Title of Invention

"INTEDRATED GAS-AND STEAM-TURBINE PLANT"

Abstract The invention relates to a fossil-fuel fired gas-and-steam turbine plant (1) comprising a heat-recovery steam generator (30) connected down-steam of the gas-turbine (2) on an exhaust gas side, the heating surfaces of the heat-recovery steam generator (30) being mounted on a water-steam circuit (24) of the steam turbine (20); a gasification device (132) for gasification of a fossll fuel (B) connected upstream of a combustion chamber (6) of the gas turbine (2), oxygen (O2) being fed to the gasification device (132) from an air-separation device (138), the gas-turbine (2) being assigned with an air-compressor (4), the gasification device (132) having an inlet side receiving therethorugh a partial flow (T) of compressed air from said air-compressor (4). Cooling the partial flow (T) of compressed air, a first heat-exchanger (162) configured as an evaporative cooler is flowably connected on the primary side in an interposed bleed air line (140) thereby interconnecting the air-compressor (4) and the air-separation unit (138) , and in that the secondary side of said first heat exchanger (162) being connected to a water-steam drum (164) to form an evaporation circuit (163) for a flow medium (S).
Full Text Gas- and steam-turbine plant
The invention relates to a-h gas- and steam-turbine plant having a heat-recovery steam generator, which is connected downstream of the gas turbine on the flue-gas side' 'and* whose heating surfaces are connected in the water/steam circuit of the steam turbine, and ^having a gasifier 'for fuel, which gasifier is connected upstream of the combustion chamber of the gas turbine.
A gas- and steam-turbine plant having integrated, 'gasification of fossil fuel normally comprises a jgasifier for the fuel, and this gasifier is connected on the outlet side to the combustion chamber of the gas turbine via a number of components provided for che gas cleaning. In this case, a heat-recovery .steam generator, the heating surfaces of which are connected in the water/steam circuit of the steam turbine, may be connected downstream of the gas turbine oh the flue-gas side. Such a plant has been disclosed, for example, by GB-A 2 234 984.
Furthermore, DE 33 31 152 discloses a method of operating a gas-turbine plant having a fuel-gasification plant, in which method the low-oxygen air collecting in an air-separation unit is admixed to the fuel of medium calorific value delivered to the fuel-gasification plant and the fuel/air mixture of low calorific value is fed to the combustion chamber of the gas-turbine plant. In this case, the compressor of the gas-turbine plant, in addition to supplying the combustion chamber with air, also supplies the air-separation unit with air. It is known from US 4,677,829 and US 4,697,415 to cool compressed air from an air compressor oy means of heat exchangers.
For reliable cleaning of the gasified fossil fuel, a device for removing sulphurous constituents is provided in this plant. A saturator is connected downstream of this device in a feed line, opening into

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the combustion chamber, for the gasified fuel, in which saturator the gasified fuel is loaded with steam in order to reduce the pollutant emission. To this end, the gasified fuel flows through the saturator in counterflow to a water flow, which is directed in a water circuit designated as saturator circuit. For an especially high ¦ efficiency, provision is made for an input of heat from the water/steam circuit into the saturator circuit.
In addition to the fossil fuel, the oxygen required for the gasification of the fuel can also be fed to the gasifier of such a gas- and steam-turbine plant. To obtain this oxygen from air, an air-separation unit connected upstream of the gasifier is normally provided. In this case, a partial flow, also designated as bleed air, of air compressed in an air compressor assigned to the gas turbine may be admitted to the air-separation unit.
As a result of the compression process, the air flowing off from the compressor has a comparatively high temperature level. Cooling of the partial flow, also designated as bleed air, of the compressed air is therefore normally necessary before it enters the air-separation unit. The heat extracted in the process from the bleed air is normally transferred to the saturator circuiiL for the heat recovery and thus for achieving a high plant efficiency. Depending on the operating state of the plant, only residual cooling of the bleed air by means of cooling water before it enters the air-separation unit is then necessary in such a design.
However, such a concept for cooling the bleed air assumes that the heat supply during the air cooling and the heat demand in the saturator circuit are matched to one another in a sufficiently effective manner. Such bleed-air cooling - depending on the integration concept, that is depending on the type of air supply for the air-separation unit and the components used in the process - cannot therefore be used universally and is only reliable to a limited extent in some operating states of the gas™ and steam-turbine plant.

