RU2643878C1 - Method of operation of the compressed-air power station with an absorption lithium bromide refrigerating system (lbrs) - Google Patents

Abstract

FIELD: power engineering.

SUBSTANCE: invention relates to power engineering. Method of operation of the compressed-air power station (CAPS) with an absorption lithium bromide refrigerating system (LBRS) in the power load decline period, comprises additional cooling the compressed air, pre-cooled in the intercooler in an additional installed compressed air cooler, which is connected to the evaporator of LBRS, in which the generator heating circuit is connected at the inlet and outlet to the circulating water return pipeline, condenser cooling circuit and the absorber cooling circuit are connected at the inlet to the circulating water supply pipeline, and at the outlet – to a cooling tower, additionally cooled, thereby increased air flow is directed to an air accumulator.

EFFECT: invention provides increased amount of air pumped into the air accumulator, which leads to increasing amount of combustion products passing through the flowing part of the gas turbine during the discharge of the CAPS, and thus to increasing in the electric power of the CAPS with LBRS, electrical efficiency and specific energy production per unit of the storage volume.

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Description

The invention is intended to generate electricity when covering a variable load of power consumption based on air energy storage technology and can be used in the power industry.

There are various schemes of air-accumulating gas turbine power plants (VAGTE) that realize the possibility of using the electricity generated at night to cover peak loads. The AHTEG compressor group is driven by an electric motor that consumes cheap electricity. Air pre-cooled by circulating water of the technical water supply system to a temperature higher than the ambient temperature is pumped into the air accumulator, where it is stored in a compressed form. At peak electric load hours, air is taken from the air accumulator, used in the process of fuel combustion, and expanded in a turbine rotating an electric generator.

At the same time, the well-known properties of absorption chillers, which allow transforming thermal energy into cold in the technological cycles of power plants to increase the efficiency of their operation, are not fully used in VAGTE schemes.

There are a number of studies on the use of absorption refrigeration machines in the technological cycles of various types of power plants to increase their efficiency.

A known model of a thermal power plant [Patent for utility model 150039, F01K 13/00 - No. 2014114040/06. Thermal power station / Efimov N.N., Skubienko S.V., Yanchenko I.V.]. In the technological cycle of the thermal power plant, an absorption type heat pump (ABTN) is used, with the evaporation circuit connected to the supply and exhaust pipelines of the cooling water of the steam turbine condenser and with the connection of the last low pressure heater (PND) along the path of the steam of the regeneration system to the ABTN condenser. The method allows to ensure the reliability of power equipment at rated loads and to increase the efficiency of the regenerative cycle of only thermal power plants.

A known model of a thermal power plant [Utility Model Patent No. 119393, F01K 17/06, F25B 27/02. Thermal power station with an absorption lithium bromide refrigeration machine / Dogadin DL, Krykin IN, Latypov GG] A thermal power station contains an absorption lithium bromide refrigeration machine to increase thermal energy utilization of TPPs. The lithium-bromide absorption chiller is connected to a closed coolant circuit with additional heating of the coolant by thermal energy of a pair of elements of the technological circuit of a thermal power station and with an open cooler loop connected to a cooling medium source, characterized in that the lithium bromide-chiller is connected to a closed loop refrigerant associated with the consumer of the cold, a closed coolant circuit is integrated through the heat exchanger into the main condensate atnuyu line combined cycle gas turbine for a gas preheater condensate recovery boiler before the deaerator tank and comprises a damper fluid. This invention is applicable to improve the efficiency and reliability of power equipment only thermal power plants.

A known model of a thermal power plant [Utility Model Patent No. 119394, F01K 17/06, F25B 27/02. Thermal power station with absorption lithium bromide refrigeration machine / Latypov GG, Krykin IN, Dogadin DL]. A thermal power station with an absorption lithium bromide chiller contains an absorption lithium bromide chiller connected to a coolant circuit with additional heating of the coolant with steam and an open cooler circuit connected to a circulation circuit of a technical water supply system of a thermal power station, characterized in that the absorption bromide lithium chiller is made with a closed coolant circuit connected to a consumer of cold, circuit t A heat carrier is included in the technological scheme of a thermal power station and connected to steam pipelines. The technical result is to increase the efficiency of the TPP by reducing the temperature of the cooling water in the technological scheme of TPP. This invention is applicable to improve the efficiency and reliability of power equipment only thermal power plants.

