Energy storage peak regulation system of high-pressure hot water gas-fired boiler coupled coal-fired unit

Abstract

The utility model relates to the technical field of energy storage and peak regulation, in particular to an energy storage and peak regulation system of a high-pressure hot water gas-fired boiler coupled coal-fired unit. When the load of the coal-fired unit is reduced, the control part receives load reduction signals of the steam turbine unit and the generator and sends signals to the bypass water pump and the electric heater, the output of the bypass water pump is increased, and high-pressure hot water in the boiler water loop is pumped into the high-pressure hot water energy storage unit through the one-way throttle valve so as to reduce the evaporation capacity in the steam turbine unit; when the load of the coal-fired unit is increased, the control part receives load increasing signals of the steam turbine unit and the power generator and sends signals to the fuel part, so that the flow of gas fuel is increased, and the gas fuel enters a combustor through a gas fuel inlet pipeline; the heat exchange pipeline in the boiler barrel is used for conducting heat exchange on high-pressure hot water stored in the high-pressure hot water energy storage unit to generate steam, and the steam is introduced into the steam turbine unit to rapidly supplement high-pressure steam needed by load rising. According to the technical scheme, the change of the load can be quickly responded.

Description

Technical Field

[0001] This utility model relates to the field of energy storage and peak shaving technology, and in particular to an energy storage and peak shaving system for a high-pressure hot water gas boiler coupled with a coal-fired power unit. Background Technology

[0002] The large-scale integration of wind and solar renewable energy is of great significance for building a new power system; however, the volatility and randomness of wind and solar power generation pose a significant challenge to the power system. Rapid peak shaving by coal-fired units is a key technology for ensuring grid stability.

[0003] When coal-fired power plants participate in peak shaving, their main operating mode is to adjust the unit's load to match the grid's power demand. Load changes are generally achieved by altering the furnace heat load to adjust steam flow, which in turn adjusts the turbine's work output. Furnace heat load changes are primarily achieved by adjusting the coal mill output to regulate the coal milling rate and feed rate. However, adjusting the load by changing the coal supply rate has significant inertia, requiring a long time and resulting in a slow response to load fluctuations, making it difficult to adapt to the rapid changes in wind and solar renewable energy supply.

[0004] Therefore, there is an urgent need to provide an energy storage and peak-shaving system for high-pressure hot water gas boiler coupled with coal-fired power unit to solve the above-mentioned technical problems. Summary of the Invention

[0005] To achieve rapid response to load changes, this utility model provides an energy storage and peak-shaving system for a high-pressure hot water gas boiler coupled with a coal-fired power unit.

[0006] This utility model embodiment provides an energy storage and peak-shaving system for a high-pressure hot water gas boiler coupled with a coal-fired power unit, comprising:

[0007] The steam generating section includes a furnace, a superheater, and a boiler water circuit disposed around the furnace. The superheater is used to heat the saturated steam in the boiler water circuit into superheated steam.

[0008] The power generation section includes a steam turbine unit and a generator connected in sequence, with the inlet end of the steam turbine unit connected to the superheater;

[0009] The energy storage section includes a high-pressure hot water energy storage unit and a steam-water separator connected in sequence. A bypass water pump and a one-way throttle valve are connected between the high-pressure hot water energy storage unit and the boiler water circuit. The high-pressure hot water energy storage unit is used to store high-pressure hot water in the boiler water circuit. The outlet end of the steam-water separator is connected to a separation gas path and a separation water path, respectively. The separation gas path is connected to the steam turbine unit, and the separation water path is connected to the boiler water circuit.

[0010] The gas-fired boiler section includes a burner and a boiler drum connected in sequence. The boiler drum is equipped with heat exchange pipes. The inlet end of the heat exchange pipes is connected to the high-pressure hot water storage unit, and the outlet end is connected to the steam-water separator.