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The object of the invention is therefore to specify a gas- and steam™ turbine plant of the abovementioned type in which, irrespective of the integration concept taken as a basis, reliable cooling of the bleed air, in an especially simple type of construction, is ensured in all operating states.
This object is achieved according to the invention by. virtue of the fact that a heat exchanger, in order to cool the partial flow of compressed air, is connected or. the primary side in a bleed-air lir.e connecting the air compressor to the air-separacion unit, which heat exchanger is connected or. the secondary side to a water/steam drum in order to form an evaporator circulation for a flow medium.
The invention in this case is based or. the idea that, for bleed-air cooling which car. be used irrespective of the integration concept and the fuel to be gasified and is reliable in all operating states, the heat extracted from the bleed air should be capable of being drawn off irrespective of a firmly preset heat demand. The bleed-air cooling should therefore be isolated from the heat supply into the saturator circuit. The bleed air is instead cooled by heat exchange with a flow medium. In this case, for especially high operational, stability in a simple type of construction and for favourable input of the heat extracted from the bleed air into the plant process, evaporation of the flow medium is provided, the ge,a.t exchanger being designed as an intermediate-pressure evaporator.
Tor especially flexible bleed-air cooling which can be adapted to various operating states in a simple manner, a further heat exchanger, designed on t>.e secondary side as an evaporator for a flow medium, is connected downstream of the heat exchanger ir, the air-bleed line, the further heat exchanger being designed as a low-pressure evaporator.
The heat exchanger designed as intermediate-pressure evaporator is expediently connected or. the

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flow-medium side to a heating surface, assigned to an intermediate-pressure stage of the steam turbine, in the heat-recovery steam generator. In an analogous arrangement, the heat exchanger designed as a low-pressure evaporator .may be connected on the flow-medium side to a heating surface, assigned to a low-pressure stage -of¦the steam turbine, in the heat-recovery steam generator. However, the heat exchanger designed as a low-pressure ' evaporator is expediently connected on the flow-medium side to a secondary steam consumer, for example to the gasifier or to a gas-processing system connected downstream of the latter. In such an arrangement, reliable feeding of the secondary consumer with process steam or with heating steam is ensured in an especially simple manner.
In a further advantageous development, the or each heat exchanger is in each case connected on the secondary side to a water/steam drum in order to form an evaporator circulation.
In this case, the evaporator circulation may be designed as a forced circulation. In an especially advantageous development, however, the respective evaporator circulation is designed as a natural circulation, a circulation of the flow medium being ensured by pressure differences occuring during the evaporation process and/or by the geodetic arrangement of evaporator and water/steam drum. In such an arrangement, only a circulating pump of comparatively low rating is required for starting the evaporator circulation. At the same time, the respective water/steam drum is expediently connected to a number of heating surfaces arranged in the heat-recovery steam generator.
An additional heat exchanger is advantageously connected downstream of the heat exchanger in the bleed-air line, which additional heat exchanger is connected on the secondary side to a feedwater tank assigned to the heat-recovery steam generator. With such an arrangement, an especially favourable input of heat into

