Abstract: An Apparatus for purifying a feed stream containing carbon dioxide in which the feed stream, after having been compressed and dried, is partly cooled and then used to reboil a stripping column. Thereafter, the feed stream is further cooled and expanded to a lower operational temperature of the stripping column. A carbon dioxide product stream composed of the liquid column bottoms of the stripping column is expanded at one or more pressures to generate refrigeration, then fully vaporized within the main heat exchanger and compressed by a compressor to produce a compressed carbon dioxide product. Refrigeration is recovered in the main heat exchanger from a column overhead stream extracted from the stripping column within the main heat exchanger either directly or indirectly by auxiliary processing in which carbon dioxide is further separated and optionally recycled back to the main compressor used in compressing the feed stream.

Abstract: A pressure differential of a feed gas (110) between a compressor (120) and expander (160) is employed to cool the feed gas to condense and remove at least a portion of one component to produce a partially depleted feed gas from which another component may then be removed. In especially preferred aspects, the feed gas comprises C2-C5 hydrocarbons and hydrogen, wherein the hydrocarbons are condensed in the cooler and hydrogen is removed using a pressure swing adsorption unit (180).

Abstract: A method to recover NGL's at gas Pressure Reducing Stations. A first step involve providing at least one heat exchanger having a flow path for passage of high pressure natural gas with a counter current depressurized lean cold gas. A second step involves passing the high pressure natural gas stream in a counter current flow with the lean cold gas and cooling it before de-pressurization. A third step involves the expansion of the high pressure cooled gas in a gas expander. The expansion of the gas generates shaft work which is converted into electrical power by the power generator and the expanded low pressure and cold gas enters a separator where NGL's are recovered. This process results in the recovery NGL's, electricity and the displacement of a slipstream of natural that is presently used to pre-heat gas at Pressure Reduction Stations.

Abstract: An LNG facility employing an enhanced nitrogen removal system that concentrates the amount of nitrogen in the feed stream to a nitrogen removal unit (NRU) to thereby increase the separation efficiency of the NRU. In one embodiment, the nitrogen removal system comprises a multistage separation vessel operable to separate nitrogen from a cooled natural gas stream. At least a portion of the resulting nitrogen-containing stream exiting the multistage separation vessel can be used as a refrigerant, processed to a nitrogen removal unit, and/or utilized as fuel gas for the LNG facility.

Abstract: Disclosed is a liquefied natural gas composition. The composition contains methane, ethane and propane and butane. The composition contains a substantial amount of butane while being substantially free of hydrocarbon molecules larger than butane.

Abstract: A process for producing aromatic hydrocarbons which comprises a) contacting ethane or mixed lower alkanes with an aromatic hydrocarbon conversion catalyst to produce reaction products including benzene, b) separating methane, hydrogen, and C2-5 hydrocarbons from the reaction products of step a), and c) hydrodealkylating the remaining reaction products to produce benzene. In a preferred embodiment, the feed is split into two streams, one of which is catalytically or thermally cracked to produce ethylene which is then combined with the remaining ethane or lower alkanes and contacted with the aromatic hydrocarbon conversion catalyst.

Abstract: A drive system for a refrigeration compressor such as is used in a natural gas liquefaction plant, allowing the desired compressor speed and maximum turbine efficiency to be maintained throughout varying ambient temperature conditions. A gas turbine is used with an electric starter motor with drive-through capability located on a common drive shaft between the turbine and the compressor. A variable frequency drive (VFD) is connected between the electrical power grid and the electric motor for smooth startups, but also to allow excess turbine mechanical power to be converted to electrical power by the motor operating as a generator, and delivered to the grid at the grid frequency. Pulse width modulation technology may be used to reduce harmonic distortion in the VFD's output. The starter motor also functions as a helper motor when the turbine output is insufficient to drive the compressor at the rotational speed needed to meet throughput requirements.

