EP0334935B1 - Gas-steam generating power plant - Google Patents

Gas-steam generating power plant Download PDF

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Publication number
EP0334935B1
EP0334935B1 EP88908952A EP88908952A EP0334935B1 EP 0334935 B1 EP0334935 B1 EP 0334935B1 EP 88908952 A EP88908952 A EP 88908952A EP 88908952 A EP88908952 A EP 88908952A EP 0334935 B1 EP0334935 B1 EP 0334935B1
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EP
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Prior art keywords
steam
gas
combustion chamber
turbine
power plant
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EP88908952A
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German (de)
French (fr)
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EP0334935A1 (en
Inventor
Raimund Croonenbrock
Reinhold Ulrich Pitt
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Hitachi Zosen Inova Steinmueller GmbH
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L&C Steinmueller GmbH
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K21/00—Steam engine plants not otherwise provided for
    • F01K21/04—Steam engine plants not otherwise provided for using mixtures of steam and gas; Plants generating or heating steam by bringing water or steam into direct contact with hot gas
    • F01K21/042—Steam engine plants not otherwise provided for using mixtures of steam and gas; Plants generating or heating steam by bringing water or steam into direct contact with hot gas pure steam being expanded in a motor somewhere in the plant
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K23/00—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids
    • F01K23/02—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled
    • F01K23/06—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle
    • F01K23/061—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle with combustion in a fluidised bed
    • F01K23/062—Plants characterised by more than one engine delivering power external to the plant, the engines being driven by different fluids the engine cycles being thermally coupled combustion heat from one cycle heating the fluid in another cycle with combustion in a fluidised bed the combustion bed being pressurised