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the saturator circuit can be achieved, the input of heat being independent of the integration, concept. This is because, in this case, the input of heat into the saturator circuit can be effected via a heat exchanger, through which preheated feedwater extracted from the feedwater tank can flow on the primary side- The feedwater leaving this heat exchanger and cooled down by the input of heat into the saturator circuit can then be fed to the additional heat exchanger connected in the bleed-air line, where it heats up again due to the further cooling of the bleed air. An input of heat into the saturator circuit can therefore be achieved without greater heat losses in the feedwater.
In a further advantageous development, for reliable cooling of the blades of the gas turbine, a cooling-air line branches off from the bleed-air line downstream of the heat exchanger or downstream of the heat exchangers as viewed in the direction of flow of the partial flow, via which cooling-air line a partial quantity of the cooled partial flow can be fed as cooling air to the gas turbine in order to cool the blades.
The advantages achieved with the invention consist in particular in the fact that a flexible adaptation of the gas- and steam-turbine plant to different ixi,t^e.gxation concepts while achieving an especially high plant efficiency is made possible by the cooling of the bleed air in a number of heat exchangers designed as evaporators for a flow medium. In this case, the extraction of heat from the bleed air via the heat exchanger designed as evaporator is independent of the input of heat into the saturator circuit. The gas- and steam-turbine plant can therefore be used in an especially reliable manner even in various operating states. Furthermore, the design of the respective heat exchanqer as an evaporator permits an especially simple supply of secondary consumers with process steax or with heating steam. In particular, the gasifier or a gas-processing component connected downstream of the latter

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is suitable as such a secondary consumer. In this case, on account of the comparatively high storage capacity of the respective evaporator circulation, even fluctuating tapped quantities of process steam or heating steam by the respective secondary consumers do not lead to operational malfunctions.
An exemplary embodiment of the invention is explained in more detail with reference to a drawing, in which the figure schematically shows a gas- arxd steam-turbine plant.
The gas- and steam-turbine plant I according to the figure comprises a gas-turbine plant la and a steam-turbine plant 1b. The gas-turbine plant la comprises a gas turbine 2 -with coupled air compressor 4 and a combustion chamber 6, which is arranged upstream of the gas turbine 2 and is connected to a compressed-air line 8 cf" the compressor 4. The gas turbine 2 ar.d the air compressor 4 as well as a generator 10 sit on a common shaft 12,.
The steam-turbine plant 1b comprises a steam turbine 20f with coupled generator 22 and, ir. a water/steam circuit 24, a condenser 26, arranged downstream of the steam turbine 20, as well as a heat-recovery steam generator 30. The steam turbine 20 consists of a first pressure stage or a high-pressure part 20a and a second pressure stage or an intermediate-pressure part 20b as well as a third pressure stage or a low-pressure part 20c, which drive the generator 22 via a ^common shaft 32.
To feed working medium AM, expanded in the gas turbine 2, or flue gas into the heat-recovery steam generator 30, an exhaust-gas line 34 is connected to an inlet 30a of the heat-recovery steam generator 30. The expanded working medium AM from the gas turbine 2 leaves the heat-recovery steam generator 30 via its cutlet., 30b in the direction of a stack (not shown in ar.y more detail) .
The heat-recovery steam generator 30 comprises a condensate pteheater 40, which can be fed on the inlet

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side with condensate K from the condenser 26 via a condensate line 42, in which a condensate pump unit ,44 is connected. On the outlet side, the condensate preheater 40 is connected via a line 4 5 to a feedwater tank 4,6. In addition, in order to bypass the condensate preheater 40 as and when required, the condensate line 42 may be connected directly to the feedwater tank 46 via a bypass line (not shown). The feedwater tank 46 is connected via a line 47 to a high-pressure feed pump 48 having intermediate-pressure extraction^
The high-pressure feed pump 4 3 brings the feedwater S flowing off from the feedwater' tank The steam outlet 68 of the high-pressure part 20a of the steam turbine 20 is connected via a reheater 70 to the steam inlet 72 of the intermediate-pressure part 20b of the steam turbine 20. The steam outlet 74 of the intermediate-pressure part 20b is connected via an overflow line 76 to the steam inlet 78 of the low-pressure part 20c of the steam turbine 20. The steam outlet 80 of the low-pressure part 20c of the steam turbine ?0 is connected via a steam line 82 to the condenser 26, so that a closed water /steani circuit 24 results.
In addition, a branch line 84 branches off from

