WO2000006963A1 - Procede et appareil permettant d'empecher l'accumulation de boues - Google Patents

Procede et appareil permettant d'empecher l'accumulation de boues Download PDF

Info

Publication number
WO2000006963A1
WO2000006963A1 PCT/CZ1999/000024 CZ9900024W WO0006963A1 WO 2000006963 A1 WO2000006963 A1 WO 2000006963A1 CZ 9900024 W CZ9900024 W CZ 9900024W WO 0006963 A1 WO0006963 A1 WO 0006963A1
Authority
WO
WIPO (PCT)
Prior art keywords
tubes
medium
cleaning medium
channel
channel wall
Prior art date
Application number
PCT/CZ1999/000024
Other languages
English (en)
Inventor
Petr KRČMÁŘ
Original Assignee
Krcmar Petr
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=5464760&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=WO2000006963(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Krcmar Petr filed Critical Krcmar Petr
Priority to AU45995/99A priority Critical patent/AU4599599A/en
Publication of WO2000006963A1 publication Critical patent/WO2000006963A1/fr

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B37/00—Component parts or details of steam boilers
    • F22B37/02—Component parts or details of steam boilers applicable to more than one kind or type of steam boiler
    • F22B37/48—Devices for removing water, salt, or sludge from boilers; Arrangements of cleaning apparatus in boilers; Combinations thereof with boilers
    • F22B37/483—Devices for removing water, salt, or sludge from boilers; Arrangements of cleaning apparatus in boilers; Combinations thereof with boilers specially adapted for nuclear steam generators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B1/00—Methods of steam generation characterised by form of heating method
    • F22B1/02—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers
    • F22B1/023—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers with heating tubes, for nuclear reactors as far as they are not classified, according to a specified heating fluid, in another group
    • F22B1/025—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers with heating tubes, for nuclear reactors as far as they are not classified, according to a specified heating fluid, in another group with vertical U shaped tubes carried on a horizontal tube sheet
    • 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
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
    • F28F9/00—Casings; Header boxes; Auxiliary supports for elements; Auxiliary members within casings
    • F28F9/02—Header boxes; End plates
    • F28F9/0229—Double end plates; Single end plates with hollow spaces