Definitions

  • the invention relates to a gas-steam power plant of the type mentioned in the preamble of claim 1.
  • Such a gas-steam power plant is known from FR-E-92 028 and FR-A-1 496 420, in which the majority of the steam generated in the plant, together with the fuel gases, is discharged to the environment; only a small part of the steam released in the turbine is mixed with the water to preheat the feed water.
  • the steam of the steam turbine which is designed without a condensing device, is added to the combustion chamber at a point where, after mixing, the combustion gas and steam have a common temperature of approx. 600 ° C, while the temperature of the combustion gas in front of the mixing point is 1300 ° C.
  • the steam partially expanded in the gas turbine is therefore not heated to the highest possible temperature in the combustion chamber.
  • GB-A-2 087 252 discloses a pressure fluidized bed with a stationary fluidized bed in a gas-steam power plant, in which steam or water is introduced into the fluidized bed to regulate the temperature of the fluidized bed.
  • the steam turbine of the gas-steam power plant is provided with a condensation device and the condensed water is evaporated again.
  • gas-steam power plants with high-pressure steam generators can be equipped with a pressure-charged fluidized bed furnace, with a compressed coal dust furnace, compressed oil or compressed gas furnace.
  • the aim is always to improve the efficiency of gas-steam power plants.
  • This object is achieved in that the steam removed from a condensation steam turbine is input into the combustion chamber at a near-stoichiometric combustion air ratio in the range from 1 to 1.5 of the fuel and is heated there to the highest possible temperature in the combustion chamber.
  • the steam generated in the plant is returned to the combustion chamber as so-called bleed steam, but is heated there to the highest possible temperature in the combustion chamber in order to serve as a working medium for the gas turbine.
  • the steam is heated to a temperature which is substantially above the currently highest possible temperature in the water-steam cycle, which can be 530 ° C, for example.
  • steam is injected into a combustion chamber to which at least one heating surface is assigned, it can be achieved by appropriate design of the size of the heating surface or heating surfaces that the amount of heat transferred to the high-pressure steam is reduced by just as much as the overheating of the directly into the Combustion steam input to the exhaust gas temperature, d. H. the gas turbine fuel gas temperature is to be used.
  • the heating surface can be adapted in a particularly simple manner by adjusting the height of the fluidized bed.
  • the combustion takes place unchanged at the same Near stoichiometric combustion air ratio.
  • the propellant gas mass flow is therefore only increased by the injection steam mass flow, but not by an additional combustion gas flow.
  • the exhaust gas loss after utilizing the energy available in the exhaust gas of the gas turbine is therefore smaller than in the known process.
  • the heating surface can preferably be designed as a wall and / or as a heating surface which is arranged in the combustion chamber.
  • the firebox is designed as a pressure fluidized bed combustion with a stationary fluidized bed.
  • the gas turbine in a manner known per se from DE-OS 35 36 451 has a heat exchanger for heat exchange with the combustion air and / or a heat exchanger for the water-steam cycle and this one Another gas turbine is connected downstream, in which the combustion gas is expanded while performing work.
  • This second turbine is, in turn, preferred and known per se, part of a turbocharger for the combustion air.
  • the steam introduced into the combustion chamber serves at least partially as motive steam for injecting the fuel into the pressure fluidized bed.
  • the steam to be supplied and removed from the turbine is fed to the combustion chamber in at least two pressure stages, z. B. at a turbine system with an intermediate superheater line pressure stage required for intermediate superheating can be taken from the intermediate superheater line, while the lower pressure stage can be taken from a turbine charged with the ZÜ steam.
  • FIG. 1 schematically shows a high pressure steam generator (1), the combustion chamber of which is designed as a pressure-charged fluidized bed (2).
  • the fluidized bed is supplied as coal (K) and for desulfurization CaCO3.
  • a heating surface (3) is assigned to the firebox (2) (it is clear that several heating surfaces in the form of wall heating surfaces and heating surfaces arranged inside the firebox can be provided).
  • the high-pressure steam leaving the heating surface (3) is fed via a line (4) to a steam turbine (5), in which it is expanded to perform work.
  • the steam turbine (5) drives a generator (6).
  • the steam emerging from the steam turbine (5) is condensed in a condenser (7) and by means of pumps (8) and (9) and a feed water tank (10) located between these pumps via a line (11) to the high-pressure steam generator (1) forwarded.
  • Compressed combustion air (L) is fed to the pressure fluidized bed (2) by means of a compressor (12).
  • the combustion exhaust gases from the combustion chamber (2) are fed via a filter (13) to a gas turbine (14) which expands the combustion exhaust gas and from there via a heat exchanger (15) switched on in the line (11) to a chimney (not shown).
  • bleed steam from the turbine (5) is introduced directly into the combustion chamber (2) of the high-pressure steam generator (1).
  • the steam is heated to the highest possible temperature in the firing chamber and, together with the combustion exhaust gas, relaxes in the turbine (14) which drives the compressor (12) and, if appropriate, an additional generator (18).
  • the steam is the turbine (5) z. B. with a temperature of the order of 530 ° C and a pressure of 37 bar.
  • the bleed steam introduced into the combustion chamber via the line (16) can be heated to a temperature of 850 ° C. in the case of a pressure fluidized bed and can be expanded in the gas turbine (14), which improves the efficiency.
  • FIG. 1 For the gas-steam power plant according to FIG. 2 are shown in FIG. 1 used reference numerals, as far as possible. With regard to the circuit of the gas turbine process shown there, reference is expressly made to DE-OS 35 36 451 and DE-Z "Energiespektrum", Jan. 1987, pp. 21-22, the disclosure of which is hereby also made the subject of the disclosure of the present application becomes.
  • a high-pressure turbine (5a) and a low-pressure turbine (5b) are provided in the gas-steam power plant according to FIG. 2.
  • Steam emerging from the high-pressure turbine (5a) is fed via line (20) to a heating surface (21) in the high-pressure steam generator (1), in order to be subjected to reheating there.
  • the reheated steam is fed to the low-pressure turbine via a line (22).
  • steam of a first pressure stage is fed via a cold reheater line (23) to a preheater (24) lying parallel to the heat exchanger (15).
  • a further preheater (25) is located in series with the preheater (24) and is supplied with tapped steam from the turbine (5b) via a bleed line (26).
  • a control valve (27) is in series with the preheaters (24) and (25).
  • the feed water reservoir (10) is heated via a further tap line (28) of the turbine (5b).
  • a line (30) having a throttle valve (29) branches off from the line (23) and is used to supply the high pressure steam generator with motive steam for injecting the coal (K) into the combustion chamber (2). Since for the injection of the fuel in the form of a coal-water mixture, less steam is introduced directly into the combustion chamber (2) than makes sense for the possible increase in efficiency, the combustion chamber is still connected to the system via a tap line (31) Steam turbine (5b) connected, a control valve (32) also being set in line (31).
  • the pressure in the lines (31) and (30) downstream of the rain valves (32) and (29) must be greater than the combustion chamber pressure built up by the compressor (12) in the combustion chamber, and further the pressure in the line (30) is due to injection of fuel must be higher than in line (31).
  • the gas emerging from the gas turbine (14) is fed to the heat exchanger (15) via a combustion air / combustion gas heat exchanger (33) and is subsequently expanded in a further gas turbine (34) which, together with a compressor upstream of the compressor (12) (35) builds a turbocharger.
  • a gas cooler (36) which is preferably also integrated into the water-steam circuit.
  • the steam introduced via line (4) and having a temperature of 530 ° in the steam turbine (5a) is partially expanded and after another reheating to a temperature of 530 ° in the turbine (5b) fully expanded and at a temperature of 30 ° C condensed.
  • the steam removed from the turbine (5a) via line (23, 30) is fed into the combustion chamber (2) in the case of the pressure fluidized bed according to FIG. 2 heated to the highest possible temperature of 850 ° C and together with the combustion gases in the gas turbine relaxed working.
  • This is shown in the (Ts) diagram of the steam turbine process by the dash-dotted line.
  • the gas turbine (14) or the gas turbines (14) and (34) can thus also be evaluated with respect to the steam turbine process as a steam turbine integrated in the gas turbines.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Engine Equipment That Uses Special Cycles (AREA)

Abstract

A gas-steam generating power plant has at least one high-pressure steam generator (1) with a steam circuit, in which heat and flue gases are produced by combustion of a fuel (K) in a pressurized furnace (2), at least one heating surface (3, 21) connected to the furnace and through which heat from the furnace is transferred directly to the steam circuit, at least one steam turbine (5; 5a, 5b) connected downstream to the heating surface (3; 21), and at least one gas turbine (14; 34) connected to the flue gas side of the furnace (2) for work-performing expansion of the flue gases. To improve the efficiency, at least partially expanded steam (16; 30; 31) is withdrawn from the steam turbine (5; 5a, 5b) during quasi-stoichiometric combustion of the fuel (K) in the furnace and an equivalent amount of water is fed (19) into the steam circuit. Said steam is introduced directly into the furnace (2) at a presure higher than that prevailing in the furnace, heated to the highest possible furnace temperature, and then expanded, together with the flue gas, in the gas turbine (14; 34).