Abstract: A process for the recovery of ethane, ethylene, propane, propylene, and heavier hydrocarbon components from a hydrocarbon gas stream is disclosed. The stream is cooled and divided into first and second streams. The first stream is further cooled to condense substantially all of it and is thereafter expanded to the fractionation tower pressure and supplied to the fractionation tower at a first mid-column feed position. The second stream is expanded to the tower pressure and is then supplied to the column at a second mid-column feed position. A vapor distillation stream is withdrawn from the column above the feed point of the second stream and is then directed into heat exchange relation with the tower overhead vapor stream to cool the vapor distillation stream and condense at least a part of it, forming a condensed stream. At least a portion of the condensed stream is directed to the fractionation tower as its top feed.

Abstract: The present invention relates to a process and apparatus for producing crude helium, liquefied natural gas product, and synthesis gas from natural gas. A natural gas comprising helium and methane is cooled to produce cooled natural gas. At least a portion of the helium and methane from the cooled natural gas is separated into a vapor comprising helium, from which crude helium is derived, and a liquid comprising methane. At least a portion of the methane from this liquid is separated into a vapor, which is reacted to produce synthesis gas, and a liquid, from which liquefied natural gas is derived. Additional heat exchange and separation steps may be included.

Abstract: A gas condensate production plant comprises a plurality of separation units in which C2 and/or C3 lighter components are stripped from the separator feeds using compressed heated stripping vapor produced from the feed in respective downstream separation units. Contemplated plants substantially reduce heating and cooling duties by using the waste heat from the compressor discharges in the separation process. Furthermore, the multi-stage fractionation according to the inventive subject matter provides improved gas condensate recovery at reduced energy costs.

Abstract: Plant and method for liquefying natural gas. The plant comprises a common pre-cooling heat exchanger train (1), two natural gas liquids extraction units (100, 100?) and two main heat exchangers (200, 200?) to cool the overhead light fraction from its corresponding natural gas liquids extraction unit to liquefaction.

Abstract: The invention comprises a process of removing carbon dioxide from a natural gas feed stream comprising sending a natural gas feed stream comprising methane and carbon dioxide through an adsorbent bed to produce a carbon dioxide depleted methane rich product stream after removal of carbon dioxide. The adsorbent bed is regenerated and then the spent regeneration gas stream cooled to produce a cooled spent regeneration gas stream that is sent to a membrane element. A permeate stream passes through the membrane element and a residue stream passes by the membrane element without passing through said membrane element. Substantially all of the carbon dioxide and a minor portion of the methane comprises the permeate stream which is disposed of and a major portion of the methane and a minor portion of the carbon dioxide comprises the residue stream which is then recirculated to the regeneration gas stream.

Abstract: A relatively simple and energy efficient multiple stage cryogenic process for the purification of a hydrogen-rich stream by the removal of acid gases, mainly CO2 and H2S, by method of autorefrigeration and delivering or producing those acid gases, mainly CO2, at pressure sufficiently high for disposal by containment, commonly known as sequestration. Autorefrigeration is comprised of (a) condensing acid gases from the syngas stream by cooling the syngas, (b) separating the liquefied acid gases from the syngas, and (c) evaporating the liquefied acid gases at a pressure lower than that of the syngas to provide cooling. The process is composed of multiple autorefrigeration stages to generate multiple acid gas product streams with a pressure as high as practical in each stream so as to lessen the power needed to pressurize the acid gas streams for sequestration.

Abstract: This process includes the following steps: (a) the feed natural gas (101) is introduced into a first distillation column (31) which produces, as top product, a pretreated natural gas (111), which pretreated natural gas (111) no longer contains practically any C6+ hydrocarbons; (b) the pretreated natural gas (111) is introduced into an NGL recovery unit (19) comprising at least a second distillation column (49), so as to produce, on the one hand, as column top product, a purified natural gas (151) and, on the other hand, an NGL cut (15); and (c) the said liquefiable natural gas (161) is formed from the purified natural gas (151) resulting from step (b).