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the high-pressure purr.p 4 8 at an extraction point at which the condensate K reaches an intermediate pressure. The branch line 84 is connected via a further feedwater preheater 86 or intermediate-pressure economizer to an intermediate-pressure stage 90, assigned to the intermediate-pressure part 20b of the steam turbine 20, of the wacer/siea^. circuit. To this end/ the second feedwater preheater 36 is connected on the outlet side to an intermediate-pressure drum 36 of the intermediate-pressure stage 90 via a feedwater line 94, which can be shut off with a valve 92. The intermediate-pressure drum 96 is connected to a heating surface 98, arranged in the heat-recovery steam generator 3C and designed as an intermediate-pressure evaporator, in order to fom a water/stearr. circulation IOC. To craw off intermediate-pressure live stesrr. "', the intermediate-pressure drum 96 is connected via a stearr. line 102 to the reheatsr 7 0 and thus to the stearr, ir.let 7 2 of the intermedia te-pressure part 20b of the steam turbine 20.
Branching off from the line 47 is a further line l^C, which is provided with a low-pressure feed purr.p 10", can be shut off with a valve 1C8 and is connected to a low-pressure stage 120, assigned to the low-pressure part 20c of Che steam turbine 20, of the water /stearr. circuit 24. The low-pressure stage 120 comprises a low-pressure drum 122, which is connected to a heating surface 124, arranged in the heat-recovery steam generator 30 and designed as a low-pressure evaporator, in order to fom a water/steam circulation 126. To draw off low-pressure live steam F1', the low-pressure drum 122 is connected to the overflow line 76 via a steam line 128, in which a low-pressure superheater 129 is connected. In the exemplary embodiment, therefore, the water/steam circuit 24 of the gas- ami steam-turbine plant 1 comprises three pressure stages 50, 90, 120. Alternatively, however, fewer, in particular two, pressure stages may be provided.
The gas-turbine plant la is designed for operation with a gasified synthetic gas SG, which is

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produced by the gasification of a fossil fuel B. For example, gasified coal or gasified oil may be provided as the sythetic gas. To this end, the combustion chamber 6 of the gas turbine 2 is connected on the inlet side to a gasifier 132 via a fuel line 13C. Coal or oil, as fossil fuel B, can be fed to the gasifier 132 via a feed system 134.
To provide the oxygen 0j required for the gasification of the fossil fuel 8, an air-separation unit 138 is connected upstream of the gasifier 132 via an oxygen line 136. A partial flow ? \ of the air compressed in the air compressor 4 can be admitted to the air-separation unit 138 on the" inlet side. To this Bnd, the air-separation unit 138 is connected on the inlet side to a bleed-air line 14 0, which branches off fro:?, the compressed-air line 8 at a branch point 142. In accition, a further air line 143.,,.. in which an additional air compressor 144 is connected, opens into the bleed-air line 14 0. In the exemplary embodiment, therefore, the total air flew L flowing to the air-separation unit 138 is composed of the partial flow T branched oxi, from the 'compressed-air line 8 and the air flow delivered by the additional air compressor 14 4. Such a circuit concept is also de.sigr.a.ted as partly integrated .plant concept. In an alternative configuration, the so-cailec fully integrated plant concept, the further air line 143 together with the additional air compressor 144 may also be omitted, so that the feeding of the air-separation unit 138 with air is effected completely via the partial flow T bled from the compressed-air line 8.
The nitrogen N2 obtained in the air-separation unit 138 in addition to the oxygen O2 during the separation of the air flow is fed via a nitrogen line 145 connected to the air-separation unit 138 to a mixing device 146 and is aomixed there to the synthetic gas SG. In this case, the mixing device 14 6 is designed for especially uniform and strand-free mixing of the nitrogen N2 with the synthetic gas SG.
The synthetic gas SG flowing off from the