Description

Die Erfindung betrifft eine Gas-Dampf-Kraftanlage der im Oberbegriff des Anspruches 1 genannten Art.The invention relates to a gas-steam power plant of the type mentioned in the preamble of claim 1.

Aus der FR-E-92 028 bzw. der FR-A-1 496 420 ist eine solche Gas-Dampf-Kraftanlage bekannt, bei der der überwiegende, in der Anlage erzeugte Dampf, mit samt den Brenngasen an die Umgebung ausgeschleust wird; nur ein geringer Teil des in der Turbine entspannten Dampfes wird zum Vorwärmen des Speisewasser mit dem Wasser vermischt. Der Dampf der ohne Kondensationseinrichtung ausgeführten Dampfturbine wird in den Feuerraum an einer Stelle zugegeben, an der nach der Vermischung eine gemeinsame Temperatur des Verbrennungsgases und des Dampfes von ca. 600° C vorliegt, während die Temperatur des Verbrennungsgases vor der Mischstelle 1300° C beträgt. Der in der Gasturbine teilexpandierte Dampf wird also nicht auf die im Feuerraum höchstmögliche Temperatur erhitzt.Such a gas-steam power plant is known from FR-E-92 028 and FR-A-1 496 420, in which the majority of the steam generated in the plant, together with the fuel gases, is discharged to the environment; only a small part of the steam released in the turbine is mixed with the water to preheat the feed water. The steam of the steam turbine, which is designed without a condensing device, is added to the combustion chamber at a point where, after mixing, the combustion gas and steam have a common temperature of approx. 600 ° C, while the temperature of the combustion gas in front of the mixing point is 1300 ° C. The steam partially expanded in the gas turbine is therefore not heated to the highest possible temperature in the combustion chamber.

Aus der GB-A-2 087 252 ist eine Druckwirbelschicht mit stationärer Wirbelschicht in einer Gas-Dampf-Kraftanlage bekannt, bei der zur Regelung der Temperatur der Wirbelschicht Dampf oder Wasser in die Wirbelschicht eingebracht wird. Die Dampfturbine der Gas-Dampf-Kraftanlage ist mit einer Kondensationseinrichtung versehen und das kondensierte Wasser wird erneut verdampft.GB-A-2 087 252 discloses a pressure fluidized bed with a stationary fluidized bed in a gas-steam power plant, in which steam or water is introduced into the fluidized bed to regulate the temperature of the fluidized bed. The steam turbine of the gas-steam power plant is provided with a condensation device and the condensed water is evaporated again.

Andere Gas-Dampf-Kraftanlagen mit Hochdruckdampferzeuger können mit einer druckaufgeladenen Wirbelschichtfeuerung, mit einer Druckkohlenstaubfeuerung, Drucköl- oder Druckgasfeuerung ausgerüstet sein. Es wird stets angestrebt, den Wirkungsgrad von Gas-Dampf-Kraftanlagen zu verbessern.Other gas-steam power plants with high-pressure steam generators can be equipped with a pressure-charged fluidized bed furnace, with a compressed coal dust furnace, compressed oil or compressed gas furnace. The aim is always to improve the efficiency of gas-steam power plants.

Es ist daher die Aufgabe der vorliegenden Erfindung, bei einer Gas-Dampf-Kraftanlage der im Oberbegriff des Anspruches 1 genannten Art anzugeben, bei dem ohne Auschleusung des überwiegenden Teiles des in der Anlage erzeugten Dampfes ein hoher Wirkungsgrad erzielt wird.It is therefore the object of the present invention to specify in a gas-steam power plant of the type mentioned in the preamble of claim 1, in which a high degree of efficiency is achieved without removing most of the steam generated in the plant.

Diese Aufgabe wird dadurch gelöst, daß der einer Kondensationsdampfturbine entnommene Dampf bei einem nahstöchiometrischen Verbrennungsluft-Verhältnis im Bereich von 1 bis 1,5 des Brennstoffes in den Feuerraum eingegeben wird und dort auf die im Feuerraum höchstmögliche Temperatur erhitzt wird.This object is achieved in that the steam removed from a condensation steam turbine is input into the combustion chamber at a near-stoichiometric combustion air ratio in the range from 1 to 1.5 of the fuel and is heated there to the highest possible temperature in the combustion chamber.

Bei der erfindungsgemäßen Gas-Dampf-Kraftanlage wird nur eine Teilmenge des in der Anlage erzeugten Dampfes als sogenannter Anzapfdampf in den Feuerraum zurückgeführt, dort jedoch auf die im Feuerraum höchstmögliche Temperatur erhitzt, um als Arbeitsmittel für die Gasturbine zu dienen. Bei der Druckwirbelschichtfeuerung mit einer höchstmöglichen Feuerraum temperatur von 850° C wird der Dampf auf eine Temperatur erhitzt, die im wesentlichen über der zur Zeit höchstmöglichen Temperatur im Wasser-Dampf-Kreislauf liegt, die z.B. 530 ° C betragen kann.In the gas-steam power plant according to the invention, only a subset of the steam generated in the plant is returned to the combustion chamber as so-called bleed steam, but is heated there to the highest possible temperature in the combustion chamber in order to serve as a working medium for the gas turbine. In the pressure fluidized bed combustion with a maximum possible combustion chamber temperature of 850 ° C, the steam is heated to a temperature which is substantially above the currently highest possible temperature in the water-steam cycle, which can be 530 ° C, for example.

