EP0711968A2 - Process for the intermediate storage of refrigerant - Google Patents
Process for the intermediate storage of refrigerant Download PDFInfo
- Publication number
- EP0711968A2 EP0711968A2 EP95117285A EP95117285A EP0711968A2 EP 0711968 A2 EP0711968 A2 EP 0711968A2 EP 95117285 A EP95117285 A EP 95117285A EP 95117285 A EP95117285 A EP 95117285A EP 0711968 A2 EP0711968 A2 EP 0711968A2
- Authority
- EP
- European Patent Office
- Prior art keywords
- refrigerant
- pressure
- components
- coolant
- pressure storage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 238000000034 method Methods 0.000 title claims abstract description 13
- 239000003507 refrigerant Substances 0.000 title claims description 49
- 238000012432 intermediate storage Methods 0.000 title abstract 2
- 238000003860 storage Methods 0.000 claims abstract description 26
- 239000007788 liquid Substances 0.000 claims description 9
- 230000005484 gravity Effects 0.000 claims description 2
- 238000001816 cooling Methods 0.000 abstract description 3
- 239000002826 coolant Substances 0.000 abstract 5
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 10
- 239000000203 mixture Substances 0.000 description 5
- 238000005057 refrigeration Methods 0.000 description 5
- 239000003345 natural gas Substances 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 229930195733 hydrocarbon Natural products 0.000 description 2
- 150000002430 hydrocarbons Chemical class 0.000 description 2
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000005429 filling process Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 238000009827 uniform distribution Methods 0.000 description 1
- 238000010792 warming Methods 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/0002—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the fluid to be liquefied
- F25J1/0022—Hydrocarbons, e.g. natural gas
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/003—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the kind of cold generation within the liquefaction unit for compensating heat leaks and liquid production
- F25J1/0047—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the kind of cold generation within the liquefaction unit for compensating heat leaks and liquid production using an "external" refrigerant stream in a closed vapor compression cycle
- F25J1/0052—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the kind of cold generation within the liquefaction unit for compensating heat leaks and liquid production using an "external" refrigerant stream in a closed vapor compression cycle by vaporising a liquid refrigerant stream
- F25J1/0055—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures characterised by the kind of cold generation within the liquefaction unit for compensating heat leaks and liquid production using an "external" refrigerant stream in a closed vapor compression cycle by vaporising a liquid refrigerant stream originating from an incorporated cascade
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/02—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process
- F25J1/0211—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process using a multi-component refrigerant [MCR] fluid in a closed vapor compression cycle
- F25J1/0212—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process using a multi-component refrigerant [MCR] fluid in a closed vapor compression cycle as a single flow MCR cycle
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/02—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process
- F25J1/0243—Start-up or control of the process; Details of the apparatus used; Details of the refrigerant compression system used
- F25J1/0244—Operation; Control and regulation; Instrumentation
- F25J1/0245—Different modes, i.e. 'runs', of operation; Process control
- F25J1/0247—Different modes, i.e. 'runs', of operation; Process control start-up of the process
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/02—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process
- F25J1/0243—Start-up or control of the process; Details of the apparatus used; Details of the refrigerant compression system used
- F25J1/0244—Operation; Control and regulation; Instrumentation
- F25J1/0245—Different modes, i.e. 'runs', of operation; Process control
- F25J1/0248—Stopping of the process, e.g. defrosting or deriming, maintenance; Back-up mode or systems
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/02—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process
- F25J1/0243—Start-up or control of the process; Details of the apparatus used; Details of the refrigerant compression system used
- F25J1/0244—Operation; Control and regulation; Instrumentation
- F25J1/0245—Different modes, i.e. 'runs', of operation; Process control
- F25J1/0249—Controlling refrigerant inventory, i.e. composition or quantity
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J1/00—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
- F25J1/02—Processes or apparatus for liquefying or solidifying gases or gaseous mixtures requiring the use of refrigeration, e.g. of helium or hydrogen ; Details and kind of the refrigeration system used; Integration with other units or processes; Controlling aspects of the process
- F25J1/0243—Start-up or control of the process; Details of the apparatus used; Details of the refrigerant compression system used
- F25J1/0257—Construction and layout of liquefaction equipments, e.g. valves, machines
- F25J1/0262—Details of the cold heat exchange system
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J2245/00—Processes or apparatus involving steps for recycling of process streams
- F25J2245/02—Recycle of a stream in general, e.g. a by-pass stream
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J2290/00—Other details not covered by groups F25J2200/00 - F25J2280/00
- F25J2290/32—Details on header or distribution passages of heat exchangers, e.g. of reboiler-condenser or plate heat exchangers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
- F25J2290/00—Other details not covered by groups F25J2200/00 - F25J2280/00
- F25J2290/62—Details of storing a fluid in a tank
Definitions
- the invention relates to a method for temporarily storing the refrigerant of a refrigerant circuit, in which the refrigerant is compressed, subcooled and at least partially liquefied, expanded in a cold-performing manner and heated and evaporated in heat exchange with the process stream to be cooled.
