A peak-shifting heating system using thermal storage technology in a thermal power plant

Abstract

The utility model discloses a thermal power plant heat storage process peak-shifting heating system, which relates to the field of thermal power plant heating technology, including a unit of the thermal power plant, a desalted water tank arranged at one side of the unit and used to supply chemical replenishment water to the unit at night, and a hot water tank arranged at one side of the desalted water tank and used to supply chemical replenishment water to the unit during the day, wherein the cooling desalted water after cooling and heat exchange is sent into the hot water tank through a pipeline in the unit, a back pressure machine for heating the steam of the cooling desalted water is arranged between the unit and the hot water tank, and a deaerator is arranged between the hot water tank and the unit. The utility model can store the excess heat generated by the thermal power plant when the heating load is reduced through the heat storage and heat supply of the hot water tank and other components, and can transport the stored heat when the heating load is large and the thermal power plant cannot meet the heating requirements, thereby adapting to the change of the heating load under the condition of stable power generation load, so that the unit can also operate stably under low load conditions.

Description

Technical Field

[0001] The utility model relates to the technical field of heat supply in thermal power plants, in particular to a peak-shifting heat supply system of a thermal power plant with a heat storage process. Background Art

[0002] At present, all countries in the world are encouraging the development of cogeneration, and the development of small and medium-sized thermal power plants in my country is also very rapid. Thermal power plants have greatly improved their comprehensive energy utilization efficiency by following the principle of "heat determines electricity", which not only saves energy but also is beneficial to the environment, and thus has been rapidly developed.

[0003] However, the heat load that plays a decisive role in the operation of thermal power plants often has great fluctuations, especially for thermal power plants with a relatively small proportion of industrial load or with centralized supply of domestic hot water in cities. The load changes more during the peak and valley heating periods in severe cold seasons. This not only affects the stable operation of the unit, reduces efficiency and increases unsafe factors, but also is likely to increase a large amount of equipment investment to ensure peak load.

[0004] With respect to the above-mentioned related technologies, the inventor believes that the thermal load of a thermal power plant differs greatly between night and day, and the unit cannot operate stably under low-load conditions. Therefore, the present application proposes a peak-shifting heating system using a thermal storage process for a thermal power plant. Utility Model Content

[0005] Aiming at the disadvantage that the thermal load of thermal power plants differs greatly between night and day, and the units cannot operate stably under low load conditions, the utility model provides a peak-shifting heating system of thermal power plants using heat storage technology. The specific technical scheme is as follows:

[0006] A thermal power plant heat storage process peak-shifting heating system comprises a unit of the thermal power plant, a desalted water tank arranged at one side of the unit and used for supplying chemical make-up water to the unit at night, and a hot water tank arranged at one side of the desalted water tank and used for supplying chemical make-up water to the unit during the day. The unit sends the cooled desalted water after cooling and heat exchange into the hot water tank through a pipeline, a back pressure machine for heating the cooled desalted water steam is arranged between the unit and the hot water tank, a deaerator is arranged between the hot water tank and the unit, a hot water pump is arranged on one side of the hot water tank and used for sending the high-temperature desalted water in the hot water tank into the deaerator during the day, and the deaerator sends the high-temperature desalted water after deoxygenation into the unit through a pipeline.

[0007] By adopting the above technical solution, through the heat storage and heat supply of components such as hot water tanks, the excess heat generated by the thermal power plant can be stored when the heating load is reduced, and when the heating load is large and the thermal power plant cannot meet the heating requirements, the stored heat can be transported out, thereby adapting to changes in the heating load under the condition of stable power generation load.

[0008] Optionally, a plurality of heat exchangers for heat exchange are provided on one side of the hot water tank, a condensate tank for recovering condensate from the heat exchanger is provided between the outer sides of the plurality of heat exchangers, and a steam drainage lift pump for delivering condensate into the hot water tank is provided on one side of the condensate tank.

[0009] By adopting the above technical solution, the condensate water tank can recycle the water condensed on the heat exchanger.