Bei der erfindungsgemäßen Gas-Dampf-Kraftanlage sorgt die durch die Zuordnung der Heizfläche zum Feuerraum mögliche direkte Wärmeübertragung an den Hochdruckdampf dafür, daß bei nahstöchiometrischer Verbrennung, d. h. im Bereich von n = 1-1,5, vorzugsweise 1-1,4, die Verbrennungstemperatur im Feuerraum und somit die Treibgastemperatur vor der Gasturbine so begrenzt bleiben wie durch das Feuerungssystem (Druckkohlenstaub-Feuerung, Druckwirbelschicht usw.) und die Bauweise der eingesetzten Gasturbine vorgegeben wird. Wird in einen Feuerraum, dem mindestens eine Heizfläche zugeordnet ist, Dampf injiziert, so kann durch entsprechende Auslegung der Größe der Heizfläche oder Heizflächen erreicht werden, daß die an den Hochdruckdampf übertragene Wärmemenge gerade um soviel vermindert wird, wie zu der überhitzung des direkt in den Feuerraum eingegebenen Dampfes auf die Abgastemperatur, d. h. die Treibgastemperatur der Gasturbine, aufzuwenden ist.In the gas-steam power plant according to the invention, the direct heat transfer to the high-pressure steam possible by assigning the heating surface to the combustion chamber ensures that with near-stoichiometric combustion, ie. H. in the range of n = 1-1.5, preferably 1-1.4, the combustion temperature in the combustion chamber and thus the propellant temperature in front of the gas turbine remain as limited as by the combustion system (compressed carbon dust furnace, pressure fluidized bed, etc.) and the design of the ones used Gas turbine is specified. If steam is injected into a combustion chamber to which at least one heating surface is assigned, it can be achieved by appropriate design of the size of the heating surface or heating surfaces that the amount of heat transferred to the high-pressure steam is reduced by just as much as the overheating of the directly into the Combustion steam input to the exhaust gas temperature, d. H. the gas turbine fuel gas temperature is to be used.

Bei Ausbildung des Feuerraums als druckaufgeladene Wirbelschicht kann die Heizflächenanpassung in besonders einfacher Weise durch Anpassung der Wirbelschichthöhe erfolgen.If the combustion chamber is designed as a pressure-charged fluidized bed, the heating surface can be adapted in a particularly simple manner by adjusting the height of the fluidized bed.

Bei der erfindungsgemäßen Gas-Dampf-Kraftanlage erfolgt die Verbrennung unverändert bei gleichem nahstöchiometrischem Verbrennungsluftverhältnis. Bei gleichem Luftmassenstrom wie im Falle ohne Dampfinjektion in den Feuerraum wird daher der Treibgasmassenstrom nur um den Injektionsdampfmassenstrom vergrößert, nicht aber durch einen zusätzlichen Verbrennungsgasstrom. Der Abgasverlust nach Ausnutzung der im Abgas der Gasturbine verfügbaren Energie ist daher kleiner als im bekannten Prozeß.In the gas-steam power plant according to the invention, the combustion takes place unchanged at the same Near stoichiometric combustion air ratio. With the same air mass flow as in the case without steam injection into the combustion chamber, the propellant gas mass flow is therefore only increased by the injection steam mass flow, but not by an additional combustion gas flow. The exhaust gas loss after utilizing the energy available in the exhaust gas of the gas turbine is therefore smaller than in the known process.

Die Heizfläche kann vorzugsweise als Wand- und/oder als Heizfläche ausgebildet sein, die im Feuerraum angeordnet ist.The heating surface can preferably be designed as a wall and / or as a heating surface which is arranged in the combustion chamber.

Es wird weiterhin bevorzugt, daß der Feuerraum als Druck-Wirbelschichtfeuerung mit stationärer Wirbelschicht ausgebildet ist.It is further preferred that the firebox is designed as a pressure fluidized bed combustion with a stationary fluidized bed.

Zur weiteren Ausnutzung der Abwärme ist es von Vorteil, wenn der Gasturbine in an sich aus der-DE-OS 35 36 451 bekannten Art und Weise ein Wärmetauscher für den Wärmetausch zur Verbrennungsluft und/oder ein Wärmetauscher zum Wasser-Dampf-Kreislauf und diesem eine weitere Gasturbine nachgeschaltet ist, in dem das Verbrennungsgas arbeitsleistend weiterexpandiert wird. Diese zweite Turbine ist in wiederum bevorzugter und an sich bekannte Weise Teil eines Turboladers für die Verbrennungsluft.To further utilize the waste heat, it is advantageous if the gas turbine in a manner known per se from DE-OS 35 36 451 has a heat exchanger for heat exchange with the combustion air and / or a heat exchanger for the water-steam cycle and this one Another gas turbine is connected downstream, in which the combustion gas is expanded while performing work. This second turbine is, in turn, preferred and known per se, part of a turbocharger for the combustion air.