- Refrigerant circuits are used in a variety of processes; the liquefaction of pressurized natural gas may be mentioned here as an example. If a system in which the refrigerant circuit is integrated has to be shut down for a longer period due to maintenance work or a malfunction, the refrigerant used within the refrigerant circuit must be temporarily stored due to high procurement costs or due to environmental considerations during the period of the system shutdown. Since the refrigerant circuit is no longer operated when the system is at a standstill, the refrigerant warms up to ambient temperature over time. This means that previously cold and liquid refrigerant can assume a very high pressure due to the warming up to ambient temperature and because of the limited volume available.
- the aim of the present invention is to provide an inexpensive method for temporarily storing the refrigerant of a refrigerant circuit in the event of a system shutdown.
- the circuit shown in the figure is a refrigeration circuit as it belongs to the prior art.
- a refrigerant for such a refrigeration cycle for example, mixtures of C2 to C3 hydrocarbons or mixtures of nitrogen, methane and C2 and C5 hydrocarbons can be used.
- the refrigerant or refrigerant mixture returned from the cold part of the system is fed via line 1 to a one- or multi-stage, in the case shown, a two-stage compression V. After each compressor stage, the refrigerant is cooled, for example against air, in a heat exchanger or cooler W.
- the pressure on the suction side of the first compressor is approx. 4 to 6 bar
- the pressure on the pressure side of the second compressor is approx. 40 to 60 bar.
- the compressed refrigerant is then fed into the separator D1 via line 2.
- the shut-off valve b is closed in normal operation, while the shut-off valves a, c and d are open.
- the light components of the refrigerant are discharged via line 5 with the valve d open and passed through the heat exchangers E1, E2 and E3 to the expansion valve e.
- These are now relaxed in the expansion valve e using the Joule-Thompson effect, and then passed through line 6 in counterflow to the natural gas stream to be cooled in line 100 and the high-pressure refrigerant in line 5 through the heat exchangers E3 and E2.
- the refrigerant expanded in the valve e serves to provide the peak cooling required for the liquefaction and subcooling of the natural gas flow conducted in line 100 through the heat exchangers E2 and E3.
- the heavy components of the refrigerant accumulating in the separator D1 at the sump are discharged via line 3 with the valve c open, cooled in the heat exchanger E1 and then expanded via line 4 and expansion valve f into the separator D2, after the refrigerant components from line 6 have been previously mixed.
- the separator D2 is used to form a homogeneous two-phase mixture, which supplies the cold necessary in the heat exchanger E1 to pre-cool the natural gas flow.
- the light refrigerant components are drawn off at the head of the separator D2 by means of line 7, while the heavy refrigerant components are drawn off at the bottom of the separator D2 via line 10.
- the line 10 opens into the line 7 immediately at the entry into the heat exchanger E1, so that a uniform distribution of the two-phase mixture is achieved at the entry of the heat exchanger E1.
- a branch line 8 with a shut-off valve a connects a storage tank S2 to line 7. This storage tank S2 is used for Temporary storage of gaseous refrigerant.
- the remaining lines and valves shown are required for the shutdown and restart procedure in the event of a plant shutdown.