Definitions

  • the inventions relates to a method for prevention of sludge piling in heat transfer devices more specifically such as steam generators and heal exchangers in which the heat transfer takes place between an internal medium flowing through a system of tubes attached to a tube sheet and an external medium flowing round the tubes within an outside lube space connecled to an inlet and outlet of the external medium and an apparatus for performing this method with heat transfer devices comprising a shell that defines a part of an outside tube space of a heat exchanger portion of the device connected to an inlet and outlet of an external medium and heat exchange tubes attached to a tube sheet separating the heat exchanger portion from a water box connected to an inlet and outlet of an internal medium
  • Another method consists in applying pressure pulse cleaning water to the area of the sludge sediments what of course requires putting the whole apparatus out of operation, nevertheless once firmly sticking sludge can be hardly removed in this way in full.
  • the primary object of the invention is to overcome the above difficulties arising out of the sludge formation in the area where the tubes are attached to the tube sheet by providing means which prevent the formation of sludge as of its beginning and avoid the necessity of its later removing. This brings about an increased life-time of the respective heat transfer device and preservation its substantial output characteristics.
  • Another object of the invention is to create an easy to manufacture and low cost of production apparatus for performing the new method.
  • the above object of the invention for prevention of sludge piling in heat transfer devices more specifically such as steam generators and heat exchangers in which the heat transfer takes place between an internal medium flowing through a complex of tubes attached to a tube sheet and an external medium flowing round the tubes within an outside tube space connected to an inlet and outlet of the external medium is achieved by the method according to the invention as defined in the characteristic part of claim 1 and according to which a controlled stream of a cleaning medium is introduced into the portion of the outside tube space adjacent to the tube sheet.
  • Said cleaning medium may consists essentially of the external medium or condensate obtained from the regenerated external medium.
  • the flow direction of the cleaning medium may be changed or reversed.
  • An apparatus for performing the method according to the invention with heat transfer devices comprises a shell that defines a part of an outside tube space of a heat exchanger portion of the device said space being connected to an inlet and outlet of an external medium and heat exchange tubes attached to a tube sheet separating the heat exchanger portion from a water box connected to an inlet and outlet of an internal medium and is provided by a channel installed in the region adjacent to the area where the tubes are attached to the tube sheet which channel comprises an upper channel wall and a peripheral channel wall and is provided by at least one opening for entry of a cleaning medium and at least one opening for the exit of the cleaning medium.
  • the peripheral channel wall is provided by two opposite situated systems of apertures the first system being connected to a chamber for entry and/or exit of the cleaning medium and the second system to the outside tube space, off the channel.
  • Each system of apertures in the peripheral channel wall is opened to a chamber for entry/ exit of the cleaning medium.
  • the upper channel wall is oblique in the flow direction of the cleaning medium.
  • a part of the channel is designed as a secondary cooler.
  • a conduit for outgoing cleaning medium connected to the exit chamber 15.6 I comprises an equipment for monitoring of the summary volume activity ⁇ .
  • the introduction of a stream of a cleaning medium into the lower part of the tubes situated in the area above the tube sheet has a favorable effect resulting in continuous splashing of sludge sediments that would otherwise create sludge piles on the outside surface of heat exchange tubes in this area and thus in avoiding the main reason for the increased tube corrosion in this critical area.
  • the foregoing alternative of the method and embodiments of the apparatus for performing thereof enable to improve the cleaning effect with a steam generator by using as a cleaning medium a condensate from the feed water regeneration which is approximately 100 times purer than the feed water as such and thus to avoid the tube corrosion caused by impurities contained otherwise in the feed water.
  • the cleaning effect may be enhanced by the reverse flow or changing the flow of the cleaning medium during the operation.
  • the described various alternative channel arrangements according to the invention contribute to create an optimal or more uniform cleaning medium flow rate profile across the whole channel what is very important with respect to the considerable number of tubes and restricted free space for passage of the cleaning medium between them. Further, the apparatus my be successfully used for continuous monitoring of the summary volume activity ⁇ and the results of such monitoring may be confirmed by measurement of the summary activity ⁇ on an evaporated sample.
  • Such detection process is substantial lower expensive than the existing conventional continuous monitoring of nitrogen 1 isotope.
  • the apparatus is easy to manufacture its design is universal and requires only minor interventions into the conventional steam generator or a heat exchanger structure and may be used practically unchanged without both described types heat exchange devices.
  • Fig. 1 is a sectional view of a conventional steam generator without the apparatus according to the invention
  • Fig. 2 is a detailed sectional view of the steam generator taking along its axis with the apparatus according to the invention - a channel
  • Fig. 3 is a cross sectional view taking along the line XI- XI of the steam generator in
  • Fig. 7 is a sectional view taking along the axis of a conventional heat exchanger without the apparatus according to the invention
