EP0219882B1 - Procédé et dispositif automatique de nettoyage d'un échangeur de chaleur pour fluides gazeux - Google Patents

Procédé et dispositif automatique de nettoyage d'un échangeur de chaleur pour fluides gazeux Download PDF

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Publication number
EP0219882B1
EP0219882B1 EP86114805A EP86114805A EP0219882B1 EP 0219882 B1 EP0219882 B1 EP 0219882B1 EP 86114805 A EP86114805 A EP 86114805A EP 86114805 A EP86114805 A EP 86114805A EP 0219882 B1 EP0219882 B1 EP 0219882B1
Authority
EP
European Patent Office
Prior art keywords
channels
injection
elastic members
additional
exchanger
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
EP86114805A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0219882A1 (fr
Inventor
Paul Barroyer
Eric Piat
Bernard Foucher
Léon Bouilliez
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Neu SA
Original Assignee
Neu SA
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Publication date
Application filed by Neu SA filed Critical Neu SA
Priority to AT86114805T priority Critical patent/ATE39284T1/de
Publication of EP0219882A1 publication Critical patent/EP0219882A1/fr
Application granted granted Critical
Publication of EP0219882B1 publication Critical patent/EP0219882B1/fr
Expired legal-status Critical Current

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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28GCLEANING OF INTERNAL OR EXTERNAL SURFACES OF HEAT-EXCHANGE OR HEAT-TRANSFER CONDUITS, e.g. WATER TUBES OR BOILERS
    • F28G7/00Cleaning by vibration or pressure waves
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28HEAT EXCHANGE IN GENERAL
    • F28GCLEANING OF INTERNAL OR EXTERNAL SURFACES OF HEAT-EXCHANGE OR HEAT-TRANSFER CONDUITS, e.g. WATER TUBES OR BOILERS
    • F28G1/00Non-rotary, e.g. reciprocated, appliances
    • F28G1/06Non-rotary, e.g. reciprocated, appliances having coiled wire tools, i.e. basket type