[0011] The fuel section includes a gaseous fuel storage tank and a gaseous fuel inlet pipe connected in sequence. The outlet end of the gaseous fuel inlet pipe is connected to the burner, and the gaseous fuel storage tank is used to store gaseous fuel.

[0012] The electric heating section includes a power transmission line and an electric heater. The power transmission line is connected to the generator and the electric heater respectively. The electric heater is used to supply heat to the high-pressure hot water energy storage unit.

[0013] The control unit is electrically connected to the turbine unit, the generator, the bypass water pump, the fuel section, and the electric heater, respectively. The control unit is used to control the output of the bypass water pump, the flow rate of the gaseous fuel, and the heating amount of the electric heater based on the flow rate, temperature, and pressure of the steam and water in the turbine unit and the power of the generator.

[0014] This utility model provides an energy storage and peak-shaving system for a high-pressure hot water gas-fired boiler coupled with a coal-fired power unit. When the coal-fired power unit reduces its load, the control unit receives a signal indicating a decrease in the load of the turbine and generator, and sends a signal to the bypass water pump and electric heater. The bypass water pump increases its output, pumping the high-pressure hot water in the boiler water circuit through a one-way throttle valve into the high-pressure hot water energy storage unit to reduce the evaporation in the turbine. At the same time, the generator sends part of its electrical energy to the electric heater via the transmission line to supply heat to the high-pressure hot water energy storage unit for heat preservation and storage. When the coal-fired power unit increases its load, the control unit receives a signal indicating an increase in the load of the turbine and generator, and sends a signal to the fuel unit to increase the flow rate of gaseous fuel. The gaseous fuel flows through the gaseous fuel inlet pipe to the burner, where it changes from a standby flame state to a stable combustion state. The high-pressure hot water stored in the high-pressure hot water energy storage unit is then exchanged with heat through the heat exchange pipes in the boiler drum to generate steam. After steam-water separation by a steam-water separator, the steam is fed into the turbine to quickly replenish the high-pressure steam required for load increase. Therefore, the above technical solution can achieve rapid response to load changes. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the structure of an energy storage and peak-shaving system for a high-pressure hot water gas boiler coupled with a coal-fired power unit, provided in one embodiment of this utility model.

[0017] Figure 2 This is a schematic diagram of the structure of an energy storage and peak-shaving system for a high-pressure hot water gas boiler coupled with a coal-fired power unit, provided in another embodiment of this utility model.

[0018] Figure label:

[0019] 1-Steam generating section;

[0020] 11-Furnace chamber;

[0021] 12-Superheater;

[0022] 13-Boiler water circuit;

[0023] 131-Steam drum;

[0024] 132 - Downcomer;

[0025] 133 - Lower connector;

[0026] 134 - Water-cooled wall;

[0027] 135 - Top header box;

[0028] 136 - Boiler water circulation pump;

[0029] 137 - Evaporator tube;

[0030] 138 - Start the separator;

[0031] 139 - Economizer;

[0032] 2-Power generation section;

[0033] 21-Steam turbine unit;

[0034] 211-High Pressure Cylinder;

[0035] 212 - Medium-pressure cylinder;

[0036] 213 - Low-pressure cylinder;

[0037] 22-Generator;

[0038] 3-Energy storage section;

[0039] 31-Bypass pump;

[0040] 32 - One-way throttle valve;

[0041] 33-High-pressure hot water energy storage unit;

[0042] 331-High-pressure hot water accumulator;

[0043] 332 - Pressure reducing valve;

[0044] 34-Steam-water separator;

[0045] 35 - Separation water pump;

[0046] 36-Flow regulating valve

[0047] 4-Gas-fired boiler section;

[0048] 41-Burner;

[0049] 42-Pot Drum;

[0050] 43-Tail flue;

[0051] 5-Fuel section;

[0052] 51-Gas fuel storage tank;

[0053] 52 - Gas fuel inlet pipe;

[0054] 53-Pyrolysis Furnace;

[0055] 6-Electric heating section;

