EP0325758B1 - Dampfkondensator - Google Patents
Dampfkondensator Download PDFInfo
- Publication number
- EP0325758B1 EP0325758B1 EP88121053A EP88121053A EP0325758B1 EP 0325758 B1 EP0325758 B1 EP 0325758B1 EP 88121053 A EP88121053 A EP 88121053A EP 88121053 A EP88121053 A EP 88121053A EP 0325758 B1 EP0325758 B1 EP 0325758B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- steam
- nest
- cooler
- condenser
- bundle
- 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 - Lifetime
Links
- 239000007789 gas Substances 0.000 claims description 12
- 239000000498 cooling water Substances 0.000 claims description 11
- 239000000203 mixture Substances 0.000 claims description 9
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 9
- 230000004888 barrier function Effects 0.000 claims description 4
- 230000000149 penetrating effect Effects 0.000 claims description 3
- 239000011796 hollow space material Substances 0.000 claims 2
- 239000003990 capacitor Substances 0.000 description 9
- 230000008901 benefit Effects 0.000 description 5
- 238000009833 condensation Methods 0.000 description 4
- 230000005494 condensation Effects 0.000 description 4
- 230000035508 accumulation Effects 0.000 description 3
- 238000009825 accumulation Methods 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
- 239000001301 oxygen Substances 0.000 description 3
- 229910052760 oxygen Inorganic materials 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 238000011010 flushing procedure Methods 0.000 description 2
- 238000005192 partition Methods 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 230000001133 acceleration Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000007872 degassing Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000002631 hypothermal effect Effects 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000010327 methods by industry Methods 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000010926 purge Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000001172 regenerating effect Effects 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000004781 supercooling Methods 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28B—STEAM OR VAPOUR CONDENSERS
- F28B9/00—Auxiliary systems, arrangements, or devices
- F28B9/10—Auxiliary systems, arrangements, or devices for extracting, cooling, and removing non-condensable gases
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28B—STEAM OR VAPOUR CONDENSERS
- F28B1/00—Condensers in which the steam or vapour is separate from the cooling medium by walls, e.g. surface condenser
- F28B1/02—Condensers in which the steam or vapour is separate from the cooling medium by walls, e.g. surface condenser using water or other liquid as the cooling medium
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S165/00—Heat exchange
- Y10S165/184—Indirect-contact condenser
- Y10S165/205—Space for condensable vapor surrounds space for coolant
- Y10S165/207—Distinct outlets for separated condensate and gas
- Y10S165/211—Distinct outlets for separated condensate and gas including concave member adjacent to vapor outlet and partially covering a group of coolant tubes
Definitions
- the invention relates to a steam condenser in which the steam is deposited on tubes through which cooling water flows and which are combined in separate bundles spaced apart from one another, the tubes of a bundle arranged in rows enclosing a cavity in which a cooler for the non-condensable gases is arranged.
- Such a steam condenser is known from Swiss Patent No. 423 819.
- the condenser tubes are arranged in several, so-called sub-bundles in a condenser housing.
- the steam flows through an exhaust pipe into the condenser housing and is distributed in the room through flow channels. These narrow in the general direction of the flow in such a way that the flow velocity of the steam in these channels remains at least approximately constant.
- the free inflow of steam to the outside tubes of the partial bundles is ensured.
- the steam then flows through the bundles with a small resistance due to the low pipe depth.
- the partial bundles are arranged in the condenser next to each other in such a way that flow channels arise between them, which appear in the sectional view in the same order of magnitude as the sub-bundles themselves.
- the tubes in the successive rows form a self-contained wall, which is preferably of the same thickness throughout.
- This known condenser has the advantage that due to the loose arrangement of the sub-bundles, all peripheral tubes of a sub-bundle are well supplied with steam without noticeable loss.
- the requirement for at least approximately the same "wall thickness" of the tube-shaped sub-bundle around the cavity results in a relatively large overall height of the sub-bundle.
- This known solution is less suitable for steam condensers of small power plants up to 100 MW electrical, in chemistry or in process engineering, in which the amount of steam generated is lower.
