Coal-fired boiler starting system based on fused salt heat storage

Abstract

The invention discloses a coal-fired boiler starting system based on fused salt heat storage. The coal-fired boiler starting system comprises a coal-fired power generation system and a fused salt heat storage and release system. The coal-fired power generation system comprises a boiler evaporator, and the boiler evaporator is provided with a preheating medium outlet and a preheating medium inlet; the molten salt heat storage and release system comprises a molten salt circulation loop and preheating pipelines, the molten salt circulation loop comprises a heat storage device, a high-temperature molten salt tank, a heat exchanger and a low-temperature molten salt tank which are sequentially connected, and the preheating pipelines are connected between the preheating medium outlet and the preheating medium inlet and comprise the first preheating pipeline and the second preheating pipeline. The first preheating pipeline is arranged on the heat storage device and exchanges heat with the heat storage device. The first preheating pipeline is arranged on the heat exchanger and exchanges heat with the heat exchanger. According to the coal-fired boiler starting system based on fused salt heat storage, a large amount of heat is transferred to the steam-water working medium of the boiler in a short time, and the starting speed and efficiency of a coal-fired power generation unit are improved.

Description

Technical Field

[0001] The present invention relates to the field of coal-fired boilers, and more particularly to a start-up system for a coal-fired boiler based on molten salt heat storage. Background Art

[0002] A coal-fired boiler is an energy conversion device, and its main function is to transfer the heat energy released by fuel combustion or other forms of energy to water or other working media to generate steam or hot water. When the coal-fired boiler needs to be started, in order to ensure the safe operation of the boiler, the boiler needs to be preheated, that is, the so-called "warming the pot" and "warming the furnace" steps. However, the current preheating technologies, such as using steam generated by an oil-fired boiler or electric heating, have problems such as high cost and inconvenient operation, resulting in a long preheating time and a slow start-up speed of the boiler. Especially in the two-shift operation mode, these problems are more prominent. Therefore, improvement is needed. Summary of the Invention

[0003] The present invention aims to at least solve one of the technical problems existing in the prior art. For this purpose, an object of the present invention is to provide a start-up system for a coal-fired boiler based on molten salt heat storage. By enabling the preheating medium to exchange heat with the heat storage device in the heat storage device and also to exchange heat with molten salt through a heat exchanger, a large amount of heat can be transferred to the steam-water working medium of the boiler in a short time, shortening the time required for "warming the pot"; the steam-water working medium heated by molten salt can also enter the boiler evaporator through the preheating medium inlet to heat the boiler evaporator, accelerating the "warming the furnace" process, further improving the start-up speed, and significantly enhancing the start-up speed and efficiency of the coal-fired power generation unit; in addition, this technology does not need to rely on expensive fuel oil, has low cost and economy, and does not require steam support from adjacent units, having flexibility.

[0004] The start-up system for a coal-fired boiler based on molten salt heat storage according to an embodiment of the present invention includes: a coal-fired power generation system including a boiler evaporator, the boiler evaporator having a preheating medium outlet and a preheating medium inlet; a molten salt heat storage and release system including a molten salt circulation loop and a preheating pipeline, the molten salt circulation loop including a heat storage device, a high-temperature molten salt tank, a heat exchanger, and a low-temperature molten salt tank connected in sequence, the molten salt circulation loop further provided with a molten salt pump for driving the molten salt to circulate, the preheating pipeline being connected between the preheating medium outlet and the preheating medium inlet, the preheating pipeline including a first preheating pipeline and a second preheating pipeline, in the flow direction of the preheating medium, the second preheating pipeline is connected to the downstream side of the first preheating pipeline, the first preheating pipeline is provided in the heat storage device and exchanges heat with the heat storage device, and the first preheating pipeline is provided in the heat exchanger and exchanges heat with the heat exchanger.

[0005] According to the start-up system of a coal-fired boiler based on molten salt heat storage according to an embodiment of the present invention, by enabling the preheating medium to exchange heat with the heat storage device in the heat storage device and also to exchange heat with the molten salt through a heat exchanger, a large amount of heat can be transferred to the steam-water working medium of the boiler in a short time, shortening the time required for "warming up the boiler"; the steam-water working medium heated by the molten salt can also enter the boiler evaporator through the preheating medium inlet to heat the boiler evaporator, accelerating the "warming up of the furnace" process, further improving the start-up speed, and significantly enhancing the start-up speed and efficiency of the coal-fired power generation unit; in addition, this technology does not rely on expensive fuel, has low costs and is economical, and does not require steam support from adjacent units, having flexibility.

