JP2003021301A - Boiler facility, combined cycle gas turbine generating system, combined cycle plant, and water recovering method for facility plant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a means which efficiently performs recovery of both condensed water and exhaust heat and has excellent economic efficiency. SOLUTION: Heat is exchanged between an exhaust gas EG emitted from a boiler 52 and cooling water CW for cooling the exhaust gas EG to recover exhaust heat. A heat exchanger 53 is disposed in an exhaust route ER so as to recover condensed water W from the exhaust gas EG.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a boiler facility, a combined cycle gas turbine power generation facility, a combined cycle plant and a water recovery method for the boiler facility.

[0002]

2. Description of the Related Art As an example of a conventional combined cycle gas turbine power generation facility, the one of Japanese Patent No. 2877098 will be described below with reference to FIG. In this combined cycle gas turbine power generation facility, a compressor 1 that compresses and discharges gas, a combustor 5 to which the gas compressed by the compressor 1 is supplied, and a combustion gas of the combustor 5 are driven. A turbine 2, a generator 3 that is coaxially connected to the turbine 2, and a power transmission end 4 that transmits electricity generated by the generator 3. The exhaust gas 7 from the turbine 2 is exhausted from the stack 8 into the atmosphere. An intake chamber 10 that takes in the intake air 6 supplied to the compressor 1 is connected to the compressor 1. A louver 9 is arranged on the upstream side of the intake chamber 10. An air filter (not shown) is arranged on the compressor 1 side (backward side) of the louver 9. Further, the intake chamber 10 is provided with a spraying device for spraying fine droplets into the intake chamber 10.

According to the configuration described above, the intake air 6
Passes through the louver 9 and reaches the intake chamber 10, where the water tank 1
The water of No. 7 passes through the control valve 15 having a predetermined opening degree, and the water supply means 13
After that, fine droplets are ejected from the spray nozzle 11 into the intake chamber 10. Then, the intake air 6 forms a spray flow containing the droplets, partially evaporates, and the intake air 6 is cooled and then flows into the compressor 1. The droplets contained in the intake air 6 are vaporized inside the compressor 1 to cool the compressed air. The compressed air after the droplets are vaporized in this way is mixed with the fuel in the combustion gas 5 and burned,
It becomes a high temperature and high pressure gas and flows into the turbine 2 to perform work. Mechanical energy is converted into electrical energy by the power generator 3, and power is supplied to the power transmission end 4. Exhaust gas after work 7
Are released from the stack 8 to the atmosphere. Further, in this conventional example, by providing the spraying device, it is possible to obtain the effect that the output can be improved and the thermal efficiency can be improved.

In this prior art example, seven examples are disclosed in relation to the above-mentioned spraying device, of which the third example is disclosed.
The description of the embodiment will be continued below. The feature of this embodiment is that a moisture recovery device 31 is installed in the exhaust portion of the turbine 2 so that the moisture in the exhaust gas is recovered and reused as spray water to be blown into the intake chamber 10. ing. That is, the moisture recovered from the exhaust gas of the turbine 2 by the moisture recovery device 31 is temporarily
After being stored in the water supply tank 17, it passes through the control valve 15 set to a predetermined opening degree, the water supply means 13, and the spray nozzle 1
It is configured to be ejected into the intake chamber 10 as fine droplets from No. 1.

[0005]

By the way, in the conventional example described above, it is difficult to sufficiently collect water in the exhaust gas of the turbine 2 because the water content per volumetric flow rate is small, and thus the heat exchanger. When the water is collected by installing the heat exchanger 32, it is necessary to increase the heat transfer area between the heat transfer portion and the exhaust gas in the heat exchanger 32. Therefore, the heat exchanger 32 to be installed is inevitably large in size, which causes an increase in equipment construction cost and installation area, which is not economical.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide means for efficiently recovering both condensed water and waste heat and having excellent economical efficiency.

[0007]

The present invention adopts the following means in order to solve the above problems. That is, the boiler facility according to claim 1 is a heat exchanger that recovers exhaust heat by exchanging heat between exhaust gas from the boiler and cooling water that cools the exhaust gas, and recovers condensed water from the exhaust gas. Is provided in the exhaust path of the exhaust gas.

According to the boiler equipment of the above-mentioned claim 1,
The exhaust gas discharged from the boiler generally has a higher water content per volumetric flow rate than the exhaust gas from the turbine, so a sufficient amount of condensed water can be generated even with a relatively small heat transfer area. it can. As a result, the heat exchanger itself can be downsized.

