Abstract: For liquefying a hydrocarbon-rich fraction, in particular natural gas, the hydrocarbon-rich fraction which is to be liquefied is merely cooled and liquefied against a coolant mixture, and the coolant mixture, before its cooling, is separated into a gas phase and a liquid phase, and wherein the gas (5) and the liquid phases (6) are cooled (E) separately and not until after cooling (E) has been performed are they expanded (a, b) and recombined (8).

Abstract: A method of liquefying natural gas from a feed stream (10) comprising at least the steps of: passing the feed stream (10) against a mixed refrigerant being cycled through a heat exchanger (12), to provide an at least partly liquefied hydrocarbon stream (20) having a temperature below ?100° C.; outflowing the mixed refrigerant as a liquid and vapour outflow refrigerant stream (80) and passing it through a first separator (18) to provide a vapour refrigerant stream (90) and a liquid refrigerant stream (110); recycling without substantial heat exchange the liquid refrigerant stream (110) into the heat exchanger (12); compressing and cooling the vapour refrigerant stream (90) to provide a cooled compressed stream (100) having a temperature below 0° C. and recycling it into the heat exchanger (12).

Abstract: A method for liquefying a hydrocarbon-rich stream is disclosed. In an embodiment, the hydrocarbon-rich stream is liquefied in a heat exchanger countercurrent to a three component refrigerant mixture. The refrigerant mixture is compressed in a two stage compressor. The refrigerant mixture is separated into a higher boiling fraction and a lower boiling fraction. A fluid fraction is recovered from a partial stream of the lower boiling fraction. The fluid fraction is supercooled and expanded to a pressure of the higher boiling fraction and the fluid fraction is provided to a compressor stage to which the higher boiling fraction is taken.

Abstract: A method and apparatus for compressing a natural gas stream is disclosed. The natural gas stream to be compressed is liquefied and then compressed by means of at least one cryogenic pump. Liquefaction of the natural gas stream to be compressed preferably takes place using the energy from a low-temperature process, specifically in the exchange of heat countercurrent to at least one medium to be heated, preferably countercurrent to a cryogenic medium.

Abstract: A design for equipment and process for reliquefaction of LNG boiloff gas, primarily for shipboard installation, has high thermodynamic efficiency and lower capital cost, smaller size (volume, footprint), lower weight, and less need for maintenance than systems utilizing the prior art. The main refrigerant gas compressor is reduced to a single stage turbocompressor. Optional elements include: compression of boiloff gas at ambient temperature; compression of boiloff gas in one or two stages; turboexpansion of refrigerant gas incorporating one or two turboexpanders; turboexpander energy recovery by mechanical loading, compressor drive, or electric generator; refrigerant sidestream for cooling at the lowest temperatures.

Abstract: A design for equipment and process for reliquefaction of LNG boiloff gas, primarily for shipboard installation, has high thermodynamic efficiency and lower capital cost, smaller size (volume, footprint), lower weight, and less need for maintenance than systems utilizing the prior art. The main refrigerant gas compressor is reduced to a single stage turbocompressor. Optional elements include: compression of boiloff gas at ambient temperature; compression of boiloff gas in one or two stages; turboexpansion of refrigerant gas incorporating one or two turboexpanders; turboexpander energy recovery by mechanical loading, compressor drive, or electric generator; refrigerant sidestream for cooling at the lowest temperatures.

Abstract: A method and apparatus of pre-heating LNG boil-off gas stream flowing from a reservoir in a reliquefaction system, before compression. The method comprises heat exchanging the BOG stream in a first heat exchanger, against a second coolant stream having a higher temperature than the BOG stream, where the second coolant stream is obtained by selectively splitting a first coolant stream into second and third coolant streams, third coolant stream being flowed into a first coolant passage in a reliquefaction system cold box, whereby the BOG has reached near-ambient temperatures prior to compression and the low temperature duty from the BOG is substantially preserved within the reliquefaction system, and thermal stresses in the cold box are reduced. Before the compression step, the BOG is pre-heated to substantially ambient temperatures, by heat exchanging the BOG with said coolant, said coolant prior to the heat exchange having a higher temperature than the BOG.