  • Fig. 8 is a detailed sectional view of an heat exchanger with the apparatus according to the invention taken along its axis
  • Fig. 9 is a sectional view of the heat exchanger in Fig. 8 taking along the line X4 - X4
  • Fig. 10 is detailed sectional view of a heat exchanger with a secondary cooler
  • Fig. 1 1 is a sectional view of the heat exchanger in Fig. 10 taken along the line X7 - X7.
  • the known state of the art my be demonstrated on an conventional steam generator shown schematically in Fig. 1 without the apparatus according to the invention.
  • the steam generator is defined by a shell 1.0 consisting of a heat exchanger portion 3.0, in which the heat of the primary heat carrying medium, such as nuclear reactor cooling water flowing through tubes 2.4, is transferred to a heated medium - for example feed water flowing round the tubes within the outside tube space.
  • the primary heat carrying medium such as nuclear reactor cooling water flowing through tubes 2.4
  • the medium flowing inside the tubes will be designated as an internal medium and the medium flowing through the outside tube space will be designated as a external medium.
  • the steam generator includes such parts as a water box 2.0 provided by a partition wall 2.3 separating an inlet 2.1 and an outlet 2.2 of the internal medium and a steam portion 4.0 in which the generated steam is further treated.
  • a heat exchanger portion 3.0 and the water box 2.0 are separated by a tube sheet 1.1.
  • the plurality of tubes 2.4 arranged in juxtaposition and forming an U-tube bundle with an upward and downward section extend through a tube sheet 1.1 in which they are fixed and sealed. The position of the tubes 2.4 in the steam generator and the bundle is maintained by spacer plates 3.5. For the sake of clarity, only minor part of tubes is illustrated in Fig. 1.
  • the internal medium flows through the heat exchanger portion 3.0 so that it enters the water box 2.0 by the inlet 2.1 and passes through tubes 2.4 where its heat energy is conveyed to the external medium and than flows back to the water box 2.0 and leaves the steam generator through the outlet 2.2.
  • the flow direction of the internal medium through the steam generator is designated by arrows A.
  • the external medium such as feed water enters the steam generator by a water inlet 3.1 from the outside steam generator circuit which is not shown in the Fig. 1.
  • the feed water passes through a circular distributor 3.2 and an annual space 3.4 between the shell 1.0 and a bundle casing 3.3 into the lower part of the heat exchange portion 3.0 of the steam generator.
  • the flow direction of the external medium - feed water - in the heat exchanger is indicated by arrows B.
  • the feed water flows upwardly round each of tube 2.4 and re-emerges as steam that rises to the steam portion 4.0.
  • the steam After passing a moisture separator 4.3 the steam is dried in a dryer 4.2 and exits the steam generator through a steam outlet 4.1.
  • the media velocity in the outside tube space adjacent to the tube sheet 1.1 cannot be practically measured during the operation of the steam generator.
  • the fact that the sludge piles are formed on the outer tube surface is however clear evidence that the flow speed across this area is very low or approaches a zero value.
  • Fig. 2. and 3 illustrate the lower part of the steam generator in which the apparatus according to the invention is installed.
  • a channel 5.0 of substantially circular plan cross section which consists of an upper channel wall 5.8 and a side peripheral channel wall 5.9.
  • the channel 5.0 thus surrounds all heat exchange tubes 2.4 while the bottom of the channel 5.0 is constituted by the upper surface of the tube sheet 1.1.
  • the channel 5.0 is connected via an inlet distribution chamber 5.2 to an intake sleeve 5.1 which engages at its other end an outside external medium circuit that does not form a part of the invention and is not shown in the drawings.
  • the heat exchange tubes 2.4 extend through the channel 5.0 . by their both U-bundle branches. At the place where the tubes 2.4 pass through the upper channel wall 5.8 the upper channel wall openings are provided the diameter of which is greater than the diameter of the respective tubes 2.4.
  • the cleaning medium is withdrawn out of the outside external medium circuit and is forced by means of a non-illustrated pump to flow through the inlet sleeve 5.1 via the distribution chamber 5.2 into the channel 5.0 where it passes the entry apertures 5.3 in the peripheral channel wall 5.9.
  • the cleaning medium flows across the channel 5.0 round the individual tubes 2.4 and leaves the channel 5.0 through the holes 5.4 of the upper channel wall 5.8 and simultaneously through the exit apertures 5.5 in the opposite part of the peripheral channel wall 5.9.
  • the internal medium is mixed with the external medium - feed water.
  • the cross section of the enter chamber 5.2 is increasing in the flow direction of the cleaning medium in order to achieve desired and more equal flow distribution and pressure losses in the area of the entry chamber 5.2 .
  • the disposition of the enter apertures 5.3 and the exit apertures 5.5 in the respective diametrically opposed areas of the peripheral channel wall 5.9 is shown in Fig 4 and 5 as a view of a developed surface of the respective part of the peripheral channel wall taken along the line X2-X2 and X3-X3 respectively.
  • the channel 5.0 is connected to the collection exit chamber 5.6 and the outtake sleeve 5.7.
  • the cleaning medium flows via the collection exit chamber 5.6 through the outtake sleeve 5.7 out of the steam generator shell.
  • This arrangement enables a promptly detection of any escape of the internal, for example radioactive medium, into the external medium if the tightness of some of the tubes 2.4 is affected in the area adjacent the tube sheet 1.1.
  • This detection may be effected by continuous monitoring of the summary volume activity ⁇ and the results of such monitoring may be confirmed by measurement of the summary activity ⁇ on an evaporated sample.
  • the continuous monitoring of the summary volume activity ⁇ is effected as promptly as a continuous monitoring of nitrogen isotope in steam.
