EP0308728B1 - Méthode d'exploitation d'un générateur de vapeur à passage unique - Google Patents

Méthode d'exploitation d'un générateur de vapeur à passage unique Download PDF

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Publication number
EP0308728B1
EP0308728B1 EP88114622A EP88114622A EP0308728B1 EP 0308728 B1 EP0308728 B1 EP 0308728B1 EP 88114622 A EP88114622 A EP 88114622A EP 88114622 A EP88114622 A EP 88114622A EP 0308728 B1 EP0308728 B1 EP 0308728B1
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EP
European Patent Office
Prior art keywords
heating surface
evaporator heating
steam generator
feed water
mass flow
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
Application number
EP88114622A
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German (de)
English (en)
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EP0308728A1 (fr
Inventor
Eberhard Dipl.-Ing. Wittchow
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.)
Siemens AG
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Siemens AG
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Filing date
Publication date
Application filed by Siemens AG filed Critical Siemens AG
Publication of EP0308728A1 publication Critical patent/EP0308728A1/fr
Application granted granted Critical
Publication of EP0308728B1 publication Critical patent/EP0308728B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B35/00—Control systems for steam boilers
    • F22B35/06—Control systems for steam boilers for steam boilers of forced-flow type
    • F22B35/10—Control systems for steam boilers for steam boilers of forced-flow type of once-through type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B29/00—Steam boilers of forced-flow type
    • F22B29/06—Steam boilers of forced-flow type of once-through type, i.e. built-up from tubes receiving water at one end and delivering superheated steam at the other end of the tubes
    • F22B29/12—Steam boilers of forced-flow type of once-through type, i.e. built-up from tubes receiving water at one end and delivering superheated steam at the other end of the tubes operating with superimposed recirculation during starting and low-load periods, e.g. composite boilers