A known model of a thermal power plant [Utility Model Patent No. 127818, F01K 17/00. Thermal power station with an absorption lithium bromide refrigeration machine operating in the heat pump mode / Dogadin DL]. A thermal power plant containing an absorption lithium bromide refrigeration machine connected to a coolant circuit, a coolant circuit connected to internal and external cold consumers, characterized in that the lithium bromide absorption refrigeration machine is made with a coolant circuit combined with a water preparation circuit for the system heat supply for TPP consumers and TPP own needs. The technical result is to ensure a stable year-round operation of cooling systems of technological equipment of TPPs with minimal heat loss to the environment, which in turn leads to the elimination of technological restrictions on the generation of power and electricity in both winter and summer, improving performance indicators TPP as a whole.

A known model of a thermal power plant [Utility Model Patent No. 81259, F01K 13/00. Thermal power station / Efimov N.N., Lapin I.A., Malyshev P.A., Popov R.V., Radaev P.N., Cherny A.V., Lemeshev A.A., Karataev G.B. ., Skubienko S.V., Oshchepkov A.S.]. The thermal power plant consists of a steam turbine, a condenser with a package of pipes built in it, a condensate pump, a system of low and high pressure heaters, a deaerator, a feed pump, a boiler, a heat pump consisting of a heat exchanger-evaporator, heat exchanger-condenser, compressor and inductor, moreover, the heat exchanger-evaporator of the heat pump is connected to the tube bundle or to the entire package of pipes of the condenser of the steam turbine. The cost-effectiveness of a thermal power plant when installing a heat pump is increased by maintaining lower condensation temperatures of the steam in the condenser and increasing the temperature of the heat transfer to the consumer, compared with steam turbines with an integrated heating tube bundle, however, this invention is applicable only to thermal power plants.

A known method of operation of an air-accumulating gas turbine installation [Patent for the invention No. 2529615, IPC F01K 25/06. The method of energy storage / Stolyarevsky A.Ya.]. The method allows, by utilizing the thermal energy of the combustion products in the steam generator and using compressed air stored in the storage due to the failed electricity, to obtain a hydrogen-containing gas mixture with a high hydrogen content, the combustion of which increases the power of the gas turbine in peak mode and reduces emissions of harmful substances. During periods of failure of the electrical load schedule, the air taken from the environment is compressed in the compressor, it is supplied to the storage, pre-cooled in a heating heat exchanger, in which the heat carrier, heating water supplied to the heating and hot water supply network, is heated. However, the use of district heating water does not allow sufficiently deep cooling of compressed air in front of the air reservoir.

A known method of operation of an air-accumulating gas turbine power plant (VAGTE) [Olkhovsky G.G. etc. Air-accumulating gas turbine power plants (VAGTE). M., Russian State University of Oil and Gas named after I.M. Gubkina, 2011, p. 131, Fig. 3.9], containing an underground battery of constant pressure, which is supported by a column of liquid connecting the underground tank with a reservoir located on the surface. When air is consumed, water fills the battery; when charging, it is forced into the pond. In the period of a decrease in the electrical load in compressors of low, medium and high pressure, the air taken from the environment is compressed, it is cooled in the intermediate air coolers by circulating water from the cooling tower. After the high-pressure compressor, the compressed air is also cooled in the end cooler by circulating water from the tower to 60 ° C and sent to the air accumulator. During the rise of the electrical load, the compressed air is directed to a gas turbine regenerator. Heated compressed air in the regenerator is sent to a high-pressure combustion chamber, mixed with fuel and an increased volume of combustion products is fed into the flow part of a high-pressure gas turbine (HPT). From the high pressure fuel, the combustion products are sent to the low-pressure combustion chamber, mixed again with the fuel and fed to the flow part of the low-pressure gas turbine (LPT). The disadvantage of this method is not sufficiently deep lowering the temperature of the compressed air in front of the air accumulator in order to increase the volume of injected air.

A known method of operation of a fuel-free VAGTE [Olkhovsky G.G. etc. Air-accumulating gas turbine power plants (VAGTE). M., Russian State University of Oil and Gas named after I.M. Gubkina, 2011, Fig. 6.3], containing an underground air accumulator, containers for cold coolant, air coolers, a compressor group, a source of cooling water, air heaters, a turbine group, hot heat accumulators. Before air is pumped into the underground battery, its temperature decreases from 187 to 64.5 ° C with circulating water. The disadvantage of this method is not sufficiently deep lowering the temperature of the compressed air in front of the air reservoir in order to increase the volume of injected air.

