Abstract: A method and system for liquefying a methane-rich high-pressure feed gas stream using a first heat exchanger zone and a second heat exchanger zone. The feed gas stream is mixed with a refrigerant stream to form a second gas stream, which is compressed, cooled, and directed to a second heat exchanger zone to be additionally cooled below ambient temperature. It is then expanded to a pressure less than 2,000 psia and no greater than the pressure to which the second gas stream was compressed, and then separated into a first expanded refrigerant stream and a chilled gas stream. The first expanded refrigerant stream is expanded and then passed through the first heat exchanger zone such that it has a temperature that is cooler, by at least 5° F., than the highest fluid temperature within the first heat exchanger zone.

Abstract: A system and method for producing an LNG product stream to provide fuel to generators, as an alternative to diesel, to power drilling and other equipment. Using sales gas from a natural gas/NGL plant containing less than 95% methane as a feed stream, production of LNG having 95% or more methane in quantities of 100,000 GPD or more LNG product are achievable with the system and method. The system and method preferably combine use of strategic heat exchange between the feed and a nitrogen-methane flash vapor stream and other streams within the LNG processing system without requiring heat exchange with process streams in the natural gas/NGL plant and a rectifier column that uses an internal knockback condenser and does not require a reboiler to remove heavier components from the sales gas feed.

Abstract: Liquefier arrangements configured for co-production of both liquid natural gas (LNG) and liquid nitrogen (LIN) configured to operate in two distinct operating modes are provided.

Abstract: The invention relates to a process and apparatus for producing nitrogen by low-temperature fractionation of air in a rectification system which has a high-pressure column (4) and a low-pressure column (5). Feed air (1, 3) is introduced into the high-pressure column (4). An oxygen-containing liquid fraction (11) is removed from the high-pressure column (4) and fed into the low-pressure column (5). Gaseous nitrogen (18) is extracted from the low-pressure column (5) above a mass transfer section (25), which has at least one theoretical or practical plate, and is at least partially condensed in a top condenser (17) by indirect heat exchange with a refrigerant (13). High-purity nitrogen is removed from the low-pressure column below the mass transfer section (25), and is obtained as a nitrogen product (26, 27, 30). The process and apparatus have a refrigeration-supply system, in which a refrigeration fluid (31) flows.

Abstract: A method for the recovery of hydrogen and one or more hydrocarbons having one or more carbon atoms from a feed gas containing hydrogen and the one or more hydrocarbons, which process comprises cooling and partially condensing the feed gas to provide a partially condensed feed; separating the partially condensed feed to provide a first liquid stream enriched in the one or more hydrocarbons and a first vapor stream enriched in hydrogen; further cooling and partially condensing the first vapor stream to provide an intermediate two-phase stream; and separating the intermediate two-phase stream to yield a further-enriched hydrogen stream and a hydrogen-depleted residual hydrocarbon stream. Some or all of the cooling is provided by indirect heat exchange with cold gas refrigerant generated in a closed-loop gas expander refrigeration cycle.

Abstract: A method for providing refrigeration to a cryogenic rectification plant which enables the facile provision of varying amounts of refrigeration to the plant wherein a working fluid is pressurized in a recycle compressor, a first portion is at least partially condensed in a heat exchanger and passed into the plant, a second portion is cooled and then turboexpanded to generate refrigeration, the refrigeration bearing second portion passes refrigeration in the heat exchanger to the first portion to effect the condensation, and the resulting second portion is not passed into the cryogenic rectification plant but rather is returned to the recycle compressor.

Abstract: A cryogenic rectification system wherein some or all of the refrigeration necessary to drive the rectification is generated by periodically magnetizing and demagnetizing a bed of magnetizable material, passing refrigerator gas through the bed to produce cold refrigerator gas, and passing refrigeration from the cold refrigerator gas into the rectification system.

Abstract: Apparatus (30) for compressing gaseous refrigerant for use in a refrigeration circuit (2) of a liquefaction plant, which refrigeration circuit (2) has an inlet (5), a first outlet (6) for refrigerant at low pressure, a second outlet (7) for refrigerant at intermediate pressure, a third outlet (8) for refrigerant at high pressure and a fourth outlet (9) for refrigerant at high-high pressure, which apparatus (30) comprises a first and a second compressor (31a, 31b), wherein the first compressor (31a) has a main inlet (36) connected to the first outlet (6), a side-inlet (37) connected to the third outlet (8) and an outlet (38) connected to the inlet (5) of the refrigeration circuit (2), and wherein the second compressor (31b) has a main inlet (39) connected to the second outlet (7), a side-inlet (40) connected to the fourth outlet (9) and an outlet (41) connected to the inlet (5) of the refrigeration circuit (2).

Abstract: A natural gas liquefaction system and process wherein excess refrigeration available in a typical natural gas liquefaction system is used to cool the inlet air to gas turbines in the system to thereby improve the overall efficiency of the system. A cooler is positioned in front of the air inlet of each gas turbine; and coolant (e.g. water) is flowed through each of the coolers to cool the ambient air as it flows into the gas turbines. The water, in turn, is cooled with propane taken from a refrigerant circuit in the system which, in turn, is used to initially cool the natural gas which is to be liquefied.