Abstract: A process and system is provided for removing total heat from a base load LNG liquefaction facility by using a hybrid cooling process. After liquefying a gas such as natural gas with a refrigerant, the refrigerant is transferred to a compression unit. In order to condense the compressed refrigerant, the refrigerant first flows through process coil bundles. As the refrigerant flows through the process coil bundles, water is sprayed, via a spray distribution system and a water reservoir, onto the outer surface of the process coil bundles. Air is passed over the process coil bundles via a fan system to allow heat transfer to take place and to cool and condense the refrigerant.

Abstract: A heat exchanger and associated methods for sublimating solid particles therein, for conveying fluids therethrough, or both. The heat exchanger includes a chamber, and a porous member having a porous wall having pores in communication with the chamber and an interior of the porous member. A first fluid is conveyed into the porous member while a second fluid is conveyed into the porous member through the porous wall. The second fluid may form a positive flow boundary layer along the porous wall to reduce or eliminate substantial contact between the first fluid and the interior of the porous wall. The combined first and second fluids are conveyed out of the porous member. Additionally, the first fluid and the second fluid may each be conveyed into the porous member at different temperatures and may exit the porous member at substantially the same temperature.

Abstract: The present invention provides for a process for providing cooling and controlling the refrigeration in a cooling loop used in the production of liquefied natural gas. A cooling loop in contact with a heat exchanger contains a refrigerant composition and by controlling the amount of a component in the refrigerant composition, the necessary level of cooling provided to the heat exchanger can be maintained.

Abstract: The assembly includes a boil-off gas line that carries storage tank boil-off gas to a condenser that uses condensing liquid from the liquid send-out line to condense the gas. A level control valve on the condensing liquid line actively controls the flow of condensing liquid based on the liquid level in the condenser. A check valve prevents liquid from the send-out line from flowing into the condenser through the condensate line that discharges condensate from the condenser to the send-out line.

Abstract: A boil off gas (“BOG”) condenser for use in LNG handling facilities which provides compensation for transient pressure changes in BOG flow due to variations in operations.

Abstract: A method for liquefying a hydrocarbon-rich stream, in particular a natural gas stream, is disclosed. A liquefaction of the hydrocarbon-rich stream takes place countercurrent to a refrigerant mixture cycle cascade consisting of two or three refrigerant mixture cycles. No additional process steps are involved in the heat exchange between the hydrocarbon-rich stream which is to be precooled and the refrigerant mixture of the first refrigerant mixture cycle.

Abstract: A process for the recovery of natural gas liquids (NGL) from liquefied natural gas (LNG) is disclosed. The LNG feed stream is subjected to a two stage separation process where the bottoms from the first stage separation containing C2+ hydrocarbons is split into two portions, with one portion being heated and used as a reflux during the second stage separation to recover the NGL product.

Abstract: A method of cold recovery in a cold compressed natural gas cycle, the method comprising: compressing air; drying air; heat exchanging air with cold compressed natural gas from a storage vessel, in a first heat exchanger, thereby forming cooled air; heat exchanging the cooled air with liquid methane, in a second heat exchanger, such that the cooled air becomes liquid air and the liquid methane becomes methane; heat exchanging the liquid air with natural gas from a pipeline, in a third heat exchanger, such that the natural gas cools to a cold compressed natural gas and the liquid air becomes air in a gaseous state; discharging the air in a gaseous state.

Abstract: Contemplated plants integrate regeneration of a freeze point depressant with LNG regasification and a power cycle. Most preferably, the plant is a combined cycle plant in which heat for reboiling the regenerator is provided by the steam cycle, and in which LNG refrigeration content is used to condense steam from the regenerator and to further subcool intake air for a combustion turbine.

Abstract: An LNG plant is configured to receive rich LNG and to produce LPG, lean LNG, and power using at least one fractionation column, wherein the fractionation portion of the plant can be optionally thermally coupled to a power cycle utilizing residual refrigeration from the processed lean LNG. Most preferably, a liquid portion of the rich LNG is pumped to pressure and heated, and the pressurized and superheated portion is expanded to produce electric energy before being fed into the column. The column overhead vapor is partially condensed, providing column reflux for high NGL recoveries, and the residual vapor is further condensed using refrigeration content of the rich LNG forming the lean LNG product, that is further pumped to pipeline pressure and subsequently vaporized using heated working fluid of the power cycle.

