Abstract: A process of liquefying a gaseous, methane-rich feed to a liquefied product is provided that includes adjusting the composition and the amount of refrigerant and controlling the liquefaction process using an advanced process controller based on model predictive control to determine simultaneous control actions for a set of manipulated variables.

Abstract: Disclosed are methods for efficiently and economically designing, constructing, or operating a light hydrocarbon gas liquefaction process for the liquefaction of selected quantities of light hydrocarbon gas. The method includes a light hydrocarbon gas liquefaction launch train to liquefy an initial amount of light hydrocarbon gas and one or more optional subsequent modular expansion phases to said light hydrocarbon gas liquefaction train to liquefy additional selected quantities of light hydrocarbon gas up to a selected maximum quantity of light hydrocarbon gas for the process. The methods employ shared use facilities, such as light hydrocarbon feed gas pretreatment facilities, refrigerant compression facilities, cryogenic heat exchange facilities, access services, other liquefaction equipment, and liquefied product storage and shipping facilities.

Abstract: A reduced carbon dioxide emission system and method for providing power for refrigerant compression and shared electrical power for a light hydrocarbon gas liquefaction process.

Abstract: A method for liquefying methane-rich gas in the form of a feed gas comprising the steps of cooling the gas and partially liquefying the gas by expansion within an expansion device. The pressure of the gas at the inlet of the expansion device is in the range from 40 bar to 100 bar and pressure of the gas at the outlet of the expansion device is in the range from 2 bar to 10 bar.

Abstract: Raman spectrometers are employed in a hydrocarbon processing plant for online measurement of at least one compositional property of a hydrocarbon stream. The Raman spectrometers can be used to control separations equipment, determine energy content, and/or determine flow rate. The Raman spectrometers are especially advantageous when employed in a liquefied natural gas (LNG) plant to determine properties of cooled natural gas streams.

Abstract: A process for liquefying natural gas in conjunction with producing a liquid stream containing predominantly hydrocarbons heavier than methane is disclosed. In the process, the natural gas stream to be liquefied is partially cooled, expanded to an intermediate pressure, and supplied to a distillation column. The bottom product from this distillation column preferentially contains the majority of any hydrocarbons heavier than methane that would otherwise reduce the purity of the liquefied natural gas. The residual gas stream from the distillation column is compressed to a higher intermediate pressure, cooled under pressure to condense it, and then expanded to low pressure to form the liquefied natural gas stream.

Abstract: A cryogenic refrigerator includes a pressure feeding device, a refrigeration device, a high pressure passage, a low pressure passage, and at least one heat exchanger at the high pressure passage for refrigerating the refrigerant introduced at the high pressure passage by heat exchange, the heat exchanger including an active pressure drop type heat exchanger for declining pressure of the refrigerant at the high pressure passage before being introduced into the refrigeration device. The active pressure drop type heat exchanger declines the pressure of the refrigerant with a ratio equal to or greater than 5 percent out of 100 percent and refrigerates the refrigerant when a pressure difference between a pressure of the refrigerant before being introduced into the active pressure drop type heat exchanger and a pressure of the refrigerant before being introduced into the refrigeration device is defined as 100 percent.

Abstract: A process for liquefying natural gas in conjunction with producing a liquid stream containing predominantly hydrocarbons heavier than methane is disclosed. In the process, the natural gas stream to be liquefied is partially cooled and divided into first and second streams. The first stream is further cooled to condense substantially all of it, expanded to an intermediate pressure, and then supplied to a distillation column at a first mid-column feed position. The second stream is also expanded to intermediate pressure and is then supplied to the column at a second lower mid-column feed position. A distillation stream is withdrawn from the column below the feed point of the second stream and is cooled to condense at least a part of it, forming a reflux stream. At least a portion of the reflux stream is directed to the distillation column as its top feed.

Abstract: A refrigeration process is disclosed that employs a mixed refrigerant to chill a process gas stream in which a second stream is cooled against rewarming vaporized mixed refrigerant at low pressure and subsequently is at least partially vaporized against at least partially condensed mixed refrigerant at a higher pressure.