[0006] According to some embodiments of the present invention, the first preheating pipeline is wound around the outer peripheral side of the heat storage device.

[0007] According to some embodiments of the present invention, the heat storage device includes a heat storage device inner container and heat conducting plate sheets. The heat conducting plate sheets are sleeved on the outer peripheral side of the heat storage device inner container and are thermally connected to the heat storage device inner container. The first preheating pipeline is wound around the outer peripheral side of the heat conducting plate sheets and is thermally connected to the heat conducting plate sheets.

[0008] According to some embodiments of the present invention, there are multiple heat exchangers. In the flowing direction of the molten salt, the multiple heat exchangers are arranged in sequence and are respectively a preheating heat exchanger, an evaporation heat exchanger, and a superheating heat exchanger in sequence. The second preheating pipeline includes a first preheating section, a second preheating section, and a third preheating section that are sequentially connected along the flowing direction of the preheating medium. The first preheating section is arranged in the preheating heat exchanger and exchanges heat with the preheating heat exchanger. The second preheating section is arranged in the evaporation heat exchanger and exchanges heat with the evaporation heat exchanger. The third preheating section is arranged in the superheating heat exchanger and exchanges heat with the superheating heat exchanger.

[0009] According to some embodiments of the present invention, the first preheating pipeline is connected to the preheating medium outlet through a first connecting pipeline. The first connecting pipeline is provided with a conveying valve and a reheater. The conveying valve is used to control the on-off of the first connecting pipeline. The reheater is connected to the downstream side of the conveying valve;

[0010] The second preheating pipeline is connected to the preheating medium inlet through a second connecting pipeline. The second connecting pipeline is provided with a first pressure reducing valve.

[0011] According to some embodiments of the present invention, it includes a makeup water pipe and a feed water pump. The makeup water pipe is connected to the first connecting pipeline and is used to supplement the preheating medium to the first connecting pipeline. The feed water pump is arranged on the makeup water pipe.

[0012] According to some embodiments of the present invention, the coal-fired power generation system further includes a cold air pretreatment device, which includes a fan, a filter box, an air compressor, and a second pressure reducing valve connected in series in sequence. The air compressor is used to convey the compressed air into the boiler evaporator. A wire fixing device is installed on the outer wall of the air compressor, and a plurality of wire routing channels are formed in the wire fixing device, and the wire routing channels are used for the wire harness routing of the air compressor.

[0013] According to some embodiments of the present invention, the wire fixing device includes a wire routing frame, and the wire routing frame includes a fixed connection block, a movable connection plate, a movable mounting plate, and an adjusting member. The fixed connection block and the movable mounting plate are connected along a first direction and jointly define a moving space. The movable connection plate is disposed in the moving space and jointly defines a plurality of the wire routing channels arranged at intervals along a second direction with the fixed connection block. The wire routing channels penetrate through the wire routing frame along a third direction. The third direction, the second direction, and the first direction are perpendicular to each other in pairs. An installation hole extending along the first direction is provided on the movable mounting plate, and the adjusting member passes through the installation hole and is threadedly connected to the installation hole. The free end of the adjusting member is rotatably connected to the movable connection plate, and the cross-sectional area of the wire routing channel is adjusted by rotating the adjusting member.

[0014] According to some embodiments of the present invention, a connection sleeve block is provided on one side of the movable connection plate facing the movable mounting plate, a rotation cavity is formed in the connection sleeve block, a rotating disk is provided at the free end of the adjusting member, and the rotating disk is located in the rotation cavity and is rotatable.

[0015] According to some embodiments of the present invention, the wire fixing device includes an installation frame, the installation frame is connected to one side of the wire routing frame along the third direction, a wire routing cavity is formed in the installation frame, both sides of the installation frame along the third direction are open, and connection support feet are provided on the installation frame, and the connection support feet are connected to the outer wall of the air compressor.

[0016] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be understood through the practice of the present invention. Description of the Drawings

[0017] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0018] Figure 1 is a schematic diagram of a coal-fired boiler startup system based on molten salt thermal energy storage according to some embodiments of the present invention;

[0019] Figure 2 isFigure 1 Schematic diagram of the cold air pretreatment device in

[0020] Figure 3 is Figure 1 Partial schematic diagram of the heat storage device in

[0021] Figure 4 is Figure 1 Schematic diagram of the wire fixing device in

[0022] Figure 5 is Figure 4 Schematic diagram of the wire routing frame in

[0023] Figure 6 is Figure 5 Assembly drawing of the movable mounting plate and the movable connecting plate in