Abstract: The present invention relates to a method for the liquefaction of a hydrocarbon-rich stream, preferably a natural gas containing stream, by heat exchanging against a refrigerant (1a-d). The liquid refrigerant (19) is evaporated using heat from the hydrocarbon-rich stream, thereby obtaining an evaporated refrigerant (3a-d). The evaporated refrigerant (3a-d) is subsequently compressed (5), cooled (10) against ambient thereby fully condensing the compressed refrigerant. Next, the fully condensed compressed refrigerant (12) is further sub-cooled (14) by indirect heat exchange against an auxiliary refrigerant being cycled in an auxiliary refrigerant. Then the subcooled refrigerant (16) is expanded (18) thereby forming the liquid refrigerant (19).

Abstract: An improved apparatus and method for providing reflux to a refluxed heavies removal column of a LNG facility. The apparatus comprises stacked vertical core-in-kettle heat exchangers and an economizer disposed between the heat exchangers. The reflux stream originates from the methane-rich refrigerant of the methane refrigeration cycle. The liquid reflux stream generated by cooling the methane-rich stream in the vertical heat exchangers via indirect heat exchange with an upstream refrigerant.

Abstract: Disclosed are methods and systems for vaporization of liquefied natural gas (LNG) that employ a condensing gas stream to adjust the gross heating value (GHV) of the LNG such that, upon vaporization, a natural gas product is obtained that meets pipeline or other commercial specifications. The condensing gas can be air, nitrogen, or in embodiments, NGLs such as ethane, propane, or butane, or other combustible hydrocarbon such as dimethyl ether (DME) depending on a desired change in GHV. In some embodiments, the methods and systems employ an integrated air separation plant for generation of nitrogen used as a condensing gas, wherein a cool stream of a heat transfer medium, such as water, ethylene glycol, other common heat transfer fluids, or mixtures thereof, obtained by heat transfer during vaporization of the LNG is used to pre-cool an air feed to the air separation plant, or to cool other process streams associated therewith.

Abstract: A process for condensing a C3-C4 hydrocarbon vapor which comprises contacting the C3-C4 hydrocarbon vapor with a heat exchanger surface which is cooled by contact with LNG and recovering a liquefied C3-C4 product therefrom.

Abstract: An apparatus for and process for recovering LNG from reservoir natural gas which includes circulating a portion of the natural gas thru a gas cooling loop that includes heat exchanges, an expansion zone and compression zone. The process also includes removing liquids from the gas cooling loop, distilling those liquids to recover a distilled gas. The process also includes compressing and expanding various portions of the distilled gas and passing those portions thru heat exchangers shared with the gas cooling loop to effect heating/cooling as desired. The process also includes removing a portion of the LNG cooling loop as LNG product.

Abstract: In an integrated process and apparatus for the separation of air by cryogenic distillation and liquefaction of natural gas in which at least part of the refrigeration required to liquefy the natural gas is derived from at least one cryogenic air distillation plant comprising a main heat exchanger (7) and distillation columns (15, 17), wherein the natural gas (25) liquefies by indirect heat exchange in a heat exchanger (7, 32, 34) with a cold fluid (21, 26), the cold fluid being sent to the heat exchanger at least partially in liquid form and undergoing at least a partial vaporisation in the heat exchanger.

Abstract: A system and process for liquefying or storing gases at low temperatures using a cold recovery system. The system and process includes a cold recovery system having at least one cold recovery vessel configured to receive a gas stream and cool the gas stream by passing the gas stream through a cold recovery vessel. The cold recovery vessels includes a cold recovery material configured to cool the cooled gas stream, wherein the gas stream is fed through the cold recovery vessel through a pipe immersed in the cold recovery material to produce a liquefied or low temperature gas. The liquefied or low temperature gas is stored in a liquid or low temperature state in a storage tank. When the liquefied or low temperature gas is released from the storage tank, the gas vaporizes or expands through the pipe and cools the cold recovery material.