Abstract: Method for gas liquefaction comprising cooling a feed gas by a first refrigeration system in a first heat exchange zone and withdrawing a substantially liquefied stream therefrom, further cooling the substantially liquefied stream by indirect heat exchange with one or more work-expanded refrigerant streams in a second heat exchange zone, and withdrawing therefrom a further cooled, substantially liquefied stream. At least one of the one or more work-expanded refrigerant streams is provided by compressing one or more refrigerant gases to provide a compressed refrigerant stream, cooling all or a portion of the compressed refrigerant stream in a third heat exchange zone to provide a cooled, compressed refrigerant stream, and work expanding the cooled, compressed refrigerant stream to provide one of the one or more work-expanded refrigerant streams.

Abstract: Improved methodology for starting up a LNG facility employing a refluxed heavies removal column. The improved methodology involves varying the temperature of the feed to the heavies removal column between start-up and normal operation. This allows a larger amount of the stream produced from the top of the heavies removal column during start-up to be used to more rapidly start up the LNG facility.

Abstract: The invention concerns a method comprising: (a) a first step whereby natural gas (1) is subjected to a first refrigerating cycle to obtain cooled natural gas (4), and brought to a temperature less than 20° C. by a first coolant (201); a second step whereby the cooled natural gas (4) is subjected to a second refrigerating cycle wherein the cooled natural gas (4) is cooled and condensed by a second coolant (103) comprising methane, ethane, propane, and nitrogen. The second coolant (103) further contains ethylene, the total ethane and ethylene content being close to 50 mole %.

Abstract: Method for liquefying a gas which comprises cooling a feed gas stream successively through first and second temperature ranges to provide a liquefied product, wherein refrigeration for cooling the feed gas stream in the first temperature range is provided by a first vaporizing refrigerant and refrigeration for cooling the stream in the second temperature range is provided by a second vaporizing refrigerant, and further wherein an auxiliary refrigerant derived from the second vaporizing refrigerant provides additional refrigeration by vaporization at temperatures above a lowest temperature in the first temperature range.

Abstract: The recovery of ethylene from light gases at low temperature by the use of a mixed refrigeration system comprising methane, ehtylene and/or ethane, and propylene and/or propane.

Abstract: Refrigerant freezeout is prevented by the use of a controlled bypass flow that causes a warming of the lowest temperature refrigerant in a refrigeration system that achieves very low temperatures by using a mixture of refrigerants comprising at least two refrigerants with boiling points that differ by at least 50° C. This control capability enables reliable operation of the very low temperature system.

Abstract: This invention relates to a process for cooling or liquefying a fluid product (e.g., natural gas) in a heat exchanger, the process comprising: flowing a fluid refrigerant through a set of refrigerant microchannels in the heat exchanger; and flowing the product through a set of product microchannels in the heat exchanger, the product flowing through the product microchannels exchanging heat with the refrigerant flowing through the refrigerant microchannels, the product exiting the set of product microchannels being cooler than the product entering the set of product microchannels. The process has a wide range of applications, including liquefying natural gas.

Abstract: Compressor system comprising (a) a first compressor having a first stage and a second stage wherein the first stage of the first compressor is adapted to compress a first gas and the second stage of the first compressor is adapted to compress a combination of a fourth gas and an intermediate compressed gas from the first stage of the first compressor; and (b) a second compressor having a first stage and a second stage wherein the first stage of the second compressor is adapted to compress a second gas and the second stage of the second compressor is adapted to compress a combination of a third gas and an intermediate compressed gas from the first stage of the second compressor. The first gas is at a first pressure, the second gas is at a second pressure higher than the first pressure, the third gas is at a third pressure higher than the second pressure, and the fourth gas is at a fourth pressure higher than the third pressure.

Abstract: Improved methodology for starting up a LNG facility employing a refluxed heavies removal column. The improved methodology involves varying the temperature of the feed to the heavies removal column between start-up and normal operation. This allows a larger amount of the stream produced from the top of the heavies removal column during start-up to be used to more rapidly start up the LNG facility.

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: A method for liquefying methane-rich gas in the form of a feed gas comprising the steps of cooling the gas and partially liquefying the gas by expansion within an expansion device. The pressure of the gas at the inlet of the expansion device is in the range from 40 bar to 100 bar and pressure of the gas at the outlet of the expansion device is in the range from 2 bar to 10 bar.

Abstract: The invention concerns a method comprising: (a) a first step whereby natural gas (1) is subjected to a first refrigerating cycle to obtain cooled natural gas (4), and brought to a temperature less than 20° C. by a first coolant (201); a second step whereby the cooled natural gas (4) is subjected to a second refrigerating cycle wherein the cooled natural gas (4) is cooled and condensed by a second coolant (103) comprising methane, ethane, propane, and nitrogen. The second coolant (103) further contains ethylene, the total ethane and ethylene content being close to 50 mole %.

