CN114776393A - An air energy storage power generation system and method coupled with thermal power - Google Patents

Abstract

The invention provides an air energy storage power generation system and method coupled with thermal power, wherein the power generation system comprises thermal power equipment and air energy storage power generation equipment, the thermal power equipment comprises a boiler, a high-pressure heater and a deaerator, and the air energy storage power generation equipment comprises a steam-air heat exchanger and an air turbine; the steam-air heat exchanger and the air turbine are at least provided with two stages and are alternately connected in series, and a steam side inlet of the steam-air heat exchanger is connected with a branch pipeline of boiler steam. According to the invention, thermal power equipment and air energy storage equipment are coupled, especially, a boiler steam part is extracted for air turbine power generation, and the temperature of compressed air is increased, so that the power generation capacity of an air energy storage system is improved; the pressure matching of each stage of extraction steam and compressed air is good, which is beneficial to reducing the pressure difference and the wall thickness of two sides of the heat exchange tube, thereby reducing the material consumption and the processing difficulty; the steam side of the steam-air heat exchanger is used for phase change heat exchange, the heat exchange coefficient is high, the size of the heat exchanger can be reduced, and the cost is reduced.

Description

An air energy storage power generation system and method coupled with thermal power

technical field

The invention belongs to the technical field of energy storage, and relates to an air energy storage power generation system and method coupled with thermal power.

Background technique

Under the current new situation of carbon peaking and carbon neutrality, energy storage technology, as an important technology and basic equipment to support new power systems, its large-scale development has become an inevitable trend. Air liquefied energy storage and compressed air energy storage system is an energy storage technology that can realize large-capacity and long-term electrical energy storage. It has the advantages of reliability, economy and environmental protection. It is mainly used in power system to balance load and store renewable energy. , system backup, etc., are technologies with great development potential in the field of energy storage. Before large-scale energy storage is popularized and matured, thermal power is still the main force to undertake the task of peak regulation and play an important role in stabilizing the power system. The coupling of compressed air energy storage and liquefied air energy storage with thermal power is gradually popularizing energy storage applications. one of the possible paths.

At present, for the charging and discharging process of the energy storage system, the thermal power steam-water system is coupled with the compression subsystem of the energy storage system during the charging process, and the air compression heat is used to heat the feed water, so as to realize the transfer of part of the energy of the steam-water thermodynamic cycle of the thermal power unit. It is beneficial to improve the peak regulation and frequency regulation ability of thermal power units to participate in the power grid; in the discharge process, the research on air power generation with thermal power coupled compressed air energy storage or liquefied air energy storage generally uses the waste heat of flue gas. The turbine inlet temperature parameter is low, the heat exchange effect is poor, and the investment cost of the required equipment is high.

CN 111764970A discloses a coal-fired thermal power unit system coupled with a compressed air energy storage device and an operation method thereof, including a high-pressure cylinder of a steam turbine of a coal-fired unit, and an air compressor is coupled to the front side of the high-pressure cylinder of the steam turbine through a first coupling; An air filter screen is installed in front of the inlet of the air compressor; the outlet of the air compressor is connected to the compressed air chamber through a compressed air inlet regulating valve; the compressed air chamber is provided with three outlets, one of which passes through the first air turbine inlet The regulating valve is connected with the first air turbine, one way is connected with the second air turbine through the second air turbine inlet control valve, and the other is connected with the factory air through the factory compressed air regulating valve, so as to provide the air source for the factory air; The first air turbine is coaxially connected to the generator, the second air turbine is connected to the small steam turbine through the second coupling, and is coaxially arranged with the feed water pump. The system only specifies the coupling of the compressed air energy storage device to the thermal power unit system, but does not specify the heat exchange process in the air compression and air turbine stages, nor does it mention the connection relationship of the heat exchange system.

CN 113279829A discloses a system and method for coupling compressed air energy storage and thermal power generation. Air is divided into multi-stage low pressure ratio compression and medium pressure ratio compression during the compression process, and the compression process produces two qualities of low temperature and medium temperature. The two types of heat of compression are extracted and stored by using low temperature heat storage working fluid and medium temperature heat storage working fluid respectively, and are used in cascade according to their temperature grades. The compressed air energy storage system mainly involves the charging process of air compression and utilizes the heat of compression, but the discharge process in the energy storage system, that is, the discharge process that does external work, is not specified. The connection is also not clear.

To sum up, for the structure of the air energy storage system coupled with thermal power, especially the connection relationship of the power generation system in the discharge stage, it is also necessary to select appropriate coupling and connection equipment and parameters according to the actual situation of the compressed air and air turbine, so as to improve the Power generation capacity and energy utilization of air energy storage systems while reducing equipment costs.