Abstract: An apparatus for controlling the pressure in a cargo tank 1 supplies BOG generated from liquefied natural gas stored in the cargo tank 1 to a burning system 6 through a compressor. In this apparatus, a reliquefaction plant 5 is disposed on the downstream side of first and second compressors 3 and 4 and on the upstream side of the cargo tank 1 so that BOG discharged from the second compressor 4 is liquefied by the reliquefaction plant 5 and the liquefied fluid is returned again into the cargo tank 1.

Abstract: The invention concerns a method for refrigerating liquefied natural gas under pressure (1), comprising a first step wherein the LNG (1) is cooled, expanded and separated (a) in a first base fraction (4) which is collected, and (b) a first top fraction (3) which is heated, compressed in a compressor (K1) and cooled into a first compressed fraction (5) which is collected; a second compressed fraction (6) is drawn from the fuel gas (5), cooled then mixed with the cooled and expanded LNG (1). The invention is characterised in that it comprises a second step wherein the second compressed fraction (6) is compressed and cooled, and a flux is (8) drawn and cooled, expanded and introduced in the compressor (K1). The invention also describes other embodiments.

Abstract: A process for liquefying natural gas in conjunction with processing natural gas to recover natural gas liquids (NGL) is disclosed. In the process, the natural gas stream to be liquefied is taken from one of the streams in the NGL recovery plant and cooled under pressure to condense it. A distillation stream is withdrawn from the NGL recovery plant to provide some of the cooling required to condense the natural gas stream. A portion of the condensed stream is expanded to an intermediate pressure and then used to provide some of the cooling required to condense the natural gas stream, and thereafter routed to the NGL recovery plant so that any heavier hydrocarbons it contains can be recovered in the NGL product. The remaining portion of the condensed stream is expanded to low pressure to form the liquefied natural gas stream.

Abstract: In a process for separating air in a system comprising a gas turbine, including a compressor (1), a combustor (5) and an expander (17), said expander being coupled to the compressor, a natural gas conversion unit (23) and an air separation unit (20), air is compressed in the compressor, a first part (3) of the air is sent to the combustor and a second part (7) of the air is sent to the air separation unit, oxygen enriched gas (21) is sent from the air separation unit to the natural gas conversion unit, compressed nitrogen enriched gas (16) is sent upstream of the expander, a first stream (33) of natural gas is sent to the natural gas conversion unit, a second stream of natural gas (35) is sent to a natural gas liquefaction unit and work produced by the expander is used to operate a cycle compressor of a refrigeration cycle of the natural gas liquefaction unit.

Abstract: In an integrated process and apparatus for the separation of air by cryogenic distillation and liquefaction of natural gas in which at least part of the refrigeration required to liquefy the natural gas is derived from at least one cryogenic air distillation plant comprising a main heat exchanger (7) and distillation columns (15, 17), wherein the natural gas (25) liquefies by indirect heat exchange in a heat exchanger (7, 32, 34) with a cold fluid (21, 26), the cold fluid being sent to the heat exchanger at least partially in liquid form and undergoing at least a partial vaporisation in the heat exchanger.

Abstract: A process is provided for converting a boil-off stream comprising methane to a liquid having a preselected bubble point temperature. The boil-off stream is pressurized, then cooled, and then expanded to further cool and at least partially liquefy the boil-off stream. The preselected bubble point temperature of the resulting pressurized liquid is obtained by performing at least one of the following steps: before, during, or after the process of liquefying the boil-off stream, removing from the boil-off stream a predetermined amount of one or more components, such as nitrogen, having a vapor pressure greater than the vapor pressure of methane, and before, during, or after the process of liquefying the boil-off stream, adding to the boil-off stream one or more additives having a molecular weight heavier than the molecular weight of methane and having a vapor pressure less than the vapor pressure of methane.