Bei der Ausbildung des Feuerraums als Druckwirbelschichtfeuerung wird weiterhin bevorzugt, daß der in den Feuerraum eingeführte Dampf zumindest teilweise als Treibdampf zur Injektion des Brennstoffes in die Druckwirbelschicht dient. Da aber u. U. für die Injektion des Brennstoffes weniger Treibdampf erforderlich ist als für die Wirkungsgradanhebung zugeführt werden kann, ist es weiterhin von Vorteil, daß der dem Feuerraum zuzuführende und aus der Turbine entnommene Dampf dem Feuerraum in mindestens zwei Druckstufen zugeführt wird, wobei z. B. bei einer Turbinenanlage mit einer für eine Zwischenüberhitzung erforderlichen Zwischenüberhitzerleitung Druckstufe aus der Zwischenüberhitzerleitung entnommen werden kann, während die niedrigere Druckstufe aus einer mit dem ZÜ-Dampf beaufschlagten Turbine entnommen werden kann.When designing the combustion chamber as a pressure fluidized bed combustion, it is further preferred that the steam introduced into the combustion chamber serves at least partially as motive steam for injecting the fuel into the pressure fluidized bed. But since u. U. less propellant steam is required for the injection of the fuel than can be supplied for increasing the efficiency, it is furthermore advantageous that the steam to be supplied and removed from the turbine is fed to the combustion chamber in at least two pressure stages, z. B. at a turbine system with an intermediate superheater line pressure stage required for intermediate superheating can be taken from the intermediate superheater line, while the lower pressure stage can be taken from a turbine charged with the ZÜ steam.

Die Erfindung soll nun anhand der beigefügten Figuren genauer erläutert werden. Es zeigt:

  • FIG. 1 ein vereinfachtes Schaltdiagramm zur Erläuterung der erfindungsgemäßen Gas-Dampf-Kraftanlage,
  • FIG. 2 eine Ausführungsform der erfindungsgemäßen Gas-Dampf-Kraftanlage, bei der der Feuerraum des Hochdruck-Dampferzeugers als druckaufgeladene Wirbelschicht ausgebildet ist, und
  • FIG. 3 ein Ts-Diagramm zur Erläuterung der Zustandsänderung für den einen Dampfteilstrom, der bei der Ausführungsform gemäß FIG. 2 in den Feuerraum eingeführt wird.
The invention will now be explained in more detail with reference to the accompanying figures. It shows:
  • FIG. 1 shows a simplified circuit diagram to explain the gas-steam power plant according to the invention,
  • FIG. 2 shows an embodiment of the gas-steam power plant according to the invention, in which the combustion chamber of the high-pressure steam generator is designed as a pressure-charged fluidized bed, and
  • FIG. FIG. 3 shows a Ts diagram for explaining the change in state for the one steam partial flow, which in the embodiment according to FIG. 2 is introduced into the combustion chamber.

In der FIG. 1 ist schematisch ein Hochdruck-Dampferzeuger (1) dargestellt, dessen Feuerraum als druckaufgeladene Wirbelschicht (2) ausgebildet ist. Der Wirbelschicht wird als Brennstoff Kohle (K) und zur Entschwefelung CaCO₃ zugeführt. Dem Feuerraum (2) ist eine Heizfläche (3) zugeordnet (es ist klar, daß mehrere Heizflächen in Form von Wandheizflächen und im Innern des Feuerraums angeordneten Heizflächen vorgesehen sein können). Der die Heizfläche (3) verlassende Hochdruckdampf wird über eine Leitung (4) einer Dampfturbine (5) zugeleitet, in der er arbeitsleistend expandiert wird. Die Dampfturbine (5) treibt einen Generator (6) an. Der aus der Dampfturbine (5) austretende Dampf wird in einem Kondensator (7) kondensiert und mittels Pumpen (8) und (9) und einem zwischen diesen Pumpen liegenden Speisewasserbehälter (10) über eine Leitung (11) dem Hochdruck-Dampferzeuger (1) zugeleitet.In FIG. 1 schematically shows a high pressure steam generator (1), the combustion chamber of which is designed as a pressure-charged fluidized bed (2). The fluidized bed is supplied as coal (K) and for desulfurization CaCO₃. A heating surface (3) is assigned to the firebox (2) (it is clear that several heating surfaces in the form of wall heating surfaces and heating surfaces arranged inside the firebox can be provided). The high-pressure steam leaving the heating surface (3) is fed via a line (4) to a steam turbine (5), in which it is expanded to perform work. The steam turbine (5) drives a generator (6). The steam emerging from the steam turbine (5) is condensed in a condenser (7) and by means of pumps (8) and (9) and a feed water tank (10) located between these pumps via a line (11) to the high-pressure steam generator (1) forwarded.

Der Druckwirbelschicht (2) wird mittels eines Verdichters (12) verdichtete Verbrennungsluft (L) zugeführt. Die Verbrennungsabgase aus dem Feuerraum (2) werden über einen Filter (13) einer das Verbrennungsabgas arbeitsleistend expandierenden Gasturbine (14) zugeleitet und von dieser über einen in die Leitung (11) eingeschalteten Wärmetauscher (15) zu einem nicht dargestellten Kamin abgeführt.Compressed combustion air (L) is fed to the pressure fluidized bed (2) by means of a compressor (12). The combustion exhaust gases from the combustion chamber (2) are fed via a filter (13) to a gas turbine (14) which expands the combustion exhaust gas and from there via a heat exchanger (15) switched on in the line (11) to a chimney (not shown).

Neben dem in den Wasser-Dampf-Kreislauf eingebundenen Wärmetauscher (15) können bei Bedarf in der Leitung (11) noch weitere Wärmetauscher angeordnet sein, die mit Anzapfdampf von der Dampfturbine (5) her beaufschlagbar sind (vgl. FIG. 2).In addition to the heat exchanger (15) integrated in the water-steam circuit, further heat exchangers can be arranged in the line (11) if required, which can be supplied with bleed steam from the steam turbine (5) (see FIG. 2).