Definitions

  • the present invention relates to a method and an automatic device for periodically cleaning the surfaces of a heat exchanger intended to treat gaseous fluids flowing in vertical channels defined between said surfaces.
  • Another means of combating fouling and clogging is to provide cleaning of the inside of the tubes.
  • Devices for this purpose have been provided, in particular for tubular heat exchangers intended for the treatment of liquids.
  • FR-A-2 435 292 also suitable in the case of a heat exchanger for the treatment of liquids, uses a mechanical device to periodically stretch a helical spring whose function is to scrape the substances deposited along the walls, thus preventing their deterioration by local overheating. It is recommended to use a tight fit along the wall of the tube.
  • the present invention relates to an automatic method and device for periodic cleaning of the internal surfaces of a heat exchanger for gaseous fluids which makes it possible to obtain a vibration of elastic scraping elements placed inside the channels of the heat exchanger, and this by simple pneumatically actuated means, in order to solve the problems posed by the adaptation of known cleaning devices to heat exchangers intended to treat gaseous fluids.
  • the automatic method of periodic cleaning of the surfaces of a heat exchanger for gaseous fluids flowing in vertical channels between said surfaces makes use of elastic elements permanently arranged in said channels and capable of being vibrated to perform cleaning of said surfaces.
  • the elastic elements are vibrated successively for at least one group of channels of the heat exchanger, by means of an injection of an additional compressed gas in a position such that it induces in said group of channels a flow of gaseous fluid coming from the exchanger.
  • the additional gas injection control can be done manually intermittently, or according to a sequence determined for each group of channels of the exchanger under the control of an automatic control system.
  • the injection of the additional gas under pressure can be done in the axis or in the plane of symmetry of the channels, or even in an inclined manner depending on the applications.
  • the injection of the additional compressed gas is preferably carried out by means of nozzles placed in a position upstream of the mouth of each channel of the heat exchanger.
  • the invention also relates to an automatic device for periodically cleaning the surfaces of a heat exchanger for gaseous fluids which allows the implementation of the method of the invention.
  • the device of the invention comprises injection pipes for additional compressed gas opening upstream, in front of the openings of the channel groups and an injection control device suitable for successively and periodically controlling for each group of channels, an injection of additional compressed gas inducing in the group of channels a flow of gaseous fluid coming from the exchanger, thus causing the vibration of the elastic elements being in the group of channels.
  • the elastic elements are preferably fixed at their two ends in the vicinity of the two ends of the channels.
  • the elastic elements may only be fixed at their upper end, close to the opening, the lower end of the elastic elements then being free.
  • the injection pipes preferably have injection nozzles which direct the flow of additional compressed gas towards the upper opening of the channels. These nozzles can also serve as a fixing for the upper part of the elastic elements, either directly or by means of additional elements integral with the nozzles or fixed to the nozzles.
  • the elastic elements are arranged in the vertical channels of the heat exchanger in the immediate vicinity of their internal walls, without however coming into contact with said walls during normal operation of the exchanger, that is to say outside cleaning periods.
  • the elastic elements therefore act as turbulators disturbing the boundary layer in the vicinity of the internal walls of the channels, which makes it possible to circulate the gas flow at a low speed which is preferably between approximately 8 and 12 m / second, and more particularly between approximately 8 and 10 m / second.
  • the elastic elements consist of metal wires wound in a helix.
  • metal wires provided with a plurality of blades extending radially, advantageously aerodynamically profiled, so as to vibrate the whole of the elastic element by the action of the gas flow induced by the additional compressed gas from the injection lines.
  • the heat exchanger is of the cross-flow tubular type in which hot and dusty gases flow inside vertical tubes 1, preferably from top to bottom. low.
  • the cooling air flows transversely to the direction of the hot and dusty gases, outside of the tubes 1 and between them.
  • the invention could also be applied, without notable modifications, to an exchanger of the tube-shell type with flow parallel to the tubes of the cooling gases, or to another type, and in particular to a heat exchanger. with plates.
  • the tubes 1 are fixed to the upper 2a and lower 2b head plates by welding according to a conventional method in the construction of exchangers of this type.
  • the tubes 1 thus communicate with an upper plenum 3 which is used for the admission or extraction of hot and dusty gases through an intake or extraction orifice which is not shown in the figures, and with a lower plenum 4 comprising an extraction or admission orifice also not shown.
  • the lower plenum 4 preferably has, as illustrated in FIG. 1, the shape of a hopper making it possible to facilitate the recovery of the solid particles which will settle there during the cleaning operations.
  • the dimensioning of the gas passage sections is chosen so that a flow speed of between approximately 8 and 12 m / second, and preferably approximately 8 and 10 m / second, is obtained. It is indeed advisable not to adopt a too high flow speed, in order not to create exaggerated pressure drops. Furthermore, a flow rate that is too low would cause prohibitive bulk for the entire apparatus.
  • the choice of the diameter of the tubes is made so as to allow the passage of gases with the suitable flow speed which has just been mentioned, while allowing the insertion of the elastic cleaning elements.
  • the elastic elements are formed in the example illustrated in Figures 1 and 2 by a metal wire 5 wound in a helix and forming a spring.