Abstract: This process includes the following steps:

Abstract: A gas pressurization system comprising a gas inlet valve configured to receive an inlet gas stream. A clean-up system is coupled to the gas inlet valve. A recovery heat exchanger coupled to the clean-up system. The recovery heat exchanger is configured to remove thermal energy from the inlet gas stream and cool the inlet gas stream to one of a pre-cooled gas and liquid stream. An expander coupled to the recovery heat exchanger is configured to expand the pre-cooled liquid stream. A refrigeration unit coupled to the expander and configured to cool the expanded pre-cooled liquid stream to a liquid phase. A buffer storage unit is coupled to the refrigeration unit. A pump is coupled to the buffer storage unit at a pump suction and has a pump discharge coupled to the recovery heat exchanger. A high-pressure storage unit coupled to the pump discharge downstream of the recovery heat exchanger.

Abstract: Method for liquefying a gas which comprises cooling a feed gas stream successively through first and second temperature ranges to provide a liquefied product, wherein refrigeration for cooling the feed gas stream in the first temperature range is provided by a first vaporizing refrigerant and refrigeration for cooling the stream in the second temperature range is provided by a second vaporizing refrigerant, and further wherein an auxiliary refrigerant derived from the second vaporizing refrigerant provides additional refrigeration by vaporization at temperatures above a lowest temperature in the first temperature range.

Abstract: Controlling the production of a liquefied natural gas comprising measuring the temperature and the flow rate of the liquefied natural gas; maintaining the flow rate of the heavy mixed refrigerant at an operator manipulated set point; and determining the flow rate of the light mixed refrigerant from the flow rate of the heavy mixed refrigerant and an operator manipulated set point for the ratio of the flow rate of the heavy mixed refrigerant to the flow rate of the light mixed refrigerant; determining a dependent set point for the ratio of the flow rate of the liquefied natural gas to the flow rate of the heavy mixed refrigerant such that the temperature of the liquefied natural gas is maintained at an operator manipulated set point; determining a dependent set point for the flow rate of the liquefied natural gas from the dependent set point for the ratio of the flow rate of the liquefied natural gas product stream to the flow rate of the heavy mixed refrigerant and the flow rate of the heavy mixed refrigerant

Abstract: Natural gas liquefaction method wherein the natural gas is cooled, condensed and subcooled by indirect heat exchange with two cooling mixtures to a temperature such that the natural gas does not remain entirely liquid under pressure after expansion to the atmospheric pressure. The liquid natural gas under pressure is expanded to form a gas phase and a liquid phase. The gas phase can be either compressed and recycled to the process inlet, or used as a fuel. The liquid phase is expanded to form a gas phase and a liquid phase. The gas phase is compressed and recycled to the process inlet. The liquid phase constitutes the liquefied natural gas produced.

Abstract: A reduced carbon dioxide emissions system and method for providing power for refrigerant compression and shared electrical power for a light hydrocarbon gas liquefaction process.

Abstract: A reduced carbon dioxide emission system and method for providing power for refrigerant compression and shared electrical power for a light hydrocarbon gas liquefaction process.

Abstract: Method and process plant for liquefaction of gas, particularly natural gas with multicomponent refrigerant, suited for small and medium sized scale, where the plant solely is based on conventional two-flow plate heat exchangers and conventional oil lubricated compressors. By the arrangement of the heat exchangers and the compressors according to the invention it is avoided that oil from the compressors, that to some extend will follow the flow of refrigerant, may reach the coldest parts of the plant. Any freezing of oil and plugging of conduit etc. is thus avoided.

Abstract: Described is a process and a device for liquefying hydrogen, whereby the hydrogen to be liquefied is liquefied against one or more refrigerant (mixture) circuits and/or by means of expansion and is guided over at least one ortho-para conversion catalyst.

Abstract: Method for liquefying a gas which comprises cooling a feed gas stream successively through first and second temperature ranges to provide a liquefied product, wherein refrigeration for cooling the feed gas stream in the first temperature range is provided by a first vaporizing refrigerant and refrigeration for cooling the stream in the second temperature range is provided by a second vaporizing refrigerant, and further wherein the second vaporizing refrigerant provides additional refrigeration by vaporization at temperatures above a lowest temperature in the first temperature range.