[0024] Figure 7 is Figure 5 Assembly drawing of the movable connecting plate and the adjusting part in

[0025] Reference numerals:

[0026] 100, Coal-fired boiler startup system based on molten salt heat storage;

[0027] 10, Coal-fired power generation system; 11, Boiler evaporator; 111, Water wall; 112, Superheater; 113, Reheater; 114, Economizer; 12, Preheated medium outlet; 13, First connecting pipeline; 14, Delivery valve; 15, Re-preheater; 16, Preheated medium inlet; 17, Second connecting pipeline; 18, First pressure reducing valve; 19, Make-up water pipe; 20, Feed water pump; 21, Cold air pretreatment device; 22, Fan; 23, Filter box; 24, Air compressor; 25, Second pressure reducing valve;

[0028] 30, Wire fixing device; 31, Wire routing channel; 32, Wire routing frame; 33, Fixed connection block; 34, Movable connecting plate; 35, Moving space; 36, Connecting sleeve block; 37, Rotating cavity; 38, Movable mounting plate; 39, Mounting hole; 40, Adjusting part; 41, Rotating disk; 42, Mounting frame; 43, Connecting support leg;

[0029] 50, Molten salt heat storage and release system; 51, Molten salt circulation loop; 52, Preheating pipeline; 53, First preheating pipeline; 54, Second preheating pipeline; 55, First preheating section; 56, Second preheating section; 57, Third preheating section; 58, Heat storage device; 60, Heat conducting plate; 61, High-temperature molten salt tank; 62, Low-temperature molten salt tank; 63, Molten salt pump; 64, Heat exchanger; 65, Preheating heat exchanger; 66, Evaporation heat exchanger; 67, Superheating heat exchanger. Specific implementation mode

[0030] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention and should not be construed as limiting the present invention.

[0031] Reference is made below Figures 1-7 to describe a coal-fired boiler startup system 100 based on molten salt thermal energy storage according to an embodiment of the present invention.

[0032] The coal-fired boiler startup system 100 based on molten salt thermal energy storage according to an embodiment of the present invention includes: a coal-fired power generation system 10 and a molten salt heat storage and release system 50.

[0033] Referring to Figure 1 , the coal-fired power generation system 10 includes a boiler evaporator 11, and the boiler evaporator 11 has a preheated medium outlet 12 and a preheated medium inlet 16. For example, the preheated medium may be water. The preheated medium enters the boiler evaporator 11 through the preheated medium inlet 16, preheats the boiler evaporator 11, and then leaves the boiler evaporator 11 through the preheated medium outlet 12.

[0034] The molten salt heat storage and release system 50 includes a molten salt circulation loop 51 and a preheating pipeline 52. The molten salt circulation loop 51 includes a heat storage device 58, a high-temperature molten salt tank 61, a heat exchanger 64, and a low-temperature molten salt tank 62 connected in sequence. The molten salt circulation loop 51 is also provided with a molten salt pump 63 for driving the molten salt to circulate. The molten salt pump 63 can promote the flow of the molten salt in the molten salt circulation loop 51. For example, the molten salt pump 63 may include a high-temperature molten salt pump 63 and a low-temperature molten salt pump 63. The low-temperature molten salt is stored in the low-temperature molten salt tank 62 and flows into the heat storage device 58 under the driving action of the molten salt pump 63 to exchange heat with the heat storage device 58

[0035] The preheating pipeline 52 is connected between the preheating medium outlet 12 and the preheating medium inlet 16. The preheating pipeline 52 includes a first preheating pipeline 53 and a second preheating pipeline 54. In the flowing direction of the preheating medium, the second preheating pipeline 54 is connected to the downstream side of the first preheating pipeline 53. The first preheating pipeline 53 is disposed in the heat storage device 58 and exchanges heat with the heat storage device 58, and the second preheating pipeline 54 is disposed in the heat exchanger 64 and exchanges heat with the heat exchanger 64. By disposing the first preheating pipeline 53 in the heat storage device 58 and exchanging heat with the heat storage device 58, the heat storage device 58 can increase the temperature of the preheating medium in the first preheating pipeline 53. By disposing the second preheating pipeline 54 in the heat exchanger 64 and exchanging heat with the heat exchanger 64, the high-temperature molten salt in the heat exchanger 64 can exchange heat with the preheating medium in the second preheating pipeline 54, more fully increasing the temperature of the preheating medium in the second preheating pipeline 54, transferring the heat in the heat storage device 58 and the heat in the high-temperature molten salt to the preheating medium in a short time, quickly increasing the temperature of the preheating medium, and shortening the time required for pot warming; moreover, making this part of the preheating medium enter the boiler evaporator 11 through the preheating medium inlet 16 to heat the boiler evaporator 11, accelerating the pot warming process, enabling the boiler evaporator 11 to reach the temperature required for startup faster, increasing the startup speed, and improving the efficiency.