- valve c is slowly closed. This ensures that all heavy refrigerant components of the refrigerant circuit, which condense according to the conditions of the heat exchanger or cooler W at a pressure of 40 to 60 bar, are stored in the separator D1. If this has happened, the bypass valve b in the line 2 'is opened and then the valves a and d are closed. While the compressor V continues to run, the high-pressure storage tank S1 is cooled by means of a small partial flow which, when the valve k is open, is drawn off from the bottom of the separator D2 by means of line 9 and is led via the collecting line 14 into the high-pressure storage tank S1.
- the resulting gaseous fraction within the high-pressure storage tank S1 is returned to the separator D2 for pressure equalization when the valve o is open via the lines 15 and 17.
- the liquid drain valves k and m are opened so that all the liquid components of the refrigerant stored on the low pressure side of the cold box can reach the high pressure storage container S1 via the lines 12, 13 and 14.
- the compressor V continues in part-load operation with the bypass valve b open in order to liquefy as much light components of the refrigerant as possible so that they can be filled into the high-pressure storage tank S1.
- the liquid components reach the high-pressure storage tank S1 using gravity.
- the compressor V is switched off, whereby a compensation pressure of approx. 6 to 8 bar is established within the refrigerant circuit after some time.
- the expansion valves e and f are then opened, as a result of which the liquid present on the high-pressure side of the refrigerant circuit is also filled into the high-pressure storage tank S1.
- the drain valve o is closed.
- the valve p is closed during the filling process of the high-pressure storage tank S1 described.
- the cold box warms up slowly to ambient temperature, but since only gas is stored in it, the pressure rises only insignificantly up to the standstill pressure.
- the high-pressure storage tank S1 Since the high-pressure storage tank S1 slowly warms up to ambient temperature, it is necessary to design it for this pressure. In conventional refrigeration circuits, the high-pressure storage tank S1 is designed for one Sufficient pressure from 100 to 150 bar.
- the storage container S2, which may be dispensed with, serves to hold gas under pressure during the standstill phase.
Abstract
Description
Die Erfindung betrifft ein Verfahren zum Zwischenspeichern des Kältemittels eines Kältemittelkreislaufes, in dem das Kältemittel komprimiert, unterkühlt und zumindest teilweise verflüssigt, kälteleistend entspannt und im Wärmetausch mit dem abzukühlenden Prozeßstrom angewärmt und verdampft wird.The invention relates to a method for temporarily storing the refrigerant of a refrigerant circuit, in which the refrigerant is compressed, subcooled and at least partially liquefied, expanded in a cold-performing manner and heated and evaporated in heat exchange with the process stream to be cooled.
Kältemittelkreisläufe kommen bei einer Vielzahl von Prozessen zur Anwendung; beispielhaft sei hier die Verflüssigung von unter Druck stehendem Erdgas genannt. Muß eine Anlage, in die der Kältemittelkreislauf eingebunden ist, aufgrund von Wartungsarbeiten oder einer Störung für einen längeren Zeitraum stillgelegt werden, muß das innerhalb des Kältemittelkreislaufes verwendete Kältemittel aufgrund hoher Beschaffungskosten oder aus Umweltschutzüberlegungen während des Zeitraumes des Anlagenstillstandes zwischengespeichert werden. Da bei einem Anlagenstillstand auch der Kältemittelkreislauf nicht weiter betrieben wird, kommt es mit der Zeit zu einer Anwärmung des Kältemittels auf Umgebungstemperatur. Dies bedeutet, daß zuvor kaltes und flüssiges Kältemittel aufgrund der Anwärmung auf Umgebungstemperatur und aufgrund des nur begrenzt zur Verfügung stehenden Volumens einen sehr hohen Druck annehmen kann. Aus diesen Gründen ist es unumgänglich, daß entweder Speicherbehälter für das auf Umgebungsdruck angewärmte Kältemittel vorgesehen sind oder aber der gesamte Kältemittelkreislauf für die Erwärmung des Kältemittels auf Umgebungstemperatur und die dabei entstehenden Drücke ausgelegt ist. Insbesondere die zweite Alternative würde den Kältemittelkreislauf jedoch erheblich verteuern.Refrigerant circuits are used in a variety of processes; the liquefaction of pressurized natural gas may be mentioned here as an example. If a system in which the refrigerant circuit is integrated has to be shut down for a longer period due to maintenance work or a malfunction, the refrigerant used within the refrigerant circuit must be temporarily stored due to high procurement costs or due to environmental considerations during the period of the system shutdown. Since the refrigerant circuit is no longer operated when the system is at a standstill, the refrigerant warms up to ambient temperature over time. This means that previously cold and liquid refrigerant can assume a very high pressure due to the warming up to ambient temperature and because of the limited volume available. For these reasons, it is inevitable that either storage tanks are provided for the refrigerant warmed to ambient pressure or that the entire refrigerant circuit is designed for heating the refrigerant to ambient temperature and the pressures that arise. However, the second alternative in particular would make the refrigerant circuit considerably more expensive.
