JP2001115859A - CAES power generation system - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To cool turbine components during daytime power generation by using cheap electric power at night and without requiring special cooling equipment. SOLUTION: At night, air compressed by a compressor 1 is guided to a heat exchanger 8, where a hot water tank 6 feeds a water pump 7;
Heat is exchanged with the hot water sent in the step (1), and the hot water after the heat exchange is stored in a hot water tank, and the low-temperature compressed air subjected to the heat exchange is stored in the CAES tank (10). During daytime power generation, the air in the CAES tank is heat-exchanged with turbine exhaust gas in the regenerator 14 to extract turbine combustion air, and the hot water in the hot water tank is flashed to steam in the flash tank 13, This is a configuration in which turbine components are cooled as cooling steam.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for compressing compressed air using CAES (Compressed Air Ene
The present invention relates to a CAES power generation system that stores compressed air energy in a tank and uses the compressed air as gas turbine combustion air during daytime power generation.

[0002]

2. Description of the Related Art In a conventional power generation system, a compressor is operated using inexpensive nighttime electric power, compressed air obtained at that time is stored in a CAES tank, and then the compressed air is used during daytime power generation. A CAES power generation system in which a certain turbine combustion air and a fuel are mixed and burned to generate power by a gas turbine is employed.

In the conventional CAES power generation system, air is compressed by a compressor at night, and the compressed air is guided to a heat exchanger, where the heat is exchanged with, for example, room-temperature water. The hot water obtained after the replacement can be discarded as it is in the daytime using, for example, a cooling tower, or the CA stored at night using the hot water stored in the hot water tank.
It is configured to increase the power generation efficiency of the gas turbine by warming the air coming out of the ES tank, or to turn it into steam by warming the air coming out of the CAES tank, and use it to increase the output of the gas turbine or to reduce NOx. I have.

[0004]

However, in the above-described CAES power generation system, during daytime power generation, the blades of the gas turbine and many other components are brought into a high temperature state with the operation of the turbine. Equipment such as cooling air or steam is separately provided for cooling members, and these turbine components are cooled.

As a result, each component including the wings,
Alternatively, in order to cool a plurality of components collectively, a new cooling facility is required, and there is a problem that the whole system becomes complicated.

The present invention has been made in view of the above circumstances, and stores compressed air, heat exchange water, and the like obtained by using inexpensive nighttime electric power, and uses turbine combustion air or special cooling equipment during daytime power generation. It is an object of the present invention to provide a CAES power generation system that is effectively used for cooling turbine components without having the above.

[0007]

Means for Solving the Problems (1) In order to solve the above-mentioned problems, a CAES power generation system according to the present invention uses compressed air and hot water obtained by compressing air with a compressor at night. The energy stored in the CAES tank is exchanged, the compressed air whose temperature has decreased is stored in the CAES tank, and the hot water whose temperature has increased due to heat exchange is stored in the hot water tank. Regenerating means for heating air with exhaust gas from a gas turbine to obtain combustion air for the gas turbine, and cooling steam for evaporating hot water stored in a hot water tank during the daytime power generation to cool components of the gas turbine And evaporating conversion means for outputting the output.

According to the present invention, by taking the above measures, the regenerating means exchanges heat of the compressed air stored in the CAES tank with the exhaust gas of the turbine during nighttime and uses it for turbine combustion air. It can be used effectively for the power generation efficiency of gas turbines and NOx reduction, and the evaporative conversion means evaporates the hot water stored in the hot water tank during nighttime and uses it as cooling steam for gas turbines. Waste heat can be used effectively, and no special cooling equipment is required.

(2) In the present invention, the vaporization conversion means is eliminated from the components of the above (1), and instead, the hot water in the hot water tank is led to the regenerating means, and the compressed air in the CAES tank is converted into the compressed air. If the hot water in the hot water tank is heat-exchanged with the exhaust gas of the turbine, and the air for turbine combustion and the cooling steam for the gas turbine are taken out, the same operation as in the above (1) can be achieved with a simpler configuration. It is possible.