Über eine Anzapfleitung (16), in der ein Drosselventil (17) vorgesehen ist, wird Anzapfdampf von der Turbine (5) direkt in den Feuerraum (2) des Hochdruck-Dampferzeugers (1) eingeleitet. Der Dampf wird auf die im Feurraum vorhandene höchstmögliche Temperatur erwärmt und zusammen mit dem Verbrennungsabgas in der Turbine (14) entspannt die den Verdichter (12) und ggf. zusätzlich einen weiteren Generator (18) antreibt.Via a bleed line (16), in which a throttle valve (17) is provided, bleed steam from the turbine (5) is introduced directly into the combustion chamber (2) of the high-pressure steam generator (1). The steam is heated to the highest possible temperature in the firing chamber and, together with the combustion exhaust gas, relaxes in the turbine (14) which drives the compressor (12) and, if appropriate, an additional generator (18).

Der Dampf wird der Turbine (5) z. B. mit einer Temperatur in der Größenordnung von 530° C und einem Druck von 37 bar zugeführt. Der über die Leitung (16) in den Feuerraum eingeführte Anzapfdampf kann jedoch auf eine Temperatur von 850° C im Falle einer Druckwirbelschicht erhitzt werden und in der Gasturbine (14) entspannt werden wodurch der Wirkungsgrad verbessert wird.The steam is the turbine (5) z. B. with a temperature of the order of 530 ° C and a pressure of 37 bar. However, the bleed steam introduced into the combustion chamber via the line (16) can be heated to a temperature of 850 ° C. in the case of a pressure fluidized bed and can be expanded in the gas turbine (14), which improves the efficiency.

Entsprechend der aus dem Wasserdampf-Kreislauf entnommenen Dampfmenge wird vor oder nach Speisewasserbehälter eine entsprechende Speisewassermenge über Leitung (19) fortlaufend zugeführt.Depending on the amount of steam removed from the steam cycle, a corresponding amount of feed water is continuously supplied via line (19) before or after the feed water tank.

Für die Gas-Dampf-Kraftanlage gemäß FIG. 2 werden die in der FIG. 1 benutzten Bezugszeichen übernommen, soweit dies möglich ist. Hinsichtlich der dort gezeigten Schaltung des Gasturbinenprozesses wird ausdrücklich auf die DE-OS 35 36 451 und die DE-Z "Energiespektrum", Jan. 1987, S. 21-22, verwiesen, deren Offenbarung hiermit auch zum Gegenstand der Offenbarung der vorliegenden Anmeldung gemacht wird.For the gas-steam power plant according to FIG. 2 are shown in FIG. 1 used reference numerals, as far as possible. With regard to the circuit of the gas turbine process shown there, reference is expressly made to DE-OS 35 36 451 and DE-Z "Energiespektrum", Jan. 1987, pp. 21-22, the disclosure of which is hereby also made the subject of the disclosure of the present application becomes.

Bei der Gas-Dampf-Kraftanlage gemäß FIG. 2 ist eine Hochdruckturbine (5a) und einer Niederdruckturbine (5b) vorgesehen. Aus der Hochdruckturbine (5a) austretender Dampf wird über Leitung (20) einer Heizfläche (21) im Hochdruckdampferzeuger (1) zugeführt, um dort einer Zwischenüberhitzung unterzogen zu werden. Der zwischenüberhitzte Dampf wird über eine Leitung (22) der Niederdruckturbine zugeführt.In the gas-steam power plant according to FIG. 2, a high-pressure turbine (5a) and a low-pressure turbine (5b) are provided. Steam emerging from the high-pressure turbine (5a) is fed via line (20) to a heating surface (21) in the high-pressure steam generator (1), in order to be subjected to reheating there. The reheated steam is fed to the low-pressure turbine via a line (22).

An der Hochdruckturbine (5a) wird über eine kalte Zwischenüberhitzerleitung (23) Dampf einer ersten Druckstufe einem parallel zum Wärmetauscher (15) liegenden Vorwärmer (24) zugeführt. In Reihe zum Vorwärmer (24) liegt ein weiterer Vorwärmer (25), der über eine Anzapfleitung (26) mit Anzapfdampf von der Turbine (5b) versorgt wird. Mit den Vorwärmern (24) und (25) liegt ein Regelventil (27) in Reihe. Über eine weitere Anzapfleitung (28) der Turbine (5b) wird der Speisewasser-Vorratsbehälter (10) beheizt.At the high-pressure turbine (5a), steam of a first pressure stage is fed via a cold reheater line (23) to a preheater (24) lying parallel to the heat exchanger (15). A further preheater (25) is located in series with the preheater (24) and is supplied with tapped steam from the turbine (5b) via a bleed line (26). A control valve (27) is in series with the preheaters (24) and (25). The feed water reservoir (10) is heated via a further tap line (28) of the turbine (5b).