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gasifier 132 passes via the fuel line 130 first of all into a crude-gas heat-recovery steam generator 14 7, in which the synthetic gas SG is cooled down by heat exchange with a flow medium. In a manner not shown in any more detail, high-pressure steam generated during this heat exchange is fed to the high-pressure stage .50 of the water/steam circuit 24.
As viewed in the direction of flow of the synthetic gas SG, a deduster 148 for the synthetic gas SG and a desulphurization unit 14 9 are connected ir. the fuel line 130 downstream of the crude-gas heat-recovery steam generator 147 and upstream of the mixing device 14 6. In an alternative configuration, instead of the deduster 14 8, in particular during gasification of oil as fuel, a soot scrubber may also be provided.
For an especially low pollutant emission during
the combustion of the gasified fuel in the ccrrJoustion
chamber 6, . provision is made for loading the gasified
fuel with steam before entry into the combustion chamber
6. This may be effected in a saturator system in an
especially advantageous manner from the thermal point of
view. To this end, a saturator 150, in which the
gasified fuel is directed in counterflow to heated
saturator water, is connected in the fuel line 130. In
this case, the saturator water circulates in a saturator
circuit 152, which is connected to the saturator 150 and
in which a circulating pump 154 and, for the preheating
of the saturator water, a heat exchanger 156 are
connected. In this case, preheated feedwater from the
intermediate-pressure stage 90 of the water/stearr,
circuit 24 is admitted to the heat exchanger 156 on the
primary side. To compensate for the losses of saturatcr
water which occur during the saturation of the gasified
fuel, a feeder line 158 is connected to the saturator
circuit 152.
As viewed in the direction of flow of the synthetic gas SG, a heat exchanger 159 acting as crude-gas /pure -gas heat exchanger is connected downstream of the saturator 150 in the fuel line 130 on the secondary

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side. In this case, the heat exchanger 159 is likewise connected in the fuel line 130 or. the primary side at a point upstream of the deduster 14 8, so that the synthetic gas SG flowing to the deduster 148 transfers some of its heat to the synthetic gas SG flowing off from the saturator 150.. The directing of the synthetic gas 3G via the heat exchanger 159 before entry into the desulphurization unit 149 my also be provided m a circuit concept which is modified with regard to the otner components.
Connected between the saturator 150 and the heat exchanger 159 m the fuel line 130 en the secondary side is a further heat exchanger 160, which may be heated en the primary side by feedwater or also by stearr.. In this case, even during different operating states of the gas-and steam-turbine plant 1-, the heat exchanger 159, designed as crude-gas/pure-gas heat exchanger, and the heat exchanger 160 ensure especially reliable preheating of the synthetic gas SG flowing to the combustion, cnamber 6 of the gas turbine 2.
In order to admit steam as and when required to the synthetic gas SG flowing to the combustion chamber 6, a further mixing device 161 is also connected in the fuel line 130, to which mixing device 1*61 intermediate-pressure steam can be fee via a steam line (not shown in any more detail), in particular in order to ensure reliable gas-turbine operation in the event ' of operational malfunctions.
To cool the partial flow T of compressed air to be fed to the air-separation unit 138 and also designated as bleed air, a heat exchanger 162, which is designed on the secondary side as an intermediate-pressure evaporator for a flow medium S', is connected in the bleed-air line 140 on the primary side. In order to form an evaporator circulation 163, the heat exchanger 162 is connected tc a water/steam drum 164 designed as an intermediate-pressure drum. The water/steam drum 164 is connected via lines 166, 168 to the intermediate-oressure drum 96 assigned to the