Ziel der vorliegenden Erfindung ist es, ein kostengünstiges Verfahren zum Zwischenspeichern des Kältemittels eines Kältemittelkreislaufes im Falle eines Anlagenstillstandes anzugeben.The aim of the present invention is to provide an inexpensive method for temporarily storing the refrigerant of a refrigerant circuit in the event of a system shutdown.
Dies wird erfindungsgemäß dadurch erreicht, daß die auf der Hochdruckseite des Kältemittelkreislaufes unter Umgebungsbedingungen kondensierenden Kältemittelkomponenten in einen Abscheider D1 geleitet und in diesem zwischengespeichert werden und die innerhalb des kalten Bereichs des Kältemittelkreislaufes befindlichen flüssigen Kältemittelkomponenten in einen Hochdruckspeicherbehälter S1 geleitet und in diesem zwischengespeichert werden.This is achieved according to the invention in that the refrigerant components condensing on the high-pressure side of the refrigerant circuit under ambient conditions are passed into a separator D1 and temporarily stored therein, and the liquid refrigerant components located within the cold region of the refrigerant circuit are directed into a high-pressure storage tank S1 and are intermediately stored therein.
Die Erfindung sowie weitere Ausgestaltungen davon seien anhand der Figur näher erläutert.The invention and further refinements thereof are explained in more detail with reference to the figure.
Bei dem in der Figur dargestellten Kreislauf handelt es sich um einen Kältekreislauf, wie er zum Stand der Technik zählt. Als Kältemittel für einen derartigen Kältekreislauf können z.B. Gemische aus C₂- bis C₃-Kohlenwasserstoffen oder Gemische aus Stickstoff, Methan sowie C₂- und C₅-Kohlenwasserstoffen verwendet werden. Das aus dem kalten Teil der Anlage zurückgeführte Kältemittel bzw. Kältemittelgemisch wird mittels Leitung 1 einer ein- oder mehrstufigen, im gezeigten Fall einer zweistufigen Verdichtung V zugeführt. Nach jeder Verdichterstufe erfolgt eine Abkühlung des Kältemittels, z.B. gegen Luft, in einem Wärmetauscher bzw. Kühler W. Der Druck auf der Saugseite des ersten Verdichters liegt hierbei bei ca. 4 bis 6 bar, der Druck auf der Druckseite des zweiten Verdichters bei ca. 40 bis 60 bar. Das verdichtete Kältemittel wird anschließend über Leitung 2 in den Abscheider D1 gegeben. Das Absperrventil b ist im Normalbetrieb geschlossen, während die Absperrventile a, c und d geöffnet sind. Am Kopf des Abscheiders D1 werden über Leitung 5 bei geöffnetem Ventil d die leichten Komponenten des Kältemittels abgeführt und durch die Wärmetauscher E1, E2 und E3 zu dem Entspannungsventil e geleitet. Dabei kommt es zu einer Verflüssigung der Kältemittelkomponenten. Diese werden nun im Entspannungsventil e unter Ausnutzung des Joule-Thompson-Effekts kälteleistend entspannt und anschließend mittels Leitung 6 im Gegenstrom zu dem abzukühlenden Erdgasstrom in Leitung 100 und dem Hochdruckkältemittel in Leitung 5 durch die Wärmetauscher E3 und E2 geführt. Das im Ventil e entspannte Kältemittel dient zur Bereitstellung der für die Verflüssigung und Unterkühlung des in Leitung 100 durch die Wärmetauscher E2 und E3 geführten Erdgasstromes benötigten Spitzenkälte. Die im Abscheider D1 am Sumpf anfallenden schweren Komponenten des Kältemittels werden über Leitung 3 bei geöffnetem Ventil c abgeführt, im Wärmetauscher E1 abgekühlt und anschließend über Leitung 4 und Entspannungsventil f in den Abscheider D2, nach vorheriger Beimischung der Kältemittelkomponenten aus Leitung 6, entspannt. Der Abscheider D2 dient zur Bildung eines homogenen Zwei-Phasengemisches, welches