  • the springs 5 are rigidly fixed at their upper 6 and lower 7 ends, which both protrude from the upper and lower ends of the tubes 1.
  • the lower ends 7 of the springs 5 are fixed to a grid 8 itself rigidly mounted by means not illustrated in the figures, in the lower plenum 4.
  • the grid 8 has a mesh identical to that of the axes of the tubes 1 of the exchanger. It will however be understood that a different attachment could perfectly well be envisaged.
  • the lower part 7 of the spring 5 is fixed by means of hooks 9 allowing easy disassembly.
  • hooks 9 allowing easy disassembly.
  • other means could be used, and in particular a bolting or pinning fastening, insofar as easy disassembly remains possible.
  • injection nozzles 10 for an additional compressed gas which can for example be compressed air or steam pressurized water.
  • the nozzles 10 have ends of small diameter which can be for example between 4 and 10 mm approximately, it being understood that the choice of the diameter of the injection nozzle depends on the diameter of the tubes 1 of the exchanger.
  • the nozzles 10 are centered on the axes of the tubes 1 and placed at a certain distance above the opening of the tubes 1. It would be possible, in a variant, for the axis of the nozzles 10 to have a certain inclination relative to the 'axis of the tubes 1, which would then direct the compressed additional gas jet towards the periphery of the elastic elements 5, causing a different excitation.
  • each injection pipe 12 equipped with its plurality of vertical tubes 11 and injection nozzles 10, allows the injection of gas into a row of tubes 1 ( Figure 2).
  • a control valve 14 which can be actuated manually or by means of a solenoid valve controlled by an automatic mechanism, allows the periodically controlled injection of the additional compressed gas contained in the reservoir 13, for this row of tubes 1.
  • FIG. 3 there is seen a first embodiment of such an attachment.
  • the injection tube 11 is provided with longitudinal fins 15 in which are made perforations 16 allowing the passage and the winding of the upper end of the spring 5.
  • FIG. 4 shows an alternative embodiment in which the spring 5 is terminated by a winding 17 of smaller diameter than the spring 5, the winding 17 being threaded on the end of the injection tube 11 and blocked by a clamping element 18. It will of course be noted that 'it would be perfectly possible to fix the upper ends of the springs 5 by other means, for example directly on the injection pipe 12, or else on a separate support rigidly mounted in the upper plenum 3.
  • the device of the invention operates in the following manner.
  • a gas is injected into a row of tubes 1 additional tablet at a pressure of the order of 2 to 6 bars via the nozzles 10.
  • This injection which is carried out for a relatively short duration, for example between 1 / 10th of a second and a few seconds, instantly induces a flow of fluid gas from the upper plenum 3 and the tubes 1 of the adjacent rows.
  • This induced gaseous fluid flow rate is of the order of four to six times the flow rate of the additional compressed gas injected through the nozzles 10.
  • the flow speed thus created inside the tubes 1 is therefore very high.
  • the amount of movement thus provided is communicated to the springs 5 and the resulting agitation is damped in the flow and along the walls of the tubes 1 by impact and scraping, which results in cleaning and maintenance of the state. internal surfaces of the tubes 1 of the heat exchanger.
  • FIG. 5 illustrates a variant of the device of the invention in which the upper end of each tube 1 of the exchanger is fitted with a mouth piece 19 partially penetrating inside the tube 1.
  • the piece of mouth 19 can be fixed to tube 1 by threading as illustrated in FIG. 5, or by any other means such as snap-fastening, welding, gluing, etc.
  • the mouthpiece 19 is profiled in the manner of a nozzle convergent, so as to induce a greater flow of gaseous fluid under the effect of the injection of the additional compressed gas by the nozzles 10 placed as before at a certain distance from the mouth of the tubes 1. It is thus possible to further reduce the flow rate of the additional compressed gas necessary for the periodic cleaning operation.
  • FIG. 6 schematically shows an elastic element of different structure which can be used in the context of the invention.
  • the blades 21 then cause the cleaning by impacts and scraping as previously.
  • the elastic element constituted by the spring 5 or by the cable 20 provided with the fins 21, or even by any other equivalent means be placed inside the tube 1 or of the vertical channel of the exchanger, so as to be in close proximity to its internal walls, without however coming into contact with said walls during normal operation of the heat exchanger outside of the cleaning periods.
  • the boundary layer is effectively disturbed by portions of the elastic element located in the vicinity of the internal walls of the tubes 1 and cleaning is better ensured during the injection of compressed gas.
  • the elastic elements have been rigidly fixed at their upper and lower ends. It will however be understood that it would be possible in a variant not to fix the lower ends of the elastic elements. These then remain free of any hindrance in the vicinity of their lower end 7 and can somehow float in the gas flow. The vibration characteristics caused by the injection of additional compressed gas and the induced gas flow are then different and can be adapted to certain particular problems of clogging.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
  • Cleaning In General (AREA)
  • Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
  • Cleaning By Liquid Or Steam (AREA)
  • Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
  • Gas Separation By Absorption (AREA)
EP86114805A 1985-10-25 1986-10-24 Procédé et dispositif automatique de nettoyage d'un échangeur de chaleur pour fluides gazeux Expired EP0219882B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT86114805T ATE39284T1 (de) 1985-10-25 1986-10-24 Verfahren und automatische vorrichtung zum reinigen eines waermetauschers fuer gasfoermige fluide.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8515923A FR2589229B1 (fr) 1985-10-25 1985-10-25 Procede et dispositif automatique de nettoyage d'un echangeur de chaleur pour fluides gazeux
FR8515923 1985-10-25