Abstract: The object of the present invention is to separate air at low power cost to produce high-pressure nitrogen gas and oxygen gas by utilizing cold of liquefied natural gas. Feed air is pre-purified and then introduced into a cryogenic separation unit, so that oxygen gas and nitrogen gas are separated. The nitrogen gas separated in the cryogenic separation unit is introduced into a second heat exchanger, and cooled by indirect heat exchange with a refrigerant. The nitrogen gas thus cooled is compressed in a low-temperature nitrogen compressor and supplied through a heater to an external plant for consumption. LNG is introduced into a first heat exchanger as a cold source. In the first heat exchanger, LNG cools and liquefies the refrigerant by indirect heat exchange. The liquefied refrigerant is sent to the second heat exchanger. The refrigerant is vaporized by indirect heat exchange with the nitrogen gas in the second heat exchanger. The vaporized refrigerant is returned to the first heat exchanger.

Abstract: A cryogenic rectification system wherein some or all of the refrigeration necessary to drive the rectification is generated by providing a pulse to a gas and then passing the compressed gas to a pulse tube wherein the gas expands in a wave generating refrigeration at one end of the pulse tube for transfer into the rectification system.

Abstract: C2 and C3 hydrocarbons, particularly ethylene and propylene, are recovered from refinery or petrochemical plant gas mixtures by cooling and fractionating a feed gas mixture containing these hydrocarbons and lighter components. Refrigeration for the process is provided by a closed-loop gas expander refrigeration process cycle which preferably uses nitrogen as the recirculating refrigerant. Cooling and fractionation may be effected in a dephlegmator.

Abstract: A cryogenic air separation process for producing liquid oxygen and other liquid products wherein refrigeration generation for the process is decoupled from the flow of process streams and is produced at least in part by at least on multicomponent refrigerant fluid refrigeration circuit.

Abstract: A cryogenic air separation process having improved flexibility and operating efficiency for producing elevated pressure gaseous oxygen by vaporizing pressurized liquid oxygen wherein refrigeration generation for the process is decoupled from the flow of process streams and is produced by one or more multicomponent refrigerant fluid circuits.

Abstract: A cryogenic air separation process having improved flexibility and operating efficiency wherein refrigeration generation for the process is decoupled from the flow of process streams and is produced by one or more closed loop circuits.

Abstract: A high pressure nitrogen pipeline, oxygen or plant air is diverted around a pressure letdown station to liquefy the gas or a portion of the gas for storage or air separation assist, with the remaining unused gaseous portion being returned to the pipeline downstream the letdown station. One or more heat exchangers and one or more expanders are used to cool down the gas and liquefy it. A generator or compressor may be coupled to the expanders employing companders for generating power or for further compression of the pipeline gas. In a further embodiment, natural gas is cooled to assist in liquefying the nitrogen by drying the natural gas and forming two streams wherein carbon dioxide is removed from a smaller stream which is applied to cascaded heat exchangers and the larger stream is expanded to further cool it. The two streams are applied to the heat exchangers for cooling and liquefying nitrogen gas or other merchant gas applied to the heat exchangers from a pipeline or other source.

Abstract: LPG and gasoline are recovered from catalytic reformer plant treat gas and net gas by refrigeration-induced condensation and separation, using reformer plant waste heat to produce the refrigeration in an ammonia absorption refrigeration unit. Referring to FIG. 2, reformer waste heat from exchanger 21 powers absorption refrigeration unit 22, which supplies refrigeration to chiller 25. Net gas and treat gas is recuperatively cooled in recuperator 24, chilled in chiller 25, and separated in separator 26. Absorption refrigeration may also be supplied to cool FCC compressor inlet vapor to below ambient, either in conjunction with treat gas chilling or independently. Other waste heat streams may also be used.

Abstract: Method for the liquefaction of a hydrocarbon-rich gas stream containing aromatic and heavy hydrocarbons, in particular a natural gas stream, where, prior to the liquefaction, a separation of the aromatic and the heavy hydrocarbons, in particular the C.sub.5+ hydrocarbons, comprisesa) a fraction (9, 11, 14) containing heavy hydrocarbons is admixed to the hydrocarbon-rich gas stream (1) to be liquefied,b) this mixed fraction (1, 2) is supplied to a separator (D),c) a gas fraction (3) freed of aromatic and heavy hydrocarbons is withdrawn from separator (D) and liquefied (E2), andd) a liquid fraction (5) enriched with aromatic and heavy hydrocarbons is withdrawn from separator (D).

Abstract: A refrigerating mixture is compressed in the penultimate stage of a plurality of stages of a compression unit. The mixture is partially condensed in order to cool it substantially to ambient temperature; the condensed mixture is separated in order to obtain a vapour fraction and a liquid fraction; the vapour fraction is cooled and partially condensed; the resultant vapour fraction is sent to the final compression stage at least the high pressure vapour fraction and the liquid fraction are cooled, expanded, and circulated in at least first heat exchange means (5) with the fluid to be cooled.Moreover, according to the invention, during condensation of the vapour fraction, the vapour fraction produced by separating the condensed mixture is cooled by circulating it in heat-exchange relationship with a refrigerating fluid, in second heat exchange means.