(3) The present invention has a regenerating means and a vaporization converting means as in the above (1), but the hot water in the hot water tank is vaporized by either the regenerating means or the vaporizing converting means. With such a configuration, even if the power generation system is changed to a power generation system that does not require a regenerating unit as necessary, vaporization can be performed using the vaporization conversion unit, and a highly flexible system can be constructed.

No equipment is required.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 is a system diagram showing an embodiment of a CAES power generation system according to the present invention.

The CAES power generation system includes a compressor 1 that compresses air at night to extract high-temperature, high-pressure compressed air, and a gas turbine that rotates using stored energy obtained by heating and expanding the compressed air by the compressor 1. 2 and a power generation facility including a motor / generator 3 and the like, a night energy storage system 4 for storing air / exhaust heat at night using inexpensive night power, and a daytime generation of the energy stored at night. And a storage energy power generation / regeneration system 5 that is sometimes used.

The nighttime energy storage system 4 includes a hot water tank 6 for storing hot water and a water supply pump 7 for supplying room temperature water.
A heat exchanger 8 for exchanging heat between the compressed air from the compressor 1 and hot water supplied from the water supply pump 7; and a day / night air switching valve for switching a flow direction, for example, according to a predetermined day / night time zone. 9 and C for storing the low-temperature compressed air heat-exchanged in the heat exchanger 8 through the air-switching valve 9 during the nighttime.
And an AES tank 10.

The storage energy power generation / regeneration system 5 flashes hot water from the hot water tank 6 into steam to produce steam, and uses the steam to cool the gas turbine cooling steam 11 and NOx.
The low temperature compressed air in the CAES tank 10 obtained through the day and night air switching valve 9 at the time of power generation in the daytime and heat exchange between the low temperature compressed air in the CAES tank 10 and the exhaust gas from the gas turbine 2 is provided. Regenerator 14
And a combustor 15 for mixing and burning the heat-exchanged air and fuel regenerated by the regenerator 14 and supplying the mixed gas to the gas turbine 2.

Reference numeral 16 denotes a valve provided on the outlet side (flash tank side) of the hot water tank 6, and is controlled so as to be opened during daytime power generation in conjunction with the day / night air switching valve 9.

Next, the operation of the above power generation system will be described.

First, at night, the day / night air switching valve 9 is automatically or manually switched for night use, and the output line of the heat exchanger 8 and the CAES tank 10 are connected.

In this state, the ingested air is compressed, for example, at 400 to 500 degrees (° C.) by using the inexpensive nighttime electric power and rotating the compressor 1 using the electric motor / generator 3 as the electric motor. After the compressed air of high temperature and high pressure is obtained, it is introduced into the heat exchanger 8. The heat exchanger 8 exchanges heat with high-pressure and high-temperature compressed air sent from the compressor 1 and room-temperature water sent from the water pump 7, and the heat-exchanged hot water of, for example, about 200 degrees is heated. It is stored in the water tank 6 and used during daytime power generation.

On the other hand, the low-temperature compressed air heat-exchanged in the heat exchanger 8 passes through the day / night air switching valve 9 and passes through the CAE.
It is stored in the S tank 10 and is used during daytime power generation.

During daytime power generation, the day / night air switching valve 9 is similarly switched automatically or manually for daytime use, and the CAES tank 10 and the input line of the regenerator 14 are connected.

In this state, the hot water stored in the hot water tank 6 is guided to the flash tank 13 through the valve 16 and is flashed there. The gas is supplied as gas turbine cooling steam 11 and is used for cooling required turbine components including blades.