  • the place of failure is easy to identify and the method is substantially less expensive than a continuous monitoring of the nitrogen isotope.
  • the flow direction may be reversed by means of appropriate piping and valves included in the outside cleaning media circuit that is not shown in the respective drawings.
  • the effect of the cleaning media flow in the described critical sludge forming area of the tubes 2.4 above the tube sheet 1.1 is thus increased specifically on the back side of the tubes 2.4 in the flow direction.
  • the function of chambers 5.2 and 5.6 and sleeves 5.1 and 5.7 is changed from entry one to exit one and on the contrary.
  • FIG. 7 A conventional heat exchanger not provided by an apparatus according to the invention is shown in Fig. 7. It is expressly noted than the elements and parts of the heat exchanger which are analogous or equivalent to those of the steam generator as described in Example 1 are provided with the same reference numbers.
  • the heat exchanger defined by a shell 1.0 consists of two basic portions: a heat exchanger portion 3.0 and a water box 2.0 which are mutually separated by a tube sheet 1.1.
  • the plurality of tubes 2.4 arranged in juxtaposition and forming an U-tube bundle with an upward and downward sector extend through a tube sheet in which they are fixed and sealed. For the sake of clarity, only minor part of tubes is illustrated in Fig. 7.
  • the heat transfer takes place in the opposite sense in comparison with the steam generator i.e. from the external medium flowing through the outside tube space into the internal medium occupying the tubes 2.4.
  • the position of the tubes 2.4 in the bundle and shell is fixed by spacer plates 3.5.
  • the water box 2.0 is divided by a partition wall 2.3 separating an inlet 2.1 and an outlet 2.2 of the internal medium.
  • the internal medium enters through the inlet 2.1 of the water box 2.0, passes through the heat exchange tubes 2.4 receives the heat energy from the external heat carrying medium flowing through the outside tube space and leaves the heat exchanger via the water box 2.0 and outlet 2.2.
  • the external heat carrying medium enters the heat exchanger by an inlet 3.1 to continue into the outside tube space occupied by the bundle of the heat transfer tubes 2.4 where the heat transfer takes place and exits the heat exchanger via the outlet 3.2.
  • a channel 5.0 is formed having an upper wall 5.8 and an peripheral wall 5.9 surrounding all heat exchange tubes 2.4.
  • the channel 5.0 is connected via a collecting chamber 5.6 to an outtake sleeve 5.7.
  • the tubes 2.4 extend through the channel into the tube sheet 1.1.
  • holes 5.4 are provided with a diameter which is greater than the outer diameter of the respective tubes 2.4.
  • the external medium As a cleaning medium the external medium is used. A portion of the total volume of the external heat carrying medium is introduced into the channel 5.0 through exit apertures 5.3 arranged in like way as in the steam generator according to Fig. 4 in the peripheral channel wall 5.9. The rest of the cleaning medium enters the channel through holes 5.4 provided around the tubes 2.4 in the upper channel wall 5.8 . The external medium as the cleaning medium flows through the channel 5.0 round the individual tubes 2.4 and leaves the channel 5.0 via the exit apertures 5.5 arranged like in the steam generator in the peripheral channel wall 5.9. Further, the cleaning medium passes via the collection exit chamber 5.6 and the outtake sleeve 5.7 out of the heat exchanger shell.
  • the channel 5.0 may be formed so that the upper channel wall 5.8 is oblique in the flow direction of the cleaning medium in order to achieve desired and more equal flow distribution and pressure losses throughout the channel 5.0.
  • the collecting exit chamber 5.6 has a decreasing cross section in the flow direction, of the cleaning medium.
  • FIG. 10 and Fig. 1 An alternative design of the channel 5.0 is shown in Fig. 10 and Fig. 1 1.
  • a condensate secondary cooler 6.0 Above the tube sheet 1.1 in the upward cool sector of the tube bundle a condensate secondary cooler 6.0 is installed to form a first half of the channel 5.0.
  • the secondary cooler is connected through a transit conduit 6.1 and holes 5.4 to the outside tube space.
  • the second half of the secondary cooler 6.0 is connected via the collecting exit chamber 5.6 to the external medium outtake sleeve 5.7.
  • the external medium enters the channel 5.0 through a transit conduit 6.1 and holes 5.4, flows through several passes of the secondary cooler and enters the second half of the channel 5.0 engaging the downward hot sector of the bundle to leaf the heat exchanger via the collecting exit chamber 5.6 and the outtake sleeve 5.7.
  • This embodiment of the invention makes possible not only the secondary cooling of the condensate but also continuous splashing of the tubes 2.4 in the area above the tube sheet 1.1 by the cooled external medium used as the cleaning medium and prevention of undesired formation of sludge piles on the outer surface of the tubes 2.4.
  • the flow rate distribution as well as the pressure and form of the cleaning media stream inside the channel and close above the channel 5.0 may be determined by calculation with respect to both devices i.e. a steam generator and a heat exchanger.
  • two flow velocity limits in the channel 5.0 may be determined.
  • the lower limit is characterized by a flow velocity Rl at which the sludge ceases to make sediments and to create piles.
  • the upper limit is determined by a flow velocity R2 at which at certain critical sites of the channel the cleaning medium pressure falls under the saturated steam pressure and a cavitation phenomena occurs.
  • Such flow rates are to be determined individually with respect to each specific device.
  • the feed water may be utilized as the cleaning medium.
  • the condensate from the feed water regeneration may be used what implies an advantage that the content of impurities in the condensate are approximately 1000 times lesser that that in the feed water. The corrosion process caused by impurities contained in the cleaning medium may be thus avoided.
  • the outgoing external medium is used as the cleaning medium.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)