Abstract: A natural gas liquefaction process comprises passing natural gas through a series of heat exchangers in countercurrent relationship with a gaseous refrigerant circulated through a work expansion cycle. The work expansion cycle comprises compressing the refrigerant, dividing and cooling the refrigerant to produce at least first and second cooled refrigerant streams, substantially isentropically expanding the first refrigerant stream to a coolest refrigerant temperature, substantially isentropically expanding the second refrigerant stream to an intermediate refrigerant temperature warmer than said coolest refrigerant temperature, and delivering the refrigerant in the first and second refrigerant streams to a respective heat exchanger for cooling the natural gas through corresponding temperature ranges.

Abstract: The process allows to liquefy a gaseous mixture consisting at least partly of a mixture of hydrocarbons, such as a natural gas, by using a cooling mixture that is obtained, after a first cooling step, in a state referred to as "condensed single-phase" state.

Abstract: A process and apparatus are used for liquefying a low-boiling gas, 1, 507, particularly nitrogen. Gas to be liquified is cooled 12 under an increased pressure, is expanded 14 and is then obtained as a liquid product 16. In a refrigeration cycle, cycle medium is compressed to a first pressure 4, 6, 8, 10. A first partial flow 101 of the cycle medium is expanded while carrying out work in a first expansion machine 102. A second partial flow 201 of the cycle medium is cooled 12a and is expanded while carrying out work in a second expansion machine 202. In addition, a third partial flow 301 of the cycle medium is cooled and is expanded in a third expansion machine 302 while carrying out work. All three expansion machines 102, 202, 302 have essentially the same inlet pressure. The cooling of the gas to be liquified is carried out at least partially by the indirect heat exchange with expanded cycle medium 103, 203, 17 in a cycle heat exchanger 12.

Abstract: A process for producing a liquefied natural product such as LNG is described where a single phase nitrogen refrigerant is used in such a way that the refrigerant stream (10) is divided into at least two separate portions (12, 14) which are passed through separate turbo-expanders (106, 108) before being admitted to separate heat exchangers (103, 104) so that the warming curve of the refrigerant more closely matches the cooling curve of the product being liquefied so as to minimize thermodynamic inefficiencies and hence power requirements involved in operation of the method.

Abstract: A process is shown for producing liquefied natural gas from a pressurized natural feed stream. The feed stream is introduced into heat exchange contact with a mechanical refrigeration cycle to cool the feed stream to a first cooling temperature. At least a portion of the feed stream is passed through a turboexpander cycle to provide auxiliary refrigeration for the mechanical refrigeration cycle to thereby cool the feed stream to a second, relatively lower cooling temperature.

Abstract: The present invention is a process of high efficiency rectification zone separation of cracked or other ethylene-containing gas chilled primarily by two closed mixed refrigerant loops and at least part of the dephlegmated overhead gas. The composition of the mixed refrigerants is optimally chosen to obtain an extremely close approach between the process condensation temperatures in the high efficiency rectification zone and the temperature of the chilling streams. An approach of about 3.degree. F. to 8.degree. F. can be achieved for the full condensation curve in the high efficiency rectification zone operating with either ethane or naphtha derived cracked gas. Highly reliable and stable operation is obtained by closed refrigeration loops in the present invention, in addition to reducing high efficiency rectification zone design cost.

Abstract: A method and apparatus for generating nitrogen from the separation of air in a single column nitrogen generator. Nitrogen rich vapor is condensed to form reflux through the vaporization of an oxygen-rich liquid stream produced as column bottoms. The vaporized oxygen-rich stream is in part recompressed in a recycle compressor, cooled and reintroduced back into the column to increase nitrogen production. The vaporized oxygen-rich stream is also in part expanded with the performance of work. The work of expansion is applied to the compression. A supplemental refrigerant stream produced by a nitrogen liquefaction unit allows the nitrogen to be taken as a liquid and increases the amount of work of expansion able to be applied to the compression.

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 vapor recovery system is provided which includes a vapor recovery cycle and a regeneration cycle. The vapor recovery is condensation of the vapors in an air-vapor mixture utilizing a chiller cooled by a refrigerant gas to condense and remove vapor and to vent the air. The refrigerant cooling is provided by a compression-condensation-expansion refrigeration cycle. During the vapor recovery cycle ice tends to build up in the chiller due to the small amounts of water contained in the air-vapor mixture. In the regeneration cycle the hot refrigerant gas from the compressor by-passes the condenser and expansion valve to heat the "chiller", which heats the air-vapor mixture and melts any accumulated ice. During the regeneration cycle there is no venting and the entire air-vapor mixture is recycled to the chiller until the regeneration is completed. In addition to heating and meting ice in the system, the heated air-vapor mixture may be used to dry and regenerate desiccant material in the system.

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.