[0036] For the coal-fired boiler startup system 100 based on molten salt heat storage according to an embodiment of the present invention, by enabling the preheating medium to exchange heat with the heat storage device 58 in the heat storage device 58 and also enabling heat exchange with the molten salt through the heat exchanger 64, a large amount of heat can be transferred to the preheating medium of the boiler in a short time, shortening the time required for "pot warming"; the steam-water working medium heated by the molten salt can also enter the boiler evaporator 11 through the preheating medium inlet 16 to heat the boiler evaporator 11, accelerating the "furnace warming" process, further increasing the startup speed, and significantly improving the startup speed and efficiency of the coal-fired power generation unit; in addition, this technology does not rely on expensive fuel, has low costs, is economical, and does not require the steam support of adjacent units, having flexibility.

[0037] According to some embodiments of the present invention, referring to Figure 1 and Figure 3 , the first preheating pipeline 53 is wound around the outer peripheral side of the heat storage device 58. By winding the first preheating pipeline 53 around the outer peripheral side of the heat storage device 58, the first preheating pipeline 53 can be more convenient for heat exchange with the heat storage, increasing the temperature of the preheating medium in the first preheating pipeline 53, shortening the time required for pot warming, and improving the efficiency.

[0038] According to some embodiments of the present invention, referring to Figure 1 and Figure 3, the heat accumulator 58 includes an inner tank of the heat accumulator 58 and a heat conduction plate 60. The heat conduction plate 60 is sleeved on the outer peripheral side of the inner tank of the heat accumulator 58 and is thermally connected to the inner tank of the heat accumulator 58. The first preheating pipeline 53 is wound around the outer peripheral side of the heat conduction plate 60 and is thermally connected to the heat conduction plate 60. By sleeving the heat conduction plate 60 on the outer peripheral side of the inner tank of the heat accumulator 58, the heat conduction plate 60 can more easily exchange heat with external components; by thermally connecting the heat conduction plate 60 to the inner tank of the heat accumulator 58, the first preheating pipeline 53 is wound around the outer peripheral side of the heat conduction plate 60 and is thermally connected to the heat conduction plate 60, the heat conduction plate 60 can receive the heat stored in the inner tank of the heat accumulator 58 and transfer this part of the heat to the first preheating pipeline 53, more fully raising the temperature of the preheating medium in the first preheating pipeline 53, shortening the time required for the hot pot, and improving the efficiency.

[0039] For example, the heat accumulator 58 is connected to a coal-fired power generation unit and is used to store the waste heat generated during the power generation operation of the coal-fired power generation unit, and this part of the heat is utilized again when the coal-fired power generation unit needs to start preheating.

[0040] According to some embodiments of the present invention, referring to Figure 1 , there are multiple heat exchangers 64. In the flowing direction of the molten salt, the multiple heat exchangers 64 are arranged in sequence and are respectively a preheating heat exchanger 65, an evaporation heat exchanger 66, and a superheating heat exchanger 67 in sequence. The second preheating pipeline 54 includes a first preheating section 55, a second preheating section 56, and a third preheating section 57 that are connected in sequence along the flowing direction of the preheating medium. The first preheating section 55 is arranged in the preheating heat exchanger 65 and exchanges heat with the preheating heat exchanger 65. The second preheating section 56 is arranged in the evaporation heat exchanger 66 and exchanges heat with the evaporation heat exchanger 66. The third preheating section 57 is arranged in the superheating heat exchanger 67 and exchanges heat with the superheating heat exchanger 67. By having multiple heat exchangers 64 and being respectively a preheating heat exchanger 65, an evaporation heat exchanger 66, and a superheating heat exchanger 67 in sequence, the heat exchange medium in the second preheating pipeline 54 can be heated sequentially in the multiple heat exchangers 64, more fully raising the temperature of the heat exchange medium in the second heat exchange pipeline, shortening the time required for the hot pot, and improving the efficiency.

