Dry rock heat storage system coupled with coal-fired cogeneration unit
Through the dry rock heat storage system coupled with the coal-fired cogeneration unit, the problems of high costs, high pollution and difficulty in deep peak shaving in existing thermoelectric technologies are solved, and the low-cost, efficient and environmentally friendly heat storage effect is achieved, meeting the heat needs of residents and improving the peak shaving capacity of cogeneration units.
Patent Information
- Application Number
- CN202311215623.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-09-19
- Publication Date
- 2025-03-21
AI Technical Summary
There are prominent contradictions in existing thermoelectric technologies, including high costs, high pollution, and deep peak shaving and ensuring residents' heat.
The dry rock heat storage system coupled with the coal-fired cogeneration unit is adopted. The dual functions of heat storage and energy release are realized through boilers, generators, condensers, low-pressure heater groups, deaerators, high-pressure heater groups, thermal network circulation water pumps, thermal network heaters, boost pumps, electric regulating valves, external coil heat exchangers, built-in electric heaters, adiabatic storage devices and temperature collection devices.
It achieves a low-cost, efficient and environmentally friendly heat storage effect, can meet residents' heat consumption needs under deep peak shaving conditions, reduce pollution emissions, and improve the peak shaving capacity of cogeneration units.
Smart Images
Figure HDA0004458858490000011
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of energy storage in coal-fired power plants, and specifically discloses a dry rock heat storage system coupled with a coal-fired cogeneration unit. Background Art
[0002] The current thermal-electric decoupling technologies mainly include low-pressure cylinder zero output, hot water heat storage and electric boiler heat storage, etc. In view of the high cost, high pollution and prominent contradiction between deep peak regulation and guarantee of heat supply for residents in the current thermal-electric decoupling technologies, we proposed a dry rock heat storage system coupled with a coal-fired cogeneration unit, which can realize low-cost, efficient and environmentally friendly heat storage, and can meet the heat demand of residents on the basis of deep peak regulation. Summary of the invention
[0003] The main technical problem solved by the present invention is to provide a dry rock heat storage system coupled with a coal-fired cogeneration unit, which can solve the problems existing in the existing thermal power technology, such as high cost, high pollution, and prominent contradiction between deep peak regulation and ensuring residents' heating supply.
[0004] In order to solve the above technical problems, a technical solution adopted by the present invention is:
[0005] A dry rock heat storage system coupled with a coal-fired heat and power cogeneration unit, characterized in that it includes a boiler 1, a high-pressure cylinder a2, a medium-pressure cylinder b3, a low-pressure cylinder c4, a generator 5, a condenser 6, a condensate pump a7, a low-pressure heater group 8, a deaerator 9, a feed pump b10, a high-pressure heater group 11, a heat network circulating water pump c12, a heat network heater 13, a booster pump d14, an electric regulating valve a15, an electric regulating valve b16, an electric regulating valve c17, an electric regulating valve d18, an external coil heat exchanger 19, a built-in electric heater 20, an adiabatic storage device 21 and a temperature collection device 22. The main steam-water circulation process is as follows: boiler 1-high-pressure cylinder a2-boiler 1-medium-pressure cylinder b3-low-pressure cylinder c4-condenser 6-condensate pump a7-low-pressure heater group 8-deaerator 9-feed pump b10-high-pressure heater group 11 back to boiler 1.
[0006] The steam-water flow of the heating system is as follows: the steam extracted from the low-pressure cylinder enters the heating network heater 13 through the electric regulating valve a15, heats the circulating water of the heating network and returns to the condenser 6 through the electric regulating valve b16. After the circulating water of the heating network passes through the circulating water pump c12 of the heating network, the internal temperature of the adiabatic storage device 21 is obtained through the temperature acquisition device 22, and the amount of water that can be heated is calculated, so that the calculated amount of water enters the adiabatic storage device 21 through the electric regulating valve c17 and the booster pump d14, is heated by the external coil heat exchanger 19, enters the outlet of the heating network heater 13 through the electric regulating valve d18, and is supplied to users through the heating network pipeline. The water obtained by deducting the amount of water that can be heated from the total water volume enters the heating network heater 13, is heated by the steam extracted from the low-pressure cylinder, enters the outlet of the heating network heater 13, and is supplied to users through the heating network pipeline.
[0007] The heat storage system structure is as follows: an external coil heat exchanger 19 is installed inside the adiabatic storage device 21, and internal electric heaters 20 are evenly arranged at equal intervals inside the external coil heat exchanger 19. The gap between the external coil heat exchanger 19 and the internal electric heater 20 is filled with dry rocks. The internal electric heater 20 can heat the dry rocks inside it, and the external coil heat exchanger 19 can realize heat exchange between the circulating water of the heat network and the dry rocks. The generator 5 supplies power to the internal electric heater 20 through a cable.
[0008] The system includes two stages of heat storage and energy release during operation. When the power output of the coal-fired cogeneration unit is greater than the grid demand, it enters the heat storage stage; when the power output of the coal-fired cogeneration unit is less than the demand, it enters the energy release stage.