Abstract: The invention relates to a method for fractionating a gas produced by the pyrolysis of hydrocarbons (1) for the recovery of C2 and higher hydrocarbons, in particular ethylene and ethane, comprising an operation (70) for compressing and drying gas (1) as a result of it passing into a series of compressors (3, 10, 17, 24, 36), an operation (80) for progressively cooling and partially liquefying the gas produced by compression and drying operation (70) as a result of it successively passing into a cryogenic exchanger (62), and a distillation operation (90) in a column (64), and the corresponding installation. According to the invention, cryogenic exchanger (62) is cooled by at least one cooling liquid (400) which is liquid natural gas (LNG).

Abstract: The natural gas flowing in through line 1 is cooled, then expanded in turbine T1. The liquid at the bottom of drum D2 is the liquefied natural gas. The gas at the top of drum D2 is compressed by compressor K1, then fed into the treating plant using a Fischer-Tropsch process to convert the natural gas to natural gas liquid.

Abstract: A cryogenic process and apparatus to recover hydrogen from a fuel gas stream. The process can be stand alone or can be combined with existing processes, such as recovery of LPG from a fuel gas stream. In the stand-alone process, the fuel gas is cooled in one or more stages and sent to a cold separator that is used to separate the feed into a liquid and vapor stream. The liquid stream, is then warmed, compressed and then cooled and sent for further processing. The vapor stream, which contains hydrogen, is compressed, cooled when needed, and then returned for use in the existing facility or exported. The stand-alone process can be integrated within an LPG recovery process. The result of this cryogenic process is recovery of hydrogen from a fuel gas stream with only a slight decrease in hydrogen purity.

Abstract: The invention relates to a method for fractionating a gas produced by the pyrolysis of hydrocarbons (1) for the recovery of C2 and higher hydrocarbons, in particular ethylene and ethane, comprising an operation (70) for compressing and drying gas (1) as a result of it passing into a series of compressors (3, 10, 17, 24, 36), an operation (80) for progressively cooling and partially liquefying the gas produced by compression and drying operation (70) as a result of it successively passing into a cryogenic exchanger (62), and a distillation operation (90) in a column (64), and the corresponding installation.

Abstract: An ethane recovery process utilizing multiple reflux streams is provided. Feed gas is cooled, partially condensed, and separated into a first liquid stream and a first vapor stream. First liquid stream is expanded and sent to a demethanizer. First vapor stream is split into a first and a second separator vapor streams. First separator vapor stream is expanded and sent to demethanizer. Second separator vapor stream is partially condensed and is separated into a reflux separator liquid stream, which is sent to demethanizer, and a reflux separator vapor stream, which is condensed and sent to demethanizer. Demethanizer produces a tower bottom stream containing a substantial amount ethane and heavier components, and a tower overhead stream containing a substantial amount remaining lighter components and forms a residue gas stream. A portion of residue gas stream is cooled, condensed, and sent to the demethanizer tower as top reflux stream.

Abstract: A method of separating volatile organic components, so-called VOC, from crude oil, where, as it is loaded onto a ship, the crude oil is passed into a process vessel (2) in which is established a negative pressure adjusted according to the vapour pressure of the oil, from where the liquid phase of the crude oil flows to the ship's cargo tanks, while the gas phase, the VOC, is extracted from the process vessel (2).

Abstract: An integrated process for producing LNG and GTL products is provided comprising cooling natural gas in at least one cooling step so as to provide a cooled natural gas stream; processing the cooled natural gas stream in at least two expansion/separation cycles, each expansion/separation cycle comprising the Substeps of (a) isentropically or isenthalpically expanding at least a portion of the cooled natural gas steam for producing a natural gas vapor component and a LNG component, (b) separating at least a portion of the natural gas vapor component from the LNG component, and (c) repeating substeps (a) through (b) wherein at least a portion of the LNG component from the previous expansion/separation cycle is directed to each successive Substep (a) and wherein the final LNG product is the LNG component after the final separating step and is substantially liquid at substantially atmospheric pressure; and converting at least a portion of one or more of the expansion/separation cycle natural gas vapor components in

Abstract: A process for pretreating a very acid natural gas containing a substantial amount of hydrogen sulfide (H2S), possibly combined with carbon dioxide (CO2), includes at least a stage wherein the initial natural gas is contacted in a distillation column with a liquid condensate itself resulting from cooling of the gaseous fraction obtained during the contacting stage. This solution allows to eventually recover at a lower cost a gas enriched in methane, depleted in hydrogen sulfide and freed from substantially all of the water it contains, and a liquid phase containing most of the hydrogen sulfide, substantially all of the water and depleted in hydrocarbon. Control of the thermodynamic conditions during the stages that characterize the process, according to the water content of the gas during treatment, allows progressive exhaustion of the water contained in the gas while preventing hydrates formation.