[0041] For example, the preheating heat exchanger 65 includes a first preheating inlet, a second preheating inlet, a first preheating outlet, and a second preheating outlet. The first preheating inlet and the first preheating outlet are connected through a molten salt preheating pipeline 52. The second preheating inlet and the second preheating outlet are connected through a water vapor preheating pipeline 52. The evaporation heat exchanger 66 includes a first evaporation inlet, a second evaporation inlet, a first evaporation outlet, and a second evaporation outlet. The first evaporation inlet and the first evaporation outlet are connected through a molten salt evaporation pipeline. The second evaporation inlet and the second evaporation outlet are connected through a water vapor evaporation pipeline. The superheating heat exchanger 67 includes a first superheating inlet, a second superheating inlet, a first superheating outlet, and a second superheating outlet. The first superheating inlet and the first superheating outlet are connected through a molten salt superheating pipeline. The second superheating inlet and the second superheating outlet are connected through a water vapor superheating pipeline;

[0042] The first superheating outlet and the first evaporation inlet are connected through a fourth molten salt pipeline. The first evaporation outlet and the first preheating inlet are connected through a fifth molten salt pipeline. The second preheating outlet and the second evaporation inlet are connected through a second water vapor pipeline. The second evaporation outlet and the second superheating inlet are connected through a third water vapor pipeline. The first water vapor pipeline is connected to the second preheating inlet. The water vapor output pipeline is connected to the second superheating outlet.

[0043] By making the second preheating pipeline 54 include a first preheating section 55, a second preheating section 56, and a third preheating section 57 connected in sequence along the flow direction of the preheating medium, and the first preheating section 55 is arranged in the preheating heat exchanger 65 and exchanges heat with the preheating heat exchanger 65, the temperature of the heat exchange medium in the first preheating section 55 can be made lower, and it exchanges heat with the molten salt in the preheating heat exchanger 65 at a lower temperature; by making the second preheating section 56 arranged in the evaporation heat exchanger 66 and exchanging heat with the evaporation heat exchanger 66, the temperature of the heat exchange medium in the second preheating section 56 can be made medium, and it exchanges heat with the molten salt in the evaporation heat exchanger 66 at a medium temperature; by making the third preheating section 57 arranged in the superheating heat exchanger 67 and exchanging heat with the superheating heat exchanger 67, the temperature of the heat exchange medium in the third preheating section can be made the highest, and it exchanges heat with the molten salt in the superheating heat exchanger 67 at the highest temperature, realizing the step-by-step heat exchange of the heat exchange medium in the second preheating pipeline 54, more fully increasing the temperature of the heat medium in the second heat exchange pipeline, shortening the time required for the warm pot, and improving the efficiency.

[0044] According to some embodiments of the present invention, with reference to Figure 1, the first preheating pipeline 53 is connected to the preheating medium outlet 12 through the first connecting pipeline 13. The first connecting pipeline 13 is provided with a conveying valve 14 and a reheater 15. The conveying valve 14 is used to control the on-off of the first connecting pipeline 13, and the reheater 15 is connected to the downstream side of the conveying valve 14. By connecting the first preheating pipeline 53 to the preheating medium outlet 12 through the first connecting pipeline 13, the heat exchange medium remaining after heating the boiler evaporator 11 can be recycled, avoiding waste of the heat exchange medium. By providing the reheater 15 in the first connecting pipeline 13, the heat exchange medium with a reduced temperature after heat exchange can be reheated and its temperature increased through the reheater 15, raising the temperature of the heat exchange medium in the first connecting pipeline 13, and thus raising the temperature of the heat exchange medium in the first preheating pipeline 53. By providing the conveying valve 14 in the first connecting pipeline 13, the first connecting pipeline 13 can be connected or disconnected as needed; by connecting the reheater 15 to the downstream side of the conveying valve 14, the conveying valve 14 can also have the function of opening or closing the inflow of the heat exchange medium into the reheater 15. Under the condition that the reheater 15 is not required to raise the temperature of the heat exchange medium, the conveying valve 14 can be closed to avoid wasting energy.

[0045] The second preheating pipeline 54 is connected to the preheating medium inlet 16 through the second connecting pipeline 17. The second connecting pipeline 17 is provided with a first pressure reducing valve 18. By connecting the second preheating pipeline 54 to the preheating medium inlet 16 through the second connecting pipeline 17, the second connecting pipeline 17 connects the preheating medium in the second preheating pipeline 54 to the preheating medium inlet 16, enabling the preheating medium to heat the boiler evaporator 11.

