An operation analysis method for a natural gas plant includes: acquiring production amount data of a product per unit time and operation data of a plurality of controlled devices forming the natural gas plant in association with each other along a time series; determining whether or not a controlled device that violates the operation constraint is present at the time point of acquisition of the production amount data when the production amount data is less than the reference production amount, and performing data processing of associating an item subjected to the operation constraint to the production amount data; and determining, for each of the items subjected to the operation constraints, a length of a period with the production reduction in accordance with a magnitude of the production reduction amount.

Contaminants are removed from a raw natural gas stream and other types of mixed-gas streams by a separation system. The system is based on using a series of cryogenic cells, devices that can impose essentially any desired temperature and pressure conditions on a volume of incoming gas, down to cryogenic temperatures and up to multiple atmospheres of pressure. Used in succession at specific setpoints of temperature and pressure, the cryogenic cells cause gaseous contaminants in the raw gas stream to condense into liquid form, at which point, they can be separated from the stream. Flowmeters and component detectors, like mass spectrometers, are used to detect the state of the gas stream at various points in the system. The system may be divided into stages, each stage having cryogenic cells operating at different setpoints of temperature and pressure, in order to cause different contaminants to liquefy for separation.

The present disclosure provides a gas liquefaction separator, a gas liquefaction recovery system, and a method for separating and recovering ethylene oxide. The gas liquefaction separator includes a housing, a blocking plate, a gas baffle, and a liquid collector, the latter three being located inside the housing. The liquid collector—an outer edge of which is connected to an inner wall of the housing—is located below the gas baffle, which is located below the blocking plate. The liquid collector includes a first flow guide surface, on a bottom portion of which is disposed a first hole. The gas baffle—an upper surface of which forms a second flow guide surface and an outer edge of which has a protrusion(s)—is connected to the first flow guide surface through the protrusion(s), thereby forming a second hole between the outer edge of the gas baffle and the first flow guide surface.

A method for separating nitrogen from an inlet gas having less than 25 mole % nitrogen includes supplying the inlet gas having less than 25 mole % nitrogen to a nitrogen separation system configured with cryogenic refrigeration.

The present disclosure provides a gas liquefaction separator, a gas liquefaction recovery system, and a method for separating and recovering ethylene oxide. The gas liquefaction separator includes a housing, a blocking plate, a gas baffle, and a liquid collector, the latter three being located inside the housing. The liquid collector—an outer edge of which is connected to an inner wall of the housing—is located below the gas baffle, which is located below the blocking plate. The liquid collector includes a first flow guide surface, on a bottom portion of which is disposed a first hole. The gas baffle—an upper surface of which forms a second flow guide surface and an outer edge of which has a protrusion(s)—is connected to the first flow guide surface through the protrusion(s), thereby forming a second hole between the outer edge of the gas baffle and the first flow guide surface.

A device for distributing a fluid to a processing component includes a vessel having an inlet port for receiving a stream of fluid. A vapor outlet line is in fluid communication with the fluid processing component and has a vapor outlet line inlet in fluid communication with the headspace of the vessel. A liquid outlet line has a liquid outlet line inlet in fluid communication with a liquid side of the vessel and the fluid processing component. A bypass line has a bypass line inlet in fluid communication with the liquid side of the vessel and a bypass line outlet in fluid communication with the vapor outlet line and is configured so that liquid travels through the bypass line and into the vapor outlet line when a liquid level within the vessel reaches a predetermined level so that a headspace is maintained above the liquid level as liquid enters the vessel through the inlet port, and liquid does not travel from the bypass line into the vapor outlet line when a liquid level within the vessel is below the predetermined level.

Embodiments provide a method for preventing shutdowns in LNG facilities by removing heavy hydrocarbons from the inlet gas supply. According to an embodiment, there is provided an LNG facility treating pipeline quality natural gas that is contaminated with lubrication oil and low concentrations of heavy hydrocarbons. Due to contamination, the behavior of the pipeline quality natural gas is not properly predicted by thermodynamic modeling. In an embodiment, heavy hydrocarbons are removed by a drain system in a heat exchanger. In an embodiment, heavy hydrocarbons are removed by a treatment bed.

In a method for compressing a gas that is to be separated in a low-temperature CO.sub.2 separation unit using at least one partial condensation step and/or at least one distillation step, the gas that is to be separated has a variable composition and/or variable flow rate, the gas that is to be separated is compressed in a compressor to produce a compressed gas and the inlet pressure of the gas that is to be separated, entering the compressor, is modified according to the CO.sub.2 content and/or the flow rate of the gas that is to be separated so as to reduce the variations in volumetric flow rate of the gas that is to be separated entering the compressor.

A process for establishing vacuum insulation under cryogenic condition and an apparatus compatible with such process are described. When an insulation enclosure filled with high purity CO.sub.2 is evacuated to around 100 absolute Pa at ambient temperature, hard vacuum of below 1 absolute Pa may be automatically obtained within the insulation enclosure when temperature drops to around or below 170 C. This process can be employed to provide vacuum insulation for cold box housing air separation units operated under cryogenic condition.

A method for operating a natural gas liquids processing (NGL) system, the system being selectively configured in either an ethane rejection configuration or an ethane recovery configuration, the method comprising, when the NGL system is in the ethane rejection configuration, collecting a reboiler bottom stream that, in the ethane rejection configuration, includes ethane in an amount of less than 5% by volume, and when the NGL system is in the ethane recovery configuration, collecting a reboiler bottom stream that, in the ethane recovery configuration, includes ethane in an amount of at least about 30% by volume.