SUMMARY OF THE INVENTION

Aiming at the problems existing in the prior art, the purpose of the present invention is to provide an air energy storage power generation system and method for coupling thermal power. It is used for the heating of compressed air in the air energy storage system, thereby improving the parameters of the air turbine before expansion, improving the power generation capacity of the air turbine and the comprehensive utilization rate of the system energy; at the same time, the matching between the steam pressure and the compressed air is better, It helps to balance the pressure on both sides of the heat exchanger, reduce the pressure difference between the inside and outside and the design wall thickness, and reduce the equipment cost.

For this purpose, the present invention adopts the following technical solutions:

In one aspect, the present invention provides an air energy storage power generation system coupled with thermal power, the power generation system includes thermal power equipment and air energy storage power generation equipment, the thermal power equipment includes a boiler, a high-pressure heater and a deaerator, the air Energy storage power generation equipment includes steam-air heat exchangers and air turbines;

The outlet steam of the boiler is divided into each branch steam pipeline and is connected to the heat source inlet of the high pressure heater and the deaerator, the liquid phase outlet of the deaerator is connected to the cold source inlet of the high pressure heater, and the high pressure heater The cold source outlet of the boiler is connected to the water inlet of the boiler;

The steam-air heat exchanger and the air turbine are provided with at least two stages. The steam-air heat exchanger and the air turbine are alternately arranged in series. The branch pipes are connected, and the air-side inlet of the steam-air heat exchanger is the compressed air generated by the air energy storage process.

In the present invention, according to the needs of the air energy storage power generation system, it is coupled with the steam-water system of the thermal power plant, and according to the selection of the thermal power equipment, a part of the boiler steam used for heating by the high-pressure heater is extracted for the air permeation system of the air energy storage system. The flat power generation unit uses the characteristics of high steam temperature to improve the temperature of the compressed air before each section of the air turbine is expanded, thereby improving the power generation capacity of the air turbine and the comprehensive energy utilization rate of the air energy storage system; The pressure of the extraction steam at all levels of the steam-water system of the power plant has a good match with the pressure of the corresponding compressed air during heat exchange, so that the pressure inside and outside the heat exchange tube is balanced and the pressure difference is small, thereby reducing the design wall thickness of the heat exchange tube and reducing The amount of heat exchanger materials and the difficulty of processing; while the heat exchange between steam and air is used, the steam side is phase-change heat, and the heat exchange coefficient is high, which can reduce the heat exchange area, reduce the volume of the heat exchanger, and reduce equipment costs.

The following are the preferred technical solutions of the present invention, but not as limitations of the technical solutions provided by the present invention. Through the following technical solutions, the technical purpose and beneficial effects of the present invention can be better achieved and realized.

As a preferred technical solution of the present invention, the high-pressure heater includes at least two stages, such as two stages, three stages or four stages, etc., preferably three stages.

Preferably, the high-pressure heater includes a first high-pressure heater, a second high-pressure heater and a third high-pressure heater connected in series in sequence, and the liquid phase outlet of the deaerator is connected to the cold source inlet of the third high-pressure heater , the cold source outlet of the first high-pressure heater is connected to the water inlet of the boiler.

As a preferred technical solution of the present invention, the steam pipelines connected to the high-pressure heaters at all levels are arranged in parallel, and all lead out from the outlet steam pipeline of the boiler.

Preferably, the heat source outlet of the high-pressure heaters of each stage is connected with the water inlet of the deaerator through a drain pipe.

As a preferred technical solution of the present invention, the steam-air heat exchanger and the air permeability are provided with four stages on average, and the steam-air heat exchanger sequentially includes a first steam-air heat exchanger and a second steam-air heat exchanger. a heat exchanger, a third steam-air heat exchanger, and a fourth steam-air heat exchanger, the air turbines sequentially include a first air turbine, a second air turbine, a third air turbine, and a fourth air turbine ;

Preferably, the air-side inlet of the first steam-air heat exchanger is connected with compressed air, the air-side outlet of the first steam-air heat exchanger is connected with the inlet of the first air turbine, and the first The outlet of the air turbine is connected to the air side inlet of the second steam-air heat exchanger, and then alternately connected to the air turbine and the steam-air heat exchanger, and the outlet of the fourth air turbine is connected to the atmosphere.

As a preferred technical solution of the present invention, the steam side inlet of each stage of the steam-air heat exchanger is connected to a branch pipeline of boiler steam, and each branch pipeline is arranged in parallel.

Preferably, the branch pipe of the first steam-air heat exchanger is led out from the steam pipe connected to the first high-pressure heater, and the branch pipe of the second steam-air heat exchanger is connected by the second high-pressure heater. The steam pipeline is led out, the branch pipe of the third steam-air heat exchanger is led out by the steam pipeline connected with the third high pressure heater, and the branch pipe of the fourth steam-air heat exchanger is connected by the deaerator Out of the steam line.

Preferably, the heat source outlet of the steam-air heat exchanger is connected with the drain pipe of the corresponding high pressure heater, and finally connected to the deaerator.