[0010] Optionally, an anti-radiation layer is fixedly provided on the outer wall of the hot water tank, a protective layer is fixedly provided on the outer wall of the anti-radiation layer, a motor is provided on the top of the hot water tank, a fixing plate is fixedly provided between the outer wall of the protective layer of the hot water tank and the motor, a rotating rod coaxial with the hot water tank is fixedly provided on the bottom of the output end of the motor, the rotating rod is rotatably connected in the hot water tank, and a stirring blade is fixedly provided on the bottom end of the rotating rod for stirring the desalted water in the hot water tank to eliminate temperature differences.

[0011] By adopting the above technical solution, the motor can drive the stirring blades to rotate to stir the desalted water in the hot water tank to eliminate the temperature difference between the upper and lower layers, so that the unit can be heated evenly when supplied with high-temperature desalted water.

[0012] Optionally, a cleaning mechanism for cleaning the top part of the hot water tank is provided at the top of the rotating rod, and the cleaning mechanism includes a cleaning rod fixed to the outer wall of the top of the rotating rod, and a plurality of bristles fixed to the bottom of the cleaning rod and cooperating with the protective layer.

[0013] By adopting the above technical solution, the motor can also drive the cleaning mechanism to rotate to partially clean the top of the hot water tank, thereby reducing the difficulty and intensity of people's cleaning of the top of the hot water tank at a later time.

[0014] In summary, the present invention has at least one of the following beneficial effects:

[0015] 1. Through the heat storage and heat supply of components such as hot water tanks, the excess heat generated by the thermal power plant can be stored when the heating load is reduced. When the heating load is large and the thermal power plant cannot meet the heating requirements, the stored heat can be transported out, thereby adapting to changes in the heating load under the condition of stable power generation load, so that the unit can operate stably under low load conditions.

[0016] 2. Driven by a motor, the stirring blades can be driven to rotate to stir the desalted water in the hot water tank to eliminate the temperature difference between the upper and lower layers, so that the unit can be heated evenly when supplied with high-temperature desalted water. The motor can also drive the cleaning mechanism to rotate to partially clean the top of the hot water tank, reducing the difficulty and intensity of people's later cleaning of the top of the hot water tank, which is convenient and practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0018] Figure 2 It is a schematic diagram of the interior of the hot water tank of the utility model;

[0019] Figure 3 The utility model Figure 2 A magnified view of the structure in the middle.

[0020] Explanation of the reference numerals: 1. Unit; 2. Desalted water tank; 3. Hot water tank; 31. Radiation protection layer; 32. Protective layer; 4. Hot water pump; 5. Deaerator; 6. Back pressure machine; 7. Heat exchanger; 71. Condensate tank; 72. Steam drain lift pump; 8. Motor; 81. Rotating rod; 82. Stirring blade; 83. Fixed plate; 84. Cleaning rod; 85. Brush. DETAILED DESCRIPTION

[0021] The following is combined with Figure 1-3 The utility model is described in further detail.

[0022] The utility model embodiment discloses a thermal power plant heat storage process peak heating system, referring to Figure 1 , including a unit 1 of a thermal power plant, a desalted water tank 2 arranged at one side of the unit 1 and used for supplying chemical make-up water to the unit 1 at night, and a hot water tank 3 arranged at one side of the desalted water tank 2 and used for supplying chemical make-up water to the unit 1 during the day. The desalted water tank 2 can supply cooling desalted water to the unit 1 for cooling during the day.

[0023] Reference Figure 1 The cooling desalted water after cooling and heat exchange is sent to the hot water tank 3 through the pipeline in the unit 1. A back pressure machine 6 for heating the cooling desalted water steam is arranged between the unit 1 and the hot water tank 3. When the external heat load is low at night, the desalted water used as cooling water for cooling the unit 1 will return to the hot water tank 3. Due to the heat exchange of the cooling water, the cooling water temperature will increase, thereby increasing the water temperature in the hot water tank 3, and the desalted water is heated to about 90°C by the steam of the back pressure machine 6, so as to store the excess heat generated by the thermal power plant in the hot water tank 3 when the heating load is reduced (at this time, the unit 1 makeup water is all supplied by the desalted water tank 2).

