Coal mill inlet air mixing and equalizing device and boiler deep peak regulation combustion adjustment system

Abstract

The present invention provides a coal mill air inlet mixing and equalizing flow device and a boiler deep peak shaving combustion adjustment system, which relate to the field of thermal power generation technology. The coal mill air inlet mixing and equalizing flow device includes: an equalizing heat conduction box, a plurality of hot primary air ducts and a plurality of cold primary air ducts arranged in layers and staggered, the hot primary air enters the corresponding hot primary air duct through the hot air inlet and flows out from the corresponding hot air outlet, the cold primary air enters the corresponding cold primary air duct through the cold air inlet and flows out from the corresponding cold air outlet; an air equalizing pipe, one end of which is connected to the hot air outlet of the hot primary air duct and the cold air outlet of the cold primary air duct, and the other end is connected to the powder outlet of the coal mill; a plurality of guide plates are arranged at the cold air outlet of each cold primary air duct, and the flow direction of the cold primary air flowing out of the cold air outlet is controlled by the plurality of guide plates. The coal mill air inlet mixing and equalizing flow device and the boiler deep peak shaving combustion adjustment system solve the problem of poor flow field uniformity after the hot primary air and the cold primary air are mixed in the prior art.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal power generation, and in particular to a coal mill air inlet mixing and equalizing flow device and a boiler deep peak regulation combustion adjustment system. Background Art

[0002] my country's energy production and consumption structures are trending toward clean energy. Increasing electricity consumption will primarily rely on new and renewable energy sources. Coal-fired power units will gradually shift from a power-based source to a regulating source. Further leveraging the flexible operation capabilities of coal-fired power units in the electricity market is imperative. When boilers participate in deep peak-shaving operations, their ability to maintain stable combustion at low loads is the most significant constraint on their flexible operation. Effective measures are urgently needed to improve these capabilities and enhance the safety and reliability of these units during deep peak-shaving operations.

[0003] The main factors that affect the stable combustion capacity of the boiler are: unit load, coal quality conditions, temperature of the primary air-powder mixture, coal powder fineness, air distribution method, output of each burner and air-powder uniformity, etc. During deep peak regulation, the unit load, coal quality conditions, air distribution method and output of each burner are relatively fixed and are difficult to control factors. Only the temperature of the primary air-powder mixture, coal powder fineness and air-powder uniformity can be adjusted to a certain extent. Before adjusting the temperature of the air-powder mixture, it is necessary to adjust the temperature of the air to the optimal temperature, and then mix the air and powder. In the existing technology, when adjusting the temperature of the air, the hot primary air and the cold primary air are mixed to adjust the temperature of the air. However, the uniformity of the flow field after the hot primary air and the cold primary air are mixed is poor, which affects the subsequent boiler combustion. Therefore, there is an urgent need for a device that can optimize the uniformity of the flow field after the hot primary air and the cold primary air are mixed. Summary of the Invention

[0004] The purpose of the embodiments of the present invention is to provide a coal mill inlet air mixing and equalizing device and a boiler deep peak-shaving combustion adjustment system to solve the problem of poor flow field uniformity after mixing hot primary air and cold primary air in the prior art.

[0005] In order to achieve the above object, the present invention provides a coal mill inlet air mixing and equalizing device for mixing hot primary air and cold primary air and then delivering them to the coal mill outlet. The coal mill inlet air mixing and equalizing device comprises:

[0006] The heat conduction box has multiple hot primary air ducts and cold primary air ducts, which are layered, staggered and parallel to each other. The hot primary air enters the corresponding hot primary air duct through the hot air inlet and flows out from the corresponding hot air outlet. The cold primary air enters the corresponding cold primary air duct through the cold air inlet and flows out from the corresponding cold air outlet.

