method for low-temperature air separation, in which an air-separation system having a column system is used that has a first column, a second column, a third column, and a fourth column, wherein fluid from the first column is fed at least into the second column, fluid from the second column is fed at least into the third column, fluid from the third column is fed at least into the fourth column, and fluid from the fourth column is fed at least into the third column, and wherein the fluid fed from the third column into the fourth column includes at least a portion of a side flow, which is withdrawn from the third column and has a lower oxygen content and a higher argon content than the third sump liquid. The present invention also relates to a corresponding system.

The present disclosure provides oxidative coupling of methane (OCM) systems for small scale and world scale production of olefins. An OCM system may comprise an OCM subsystem that generates a product stream comprising C.sub.2+ compounds and non-C.sub.2+ impurities from methane and an oxidizing agent. At least one separations subsystem downstream of, and fluidically coupled to, the OCM subsystem can be used to separate the non-C.sub.2+ impurities from the C.sub.2+ compounds. A methanation subsystem downstream and fluidically coupled to the OCM subsystem can be used to react H.sub.2 with CO and/or CO.sub.2 in the non-C.sub.2+ impurities to generate methane, which can be recycled to the OCM subsystem. The OCM system can be integrated in a non-OCM system, such as a natural gas liquids system or an existing ethylene cracker.

A set of process equipment for use in an enhanced oil recovery (EOR) process comprises first piping, a dehydrator, second piping, and a natural gas liquids recovery column. The first piping is configured to receive a wet carbon dioxide recycle stream from a recovery well. The dehydrator is configured to receive the wet carbon dioxide stream from the first piping and configured to dehydrate the wet carbon dioxide recycle stream using ethylene glycol to produce a dry carbon dioxide recycle stream. The second piping is configured to receive the dry carbon dioxide recycle stream from the dehydrator. The natural gas liquids recovery column is configured to receive the dry carbon dioxide recycle stream from the second piping and configured to separate the dry carbon dioxide recycle stream into a carbon dioxide reinjection stream and a natural gas liquids stream.

Light gases such as helium are extracted from a carbon dioxide-containing feed stream by distillation. Costly dehydration steps are avoided by pumping the liquid bottoms stream leaving the distillation column without vaporization so as to ensure that any water present in the feed remains in solution with the bulk stream leaving the process. This prevents any liquid phase water causing corrosion or solid ice or hydrates forming to plug the flow.

Methods and systems for processing natural gas to meet gas pipeline specifications and/or recovering natural gas liquids (NGL). The natural gas is cooled and distilled such that propane and heavier components are produced as a bottoms NGL product, and inerts, methane, ethane, and other lighter portions are produced as a fuel gas grade/quality residue gas product stream. The gas can optionally be treated to remove hydrogen-sulfide and/or carbon dioxide. The NGL product can be split into a marketable propane and butane liquefied petroleum gas (LPG) liquid product and a natural gas condensate product.

Methods and systems for operating and NGL recovery process are provided. In an exemplary method, an absorber column upstream of a fractionator column is operated at a higher pressure than a pressure in the fractionator column. An NGL (C.sub.3 plus) stream is taken from the bottom of a fractionator column and then ethylene/ethane stream is taken from the top of the fractionator column. A differential pressure between the absorber column and the fraction are column is controlled based, at least in part, on a flow rate of the fractionator feed stream from the absorber column to the fractionator column.

The invention relates to a system, method and apparatus for removing heavies from natural gas. Natural gas and an external rich reflux gas feed are processed in a single column refluxed absorber. A bottoms stream is routed to a first heat exchanger and then to a stabilizer column where an overhead stream from the stabilizer column is routed through a condenser for partial separation into an overhead stream. A rich solvent may be introduced to the stabilizer column. The overhead stream is routed through a condenser for partial separation into a stabilizer reflux and a second overhead stream lights. The second overhead stream lights is routed to a heat exchanger and then routed to a partial condenser where the stream is separated into a heavies rich reflux stream, a distillate stream and heavies treated natural gas stream. The rich reflux is routed through a heat exchanger and the rich reflux is pumped to the single column refluxed absorber to be introduced into the single column refluxed absorber as the external rich reflux gas feed.