On the other hand, the present invention provides a method for using the above system for air energy storage to generate electricity, the method comprising the following steps:

After coupling the air energy storage power generation equipment and the thermal power equipment, the boiler steam is used as the heat source of the compressed air, and the heated compressed air enters the air turbine to generate electricity, and then the steam heating and the air turbine power generation are alternated until the last stage of air is passed. Discharge after turbine.

As a preferred technical solution of the present invention, the outlet steam of the boiler in the thermal power equipment passes through the cylinder and the pipeline, and the steam pressure gradually decreases.

Preferably, different steam pipelines are drawn from different positions of the cylinder, and the corresponding steam pressures are different, as heat sources for different high-pressure heaters and steam-air heat exchangers.

As a preferred technical solution of the present invention, the steam pressure in the steam pipeline connected to the first steam-air heat exchanger is 3.19-6.38MPa, such as 3.19MPa, 3.5MPa, 4.0MPa, 4.78MPa, 5.5MPa, 6.0MPa Or 6.38MPa, etc., but not limited to the listed numerical values, and other unlisted numerical values within the numerical range are also applicable.

Preferably, the steam pressure in the steam pipeline connected to the second steam-air heat exchanger is 1.89-3.79MPa, such as 1.89MPa, 2.1MPa, 2.4MPa, 2.84MPa, 3.2MPa, 3.5MPa or 3.79MPa, etc., However, it is not limited to the recited numerical values, and other unrecited numerical values within the numerical range are equally applicable.

Preferably, the steam pressure in the steam pipeline connected to the third steam-air heat exchanger is 0.88-1.75MPa, such as 0.88MPa, 1.0MPa, 1.2MPa, 1.32MPa, 1.5MPa or 1.75MPa, etc., but not only Limitation to the recited values applies equally to other non-recited values within the range of values.

Preferably, the steam pressure in the steam pipeline connected to the fourth steam-air heat exchanger is 0.45-0.89MPa, such as 0.45MPa, 0.54MPa, 0.60MPa, 0.675MPa, 0.75MPa, 0.82MPa or 0.89MPa, etc., However, it is not limited to the recited numerical values, and other unrecited numerical values within the numerical range are equally applicable.

As a preferred technical solution of the present invention, the initial pressure of the compressed air is 6-12 MPa, such as 6 MPa, 7 MPa, 8 MPa, 9 MPa, 10 MPa, 11 MPa or 12 MPa, etc., and the temperature is 10-110 ℃, such as 10 ℃, 30 ℃, 50°C, 60°C, 80°C, 100°C, or 110°C, etc., but are not limited to the recited numerical values, and other unrecited values within the respective numerical ranges are also applicable.

In the present invention, since the air energy storage system usually includes a charging unit and a discharging unit, and the air energy storage power generation equipment in the present invention is the discharging unit, which uses the compressed gas to expand in the air turbine to generate power, and the source of the compressed gas Usually a charging unit.

Preferably, the compressed air is heated through a steam-air heat exchanger, then expanded through an air turbine to generate electricity, with a lower temperature and pressure, and then alternately enters the steam-air heat exchanger and the air turbine.

As a preferred technical solution of the present invention, the temperature of the compressed air after passing through the first steam-air heat exchanger is 220-280 °C, such as 220 °C, 240 °C, 250 °C, 260 °C or 280 °C, etc. After the air turbine, the pressure is 1.65 to 3.3 MPa, such as 1.65 MPa, 2.0 MPa, 2.2 MPa, 2.47 MPa, 2.8 MPa, 3.0 MPa or 3.3 MPa, etc., but it is not limited to the listed values, and other values are within the respective value ranges. The same applies to non-recited values.

Preferably, the temperature of the compressed air after passing through the second steam-air heat exchanger is 200-240 °C, such as 200 °C, 210 °C, 220 °C, 230 °C or 240 °C, etc., and then after passing through the second air turbine, The pressure is 0.45 to 0.9 MPa, such as 0.45 MPa, 0.5 MPa, 0.6 MPa, 0.675 MPa, 0.75 MPa, 0.85 MPa or 0.9 MPa, etc., but not limited to the listed values, and other unlisted values within the respective numerical ranges are the same Be applicable.

Preferably, the temperature of the compressed air after passing through the third steam-air heat exchanger is 170-210 °C, such as 170 °C, 180 °C, 190 °C, 200 °C or 210 °C, etc., and then after passing through the third air turbine, The pressure is 0.13-0.26MPa, such as 0.13MPa, 0.15MPa, 0.18MPa, 0.195MPa, 0.22MPa, 0.24MPa or 0.26MPa, etc., but not limited to the listed values, and other values not listed within the respective numerical ranges are the same Be applicable.

Preferably, the temperature of the compressed air after passing through the fourth steam-air heat exchanger is 140-180°C, such as 140°C, 150°C, 160°C, 170°C or 180°C, etc., but not limited to the listed values, Other unlisted values within this value range are also applicable; after passing through the fourth air turbine, the pressure is normal pressure.