[0007] An air equalizing pipe, one end of which is connected to the hot air outlet of each hot primary air duct and the cold air outlet of each cold primary air duct, and the other end of which is connected to the powder outlet of the coal mill;

[0008] A plurality of guide plates are arranged at the cold air outlet of each cold primary air duct, and the flow direction of the cold primary air flowing out of the cold air outlet is controlled by the plurality of guide plates.

[0009] Specifically, the flow-sharing heat conduction box includes: multiple outer box plates and multiple partitions; multiple outer box plates are enclosed to form the flow-sharing heat conduction box; multiple partitions are arranged parallel to each other in the flow-sharing heat conduction box, dividing the flow-sharing heat conduction box into multiple hot primary air ducts and multiple cold primary air ducts, and the hot air inlet and hot air outlet of the hot primary air duct and the cold air inlet and cold air outlet of the cold primary air duct are opened on the corresponding outer box plates.

[0010] Specifically, the hot air inlet of the hot primary air duct and the cold air inlet of the cold primary air duct are respectively opened on two adjacent outer box plates, and the hot air outlet of the hot primary air duct and the cold air outlet of the cold primary air duct are opened on the same outer box plate.

[0011] Specifically, the cold air inlet and the cold air outlet of each cold primary air duct are respectively opened on two adjacent outer box panels.

[0012] Specifically, each guide plate is an arc-shaped plate.

[0013] Specifically, the coal mill inlet air mixing and flow balancing device further includes:

[0014] A hot air source delivers hot primary air to each hot primary air duct of the flow-balanced heat transfer box through a hot primary air duct;

[0015] The cold air source delivers cold primary air to each cold primary air duct of the flow-sharing heat transfer box through the cold primary air duct.

[0016] On the other hand, the present invention provides a boiler deep peak-shaving combustion adjustment system, including a boiler, a coal mill, a coal feeder and a coal drop pipe. The boiler deep peak-shaving combustion adjustment system also includes: the coal mill inlet air mixing and equalizing flow device described in any of the above items.

[0017] Specifically, the boiler deep peak-shaving combustion adjustment system further includes: a wind speed detection device provided on the gas equalizing pipe, for detecting the wind speed of the mixed gas of hot primary air and cold primary air flowing through the gas equalizing pipe.

[0018] Specifically, the wind speed detection device includes: a backrest tube, a protective sleeve and a driving mechanism;

[0019] The protective sleeve is in the shape of a cylinder with one end open, the backrest tube is arranged in the protective sleeve, and the backrest tube is used to detect wind speed;

[0020] A detection hole is opened on the wall of the gas equalizing pipe, and the open end of the protective sleeve extends into the gas equalizing pipe through the detection hole, and the protective sleeve can move along the extension direction of the detection hole;

[0021] The driving mechanism is used to drive the protective sleeve to move along the extending direction of the detection hole.

[0022] Specifically, the wind speed detection device further includes: a back-blowing mechanism;

[0023] A back-blowing air hole is provided at one end of the air equalizing pipe exposed outside the detection hole, and the back-blowing mechanism blows air into the protective sleeve through the back-blowing air hole to purge the backrest pipe arranged in the protective sleeve.

[0024] The coal mill inlet air mixing and equalizing device provided by the present invention is provided with an equalizing heat conduction box, and hot primary air ducts and cold primary air ducts are arranged in layers and staggered in the equalizing heat conduction box. Multiple guide plates are arranged at the cold air outlet of each layer of cold primary air duct. The flow direction of the cold primary air flowing out of the cold air outlet is adjusted by the multiple guide plates. When the hot primary air and cold primary air flow through the corresponding hot primary air duct and cold primary air duct respectively, heat exchange occurs with the hot primary air or cold primary air flowing in the adjacent hot primary air duct or cold primary air duct, so that the temperature difference between the hot primary air and the cold primary air is reduced. In this way, the temperature of the hot primary air when flowing out of the hot air outlet and the temperature of the cold primary air when flowing out of the cold air outlet are similar. After the two enter the equalizing pipe and mix, the flow field distribution of the hot and cold primary air formed is more uniform and stable. The present invention also provides a boiler deep peak-shaving combustion adjustment system. The coal mill air inlet mixing and equalizing device and boiler deep peak-shaving combustion adjustment system provided by the present invention not only solve the problem of poor flow field uniformity after mixing of hot primary air and cold primary air in the prior art, but also improve the combustion performance of subsequent boilers.