die im Wärmetauscher E1 notwendige Kälte zur Vorkühlung des Erdgasstromes liefert. Dazu werden am Kopf des Abscheiders D2 mittels Leitung 7 die leichten Kältemittelkomponenten abgezogen, während am Sumpf des Abscheiders D2 über Leitung 10 die schweren Kältemittelkomponenten abgezogen werden. Unmittelbar am Eintritt in den Wärmetauscher E1 mündet die Leitung 10 in die Leitung 7, sodaß eine Gleichverteilung des Zwei-Phasengemisches am Eintritt des Wärmetauschers E1 erreicht wird. Eine Stichleitung 8 mit einem Absperrventil a verbindet einen Speicherbehälter S2 mit der Leitung 7. Dieser Speicherbehälter S2 dient zum Zwischenspeichern von gasförmigem Kältemittel. Die restlichen dargestellten Leitungen und Ventile werden im Falle eines Anlagenstillstandes für die Abfahr- und Wiederanfahrprozedur benötigt.The circuit shown in the figure is a refrigeration circuit as it belongs to the prior art. As a refrigerant for such a refrigeration cycle, for example, mixtures of C₂ to C₃ hydrocarbons or mixtures of nitrogen, methane and C₂ and C₅ hydrocarbons can be used. The refrigerant or refrigerant mixture returned from the cold part of the system is fed via line 1 to a one- or multi-stage, in the case shown, a two-stage compression V. After each compressor stage, the refrigerant is cooled, for example against air, in a heat exchanger or cooler W. The pressure on the suction side of the first compressor is approx. 4 to 6 bar, the pressure on the pressure side of the second compressor is approx. 40 to 60 bar. The compressed refrigerant is then fed into the separator D1 via line 2. The shut-off valve b is closed in normal operation, while the shut-off valves a, c and d are open. At the head of the separator D1, the light components of the refrigerant are discharged via line 5 with the valve d open and passed through the heat exchangers E1, E2 and E3 to the expansion valve e. This causes the refrigerant components to liquefy. These are now relaxed in the expansion valve e using the Joule-Thompson effect, and then passed through line 6 in counterflow to the natural gas stream to be cooled in
Es sei zunächst die Abfahrprozedur beschrieben. Zu Beginn wird das Ventil c langsam geschlossen. Dadurch wird erreicht, daß alle schweren Kältemittelkomponenten des Kältemittelkreislaufes, die entsprechend den Bedingungen des Wärmetauschers bzw. Kühlers W bei einem Druck von 40 bis 60 bar kondensieren, im Abscheider D1 gespeichert werden. Ist dies geschehen, so wird das Bypassventil b in der Leitung 2' geöffnet und anschließend werden die Ventile a und d geschlossen. Während der Verdichter V weiterläuft, wird der Hochdruckspeicherbehälter S1 mittels eines kleinen Teilstromes, der bei geöffnetem Ventil k aus dem Sumpf des Abscheiders D2 mittels Leitung 9 abgezogen und über die Sammelleitung 14 in den Hochdruckspeicherbehälter S1 geführt wird, abgekühlt. Die dabei innerhalb des Hochdruckspeicherbehälters S1 anfallende gasförmige Fraktion wird bei geöffnetem Ventil o über die Leitungen 15 und 17 dem Abscheider D2 zum Druckausgleich zurückgeführt. Nun werden die Flüssigkeitsablaßventile k und m geöffnet, sodaß alle innerhalb der Cold-Box auf der Niederdruckseite gespeicherten Flüssiganteile des Kältemittels über die Leitungen 12, 13 und 14 in den Hochdruckspeicherbehälter S1 gelangen können. Während des Befüllens des Hochdruckspeicherbehälters S1 fährt der Verdichter V in Teillastbetrieb mit geöffnetem Bypassventil b weiter, um so viel wie möglich leichte Bestandteile des Kältemittels zu verflüssigen, damit diese in den Hochdruckspeicherbehälter