According to another aspect of the combined cycle gas turbine power generation facility, a compressor that compresses and discharges supplied air, a combustor that combusts the air and fuel discharged from the compressor, and the combustion. A combined cycle gas turbine power generation facility, comprising: a gas turbine driven by combustion gas of a reactor; and a combined cycle gas turbine power generation facility installed together with the boiler facility according to claim 1, wherein condensed water recovered from the exhaust gas is
A spraying mechanism for spray-mixing the air supplied to the compressor is provided.

According to the combined cycle gas turbine power generation facility of the second aspect, when the condensed water is sprayed and mixed by the spray mechanism with respect to the air supplied to the compressor, the condensed water is passed through the inside of the compressor. Since the condensed water vaporizes and takes heat from the air, the air temperature at the compressor outlet can be lowered. The power of the compressor is equal to the difference in air enthalpy between the compressor inlet and outlet, and the air enthalpy is proportional to the temperature, so when the air temperature at the compressor outlet decreases,
The power required for the compressor can be reduced. Therefore, the output of the turbine increases as the required power of the compressor that causes output loss decreases.

A combined cycle plant according to a third aspect of the present invention includes a compressor for compressing and discharging the supplied air,
A combustor in which air and fuel discharged from the compressor are mixed and combusted, a gas turbine driven by the combustion gas of the combustor, and an exhaust gas boiler that generates steam by using exhaust gas from the gas turbine as a heat source. And a boiler facility according to claim 1, comprising a spray mechanism for spray-mixing the condensed water recovered by the heat exchanger with the air supplied to the compressor. It is characterized by

According to the combined cycle plant of the third aspect, as in the case of the second aspect, the required power of the compressor can be reduced by lowering the air temperature at the compressor outlet. Therefore, the output of the gas turbine increases as the output of the compressor required decreases.

According to a fourth aspect of the present invention, there is provided a water recovery method for a boiler facility, wherein cooling water for cooling the exhaust gas is supplied to a heat exchanger provided in an exhaust passage of the exhaust gas discharged from the boiler, and the cooling water is supplied. It is characterized in that heat is exchanged with the exhaust gas to recover exhaust heat, and condensed water is obtained from the exhaust gas.

According to the water recovery method of the boiler facility described in claim 4, as in the case of the operation of claim 1, since it is a method of obtaining condensed water from the exhaust gas of a boiler having a relatively high water content, Even with a small heat transfer area, a sufficient amount of condensed water can be produced, and the heat exchanger itself can be downsized.

According to a fifth aspect of the present invention, there is provided a boiler facility or a combined cycle gas turbine power generation facility, a combined cycle plant or a water recovery method for a boiler facility, the boiler according to the first aspect or the combined cycle gas turbine power generation facility or the second aspect. The combined cycle plant according to claim 3 or the water recovery method for boiler equipment according to claim 4 is characterized in that the boiler is an LNG boiler that burns liquefied natural gas as fuel in a mixed manner with air.

According to the boiler facility, the combined cycle gas turbine power generation facility, the combined cycle plant, or the water recovery method of the boiler facility of the fifth aspect, the same effects as those of the first to fourth aspects can be obtained.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION A boiler facility, a combined cycle gas turbine power generation facility, a combined cycle plant, and a water recovery method for the boiler facility of the present invention are described below.
Although described below with reference to the drawings, it is needless to say that the present invention is not limited to this.

The combined cycle plant of the present invention comprises a boiler equipment 50 shown in FIG. 1 and a combined cycle gas turbine power generation equipment 100 shown in FIG. In the following description, first, the boiler equipment 50
Will be described, and then the combined cycle gas turbine power generation facility 100 will be described. The circled numbers 1 and 2 in FIGS. 1 and 2 indicate that these figures are connected here.

A boiler facility 50 shown in FIG. 1 is an LNG boiler which uses liquefied natural gas as a fuel and mixes it with air to burn it, and an air preheater 51 for heating air in the atmosphere taken in by an air fan, and the air preheater. LN LN that has been taken in by air after heating from vessel 51
The boiler 52 that mixes and burns with G, the heat exchanger 53 (condensed water and exhaust heat recovery device) that takes in the exhaust gas EG from the boiler 52 and recovers the condensed water W and the exhaust heat, and the recovered exhaust gas EG Exhaust chimney 54 and recovered condensed water W
Water tank 55 for temporarily storing water, condenser 56 for supplying cooling water CW to heat exchanger 53, and condensate pump 5
No. 7 for heating the cooling water CW supplied to the boiler 52 with the extracted steam. 1 feed water heater 58 and No. 1 2 water heater 59 and No. 3 Feed water heater 60 and high-pressure turbine 61 that receives supply of main steam S from the boiler 52 to perform work
Also, it has a schematic configuration including a medium-pressure turbine 62, a low-pressure turbine 63, and a generator 64.