Definitions

  • the invention relates to a method for operating a once-through steam generator in accordance with the preamble of patent claim 1.
  • Such a method is known from pages 751 to 753 from "VGB-Kraftwerkstechnik 56", number 12, Dec. 1976 and relates to the continuous steam generator with full load circulation of a combined gas / steam turbine system.
  • a constant amount of exhaust gas flows to the continuous steam generator regardless of its load from a gas turbine.
  • the excess air in the combustion chamber is always kept approximately the same size despite the different load of the continuous steam generator in that a partial flow of this exhaust gas from the gas turbine bypassing the combustion chamber and thus the first evaporator heating surface formed by the wall of this combustion chamber of the continuous steam generator on the flue gas side in front of the second evaporator heating surface in the convection space is introduced.
  • the feed water is constantly fed into both evaporator heating surfaces which are connected in parallel to each other, in proportions that always occur automatically.
  • the first evaporator heating surface formed by the wall of the combustion chamber absorbs less and less heat until this first evaporator heating surface only acts as feed water preheater at low load and most of the heat transfer to the second evaporator heating surface takes place in the convection room.
  • the invention is based on the task, in particular the drive power of the feed water pump for the once-through steam generator to reduce at full load of the continuous steam generator and thereby reduce the investment costs for a feed water pump, a feed water preheater and a feed water pipeline, but also to make the operation of the continuous steam generator more economical.
  • the method of the type mentioned in the introduction has the method steps according to the characterizing part of patent claim 1.
  • the feed water mass flow in the first evaporator heating surface forming the wall of the combustion chamber does not continue to rise above a certain load of the continuous steam generator, but that the increase in feed water mass flow required as the load increases further flows into the second evaporator heating surface located in the convection space.
  • the flow velocity and thus the friction pressure loss in the first evaporator heating surface do not increase further, and the feed water pump only has to overcome this friction pressure loss even at full load because of the second evaporator heating surface connected in parallel on the water side.
  • the second evaporator heating surface located in the convection space and switched off is not flowed through and is therefore not cooled, so that it in turn cannot cool the flue gas in the convection space.
  • the flue gas is therefore at a sufficiently high temperature so that a system connected downstream of the convection room and equipped with catalysts can work properly to remove nitrogen oxide from the flue gas.
  • Claims 2 and 3 are directed to advantageous developments of the method according to the invention.
  • the friction pressure loss to be overcome by the feed water pump insofar as it arises in the first evaporator heating surface, and thus also the output of the feed water pump can be set to the lowest possible value.
  • the continuous steam generator according to FIG 1 has a combustion chamber 2 with not shown, e.g. Coal dust burners that open into this combustion chamber 2.
  • the combustion chamber 2 is formed by a tube wall 3, which is a first evaporator heating surface.
  • the combustion chamber 2 is followed by a blasting chamber 4 with a horizontal train 5 on the flue gas side, which merges into a convection chamber 6 with a flue gas outlet channel 7.
  • the blasting chamber 4, the horizontal train 5 and the convection chamber 6 have steam-cooled, gas-tight tube walls.
  • High-pressure superheater and reheater heating surfaces 27 are arranged within the upper part of the blasting chamber 4, within the horizontal train 5 and within the upper part of the convection chamber 6.
  • a second evaporator heating surface 8 and an economizer heating surface 9 are also arranged within the convection space 6.
  • the flue gas outlet channel 7 leads to a system 10 containing catalysts for removing nitrogen oxide from the flue gas.
  • a feed water pipeline 11 with a feed water pump 12 and a feed water preheater 13 leads to the economiser heating surface 9.
  • the economizer heating surface 9 are connected on the water side via a pipe 14, which contains a flow meter 15, the pipe wall 3 forming the first evaporator heating surface and, via a further pipe 16, which contains a water control valve 17, the second evaporator heating surface 8 located in the convection chamber 6.
  • the second evaporator heating surface 8 with an upstream water control valve 17 and the tube wall 3 forming the first evaporator heating surface are connected in parallel on the water side and connected on the outlet side to a passage collector 18 which, as shown in FIG. 2, is in principle a tube into which the outlet 3a of the first evaporator heating surface and Outlet 8a of the second evaporator heating surface is located in a straight line of diameter of the tube opposite.
  • the tube wall of the blasting chamber 4 is followed by a water-steam separation container 19, the steam-side outlet 20 to a high-pressure superheater heating surface 27 and the water-side outlet 21, into which a pump 22 is connected, for lead the water-side entrance of the economiser heating surface 9.
  • This water-steam separation container 19 can also be connected behind the outputs of the tube wall 3 forming the first evaporator heating surface and the second evaporator heating surface 8.
  • the load of the continuous steam generator in percent of the full load is plotted on the abscissa and the feed water mass flow in the continuous steam generator in percent of the feed water mass flow at full load is plotted on the ordinate.
  • the solid line I represents the feed water mass flow through the pipeline 14 into the tube wall 3 forming the first evaporator heating surface and the dash-dotted line II represents the feed water mass flow through the pipeline 16 into the second evaporator heating surface 8, which is arranged in the convection space 6.
  • the water entering the two evaporator heating surfaces is also referred to as feed water.
  • the water control valve 17 is closed, and the feed water mass flow conveyed by the feed pump 12 through the pipe wall 3 forming the first evaporator heating surface is overlaid by a circulation water mass flow promoted by the pump 22, so that the total water mass flow through the pipe wall 3 is up to 40 at each partial load % of full load has the same value.
  • the water control valve 17 initially remains closed, the circulating water mass flow conveyed by the pump 22 is zero and the feed water mass flow through the tube wall 3 forming the first evaporator heating surface increases linearly with the load of the continuous steam generator.
  • the water control valve 17 Only when the flow meter 15 in the pipeline 14 a mass flow of feed water into the pipe wall 3, e.g. of 80% of the feed water mass flow in the continuous steam generator at full load indicates, the water control valve 17 is opened. When the load of the once-through steam generator is increased further, the water control valve 17 is always only opened so far that the feed water mass flow through the pipeline 14 into the pipe wall 3 always maintains the value 80% of the feed water mass flow in the flow steam generator at full load, while the part going beyond 80% this feed water mass flow is supplied to the second evaporator heating surface 8.
  • the friction pressure loss in the first evaporator heating surface consisting of the tube wall 3 is always greater than the friction pressure loss in the second evaporator heating surface 8 due to the strong heating in the combustion chamber 2 and the high flow rate required in the tubes of this tube wall 3, the friction pressure loss of the two increases on the water side evaporator heating surfaces connected in parallel at a load greater than 80% of the full load and even at full load of the once-through steam generator do not significantly depend on the friction pressure loss at 80% of the full load. As a result, the feed water pump output can be saved if the load of the once-through steam generator exceeds 80% of the full load.
  • the continuous steam generator according to FIG. 4 differs from that according to FIG. 1 in that the feed water mass flow for the second evaporator heating surface 8 is branched off in front of the economizer heating surface 9. Otherwise, the continuous steam generator according to FIG. 4 corresponds to that according to FIG. 1.
  • the economiser heating surface 9 can be made geometrically smaller than the continuous steam generator according to FIG. 1, so that the temperature of the flue gas that arrives at the system 10 is higher in the part-load range when the second evaporator heating surface 8 is switched off than in the continuous steam generator according to FIG. 1.
  • the water control valve 17 can still flow a small feed water mass flow into the second evaporator heating surface 8 in its closed position, so that this evaporator heating surface 8 is not heated to an unacceptably high degree in the flue gas at partial load.
  • the water control valve 17 is open above a certain partial load of the once-through steam generator, for example above 80% of the full load of the once-through steam generator, it can also be used as an injection valve for other heating surfaces which are connected downstream of the two evaporator heating surfaces on the water side.
  • the feed water mass flow into the once-through steam generator can therefore be briefly increased or reduced.
  • the water control valve 17 is opened or closed in the same cycle, so that the feed water mass flow into the first evaporator heating surface formed by the tube wall 3 is kept at the predetermined value.
  • the change in the feed water mass flow in the once-through steam generator has a very rapid effect on the temperature of the heating surfaces which are switched on the water side of the two evaporator heating surfaces, since the length of the tubes of the second evaporator heating surface 8 is considerably less than that of the tubes of the tube wall 3, which are the first Evaporator heating surface forms.