Abstract: A liquefaction system includes a source tank containing a supply of liquid nitrogen with a head space there above filled with nitrogen vapor. A pump transfers the liquid nitrogen to a heat exchanger. The heat exchanger also receives natural gas that has been processed in a purifier. The natural gas is liquefied by free cold from the liquid nitrogen so that liquid natural gas (LNG) is produced. The LNG travels to an LNG destination tank for storage and/or transport. The liquid nitrogen is vaporized in the heat exchanger. The resulting nitrogen gas is directed to a process system that may include, for example, cylinders for welding or other applications. Between liquefaction cycles, the purifier is regenerated by a vacuum and nitrogen vapor from the head space of the source tank. Steel shot is mixed with absorbent in the purifier so that the absorbent is cooled for increased performance.

Abstract: Plant (1) for liquefying natural gas comprising a main heat exchanger (10) in which the natural gas (5) is liquefied by means of indirect heat exchange with evaporating refrigerant, and a refrigerant circuit (20) in which evaporated refrigerant is compressed (23a, 23b) and liquefied to produce liquid refrigerant that is used in the main heat exchanger (10), wherein the refrigerant circuit (20) includes a compressor train (23a, 23b) consisting of at least one compressor (65a-67b) driven by an electric motor (83a, 83b).

Abstract: A system and apparatus for condensing boil-off vapor from a Liquified Natural Gas (LNG) container are disclosed. A system for condensing vapor includes the steps of providing contact area within a condenser vessel, directing vapor to the condenser vessel, providing a condensing fluid and a pump fluid, directing the condensing fluid to the condenser vessel, varying the flow of the condensing fluid to control the pressure in the vessel, contacting the vapor with the condensing fluid to create a condensate, and combining the condensate and the pump fluid. An apparatus for condensing vapor includes a vessel, a liquified gas input to the vessel, control means on the liquified gas input for varying a first liquified gas stream to control the pressure in the vessel, a vapor input to the vessel, means for condensing vapor in the vessel, and means for combining condensed vapor with a second liquified gas stream.

Abstract: Liquefied natural gas is stored in an insulated tank, typically forming part of an ocean going tanker. Boiled off vapour is compressed in a compressor and at least partially condensed in a condenser. The resulting condensate is returned to the tank. The vapour is mixed with liquefied natural gas in a mixing chamber upstream of the compressor. The liquefied natural gas so mixed with the vapour in the mixing chamber is taken from the condensate or from the storage tank.

Abstract: A method and apparatus for refrigerating and, if desired, liquefying an industrial gas wherein a multicomponent refrigerant fluid is used to generate refrigeration in a single circuit which includes a single phase separation and recycle after an initial heat exchange stage.

Abstract: This invention concerns a method and an apparatus for improving the efficiency of an open-cycle refrigeration process for LNG production by the employment of a liquid expander to recover energy associated with the flashing of a pressurized liquid stream and employing said recovered energy to compress the flashed vapor streams in the open cycle.

Abstract: A station for dispensing a gas, in particular nitrogen, under a dispensing pressure, includes a line (10) for gas inlet under an inlet high pressure, a line (14) for dispensing the gas under a lower dispensing pressure, and a device (16) for reducing the pressure of the gas to be dispensed from the inlet pressure to the dispensing pressure. The pressure-reducing device (16) includes a machine for pressure reduction with external work production. The station includes upstream of the pressure-reducing device (16), a conduit (18) for dividing the inlet gas into a fraction to be dispensed and a complementary fraction, downstream of the conduit (18), a device (20) for liquefaction of the complementary fraction of the inlet gas that includes a heat exchanger (26) for exchanging heat with the reduced-pressure fraction of the inlet gas, and a reservoir (40) for collecting the liquefied complementary fraction.

Abstract: A method of liquefaction/conditioning of a compressed gas/condensate flow extracted from a petroleum deposit, for transport in liquefied form with a transport vessel, especially for such processing of a compressed gas/condensate flow which has been separated from a crude oil extracted from an offshore oil field. The gas/condensate flow is depressurized and cooled in several steps for producing a stabilized liquefied natural gas (LNG) and a stabilized liquefied petroleum gas (LPG), for transport thereof in separate tanks.