[0025] Other features and advantages of the embodiments of the present invention will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following detailed description, they are used to explain the embodiments of the present invention, but do not constitute a limitation of the embodiments of the present invention. In the accompanying drawings:

[0027] Figure 1 This is a structural schematic diagram of the flow-sharing heat conduction box in the coal mill air inlet mixing and flow-sharing device provided by the present invention;

[0028] Figure 2 yes Figure 1 Schematic diagram of the structure of the flow-sharing heat transfer box in the coal mill air mixing and flow-sharing device from different angles;

[0029] Figure 3 yes Figure 1 A cross-sectional view of a flow-sharing heat transfer box in a coal mill inlet air mixing and flow-sharing device in the extension direction of the hot primary air duct;

[0030] Figure 4 This is a schematic diagram of the arrangement of guide plates in the coal mill air inlet mixing and equalizing flow device provided by the present invention;

[0031] Figure 5 This is a schematic diagram of the layout of the boiler deep peak-shaving combustion adjustment system provided by the present invention;

[0032] Figure 6 It is a structural schematic diagram of the wind speed detection device in the boiler deep peak-shaving combustion adjustment system provided by the present invention.

[0033] Description of Reference Numerals

[0034] 1-hot primary air duct; 2-cold primary air duct; 3-flow-equalizing heat conduction box; 4-guide plate; 5-boiler; 6-wind speed detection device; 7-pulverizer; 8-coal feeder; 9-coal drop pipe; 31-hot primary air duct; 32-cold primary air duct; 34-outer box plate; 35-partition; 61-backrest pipe; 62-protective sleeve; 63-drive mechanism; 64-backblowing mechanism; A-gas equalizing pipe; 110-first regulating valve; 210-second regulating valve; 10-coal powder air flow distribution device; 11, 12, 13, 14-combustion regulating valve; 15, 16, 17, 18-wind speed measuring device; 19, 20, 21, 22-burner; 23-signal processing unit; 24-signal conversion module. DETAILED DESCRIPTION

[0035] The following describes the specific implementation of the embodiment of the present invention in detail with reference to the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the embodiment of the present invention and is not used to limit the embodiment of the present invention.

[0036] Figure 1 This is a schematic diagram of the structure of the flow-sharing heat transfer box in the coal mill air inlet mixing and flow-sharing device; Figure 2 yes Figure 1 Schematic diagram of the structure of the flow-sharing heat transfer box in the coal mill air mixing and flow-sharing device from different angles; Figure 3 yes Figure 1 A cross-sectional view of a flow-sharing heat transfer box in a coal mill inlet air mixing and flow-sharing device in the extension direction of the hot primary air duct; Figure 4 This is a schematic diagram of the arrangement of guide plates in the coal mill inlet air mixing and equalizing device; Figure 5 This is a schematic diagram of the layout of the boiler's deep peak-shaving combustion adjustment system; Figure 6 This is a schematic diagram of the structure of the wind speed detection device in the boiler deep peak regulation combustion adjustment system. Figures 1-6As shown, the present invention provides a coal mill inlet air mixing and equalizing device for mixing hot primary air and cold primary air and then delivering them to the powder outlet of the coal mill 7. The coal mill inlet air mixing and equalizing device includes:

[0037] The uniform flow heat conduction box 3 has a plurality of hot primary air ducts 31 and cold primary air ducts 32. The plurality of hot primary air ducts 31 and the plurality of cold primary air ducts 32 are arranged in layers, staggered and parallel to each other. The hot primary air enters the corresponding hot primary air duct 31 through the hot air inlet and flows out from the corresponding hot air outlet. The cold primary air enters the corresponding cold primary air duct 32 through the cold air inlet and flows out from the corresponding cold air outlet.