Von der Leitung (23) zweigt eine ein Drosselventil (29) aufweisende Leitung (30) ab, über die Treibdampf zur Injektion der Kohle (K) in den Feuerraum (2) dem Hochdruck-Dampferzeuger zugeleitet wird. Da für die Injektion des Brennstoffes in Form einer Kohle-Wasser-Mischung weniger Dampf direkt in den Feuerraum (2) eingeführt wird, als für die mögliche Erhöhung des Wirkungsgrades sinnvoll erscheint, ist der Feuerraum über eine Anzapfleitung (31) weiterhin mit der Dampfturbine (5b) verbunden, wobei in der Leitung (31) ebenfalls ein Regelventil (32) eingestellt ist.A line (30) having a throttle valve (29) branches off from the line (23) and is used to supply the high pressure steam generator with motive steam for injecting the coal (K) into the combustion chamber (2). Since for the injection of the fuel in the form of a coal-water mixture, less steam is introduced directly into the combustion chamber (2) than makes sense for the possible increase in efficiency, the combustion chamber is still connected to the system via a tap line (31) Steam turbine (5b) connected, a control valve (32) also being set in line (31).

Der Druck in den Leitungen (31) und (30) stromab der Regenventile (32) und (29) muß größer sein als der durch den Verdichter (12) im Feuerraum aufgebaute Feuerraumdruck, und weiterhin wird der Druck in der Leitung (30) wegen der Injektion des Brennstoffes höher sein als in der Leitung (31).The pressure in the lines (31) and (30) downstream of the rain valves (32) and (29) must be greater than the combustion chamber pressure built up by the compressor (12) in the combustion chamber, and further the pressure in the line (30) is due to injection of fuel must be higher than in line (31).

Weiterhin wird bei der Ausführungsform gemäß FIG. 2 das aus der Gasturbine (14) austretende Gas über einen Verbrennungsluft-Verbrennungsgas-Wärmetauscher (33) dem Wärmetauscher (15) zugeführt und wird nach diesem in einer weiteren Gasturbine (34) nachexpandiert, die zusammen mit einem dem Verdichter (12) vorgeschalteten Verdichter (35) einen Turbolader aufbaut. Zwischen den beiden Verdichtern (35) und (12) ist ein vorzugsweise ebenfalls in den Wasser-Dampf-Kreislauf eingebundener Gaskühler (36) angeordnet.Furthermore, in the embodiment according to FIG. 2, the gas emerging from the gas turbine (14) is fed to the heat exchanger (15) via a combustion air / combustion gas heat exchanger (33) and is subsequently expanded in a further gas turbine (34) which, together with a compressor upstream of the compressor (12) (35) builds a turbocharger. Between the two compressors (35) and (12) there is a gas cooler (36) which is preferably also integrated into the water-steam circuit.

Es kann zweckdienlich sein, der Reihenschaltung aus Verdichter (35) und Kühler (36), dem Wärmetauscher (15) und der Gasturbine (34) jeweils eine vorzugsweise regelbare Bypassleitung zuzuordnen, um verschiedene Betriebszustände besser auffangen zu können.It may be expedient to assign a preferably controllable bypass line to the series connection of compressor (35) and cooler (36), the heat exchanger (15) and the gas turbine (34) in order to be able to better absorb different operating states.

Wie aus der FIG. 3 ersichtlich ist, wird der über Leitung (4) herangeführte und eine Temperatur von 530° aufweisende Dampf in der Dampfturbine (5a) teilentspannt und nach erneuter Zwischenüberhitzung auf eine Temperatur von 530° in der Turbine (5b) voll entspannt und bei einer Temperatur von 30° C kondensiert. Der aus der Turbine (5a) über Leitung (23,30) entnommene Dampf wird in den Feuerraum (2) im Falle der Druckwirbelschicht gemäß FIG. 2 auf die höchstmögliche Temperatur von 850° C erwärmt und zusammen mit den Verbrennungsabgasen in der Gasturbine arbeitsleistend entspannt. Dies ist in dem (Ts)-Diagramm des Dampfturbinenprozesses durch die strichpunktierte Linie dargestellt. Die Gasturbine (14) bzw. die Gasturbinen (14) und (34) können somit bezogen auf den Dampfturbinenprozeß auch als in die Gasturbinen integrierte Dampfturbine gewertet werden.As shown in FIG. 3 can be seen, the steam introduced via line (4) and having a temperature of 530 ° in the steam turbine (5a) is partially expanded and after another reheating to a temperature of 530 ° in the turbine (5b) fully expanded and at a temperature of 30 ° C condensed. The steam removed from the turbine (5a) via line (23, 30) is fed into the combustion chamber (2) in the case of the pressure fluidized bed according to FIG. 2 heated to the highest possible temperature of 850 ° C and together with the combustion gases in the gas turbine relaxed working. This is shown in the (Ts) diagram of the steam turbine process by the dash-dotted line. The gas turbine (14) or the gas turbines (14) and (34) can thus also be evaluated with respect to the steam turbine process as a steam turbine integrated in the gas turbines.

Aus dem Vorstehenden geht hervor, daß mit der erfindungsgemäßen Gas-Dampf-Kraftanlage durch die Anhebung der mittleren Temperatur des Dampfprozesses eine Wirkungsgradverbesserung erreicht werden kann, ohne daß die heute üblichen Bereiche für Frischdampfdruck und/oder -temperatur für Dampfturbinen verlassen werden müssen. Heute hat sich unter Vermeidung der teuren austenitischen Werkstoffe bei den Großturbinen die Frischdampf- und Zwischenüberhitzungstemperatur auf etwa 520 bis 565° C, der Frischdampfdruck auf etwa 160 bis 250 bar eingependelt.From the above it can be seen that with the gas-steam power plant according to the invention an increase in efficiency can be achieved by raising the mean temperature of the steam process without having to leave the ranges for live steam pressure and / or temperature for steam turbines which are common today. Today, avoiding the expensive austenitic materials in the large turbines, the live steam and reheat temperature has settled to around 520 to 565 ° C, the live steam pressure to around 160 to 250 bar.