- the surface capacitors in the last-mentioned systems are predominantly designed in a round shape.
- These concepts are usually carried out with one-sided steam flushing of the bundle through a V-cut arranged in the middle of the condenser.
- the rivers are arranged vertically from the center outwards with the air coolers on both sides of the jacket.
- the typical weak points of these concepts lie in the lack of condensation performance of the lower pipe sections as well as in consequent subcooling and high oxygen content in the condensate, as well as in poor partial load behavior.
- the invention is therefore based on the object of creating a capacitor of the type mentioned of any size and of a preferably simple external shape, which has the advantages of the partial bundle concepts mentioned above.
- this is achieved in that two sub-bundles are provided which are exposed to the steam over their entire periphery, the bundle shape being selected independently of the external shape of the condenser in such a way that between the bundles on the one hand and between each bundle and the condenser wall initially one convergent _ the steam accelerating _ flow channel is formed and then a _ diverting the steam deflecting _ part is formed, and that the cooler for the non-condensable gases within a bundle is in the plane in which outside the bundle the convergent steam channel in ignores the divergent part.
- the advantage of the invention can be seen in the fact that as a result of the deliberately implemented pressure reduction in the flow-through alleys at the level of the air cooler on both sides of the respective bundle, the steam-side pressure drop across the bundle is approximately constant, so that there is a homogeneous pressure gradient in the direction of the cooler . With this measure, good steam flushing through the bundle is achieved.
- the steam in the alleys is decelerated to zero with pressure recovery at the level of the condensate collector. This causes an increase in the saturation temperature of the steam and thus a regression of the condensate supercooling that has taken place and the oxygen concentration in the condensate.
- cooling water first acts on the lower tubes of each bundle, the cooler for the non-condensable gases preferably being arranged inside the lower tube bundle which is acted on first. This supports the regenerative properties of the bundle configuration.
- the tubes of the cooler in the cavity of the bundle are provided with a cover plate, which is also designed as a closed suction channel that communicates with the cooler zone via panels.
- the multifunctional cover plate protects the cooler pipes from the condensate running down.
- the heat exchanger shown is a round surface condenser as it is suitable for the so-called underfloor arrangement. As a rule, such capacitors have exchange areas between 500 and 2500 m2.
- the steam flows into the elongated condenser neck 1 via an evaporation nozzle (not shown) with which the condenser hangs on the turbine.
- the best possible homogeneous flow field is generated therein in order to carry out a clean steam purging of the bundles 2 arranged downstream over their entire length.
- Deflection blades 3 can be provided in the condenser neck 1 for the purpose of clean distribution of the steam.
- the condensation chamber inside the cylindrical condenser jacket contains two separate sub-bundles 2. This has the aim, among other things, that a partial shutdown on the cooling water side can also be carried out during system operation, for example for the purpose of an inspection of the disconnected bundle on the cooling water side.
- the independent application of cooling water is expressed by the fact that, according to FIG. 1, the water chambers are divided into two compartments by a vertical partition wall 10.
- the bundles consist of a number of tubes 5, which are fastened at their two ends in tube plates 6. Beyond the tube sheets, the water chambers 7 are arranged.
- there is a two-flow cooling water system selected which means that the inlet and outlet water chambers are on one side of the condenser and the reversal chambers on the other side.
- the lower bundle part is chosen to be the first flow, ie the cooling water is introduced there. Accordingly, in FIG. 1 the lower water chamber connections form the inlet pipes 8 and the upper water chamber connections the outlet pipes 9.
- Horizontal dividing walls 11 each divide the chambers into inlet or Outlet chambers.
- the condensate flowing off from the bundles 2 is collected in the condensate collecting vessel 12 and from there it reaches the water / steam circuit, not shown.
- a cavity 13 is formed in the interior of each bundle 2, in which the vapor enriched with non-condensable gases - hereinafter referred to as air - collects.
- An air cooler 14 is accommodated in this cavity 13. The steam / air mixture flows through this air cooler, with most of the steam condensing. The rest of the mixture is suctioned off at the cold end.