Publications (2)

Publication Number Publication Date
EP0219882A1 EP0219882A1 (fr) 1987-04-29
EP0219882B1 true EP0219882B1 (fr) 1988-12-14

Family

ID=9324227

Family Applications (1)

Application Number Title Priority Date Filing Date
EP86114805A Expired EP0219882B1 (fr) 1985-10-25 1986-10-24 Procédé et dispositif automatique de nettoyage d'un échangeur de chaleur pour fluides gazeux

Country Status (16)

Country Link
US (1) US4825940A (da)
EP (1) EP0219882B1 (da)
JP (1) JPS6325497A (da)
KR (1) KR870004285A (da)
AT (1) ATE39284T1 (da)
AU (1) AU590344B2 (da)
BE (1) BE903577A (da)
BR (1) BR8605213A (da)
CA (1) CA1272184A (da)
DE (1) DE3661444D1 (da)
DK (1) DK161857C (da)
ES (1) ES2004834B3 (da)
FR (1) FR2589229B1 (da)
GR (1) GR3000009T3 (da)
NO (1) NO167327C (da)
PT (1) PT83596B (da)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19740883C1 (de) * 1997-09-16 1999-02-25 Renzmann Und Gruenewald Gmbh Wärmeaustauscher

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0672754B2 (ja) * 1987-09-30 1994-09-14 株式会社ジャパンエナジー 熱交換器の伝熱管におけるスケール等の付着防止装置
FR2639425B1 (fr) * 1988-11-18 1991-06-07 Total France Procede et dispositif de nettoyage d'un tube dans lequel circule un fluide, et utilisation dans les tubes d'echangeurs de chaleur
CA2100734C (en) * 1993-07-16 1998-05-26 Normand Verret Heat exchanger for dusty environment
DE19544185C2 (de) * 1995-11-28 1998-08-13 Renzmann Und Gruenewald Gmbh Wärmetauscher
DE19721927C1 (de) * 1997-05-26 1999-02-25 Renzmann Und Gruenewald Gmbh Wärmetauscher
DE19723971C1 (de) * 1997-06-06 1999-02-25 Renzmann Und Gruenewald Gmbh Wärmetauscher
US5799622A (en) * 1997-06-30 1998-09-01 Decker Manufacturing Furnace heat exchanger tube cleaning system
FR2787564B1 (fr) * 1998-12-22 2001-03-02 Total Raffinage Distribution Perfectionnements apportes aux tubes d'echangeurs thermiques, en vue d'eviter le colmatage de leur entree par des materiaux en suspension
US7093649B2 (en) * 2004-02-10 2006-08-22 Peter Dawson Flat heat exchanger plate and bulk material heat exchanger using the same
FR2890162B1 (fr) * 2005-08-30 2007-11-30 Total France Sa Dispositif reducteur d'encrassement d'un echangeur thermique tubulaire.
TWI428168B (zh) * 2011-09-27 2014-03-01 Wang Yung Chuan Lee Anti - fouling device for membrane filter
AT517955B1 (de) * 2016-05-18 2017-06-15 Ökofen Forschungs- Und Entw M B H Heizeinrichtung
CN108716805A (zh) * 2018-07-02 2018-10-30 天津商业大学 自动除霜的绕片换热器
EP3786561B1 (en) 2019-09-02 2022-12-14 Orion Engineered Carbons IP GmbH & Co. KG Anti-fouling device for heat exchangers and its use

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US2795400A (en) * 1954-07-22 1957-06-11 Air Preheater Heat transfer elements for rotary regenerative heaters
FR1248787A (fr) * 1959-03-13 1960-12-23 Schmidt Sche Heissdampf Dispositif de nettoyage des tubes d'échangeurs de chaleur sur la face située du côté des gaz de fumée
US3364983A (en) * 1965-01-04 1968-01-23 Cabot Corp Heat exchange process and apparatus
BE666832A (da) * 1964-07-13
US3288204A (en) * 1964-12-11 1966-11-29 Air Preheater Suspended chain matrix
JPS523903A (en) * 1975-06-24 1977-01-12 Kikan Buhin Seizo Kk Smoke tube dust cleaner
DE2948201C2 (de) * 1979-11-30 1985-09-26 Degussa Ag, 6000 Frankfurt Vorrichtung und Verfahren zum periodischen Abreinigen von Wärmeaustauscherrohren von Feststoffablagerungen und Verwendung dieser Vorrichtung
SU996841A1 (ru) * 1981-03-04 1983-02-15 за витель В. М- Климов Устройство дл очистки трубок теплообменных аппаратов
US4583585A (en) * 1981-07-22 1986-04-22 Elf France System for cleaning tube-type exchangers automatically during operation
SU1143964A1 (ru) * 1983-07-27 1985-03-07 Литовский Научно-Исследовательский Институт Механизации И Электрификации Сельского Хозяйства Теплообменник

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENTS ABSTRACTS OF JAPAN, vol. 1, no. 51, 18 mai 1977, page 252 M 77; & JP-A-52 3903 (KIKAN BUHIN SEIZO K.K.) 01-12-1977 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19740883C1 (de) * 1997-09-16 1999-02-25 Renzmann Und Gruenewald Gmbh Wärmeaustauscher

Also Published As

Publication number Publication date
KR870004285A (ko) 1987-05-08
FR2589229A1 (fr) 1987-04-30
DK161857C (da) 1992-01-20
GR3000009T3 (en) 1989-09-29
ES2004834B3 (es) 1989-12-01
BE903577A (fr) 1986-05-05
DK511686A (da) 1987-04-26
DE3661444D1 (en) 1989-01-19
NO864267L (no) 1987-04-27
AU6437986A (en) 1987-04-30
AU590344B2 (en) 1989-11-02
DK511686D0 (da) 1986-10-24
CA1272184A (fr) 1990-07-31
NO167327B (no) 1991-07-15
FR2589229B1 (fr) 1988-01-08
EP0219882A1 (fr) 1987-04-29
NO167327C (no) 1991-10-23
DK161857B (da) 1991-08-19
JPS6325497A (ja) 1988-02-02
NO864267D0 (no) 1986-10-24
PT83596A (fr) 1986-11-01
US4825940A (en) 1989-05-02
PT83596B (pt) 1992-10-30
BR8605213A (pt) 1987-07-28
ATE39284T1 (de) 1988-12-15

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