[0024] Reference Figure 1 A deaerator 5 is provided between the hot water tank 3 and the unit 1. A hot water pump 4 is provided on one side of the hot water tank 3 for delivering the high-temperature desalted water in the hot water tank 3 into the deaerator 5 during the day. The deaerator 5 delivers the deoxygenated high-temperature desalted water into the unit 1 through a pipeline. When the external heat load rises during the day, the hot water pump 4 is used to deliver the high-temperature desalted water in the hot water tank 3 to the deaerator 5 for deoxygenation. The deoxygenated high-temperature desalted water can be delivered to the unit 1 to transport the heat stored in the hot water tank 3 when the heating load is large and the thermal power plant cannot meet the heating requirements (at this time, the make-up water of the unit 1 is all supplied by the hot water tank 3, and the desalted water tank 2 mainly supplies cooling water for the unit 1).

[0025] Reference Figure 1 A plurality of heat exchangers 7 for heat exchange are provided on one side of the hot water tank 3. The heat exchanger 7 can exchange heat between the water in the hot water tank 3 and hot water in other external machines, thereby increasing the water temperature in the hot water tank 3. Condensation water tanks 71 for recovering condensed water from the heat exchangers 7 are provided between the outer sides of the plurality of heat exchangers 7. The condensation water tank 71 can recover water condensed on the heat exchanger 7.

[0026] Reference Figure 1 A steam drain lift pump 72 for delivering condensed water into the hot water tank 3 is provided on one side of the condensed water tank 71. After the recovered condensed water enters the hot water tank 3 through the steam drain lift pump 72, it can replenish the water in the hot water tank 3 and reduce the waste of water resources.

[0027] Reference Figure 1-2 An anti-radiation layer 31 is fixedly provided on the outer wall of the hot water tank 3, and a protective layer 32 is fixedly provided on the outer wall of the anti-radiation layer 31. The anti-radiation layer 31 can be an aluminum foil cloth, which can reduce the thermal radiation of the hot water tank 3, thereby keeping the hot water tank 3 warm. The protective layer 32 can be an aluminum sheet, which can protect the hot water tank 3.

[0028] Reference Figure 1-2 A motor 8 is provided on the top of the hot water tank 3, and a fixing plate 83 is fixed between the outer wall of the protective layer 32 of the hot water tank 3 and the motor 8. The fixing plate 83 can connect the hot water tank 3 and the motor 8 and support the motor 8.

[0029] Reference Figure 1-2 A rotating rod 81 coaxial with the hot water tank 3 is fixedly provided at the bottom of the output end of the motor 8. The rotating rod 81 is rotatably connected to the hot water tank 3. When the motor 8 is running, it will drive the rotating rod 81 to rotate.

[0030] Reference Figure 1-2 A stirring blade 82 is fixedly disposed at the bottom end of the rotating rod 81 for stirring the desalted water in the hot water tank 3 to eliminate the temperature difference. When the rotating rod 81 rotates, the stirring blade 82 will be driven to rotate. When the stirring blade 82 rotates, the desalted water in the hot water tank 3 can be stirred to eliminate the temperature difference between the upper and lower layers of the desalted water, so that the unit 1 can be heated evenly when supplied with high-temperature desalted water.

[0031] Reference Figure 2-3 A cleaning mechanism for cleaning the top part of the hot water tank 3 is provided at the top of the rotating rod 81. The cleaning mechanism includes a cleaning rod 84 fixedly arranged on the outer wall of the top end of the rotating rod 81, and a plurality of bristles 85 fixedly arranged on the bottom of the cleaning rod 84 and cooperating with the protective layer 32. When the rotating rod 81 rotates, the cleaning rod 84 and the bristles 85 are driven to rotate accordingly. When the bristles 85 rotate, they can brush away foreign matter such as dust on the top of the hot water tank 3, thereby cleaning the top part of the hot water tank 3.