Abstract

L'invention se rapporte à un procédé permettant d'empêcher l'accumulation de boues dans des dispositifs de transfert de chaleur, notamment dans des générateurs de vapeur et des échangeurs thermiques dans lesquels le transfert de chaleur se produit entre un milieu interne qui s'écoule dans un ensemble de tubes (2.4) fixé à une plaque tubulaire (1.1) et un milieu externe qui s'écoule autour des tubes (2.4) à l'intérieur d'un espace tubulaire externe relié à une entrée (3.1) et une sortie (3.2) du milieu externe, un flux régulé d'un milieu de nettoyage étant introduit dans l'espace tubulaire externe adjacent à la plaque tubulaire (1.1). L'invention se rapporte à un appareil permettant la mise en oeuvre dudit procédé et comportant un canal (5.0) installé dans la région adjacente à la zone où les tubes (2.4) sont fixés à la plaque tubulaire (1.1), ledit canal (5.0) comportant une paroi supérieure (5.8) et une paroi périphérique (5.9) ainsi qu'au moins une ouverture (5.3) permettant l'entrée d'un milieu de nettoyage et au moins une ouverture (5.5) permettant l'évacuation dudit milieu de nettoyage.
PCT/CZ1999/000024 1998-07-24 1999-07-15 Procede et appareil permettant d'empecher l'accumulation de boues WO2000006963A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU45995/99A AU4599599A (en) 1998-07-24 1999-07-15 Method and apparatus for prevention of sludge piling