[0056] 61-Transmission lines;

[0057] 62-Electric heater;

[0058] 7-Control section. Detailed Implementation

[0059] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0060] like Figure 1 and Figure 2 As shown, this utility model embodiment provides an energy storage and peak-shaving system for a high-pressure hot water gas-fired boiler coupled with a coal-fired power unit. The system includes a steam generation section 1, a power generation section 2, an energy storage section 3, a gas-fired boiler section 4, a fuel section 5, an electric heating section 6, and a control section 7, wherein:

[0061] The steam generating section 1 includes a furnace 11, a superheater 12, and a boiler water circuit 13 disposed around the furnace 11. The superheater 12 is used to heat the saturated steam in the boiler water circuit 13 into superheated steam.

[0062] The power generation section 2 includes a steam turbine unit 21 and a generator 22 connected in sequence, with the inlet end of the steam turbine unit 21 connected to the superheater 12;

[0063] The energy storage section 3 includes a high-pressure hot water energy storage unit 33 and a steam-water separator 34 connected in sequence. A bypass water pump 31 and a one-way throttle valve 32 are connected between the high-pressure hot water energy storage unit 33 and the boiler water circuit 13. The high-pressure hot water energy storage unit 33 is used to store high-pressure hot water in the boiler water circuit 13. The outlet end of the steam-water separator 34 is connected to a separation gas path and a separation water path respectively. The separation gas path is connected to the steam turbine unit 21, and the separation water path is connected to the boiler water circuit 13.

[0064] The gas boiler section 4 includes a burner 41 and a boiler drum 42 connected in sequence. The boiler drum 42 is equipped with a heat exchange pipeline. The inlet end of the heat exchange pipeline is connected to the high-pressure hot water storage unit 33, and the outlet end is connected to the steam-water separator 34.

[0065] The fuel section 5 includes a gaseous fuel storage tank 51 and a gaseous fuel inlet pipe 52 connected in sequence. The outlet end of the gaseous fuel inlet pipe 52 is connected to the burner 41. The gaseous fuel storage tank 51 is used to store gaseous fuel.

[0066] The electric heating section 6 includes a power transmission line 61 and an electric heater 62. The power transmission line 61 is connected to the generator 22 and the electric heater 62 respectively. The electric heater 62 is used to supply heat to the high-pressure hot water energy storage unit 33.

[0067] The control unit 7 is electrically connected to the turbine unit 21, generator 22, bypass water pump 31, fuel section 5 and electric heater 62 respectively. The control unit 7 is used to control the output of bypass water pump 31, the flow rate of gaseous fuel and the heating amount of electric heater 62 according to the flow rate, temperature and pressure of steam and water in turbine unit 21 and the power of generator 22, so as to realize rapid response to load changes of coal-fired unit.

[0068] A gas flow control device is installed between the gas fuel storage tank 51 and the gas fuel inlet pipe 52. The control part 7 is connected to the gas flow control device, which is used to control the output flow of the gas fuel.

[0069] In this embodiment, when the coal-fired unit reduces its load, the control unit 7 receives a signal that the load of the turbine unit 21 and the generator 22 has decreased, and sends a signal to the bypass water pump 31 and the electric heater 72. The bypass water pump 31 increases its output and pumps the high-pressure hot water in the boiler water circuit 13 into the high-pressure hot water storage unit 33 through the one-way throttle valve 32 to reduce the evaporation in the turbine unit 21. At the same time, the generator 22 sends part of the electrical energy to the electric heater 62 through the transmission line 61 to supply heat to the high-pressure hot water storage unit 33 to achieve heat preservation and storage.