Abstract: An improved process for recovery of liquefied petroleum gas from a raw natural gas feed stream, capable of achieving ultra high propane recovery yields, thereby separating substantially all of the propane and heavier hydrocarbon components from a predominantly methane and ethane feed gas stream. The process includes steps to liquefy all of the propane and heavier components and part of the methane and ethane components by cooling, condensing, and absorption. The residual feed gas containing the methane and ethane components, being the final gaseous product stream. The liquefied portion of the feed is separated and then fractionated in a distilling unit to produce a propane and heavier product stream. The distilling unit overhead vapors are cooled and condensed in two steps to provide reflux for the top of the deethanizer and for the feed gas absorption.

Abstract: An apparatus for compressing gaseous refrigerant for use in a refrigeration circuit of a liquefaction plant, which refrigeration circuit has an inlet, a first outlet for refrigerant at low pressure, a second outlet for refrigerant at intermediate pressure, a third outlet for refrigerant at high pressure and a fourth outlet for refrigerant at high-pressure, which apparatus comprises a first and a second compressor, wherein the first compressor has a main inlet connected to the first outlet, a side-inlet connected to the third outlet and an outlet connected to the inlet of the refrigeration circuit, and wherein the second compressor has a main inlet connected to the second outlet, a side-inlet connected to the fourth outlet and an outlet connected to the inlet of the refrigeration circuit.

Abstract: An apparatus and method for producing liquefied natural gas. A liquefaction plant may be coupled to a source of unpurified natural gas, such as a natural gas pipeline at a pressure letdown station. A portion of the gas is drawn off and split into a process stream and a cooling stream. The cooling stream passes through a turbo expander creating work output. A compressor is driven by the work output and compresses the process stream. The compressed process stream is cooled, such as by the expanded cooling stream. The cooled, compressed process stream is divided into first and second portions with the first portion being expanded to liquefy the natural gas. A gas-liquid separator separates the vapor from the liquid natural gas. The second portion of the cooled, compressed process stream is also expanded and used to cool the compressed process stream. Additional features and techniques may be integrated with the liquefaction process including a water clean-up cycle and a carbon dioxide (CO2) clean-up cycle.

Abstract: The present invention is directed to a process for producing LNG by directing a feed stream comprising natural gas to a cooling stage that (a) cools the feed stream in at least one cooling step producing a cooled feed stream, (b) expands the cooled feed stream in at least one expansion step by reducing the pressure of the cooled feed stream producing a refrigerated vapor component and a liquid component, and (c) separates at least a portion of the refrigerated vapor component from the liquid component wherein at least a portion of the cooling for the process is derived from at least a portion of the refrigerated vapor component; and repeating steps (a) through (c) one or more times until at least substantial portion of the feed stream in the first cooling stage is processed into LNG wherein the feed stream in step (a) comprises at least a portion of the liquid component produced from a previous cooling stage.

Abstract: Systems and methods are provided for delivering pressurized liquefied natural gas to an import terminal equipped with containers and vaporization facilities suitable for conventional LNG.

Abstract: Apparatus for recovering vapor during de-pressuring of a vessel, and for those facilities with such a need, for recovering vapor during the liquid filling, or liquid removing, from a vessel. In de-pressuring mode, the vapor and inert gas purging the vessel are processed to recover multiple product vapors with vapor pressures from as low as 0.1 PSIG to about 100 PSIG. Higher values up to 250 PSIG are also processed economically by an optional third-stage, stand-alone system. This system produces overall product recovery rates over 99% and inert gas recovery over 99% at the latter part of the cycle as recycle gas.