- the bundles are designed in such a way that all pipes in the periphery have a good flow of steam without noticeable pressure loss.
- the existing flow paths between the two bundles 2 on the one hand and between each bundle and their adjacent condenser wall are designed as follows:
- the predominant first part 15 of the flow path between the beginning and end of the bundle is designed to be convergent.
- the flowing steam experiences a spatial acceleration with a corresponding decrease in the static pressure. This is approximately homogeneous on both sides of the bundle.
- account must be taken of the fact that the steam mass flow becomes increasingly smaller as a result of the condensation.
- the steam according to the invention should now be decelerated to zero speed with a simultaneous pressure recovery. This is achieved in that the second part 16 of the steam lane is made divergent. It also applies here Note that the channel expansion does not have to be optically recognizable due to the increasing decrease in the mass flow. The decisive factor is that the residual steam flowing towards the condenser bottom creates a dynamic pressure there. This deflects the steam and also supplies the lower parts of the bundle. The increase in temperature caused by the dynamic pressure benefits the condensate flowing down from pipe to pipe by heating up again if it has cooled below the saturation temperature. This ensures two advantages: There are no thermodynamic losses due to condensate hypothermia and the oxygen content of the condensate is reduced to a minimum.
- the air cooler 14 is arranged in the interior of the bundle at the level at which the bundle of pressure runs through a relative minimum in the flow through the bundle on both sides.
- the air cooler according to FIG. 2 is thus in the middle of the bundle, specifically in the first flow directly below the parting plane of the two flows.
- the bundle is designed in such a way that the steam suction into the cavity 13 - taking into account the effective pressure at the pipe periphery and due to the different pipe row thickness - acts homogeneously in the radial direction over all pipes adjacent in the cavity 13. This results in a homogeneous pressure gradient and thus a clear flow direction of the steam and the non-condensable gases towards the air cooler.
- the air cooler 14 has the task of removing the non-condensable gases from the condenser. During this process, the steam losses are to be kept as low as possible. This is achieved in that the steam / air mixture is accelerated in the direction of the suction duct 17. The high speed results in good heat transfer, which leads to extensive condensation of the residual steam. In order to accelerate the mixture, the cross section in the direction of flow is increasingly smaller, as can be seen in FIG. 3. The air is sucked off through orifices 18 into the channel 17. These screens are distributed several times over the entire length of the condenser and ensure that the suction effect is homogeneous in all compartments of the condenser.
- a part of the wall of the suction channel 17 is also designed as a cover plate 19. This sheet is placed over the pipes of the cooler and protects them from the steam and condensate flow flowing downwards. This also specifies the direction of entry of the mixture to be cooled, namely from bottom to top towards the screens 18.
- vapor barriers 21 The free space created by the omission of the pipes is equipped by means of vapor barriers 21.
- the primary goal of these is to prevent steam bypass.
- These are longitudinal, baffle-like sheets that have through openings (not shown) for the suction lines 20. These baffles are designed so that they do not prevent vertical steam or condensate exchange. In the direction of the steam lane / cooler, they form a flow obstacle that should have the same pressure drop as the original pipe.
- an influence arrangement can also be implemented.
- the non-condensable gases are led out of the condenser in the longitudinal direction instead of across the bundle.