[0070] When the coal-fired unit increases its load, the control section 7 receives the signal that the load of the turbine unit 21 and the generator 22 has increased, and sends a signal to the fuel section 5 to increase the flow rate of gaseous fuel. The gaseous fuel goes through the gaseous fuel inlet pipe 52 to the burner 41. The burner 41 changes from the standby flame state to the stable combustion state, so as to use the heat exchange pipe in the boiler drum 42 to exchange heat with the high-pressure hot water stored in the high-pressure hot water storage unit 33 to generate steam. After the steam is separated by the steam-water separator 34, the steam is introduced into the turbine unit 21 to quickly replenish the high-pressure steam required for increasing the load. The flue gas generated by the combustion of the gas boiler section 4 is discharged into the tail flue of the coal-fired boiler through the tail flue 43 to heat the economizer.

[0071] It should be noted that by setting up the steam-water separator 34, not only can the separated steam be sent to the turbine unit 21 to do work, but it can also prevent water erosion of the turbine unit 21 to ensure the safe and stable operation of the turbine unit 21. In addition, the separated steam can be circulated back to the economizer of the coal-fired boiler through the separation water circuit and the separation water pump 35, thereby saving water consumption.

[0072] In one embodiment of the present invention, the turbine unit 21 includes a high-pressure cylinder 211, an intermediate-pressure cylinder 212 and a low-pressure cylinder 213 connected in sequence. The high-pressure cylinder 211 is connected to the superheater 12 and the low-pressure cylinder 213 is connected to the generator 22.

[0073] In one embodiment of this utility model, when the furnace 11 is a drum boiler, the boiler water circuit 13 includes a steam drum 131, a downcomer 132, a lower header 133, a water-cooled wall 134, and an upper header 135 connected in sequence. The downcomer 132 is equipped with a boiler water circulation pump 136. The top of the upper header 135 is connected to the superheater 12. The high-pressure hot water storage unit 33 is connected to the downcomer 132. The downcomer 132 is connected to the bypass pump 31. When the furnace 11 is a once-through boiler, the boiler water circuit 13 includes an evaporator 137, a start-up separator 138, and a boiler water circulation pump 136 connected in sequence. The boiler water circuit 13 also includes an economizer 139. The top of the start-up separator 138 is connected to the superheater 12. The high-pressure hot water storage unit 33 is connected to the outlet of the economizer 139. The economizer 139 is connected to the bypass pump 31.

[0074] In this embodiment, for a drum boiler, the amount of evaporating water in the boiler water circuit 13 can be reduced by connecting the high-pressure hot water storage unit 33 to the downcomer 132, and for a once-through boiler, the amount of evaporating water can be reduced by connecting the high-pressure hot water storage unit 33 to the economizer outlet 139.

[0075] In one embodiment of the present invention, the high-pressure hot water storage unit 33 includes a high-pressure hot water accumulator 331 and a pressure reducing valve 332 connected in sequence. For a steam drum boiler, the high-pressure hot water accumulator 331 is connected in sequence to a one-way throttle valve 32, a bypass pump 31 and a downcomer 132. For a once-through boiler, the high-pressure hot water accumulator 331 is connected in sequence to a one-way throttle valve 32, a bypass pump 31 and an economizer 139. The inlet end of the steam-water separator 34 is connected to the boiler drum 42.

[0076] In this embodiment, for a drum boiler, a high-pressure hot water accumulator 331 can be installed to store high-pressure hot water from the downcomer 132; for a once-through boiler, high-pressure hot water from the economizer 139 can be stored. By installing a pressure reducing valve 332, when the coal-fired unit needs to increase its load, the flow and pressure of the high-pressure hot water from the high-pressure hot water accumulator 331 can be controlled. After the pressure is reduced by the pressure reducing valve 332, part of the high-pressure hot water flashes into steam. The steam-water mixture comes to the boiler drum 42 of the gas-fired boiler, and after heat exchange in the boiler drum 42, steam is generated. After the steam-water separator 34 separates the steam and water, the steam that meets the parameters is sent to the turbine unit 21 to do work. In addition, the pressure reducing valve 332 can also be used in conjunction with the bypass pump 31 to provide the power required for fluid flow.