[0038] An air equalizing pipe A, one end of which is connected to the hot air outlet of each hot primary air duct 31 and the cold air outlet of each cold primary air duct 32, and the other end of which is connected to the powder outlet of the coal mill 7;

[0039] A plurality of guide plates 4 are arranged at the cold air outlet of each cold primary air duct 32 , and the flow direction of the cold primary air flowing out of the cold air outlet is controlled by the plurality of guide plates 4 .

[0040] The coal mill air inlet mixing and equalizing device provided by the present invention is as follows: Figure 1-Figure 3 As shown, a hot primary air duct 31 and a cold primary air duct 32 are layered in the uniform flow heat conduction box 3. The hot primary air enters the hot primary air duct 31 from the hot air inlet of the hot primary air duct 31 and flows out from the hot air outlet. The cold primary air enters the cold primary air duct 32 from the cold air inlet of the cold primary air duct 32 and flows out from the cold air outlet. When the hot primary air flows through the hot primary air duct 31, heat exchange occurs with the cold primary air flowing in the cold primary air duct 32 adjacent to the hot primary air duct 31. In this way, when the cold primary air and the hot primary air exchange heat in the uniform flow heat conduction box 3 The change makes the temperature difference between the cold primary air and the hot primary air gradually decrease, and the temperature of the hot primary air when flowing out from the hot air outlet is close to the temperature of the cold primary air flowing out from the cold air outlet in the adjacent cold primary air duct 32. When the hot primary air and the cold primary air enter the air equalizing pipe A, since the temperatures of the two are similar, the flow fields of the hot primary air and the cold primary air are stable when they are mixed in the air equalizing pipe A, and the temperature distribution of the formed hot and cold primary air is more uniform, which solves the problem of poor flow field uniformity after the hot primary air and the cold primary air are mixed in the prior art.

[0041] In one embodiment, Figure 1As shown, specifically, the flow-sharing heat transfer box 3 includes: multiple outer box panels 34 and multiple partitions 35; the multiple outer box panels 34 enclose the flow-sharing heat transfer box 3, and the multiple partitions 35 are arranged parallel to each other within the flow-sharing heat transfer box 3, dividing the flow-sharing heat transfer box 3 into multiple hot primary air ducts 31 and multiple cold primary air ducts 32. The hot air inlet and hot air outlet of the hot primary air ducts 31, as well as the cold air inlet and cold air outlet of the cold primary air ducts 32, are located on corresponding outer box panels 34. The hot air inlet of the hot primary air duct 31 and the cold air inlet of the cold primary air duct 32 are respectively located on two adjacent outer box panels 34, and the hot air outlet of the hot primary air duct 31 and the cold air outlet of the cold primary air duct 32 are respectively located on two adjacent outer box panels 34. The cold air inlet and cold air outlet of each cold primary air duct 32 are respectively located on two adjacent outer box panels 34. Each guide plate 4 is a curved plate.

