EP0098446B1 - Heat exchanger - Google Patents

Heat exchanger Download PDF

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Publication number
EP0098446B1
EP0098446B1 EP83106023A EP83106023A EP0098446B1 EP 0098446 B1 EP0098446 B1 EP 0098446B1 EP 83106023 A EP83106023 A EP 83106023A EP 83106023 A EP83106023 A EP 83106023A EP 0098446 B1 EP0098446 B1 EP 0098446B1
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EP
European Patent Office
Prior art keywords
heating
heat exchanger
enamelled
tube
container
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.)
Expired
Application number
EP83106023A
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German (de)
French (fr)
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EP0098446A2 (en
EP0098446A3 (en
Inventor
Rudolf Dr. Schwab
Guenter Jeckel
Gerhard Hofmann
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BASF SE
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BASF SE
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Publication date
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Publication of EP0098446A2 publication Critical patent/EP0098446A2/en
Publication of EP0098446A3 publication Critical patent/EP0098446A3/en
Application granted granted Critical
Publication of EP0098446B1 publication Critical patent/EP0098446B1/en
Expired legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D1/00—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators
    • F28D1/02—Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, in which the other heat-exchange medium is a large body of fluid, e.g. domestic or motor car radiators with heat-exchange conduits immersed in the body of fluid
    • F28D1/0206—Heat exchangers immersed in a large body of liquid
    • F28D1/0213—Heat exchangers immersed in a large body of liquid for heating or cooling a liquid in a tank
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F19/00—Preventing the formation of deposits or corrosion, e.g. by using filters or scrapers
    • F28F19/02—Preventing the formation of deposits or corrosion, e.g. by using filters or scrapers by using coatings, e.g. vitreous or enamel coatings

Definitions

  • the invention relates to a heat exchanger consisting of a closed container and at least one heating plug inserted into the container, which is acted upon on the inside with a heating or cooling medium and is surrounded on the outside by the contents of the container.
  • a heat exchanger which consists of a closed container with at least one heating plug inserted into the container, which is acted upon on the inside with a heating or cooling medium and is surrounded on the outside by the contents of the container.
  • DE-PS 839 806 shows a star-shaped folded tube as an insert tube for heat exchangers.
  • the container is enamelled on the inside and that the heating plug is provided with hollow ribs and is also enamelled on the outside.
  • FIG. 1 shows in detail an externally enamelled heating plug 2 provided with hollow ribs 12 and the installation thereof in the bottom of the inside enamelled container 1.
  • the heating plug 2 provided with hollow ribs is welded to a displacer 3 of conventional design by means of the weld 4.
  • an insertion tube 5 is inserted up to close to the cover of the heating plug 2, which is connected to the displacer 3 in the usual way.
  • Displacement body 3 and heating plug 2 are after assembly, ie after the weld 4 has been applied, after the cover 7 has been welded on by means of the weld 8 and after the installation of the Insert tube 5 enamelled on the outside.
  • This assembled enamelled unit on the outside is installed via the base flange 9 of conventional design, by means of the seal 10 and clamp screws 11 distributed around the circumference of the base flange 9. If the cover 7 of the heating plug 2 is omitted, a second heating plug can be used to enlarge the heat exchange surface - as in FIG. 1 shown - be welded.
  • FIG. 3 shows the section through a heating plug with a cylindrical cross section and hollow ribs 12 arranged in a star shape.
  • FIG. 4 shows the section through a heating plug with hollow ribs arranged in parallel.
  • the advantages achieved with the heat exchanger according to the invention are, in particular, to produce heat exchange surfaces for chemical processes and similar fields of application in which extremely expensive materials such as titanium or zirconium can be dispensed with when aggressive media are being passed through.
  • These heat exchangers according to the invention can therefore be produced at comparable heat exchange surfaces - based on m 2 heat exchange surface - significantly more cost-effectively than, for example, tube bundle heat exchangers made of the above-mentioned materials or heat exchangers with cased double jacket tubes, in which the inner tubes consist of titanium or zirconium or of enamelled steel tubes.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)

Description

Die Erfindung betrifft einen Wärmetauscher, bestehend aus einem geschlossenen Behälter und mindestens einer in den Behälter eingesteckten Heizkerze, die innenseitig mit einem Heiz- oder Kühlmedium beaufschlagt und außenseitig von dem Behälterinhalt umgeben ist.The invention relates to a heat exchanger consisting of a closed container and at least one heating plug inserted into the container, which is acted upon on the inside with a heating or cooling medium and is surrounded on the outside by the contents of the container.

