摘要:
Method and apparatus for producing a cooled hydrocarbon stream (60). The method employs cooling, at at least two consecutive pressure levels, a first stream and a first mixed refrigerant stream, using portions of the first mixed refrigerant from the first mixed refrigerant stream in first and second heat exchangers (125, 145); first and second expansion devices (135, 165); and a first compressor (105) to provide the first mixed refrigerant stream. The cooling process is controlled using an advanced process controller based on model predictive control to determine simultaneously control actions for a set of manipulated variables in order to optimise at least one of a set of parameters whilst controlling at least one of a set of controlled variables. The set of manipulated variables comprises: the composition of the mixed first refrigerant, the setting of the first expansion device (135), and the setting of the second expansion device (165).
摘要:
Procédé de refroidissement/liquéfaction à basse température d'un gaz de travail à faible masse molaire, le procédé utilisant un premier réfrigérateur/liquéfacteur (1) comprenant une station (2) de compression du gaz de travail et une boîte froide (3) destinée à refroidir le gaz de travail en sortie de la station (2) de compression, le procédé comportant : - une étape de compression, - une étape de refroidissement du gaz de travail comprimé lors de l'étape de compression, l'étape de compression utilisant à la fois des machines de compression du type à vis lubrifiées (EC1, EC2) et de machines de compression de type centrifuge (EC3, EC4), le procédé étant caractérisé en ce que l'étape de compression utilise sélectivement au moins une machine de compression (EC3) appartenant à une station de compression (12) d'un second réfrigérateur/liquéfacteur (11) distinct dudit premier réfrigérateur/liquéfacteur (1), le second réfrigérateur/liquéfacteur (11) utilisant un fluide de travail de même nature que celui du premier réfrigérateur/liquéfacteur (1).
摘要:
A refrigeration cycle system is provided, comprising a plurality of compressors (3,4,5) for compressing a refrigerant that is used to cool a medium (10), one of the compressors being a low pressure compressor (3), another one of the compressors being a high pressure compressor (5); a condenser (6) for cooling and condensing the refrigerant compressed by the plurality of compressors (3,4,5); a reservoir (7) for receiving the refrigerant condensed by the condenser (6); an expansion mechanism (9) for expanding and cooling the refrigerant supplied from the reservoir (7); an evaporator (9) for evaporating the refrigerant cooled by the expansion mechanism (8) by means of the medium (10) to generate a refrigerant to be supplied to the plurality of compressors (3,4,5); and an intercooler (15,15A,61) that is provided between the low pressure compressor (3) and the high pressure compressor (5) and adapted to cool the refrigerant supplied from the low pressure compressor (3) by means of the refrigerant supplied from the expansion mechanism (8) so as to generate a refrigerant to be supplied to the high pressure compressor (5).
摘要:
The present invention provides a method and apparatus (1) for producing a liquefied natural gas stream (100), wherein a natural gas stream (10) is cooled in a heat exchanger (2) against a refrigerant fluid being cycled in a refrigerant circuit (3). The cycling of the refrigerant fluid comprises: (a) feeding a first refrigerant fluid (20) into an axial compressor (5); (b) compressing the first refrigerant fluid (20) in the axial compressor (5), thereby obtaining a compressed first refrigerant fluid (30); (c) feeding the compressed first refrigerant fluid (30) at a first pressure level into a centrifugal compressor (6); (d) feeding a second refrigerant fluid (40) at a second pressure level being lower than the first pressure level into the centrifugal compressor (6); (e) compressing the compressed first refrigerant fluid (30) and the second refrigerant fluid (40) in the centrifugal compressor (6), thereby obtaining a compressed refrigerant fluid mixture (50); (f) cooling the compressed refrigerant fluid mixture (50) in a heat exchanger (13), thereby obtaining a cooled compressed refrigerant fluid mixture (60); (g) separating the cooled compressed refrigerant fluid mixture (60) into at least two streams; (h) evaporating the two streams obtained in step (g) at different locations of a heat exchanger (2) in heat exchanging contact with the natural gas stream (10) to be cooled; and (i) retrieving the first and second refrigerant fluids (20,40) from the two streams evaporated in step (h).
摘要:
The method involves compressing a coolant mixture in a pre-final stage (1A) through a series of stages of a compression unit (1). The mixture is condensed partially by cooling, and then is separated to produce a vapour fraction and a liquid fraction. The vapour fraction is cooled and partially condensed, and then passed through a final compression stage (1C) to obtain a high-pressure vapour. Part of the high-pressure vapour fraction and liquid fraction is then cooled, expanded and circulated through a first heat exchanger (5). During the vapour fraction's cooling and partial condensation stage, the vapour fraction obtained from the separation of the condensed mixture is cooled by passing it through a second heat exchanger (18) with the coolant. The condensed mixture is separated in a first separator (14). The vapour fraction from it is condensed in the second heat exchanger, and then passed through a second separator (15) to produce a vapour and a liquid fraction. The vapour fraction is sent to the final compression stage, and the liquid fraction to the first heat exchanger.
摘要:
In an integral incorporated cascade-type process the cooling mixture from the penultimate stage (1B) of the single cycle compressor (1) is fed into a distillation apparatus (5), the overhead vapour of which is cooled (at 24) to a temperature considerably less than ambient temperature. The vapour is then separated into two phases (at 6C); the vapour phase supplies the last stage (1C) of the compressor, and the liquid phase provides a cooling fluid for the hot part (8) of the thermal exchange line (7).
摘要:
Compact helium gas-refrigerating and liquefying apparatus with excellent properties and high reliability is provided. The apparatus comprises; a neon gas-refrigerating and liquefying circuit system which precools helium gas and composed of a turbo type compressor, heat exchangers, turbo type expansion machines and a Joule-Thomson valve; and a helium gas-refrigerating and liquefying circuit system which receves the precooled helium gas and composed of a turbo type compressor, heat exchangers, an expansion turbine and a Joule-Thomson valve; the former circuit system being constructed to associate with the latter circuit system so as to further cool the precooled helium gas in the latter circuit system by heat exchange therewith.
摘要:
An integral compressor-expander assembly, including a cryogenic expander positioned in an overhung configuration on a central shaft; a multi-stage centrifugal compressor supported on the central shaft between at least two bearings; and a device coupled to the central shaft and configured to either supply rotational power to the central shaft or generate power from rotation of the central shaft, depending upon a current operational mode of the multi-stage compressor.