The low-temperature compressed air stored in the CAES tank 10 is sent to the regenerator 14 through the day / night air switching valve 9. The regenerator 14 heat-exchanges the low-temperature air with the exhaust gas of, for example, 1000 ° C. or more from the gas turbine 2 to raise the temperature of the low-temperature compressed air.
To supply. Here, the heated turbine combustion air and fuel are mixed and burned, and the gas turbine 2 is rotated, so that the motor / generator 3 is operated as a generator.

Therefore, according to the above-described embodiment, the compressed air obtained by compressing the air with the compressor 1 at night is led to the heat exchanger 8, where the compressed air and the normal-temperature water heat the compressed air. After the heat exchange, the compressed air at a low temperature after the heat exchange and the hot water from the room temperature water after the heat exchange are stored in the CAES tank 10 and the hot water tank 6, respectively.
Since the compressed air in the ES tank 10 exchanges heat with the turbine exhaust gas in the regenerator 14 and is used as combustion air, it contributes to an increase in the output of the gas turbine and eventually to the power generation efficiency. Since the steam is flashed and used as the cooling steam for the gas turbine 2, the necessary components of the turbine 2 can be cooled without the need for a separate cooling facility, thereby eliminating the need for a special cooling facility and reducing the operating cost and the system. The configuration can be simplified,
In addition, by making effective use of the energy generated during the nighttime when the power cost is low, it greatly contributes to energy saving.

(Second Embodiment) FIG. 2 is a system diagram showing another embodiment of the CAES power generation system according to the present invention. In this figure, the same parts as those in FIG. 1 are denoted by the same reference numerals, and the detailed description thereof will be omitted.

In this power generation system, the flash tank 13 shown in FIG. 1 is deleted, and a multifunctional regenerator 21 having the function of the flash tank 13 in addition to the function of the regenerator 14 shown in FIG. It is in.

This multifunctional regenerator 21 is connected to the output line of the hot water tank 6 in addition to the day / night air switching valve 9 as in FIG. 1, and when the day / night air switching valve 9 is switched during the day, the CAES tank 10 is low. The temperature air is exchanged with the exhaust gas of the gas turbine 2 for heat exchange to increase the temperature and is supplied to the combustor 15 as turbine combustion air, while the hot water from the hot water tank 6 is also exchanged with the exhaust gas of the gas turbine 2 for heat exchange. To generate steam and produce NOx
It is configured to be used as turbine cooling steam 11 in addition to reduction steam 12.

Next, the operation of the above system will be described.

At night, the air / air switching valve 9 is switched automatically or manually for night use, and the output line of the heat exchanger 8 and C
An AES tank 10 is connected, the compressor 1 is rotated by using the motor / generator 3 as a motor, high-temperature and high-pressure compressed air is extracted from the compressed air and introduced into the heat exchanger 8. High temperature and high pressure compressed air and water pump 7
Exchanges heat with the normal-temperature water supplied from the water, stores the hot water after the heat exchange in the hot water tank 6, and converts the low-temperature compressed air heat-exchanged in the heat exchanger 8 into a day-night air switching valve. The storage in the CAES tank 10 through the step 9 is the same as that described with reference to FIG.

On the other hand, at the time of daytime power generation, similarly, the day / night air switching valve 9 is switched automatically or manually for daytime, and the CAES tank 10 and the input line of the multifunctional regenerator 21 are connected. The multifunction regenerator 21 also takes in the hot water stored in the hot water tank 6 by opening the hot water 16 in conjunction with it.

Here, the multifunctional regenerator 21 exchanges heat between the low-temperature compressed air stored in the CAES tank 10 and the exhaust gas from the gas turbine 2 to raise the temperature of the low-temperature air, and 15 Here, the heated air and fuel are mixed and burned, and the gas turbine 2 is rotated to operate the motor / generator 3 as a generator.

The multifunctional regenerator 21 is provided with the hot water tank 6.
The hot water stored in the turbine is heat-exchanged with the above-mentioned turbine exhaust gas to vaporize the steam, and the steam is obtained as NOx reducing steam 12 and turbine cooling steam 11, thereby performing NOx reducing combustion, and 2 is used for cooling required components.