Bei chemischen Prozessen mit stark aggressiven Medien ist die Wahl der Werkstoffe für die Apparate, in denen die Prozesse ablaufen, von großer Wichtigkeit, insbesondere dann, wenn austenitische Stähle als Werkstoff aufgrund der Aggressivität der Medien ausscheiden. Während beispielsweise bei Rührbehältern häufig Apparate mit einer Innenemaillierung gewählt werden, ist dies - wie später detailliert geschildert - bei Wärmetauschern, die in Chemieanlagen und ähnlichen Arbeitsgebieten überwiegend als Rohrbündelwärmeaustauscher-ausgeführt sind und Temperaturschwankungen unterliegen, nicht möglich.In chemical processes with highly aggressive media, the choice of materials for the apparatus in which the processes run is of great importance, especially when austenitic steels are eliminated as a material due to the aggressiveness of the media. While, for example, apparatus with inner enamelling is often selected for stirred tanks, this is not possible - as will be described in detail later - with heat exchangers, which in chemical plants and similar work areas are predominantly designed as shell-and-tube heat exchangers and are subject to temperature fluctuations.

Es ist bekannt, in solchen Fällen Rohrbündelwärmeaustauscher einzusetzen, bei denen alle Bauteile, die in Berührung mit den aggressiven Medien gelangen, aus Werkstoffen wie Titan oder Zirkonium gefertigt werden. Eine andere Ausführungsform von Wärmetauschern besteht darin, eine Vielzahl von Doppelmantelrohren, bei denen die Innenrohre aus Werkstoffen wie Titan, Zirkonium oder innenseitig emaillierten Stahlrohren bestehen, hintereinander zu schalten. Bei beidenArten von Wärmetauschern befinden sich die aggressiven Medien in den Rohren und die Heiz- bzw. Kühlmedien um die Rohre. Beide Ausführungsformen - Rohrbündelwärmeaustauscher und hintereinander geschaltete Doppelrohre - sind aufgrund der oben erwähnten Werkstoffe extrem teuer. Daher wurde stets versucht emaillierte Rohrbündelwärmeaustausche.r, bei denen sich die aggressiven Medien ebenfalls in den Rohren befinden, herzustellen. Dies ist jedoch fertigungstechnisch nicht möglich, da es bei Temperaturschwankungen - die während der Emaillierung bzw. während des Prozeßablaufes auftreten- stets zu Emaillebruch kommt. Dies erklärt sich daraus, daß die Biegung der Rohrböden bei instationärem Aufheizen bzw. die Beulung der Rohrböden bei instationärem Abkühlen große axiale Zug- bzw. Druckkräfte in den Rohren verursachen, deren Einleitung in die Rohrböden bisher ohne Emaillebruch an den Einschweißungen der Rohre in die Rohrböden nicht gelungen ist. Der Versuch, jeweils ein Rohrende der innenseitig emaillierten Rohre in einem Rohrboden des Rohrbündelwärmeaustauschers axial verschiebbar einzubauen und abzudichten, war im Dauerversuch wegen chemischer, mechanischer, thermischer und sonstiger Einwirkungen stets erfolglos.It is known to use shell-and-tube heat exchangers in such cases in which all components which come into contact with the aggressive media are made from materials such as titanium or zirconium. Another embodiment of heat exchangers is to connect a large number of double-jacket tubes in which the inner tubes are made of materials such as titanium, zirconium or steel tubes enamelled on the inside. In both types of heat exchangers, the aggressive media are in the pipes and the heating or cooling media are around the pipes. Both embodiments - shell-and-tube heat exchangers and double pipes connected in series - are extremely expensive due to the materials mentioned above. Therefore, attempts have always been made to produce enamelled tube bundle heat exchangers, in which the aggressive media are also located in the tubes. However, this is not possible from a manufacturing point of view, since enamel breakage always occurs in the event of temperature fluctuations - which occur during enamelling or during the course of the process. This is explained by the fact that the deflection of the tubesheets at Transient heating, or the buckling of the tube sheets at unsteady cooling large axial train - and compressive forces cause the tubes, the introduction into the tube plates so far without enamel fracture at the Einschweißungen of the tubes into the tubesheets has not succeeded. The attempt to install and seal one tube end of the inside enamelled tubes in a tube plate of the tube bundle heat exchanger was always unsuccessful due to chemical, mechanical, thermal and other effects.