[0046] According to some embodiments of the present invention, referring to Figure 1 , the coal-fired boiler startup system includes a makeup water pipe 19 and a feed water pump 20. The makeup water pipe 19 is connected to the first connecting pipeline 13 and is used to supplement the preheating medium to the first connecting pipeline 13. The feed water pump 20 is provided on the makeup water pipe 19. By including the makeup water pipe 19 and the feed water pump 20 in the coal-fired boiler startup system, the makeup water pump can supplement the preheating medium to the first connecting pipeline 13, and can supplement the heat exchange medium when the flow rate of the heat exchange medium in the first connecting pipeline 13 is insufficient; by including the feed water pump 20 in the coal-fired boiler startup system, the makeup water pipe 19 can be connected or disconnected according to the flow rate of the heat exchange medium in the first connecting pipeline 13, avoiding excessive makeup water or too little heat exchange medium in the first connecting pipeline 13.

[0047] According to some embodiments of the present invention, referring to Figure 1 and Figure 2, the coal-fired power generation system 10 further includes a cold air pretreatment device 21. The cold air pretreatment device 21 includes a fan 22, a filter box 23, an air compressor 24, and a second pressure reducing valve 25 that are connected in series in sequence. The air compressor 24 is used to transport the compressed air into the boiler evaporator 11. A wire fixing device 30 is installed on the outer wall of the air compressor 24. Multiple wire routing channels 31 are formed in the wire fixing device 30, and the wire routing channels 31 are used for the wire harness routing of the air compressor 24. By making the coal-fired power generation system 10 further include the cold air pretreatment device 21, the air can be compressed and heated and then introduced into the boiler evaporator 11, so as to more fully increase the temperature of the boiler evaporator 11 and accelerate the speed of the preheating process. By making the cold air pretreatment device 21 include the filter box 23, the filter box 23 can filter the air entering the cold air pretreatment device 21 to prevent impurities in the air from entering the coal-fired power generation system 10. For example, the filter box 23 includes a primary filter screen and two fine filter screens, and the primary filter screen and the fine filter screens are arranged at intervals along the air flow direction and filter the air.

[0048] By installing the wire fixing device 30 on the outer wall of the air compressor 24 and routing the wire harness of the air compressor 24 along the wire routing channels 31, the wire harness of the air compressor 24 can be prevented from being wound or interfering with other components.

[0049] For example, the startup method of the coal-fired power generation system 10 according to an embodiment of the present invention includes:

[0050] The molten salt is transferred from the high-temperature molten salt tank 61 to the low-temperature molten salt tank 62, and the molten salt sequentially flows through the superheater 112, the evaporator, and the preheater and releases heat;

[0051] When the condensed water flowing into the first connection pipeline 13 from the reheater 15 is insufficient, the feed water pump 20 can be started to supplement the preheating medium. Water enters the first connection pipeline 13 through the make-up water pipe 19 and enters the first preheating pipeline 53. It flows into the heat storage device 58 through the first preheating pipeline 53 and is heated, then enters the second preheating pipeline 54 and is preheated by the preheater to form saturated water. The formed saturated water forms saturated steam in the evaporator, and finally enters the superheater 112 to form superheated steam. The formed superheated steam sequentially enters the water wall 111, the superheater 112, the reheater 113, and the economizer 114 through the superheated steam delivery pipe to heat the metal pipeline, and finally is transported to the reheater 15 through the steam delivery pipe;

[0052] During the process of the superheated steam heating the metal pipeline, it will slowly condense into condensed water. The condensed water is preheated by the reheater 15 to form warm water with a temperature and then returns to the molten salt-steam preheater through the superheated steam delivery pipe by opening the feed water bypass valve, forming a cyclic use of water;

[0053] Start the fan 22 to send the outside cold air into the interior of the filter box 23. The primary filter screen and the fine filter screen arranged inside the filter box 23 are used to filter the dust and impurities in the air to prevent pipeline blockage. After filtration, the air enters the air compressor 24 for compression. The air can be preliminarily heated. After heating, it is depressurized through the compressor pressure relief valve and then enters the water wall 111, superheater 112, reheater 113, and economizer 114 in sequence for multiple heating, and then is discharged into the furnace interior.

[0054] When the temperature inside the boiler furnace reaches the standard, the boiler can be started to start the coal-fired power generation system 10.