Therefore, according to the above-described embodiment, the same effects as those of the first embodiment can be obtained. In addition, the elimination of the flash tank 13 in FIG. As equipment, equipment costs can be realized at low cost, and energy generated at nighttime when power costs are low can be effectively used.

(Third Embodiment) FIG. 3 is a system diagram showing another embodiment of the CAES power generation system according to the present invention. In this figure, the same parts as those in FIG. 1 are denoted by the same reference numerals, and the detailed description thereof will be omitted.

In this power generation system, a flash tank 13 ′ is newly added to the configuration shown in FIG. 2, and the output line of the flash tank 13 ′ is connected to the line of the gas turbine cooling steam 11. This is similarly connected to the line of the gas turbine cooling steam 11 via the function regenerator 21. And flash tank 1
In addition to the direct connection line 31 between the 3 ^' output line and the gas turbine cooling steam 11 line, path switching valves 33 and 34 are installed on the multifunctional regenerator 21 and the intermediate line 32 between the gas turbine cooling steam 11 line, respectively. These path switching valves 3
3 and 34 are selectively opened and closed, for example, and the flash tank 1
In this configuration, steam that has been flushed directly from 3 ^′ or steam that has undergone heat exchange with turbine exhaust gas in the multifunctional regenerator 21 is output to obtain gas turbine cooling steam 11.

Next, the operation of the above system will be described.

At night, after the air / night switching valve 9 is automatically or manually switched for night use, heat exchange between high-temperature and high-pressure compressed air from the compressor 1 and room-temperature water supplied from the water supply pump 7 is performed. Then, the hot water after the heat exchange is stored in the hot water tank 6 and the low-temperature compressed air heat-exchanged in the heat exchanger 8 is passed through the day / night air switching valve 9 to the CAES tank 1.
The storage at 0 is exactly the same as in FIGS.

Next, at the time of daytime power generation, the day / night air switching valve 9 is similarly switched automatically or manually for daytime, and the CAES tank 10 and the input line of the multifunctional regenerator 21 are connected. The multifunctional regenerator 21 exchanges heat between the low-temperature air stored in the CAES tank 10 and the exhaust gas from the gas turbine 2 to raise the temperature of the low-temperature air, and supplies the low-temperature air to the combustor 15. Here, the heated air and fuel are mixed and burned, and the gas turbine 2 is rotated to operate the motor / generator 3 as a generator.

On the other hand, the hot water stored in the hot water tank 6 is guided to the flash tank 13 'through the valve 16, and at this time, the flash tank 13' or the multifunctional regenerator 21 is used.
NOx to the gas turbine 2
It is supplied not only as reduction steam 12 but also as gas turbine cooling steam 11 and is used for cooling required turbine components including blades.

That is, when the path switching valve 33 is opened, the hot water stored in the hot water tank 6 is flushed into steam in the flash tank 13 ′, and NOx is passed through the path switching valve 33.
The hot water stored in the hot water tank 6 is sent to the multifunctional regenerator 21 via the flash tank 13 ′ when the path switching valve 33 is closed, and is used as the reducing steam 12 and the gas turbine cooling steam 11. Here, it is vaporized by heat exchange with the exhaust gas of the gas turbine 2, and is used as the NOx reduction steam 12 and the turbine cooling steam 11 via the path switching valve 34.

Therefore, according to the above-described embodiment, in addition to the same effects as those of the first embodiment, for example, the hot water stored in the hot water tank 6 is usually steamed by the multifunctional regenerator 21. And used as gas turbine cooling steam 11,
For example, when the exhaust gas of the turbine 2 is discarded without being used or used for other functions, the path switching valve 34 is closed, the path switching valve 33 is opened, and the flash tank 13 ′ is opened.
If it is used as gas turbine cooling steam 11, it can be used as it is even when the system of the power generation system is changed. Can be obtained, and the reliability can be further improved.