Aus den selben Gründen war auch ein Wärmetauscher mit Emaillierung zusammengebaut aus einzelnen Plattenelementen - wie in der DE-PS 1 054101 beschrieben - im Dauerbetrieb nicht einsetzbar.For the same reasons, a heat exchanger with enamelling assembled from individual plate elements - as described in DE-PS 1 054101 - could not be used in continuous operation.

Desweiteren ist gemäß der US-PS 2 376 373 ein Wärmetauscher bekannt, der aus einem geschlossenen Behälter mit mindestens einer in den Behälter eingesteckten Heizkerze besteht, die innenseitig mit einem Heiz- oder Kühlmedium beaufschlagt und außenseitig von dem Behälterinhalt umgeben ist. In derDE-PS 839 806 ist ein sternförmiges Faltenrohr als Einsatzrohr für Wärmetauscher aufgezeigt. Jedoch sind diese Apparateteile beim Einsatz won aggressiven Medien nicht verwendbar.Furthermore, according to US Pat. No. 2,376,373, a heat exchanger is known which consists of a closed container with at least one heating plug inserted into the container, which is acted upon on the inside with a heating or cooling medium and is surrounded on the outside by the contents of the container. DE-PS 839 806 shows a star-shaped folded tube as an insert tube for heat exchangers. However, these parts of the apparatus cannot be used when aggressive media are used.

Es stellte sich daher die Aufgabe, bei der Erwärmung oder Kühlung eines in einem Behälter lagernden, extrem aggressiven Medium, die Heizkerze nicht aus Titan oder Zirkonium - wie beispielsweise bei Rohrbündelwärmeeustauschern - herstellen zu müssen.It was therefore the task when heating or cooling an extremely aggressive medium stored in a container not to have to produce the heating plug from titanium or zirconium, as is the case, for example, with shell-and-tube heat exchangers.

Diese Aufgabe wird erfindungsgemäß dadurch gelöst, daß der Behälter innenseitig emailliert ist, und daß die Heizkerze mit Hohlrippen versehen sowie auf der Außenseite ebenfalls emailliert ist.This object is achieved in that the container is enamelled on the inside and that the heating plug is provided with hollow ribs and is also enamelled on the outside.

Ein Ausführungsbeispiel der Erfindung ist in der Zeichnung dargestellt und wird im folgenden näher beschrieben. Es zeigen:

  • Figur 1 einen Schnitt durch den erfindungsgemäßen Wärmetauscher,
  • Figur 2 einen Schnitt durch eine mit Hohlrippen versehene an der Außenseite emaillierten Heizkerze, eingesteckt in einen Flansch üblicher Bauform am Boden des innenseitig emaillierten Behälters,
  • Figur 3 und 4 Schnitt durch zwei Profilquerschnitte einer Heizkerze, ausgewählt aus der Vielzahl der Möglichkeiten von Profilquerschnitten von Heizkerzen.
An embodiment of the invention is shown in the drawing and will be described in more detail below. Show it:
  • FIG. 1 shows a section through the heat exchanger according to the invention,
  • FIG. 2 shows a section through a heating plug enamelled on the outside with hollow ribs, inserted into a flange of conventional design at the bottom of the inside enamelled container,
  • Figures 3 and 4 section through two profile cross sections of a heating plug, selected from the variety of possibilities of profile cross sections of heating plugs.