S1 abgefüllt werden können. Gemäß einer Ausgestaltung des erfindungsgemäßen Verfahrens gelangen die Flüssiganteile unter Ausnutzung der Schwerkraft in den Hochdruckspeicherbehälter S1. Nun wird der Verdichter V abgeschaltet, wodurch sich nach einiger Zeit innerhalb des Kältemittelkreislaufes ein Ausgleichsdruck von ca. 6 bis 8 bar einstellt. Sodann werden die Entspannungsventile e und f geöffnet, wodurch die auf der Hochdruckseite des Kältemittelkreislaufes vorliegende Flüssigkeit ebenfalls in den Hochdruckspeicherbehälter S1 eingefüllt wird. Ist die Abfüllung, die über den Flüssigkeitsstand im Hochdruckspeicherbehälter S1 kontrolliert werden kann, abgeschlossen, so wird das Ablaßventil o geschlossen. Das Ventil p ist während des beschriebenen Befüllvorgangs des Hochdruckspeicherbehälters S1 geschlossen. Die Cold-Box wärmt sich nun zwar langsam auf Umgebungstemperatur an, da jedoch nur noch Gas in ihr gespeichert ist, steigt der Druck bis zum Stillstandsdruck nurmehr unerheblich. Da sich auch der Hochdruckspeicherbehälter S1 langsam auf Umgebungstemperatur anwärmt, ist es notwendig, ihn für diesen Druck auszulegen. Bei herkömmlichen Kältekreisläufen ist eine Auslegung des Hochdruckspeicherbehälters S1 auf einen Druck von 100 bis 150 bar ausreichend. Der Speicherbehälter S2, auf den gegebenenfalls verzichtet werden kann, dient zur Aufnahme von unter Druck stehendem Gas während der Stillstandsphase.The shutdown procedure is first described. At the beginning, valve c is slowly closed. This ensures that all heavy refrigerant components of the refrigerant circuit, which condense according to the conditions of the heat exchanger or cooler W at a pressure of 40 to 60 bar, are stored in the separator D1. If this has happened, the bypass valve b in the line 2 'is opened and then the valves a and d are closed. While the compressor V continues to run, the high-pressure storage tank S1 is cooled by means of a small partial flow which, when the valve k is open, is drawn off from the bottom of the separator D2 by means of
Im folgenden sei die Wiederanfahrprozedur des Kältekreislaufes beschrieben. Bei geöffnetem Bypassventil b wird der Kreislaufdichter V unter dem Stillstandsdruck angefahren. Nun wird das Ablaßventil p am Hochdruckspeicherbehälter S1 langsam geöffnet und dadurch der Inhalt des Hochdruckspeicherbehälters S1 langsam in den Abscheider D2 eingespeist. Nachdem der Druck im Hochdruckspeicherbehälter S1 auf den Saugdruck gefallen und kein Flüssigkeitsstand im Hochdruckspeicherbehälter S1 mehr festzustellen ist, wird das Ventil p wieder geschlossen, sodaß der Hochdruckspeicherbehälter S1 hermetisch abgesperrt ist. Nach Schließen der Ventile b, e und f sowie nach dem Öffnen der Ventile a, c und d, erreicht der Kältekreislauf innerhalb kurzer Zeit seinen Betriebszustand.The restart procedure of the refrigeration cycle is described below. When the bypass valve b is open, the circuit seal V is started under the standstill pressure. Now the drain valve p on the high-pressure storage tank S1 is slowly opened and the content of the high-pressure storage tank S1 is thereby slowly fed into the separator D2. After the pressure in the high-pressure storage container S1 has dropped to the suction pressure and there is no longer any liquid level in the high-pressure storage container S1, the valve p is closed again, so that the high-pressure storage container S1 is hermetically sealed. After closing valves b, e and f and after opening valves a, c and d, the refrigeration cycle reaches its operating state within a short time.