[0055] According to some embodiments of the present invention, referring to Figures 4-7 , the wire fixing device 30 includes a wire routing frame 32. The wire routing frame 32 includes a fixed connection block 33, a movable connection plate 34, a movable mounting plate 38, and an adjusting member 40. The fixed connection block 33 and the movable mounting plate 38 are connected along a first direction (such as the e1 direction in the attached drawing) and jointly define a moving space 35. The movable connection plate 34 is disposed in the moving space 35. The movable connection plate 34 and the fixed connection block 33 jointly define a plurality of wire routing channels 31 arranged at intervals along a second direction (such as the e2 direction in the attached drawing). The wire routing channels 31 penetrate the wire routing frame 32 along a third direction (such as the e3 direction in the attached drawing). The third direction, the second direction, and the first direction are perpendicular to each other pairwise. The movable mounting plate 38 is provided with a mounting hole 39 extending along the first direction. The adjusting member 40 passes through the mounting hole 39 and is threadedly connected to the mounting hole 39. The free end of the adjusting member 40 is rotatably connected to the movable connection plate 34. By rotating the adjusting member 40, the cross-sectional area of the wire routing channel 31 can be adjusted. By disposing the movable connection plate 34 in the moving space 35, the movable connection plate 34 can move along the second direction; by rotatably connecting the free end of the adjusting member 40 to the movable connection plate 34, relevant personnel can rotate the adjusting member 40 to change the position of the movable connection plate 34 in the second direction, thereby adjusting the cross-sectional area of the wire routing channel 31, which is convenient for fixing the wire harness and can also fully restrain wire harnesses of different thicknesses.

[0056] For example, a plurality of connection protrusions are provided on the movable connection plate 34, and a plurality of connection grooves are provided on the fixed connection block 33. When the movable connection plate 34 is matched with the fixed connection block 33, the plurality of connection protrusions are respectively received in the corresponding connection grooves.

[0057] For example, a hook is provided on the fixed connection block 33, and a buckle is provided on the movable mounting plate. The hook and the buckle are connected in a matching manner.

[0058] According to some embodiments of the present invention, referring to Figures 4-7, on one side of the movable connecting plate 34 facing the movable mounting plate 38, there is a connecting sleeve block 36. A rotating cavity 37 is formed inside the connecting sleeve block 36. The free end of the adjusting member 40 is provided with a rotating disk 41. The rotating disk 41 is located inside the rotating cavity 37 and can rotate. By making the rotating disk 41 located inside the rotating cavity 37 and capable of rotating, the adjusting member 40 can rotate relative to the movable connecting plate 34. Moreover, the rotating cavity 37 can limit the rotating disk 41, enabling the movable connecting plate 34 to move linearly along the second direction following the adjusting member 40. When the relevant personnel rotate the adjusting member 40, the adjusting member 40 rotates and moves along the second direction. Since the adjusting member 40 can rotate relative to the movable connecting plate 34, the movable connecting plate 34 can only move linearly along the second direction following the adjusting member 40 and does not follow the adjusting member 40 to rotate, so as to achieve the effect of changing the cross-sectional area of the wire routing channel 31.

[0059] According to some embodiments of the present invention, referring to Figures 4-7 , the wire fixing device 30 includes a mounting frame 42. The mounting frame 42 is connected to one side of the wire routing frame 32 along the third direction. A wire routing cavity is formed inside the mounting frame 42. Both sides of the mounting frame 42 along the third direction are open. Connecting support feet 43 are provided on the mounting frame 42. The connecting support feet 43 are connected to the outer wall of the air compressor 24. By making both sides of the mounting frame 42 along the third direction open, the wire harness can pass through the mounting frame 42 from the third direction, facilitating wire routing. By making the connecting support feet 43 provided on the mounting frame 42 and the connecting support feet 43 connected to the outer wall of the air compressor 24, the whole wire fixing device 30 can be fixed on the outer wall of the air compressor 24, facilitating the arrangement and routing of the wire harness of the air compressor 24.

[0060] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation to the present invention.

[0061] In the description of the present invention, the "first feature" and "second feature" may include one or more of such features.

[0062] In the description of the present invention, the meaning of "a plurality of" is two or more.

[0063] In the description of the present invention, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but are in contact through additional features therebetween.

[0064] In the description of the present invention, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than that of the second feature.

[0065] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0066] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A coal-fired boiler startup system based on molten salt heat storage, characterized in that: include: A coal-fired power generation system includes a boiler evaporator having a preheating medium outlet and a preheating medium inlet; A molten salt heat storage and release system comprises a molten salt circulation loop and a preheating pipeline, wherein the molten salt circulation loop comprises a heat storage device, a high-temperature molten salt tank, a heat exchanger and a low-temperature molten salt tank connected in sequence, and the molten salt circulation loop is also provided with a molten salt pump for driving the circulation of the molten salt, the preheating pipeline is connected between the preheating medium outlet and the preheating medium inlet, the preheating pipeline comprises a first preheating pipeline and a second preheating pipeline, in the flow direction of the preheating medium, the second preheating pipeline is connected to the downstream side of the first preheating pipeline, the first preheating pipeline is arranged in the heat storage device and exchanges heat with the heat storage device, and the first preheating pipeline is arranged in the heat exchanger and exchanges heat with the heat exchanger.