Then, heat is exchanged between the exhaust gas EG from the boiler 52 and the cooling water CW (condensate) for cooling the exhaust gas EG to recover exhaust heat and also to recover condensed water W from the exhaust gas EG. A particular feature is that the heat exchanger 53 is provided in the exhaust path ER of the exhaust gas EG.
With this configuration, the exhaust gas E discharged from the boiler 52
Cooling water CW that cools the exhaust gas EG is supplied to the heat exchanger 53 provided in the G exhaust path ER, and the cooling water CW exchanges heat with the exhaust gas EG to recover exhaust heat. And a method of recovering water and exhaust heat by obtaining condensed water W from the exhaust gas EG.

The operation of the boiler equipment 50 described above will be described below. First, air in the atmosphere is sucked by the air fan and taken into the air preheater 51. Then, in the air preheater 51, the boiler 5
After being heated by the exhaust gas EG from 2 and raising the temperature,
It is sent to the boiler 52. The heated air taken into the boiler 52 is mixed with the liquefied natural gas LNG and burned to become a high-temperature combustion gas. And this combustion gas,
No. 3 Supply water from the feed water heater 60 to heat the main steam S
To generate. The main steam S exits the boiler 52 and is supplied to the high-pressure turbine 61.

On the other hand, the combustion gas used for producing the main steam S is discharged from the boiler 52 as exhaust gas EG. When the discharged exhaust gas EG passes through the air preheater 51, a part of exhaust heat is recovered by heating the air taken in by the air fan (first exhaust heat recovery). Then, the exhaust gas EG after passing through the air preheater 51
Is taken into the heat exchanger 53, which is a device for recovering condensed water and exhaust heat. Then, the heat exchanger 53 simultaneously collects the condensed water W from the supplied exhaust gas and recovers the exhaust heat.

That is, when the exhaust gas EG passes through the heat exchanger 53, the exhaust gas EG flows around the heat transfer pipe (not shown) that is stretched inside, but inside the heat transfer pipe, Since the water supplied from the water pump 57 to the heat exchanger 53 is flowing, this water and the exhaust gas EG exchange heat via the wall surface of the heat transfer pipe. By this heat exchange,
Exhaust heat that could not be recovered in the first exhaust heat recovery is taken into the water in the heat transfer pipe and recovered (second exhaust heat recovery).

At the same time, when the heat transfer pipe is cooled by heat exchange with water, the water contained in the exhaust gas EG is condensed and adheres to the periphery of the heat transfer pipe. It is collected in the tank 55. The condensed water W temporarily stored in the recovered water tank 55 is used, for example, not only as industrial water but also for improving the output and thermal efficiency of the gas turbine 105 in the combined cycle gas turbine facility 100 described later. Of course, the condensed water W can be used for other purposes. On the other hand, the exhaust gas EG after the exhaust heat and the condensed water W are recovered is exhausted from the chimney 54 as combustion exhaust gas.

The above-mentioned cooling water CW supplied to the heat exchanger 53 is cooled by the seawater taken in by the seawater pump, and the steam is condensed in the condenser 56 to become condensate. It is supplied to the heat exchanger 53 by the water pump 57. In addition, the above-described high-pressure turbine 61
After the main steam S supplied to the high-pressure turbine 61 is worked, the main steam S is taken into the boiler 52 again and heated, and then the medium-pressure turbine 62 and the low-pressure turbine 63 work and the generator 64 generates electricity. I do. In this way, the high-pressure turbine 61, the intermediate-pressure turbine 62, and the low-pressure turbine 63
The main steam S after working in No. 2 is the extracted steam shown by the broken line. 3 water heater 60 and No. 3 2 water heater 59 and No. 1 is supplied to the water heater 58,
The heat heats the condensate (supply water) from the heat exchanger 53 toward the boiler 52. Then, the extracted steam after heating is released to the atmosphere.

Next, the description of the combined cycle gas turbine power generation facility 100 will be continued with reference to FIG. The combined cycle gas turbine power generation facility 100 shown in FIG. 2 is connected to an air intake chamber 101 that takes in air from the atmosphere, an intake chamber 102 into which air from the air intake chamber 101 flows, and a downstream side of the intake chamber 102. Compressor 103, a combustor 104 that mixes and burns the fuel F with the compressed air from the compressor 103, and the combustor 10
Gas turbine 10 working with combustion gas from 4
5 and a generator 106, an exhaust gas boiler 107 that recovers exhaust heat from exhaust gas that has finished work, a water spray pump 108 that sprays the condensed water W recovered by the heat exchanger 53 into the intake chamber 102, It has a schematic configuration including a spray nozzle 109 and a spray air supply pipe 110 for extracting spray air from the compressor 103 and supplying the spray nozzle 109 with air.