Abstract: Controlling the production of a liquefied natural gas consist of measuring the temperature and the flow rate of the liquefied natural gas; maintaining the flow rate of the heavy mixed refrigerant at an operator manipulated set point, and determining the flow rate of the light mixed refrigerant from the flow rate of the heavy mixed refrigerant and an operator manipulated set point for the ratio of the flow rate of the heavy mixed refrigerant to the flow rate of the light mixed refrigerant; determining a dependent set point for the ratio of the flow rate of the liquefied natural gas to the flow rate of the heavy mixed refrigerant such that the temperature of the liquefied natural gas is maintained at an operator manipulated set point; determining a dependent set point for the flow rate of the liquefied natural gas from the dependent set point for the ratio of the flow rate of the liquefied natural gas product stream to the flow rate of the heavy mixed refrigerant and the flow rate of the heavy mixed refrigerant

Abstract: A system for liquefying natural gas by cooling the natural gas stream in a first refrigeration cycle employing a non-volatile refrigerant, such as carbon dioxide, and subsequently cooling the natural gas stream in a second refrigeration cycle employing a predominately methane refrigerant.

Abstract: The refrigeration system for an ethylene plant comprises a closed loop tertiary refrigerant system containing methane, ethylene and propylene. The tertiary refrigerant from a compressor final discharge is separated into a methane-rich vapor fraction and two levels of propylene-rich liquids so as to provide various temperatures and levels of refrigeration in various heat exchange stages while maintaining a nearly constant refrigerant composition flowing back to the compressor and with the bulk of the total return refrigerant flow going to the first stage compressor section. This tertiary system can also be applied to an ethylene plant with a high pressure demethanizer.

Abstract: A gas liquefaction method which uses the pressure energy of a natural gas processing system to generate refrigeration for high temperature cooling of a gas, and uses a mixed gas refrigerant fluid to generate refrigeration for low temperature cooling of the gas to produce liquefied product.

Abstract: Natural gas liquefaction system having an optimum configuration of mechanical drivers and compressors. A heat recovery system can be employed with the liquefaction system to enhance thermal efficiency. A unique start-up system can also be employed.

Abstract: Natural gas liquefaction method wherein the natural gas is cooled, condensed and subcooled by indirect heat exchange with two cooling mixtures to a temperature such that the natural gas does not remain entirely liquid under pressure after expansion to the atmospheric pressure. The liquid natural gas under pressure is expanded to form a gas phase and a liquid phase. The gas phase can be either compressed and recycled to the process inlet, or used as a fuel. The liquid phase is expanded to form a gas phase and a liquid phase. The gas phase is compressed and recycled to the process inlet. The liquid phase constitutes the liquefied natural gas produced.

Abstract: A process and apparatus for exploitation and liquefaction of natural gas in offshore stranded gas reserves. Two ordinary nautical vessels are used to produce, store and unload LPG and LNG. Typical front end processing is performed on the first vessel. The treated inlet gas is transported to the second vessel where the stream goes through liquefaction and storage until it is offloaded to a transport vessel for shipment. The liquefaction process utilizes two refrigerant cycles that utilize two expanded refrigerants, at least one of which is circulated in a gas phase refrigeration cycle. The refrigerants and the inlet gas stream are transported between the two vessels by the use of piping. Electricity can be generated to provide power for the compression sections of the refrigeration cycles. Turbines, engines, or boilers from the vessels can be used for generating electricity since they are no longer needed for locomotion purposes.

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

Abstract: Natural gas liquefaction systems are provided wherein the dedicated compression strings normally found in each liquefaction train of a multi-train LNG plant are replaced by common compression strings which, in turn, supply the respective refrigerants (e.g. propane and mixed refrigerant) to more than one of the multi-trains. This allows the refrigerants to be treated as a utility in that all of the refrigerants are supplied from a respective single source by the common compression strings.

Abstract: A closed circuit refrigeration system of successive coalescent/depth filters provides the almost total removal of liquid refrigerants from a refrigeration gas stream. The liquid refrigerant so extracted is then be returned to the suction side through a metering device such as a capillary line to provide intermediate cooling of the oncoming discharge gas. The auto cascade system utilizes short path plate heat exchangers. The properties of coalescent/depth filters place a physical barrier between the differing temperature/pressure regimes on the discharge side of the system. The provision of a start valve in a line connecting the gas discharge path and the return path close to the cryo-coil enables the use of hermetic compressors and eliminates the requirement for supplementary pressure vessels within auto-cascade cryogenic refrigeration systems.