[0042] like Figure 1-Figure 2 As shown, the flow-sharing heat conduction box 3 is a rectangular box body, which is assembled from a plurality of outer box plates 34. A plurality of partitions 35 are arranged in layers in the flow-sharing heat conduction box 3, and the interior of the flow-sharing heat conduction box 3 is divided into a plurality of hot primary air ducts 31 and cold primary air ducts 32 by the plurality of partitions 35. In order to enable the hot primary air and the cold primary air to exchange heat better, the hot air inlet of the hot primary air duct 31 and the cold air inlet of the cold primary air duct 32 are respectively arranged on two adjacent outer box plates 34 of the flow-sharing heat conduction box 3, and the hot air outlet and the hot air inlet are arranged in a straight line. In order to enable the hot primary air and the cold primary air to exchange heat better when flowing through the hot primary air duct 31 and the cold primary air duct 32, the cold air outlet and the cold air inlet of the cold primary air duct 32 are respectively arranged on two adjacent outer box plates 34, so that the cold air inlet and the cold air outlet are arranged on two outer box plates 34 perpendicular to each other. Figure 4 As shown, a guide plate 4 is provided at the cold air outlet of the cold primary air duct 32, and the guide plate 4 is used to change the flow direction of the cold primary air entering from the cold air inlet and flowing out from the cold air outlet. The guide effect of the guide plate 4 makes the flow direction of the cold primary air consistent with the flow direction of the hot primary air, ensuring that the flow field of the cold and hot primary air formed after mixing is stable. The guide plate 4 provided at the cold air outlet is arc-shaped, and the length of the guide plate 4 is different. Multiple guide plates 4 are arranged on the partition 35 from the side close to the cold air inlet to the side away from the cold air inlet according to the length of the guide plate 4. In this way, not only can the flow direction of the cold primary air be adjusted by the guide plate 4, but also the flow time of the cold primary air in the cold primary air duct 32 is extended by the guide plate 4, ensuring that the cold primary air can have a longer time to exchange heat with the hot primary air.

[0043] In order to supply air to the hot primary air duct 31 and the cold primary air duct 32 in the flow-balanced heat transfer box 3, specifically, the coal mill air inlet mixing and flow-balanced device further includes:

[0044] The hot air source delivers hot primary air to each hot primary air duct 31 of the flow-balanced heat transfer box 3 through the hot primary air duct 1;

[0045] The cold air source delivers cold primary air to each cold primary air duct 32 of the flow-balanced heat transfer box 3 through the cold primary air duct 2 .

[0046] Hot primary air is transported to each hot primary air duct 31 through the hot primary air duct 1, and cold primary air is transported to each cold primary air duct 32 through the cold primary air duct 2. In order to adjust the air volume of the hot primary air sent into the hot primary air duct 31 and the air volume of the cold primary air sent into the cold primary air duct 32, a first regulating valve 110 is provided on the hot primary air duct 1, and a second regulating valve 210 is provided on the cold primary air duct 2. The wind speed of the hot primary air flowing through the hot primary air duct 1 is adjusted by the first regulating valve 110, and the wind speed of the cold primary air flowing through the cold primary air duct 2 is adjusted by the second regulating valve 210. By adjusting the wind speed of the hot primary air and the wind speed of the cold primary air, the air volume is controlled.

[0047] On the other hand, the present invention provides a boiler deep peak-shaving combustion adjustment system, including a boiler 5, a coal mill 7, a coal feeder 8 and a coal drop pipe 9. The boiler deep peak-shaving combustion adjustment system also includes: the coal mill inlet air mixing and equalizing flow device described in any of the above items.

[0048] In one embodiment, Figure 5 As shown, a boiler 5 is provided. After being mixed and equalized by the coal mill inlet air mixing and equalizing device, the cold and hot primary air enter the pulverized coal outlet of the coal mill 7 so that the pulverized coal output from the pulverized coal outlet is brought into the boiler 5 through the cold and hot primary air for combustion. The coal feeder 8 delivers different types or qualities of coal into the coal mill 7 through the coal drop pipe 9. The coal entering the coal mill 7 is ground into pulverized coal. The cold and hot primary air carries the pulverized coal into the pulverized coal airflow distribution device 10, as shown. Figure 5 As shown, the boiler 5 is a square tangential boiler with four burners 19, 20, 21 and 22 on the same plane. The four burners 19, 20, 21 and 22 are connected to the pulverized coal air flow distribution device 10 through pipelines. A combustion regulating valve 11, 12, 13 and 14 is correspondingly provided on each pipeline between the four burners 19, 20, 21 and 22 and the pulverized coal air flow distribution device 10. The combustion regulating valves 11, 12, 13 and 14 regulate the hot and cold air entering the corresponding burners 19, 20, 21 and 22. The air volume of the primary air and pulverized coal mixture, in order to facilitate the staff to understand the combustion conditions of the four burners of boiler 5 and ensure the leveling of the burner power of boiler 5, four wind speed measuring devices 15, 16, 17 and 18 are set, and a wind speed measuring device is correspondingly set on each pipeline between the burners 19, 20, 21 and 22 and the pulverized coal airflow distribution device 10 to detect the air volume of the cold and hot primary air and pulverized coal mixture entering the corresponding burners 19, 20, 21 and 22, so as to facilitate online leveling of the burner power of boiler 5.