In the above embodiment, the hot water is always vaporized by the multifunctional regenerator 21. On the contrary, the conversely, the hot water is vaporized by the flash tank 13 '. A mode using the regenerator 21 may be used.

In addition, the present invention is not limited to the above-described embodiment, and can be implemented in various modifications without departing from the gist thereof.

[0045]

As described above, according to the present invention, air, water, and the like obtained by using inexpensive nighttime power are stored, and turbine combustion air and turbine components are cooled during daytime power generation. Therefore, it is possible to cool the necessary components of the turbine without the need for a separate cooling facility, thereby eliminating the need for a special cooling facility, reducing operating costs and simplifying the system configuration, and reducing nighttime costs. The energy obtained by using electric power can be effectively used during daytime power generation, which can greatly contribute to energy saving.

[Brief description of the drawings]

FIG. 1 is a system diagram showing one embodiment of a CAES power generation system according to the present invention.

FIG. 2 is a system diagram showing another embodiment of the CAES power generation system according to the present invention.

FIG. 3 is a system diagram showing another embodiment of the CAES power generation system according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Compressor 2 ... Gas turbine 3 ... Electric motor / generator 4 ... Night energy storage system 5 ... Storage energy generation and regeneration system 6 ... Hot water tank 7 ... Water pump 8 ... Heat exchanger 9 ... Day and night air switching valve 10 ... CAES Tank 13, 13 'Flash tank 14 Regenerator 15 Combustor 21 Multifunctional regenerator 33, 34 Route switching valve

Claims (3)

[Claims] 1. A CAES (Compressed Air Energy Storage System) for obtaining combustion air for a gas turbine during daytime power generation using compressed air obtained by compressing air with a compressor at night.
rage) In a power generation system, heat exchange is performed between compressed air from the compressor and hot water, the compressed air whose temperature has decreased is stored in a CAES tank, and hot water whose temperature has increased due to the heat exchange is hot water. A night energy storage system that stores the compressed air stored in the CAES tank during the daytime power generation with exhaust gas from the gas turbine to obtain the combustion air for the gas turbine; CAE power generation system comprising: evaporating the hot water stored in the hot water tank at the time of power generation to output cooling steam for cooling the components of the gas turbine. . 2. A CAES power generation system for obtaining combustion air for a gas turbine during daytime power generation using compressed air obtained by compressing air with a compressor at night, wherein the compressed air from the compressor and hot water Heat exchange between the above, the compressed air whose temperature has decreased is stored in a CAES tank, and a night energy storage system which stores the hot water whose temperature has increased by the heat exchange in a hot water tank; The compressed air and the hot water stored in the CAES tank and the hot water tank are heated by the exhaust gas of the gas turbine, respectively, to extract the combustion air of the gas turbine and cooling steam for cooling the components of the gas turbine. A CAES power generation system, comprising: a multifunctional regeneration unit. 3. A CAES power generation system for obtaining combustion air for a gas turbine during daytime power generation using compressed air obtained by compressing air with a compressor at night, wherein the compressed air and hot water from the compressor are used. Heat exchange between the above, the compressed air whose temperature has decreased is stored in a CAES tank, and a night energy storage system which stores the hot water whose temperature has increased by the heat exchange in a hot water tank; The compressed air and the hot water stored in the CAES tank and the hot water tank are heated by the exhaust gas of the gas turbine, respectively, to extract the combustion air of the gas turbine and cooling steam for cooling the components of the gas turbine. A multifunctional regenerating unit, a cooling unit that evaporates the hot water stored in the hot water tank during the daytime power generation and cools components of the gas turbine; CAES, comprising: steam conversion means for outputting recycle steam; and cooling steam selection means for selectively supplying cooling steam obtained respectively from the steam conversion means and the multifunctional regeneration means to the gas turbine. Power generation system.