In the combined cycle gas turbine power generation facility 100, the supplied air is compressed by the compressor 10.
3 is discharged to the combustor 104, and the air and the fuel F are mixed and combusted in the combustor 104. Further, the gas turbine 10 is generated by the combustion gas thus generated.
5 is driven, and is configured to be installed together with the boiler equipment 50. Further, the combined cycle gas turbine power generation facility 100 is configured to mix the condensed water W recovered from the exhaust gas EG into the air supplied to the compressor 103 by the spray nozzle 109 that is a spray mechanism thereof. .

The operation of the combined cycle gas turbine power generation facility 100 described above will be described below. The condensed water W recovered from the exhaust gas EG of the boiler 52 by the heat exchanger 53 of the boiler facility 50 is supplied from the recovered water tank 55 to the spray nozzle 109 by the water spray pump 108. Then, the fine droplets ejected from the atomizing nozzle 109 into the intake chamber 102 are
The air taken in from the air intake chamber 101 is spray-mixed. The air containing moisture is compressed by the compressor 103.
(AC) takes in and receives compression, but the compressor 103
Since the water content is completely vaporized before reaching the outlet, the air temperature at the outlet of the compressor 103 is lowered.

That is, when passing through the compressor 103, the moisture (condensed water W) is vaporized and takes heat from the air, so that the air temperature at the outlet of the compressor 103 can be lowered.
The power of the compressor 103 is equal to the difference in air enthalpy between the inlet and outlet of the compressor 103, and the air enthalpy is proportional to the temperature. Therefore, when the air temperature at the outlet of the compressor 103 decreases, the required power of the compressor 103 is reduced. Can be reduced. Therefore, the output of the gas turbine 105 increases as much as the required power of the compressor 103 that causes output loss decreases.

The compressed air that has passed through the compressor 103 is mixed with the fuel F in the combustor 104 (CC) and combusted to form high temperature combustion gas. The combustion gas is supplied to the gas turbine 105 to perform work (drive the generator 106 to generate electricity), and then passes through the exhaust gas boiler 107 to recover exhaust heat. That is, for example, the gas turbine 105
Exhaust gas EG from the engine is used as a heat source to generate steam, and this steam drives a steam turbine (not shown) to recover exhaust heat. Then, the exhaust gas EG after passing through the exhaust gas boiler 107 is discharged through the chimney 54 shown in FIG. When the condensed water is sprayed from the injection nozzle 109 into the intake chamber 102, a part of the compressed air is extracted from the air compressor 103 and used.

According to the boiler equipment 50 and its water recovery method of the present embodiment described above, the heat exchanger 53 for recovering exhaust heat and condensed water is provided in the exhaust path ER of the exhaust gas EG from the boiler 52. Adopted the configuration. According to this configuration, the exhaust gas EG discharged from the boiler 52 generally has a higher water content per volumetric flow rate as compared with the exhaust gas EG from the gas turbine 105, so that even with a relatively small heat transfer area. A sufficient amount of condensed water W can be produced. As a result, the heat exchanger 53 itself can be downsized, and the construction cost and installation area of the equipment can be reduced. Therefore, not only can the condensed water W and the exhaust heat be efficiently recovered,
It is possible to provide the boiler facility 50 which is also excellent in economic efficiency.

Further, according to the combined cycle gas turbine power generation facility 100 of the combined cycle plant of the present embodiment, the condensed water W recovered from the exhaust gas EG of the boiler 52 is supplied to the air supplied into the compressor 103. By performing spray mixing with the spray nozzle 109, it is possible to improve the output and thermal efficiency of the gas turbine 105. Further, due to the heat recovery in the heat exchanger 53, No. 1 Since the temperature of the water W at the inlet of the feed water heater 58 rises, the amount of extracted steam from the high-pressure turbine 61, the intermediate-pressure turbine 62, and the low-pressure turbine 63 can be reduced, and the output of the gas turbine 105 can be increased. ing.