The closest technical solution (analog) is the method of operation of a fuel-free air-accumulating gas turbine power plant [Patent for invention No. 2574105, IPC F01K 3/00. Method and system for capturing thermal energy in a power generation system (options) / Anihindi Sanjay, Kosaman Bhaskara]. A system for collecting thermal energy in a power generation system comprises a first compressor configured to discharge a first compressed heated air stream, a heat exchanger connected to a first compressor and configured to receive a first compressed heated air stream and capable of transferring thermal energy from a first compressed heated stream air to oil, at least one pump connected to a heat exchanger and configured to pump heated oil in a closed system Birmingham from the heat exchanger in an insulated tank, the second compressor coupled to the heat exchanger and configured to release second compressed heated air stream, and power storage device coupled to the second compressor and adapted to accumulate heat energy from the second compressed heated air stream. The system comprises an absorption cooler used in the initial stages of electric power production to cool the air discharged from the axial compressor before being fed to the first centrifugal compressor. The system also contains a spare cooler, where the compressed air after the heat accumulator is cooled to 50 ° C before going to the storage cavity of compressed air. As a rule, the cooling of compressed air after a heat accumulator is carried out by circulating water of a technical water supply system.

The disadvantage of the analogue is that the absorption chiller is used only for cooling the air in the compressor group: before being fed to the axial compressor and between the axial and first centrifugal compressors, while the air is cooled before being fed into the air storage in the traditional way - by circulating water to a temperature exceeding the temperature the environment.

The technical problem is the insufficient cooling of the compressed air supplied to the storage, which leads to a decrease in the amount of injected air and, accordingly, the generation of peak electricity by an air-accumulating gas turbine power plant.

The technical problem is solved by the method of operation of an air-accumulating gas-turbine power plant with an absorption lithium bromide chiller (ABHM), which consists in the fact that during the period of a decrease in electric load, compressed air pre-cooled in an intercooler is additionally cooled in an additionally installed compressed air cooler, which is connected to the evaporator of an absorption refrigeration lithium bromide machine, in which the generator heating circuit is connected at the inlet and outlet to the return the circulation water supply, the condenser cooling circuit and the absorber cooling circuit are connected at the inlet to the circulation water supply pipe, and at the outlet to the cooling tower, additionally cooled, thereby increasing the air flow rate, is sent to the air accumulator.

The essence of the claimed invention lies in the fact that in the method of operation of an air-accumulating gas-turbine power plant with ABHM during the night period of decline in electric load, the air is additionally cooled to increase its amount pumped into the storage, in an additional cooler connected to the ABHM evaporator, which uses heat which is compressed in air compressor, during the period of a daily rise in electrical load, the increased consumption of compressed air is used to burn fuel in the combustion chamber and is directed To expand and do work in the gas turbine.

The technical result consists in increasing the amount of air pumped into the air accumulator, which leads to an increase in the volume of combustion products passing through the flow part of the gas turbine during the discharge mode of the AHTFE, and thereby to an increase in the electric power of an air-accumulating gas-turbine power plant with ABHM, electric efficiency and specific energy production per unit volume of storage.

The technical result of the claimed invention is achieved due to the method of operation of an air-accumulating gas turbine power plant with an absorption lithium bromide refrigeration machine (ABHM), which consists in additional cooling of air pre-compressed by a low-pressure compressor and cooled in an intercooler by circulating water cooling tower, then compressed by a high-pressure compressor and a cooling tower cooled in a second intermediate cooler with circulating water, in an additional compressed cooler air connected to the evaporator ABHM. In this case, the heating circuit of the ABHM generator (coolant circuit) is connected to the return circulation water pipe, the cooling circuit of the absorber absorber ABHM and the cooling circuit of the condenser ABHM at the inlet are connected to the supply pipe of the circulation water, and at the outlet, to the cooling tower. The additional cooling of compressed air in an additional cooler of compressed air leads to an increase in its amount of supply to the air accumulator. During the period of a daily rise in electrical load, the increased flow rate of compressed air is mixed with the fuel in the combustion chamber and directed to expand and perform work in a gas turbine.

As a result of the proposed method increases the electrical power of the AHTFE, the efficiency of the production of peak energy, the specific supply of energy per unit flow rate of accumulated air. It should be noted that in the composition of VAGTE it is possible to use a different number of compressors and gas turbines, different from the amount presented in the claimed method, which will not affect the essence of the invention and the achieved technical result.