Abstract: Natural gas liquefaction system employing electric motors as compressor drivers. A combination of motors and steam turbines can be powered by a cogeneration plant and employed as drivers.

Abstract: The refrigeration system for an ethylene plant comprises a closed loop tertiary refrigerant system containing methane, ethylene and propylene. The tertiary refrigerant from a compressor is separated into an inter-stage discharge and the final compressor discharge to produce a methane-rich vapor fraction and two levels of propylene-rich liquids so as to provide various temperatures and levels of refrigeration in various heat exchange stages while maintaining a nearly constant refrigerant composition flowing back to the compressor and with the bulk of the total return refrigerant flow going to the first stage compressor section. This tertiary system can also be applied to an ethylene plant with a high pressure demethanizer.

Abstract: The refrigeration system for an ethylene plant comprises a closed loop tertiary refrigerant system containing methane, ethylene and propylene. The tertiary refrigerant from a compressor final discharge is separated into a methane-rich vapor fraction and two levels of propylene-rich liquids so as to provide various temperatures and levels of refrigeration in various heat exchange stages while maintaining a nearly constant refrigerant composition flowing back to the compressor and with the bulk of the total return refrigerant flow going to the first stage compressor section. This tertiary system can also be applied to an ethylene plant with a high pressure demethanizer.

Abstract: The refrigeration system for an ethylene plant comprises a closed loop tertiary refrigerant system containing methane, ethylene and propylene. The tertiary refrigerant from a compressor is separated into an inter-stage discharge and the final compressor discharge to produce a methane-rich vapor fraction and two levels of propylene-rich liquids so as to provide various temperatures and levels of refrigeration in various heat exchange stages while maintaining a nearly constant refrigerant composition flowing back to the compressor and with the bulk of the total return refrigerant flow going to the first stage compressor section. This tertiary system can also be applied to an ethylene plant with a high pressure demethanizer.

Abstract: Natural gas liquefaction system employing a zeolite adsorbent for removing nitrogen from pretreated natural gas.

Abstract: The present invention provides a cryogenic refrigerating system for achieving ultra low temperature by sequentially obtaining low temperature through repetition of expansion and evaporation of a mixed-refrigerant in multiple stages. The refrigerating system includes a heat exchanger and a compressor between a final evaporator and a compressor. The heat exchanger causes evaporated refrigerant vapor in a suction tube for the compressor to be heated and to be drawn into the compressor, and causes the refrigerant condensed by a condenser to be supercooled. The refrigerating system includes a plurality of expansion/suction apparatuses connected with one another between the gas/liquid separator and the final evaporator.

Abstract: Natural gas liquefaction systems are provided wherein the dedicated compression strings normally found in each liquefaction train of a multi-train LNG plant are replaced by common compression strings which, in turn, supply the respective refrigerants (e.g. propane and mixed refrigerant) to more than one of the multi-trains. This allows the refrigerants to be treated as a utility in that all of the refrigerants are supplied from a respective single source by the common compression strings.

Abstract: A method for providing refrigeration wherein a first multicomponent refrigerant is condensed to form a saturated liquid and vaporized against a condensing second multicomponent refrigerant which has a dew point less than the dew point and preferably the bubble point of the saturated liquid, and has a bubble point greater than that of the vaporizing first multicomponent refrigerant, and after providing refrigeration to a refrigeration load, may be superheated against the condensing first and second multicomponent refrigerants.

Abstract: Refrigeration process for gas liquefaction which utilizes one or more vaporizing refrigerant cycles to provide refrigeration below about ?40° C. and a gas expander cycle to provide refrigeration below about ?100° C. Each of these two types of refrigerant systems is utilized in an optimum temperature range which maximizes the efficiency of the particular system. A significant fraction of the total refrigeration power required to liquefy the feed gas (typically more than 5% and often more than 10% of the total) can be consumed by the vaporizing refrigerant cycles. The invention can be implemented in the design of a new liquefaction plant or can be utilized as a retrofit or expansion of an existing plant by adding gas expander refrigeration circuit to the existing plant refrigeration system.