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water/steam circulation 100. Alternatively, however, the heat exchanger 162 may also be connected on the secondary side directly to the intermediate-pressure drum 96. In the exemplary embodiment, therefore, the water/steam drum 164 is connected indirectly to the heating surface 98 designed as an intermediate-pressure evaporator. In addition, fcr the subsequent feeding of evaporated flow medium S.', a feedwater line 170 is connected to the water/steam drum 164.
As viewed in the direction cf flew of the partial flow T of compressed air^ a further heat exchanger 17.2 is connected downstream cf the heat exchanger 162 in the bleed-air line 140, and this further heat exchanger 172 is designed on the secondary side as a low-pressure evaporator for a flow medium S' In this case, the heat exchanger 172, in order to form an evaporator circulation 174, is connected to a water /steam drum 17 6 designed as a low-pressure drum. In the exemplary embodiment, the water/steam drum 176 is connected via' lines 178, 130 to the low-pressure drum 122 assigned to the water/steam circulation 126 and is therefore indirectly connected to the heating surface 1?4 designed as a low-pressure evaporator. Alternatively, the water/steam drum 176 -may also be connected in another suitable manner, in which case stearr. bled from the water/steam drum 17 6 can be fed to a secondary consumer as process steam and/or as heating steam. In a further alternative configuration, the heat exchanger 172 may also be connected on the secondary side directly to the low-pressure drum 122. In addition, the water/steam drum 176 is connected to a feedwater line 182.
the evaporator circulations 163, 174 may each be designed as forced circulation, the circulation of the flow medium S1 and S' ' respectively being ensured by a circulating pump, and the flow medium S', S1' at least partly evaporating in the heat exchanger 162 or 172 respectively designed as a_Q_e_vaporato.r. In the exemplary embodiment, however, both the evaporator circulation 163

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and the evaporator circulation 17 4 are each designed as natural circulation, the circulation of the flow medium S' or S" respectively being ensured by the pressure differences occurring during the evaporation process and/or by the geodetic arrangement of the respective heat exchanger 162 or 172 and the respective water/steam drum 164 or 176. In this configuration, in each case only a circulating pump (not shown) of comparatively low rating for starting the system is connected in ¦ the evaporator circulation 163 or in the evaporator circulation 174 respectively.
For the input of heat into the saturator circuit 152, a saturator-water heat exchanger 18'4, to which feedwater S can be admitted on the primary side from the feedwater tank 46, is provided in addition to the heat exchanger 156 to which heated feedwater branched off downstream of the feedwater preheater 86 can be admitted. To this end, the saturator-water -heat-exchanger 184, on the primary side, is connected on the inlet side via a line 15-6- to the branch line 84 and on the outlet side via a line 188 'to the feedwater tank 46. To reheat the cooled feedwater s flowing off from the saturator-water heat exchanger 18*4, an additional heat exchanger 190 is connected in the line 188, and this heat exchanger 190 is connected on the primary side downstream of the heat exchanger 172 in the bleed-air line 14 0. Especially high heat recovery from the bleed air and thus an especially high efficiency of the gas-and steam-turbine plant 1 can be achieved by such an
arrangement.
As viewed in the direction of flow of the partial flow T, a cooling-air line 192 branches off from the bleed-air line 140 between the heat exchanger 172 and the heat exchanger 190., via which, cooling-air line 192 a partial quantity T1 of the cooled partial flow T can be fed as cooling air to the gas turbine 2 in order to cool the blades.
Due to the design of the heat exchangers 162 and 172 as intermediate-pressure evaporator and low-pressure

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evaporator respectively, reliable cooling of the bleed air is ensured even during various operating states of the gas- and steam-turbine plant 1 and even in the case of different integration concepts for the gasification of the fossil fuel B. The concept of the bleed-air cooling by connecting the heat exchangers 162 and 172, designed as evaporator coolers, in the bleed-air line 140 is therefore also especially suitable for various fossil fuels B. In particular on account of the multiplicity of adjustable steam parameters in the evaporator circulations 163 and 17 4, such bleed-air cooling can be adapted in an especially flexible manner to various requirements during the operation of the gas-and steam-turbine plant 1.