Compared with the prior art, the present invention has the following beneficial effects:

(1) The system of the present invention couples thermal power equipment and air energy storage equipment, especially extracts a part of the boiler steam in the steam-water system to be used in the air turbine power generation unit of the air energy storage system, and utilizes the characteristics of higher steam temperature. , to improve the temperature and other parameters of the compressed air, thereby improving the power generation capacity of the air turbine and the comprehensive utilization rate of energy of the air energy storage system;

(2) The pressure of the extraction steam at all levels of the steam-water system of the thermal power plant of the present invention has a good match with the pressure of the corresponding compressed air during heat exchange, which helps to balance the pressure on both sides of the heat exchanger and reduces the pressure difference between the inside and outside of the heat exchange tube. and design wall thickness, thereby reducing the amount of heat exchanger material and processing difficulty;

(3) The steam side of the steam-air heat exchanger of the present invention is phase change heat, the heat exchange coefficient is high, the heat exchange area can be reduced, the volume and weight of the heat exchanger can be reduced, and the equipment cost can be reduced.

Description of drawings

1 is a schematic structural diagram of an air energy storage power generation system coupled to thermal power provided by Embodiment 1 of the present invention;

Among them, 1- boiler, 2- high pressure heater, 21- first high pressure heater, 22- second high pressure heater, 23- third high pressure heater, 3- deaerator, 4- steam-air heat exchanger , 41-first steam-air heat exchanger, 42-second steam-air heat exchanger, 43-third steam-air heat exchanger, 44-fourth steam-air heat exchanger, 5-air turbine , 51 - the first air turbine, 52 - the second air turbine, 53 - the third air turbine, 54 - the fourth air turbine.

Detailed ways

In order to better illustrate the present invention and facilitate understanding of the technical solutions of the present invention, the present invention is further described in detail below. However, the following embodiments are only simple examples of the present invention, and do not represent or limit the protection scope of the present invention, and the protection scope of the present invention is subject to the claims.

The specific embodiment of the present invention provides an air energy storage power generation system and method coupled with thermal power. The power generation system includes thermal power equipment and air energy storage power generation equipment. The thermal power equipment includes a boiler 1, a high-voltage heater 2 and a deoxidizer. 3, the air energy storage power generation equipment includes a steam-air heat exchanger 4 and an air turbine 5;

The outlet steam of the boiler 1 is separated from each branch steam pipeline and is connected with the heat source inlet of the high pressure heater 2 and the deaerator 3, and the liquid phase outlet of the deaerator 3 is connected with the cold source inlet of the high pressure heater 2, The cold source outlet of the high-pressure heater 2 is connected to the water inlet of the boiler 1;

The steam-air heat exchanger 4 and the air turbine 5 are both provided with four stages, the steam-air heat exchanger 4 and the air turbine 5 are alternately arranged in series, and the steam side of the steam-air heat exchanger 4 The inlet is connected to the branch pipeline of the steam of the boiler 1, and the air side inlet of the steam-air heat exchanger 4 is the compressed air generated by the air energy storage process.

The following are typical but non-limiting examples of the present invention:

Example 1:

This embodiment provides an air energy storage power generation system coupled with thermal power. The schematic structural diagram of the power generation system is shown in FIG. 1 , including thermal power equipment and air energy storage power generation equipment. The thermal power equipment includes a boiler 1 and a high-voltage heater. 2 and a deaerator 3, the air energy storage power generation equipment includes a steam-air heat exchanger 4 and an air turbine 5;

The outlet steam of the boiler 1 is separated from each branch steam pipeline and is connected with the heat source inlet of the high pressure heater 2 and the deaerator 3, and the liquid phase outlet of the deaerator 3 is connected with the cold source inlet of the high pressure heater 2, The cold source outlet of the high-pressure heater 2 is connected to the water inlet of the boiler 1;

The steam-air heat exchanger 4 and the air turbine 5 are both provided with four stages, the steam-air heat exchanger 4 and the air turbine 5 are alternately arranged in series, and the steam side of the steam-air heat exchanger 4 The inlet is connected to the branch pipeline of the steam of the boiler 1, and the air side inlet of the steam-air heat exchanger 4 is the compressed air generated by the air energy storage process.

The high-pressure heater 2 includes three stages, which are a first high-pressure heater 21, a second high-pressure heater 22 and a third high-pressure heater 23 connected in series in sequence. The liquid phase outlet of the deaerator 3 is connected to the third high-pressure heater. The cooling source inlet of the heater 23 is connected, and the cooling source outlet of the first high-pressure heater 21 is connected with the water inlet of the boiler 1 .

The steam pipes connected to the high-pressure heaters 2 at all levels are arranged in parallel, and all lead out from the outlet steam pipes of the boiler 1;

The steam-air heat exchanger 4 and the air turbine 5 are both provided with four stages, and the steam-air heat exchanger 4 sequentially includes a first steam-air heat exchanger 41 and a second steam-air heat exchanger 42 , the third steam-air heat exchanger 43 and the fourth steam-air heat exchanger 44, the air turbine 5 includes a first air turbine 51, a second air turbine 52, a third air turbine 53 and Fourth air turbine 54 .