[0077] In some embodiments, the high-pressure hot water accumulator 331 is made of thermal insulation material (e.g., aluminum silicate + rock wool board), which makes the energy dissipation of the high-pressure hot water stored inside it smaller, so as to always maintain a high temperature and high pressure state.

[0078] To further ensure that the energy dissipation of the high-pressure hot water stored inside the high-pressure hot water accumulator 331 is minimized, active insulation or active heating of the high-pressure hot water inside the high-pressure hot water accumulator 331 can be considered.

[0079] In one embodiment of this utility model, the electric heating part 6 includes a power transmission line 61 and an electric heater 62. When the coal-fired unit reduces its load, the generator 22 sends part of the electrical energy to the electric heater 62 through the power transmission line 61 to heat and keep warm the high-pressure hot water stored in the high-pressure hot water accumulator 331.

[0080] In one embodiment of this utility model, for a drum boiler, the energy storage section 3 further includes a separator pump 35. For a drum boiler, the downcomer 132, high-pressure hot water accumulator 331, steam-water separator 34 and bypass pump 32 are connected in sequence. The hot water pressure in the high-pressure hot water accumulator 331 is greater than the hot water pressure in the downcomer 132. For a once-through boiler, the economizer 139, high-pressure hot water accumulator 331, steam-water separator 34 and bypass pump 32 are connected in sequence. The hot water pressure in the high-pressure hot water accumulator 331 is greater than the hot water pressure in the economizer 139.

[0081] In this embodiment, by setting up a bypass water pump 31, for a steam drum boiler, it can pressurize the high-pressure hot water from the downcomer 132 to prevent it from vaporizing into steam, and also provide power by sending the high-pressure hot water from the downcomer 132 to the high-pressure hot water accumulator 331 for storage. For a once-through boiler, it can pressurize the high-pressure hot water from the economizer 139 to prevent it from vaporizing into steam, and also provide power by sending the high-pressure hot water from the economizer 139 to the high-pressure hot water accumulator 331 for storage.

[0082] It should be noted that, precisely because of the separation water pump 35, the hot water in the separated water circuit after separation by the steam-water separator 34 can be sent to the deaerator of the coal-fired unit. After being heated by the deaerator and high-pressure heaters of each stage of the coal-fired unit, it is sent to the boiler water circuit 13.

[0083] In one embodiment of this utility model, the separation gas path includes two parallel gas paths, a first gas path and a second gas path. The first gas path is provided with a one-way throttle valve 32, a flow regulating valve 36 and a one-way throttle valve 32 connected in sequence. The second gas path is provided with a one-way throttle valve 32. The opening and closing of the first gas path and the second gas path are related to the steam quantity of the turbine unit 21.

[0084] In this embodiment, when the steam volume of the turbine unit 21 changes rapidly, the steam from the gas separation path after the steam-water separator 34 is directly connected to the turbine unit 21 via the bypass system composed of the one-way throttle valve 32. When the boiler load changes slowly, the steam from the gas separation path after the steam-water separator 34 is regulated to flow to the turbine unit 21 via the regulating passage composed of the one-way throttle valve 32, the flow regulating valve 36, and the one-way throttle valve 32.

[0085] Considering that the parameters (including temperature and pressure) of the steam generated by heating the hot water stored in the high-pressure hot water accumulator 331 match the fluid parameters required by the turbine unit 21, a gas-fired boiler section 4 can be installed after the pressure reducing valve 332. This boiler section heats the hot water stored in the high-pressure hot water accumulator 331 to generate steam with the required parameters before it enters the turbine unit 21 when the coal-fired unit increases its load. For example, if a higher steam temperature is required for the high-pressure cylinder, the gas-fired boiler section 4 can be used to heat part of the steam-water mixture generated by flash evaporation. Conversely, if the steam temperature for the intermediate-pressure and low-pressure cylinders may not need to be too high, the output of the gas-fired boiler section 4 can be adjusted accordingly. Further details are omitted here.