[0009] Heat storage stage: The excess electric energy of the generator 5 is output to the built-in electric heater 20, which converts the electric energy into heat energy and stores it in the dry rock. A temperature acquisition device (22) is provided inside the adiabatic storage device 21, and heat storage is automatically stopped when the temperature reaches the upper limit of heat storage 800°C. At this time, the electric regulating valve c17 and the electric regulating valve d18 are closed, and the booster pump d14 is stopped.
[0010] Energy release process: Turn on the booster pump d14, the electric regulating valve c17 and the electric regulating valve d18. Part of the condensate from the outlet of the self-heating network circulating water pump c12 is pressurized by the electric regulating valve b16 and the booster pump d14 and enters the external coil heat exchanger 19. After absorbing heat and rising in temperature, it passes through the electric regulating valve d18 and enters the outlet of the heating network heater 13, and is supplied to users through the heating network pipeline. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Figure 1 It is a schematic diagram of the process flow of the present invention. DETAILED DESCRIPTION
[0012] The following is combined with Figure 1The present invention is further described in detail with specific implementation modes so that the objects, advantages and technical solutions of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.
[0013] A dry rock heat storage system coupled with a coal-fired cogeneration unit is characterized by comprising a boiler 1, a high-pressure cylinder a2, a medium-pressure cylinder b3, a low-pressure cylinder c4, a generator 5, a condenser 6, a condensate pump a7, a low-pressure heater group 8, a deaerator 9, a feed water pump b10, a high-pressure heater group 11, a heat network circulating water pump c12, a heat network heater 13, a booster pump d14, an electric regulating valve a15, an electric regulating valve b16, an electric regulating valve c17, an electric regulating valve d18, an external coil heat exchanger 19, a built-in electric heater 20, an adiabatic storage device 21 and a temperature acquisition device 22.
[0014] The main steam-water circulation process is as follows: boiler 1—high-pressure cylinder a2—boiler 1—medium-pressure cylinder b3—low-pressure cylinder c4—condenser 6—condensate pump a7—low-pressure heater group 8—deaerator 9—feedwater pump b10—high-pressure heater group 11 back to boiler 1.
[0015] The steam-water flow of the heating system is as follows: the steam extracted from the low-pressure cylinder enters the heating network heater 13 through the electric regulating valve a15, heats the circulating water of the heating network and returns to the condenser 6 through the electric regulating valve b16. After the circulating water of the heating network passes through the circulating water pump c12 of the heating network, the internal temperature of the adiabatic storage device 21 obtained by the temperature acquisition device is used to calculate the amount of water that can be heated, so that the calculated amount of water enters the adiabatic storage device 21 through the electric regulating valve c17 and the booster pump d14, is heated by the external coil heat exchanger 19, enters the outlet of the heating network heater 13 through the electric regulating valve d18, and is supplied to users through the heating network pipeline. The water obtained by deducting the above-calculated amount of water that can be heated from the total water volume enters the heating network heater 13, is heated by the steam extracted from the low-pressure cylinder, enters the outlet of the heating network heater 13, and is supplied to users through the heating network pipeline.
[0016] The heat storage system structure is as follows: an external coil heat exchanger 19 is installed inside the adiabatic storage device 21, and internal electric heaters 20 are evenly arranged at equal intervals inside the external coil heat exchanger 19. The gap between the external coil heat exchanger 19 and the internal electric heater 20 is filled with dry rocks. The internal electric heater 20 can heat the dry rocks inside it, and the external coil heat exchanger 19 can realize heat exchange between the circulating water of the heat network and the dry rocks. The generator 5 supplies power to the internal electric heater 20 through a cable.
[0017] The system includes two stages of heat storage and energy release during operation. When the power output of the coal-fired cogeneration unit is greater than the demand, it enters the heat storage stage; when the power output of the coal-fired power generation unit is less than the demand, it enters the energy release stage.
[0018] Heat storage stage: The excess electric energy of the generator 5 is output to the built-in electric heater 20, which converts the electric energy into heat energy and stores it in the dry rock. A temperature acquisition device 22 is provided inside the adiabatic storage device 21, and heat storage is automatically stopped when the temperature reaches the upper limit of heat storage 800°C. At this time, the electric regulating valve c17 and the electric regulating valve d18 are closed, and the booster pump d14 stops operating.
[0019] Energy release process: booster pump d14, electric regulating valve c17 and electric regulating valve d18 are turned on. Part of the condensate from the outlet of the heating network circulating water pump c12 is pressurized by the electric regulating valve b16 and booster pump d14 and enters the external coil heat exchanger 19. After absorbing heat and rising in temperature, it passes through the electric regulating valve d18 and enters the outlet of the heating network heater 13, and is supplied to users through the heating network pipeline.
[0020] During the energy release process, the temperature of the dry rock continues to decrease, and the temperature of the heat network circulating water at the outlet of the external coil heat exchanger 19 decreases accordingly. The internal temperature of the heat insulation storage device 21 is obtained by the temperature acquisition device 22, and the heatable water flow rate is calculated. The water flow entering the coil heat exchanger 19 is adjusted by adjusting the frequency of the booster pump d14, so that the heat network circulating water temperature at the outlet of the external coil heat exchanger 19 is the same as the outlet water temperature of the heat network heater 13.