The air-side inlet of the first steam-air heat exchanger 41 is connected to compressed air, the air-side outlet of the first steam-air heat exchanger 41 is connected to the inlet of the first air turbine 51, and the first The outlet of the air turbine 51 is connected to the air side inlet of the second steam-air heat exchanger 42, and then the air turbine 5 and the steam-air heat exchanger 4 are alternately connected, and the outlet of the fourth air turbine 54 is connected to the atmosphere .

The steam side inlet of each stage of the steam-air heat exchanger 4 is connected to a branch pipeline of the steam of the boiler 1, and the branch pipelines are arranged in parallel.

The branch pipe of the first steam-air heat exchanger 41 is led out by the steam pipe connected to the first high pressure heater 21 , and the branch pipe of the second steam-air heat exchanger 42 is connected by the second high pressure heater 22 The branch pipe of the third steam-air heat exchanger 43 is drawn out from the steam pipe connected to the third high-pressure heater 23, and the branch pipe of the fourth steam-air heat exchanger 44 is removed from the steam pipe The steam pipeline connected to the oxygenator 3 is led out.

The heat source outlet of the steam-air heat exchanger 4 is connected with the drain pipe of the corresponding high pressure heater 2 , and finally connected to the deaerator 3 .

Example 2:

This embodiment provides an air energy storage power generation system coupled with thermal power. The power generation system includes thermal power equipment and air energy storage power generation equipment. The thermal power equipment includes a boiler 1 , a high-pressure heater 2 and a deaerator 3 . The air energy storage power generation equipment includes a steam-air heat exchanger 4 and an air turbine 5;

The outlet steam of the boiler 1 is separated from each branch steam pipeline and is connected with the heat source inlet of the high pressure heater 2 and the deaerator 3, and the liquid phase outlet of the deaerator 3 is connected with the cold source inlet of the high pressure heater 2, The cold source outlet of the high-pressure heater 2 is connected to the water inlet of the boiler 1;

The steam-air heat exchanger 4 and the air turbine 5 are both provided with three stages, the steam-air heat exchanger 4 and the air turbine 5 are alternately arranged in series, and the steam side of the steam-air heat exchanger 4 The inlet is connected to the branch pipeline of the steam of the boiler 1, and the air side inlet of the steam-air heat exchanger 4 is the compressed air generated by the air energy storage process.

The high-pressure heater 2 includes two stages, namely a first high-pressure heater 21 and a second high-pressure heater 22 connected in series in sequence, the liquid phase outlet of the deaerator 3 and the cold source inlet of the second high-pressure heater 22 connected, the cold source outlet of the first high pressure heater 21 is connected to the water inlet of the boiler 1 .

The steam pipes connected to the high-pressure heaters 2 at all levels are arranged in parallel, and all lead out from the outlet steam pipes of the boiler 1;

The steam-air heat exchanger 4 and the air turbine 5 are both provided with three stages, and the steam-air heat exchanger 4 sequentially includes a first steam-air heat exchanger 41 and a second steam-air heat exchanger 42 and the third steam-air heat exchanger 43 , the air turbine 5 includes a first air turbine 51 , a second air turbine 52 and a third air turbine 53 in sequence.

The air-side inlet of the first steam-air heat exchanger 41 is connected to compressed air, the air-side outlet of the first steam-air heat exchanger 41 is connected to the inlet of the first air turbine 51, and the first The outlet of the air turbine 51 is connected to the air side inlet of the second steam-air heat exchanger 42, and then the air turbine 5 and the steam-air heat exchanger 4 are alternately connected, and the outlet to the third air turbine 53 is connected to the atmosphere .

The steam side inlet of each stage of the steam-air heat exchanger 4 is connected to a branch pipeline of the steam of the boiler 1, and the branch pipelines are arranged in parallel.

The branch pipe of the first steam-air heat exchanger 41 is led out by the steam pipe connected to the first high pressure heater 21 , and the branch pipe of the second steam-air heat exchanger 42 is connected by the second high pressure heater 22 The branch pipe of the third steam-air heat exchanger 43 is led out from the steam pipe connected to the deaerator 3 .

The heat source outlet of the steam-air heat exchanger 4 is connected with the drain pipe of the corresponding high pressure heater 2 , and finally connected to the deaerator 3 .