- the suction line penetrates one of the tube sheets and the corresponding water chamber.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CH23088 | 1988-01-22 | ||
CH230/88 | 1988-01-22 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0325758A1 EP0325758A1 (de) | 1989-08-02 |
EP0325758B1 true EP0325758B1 (de) | 1991-03-06 |
Family
ID=4182257
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP88121053A Expired - Lifetime EP0325758B1 (de) | 1988-01-22 | 1988-12-16 | Dampfkondensator |
Country Status (7)
Country | Link |
---|---|
US (1) | US4967833A (es) |
EP (1) | EP0325758B1 (es) |
AU (1) | AU607036B2 (es) |
CA (1) | CA1309908C (es) |
DE (1) | DE3861964D1 (es) |
ES (1) | ES2021132B3 (es) |
YU (1) | YU239088A (es) |
Families Citing this family (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE4141132C2 (de) * | 1991-12-13 | 1995-06-29 | Preussenelektra Ag | Dampfkondensator |
EP0561012B1 (de) * | 1992-03-16 | 1996-05-29 | Asea Brown Boveri Ag | Verfahren und Einrichtung zum Behandeln von Wasser in einem Oberflächenkondensator |
DE4311118A1 (de) * | 1993-04-05 | 1994-10-06 | Abb Management Ag | Dampfkondensator |
US6269867B1 (en) | 1994-12-02 | 2001-08-07 | Hitachi, Ltd | Condenser and power plant |
DE69530047T2 (de) * | 1994-12-02 | 2004-01-29 | Hitachi Ltd | Kondensator und Kraftwerk |
JP3735405B2 (ja) * | 1995-12-15 | 2006-01-18 | 株式会社東芝 | 復水器 |
DE19642100B4 (de) * | 1996-10-12 | 2011-09-29 | Alstom | Dampfkondensator |
EP0967451A1 (de) | 1998-06-24 | 1999-12-29 | Asea Brown Boveri AG | Dampfkondensator |
US9217566B2 (en) * | 2007-03-27 | 2015-12-22 | Boyle Energy Services & Technology, Inc. | Method and apparatus for commissioning power plants |
CN104093942B (zh) | 2012-02-10 | 2015-10-21 | 阿尔斯通技术有限公司 | 水/蒸汽循环和用于操作其的方法 |
DE102018118275A1 (de) * | 2018-07-27 | 2020-01-30 | Valeo Siemens Eautomotive Germany Gmbh | Rotoranordnung für eine elektrische Maschine, elektrische Maschine für ein Fahrzeug und Fahrzeug |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1764716A (en) * | 1926-02-11 | 1930-06-17 | Elliott Co | Condenser |
US1796708A (en) * | 1929-12-07 | 1931-03-17 | Worthington Pump & Mach Corp | Condenser |
US2663547A (en) * | 1949-05-25 | 1953-12-22 | Lummus Co | Condenser deaerator |
US2869833A (en) * | 1957-04-03 | 1959-01-20 | Worthington Corp | Modular heat exchanger |
CH423819A (de) * | 1965-01-15 | 1966-11-15 | Bbc Brown Boveri & Cie | Kondensationsanlage für Dampfturbinen-Abdampf |
CH462212A (de) * | 1967-09-08 | 1968-09-15 | Bbc Brown Boveri & Cie | Verfahren und Anlage zum Kondensieren von Dampf |
JPS5327705A (en) * | 1976-08-27 | 1978-03-15 | Hitachi Ltd | Multitube type heat exchanger |
JPS53147103A (en) * | 1977-05-27 | 1978-12-21 | Hitachi Ltd | Multitubular system heat exchager |
JPS5914682B2 (ja) * | 1980-09-29 | 1984-04-05 | 株式会社日立製作所 | 給水加熱器 |
-
1988
- 1988-12-16 ES ES88121053T patent/ES2021132B3/es not_active Expired - Lifetime
- 1988-12-16 DE DE8888121053T patent/DE3861964D1/de not_active Expired - Lifetime
- 1988-12-16 EP EP88121053A patent/EP0325758B1/de not_active Expired - Lifetime
- 1988-12-29 YU YU02390/88A patent/YU239088A/xx unknown
-
1989
- 1989-01-17 US US07/297,388 patent/US4967833A/en not_active Expired - Lifetime
- 1989-01-17 CA CA000588406A patent/CA1309908C/en not_active Expired - Lifetime
- 1989-01-19 AU AU28618/89A patent/AU607036B2/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
CA1309908C (en) | 1992-11-10 |
EP0325758A1 (de) | 1989-08-02 |
YU239088A (en) | 1991-08-31 |
US4967833A (en) | 1990-11-06 |
ES2021132B3 (es) | 1991-10-16 |
AU2861889A (en) | 1989-07-27 |
AU607036B2 (en) | 1991-02-21 |
DE3861964D1 (de) | 1991-04-11 |
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