Claims (2)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE4440405A DE4440405C1 (en) | 1994-11-11 | 1994-11-11 | Method for temporarily storing a refrigerant |
| DE4440405 | 1994-11-11 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| EP0711968A2 true EP0711968A2 (en) | 1996-05-15 |
| EP0711968A3 EP0711968A3 (en) | 1997-02-05 |
Family
ID=6533119
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP95117285A Withdrawn EP0711968A3 (en) | 1994-11-11 | 1995-11-02 | Process for the intermediate storage of refrigerant |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US5636529A (en) |
| EP (1) | EP0711968A3 (en) |
| AR (1) | AR000099A1 (en) |
| DE (1) | DE4440405C1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19716415C1 (en) * | 1997-04-18 | 1998-10-22 | Linde Ag | Process for liquefying a hydrocarbon-rich stream |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE10206388A1 (en) * | 2002-02-15 | 2003-08-28 | Linde Ag | Process for liquefying a hydrocarbon-rich stream |
| US7024883B2 (en) * | 2003-12-19 | 2006-04-11 | Carrier Corporation | Vapor compression systems using an accumulator to prevent over-pressurization |
| US7134296B2 (en) * | 2004-10-13 | 2006-11-14 | Praxair Technology, Inc. | Method for providing cooling for gas liquefaction |
| DE102005010051A1 (en) * | 2005-03-04 | 2006-09-07 | Linde Ag | Process for vaporizing a hydrocarbon-rich stream |
| US7575649B2 (en) * | 2006-06-21 | 2009-08-18 | Jeffrey Arippol | Label structure and label structure obtaining method |
| NO328493B1 (en) * | 2007-12-06 | 2010-03-01 | Kanfa Aragon As | System and method for regulating the cooling process |
| GB2583873B (en) * | 2018-01-12 | 2022-07-13 | Nuovo Pignone Tecnologie Srl | A thermodynamic system containing a fluid, and method for reducing pressure therein |
| US11326834B2 (en) * | 2018-08-14 | 2022-05-10 | Exxonmobil Upstream Research Company | Conserving mixed refrigerant in natural gas liquefaction facilities |
| IT202000020479A1 (en) * | 2020-08-26 | 2022-02-26 | Nuovo Pignone Tecnologie Srl | A SYSTEM AND METHOD FOR REDUCING SETTLE PRESSURE USING A BOOSTER COMPRESSOR |
| WO2022042879A1 (en) * | 2020-08-26 | 2022-03-03 | Nuovo Pignone Tecnologie - S.R.L. | A system and a method for reducing settle-out pressure using an auxiliary compressor |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2524179A1 (en) * | 1974-05-31 | 1976-01-08 | Technip Cie | PROCESS AND SYSTEM FOR COOLING A GAS MIXTURE |
| DE2754892A1 (en) * | 1977-12-09 | 1979-06-13 | Linde Ag | Liquefaction and storage of natural gas - using successive compression and cooling stages while ensuring that limit of solubility of higher boiling components is not exceeded |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3331214A (en) * | 1965-03-22 | 1967-07-18 | Conch Int Methane Ltd | Method for liquefying and storing natural gas and controlling the b.t.u. content |
| DE2820212A1 (en) * | 1978-05-09 | 1979-11-22 | Linde Ag | METHOD FOR LIQUIDATING NATURAL GAS |
| US4901533A (en) * | 1986-03-21 | 1990-02-20 | Linde Aktiengesellschaft | Process and apparatus for the liquefaction of a natural gas stream utilizing a single mixed refrigerant |
| US5359856A (en) * | 1993-10-07 | 1994-11-01 | Liquid Carbonic Corporation | Process for purifying liquid natural gas |
-
1994
- 1994-11-11 DE DE4440405A patent/DE4440405C1/en not_active Expired - Fee Related
-
1995
- 1995-11-02 EP EP95117285A patent/EP0711968A3/en not_active Withdrawn
- 1995-11-09 US US08/556,196 patent/US5636529A/en not_active Expired - Fee Related
- 1995-11-09 AR AR33417495A patent/AR000099A1/en unknown