Example 3:

The present embodiment provides an air energy storage power generation method coupled with thermal power. The method is performed using the system in Embodiment 1, and includes the following steps:

After coupling the air energy storage power generation equipment and the thermal power equipment, the steam of the boiler 1 is used as the heat source of the compressed air. The outlet steam of the boiler 1 passes through the cylinder and the pipeline, and the steam pressure gradually decreases, and different steam pipes are drawn from different positions of the cylinder. The corresponding steam pressures are different, and serve as heat sources for different high-pressure heaters 2 and steam-air heat exchangers 4; the steam pressure in the steam pipeline connected to the first steam-air heat exchanger 41 is 6.38 MPa, so The steam pressure in the steam pipeline connected to the second steam-air heat exchanger 42 is 3.79MPa, the steam pressure in the steam pipeline connected to the third steam-air heat exchanger 43 is 1.75MPa, and the fourth steam - The steam pressure in the steam pipeline connected to the air heat exchanger 44 is 0.89MPa;

The initial pressure of the compressed air is 12MPa, and the temperature is 30°C. The compressed air heated by the steam-air heat exchanger 4 enters the air turbine 5 to generate electricity, and then the steam heating and the air turbine 5 generate electricity alternately. After the air passes through the first steam-air heat exchanger 41, the temperature is 280°C, and after passing through the first air turbine 51, the temperature is 100°C and the pressure is 3.3MPa, and the compressed air passes through the second steam-air heat exchanger. After 42, the temperature is 240°C, and after passing through the second air turbine 52, the temperature is 80°C, and the pressure is 0.9MPa. After the three air turbines 53, the temperature is 65°C and the pressure is 0.26MPa, the temperature of the compressed air after passing through the fourth steam-air heat exchanger 44 is 180°C, and after passing through the fourth air turbine 54, the temperature is 55°C ℃, the pressure is normal pressure, and it is discharged after passing through the fourth air turbine 54.

Example 4:

The present embodiment provides an air energy storage power generation method coupled with thermal power. The method is performed using the system in Embodiment 1, and includes the following steps:

After coupling the air energy storage power generation equipment and the thermal power equipment, the steam of the boiler 1 is used as the heat source of the compressed air. The outlet steam of the boiler 1 passes through the cylinder and the pipeline, and the steam pressure gradually decreases, and different steam pipes are drawn from different positions of the cylinder. The corresponding steam pressures are different and serve as heat sources for different high-pressure heaters 2 and steam-air heat exchangers 4; the steam pressure in the steam pipeline connected to the first steam-air heat exchanger 41 is 3.19 MPa, so The steam pressure in the steam pipeline connected to the second steam-air heat exchanger 42 is 1.89MPa, the steam pressure in the steam pipeline connected to the third steam-air heat exchanger 43 is 0.88MPa, and the fourth steam pressure is 0.88MPa. - The steam pressure in the steam pipeline connected to the air heat exchanger 44 is 0.45MPa;

The initial pressure of the compressed air is 6MPa, and the temperature is 90°C. The compressed air heated by the steam-air heat exchanger 4 enters the air turbine 5 to generate electricity, and then the steam heating and the air turbine 5 generate electricity alternately. After the air passes through the first steam-air heat exchanger 41, the temperature is 220°C, and after passing through the first air turbine 51, the temperature is 90°C and the pressure is 1.65MPa, and the compressed air passes through the second steam-air heat exchanger. After 42, the temperature is 210°C, and after passing through the second air turbine 52, the temperature is 80°C, and the pressure is 0.45MPa. After the three air turbines 53, the temperature is 75°C and the pressure is 0.13MPa, the temperature of the compressed air after passing through the fourth steam-air heat exchanger 44 is 140°C, and after passing through the fourth air turbine 54, the temperature is 70°C ℃, the pressure is normal pressure, and it is discharged after passing through the fourth air turbine 54.

Example 5:

The present embodiment provides an air energy storage power generation method coupled with thermal power. The method is performed using the system in Embodiment 1, and includes the following steps:

After coupling the air energy storage power generation equipment and the thermal power equipment, the steam of the boiler 1 is used as the heat source of the compressed air. The outlet steam of the boiler 1 passes through the cylinder and the pipeline, and the steam pressure gradually decreases, and different steam pipes are drawn from different positions of the cylinder. The corresponding steam pressures are different, and serve as heat sources for different high-pressure heaters 2 and steam-air heat exchangers 4; the steam pressure in the steam pipeline connected to the first steam-air heat exchanger 41 is 4.78 MPa, so The steam pressure in the steam pipeline connected to the second steam-air heat exchanger 42 is 2.84MPa, the steam pressure in the steam pipeline connected to the third steam-air heat exchanger 43 is 1.32MPa, and the fourth steam pressure is 1.32MPa. - The steam pressure in the steam pipeline connected to the air heat exchanger 44 is 0.675MPa;

The initial pressure of the compressed air is 9MPa, and the temperature is 60°C. The compressed air heated by the steam-air heat exchanger 4 enters the air turbine 5 to generate electricity, and then the steam heating and the air turbine 5 generate electricity alternately. After the air passes through the first steam-air heat exchanger 41, the temperature is 250°C, and after passing through the first air turbine 51, the temperature is 95°C and the pressure is 2.47MPa, and the compressed air passes through the second steam-air heat exchanger. After 42, the temperature is 220°C, and after passing through the second air turbine 52, the temperature is 75°C and the pressure is 0.675MPa, the temperature of the compressed air after passing through the third steam-air heat exchanger 43 is 190°C, After the three air turbines 53, the temperature is 70°C and the pressure is 0.195MPa, the temperature of the compressed air after passing through the fourth steam-air heat exchanger 44 is 160°C, and after passing through the fourth air turbine 54, the temperature is 60°C ℃, the pressure is normal pressure, and it is discharged after passing through the fourth air turbine 54.