Claims (3)

1. Procédé pour faire fonctionner un générateur de vapeur à passage unique, comprenant une première surface de chauffage formant évaporateur, qui est formée par la paroi tubulaire d'une chambre de combustion, ainsi qu'une seconde surface de chauffage formant évaporateur, qui est montée en parallèle, du côté de l'eau, avec la première surface de chauffage formant évaporateur et qui se trouve dans une chambre de convection montée en aval, du côté du gaz de fumée, de la chambre de combustion et derrière, considéré dans le sens d'écoulement du gaz de fumée, une surface de chauffage formant surchauffeur, caractérisé en ce qu'il consiste à brancher, lorsqu'une valeur déterminée d'un courant massique d'eau d'alimentation dans le générateur de vapeur à passage unique est dépassée, le flux d'un courant partiel massique d'eau d'alimentation dans la seconde surface de chauffage formant évaporateur (8), en ouvrant une vanne de régulation d'eau (17) montée en amont dans le sens du débit de cette seconde surface de chauffage formant évaporateur (8) et, lorsque le courant massique d'eau d'alimentation devient inférieur à cette valeur déterminée, à le débrancher à nouveau en fermant la vanne de régulation d'eau (17).
2. Procédé suivant la revendication 1, caractérisé en ce qu'il consiste à régler le courant partiel massique d'eau d'alimentation dans la seconde surface de chauffage formant évaporateur (8) par la vanne de régulation d'eau (17) de manière que le courant partiel massique d'eau d'alimentation dans la première surface de chauffage formant évaporateur ne dépasse pas une valeur prescrite.
3. Procédé suivant la revendication 2, caractérisé en ce qu'il consiste à augmenter ou à réduire brièvement le courant massique d'eau d'alimentation dans le générateur de vapeur à passage unique.
EP88114622A 1987-09-21 1988-09-07 Méthode d'exploitation d'un générateur de vapeur à passage unique Expired - Lifetime EP0308728B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3731728 1987-09-21
DE3731728 1987-09-21

Publications (2)

Publication Number Publication Date
EP0308728A1 EP0308728A1 (fr) 1989-03-29
EP0308728B1 true EP0308728B1 (fr) 1991-06-05

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EP88114622A Expired - Lifetime EP0308728B1 (fr) 1987-09-21 1988-09-07 Méthode d'exploitation d'un générateur de vapeur à passage unique

Country Status (4)

Country Link
US (1) US4869210A (fr)
EP (1) EP0308728B1 (fr)
JP (1) JPH01107003A (fr)
DE (1) DE3863153D1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7179871B2 (en) 2000-02-09 2007-02-20 Shell Oil Company Non-symmetrical ligands and catalyst systems thereof for ethylene oligomerization to linear alpha olefins
US9080467B2 (en) 2011-02-25 2015-07-14 Siemens Aktiengesellschaft Method for regulating a brief increase in power of a steam turbine