[0049] To detect the wind speed of the hot and cold primary air after the hot and cold primary air are mixed, the boiler deep peak-shaving combustion adjustment system specifically further includes: a wind speed detection device 6 disposed on the gas equalizing pipe A, for detecting the wind speed of the mixed gas of the hot and cold primary air flowing through the gas equalizing pipe A. Detecting the wind speed of the hot and cold primary air before carrying the pulverized coal into the pulverized coal airflow distribution device 10 facilitates personnel to derive the air volume based on the wind speed, thereby facilitating adjustment of the number of coal mills 7 required for actual operation based on the obtained air volume, thereby improving the operational combustion stability of the boiler 5.

[0050] In one embodiment, Figure 6 As shown, specifically, the wind speed detection device 6 includes: a backrest tube 61, a protective sleeve 62 and a driving mechanism 63;

[0051] The protective sleeve 62 is cylindrical with one end open, and the backrest tube 61 is arranged in the protective sleeve 62. The backrest tube 61 is used to detect wind speed;

[0052] A detection hole is opened on the wall of the gas equalizing pipe A, and the open end of the protective sleeve 62 extends into the gas equalizing pipe A through the detection hole. The protective sleeve 62 can move along the extension direction of the detection hole;

[0053] The driving mechanism 63 is used to drive the protection sleeve 62 to move along the extending direction of the detection hole.

[0054] The wind speed detection device 6 further includes: a back-blowing mechanism 64;

[0055] A back-blowing hole is formed at one end of the air equalizing pipe A exposed outside the detection hole, and the back-blowing mechanism 64 blows air into the protective sleeve 62 through the back-blowing hole to purge the backrest pipe 61 disposed in the protective sleeve 62 .

[0056] A wind speed detection device 6 is provided on the air equalizing pipe A. The measurement principle of the wind speed detection device 6 is the Pitot tube test principle. For ease of use, the driving mechanism 63 includes a driving guide rail and a motor. The extension direction of the guide rail is the same as the extension direction of the detection hole. The protective sleeve 62 is slidably installed on the driving guide rail. The motor drives the protective sleeve 62 to move on the guide rail so that the protective sleeve 62 can move in the extension direction of the detection hole. In the process of the protective sleeve 62 moving along the extension direction of the detection hole, the backrest tube 61 arranged in the protective sleeve 62 is driven to move, so that the backrest tube 61 can extend into the detection hole or exit the detection hole with the protective sleeve 62 to detect the hot and cold inside the air equalizing pipe A. When the wind speed of the primary wind is measured, the protective sleeve 62 carries the backrest tube 61 into the detection hole to detect the wind speed of the cold and hot primary winds flowing through the air equalizing pipe A. After the detection is completed, in order to avoid the impact of the cold and hot primary winds on the backrest tube 61, the protective sleeve 62 carries the backrest tube 61 to exit the detection hole. The wind speed measuring devices 15, 16, 17 and 18 may have the same structure as the wind speed detection device 6. After using the wind speed detection device 6 or the wind speed measuring devices 15, 16, 17 and 18 for a period of time, in order to avoid clogging of the backrest tube 61, a back-blowing mechanism 64 is provided to blow air into the protective sleeve 62 to purge the backrest tube 61 to avoid clogging of the backrest tube 61 and ensure the detection accuracy of the backrest tube 61.