2. The coal-fired boiler startup system based on molten salt heat storage according to claim 1 is characterized in that: The first preheating pipeline is arranged around the outer peripheral side of the heat storage device.

3. The coal-fired boiler startup system based on molten salt heat storage according to claim 2 is characterized in that: The heat reservoir comprises a heat reservoir inner tank and a heat conductive plate, wherein the heat conductive plate is sleeved on the outer peripheral side of the heat reservoir inner tank and is heat conductively connected to the heat reservoir inner tank, and the first preheating pipeline is arranged around the outer peripheral side of the heat conductive plate and is heat conductively connected to the heat conductive plate.

4. The coal-fired boiler startup system based on molten salt heat storage according to claim 1 is characterized in that: There are multiple heat exchangers, and in the flow direction of the molten salt, the multiple heat exchangers are arranged in sequence and are respectively a preheating heat exchanger, an evaporating heat exchanger and a superheating heat exchanger. The second preheating pipeline includes a first preheating section, a second preheating section and a third preheating section which are connected in sequence along the flow direction of the preheating medium. The first preheating section is arranged in the preheating heat exchanger and exchanges heat with the preheating heat exchanger, the second preheating section is arranged in the evaporating heat exchanger and exchanges heat with the evaporating heat exchanger, and the third preheating section is arranged in the superheating heat exchanger and exchanges heat with the superheating heat exchanger.

5. The coal-fired boiler startup system based on molten salt heat storage according to claim 1 is characterized in that: The first preheating pipeline is connected to the preheating medium outlet through a first connecting pipeline, the first connecting pipeline is provided with a delivery valve and a re-preheater, the delivery valve is used to control the on-off of the first connecting pipeline, and the re-preheater is connected to the downstream side of the delivery valve; The second preheating pipeline is connected to the preheating medium inlet through a second connecting pipeline, and the second connecting pipeline is provided with a first pressure reducing valve.

6. The coal-fired boiler startup system based on molten salt heat storage according to claim 5 is characterized in that: It includes a water supply pipe and a water supply pump. The water supply pipe is connected to the first connecting pipeline and is used to supplement the preheating medium to the first connecting pipeline. The water supply pump is arranged on the water supply pipe.

7. The coal-fired boiler startup system based on molten salt heat storage according to any one of claims 1 to 6, characterized in that: The coal-fired power generation system also includes a cold air pretreatment device, which includes a fan, a filter box, an air compressor and a second pressure reducing valve connected in series in sequence. The air compressor is used to transport compressed air to the boiler evaporator. A wiring fixing device is installed on the outer wall of the air compressor, and a plurality of wiring channels are formed in the wiring fixing device. The wiring channels are used for wiring the wiring harness of the air compressor.

8. The coal-fired boiler startup system based on molten salt heat storage according to claim 7 is characterized in that: The wiring fixing device includes a wiring frame, and the wiring frame includes a fixed connection block, a movable connection plate, a movable mounting plate and an adjusting member. The fixed connection block is connected to the movable mounting plate along a first direction and jointly defines a moving space. The movable connection plate is arranged in the moving space and jointly defines a plurality of wiring channels arranged at intervals along a second direction with the fixed connection block. The wiring channels penetrate the wiring frame along a third direction. The third direction, the second direction and the first direction are perpendicular to each other. A mounting hole extending along the first direction is provided on the movable mounting plate. The adjusting member is penetrated through the mounting hole and threadedly connected to the mounting hole. The free end of the adjusting member is rotatably connected to the movable connection plate. The cross-sectional area of ​​the wiring channel is adjusted by rotating the adjusting member.

9. The coal-fired boiler startup system based on molten salt heat storage according to claim 8 is characterized in that: A connecting sleeve block is provided on one side of the movable connecting plate facing the movable mounting plate, a rotating cavity is formed in the connecting sleeve block, and a rotating disk is provided at the free end of the adjusting member, and the rotating disk is located in the rotating cavity and is rotatable.

10. The coal-fired boiler startup system based on molten salt heat storage according to claim 8, characterized in that: The wire fixing device includes a mounting frame, the mounting frame is connected to one side of the wiring frame along the third direction, a wiring cavity is formed in the mounting frame, both sides of the mounting frame along the third direction are open, and the mounting frame is provided with connecting legs, and the connecting legs are connected to the outer wall of the air compressor.

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