[0033]

According to the boiler equipment of the first aspect of the present invention, the heat exchanger for recovering the exhaust heat and the condensed water is provided in the exhaust passage of the exhaust gas from the boiler.
According to this configuration, the exhaust gas discharged from the boiler is
In general, the water content per volumetric flow rate is higher than that of the exhaust gas from the turbine, so that a sufficient amount of condensed water can be generated even with a relatively small heat transfer area. As a result, the heat exchanger itself can be downsized, so that the construction cost of the equipment and the installation area can be reduced. Further, since the exhaust heat recovered by the heat exchanger can be supplied to the water supply to the water supply heater provided in the boiler equipment, in such a case, the inlet temperature of the water supply flowing into the water supply heater is increased. Thus, the amount of steam extracted from the feed water heater can be reduced, and the output of the gas turbine provided in the boiler facility can be increased. Therefore, it is possible not only to efficiently recover both the condensed water and the exhaust heat, but also to provide a boiler facility excellent in economic efficiency.

Further, according to the combined cycle gas turbine power generation facility of the second aspect, the condensed water recovered from the exhaust gas of the boiler is spray-mixed with the air supplied into the compressor by the spray mechanism. It is possible to improve the output and thermal efficiency of the turbine.

Further, according to the combined cycle plant of the third aspect, similarly to the effect of the second aspect, the condensed water recovered from the exhaust gas of the boiler is sprayed to the air supplied into the compressor. By spray mixing, it is possible to improve the output and thermal efficiency of the gas turbine.

Further, according to the method for recovering water of boiler equipment according to the fourth aspect, the heat exchanger itself can be downsized, similarly to the effect of the first aspect, so that the construction cost and installation of the equipment can be reduced. You will be able to get a reduction in area. Therefore, not only the condensed water and the exhaust heat can be efficiently recovered, but also the economy can be improved.

According to the boiler facility, the combined cycle gas turbine power generation facility, the combined cycle plant or the water recovery method of the boiler facility of the fifth aspect, it is possible to obtain the same effects as those of the first to fourth aspects. .

[Brief description of drawings]

FIG. 1 is a schematic device configuration diagram showing an embodiment of a boiler facility of a combined cycle plant of the present invention.

FIG. 2 is a schematic device configuration diagram of a combined cycle gas turbine power generation facility that is combined with the boiler facility to form a combined cycle plant.

FIG. 3 is a schematic device configuration diagram showing an example of a conventional combined cycle gas turbine power generation facility.

[Explanation of symbols]

50 ... Boiler equipment 52 ... Boiler, LNG boiler 53 ... Heat exchanger 100: Combined cycle gas turbine power generation facility 103 ... Compressor 104 ... Combustor 105 ... Gas turbine 107 ... Exhaust gas boiler 109 ... Spray nozzle (spray mechanism) CW: cooling water EG: Exhaust gas ER: Exhaust route F ... Fuel W: condensed water

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI Theme Coat (Reference) F02C 7/143 F02C 7/143

Claims (5)

[Claims] 1. A heat exchanger for exchanging heat between exhaust gas from a boiler and cooling water for cooling the exhaust gas to recover exhaust heat and to recover condensed water from the exhaust gas, Boiler equipment characterized by being installed in the exhaust path. 2. A compressor for compressing and discharging the supplied air, a combustor for combusting the air and fuel discharged from the compressor, and a gas turbine driven by the combustion gas of the combustor. A combined cycle gas turbine power generation facility provided with the boiler facility according to claim 1, wherein the condensed water recovered from the exhaust gas is spray-mixed with the air supplied to the compressor. A combined cycle gas turbine power generation facility characterized by having a mechanism. 3. A compressor for compressing and discharging the supplied air, a combustor in which the air and fuel discharged from the compressor are mixed and combusted, and a gas driven by the combustion gas of the combustor. A combined cycle plant comprising a turbine, an exhaust gas boiler for generating steam using exhaust gas from the gas turbine as a heat source, and the boiler facility according to claim 1, wherein condensed water recovered by the heat exchanger is A combined cycle plant, comprising a spraying mechanism for spray-mixing the air supplied to the compressor. 4. Cooling water for cooling the exhaust gas is supplied to a heat exchanger provided in an exhaust path of the exhaust gas discharged from the boiler, and the cooling water exchanges heat with the exhaust gas. A method for recovering water in a boiler facility, which comprises recovering exhaust heat and obtaining condensed water from the exhaust gas. 5. The boiler according to claim 1, or the combined cycle gas turbine power generation facility according to claim 2, wherein the boiler is an LNG boiler that uses liquefied natural gas as a fuel to mix and burn with air. The combined cycle plant according to claim 3 or claim 4.
Water recovery method for the described boiler equipment.