The invention is illustrated using the figure, which shows a diagram of an air-accumulating gas turbine power plant with ABHM, which implements the inventive method. The positions in the drawing indicate:

1 - low pressure compressor;

2, 4 - intermediate air coolers;

3 - high pressure compressor;

5 - cooling tower;

6 - feed pipe for circulating water;

7 - return pipe of circulating water;

8, 23 - pipelines of compressed air;

9 - additional cooler of compressed air;

10 - air battery;

11 - absorption lithium bromide refrigeration machine (ABHM);

12 - evaporator ABHM;

13 - chilled water pump;

14 - absorber ABHM;

15 - cooling circuit of the absorber ABHM;

16 - generator ABHM;

17 - capacitor ABHM;

18 - cooling circuit of the condenser ABHM;

19 - heating circuit of the generator ABHM;

20 - pipeline hot weak solution;

21 - heat exchanger;

22 - pipeline cold cold mortar;

24 - combustion chamber;

25 - gas turbine;

26 - an electric generator;

27 - an electric motor;

28 - condensate pipeline;

29 - chilled water pipeline;

30 - absorbent pump;

31 - flue gas duct of a gas turbine;

32 - regenerator.

Installation for implementing the proposed method includes: a low pressure compressor 1 and a high pressure compressor 2, driven by an electric motor 27; intermediate air coolers 2 and 4, connected with the cooling tower 5 by means of a supply pipe of circulating water 6 and a return pipe of circulating water 7; an additional compressed air cooler 9 connected by a compressed air pipe 8 with an intermediate air cooler 4 and an air accumulator 10; lithium bromide absorption refrigeration machine (ABHM) 11 connected by a chilled water pipe 29 with an additional compressed air cooler 9; ABXM evaporator 12 connected by a chilled water pipe 29 with an additional compressed air cooler 9 and a condensate pipe 28 with a condenser ABXM 17; a chilled water pump 13 connected by a chilled water pipe 29 with an additional compressed air cooler 9 and an ABHM 12 evaporator; absorber ABHM 14, connected by a pipeline of hot weak solution 20 and a pipeline of a cold strong solution 22 with a generator ABHM 16; the cooling circuit of the absorber ABXM 15 associated with the supply pipe of the circulation water 6 and cooling tower 5; the condenser cooling circuit ABXM 18 associated with the supply pipe of the circulation water 6 and cooling tower 5; the heating circuit of the generator ABHM 19 associated with the return pipe of the circulation water 7; a heat exchanger 21 connected by a pipeline of a hot weak solution 20 and a pipeline of a cold strong solution 22 with an absorber ABHM 14 and a generator ABHM 16; an electric generator of a gas turbine 26 driven by a gas turbine 25; a regenerator 32, connected through a compressed air pipe 23 to an air accumulator 10, through a combustion chamber 24 and a flue gas duct of a gas turbine 31 to a gas turbine 25.

The proposed method of operation of an air-accumulating gas turbine power plant with an absorption lithium bromide refrigeration machine (ABHM) is as follows.

During the recession of the electrical load, the low-pressure compressor 1 and the high-pressure compressor 3 are driven by an electric motor 27, consuming electricity from the network.

Compressed air by low-pressure compressor 1, pre-cooled in the intermediate air cooler 2, is supplied to the high-pressure compressor 3. To cool this compressed air stream, part of the cooled circulating water from the supply pipe of the circulation water 6 connected to the cooling tower 5 is fed to the intermediate air cooler 2 , cooled by compressed air compressor 1 low pressure 1, the heated circulating water is then sent to the return pipe of the circulating water 7.

Compressed air by a high-pressure compressor 3, pre-cooled in an intermediate air cooler 4 and in an additional compressed air cooler 9, is supplied to the air accumulator 10. To cool this air flow into the intermediate air cooler 4, a part of the cooled circulation water stream from the supply water circulation pipe 6 is supplied, connected to the cooling tower 5, the heated stream of circulating water is then sent to the return pipe of circulating water 7.

Through the pipeline of compressed air 8, compressed air is pumped into the air accumulator 10, additionally cooling in an additional compressed air cooler 9.

To cool the compressed air in the intermediate air coolers 2 and 4, the circulating water cooled in the cooling tower 5 is used, which is fed through the supply pipe of the circulation water 6, the heated circulation water after the intermediate air coolers 2 and 4 is sent to the return pipe of the circulation water 7 and then to the cooling tower 5 .

In the evaporator ABHM 12, which is part of an absorption lithium bromide refrigeration machine (ABHM) 11, water-refrigerant is supplied from the condenser ABHM 17, connected to an additional compressed air cooler 9 with a chilled water pipe 29, through which cooling water is pumped by a chilled water pump 13 for additional cooling of the compressed air before feeding it into the air accumulator 10. Two flows are removed from the ABHM 12 evaporator: water-refrigerant for additional cooling of the compressed air and steam to the ABXM absorber 14.

A weak solution of lithium bromide is fed into the absorber ABHM 14, where water-refrigerant vapors are absorbed. In order to prevent the temperature of lithium bromide from rising and the loss of its absorbing properties, the ABXM 15 absorber cooling circuit is used, the inlet of which is connected to the supply pipe of circulating water 6, and the output to the cooling tower 5.

