A method of designing, constructing, and operating a hydrocarbon gas treatment plant is disclosed. A target hydrocarbon production range for a hydrocarbon gas meeting a required product specification is established. A cryogenic distillation column is designed and constructed with a vapor capacity to meet the target hydrocarbon production range. A variable feed refrigeration system is incorporated to cool an inlet feed of the hydrocarbon gas. The variable feed refrigeration system is designed to handle the target hydrocarbon production range and a wide range of contaminant concentrations in the inlet feed. A variable bottoms heating system is incorporated to handle heating duties associated with the wide range of contaminant concentrations in the inlet feed. A variable bottoms pumping system is incorporated to handle liquid flows associated with the wide range of contaminant concentrations in the inlet feed.

A refrigerant circuit includes a first compression stage for compressing a mixed refrigerant gas, the first compression stage including at least a first compressor body and a second parallel compressor body, each compressor body including a suction inlet and an outlet, a first distribution means for splitting the flow of refrigerant gas to the first stage of compression across the at least two parallel compressor bodies, such that a first stream of refrigerant gas is fed to the suction inlet of the first compressor body and a second stream of refrigerant gas is fed to the suction inlet of the second compressor body, a second compression stage for compressing the mixed refrigerant gas, and a first merging means for recombining the first stream of refrigerant gas with the second stream of refrigerant gas downstream of the first compression stage for delivery to the second compression stage.

A method for producing hydrocarbons is proposed, in which a product stream containing hydrocarbons is produced from a methane-rich feed stream and from an oxygen-rich feed stream in a reaction unit which is configured for implementing a method for oxidative coupling of methane, the product stream or at least a stream formed therefrom being treated cryogenically in at least one separation unit using at least one liquid, methane-rich stream. It is provided that in the at least one separation unit (10) a recycle stream is formed from methane contained in product stream (c) and from methane contained in the at least one liquid, methane-rich stream (e, v), the recycle stream being fed to the reaction unit (1) as the methane-rich feed stream (a), and in that the liquid, methane-rich stream (e, v) is provided as makeup.

The invention relates to a method for controlling a temperature distribution in a heat exchanger, in which an actual temperature distribution in the heat exchanger is measured by means of at least one optical waveguide arranged in the heat exchanger, in particular in the form of a glass fiber, light being launched into the optical waveguide and light that is scattered in the optical waveguide being evaluated for determining the actual temperature distribution, and at least one flow of a fluid medium that is carried in the heat exchanger being controlled in such a way that the actual temperature distribution is made to approximate a pre-defined target temperature distribution. The invention also relates to a device for carrying out a method for controlling a temperature distribution in a heat exchanger.

A method for operating an air separation unit during an unexpected disturbance is provided. The method can include the steps of: determining that a process disturbance has occurred; starting-up a liquid back-up system that is configured to deliver a product gas at a desired product pressure; and introducing compressed air from an air accumulator into the air separation unit at a location that is downstream a main air compressor and upstream a cold box, wherein the compressed air is introduced in an amount that is effective for maintaining nominal operation of the air separation unit during the process disturbance and until the liquid back-up system is delivering the product gas at the desired product pressure.

A method and apparatus for producing liquefied natural gas. A portion of a natural gas stream is cooled in a first heat exchanger and re-combined with the natural gas stream, and heavy hydrocarbons are removed therefrom to generate a separated natural gas stream and a separator bottom stream. Liquids are separated from the separator bottom stream to form an overhead stream, which is cooled and separated to form a recycle gas stream. The recycle gas stream is compressed. A first portion of the compressed recycle gas stream is directed through the first heat exchanger and directed to the separator as a column reflux stream. The separated to natural gas stream is used as a coolant in the first heat exchanger to thereby generate a pretreated natural gas stream, which is compressed and liquefied.

A method and apparatus for producing liquefied natural gas. A portion of a natural gas stream is cooled in a heat exchanger and combined with the natural gas stream. Heavy hydrocarbons are removed from the combined natural gas stream, and the resulting separated natural gas stream is partially condensed in the first heat exchanger, with a liquid stream separated therefrom. The natural gas stream is warmed in the first heat exchanger and then is compressed and cooled. The resultant cooled compressed natural gas stream is expanded, thereby forming a chilled natural gas stream that is separated into a refrigerant stream and a non-refrigerant stream. The refrigerant stream recycled to the heat exchanger to be warmed through heat exchange with one or more process streams associated with pretreating the natural gas stream, thereby generating a warmed refrigerant stream. The warmed refrigerant stream and the non-refrigerant stream are liquefied.

An atmospheric water harvesting system includes a water-harvesting unit with an air mover and a heat exchanger. The water-harvesting unit may also include one or more screens on which water can condense. The water-harvesting unit is supplied by a coolant pathway, in which a non-cryogenic fluid coolant flows. A cryogenic cell is in the coolant pathway. The cryogenic cell receives the fluid coolant and removes heat from it by causing or allowing a controlled heat transfer between the fluid coolant and a first cryogen sealed within an inner vessel in the cryogenic cell. The coolant may be a liquid at operating temperatures, and the cryogenic cell may cool it to an appropriate temperature without a phase change, essentially acting as a “cold battery” to remove heat from the coolant.

A method for liquefying a hydrocarbon stream using at least one heat exchanger of the plate and fin type having at least one first part and one second part, the first and second parts being physically separate and each comprising at least one stack of a plurality of plates that are parallel to one another and to a longitudinal direction that is substantially vertical, the plates of the first part and the plates of the second part being stacked in a stacking direction that is orthogonal to the plates, the plates being stacked with spacing so as to define between them a plurality of first passages for the flow of at least part of a second two-phase cooling stream in the first part and a plurality of second passages for the flow of at least part of a first two-phase cooling stream in the second part.

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.