[0086] To heat the hot water stored in the high-pressure hot water accumulator 331, the gas boiler section 4 consists of a burner 41, a boiler drum 42, and a tail flue 43. The burner 41 and the tail flue 43 are connected in sequence to the inlet end of the boiler drum 42, which is connected to the high-pressure hot water accumulator 33, and to the outlet end, which is connected to the steam-water separator 34. The fuel section 5 consists of a gas fuel storage tank 51, a gas fuel inlet pipe 52, and a pyrolysis furnace 53 connected in sequence. The gas fuel in the gas fuel storage tank 51 can be natural gas, hydrogen, ammonia, coke oven gas, blast furnace gas, or other gaseous fuels.

[0087] When the gaseous fuel is hydrogen, the gaseous fuel storage tank 51 can be set up within the power plant area where the coal-fired unit is located. That is, an electrolysis hydrogen production device can be set up within the power plant area, and the electrolysis hydrogen production device can be powered by surplus electricity from wind and solar renewable power generation, plant power or other forms of electricity, thus avoiding increased costs and safety risks caused by long-distance transportation of hydrogen.

[0088] In one embodiment of this utility model, see reference Figure 1 A pyrolysis furnace 53 is installed after the gaseous fuel inlet pipe 52. When the gaseous fuel is ammonia, the ammonia enters the pyrolysis furnace 53 through the gaseous fuel inlet pipe 52, where it undergoes a chemical reaction and is pyrolyzed into combustible gases such as hydrogen. These combustible gases and air then enter the burner 41 for combustion. The installation of the pyrolysis furnace 53 improves the fuel adaptability of the burner 41 and also increases the fuel utilization rate.

[0089] In one embodiment of this utility model, gaseous fuel comes into burner 41 through gaseous fuel inlet pipe 52. When the coal-fired unit is running at a stable load, burner 41 maintains a standby flame and burns a small amount of gaseous fuel to maintain stable operation, thereby reducing the use of gaseous fuel.

[0090] In some embodiments, the heat exchange pipes (i.e. flue pipes) inside the boiler drum 42 are arranged in multiple serpentine or staggered patterns to increase the convective heat exchange between the hot water from the high-pressure hot water accumulator 331 inside the boiler drum 42 and the flue pipes, thereby improving the fuel utilization rate of the burner 41.

[0091] In summary, thermal energy storage technology is one of the important development directions in energy storage technology. Large-capacity thermal energy storage participating in power system peak shaving can improve the energy system's ability to optimize configuration across time and space. As a flexible and controllable load, it can improve the power system's regulation capability. When adjusting the load by changing the steam volume on the steam supply side, thermal energy storage can be used to address the change in steam volume. When the load decreases, the high-pressure hot water in the furnace or the superheated steam at the superheater outlet is stored, thereby reducing the total steam volume to regulate the load. When the load increases, the stored high-pressure hot water or superheated steam is sent back to the steam circuit to replenish the total steam volume. At the same time, by using thermal energy storage, the total energy dissipation during load changes can be minimized.