[0032] The implementation principle of a thermal power plant heat storage process peak-shifting heating system according to the embodiment of the utility model is:

[0033] When the external heat load is low at night, the desalted water used as cooling water for unit 1 will return to the hot water tank 3. Due to the heat exchange of the cooling water, the cooling water temperature will increase, thereby increasing the water temperature in the hot water tank 3, and the desalted water will be heated to about 90°C by the steam of the back pressure machine 6 to store the excess heat generated by the thermal power plant in the hot water tank 3 when the heating load is reduced (at this time, the make-up water of unit 1 is all supplied by the desalted water tank 2);

[0034] When the external heat load rises during the day, the hot water pump 4 is used to send the high-temperature desalted water in the hot water tank 3 to the deaerator 5 for deoxygenation. The high-temperature desalted water after deoxygenation can be sent to the unit 1 to transport the heat stored in the hot water tank 3 when the heating load is large and the thermal power plant cannot meet the heating requirements (at this time, the make-up water of the unit 1 is all supplied by the hot water tank 3, and the desalted water tank 2 mainly supplies cooling water for the unit 1), thereby realizing heat storage and peak-shifting heating for the thermal power plant.

[0035] The above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. Although the utility model is described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions recorded in the above embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A thermal power plant heat storage process peak-shifting heating system, comprising a unit (1) of the thermal power plant, a desalted water tank (2) disposed on one side of the unit (1) and used to supply chemical make-up water to the unit (1) at night, and a hot water tank (3) disposed on one side of the desalted water tank (2) and used to supply chemical make-up water to the unit (1) during the day, characterized in that: The unit (1) delivers the cooled desalted water after cooling and heat exchange into the hot water tank (3) through a pipeline. A back pressure machine (6) for heating the steam of the cooled desalted water is provided between the unit (1) and the hot water tank (3). A deaerator (5) is provided between the hot water tank (3) and the unit (1). A hot water pump (4) for delivering the high-temperature desalted water in the hot water tank (3) into the deaerator (5) during the day is provided on one side of the hot water tank (3). The deaerator (5) delivers the high-temperature desalted water after deoxygenation into the unit (1) through a pipeline.

2. The peak-shifting heating system of thermal power plant heat storage process according to claim 1, characterized in that: A plurality of heat exchangers (7) for heat exchange are provided on one side of the hot water tank (3), and a condensate water tank (71) for recovering condensate water from the heat exchanger (7) is provided between the outer sides of the plurality of heat exchangers (7).

3. A thermal power plant heat storage process peak-shifting heating system according to claim 2, characterized in that: A steam drain lift pump (72) for delivering condensate into the hot water tank (3) is provided on one side of the condensate tank (71).

4. The thermal power plant heat storage process peak-shifting heating system according to claim 1, characterized in that: The outer wall of the hot water tank (3) is fixedly provided with a radiation protection layer (31), and the outer wall of the radiation protection layer (31) is fixedly provided with a protective layer (32).

5. The peak-shifting heating system of thermal power plant heat storage process according to claim 4 is characterized by: A motor (8) is provided on the top of the hot water tank (3), and a fixing plate (83) is fixedly provided between the outer wall of the protective layer (32) of the hot water tank (3) and the motor (8).

6. A thermal power plant heat storage process peak-shifting heating system according to claim 5, characterized in that: A rotating rod (81) coaxial with the hot water tank (3) is fixedly provided at the bottom of the output end of the motor (8), and the rotating rod (81) is rotatably connected inside the hot water tank (3).

7. The thermal power plant heat storage process peak-shifting heating system according to claim 6, characterized in that: A stirring blade (82) is fixedly provided at the bottom end of the rotating rod (81) for stirring the desalted water in the hot water tank (3) to eliminate temperature differences.

8. The thermal power plant heat storage process peak-shifting heating system according to claim 7, characterized in that: A cleaning mechanism for cleaning the top portion of the hot water tank (3) is provided at the top of the rotating rod (81), the cleaning mechanism comprising a cleaning rod (84) fixed to the outer wall of the top of the rotating rod (81), and a plurality of bristles (85) fixed to the bottom of the cleaning rod (84) and in contact with the protective layer (32).

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