Example 6:

The present embodiment provides an air energy storage power generation method coupled with thermal power. The method is carried out by using the system in Embodiment 2, and includes the following steps:

After coupling the air energy storage power generation equipment and the thermal power equipment, the steam of the boiler 1 is used as the heat source of the compressed air. The outlet steam of the boiler 1 passes through the cylinder and the pipeline, and the steam pressure gradually decreases, and different steam pipes are drawn from different positions of the cylinder. The corresponding steam pressures are different, and serve as heat sources for different high-pressure heaters 2 and steam-air heat exchangers 4; the steam pressure in the steam pipeline connected to the first steam-air heat exchanger 41 is 6.38 MPa, so The steam pressure in the steam pipeline connected by the second steam-air heat exchanger 42 is 3.79MPa, and the steam pressure in the steam pipeline connected by the third steam-air heat exchanger 43 is 1.75MPa;

The initial pressure of the compressed air is 6.4MPa, and the temperature is 30°C. The compressed air heated by the steam-air heat exchanger 4 enters the air turbine 5 to generate electricity, and then the steam heating and the air turbine 5 generate electricity alternately. After the compressed air passes through the first steam-air heat exchanger 41, the temperature is 280°C, and after passing through the first air turbine 51, the temperature is 50°C and the pressure is 1.8MPa, and the compressed air passes through the second steam-air heat exchange. The temperature after the heat exchanger 42 is 240°C, and after passing through the second air turbine 52, the temperature is 32°C and the pressure is 0.5MPa, the temperature of the compressed air after passing through the third steam-air heat exchanger 43 is 210°C, After the third air turbine 53 , the temperature is 18° C. and the pressure is normal pressure, and it is discharged after passing through the third air turbine 53 .

Comparative Example 1:

This comparative example provides an air energy storage power generation system and method coupled with thermal power. The structure of the power generation system refers to the system in Embodiment 1. The difference is that the heat source inlet of the heat exchanger is not connected to the steam branch of the boiler 1. It is connected to the pipeline, but is connected to the flue gas pipeline of the thermal power plant.

The method refers to the method in Example 3, except that the heat source inlet of the heat exchanger is passed into the thermal power plant flue gas, and the flue gas is used for compressed air heating.

In this comparative example, since the heating of the compressed air takes the flue gas of the thermal power plant as the heat source, the temperature that can be reached before entering the air turbine is relatively low, and the power generation capacity of the air turbine is reduced, which is about 25% lower than that in Example 1; The pressure of the air is basically normal pressure, the pressure difference with the compressed air is large, the average pressure difference on both sides of the heat exchange tube is more than 2 times that in Example 1, the wall thickness of the required heat exchange tube increases, resulting in increased equipment costs .

Combining the above embodiments and comparative examples, it can be seen that the system of the present invention couples thermal power equipment and air energy storage equipment, especially extracts a part of the boiler steam in the steam-water system for the air turbine power generation unit of the air energy storage system , using the characteristics of high steam temperature to improve the temperature of compressed air and other parameters, thereby improving the power generation capacity of the air turbine and the comprehensive utilization rate of energy of the air energy storage system; The pressure matching during air heat exchange is good, which helps to balance the pressure on both sides of the heat exchanger, reduces the pressure difference between the inside and outside of the heat exchange tube and the designed wall thickness, thereby reducing the amount of heat exchanger materials and the difficulty of processing; the steam -The steam side of the air heat exchanger is phase-change heat, and the heat transfer coefficient is high, which can reduce the heat exchange area, reduce the volume and weight of the heat exchanger, and reduce the equipment cost.

The applicant declares that the present invention illustrates the detailed system and method of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned detailed system and method, that is, it does not mean that the present invention must rely on the above-mentioned detailed system and method to be implemented. Those skilled in the art should understand that any improvement to the present invention, the equivalent replacement of the system of the present invention, the addition of auxiliary equipment, the selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims (10)

1. The air energy storage power generation system coupled with thermal power is characterized by comprising thermal power equipment and air energy storage power generation equipment, wherein the thermal power equipment comprises a boiler, a high-pressure heater and a deaerator, and the air energy storage power generation equipment comprises a steam-air heat exchanger and an air turbine;

each branch of steam pipeline of the outlet steam of the boiler is connected with the high-pressure heater and a heat source inlet of a deaerator, a liquid phase outlet of the deaerator is connected with a cold source inlet of the high-pressure heater, and a cold source outlet of the high-pressure heater is connected with a water inlet of the boiler;

the steam-air heat exchanger and the air turbine are at least provided with two stages, the steam-air heat exchanger and the air turbine are alternately connected in series, a steam side inlet of the steam-air heat exchanger is connected with a branch pipeline of boiler steam, and an air side inlet of the steam-air heat exchanger is compressed air generated in an air energy storage process.