[0092] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A high-pressure hot water gas-fired boiler coupled with a coal-fired power unit, characterized in that the system... include: The steam generating section (1) includes a furnace (11), a superheater (12), and a boiler water circuit (13) disposed around the furnace (11). The superheater (12) is used to heat the saturated steam in the boiler water circuit (13) into superheated steam. The power generation section (2) includes a steam turbine unit (21) and a generator (22) connected in sequence, with the inlet end of the steam turbine unit (21) connected to the superheater (12); The energy storage section (3) includes a high-pressure hot water energy storage unit (33) and a steam-water separator (34) connected in sequence. A bypass water pump (31) and a one-way throttle valve (32) are connected between the high-pressure hot water energy storage unit (33) and the boiler water circuit (13). The high-pressure hot water energy storage unit (33) is used to store high-pressure hot water in the boiler water circuit (13). The outlet end of the steam-water separator (34) is connected to a separation gas path and a separation water path respectively. The separation gas path is connected to the steam turbine unit (21), and the separation water path is connected to the boiler water circuit (13). The gas boiler section (4) includes a burner (41) and a boiler drum (42) connected in sequence. The boiler drum (42) is equipped with a heat exchange pipeline. The inlet end of the heat exchange pipeline is connected to the high-pressure hot water energy storage unit (33), and the outlet end is connected to the steam-water separator (34). The fuel section (5) includes a gas fuel storage tank (51) and a gas fuel inlet pipe (52) connected in sequence. The outlet end of the gas fuel inlet pipe (52) is connected to the burner (41). The gas fuel storage tank (51) is used to store gas fuel. The electric heating section (6) includes a power transmission line (61) and an electric heater (62). The power transmission line (61) is connected to the generator (22) and the electric heater (62) respectively. The electric heater (62) is used to supply heat to the high-pressure hot water storage unit (33). The control unit (7) is electrically connected to the turbine unit (21), the generator (22), the bypass water pump (31), the fuel section (5), and the electric heater (62), respectively. The control unit (7) is used to control the output of the bypass water pump (31), the flow rate of the gaseous fuel, and the heating amount of the electric heater (62) according to the flow rate, temperature, and pressure of the steam and water in the turbine unit (21) and the power of the generator (22). A gas flow control device is provided between the gas fuel storage tank (51) and the gas fuel inlet pipe (52). The control part (7) is connected to the gas flow control device, which is used to control the output flow of the gas fuel. The gaseous fuel is natural gas, hydrogen, ammonia, coke oven gas, or blast furnace gas; When the gaseous fuel is ammonia, the fuel section (5) also includes a pyrolysis furnace (53) connected to the outlet end of the gaseous fuel inlet pipe (52).

2. The energy storage and peak-shaving system for a high-pressure hot water gas-fired boiler coupled with a coal-fired power unit according to claim 1, characterized in that, When the furnace (11) is a steam drum boiler, the boiler water circuit (13) includes a steam drum (131), a downcomer (132), a lower header (133), a water-cooled wall (134), and an upper header (135) connected in sequence. The downcomer (132) is equipped with a boiler water circulation pump (136). The steam drum (131) is connected to the superheater (12), and the high-pressure hot water energy storage unit (33) is connected to the downcomer (132). When the furnace (11) is a once-through boiler, the boiler water circuit (13) includes an evaporator (137), a start-up separator (138), and a boiler water circulation pump (136) connected end to end in sequence. An economizer (139) is installed on the evaporator (137). The start-up separator (138) is connected to the superheater (12). The high-pressure hot water energy storage unit (33) is connected to the economizer (139).

3. The energy storage and peak-shaving system for a high-pressure hot water gas-fired boiler coupled with a coal-fired power unit according to claim 2, characterized in that, For a steam drum boiler, the downcomer (132) and the bypass pump (31) are connected; For a DC boiler, the economizer (139) and the bypass pump (31) are connected.

4. The energy storage and peak-shaving system for a high-pressure hot water gas-fired boiler coupled with a coal-fired power unit according to claim 3, characterized in that, The high-pressure hot water energy storage unit (33) includes a high-pressure hot water energy storage device (331) and a pressure reducing valve (332) connected in sequence. The high-pressure hot water energy storage device (331) is connected to the one-way throttle valve (32), and the pressure reducing valve (332) is connected to the heat exchange pipeline.

5. The energy storage and peak-shaving system for a high-pressure hot water gas-fired boiler coupled with a coal-fired power unit according to any one of claims 1-4, characterized in that, The separated gas path includes two parallel gas paths, a first gas path and a second gas path. The first gas path is provided with a one-way throttle valve (32), a flow regulating valve (36) and a one-way throttle valve (32) connected in sequence. The second gas path is provided with a one-way throttle valve (32). The opening and closing of the first gas path and the second gas path are related to the steam quantity of the turbine unit (21).

Images