[0057] like Figure 5 As shown, the boiler deep peak-shaving combustion adjustment system can also be provided with a signal processing unit 23 and a signal conversion module 24. The signal processing unit 23 and the signal conversion module 24 are connected by signal. The signal processing unit 23 is connected by signal with the wind speed measuring devices 15, 16, 17 and 18. The wind speed measuring devices 15, 16, 17 and 18 transmit the detected wind speeds of the cold and hot primary air and pulverized coal in the corresponding pipelines to the signal processing unit 23. The signal processing unit 23 calculates the wind speeds V1 and V2 in the corresponding pipelines. , V3 and V4, and calculate the average wind speed of the four pipelines. When the wind speed deviation in a certain pipeline is greater than 5% of the average wind speed, the adjustment instruction is transmitted to the corresponding combustion regulating valve through the signal conversion module 24 to adjust the opening size of the combustion regulating valve. After the adjustment, the wind speed in the corresponding pipeline is detected again by the wind speed measuring devices 15, 16, 17 and 18 until the wind speed deviation in the pipeline is less than 5% of the average wind speed. In this way, the combustion power leveling work of burners 19, 20, 21 and 22 is completed, and the combustion of the burner of boiler 5 is leveled, which is beneficial to the full combustion and burnout of the pulverized coal airflow in the furnace during deep peak regulation of the boiler, thereby improving the combustion stability and low-load operation economy.

[0058] The coal mill inlet air mixing and equalizing device provided by the present invention is provided with an equalizing heat conduction box, and hot primary air ducts and cold primary air ducts are arranged in layers and staggered in the equalizing heat conduction box. Multiple guide plates are arranged at the cold air outlet of each layer of cold primary air duct. The flow direction of the cold primary air flowing out of the cold air outlet is adjusted by the multiple guide plates. When the hot primary air and cold primary air flow through the corresponding hot primary air duct and cold primary air duct respectively, heat exchange occurs with the hot primary air or cold primary air flowing in the adjacent hot primary air duct or cold primary air duct, so that the temperature difference between the hot primary air and the cold primary air is reduced. In this way, the temperature of the hot primary air when flowing out of the hot air outlet and the temperature of the cold primary air when flowing out of the cold air outlet are similar. After the two enter the equalizing pipe and mix, the flow field distribution of the hot and cold primary air formed is more uniform and stable. The present invention also provides a boiler deep peak-shaving combustion adjustment system. The coal mill air inlet mixing and equalizing device and boiler deep peak-shaving combustion adjustment system provided by the present invention not only solve the problem of poor flow field uniformity after mixing of hot primary air and cold primary air in the prior art, but also improve the combustion performance of subsequent boilers.

[0059] The above describes in detail the optional implementation methods of the embodiments of the present invention in conjunction with the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above implementation methods. Within the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical solutions of the embodiments of the present invention, and these simple modifications all fall within the scope of protection of the embodiments of the present invention.

[0060] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not further describe various possible combinations.

[0061] In addition, various implementations of the embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the embodiments of the present invention, they should also be regarded as the contents disclosed in the embodiments of the present invention.

Claims

1. A coal mill air inlet mixing and equalizing device for mixing hot primary air and cold primary air and then conveying them to the powder outlet of the coal mill (7), characterized in that: The coal mill inlet air mixing and flow balancing device comprises: The flow-equalizing heat conduction box (3) has a plurality of hot primary air ducts (31) and cold primary air ducts (32), wherein the hot primary air ducts (31) and the cold primary air ducts (32) are arranged in layers, staggered, and parallel to each other, wherein the hot primary air enters the corresponding hot primary air duct (31) through the hot air inlet and flows out from the corresponding hot air outlet, and the cold primary air enters the corresponding cold primary air duct (32) through the cold air inlet and flows out from the corresponding cold air outlet, wherein the hot primary air exchanges heat with the cold primary air flowing in the cold primary air duct (32) adjacent to the hot primary air duct (31) when flowing through the hot primary air duct (31); An air equalizing pipe (A), one end of which is connected to the hot air outlet of each hot primary air duct (31) and the cold air outlet of each cold primary air duct (32), and the other end of which is connected to the powder outlet of the coal mill (7); A plurality of guide plates (4) are arranged at the cold air outlet of each cold primary air duct (32), and the flow direction of the cold primary air flowing out of the cold air outlet is controlled by the plurality of guide plates (4).