Gemäß Figur 1 ist in den Boden des innenseitig emaillierten Berhälters 1 eine mit Hohlrippen 12 versehene außenseitig emaillierte Heizkerze 2 - bestehend aus einer Einheit von zwei Einzelkerzen - eingesteckt, die innenseitig mit Sattdampf beaufschlagt ist, und außenseitig von dem Behälterinhalt umgeben ist. Figur 2 zeigt im Detail eine mit Hohlrippen 12 versehene außenseitig emaillierte Heizkerze 2 und den Einbau derselben in den Boden des innenseitig emaillierten Berhälters 1. An einen Verdrängerkörper 3 üblicher Bauform ist die mit Hohlrippen versehene Heizkerze 2 mittels der Schweißnaht 4 angeschweißt. In Verdrängerkörper 3 und Heizkerze ist ein Einsteckrohr 5 bis nahe an den Deckel der Heizkerze 2 eingeführt, das auf übliche Art mit dem Verdrängerkörper 3 verbunden ist. Über dieses Einsteckrohr 5 strömt Sattdampf in die Heizkerze, über den Stutzen 6 strömt das Kondensat ab. Verdrängerkörper 3 und Heizkerze 2 werden nach dem Zusammenbau, d.h. nach demAnlegen der Schweißnaht 4, nach dem Anschweißen des Deckels 7 mittels der Schweißnaht 8 und nach dem Einbau des Einsteckrohres 5 außenseitig emailliert. Der Einbau dieser zusammengefügten außenseitig emaillierten Einheit erfolgt über den Bodenflansch 9 üblicher Bauart, mittels der Dichtung 10 und am Umfang des Bodenflansches 9 verteilter Klammerschrauben 11. Beim Weglassen des Deckels 7 der Heizkerze 2 kann eine zweite Heizkerze zur Vergrößerung der Wärmetauschfläche - wie in Figur 1 dargestellt - angeschweißt werden. Die Hohlrippen 12 der einzelnen Heizkerzen können zur Verbesserung des Wärmeübergangs auch gegeneinander versetzt angeordnet werden. Figur 3 zeigt den Schnitt durch eine Heizkerze mit zylindrischem Querschnitt und sternförmig angeordneten Hohlrippen 12. Figur 4 zeigt den Schnitt durch eine Heizkerze mit parallel angeordneten Hohlrippen.According to FIG. 1, in the bottom of the container 1 enamelled on the inside, a heating candle 2 provided with hollow ribs 12 and on the outside enamelled - consisting of a unit of two individual candles - is inserted, which is charged with saturated steam on the inside and is surrounded on the outside by the contents of the container. FIG. 2 shows in detail an externally enamelled heating plug 2 provided with hollow ribs 12 and the installation thereof in the bottom of the inside enamelled container 1. The heating plug 2 provided with hollow ribs is welded to a displacer 3 of conventional design by means of the weld 4. In the displacer 3 and the heating plug, an insertion tube 5 is inserted up to close to the cover of the heating plug 2, which is connected to the displacer 3 in the usual way. Saturated steam flows into the heating plug via this plug-in tube 5, and the condensate flows out through the nozzle 6. Displacement body 3 and heating plug 2 are after assembly, ie after the weld 4 has been applied, after the cover 7 has been welded on by means of the weld 8 and after the installation of the Insert tube 5 enamelled on the outside. This assembled enamelled unit on the outside is installed via the base flange 9 of conventional design, by means of the seal 10 and clamp screws 11 distributed around the circumference of the base flange 9. If the cover 7 of the heating plug 2 is omitted, a second heating plug can be used to enlarge the heat exchange surface - as in FIG. 1 shown - be welded. The hollow fins 12 of the individual heating plugs can also be arranged offset from one another to improve the heat transfer. FIG. 3 shows the section through a heating plug with a cylindrical cross section and hollow ribs 12 arranged in a star shape. FIG. 4 shows the section through a heating plug with hollow ribs arranged in parallel.