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WE CLAIM;
1. A fossil-fue! fired gas-and-steam turbine plant (1) comprising a heat-
recovery steam generator (30) connected down-steam of the gas-turbine
(2) on an exhaust gas side, the heating surfaces of the heat-recovery steam
generator (30) being mounted on a water-steam circuit (24) of the steam
turbine (20); a gasification device (132) for gasification of a fossi! fuel (B)
connected upstream of a combustion chamber (6) of the gas turbine (2),
oxygen (O2) being fed to the gasification device (132) from an air-
separation device (138), the gas-turbine (2) being assigned with an air-
compressor (4), the gasification device (132) having an inlet side receiving
therethorugh a partial flow (T) of compressed air from said air-compressor
(4), characterized in that for cooling the partial flow (T) of compressed air,
a first heat-exchanger (162) configured as an evaporative cooler is flow ably
connected on the primary side in an interposed bleed air line (140)
interconnecting the air-compressor (4) and the air-separation unit (138) ,
and in that the secondary side of said first heat exchanger (162) being
connected to a water-steam drum (164) to form an evaporation circuit
(163) for a flow medium (S7).
2. The plant as claimed in claim 1, wherein a second heat exchanger (172),
disposed on the secondary side being configured as an evaporator for a
flow medium (S'), is connected downstream of the first heat exchanger
(162) in the bleed-air line (140), the first heat exchanger (162) being
designed as an intermediate-pressure evaporator and the second heat
exchanger (172) being designed as a low-pressure evaporator.
3. The plant (1) as claimed in claim 1 or 2, wherein the second heat
exchanger (172) is connected on the secondary side to a water/steam drum
(176) in orde to form an evaporator circulation (174).

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4. The plant (i) as claimed in claim 3f wherein one of the water/steam drum
(164, 176} is connected to a plurality of heating surfaces (98,124)
configured in the heat-recovery steam generator (30).
5. The plant (I) as claimed in one of claims i to 4, wherein a third heat
exchanger (190) is connected downstream of the first heat exchanger (162)
in the bleed-air line (40), the third heat exchanger (190) being connected
on ih& secondary side to a feedwater tank (46) assigned to tiie heat-
recovery steam generator (30).
6. The plant (I) as claimed in one of claims i to 5, wherein a cooling-air line
(192) branches off from tfie bleed-air line (140) downstream of the heat
exchangers (162,172) as viewed in the direction of flow of one of the first
and the second partial flow (T), a partial quantity (T*) of the cooled partial
flow (T) can be fed as cooling air to the gas turbine in order to cooi the
blades via said cooling air line (132).
The invention relates to a fossil-fuel fired gas-and-steam turbine plant (1) comprising a heat-recovery steam generator (30) connected down-steam of the gas-turbine (2) on an exhaust gas side, the heating surfaces of the heat-recovery steam generator (30) being mounted on a water-steam circuit (24) of the steam turbine (20); a gasification device (132) for gasification of a fossll fuel (B) connected upstream of a combustion chamber (6) of the gas turbine (2), oxygen (O2) being fed to the gasification device (132) from an air-separation device (138), the gas-turbine (2) being assigned with an air-compressor (4), the gasification device (132) having an inlet side receiving therethorugh a partial flow (T) of compressed air from said air-compressor (4). Cooling the partial flow (T) of compressed air, a first heat-exchanger (162) configured as an evaporative cooler is flowably connected on the primary side in an interposed bleed air line (140) thereby interconnecting the air-compressor (4) and the air-separation unit (138) , and in that the secondary side of said first heat exchanger (162) being connected to a water-steam drum (164) to form an evaporation circuit (163) for a flow medium (S).

Documents:


Patent Number 202533
Indian Patent Application Number IN/PCT/2001/00042/KOL
PG Journal Number 09/2007
Publication Date 02-Mar-2007
Grant Date 02-Mar-2007
Date of Filing 10-Jan-2001
Name of Patentee SIEMENS AKTIENGESELLSCHAFT
Applicant Address WITTELSBACHERPLATZ 2, D-80333 ,MUNCHEN
Inventors:
# Inventor's Name Inventor's Address
1 SCHIFFERS ,ULRICH HOHE WARTE 2, D-91080 SPARDORF,
2 HANNEMANN ,FRANK HOHE WARTE 2, D-91080 SPARDORF
PCT International Classification Number F 01 K 23/06
PCT International Application Number PCT/DE99/02058
PCT International Filing date 2000-07-02
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 19832294.1 1998-07-17 Germany