Abstract: An apparatus for use on board ship to reliquefy a compressed vapour employs pre-assemblies of components. The reliquefaction is effected in a closed cycle in which a working fluid is compressed in at least one compressor, is cooled in a first heat exchanger, is expanded in a turbine and is warmed in a second heat exchanger in which the compressed vapour is at least partially condensed. The apparatus comprises a first pre-assembly including the second heat exchanger and a second pre-assembly including the first heat exchanger, the compressor and the expansion turbine are positioned. The pre-assemblies are positioned on respective platforms.

Abstract: A process for liquefaction of and nitrogen extraction from natural gas, an installation for implementation of the process, and gases obtained by this process. In the process, a first top fraction is cooled and liquefied, separated into a second top fraction which is relatively volatile and which provides gaseous nitrogen, and into a second bottom fraction which is withdrawn. The first bottom fraction is cooled in order to provide liquefied natural gas essentially free nitrogen.

Abstract: A process for partial liquefaction of a fluid G at least partially formed from hydrocarbons simultaneously produces: a fraction that is liquid after expansion; a gas fraction representing at least 10% by weight, which can either be re-injected or used to produce electricity; and comprises at least two refrigeration steps during which: in the first step a), the essentially gaseous fluid G is cooled using an external refrigerant M such that at the end of said first step, it is at least partially liquid at the operating pressure; and in the second step b), liquefaction of said fluid G is completed if necessary and said fluid G is sub-cooled, using a portion of the same fluid G, said portion being thus expanded and vaporised to produce the cooling necessary to recover the other portion of said fluid G that is completely liquid at the storage pressure.

Abstract: A method for generating refrigeration using a turboexpander or reverse Brayton cycle which can more efficiently generate refrigeration especially to cryogenic temperatures using a defined refrigerant mixture containing argon and/or nitrogen.

Abstract: A cryogenic refrigeration system wherein refrigeration is provided to a heat load by a warming multicomponent refrigerant fluid recirculating in a refrigeration circuit and by cryogenic liquid separately provided to the heat load in direct or indirect heat exchange with the heat load.

Abstract: A process for the separation and liquefaction of component gasses from a pressurized mix gas stream is disclosed. The process involves cooling the pressurized mixed gas stream in a heat exchanger so as to condensing one or more of the gas components having the highest condensation point; separating the condensed components from the remaining mixed gas stream in a gas-liquid separator; cooling the separated condensed component stream by passing it through an expander; and passing the cooled component stream back through the heat exchanger such that the cooled component stream functions as the refrigerant for the heat exchanger. The cycle is then repeated for the remaining mixed gas stream so as to draw off the next component gas and further cool the remaining mixed gas stream. The process continues until all of the component gases are separated from the desired gas stream. The final gas stream is then passed through a final heat exchanger and expander.

Abstract: The invention relates to a process of manufacturing a pressurized multi-component liquid from a pressurized, multi-component stream, such as natural gas, which contains C5+ components and at least one component of C1, C2, C3, or C4. The process selectively removes from the multi-component stream one or more of the C5+ components that would be expected to crystallize at the selected temperature and pressure of the pressurized multi-component liquid product and leaves in the multi-component stream at least one C5+ component. The multi-component stream is then liquefied to produce a pressurized liquid substantially free of crystallized C5+ components. The removal of the C5+ components can be by selective fractionation or crystallization.

Abstract: A method and apparatus for providing direct contact refrigeration to a heat source wherein refrigeration is generated using a recirculating defined multicomponent refrigerant fluid, and transferred to a direct contact refrigerant fluid which directly contacts the heat source.

Abstract: A process for producing a liquified natural gas stream that includes cooling at least a portion of a pressurized natural gas feed stream by heat exchange contact with first and second expanded refrigerants that are used in independent refrigeration cycles. The first expanded refrigerant is selected from methane, ethane and treated and pressurized natural gas. The second expanded refrigerant is nitrogen.