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2524179A1 (en) * | 1974-05-31 | 1976-01-08 | Technip Cie | PROCESS AND SYSTEM FOR COOLING A GAS MIXTURE |
| DE2754892A1 (en) * | 1977-12-09 | 1979-06-13 | Linde Ag | Liquefaction and storage of natural gas - using successive compression and cooling stages while ensuring that limit of solubility of higher boiling components is not exceeded |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE19716415C1 (en) * | 1997-04-18 | 1998-10-22 | Linde Ag | Process for liquefying a hydrocarbon-rich stream |
Also Published As
| Publication number | Publication date |
|---|---|
| DE4440405C1 (en) | 1996-05-23 |
| US5636529A (en) | 1997-06-10 |
| AR000099A1 (en) | 1997-05-21 |
| EP0711968A3 (en) | 1997-02-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP2244040B1 (en) | Flashgas removal from a receiver in a refrigeration circuit | |
| EP0975923B1 (en) | Method for liquefying a stream rich in hydrocarbons | |
| DE102010044646A1 (en) | Process for separating nitrogen and hydrogen from natural gas | |
| WO2006094675A1 (en) | Method for liquefaction of a stream rich in hydrocarbons | |
| WO2010091805A2 (en) | Method for removing nitrogen | |
| DE102010044869A1 (en) | Liquefied Natural gas | |
| DE4440405C1 (en) | Method for temporarily storing a refrigerant | |
| WO2010121752A2 (en) | Method for liquefying a hydrocarbon-rich fraction | |
| WO2008022689A2 (en) | Method for the liquefaction of a hydrocarbon-rich flow | |
| DE102011109234A1 (en) | Liquefaction of methane-rich gas e.g. natural gas, involves cooling methane-rich gas, liquefying, separating low boiling component, compressing, cooling and storing | |
| DE10226596A1 (en) | Process for liquefying a hydrocarbon-rich stream with simultaneous recovery of a C3 + -rich fraction with high yield | |
| DE19612173C1 (en) | Procedure for liquefaction of hydrocarbon rich process flow, especially natural gas | |
| DE10119761A1 (en) | Liquefaction of natural gas employs compressor driving cooling flow by burning proportion of natural gas liquefied | |
| DE102006039616B3 (en) | Method and device for storing fuel gas, in particular natural gas | |
| DE102006021620B4 (en) | Pretreatment of a liquefied natural gas stream | |
| DE4440406C1 (en) | Process for liquefying a pressurized hydrocarbon-rich fraction | |
| WO2003074955A1 (en) | Method for liquefying a hydrocarbon-rich flow | |
| DE10111428A1 (en) | Method and device for separating a gas mixture with emergency operation | |
| EP1913319A2 (en) | Method and arrangement for liquefying a stream rich in hydrocarbons | |
| WO2017054929A1 (en) | Method for liquefying a hydrocarbon-rich fraction | |
| DE4309137A1 (en) | Cold process working cycle for refrigerator | |
| DE2009401A1 (en) | Process for liquefying low-boiling gases | |
| WO2010094396A2 (en) | Method for removing nitrogen | |
| DE2049181A1 (en) | Refrigeration cycle - with expansion of low boiling fraction of mixtu through turbine | |
| EP1001236B1 (en) | Process for producing ultra pure nitrogen |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
| AK | Designated contracting states |
Kind code of ref document: A2 Designated state(s): BE CH DE GB LI NL |
|
| PUAL | Search report despatched |
Free format text: ORIGINAL CODE: 0009013 |
|
| AK | Designated contracting states |
Kind code of ref document: A3 Designated state(s): BE CH DE GB LI NL |
|
| 17P | Request for examination filed |
Effective date: 19970117 |
|
| 17Q | First examination report despatched |
Effective date: 19990125 |
|
| STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN |
|
| 18D | Application deemed to be withdrawn |
Effective date: 19990611 |