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CZPV2334-98 1998-07-24
CZ19982334A CZ286748B6 (cs) 1998-07-24 1998-07-24 Způsob odstraňování kalů a zařízení k jeho provádění

Publications (1)

Publication Number Publication Date
WO2000006963A1 true WO2000006963A1 (fr) 2000-02-10

Family

ID=5464760

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CZ1999/000024 WO2000006963A1 (fr) 1998-07-24 1999-07-15 Procede et appareil permettant d'empecher l'accumulation de boues

Country Status (3)

Country Link
AU (1) AU4599599A (fr)
CZ (1) CZ286748B6 (fr)
WO (1) WO2000006963A1 (fr)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE465512A (fr) *
US3833058A (en) * 1973-01-09 1974-09-03 Sulzer Ag Evaporator
US4261300A (en) * 1978-12-26 1981-04-14 Combustion Engineering, Inc. Nuclear steam generator
US4700773A (en) * 1985-09-18 1987-10-20 Borsig Gmbh Nested-tube heat exchanger
US5035283A (en) * 1989-09-09 1991-07-30 Borsig Gmbh Nested-tube heat exchanger
FR2689298A1 (fr) * 1992-03-24 1993-10-01 Framatome Sa Procédé d'élimination de dépôts de corrosion dans la partie secondaire d'un générateur de vapeur d'un réacteur nucléaire refroidi par de l'eau sous pression.

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE465512A (fr) *
US3833058A (en) * 1973-01-09 1974-09-03 Sulzer Ag Evaporator
US4261300A (en) * 1978-12-26 1981-04-14 Combustion Engineering, Inc. Nuclear steam generator
US4700773A (en) * 1985-09-18 1987-10-20 Borsig Gmbh Nested-tube heat exchanger
US5035283A (en) * 1989-09-09 1991-07-30 Borsig Gmbh Nested-tube heat exchanger
FR2689298A1 (fr) * 1992-03-24 1993-10-01 Framatome Sa Procédé d'élimination de dépôts de corrosion dans la partie secondaire d'un générateur de vapeur d'un réacteur nucléaire refroidi par de l'eau sous pression.

Also Published As

Publication number Publication date
CZ286748B6 (cs) 2000-06-14
CZ233498A3 (cs) 2000-03-15
AU4599599A (en) 2000-02-21

Similar Documents

Publication Publication Date Title
CA1080691A (fr) Generateur de vapeur a serpentin
JPH0250398B2 (fr)
GB1320788A (en) Tube bank heat exchanger and unit of such heat exchangers
US4308914A (en) Double plate flow distributor
US3425907A (en) Nuclear energy reactor plant having one or more heat exchangers
US4219077A (en) Multitubular heat exchanger used in a power plant
KR820001265B1 (ko) 관류 증기발생기의 블로우다운 장치
US3734176A (en) Heat exchanger assembly having a common fluid box
US3363678A (en) Multi-pressure surface condenser
WO2000006963A1 (fr) Procede et appareil permettant d'empecher l'accumulation de boues
US2452391A (en) Heat exchanger
US3130780A (en) Live steam reheater
US3880226A (en) Water quality analysis system with multicircuit single shell heat exchanger
JPS63151613A (ja) アンモニア合成から生じたガスを冷却する装置
US3348610A (en) Heat exchangers for cooling fresh cracked gases or the like
FR2106620B1 (fr)
US4528946A (en) Intermediate superheater
US3504737A (en) Heat exchangers
JPH076754B2 (ja) 熱交換器
CN217504441U (zh) 一种蒸汽加热装置
GB1572315A (en) Annular heat exchanger
US2056492A (en) Heat exchanger
AU655537B2 (en) Method and device for treating water in a surface condenser
RU2341750C1 (ru) Теплообменник
US3155158A (en) Header type tubular heat exchanger

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AU BG BR CA CN CU HR HU IL IN JP KP KR KZ MX NO PL RO RU SI SK TJ TM TR UA US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE

121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: CA

122 Ep: pct application non-entry in european phase