Abstract: Plant for liquefying natural gas comprising one pre-cooling heat exchanger (2) having an inlet (13) for natural gas and an outlet (14) for cooled natural gas, a pre-cooling refrigerant circuit (3), one distributor (4) having an inlet (18) connected to the outlet (14) for cooled natural gas and having two outlets (22, 23), two main heat exchangers (5, 5′), and two main refrigerant circuits (9, 9′) each co-operating with one liquefaction heat exchanger (5, 5′).

Abstract: This invention relates to process for liquefying a pressurized gas stream rich in methane. In a first step of the process, a first fraction of a pressurized feed stream, preferably at a pressure above 11,000 kPa, is withdrawn and entropically expanded to a lower pressure to cool and at least partially liquefy the withdrawn first fraction. A second fraction of the feed stream is cooled by indirect heat exchange with the expanded first fraction. The second fraction is subsequently expanded to a lower pressure, thereby at least partially liquefying the second fraction of the pressurized gas stream. The liquefied second fraction is withdrawn from the process as a pressurized product stream having a temperature above −112° C. and a pressure at or above its bubble point pressure.

Abstract: Liquefying a stream enriched in methane comprising a) supplying a natural gas stream to scrub column, removing in the scrub column heavier hydrocarbons from the natural gas stream to obtain a gaseous overhead stream withdrawn from the top of the scrub column, partly condensing the gaseous overhead stream and removing from it a condensate stream, which is returned to the upper part of the scrub column as reflux; b) liquefying the stream enriched in methane in a tube arranged in a main heat exchanger by indirect heat exchange with a multicomponent refrigerant evaporating at low refrigerant withdrawn from the shell side of the main heat exchanger and partly condensing it at an elevated refrigerant pressure, and c) compressing the multicomponent refrigerant pressure in a tube arranged in an auxiliary heat exchanger by indirect heat exchange with an auxiliary multicomponent refrigerant evaporating at low auxiliary refrigerant pressure to obtain multicomponent refrigerant for use in step b), wherein partly condensi

Abstract: A process for enhancing recovery of ethylene, ethane and heavier components using a cryogenic distillation column which involves dividing the feed gas into a first gaseous stream and a main gaseous stream. The first gaseous stream is compressed and cooled, and then expanded and introduced into the cryogenic distillation column as main reflux stream, or is further processed to generate at least one reflux stream to the cryogenic distillation column.

Abstract: A method of gas liquefaction wherein the refrigeration to cool and liquefy an essentially water-free feed gas is provided by a single recirculating mixed refrigerant cycle in which refrigeration is provided by the vaporization of two mixed refrigerant streams of different compositions at a lower and higher pressure levels respectively. A lower pressure level vaporizing refrigerant cools the feed gas stream in a first cooling zone and a higher pressure level vaporizing refrigerant further cools and condenses the cooled gas in a second cooling zone to provide the final liquid product. The lower pressure level vaporizing refrigerant is provided by one or more liquids obtained by ambient cooling of compressed mixed refrigerant vapor.

Abstract: Method of producing liquefied natural gas (LNG) whereby refrigeration for cooling and liquefaction is provided by a mixed refrigerant system precooled by another refrigeration system. At least one liquid stream is derived from the partial condensation and separation of the mixed refrigerant at a temperature higher than the lowest temperature provided by the precooling system when the mixed refrigerant is condensed at a final highest pressure. When the mixed refrigerant is condensed at a pressure lower than the final highest pressure, condensation is effected at a temperatures equal or higher than the lowest temperature provided by the precooling system. The mixed refrigerant liquid is used to provide refrigeration at a temperature lower than that provided by the precooling system.

Abstract: The olefin-hydrogen effluent vapor stream from a dehydrogenation process is separated by a cryogenic separation method utilizing a cryogenic separation system. The method does not require external refrigeration and reheats and portions an expander feed stream to extract energy and controls the warm end and cold end temperature differences in the primary heat exchanger to provide energy savings and economical operation and material use.