Claims (8)

  1. A gas-steam-power plant with at least one high-pressure steam generator with a water-steam-circuit, in the pressurized combustion chamber of which heat and flue gases are produced by combustion of a fuel, with at least one heating surface associated to the combustion chamber through which heat from the combustion chamber is directly transferred to the water-steam-circuit, at least one steam turbine connected downstream to the heating surface, and at least one gas turbine connected to the flue gas side of the combustion chamber for expansion of the flue gases, at least partially expanded steam being withdrawn from the steam turbine under make-up feed of a corresponding amount of water into the water-steam-circuit and being introduced directly into the combustion chamber at a pressure higher than that prevailing in the combustion chamber and thereafter being expanded, together with the flue gas, in the gas turbine, characterized in that the steam withdrawn from a condensing turbine (5, 7) is introduced into the combustion chamber (2) with a near stoichiometric combustion air ratio in the range of 1 to 1,5 of the fuel (K) and is there heated to the temperature highest possible in the combustion chamber.
  2. The gas-steam-power plant according to claim 1, characterized in that the heating surface (3; 21) is in the form of a wall heating surface and/or of a heating surface arranged in the combustion chamber (2).
  3. The gas-steam-power plant according to claim 1 or 2, characterized in that the combustion chamber has the form of a pressurized fluidized bed combustion with a stationary fluidized bed.
  4. The gas-steam-power plant according to anyone of the claims 1 to 3, characterized in that a heat exchanger (33) for a heat exchange to the combustion air (2) is connected to the gas turbine (14).
  5. The gas-steam-power plant according to anyone of the claims 1 to 4, characterized in that a heat exchanger to the water-steam-circuit (15) is connected to the gas turbine (14) and a further gas turbine (34), in which the flue gases are further expanded, is connected to said heat exchanger.
  6. The gas-steam-power plant according to anyone of the claims 1 to 5, characterized in that the steam introduced into the combustion chamber (2) serves at least partially as working-steam for the injection of the fuel (K).
  7. The gas-steam-power plant according to anyone of the claims 1 to 6, characterized in that the steam to be introduced into the combustion chamber (2) and being withdrawn from the steam turbine (5) is introduced into the combustion chamber in at leat two pressure stages.
  8. The gas-steam-power plant according to anyone of the claims 1 to 7 with a turbine unit having a reheat line necessary for reheating characterized in that at least part of the steam to be introduced into the combustion chamber (2) is withdrawn from the reheat line (23).
EP88908952A 1987-10-15 1988-10-13 Gas-steam generating power plant Expired - Lifetime EP0334935B1 (en)

Priority Applications (1)

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AT88908952T ATE84600T1 (en) 1987-10-15 1988-10-13 GAS STEAM POWER PLANT.

Applications Claiming Priority (2)

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DE3734959 1987-10-15
DE19873734959 DE3734959A1 (en) 1987-10-15 1987-10-15 GAS STEAM POWER PLANT

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EP0334935B1 true EP0334935B1 (en) 1993-01-13

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Publication number Priority date Publication date Assignee Title
JP2624891B2 (en) * 1990-11-30 1997-06-25 株式会社日立製作所 Pressurized fluidized bed boiler power plant
DE4117192C2 (en) * 1991-05-25 1994-06-23 Saarbergwerke Ag Process for generating energy in a combined gas-steam power plant and plant for carrying out the process
FR2968706A1 (en) * 2010-12-10 2012-06-15 Alstom Technology Ltd STEAM SUPPLY CIRCUIT OF A TURBINE

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Publication number Priority date Publication date Assignee Title
GB935658A (en) * 1959-12-30 1963-09-04 Union Carbide Corp Process for generating steam using a fluidized bed, combustion apparatus
CH456250A (en) * 1966-05-06 1968-05-15 Sulzer Ag Process for the mixed gas and steam operation of a gas turbine system as well as system for carrying out the process
FR1496420A (en) * 1966-10-11 1967-09-29 Sulzer Ag Process for the mixed supply of gas and steam to a gas turbine installation and installation for implementing this process
FR92028E (en) * 1966-12-28 1968-09-13 Sulzer Ag Process for the mixed supply of gas and steam to a gas turbine installation and installation for implementing this process
DE2138664C3 (en) * 1971-07-23 1974-01-24 Gebrueder Sulzer Ag, Winterthur (Schweiz) Gas-steam turbine plant
CH555471A (en) * 1972-09-07 1974-10-31 Sulzer Ag GAS STEAM TURBINE SYSTEM.
SE434883B (en) * 1980-10-15 1984-08-20 Stal Laval Turbin Ab SET TO OPERATE A COMBINED GAS ANTURBIN INSTALLATION AND COMBINED GAS ANTURBIN INSTALLATION FOR USE OF THE SET
DE3536451A1 (en) * 1985-10-12 1987-04-16 Steinmueller Gmbh L & C PRESSURE-CHARGED OPERATING FIRING FOR A STEAM GENERATOR

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WO1989003471A1 (en) 1989-04-20
ATE84600T1 (en) 1993-01-15
EP0334935A1 (en) 1989-10-04
DE3734959A1 (en) 1989-07-13
DE3877557D1 (en) 1993-02-25
DE3734959C2 (en) 1990-05-31

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