Die mit dem erfindungsgemäßen Wärmetauscher erzielten Vorteile liegen insbesondere darin, Wärmetauschflächen für chemische Prozesse und ähnliche Anwendungsgebiete herzustellen, bei denen beim Durchsatz von aggressiven Medien auf extrem teure Werkstoffe wie Titan oder Zirkonium verzichtet werden kann. Diese erfindungsgemäßen Wärmetauscher sind daher bei vergleichbaren Wärmetauschflächen - bezogen auf m2 Wärmetauschfläche - deutlich kostengünstiger herzustellen als beispielsweise Röhrenbündelwärmeaustauscher aus den oben erwähnten Materialien oder Wärmetauschern mit hintereinander geschalteten Doppelmantelrohren, bei denen die Innenrohre aus Titan oder Zirkonium oder aus innenseitig emaillierten Stahlrohren bestehen.The advantages achieved with the heat exchanger according to the invention are, in particular, to produce heat exchange surfaces for chemical processes and similar fields of application in which extremely expensive materials such as titanium or zirconium can be dispensed with when aggressive media are being passed through. These heat exchangers according to the invention can therefore be produced at comparable heat exchange surfaces - based on m 2 heat exchange surface - significantly more cost-effectively than, for example, tube bundle heat exchangers made of the above-mentioned materials or heat exchangers with cased double jacket tubes, in which the inner tubes consist of titanium or zirconium or of enamelled steel tubes.

Claims (2)

1. A heat exchanger comprising a closed vessel and at least one immersion heater inserted in the vessel, the said heater being exposed on the inside to a heating or cooling medium and being surrounded on the outside by the vessel contents, wherein the vessel is enameled on the inside, and the immersion heater (2) is provided with hollow fins (12) and is enameled on the outside.
2. A heat exchanger as claimed in claim 1, wherein two or more immersion heaters (2) provided with hollow fins are combined to form a single unit.
EP83106023A 1982-07-01 1983-06-21 Heat exchanger Expired EP0098446B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3224529 1982-07-01
DE19823224529 DE3224529A1 (en) 1982-07-01 1982-07-01 HEAT EXCHANGER

Publications (3)

Publication Number Publication Date
EP0098446A2 EP0098446A2 (en) 1984-01-18
EP0098446A3 EP0098446A3 (en) 1985-01-30
EP0098446B1 true EP0098446B1 (en) 1987-05-20

Family

ID=6167297

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83106023A Expired EP0098446B1 (en) 1982-07-01 1983-06-21 Heat exchanger

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EP (1) EP0098446B1 (en)
JP (1) JPS5918393A (en)
DE (2) DE3224529A1 (en)

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE413505C (en) * 1923-10-16 1925-05-12 Razen Fa Heat exchange device
DE671630C (en) * 1931-09-25 1939-02-10 Gasaccumulator Svenska Ab Heating device, especially for water heating systems
US2376373A (en) * 1940-07-26 1945-05-22 Novadel Agene Corp Brew cooling
DE839806C (en) * 1949-08-02 1952-05-26 Otto H Dr-Ing E H Hartmann Star-shaped folded tube as an insert tube for heat exchangers
DE1129516B (en) * 1955-10-04 1962-05-17 Andre Huet Pipe heat exchanger, the heat exchange surface of which consists of many pairs of coaxially inserted pipes
US3268989A (en) * 1962-03-26 1966-08-30 Carrier Corp Method of assembling a ceramic lined water heater
GB1202936A (en) * 1967-09-25 1970-08-19 Murex Ltd The heating or cooling of corrosive liquids
SE7808367L (en) * 1978-08-03 1980-02-04 Ostbo John D B DEVICE EXCHANGER

Also Published As

Publication number Publication date
EP0098446A2 (en) 1984-01-18
EP0098446A3 (en) 1985-01-30
JPS5918393A (en) 1984-01-30
DE3224529A1 (en) 1984-01-05
DE3371690D1 (en) 1987-06-25

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