Abstract: An improved process for separating a hydrocarbon bearing feed gas containing methane and lighter, C2 (ethylene and/or ethane), C3 (propylene and/or propane) and heavier components into a fraction containing predominantly C2 and lighter components and a fraction containing predominantly C3 and heavier hydrocarbon components including the steps of cooling and partially condensing and delivering the feed stream to a separator to provide a first residue vapor and a C3 containing liquid, directing a portion of the C3 containing liquid into a heavy-ends fractionation column wherein the liquid is separated into a second hydrocarbon bearing vapor residue, a second C2 containing liquid stream, and a C3 containing product.

Abstract: Carbon Dioxide is separated from other gases using autorefrigeration. In general, a feed gas containing Carbon Dioxide is compressed (100), and then expanded (250) to produce work. Carbon Dioxide in the feed gas is liquefied, and the liquefied Carbon Dioxide is then separated (282) from other components that remain gaseous. While all commercially viable embodiments are contemplated, embodiments are preferred in which the claimed methods and apparatus provide significant commercial advantages over the prior art. For example, it is preferred that feed gases are employed in which the Carbon Dioxide concentration is at least 40%, more preferably at least 60%, and still more preferably at least 80%. All percentages herein are given in mole percent. It is also preferred that feed gases be compressed to at least 15 bar absolute in all applications, at least 30 bar absolute in some embodiments, and at least 60 bar absolute in other embodiments.

Abstract: A process for gas liquefaction, particularly nitrogen liquefaction, which combines the use of a nitrogen autorefrigeration cooling cycle with one or more closed-loop refrigeration cycles using two or more refrigerant components. The closed-loop refrigeration cycle or cycles provide refrigeration in a temperature range having a lowest temperature between about −125° F. and about −250° F. A nitrogen expander cycle provides additional refrigeration, a portion of which is provided at temperatures below the lowest temperature of the closed-loop or recirculating refrigeration cycle or cycles. The lowest temperature of the nitrogen expander cycle refrigeration range is between about −220° F. and about −320° F. The combined use of the two different refrigerant systems allows each system to operate most efficiently in the optimum temperature range, thereby reducing the power consumption required for liquefaction.

Abstract: A refrigeration method using a non-aqueous, non-hydrocarbon refrigerant to contact a hydrocarbon composition comprising a hydrocarbon vapor phase and a hydrocarbon liquid phase in order to lower the temperature of the hydrocarbon composition by lowering the partial pressure of the hydrocarbon vapor phase.

Abstract: The present invention relates to a process of liquefying a gaseous, methane-rich feed to obtain a liquefied product by supplying the gaseous, methane-rich feed at elevated pressure to a first tube side of a main heat exchanger at its warm end, cooling, liquefying and sub-cooling the gaseous, methane-rich feed against evaporating refrigerant to get a liquefied stream, removing the liquefied stream from the main heat exchanger at its cold end and passing the liquefied stream to storage as liquefied product, removing evaporated refrigerant from the shell side of the main heat exchanger at its warm end, compressing in at least one refrigerant compressor the evaporated refrigerant to get high-pressure refrigerant, partly condensing the high-pressure refrigerant and separating the partly-condensed refrigerant into a liquid heavy refrigerant fraction and a gaseous light refrigerant fraction, sub-cooling the heavy refrigerant fraction in a second tube side of the main heat exchanger to get a sub-cooled heavy refriger

Abstract: A process is disclosed to remove at least one high volatility component, such as nitrogen, from a pressurized natural gas to produce pressurized liquefied natural gas that is lean in nitrogen and has a temperature above about −112° C. (−170° F.). A pressurized feed natural gas containing nitrogen is expanded and passed to a fractionation column. The fractionation column produces a first vapor stream that has enhanced nitrogen content and a first liquid stream. The vapor stream is cooled to produce a vapor phase and a liquid phase. The vapor and liquid phases are then phase separated to produce a second vapor stream and a second liquid stream. The second liquid stream is returned to the fractionation column as reflux. The second vapor stream is preferably used to cool the incoming feed stream. The first liquid stream is removed from the fractionation system as a product stream lean in nitrogen.