[0021] Beneficial Effects
[0022] The purpose of the present invention is to provide a heat storage system that uses a medium with low cost, low carbon and environmental protection, and excellent heat storage and heat exchange performance, and is applied to the residential heat supply scenario under the deep peak regulation conditions of the cogeneration unit. In the heat storage stage, the electric heating device is operated to convert the electrical energy at the generator outlet into thermal energy and store it in dry rocks. In the energy release stage, part of the heat network circulating water of the heating system enters the coil heat exchanger arranged outside the dry rock, and enters the heat network circulating water after absorbing heat, reducing the steam extraction flow of the low-pressure cylinder, while ensuring the electrical output of the cogeneration unit, while increasing the heating supply. The heat storage medium of this patent is low-carbon and environmentally friendly throughout the process, has excellent heat storage and thermal conductivity, is low-cost, and is easy to obtain. It is an effective way for the cogeneration unit to improve the level of thermal and electric decoupling, solve the contradiction between the deep peak regulation of coal-fired power units and the stable heating supply for residents, and has broad application prospects.
Claims
1. A dry rock heat storage system coupled with a coal-fired cogeneration unit, characterized in that: The invention comprises a boiler (1), a high-pressure cylinder a (2), an intermediate-pressure cylinder b (3), a low-pressure cylinder c (4), a generator (5), a condenser (6), a condensate pump a (7), a low-pressure heater group (8), a deaerator (9), a feed pump b (10), a high-pressure heater group (11), a heat network circulating water pump c (12), a heat network heater (13), a booster pump d (14), an electric regulating valve a (15), an electric regulating valve b (16), an electric regulating valve c (17), an electric regulating valve d (18), an external coil heat exchanger (19), a built-in electric heater (20), an adiabatic storage device (21) and a temperature collection device (22), wherein the main steam-water circulation process is as follows: boiler (1), high-pressure cylinder a (2), boiler (1), intermediate-pressure cylinder b (3), low-pressure cylinder c (4), condenser (6), condensate pump a (7), low-pressure heater group (8), deaerator (9), feed pump b (10), high-pressure heater group (11), The heat supply system (11) returns to the boiler (1). The steam and water flow of the heating system is as follows: the low-pressure cylinder extraction steam enters the heating network heater (13) through the electric regulating valve a (15), heats the heating network circulating water and returns to the condenser (6) through the electric regulating valve b (16). After the heating network circulating water passes through the heating network circulating water pump c (12), the internal temperature of the adiabatic storage device (21) is obtained by the temperature acquisition device (22), and the amount of water that can be heated is calculated. The calculated amount of water passes through the electric regulating valve c (17) and the booster pump d (14) and enters the adiabatic storage device (21). After being heated by the external coil heat exchanger (19), it passes through the electric regulating valve d (18) and enters the outlet end of the heating network heater (13), and is supplied to users through the heating network pipeline. The water obtained by deducting the above-calculated amount of water that can be heated from the total water volume enters the heating network heater (13), is heated by the low-pressure cylinder extraction steam, and enters the outlet end of the heating network heater (13), and is supplied to users through the heating network pipeline.
2. A dry rock heat storage system coupled to a coal-fired cogeneration unit according to claim 1, characterized in that The structure of the heat storage system is as follows: an external coil heat exchanger (19) is installed inside the adiabatic storage device (21); internal electric heaters (20) are evenly arranged at equal intervals inside the external coil heat exchanger (19); the gap between the external coil heat exchanger (19) and the internal electric heater (20) is filled with dry rocks; the internal electric heater (20) can heat the dry rocks inside; the external coil heat exchanger (19) can realize heat exchange between circulating water of the heat network and the dry rocks; and the generator (5) supplies power to the internal electric heater (20) through a cable.
3. A dry rock heat storage system coupled with a coal-fired cogeneration unit according to claim 1, characterized in that: The system operation process is divided into two stages: heat storage and energy release. In the energy release process: the booster pump d (14), the electric regulating valve c (17) and the electric regulating valve d (18) are turned on, and part of the condensate from the outlet of the heat network circulating water pump c (12) is pressurized by the electric regulating valve c (17) and the booster pump d (14) and enters the external coil heat exchanger (19). After absorbing heat and heating, it passes through the electric regulating valve d (18) and enters the outlet of the heat network heater (13) and is supplied to users through the heat network pipeline. In the energy release process, the temperature of the dry rock is continuously reduced, and the internal temperature of the adiabatic storage device (21) is obtained through the temperature acquisition device (22). The flow rate of water that can be heated is calculated, and the frequency of the booster pump d (14) is adjusted to adjust the water flow rate entering the external coil heat exchanger (19), so that the temperature of the heat network circulating water at the outlet of the external coil heat exchanger (19) is the same as the outlet water temperature of the heat network heater (13).