2. An air energy storage power generation system according to claim 1, wherein said high pressure heater comprises at least two stages, preferably three stages;

preferably, the high pressure heater includes first high pressure heater, second high pressure heater and the third high pressure heater of establishing ties in proper order, the liquid phase export of oxygen-eliminating device links to each other with the cold source entry of third high pressure heater, the cold source export of first high pressure heater links to each other with the water inlet of boiler.

3. The air energy storage power generation system according to claim 1 or 2, wherein the steam pipelines connected with the high-pressure heaters of each stage are arranged in parallel and are led out from the outlet steam pipeline of the boiler;

preferably, the heat source outlet of each stage of high-pressure heater is connected with the water inlet of the deaerator through a drain pipe.

4. The air energy storage and power generation system according to any one of claims 1-3, wherein the steam-air heat exchanger and the air turbine are provided with four stages, the steam-air heat exchanger comprises a first steam-air heat exchanger, a second steam-air heat exchanger, a third steam-air heat exchanger and a fourth steam-air heat exchanger in sequence, and the air turbine comprises a first air turbine, a second air turbine, a third air turbine and a fourth air turbine in sequence;

preferably, the air-side inlet of the first steam-air heat exchanger is connected to compressed air, the air-side outlet of the first steam-air heat exchanger is connected to the inlet of the first air turbine, the outlet of the first air turbine is connected to the air-side inlet of the second steam-air heat exchanger, the air turbine and the steam-air heat exchanger are alternately connected, and the outlet of the fourth air turbine is connected to the atmosphere.

5. An air energy storage and power generation system according to any one of claims 1-4, wherein the steam side inlet of each stage of steam-air heat exchanger is connected with a branch pipeline of boiler steam, and the branch pipelines are arranged in parallel;

preferably, the branch pipe of the first steam-air heat exchanger is led out by a steam pipeline connected with the first high-pressure heater, the branch pipe of the second steam-air heat exchanger is led out by a steam pipeline connected with the second high-pressure heater, the branch pipe of the third steam-air heat exchanger is led out by a steam pipeline connected with the third high-pressure heater, and the branch pipe of the fourth steam-air heat exchanger is led out by a steam pipeline connected with the deaerator;

preferably, the heat source outlet of the steam-air heat exchanger is connected with a corresponding drain pipe of the high-pressure heater and finally connected to the deaerator.

6. A method of generating electricity from stored energy in air using the system of any one of claims 1 to 5, the method comprising the steps of:

after the air energy storage power generation equipment is coupled with thermal power equipment, boiler steam is used as a heat source of compressed air, the heated compressed air enters an air turbine to generate power, and then steam heating and air turbine power generation are alternately carried out until the heated compressed air passes through a last stage of air turbine and is discharged.

7. The method according to claim 6, characterized in that outlet steam of a boiler in the thermal power plant passes through a cylinder and a pipeline, and the steam pressure is gradually reduced;

preferably, different steam pipelines are led out from different positions of the cylinder, and corresponding steam pressures are different to be used as heat sources of different high-pressure heaters and steam-air heat exchangers.

8. The method according to claim 6 or 7, wherein the steam pressure in a steam pipeline connected with the first steam-air heat exchanger is 3.19-6.38 MPa;

preferably, the steam pressure in a steam pipeline connected with the second steam-air heat exchanger is 1.89-3.79 MPa;

preferably, the steam pressure in a steam pipeline connected with the third steam-air heat exchanger is 0.88-1.75 MPa;

preferably, the steam pressure in a steam pipeline connected with the fourth steam-air heat exchanger is 0.45-0.89 MPa.

9. The method according to any one of claims 6 to 8, wherein the compressed air has an initial pressure of 6 to 12MPa and a temperature of 10 to 110 ℃;

preferably, the compressed air is heated by a steam-air heat exchanger, expanded by an air turbine to generate power at a lower temperature and pressure, and then alternately enters the steam-air heat exchanger and the air turbine.

10. The method according to any one of claims 6 to 9, wherein the compressed air has a temperature of 220 to 280 ℃ after passing through the first steam-air heat exchanger and a pressure of 1.65 to 3.3MPa after passing through the first air turbine;

preferably, the temperature of the compressed air after passing through the second steam-air heat exchanger is 200-240 ℃, and the pressure of the compressed air after passing through the second air turbine is 0.45-0.9 MPa;

preferably, the temperature of the compressed air after passing through a third steam-air heat exchanger is 170-210 ℃, and the pressure of the compressed air after passing through a third air turbine is 0.13-0.26 MPa;

preferably, the temperature of the compressed air after passing through the fourth steam-air heat exchanger is 140-180 ℃, and the pressure of the compressed air after passing through the fourth air turbine is normal pressure.

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