After absorption, the lithium bromide solution is pumped by the absorbent pump 30 to the ABHM 16 generator. There, under the influence of the heating water of the heating circuit of the ABHM 19 generator, the inlet and outlet of which is connected to the return water circulation pipe 7, a part of the water is evaporated from the solution. Thereby, the initial concentration of lithium bromide in the solution is restored, which is necessary to maintain its absorbent properties.

In the heat exchanger 21, the hot weak solution, which is supplied through the pipeline of the hot weak solution 20, is cooled with a cold strong solution, which is pumped from the absorber ABXM 14 to the generator ABXM 16 using the pump of the absorbent 30 through the pipeline of a cold strong solution 22.

In the condenser ABHM 17 condensate water vapor refrigerant formed during boiling of a solution of lithium bromide in the generator ABHM 16, use for this cooling water in the cooling circuit of the condenser ABHM 18, the input of which is connected to the supply pipe of the circulation water 6, and the output to the cooling tower 5. After this condensed water-refrigerant is fed into the evaporator ABHM 12 and the cycle repeats.

During the rise of the electric load, compressed air from the air accumulator 10 is sent through a compressed air pipe 23 to the regenerator 32 and then to the combustion chamber 24 of the gas turbine 25. In the combustion chamber 24, the compressed air heated in the exhaust gas 32 of the gas turbine 25 is used to burn fuel, the resulting combustion products are fed into a gas turbine 25 for expansion and execution of work. The gas turbine 25 drives an electric generator 26 that generates electricity. The flue gases of the gas turbine 25 along the flue gas duct of the gas turbine 31 are sent to heat the compressed air to the regenerator 32.

As an example, we consider the method of operation of an air-accumulating gas turbine power plant with ABCM for the following conditions. VAGTE includes a constant pressure air accumulator, into which air is supplied with a pressure of 6.6 MPa. The air pressure in front of the combustion chamber is 5.5 MPa; the temperature of the combustion products in front of the gas turbine adopted 1300 ° C. The operation time of the AHTFE in the charging mode is 4 hours / day, in the discharge mode - 6 hours / day.

The table shows the results of the calculation of the VAGTE scheme using an absorption lithium bromide refrigeration machine (ABHM) for cooling compressed air in front of the air battery and the VAGTE scheme without ABHM.

As can be seen, the use in the VAGTE scheme of an absorption lithium bromide chiller (ABHM) for cooling compressed air in front of the air accumulator allows increasing the volume of air pumped into the air accumulator by 5382 m ³ / h (1.2%), which leads to an increase in electric power 2.43 MW (2%); electrical efficiency - by 0.53%; specific energy production per unit flow rate of accumulated air - by 1.7%.

Thus, the proposed technical solution allows you to:

- additional cooling of the air supplied to the storage during the charging mode of the air-accumulating gas-turbine power station with ABHM;

- increase in the amount of air pumped into the air accumulator;

- improving the efficiency of the production of peak electricity with constant operation of the compressor, which supplies compressed air to the air battery;

- increasing the electric power of the air-accumulating gas turbine power plant with ABHM due to the increase in the volume of combustion products passing through the flow part of the gas turbine during the discharge mode of the VAGTE;

- increase in electrical efficiency and specific energy production per unit volume of storage.

Claims (1)

The method of operation of an air-accumulating gas-turbine power plant with an absorption lithium bromide refrigeration machine (ABHM), characterized in that during the period of a decrease in the electric load, the air taken from the environment is compressed in the low-pressure compressor, it is cooled in the intermediate air cooler by circulating water from the cooling tower, and it is guided compressed air flow to the high-pressure compressor, after which the compressed air is also cooled in the intermediate air cooler by circulating water from the cooling tower, in Once the electric load is lifted, compressed air is directed to the gas turbine regenerator, heated in the exhaust gas of the gas turbine, sent to the combustion chamber of the gas turbine, mixed with fuel and an increased volume of combustion products is fed into the flow part of the gas turbine, characterized in that during the decline of the electric turbine compressed air pre-cooled in the intercooler is additionally cooled in an additionally installed compressed air cooler, which is connected to the evaporator absorption lithium bromide refrigeration machine, in which the generator heating circuit is connected at the inlet and outlet to the circulation water return pipe, the condenser cooling circuit and the absorber cooling circuit are connected at the inlet to the circulation water supply pipe, and at the output, connected to the cooling tower, further cooled, the most increased air flow is directed to the air battery.

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