Abstract: Provided is a gas recovery unit which is more efficient in its recovery and less expensive to run. The gas recovery unit comprises a CVD device, an exhaust gas recovery part and an exhaust gas purification part. The exhaust gas recovery part is constructed so as to have an inert gas reservoir part capable of accommodating liquid nitrogen, to have an exhaust gas supply part for supplying an exhaust gas to said inert gas reservoir part so that it can be brought in gasliquid contact with the liquid nitrogen, and to have a recovered and liquefied gas discharge part for discharging the recovered and liquefied gas which has been liquefied in the inert gas reservoir part.

Abstract: A method of draining a tank that has been containing liquid gas, and a plant for use in such draining. After draining of the major part of the tank contents, but while residual contents of gas are present in vapourized state in the tank, the residual contents are conveyed for exchanging heat directly or indirectly with cold nitrogen. Nitrogen is vapourized and heated and conveyed to the tank, while the residual gas is cooled and condensed and conveyed to a collector tank. The plant comprises a heat exchange system connected to the supply of nitrogen, and residual gas is forced from the tank to be drained and through the heat exchange system in order to cause vapourization and heating of nitrogen to be conveyed to the tank, in such a manner that the residual gas from the tank condenses, whereby a collector container is connected for receiving condensed residual gas.

Abstract: A fluid consisting at least partly of a mixture of hydrocarbons is liquefied by means of the following stages:the mixture under pressure is cooled so as to condense it at least partly to produce a liquid phase and a gas phase, and bringing into contact of at least a fraction of each of said phases is simultaneously achieved at least partly in a countercurrent flow so as to obtain, by matter transfer, a gas phase enriched in light hydrocarbons and a first liquid phase enriched in heavy hydrocarbons, andthe two phases obtained thereby are separated and the gas phase enriched in light hydrocarbons is sent to a second cooling stage in order to obtain a second liquid phase enriched in light hydrocarbons.

Abstract: Two heat exchangers are hooked up together in order to generate a flow of cold gas. A deep-frozen liquefied medium is evaporated in the first heat exchanger (1) by means of heat exchange with a heat transfer medium. The evaporated medium is re-cooled in the second heat exchanger. The deep-frozen liquefied cryogenic medium used for this purpose is likewise evaporated in this process. The two flows of gas thus generated are conveyed to a mixing site and then combined to form a flow of cold gas.

Abstract: An ethane-rich fraction for refilling the refrigerant circuit, using an ethane-containing refrigerant in a process for liquefaction of a hydrocarbon-rich fraction, is obtained by removing a partial flow of liquefied hydrocarbon-rich fraction and supplying same to a C.sub.1 /C.sub.2 /C.sub.3+ separation column. Roughly in the middle of this C.sub.1 /C.sub.2 /C.sub.3+ separation column, an ethane-rich fraction is withdrawn and, optionally after intermediate storage in a buffer tank, is added to the ethane-containing refrigerant.

Abstract: A pressurized hydrocarbon-rich fraction is cooled and liquefied by heat exchange with the process flows to be heated. Thereafter, the fraction is expanded in an expansion valve and introduced into a storage tank. The flash gas/boil-off gas removed from the storage tank, which optionally forms one of the process flows to be heated, is compressed in one or more stages. The throughput of the flash gas/boil-off gas compressor is kept constant at full load via the position of the expansion valve or expansion turbine controlled by means of a FIC controller. The pressure following expansion valve or expansion turbine is kept substantially constant.

Abstract: A pressurized natural gas flow, from which CO.sub.2 and H.sub.2 O are first removed using an adsorptive separation device, is subjected to liquefaction. The pre-purified natural gas flow is brought into heat exchange with at least one refrigerant routed in a refrigeration circuit and liquefied. The adsorptive separation device is regenerated by means of a regeneration gas containing a partial flow of the pre-purified natural gas flow and optionally additional residual gas flows such as a flash gas flow. During the cooling and liquefaction process of the natural gas flow at least the partial natural gas flow needed-for regeneration of the adsorptive separation device is separated when the temperature of the partial flow is such that the efficiency of cold use can be maximized by throttling to the regeneration gas pressure.