2. The coal mill inlet air mixing and flow balancing device according to claim 1, characterized in that: The flow-equalizing heat-conducting box (3) comprises: a plurality of outer box plates (34) and a plurality of partition plates (35); the plurality of outer box plates (34) enclose the flow-equalizing heat-conducting box (3); the plurality of partition plates (35) are arranged in parallel with each other in the flow-equalizing heat-conducting box (3), and the flow-equalizing heat-conducting box (3) is divided into a plurality of hot primary air ducts (31) and a plurality of cold primary air ducts (32); the hot air inlet and the hot air outlet of the hot primary air duct (31) and the cold air inlet and the cold air outlet of the cold primary air duct (32) are opened on the corresponding outer box plates (34).

3. The coal mill inlet air mixing and equalizing device according to claim 2, characterized in that: The hot air inlet of the hot primary air duct (31) and the cold air inlet of the cold primary air duct (32) are respectively opened on two adjacent outer box plates (34), and the hot air outlet of the hot primary air duct (31) and the cold air outlet of the cold primary air duct (32) are opened on the same outer box plate (34).

4. The coal mill inlet air mixing and equalizing device according to claim 1, characterized in that: The cold air inlet and the cold air outlet of each cold primary air duct (32) are respectively opened on two adjacent outer box plates (34).

5. The coal mill inlet air mixing and flow balancing device according to claim 1, characterized in that: Each guide plate (4) is an arc-shaped plate.

6. The coal mill inlet air mixing and flow balancing device according to claim 1, characterized in that: The coal mill inlet air mixing and flow balancing device further comprises: A hot air source delivers hot primary air to each hot primary air duct (31) of the flow-uniform heat transfer box (3) through a hot primary air duct (1); The cold air source delivers cold primary air to each cold primary air duct (32) of the flow-balanced heat transfer box (3) through the cold primary air duct (2).

7. A boiler deep peak-shaving combustion adjustment system, comprising a boiler (5), a coal mill (7), a coal feeder (8) and a coal drop pipe (9), characterized in that: The boiler deep peak-shaving combustion adjustment system further includes: a coal mill inlet air mixing and equalizing flow device according to any one of claims 1-6.

8. The boiler deep peak shaving combustion adjustment system according to claim 7, characterized in that: The boiler deep peak-shaving combustion adjustment system further comprises: a wind speed detection device (6) provided on the gas equalizing pipe (A), for detecting the wind speed of the mixed gas of the hot primary air and the cold primary air flowing through the gas equalizing pipe (A).

9. The boiler deep peak shaving combustion adjustment system according to claim 8, characterized in that: The wind speed detection device (6) comprises: a backrest tube (61), a protective sleeve (62) and a driving mechanism (63); The protective sleeve (62) is cylindrical with one end open, the backrest tube (61) is arranged in the protective sleeve (62), and the backrest tube (61) is used to detect wind speed; A detection hole is provided on the wall of the gas equalizing pipe (A), and the open end of the protective sleeve (62) extends into the gas equalizing pipe (A) through the detection hole, and the protective sleeve (62) is movable along the extension direction of the detection hole; The driving mechanism (63) is used to drive the protective sleeve (62) to move along the extension direction of the detection hole.

10. The boiler deep peak shaving combustion adjustment system according to claim 9, characterized in that: The wind speed detection device (6) further includes: a back-blowing mechanism (64); A back-blowing hole is provided at one end of the air equalizing pipe (A) exposed outside the detection hole, and the back-blowing mechanism (64) blows air into the protective sleeve (62) through the back-blowing hole to purge the backrest pipe (61) arranged in the protective sleeve (62).

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