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EP0439765B1 (fr) * 1990-01-31 1995-05-03 Siemens Aktiengesellschaft Générateur de vapeur
AT394627B (de) * 1990-08-27 1992-05-25 Sgp Va Energie Umwelt Verfahren zum anfahren eines waermetauschersystems zur dampferzeugung sowie waermetauschersystem zur dampferzeugung
DE4142376A1 (de) * 1991-12-20 1993-06-24 Siemens Ag Fossil befeuerter durchlaufdampferzeuger
DE4303613C2 (de) * 1993-02-09 1998-12-17 Steinmueller Gmbh L & C Verfahren zur Erzeugung von Dampf in einem Zwangsdurchlaufdampferzeuger
US5713311A (en) * 1996-02-15 1998-02-03 Foster Wheeler Energy International, Inc. Hybrid steam generating system and method
BE1010594A3 (fr) * 1996-09-02 1998-11-03 Cockerill Mech Ind Sa Procede de conduite d'une chaudiere a circulation forcee et chaudiere pour sa mise en oeuvre.
DE19717158C2 (de) 1997-04-23 1999-11-11 Siemens Ag Durchlaufdampferzeuger und Verfahren zum Anfahren eines Durchlaufdampferzeugers
DE19721854A1 (de) * 1997-05-26 1998-12-03 Asea Brown Boveri Verbesserung des Abscheidegrades von Dampfverunreinigungen in einem Dampf-Wasser-Separator
US6213059B1 (en) * 1999-01-13 2001-04-10 Abb Combustion Engineering Inc. Technique for cooling furnace walls in a multi-component working fluid power generation system
DE19907451A1 (de) * 1999-02-22 2000-08-24 Abb Alstom Power Ch Ag Verfahren zum Anfahren eines Zwangdurchlauf-Abhitzekessels und Vorrichtung zur Durchführung des Verfahrens
US7037988B2 (en) 2000-10-03 2006-05-02 Shell Oil Company Process for the co-oligomerisation of ethylene and alpha olefins
ES2272770T3 (es) 2001-08-01 2007-05-01 Shell Internationale Research Maatschappij B.V. Ligandos y sistemas cataliticos derivados de ellos para oligomerizacion de etileno a alfa-olefinas lineales.
US6675747B1 (en) * 2002-08-22 2004-01-13 Foster Wheeler Energy Corporation System for and method of generating steam for use in oil recovery processes
EP1542797B1 (fr) 2002-09-25 2006-05-31 Shell Internationale Researchmaatschappij B.V. Systemes de catalyseurs destines a l'oligomerisation d'ethylene en olefines alpha lineaires
JP5065886B2 (ja) 2004-03-24 2012-11-07 シエル・インターナシヨナル・リサーチ・マートスハツペイ・ベー・ヴエー 遷移金属錯体
AR049714A1 (es) 2004-07-13 2006-08-30 Shell Int Research Proceso de preparacion de alfa olefinas lineales
EP2065641A3 (fr) * 2007-11-28 2010-06-09 Siemens Aktiengesellschaft Procédé de fonctionnement d'un générateur de vapeur en flux continu, ainsi que générateur de vapeur en flux à sens unique
EP2180251A1 (fr) * 2008-09-09 2010-04-28 Siemens Aktiengesellschaft Générateur de vapeur en continu
EP2182278A1 (fr) * 2008-09-09 2010-05-05 Siemens Aktiengesellschaft Générateur de vapeur en continu
DE102010028720A1 (de) * 2010-05-07 2011-11-10 Siemens Aktiengesellschaft Verfahren zum Betreiben eines Dampferzeugers
US20120012036A1 (en) * 2010-07-15 2012-01-19 Shaw John R Once Through Steam Generator
DE102013215457A1 (de) * 2013-08-06 2015-02-12 Siemens Aktiengesellschaft Durchlaufdampferzeuger in Zweizugkesselbauweise
JP6419888B1 (ja) * 2017-04-28 2018-11-07 三菱日立パワーシステムズ株式会社 発電プラント及びその運転方法
EP3495730B1 (fr) 2017-12-08 2024-01-24 General Electric Technology GmbH Systèmes d'évaporateur à passage unique
EP3495729B1 (fr) * 2017-12-08 2020-11-25 General Electric Technology GmbH Systèmes d'évaporateur à passage unique
EP3495732B1 (fr) 2017-12-08 2024-02-14 General Electric Technology GmbH Systèmes d'évaporateur à passage unique
EP3495731B1 (fr) 2017-12-08 2022-02-16 General Electric Technology GmbH Systèmes d'évaporateur à passage unique

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7179871B2 (en) 2000-02-09 2007-02-20 Shell Oil Company Non-symmetrical ligands and catalyst systems thereof for ethylene oligomerization to linear alpha olefins
US9080467B2 (en) 2011-02-25 2015-07-14 Siemens Aktiengesellschaft Method for regulating a brief increase in power of a steam turbine

Also Published As

Publication number Publication date
US4869210A (en) 1989-09-26
EP0308728A1 (fr) 1989-03-29
JPH01107003A (ja) 1989-04-24
DE3863153D1 (de) 1991-07-11

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