Secondary air rigidity and tangent circle double-adjusting device of tangent circle boiler

Abstract

The utility model discloses a secondary air rigidity and tangent circle double-adjusting device of a tangent circle boiler, which belongs to the technical field of boiler combustion and comprises a secondary air nozzle and an adjusting baffle plate, a partition plate is vertically arranged on the inner wall of the boiler inner end of the secondary air nozzle, the partition plate is rotatably connected with the adjusting baffle plate through a rotating shaft, and the adjusting baffle plate is rotatably connected with the secondary air nozzle. And one end of the rotating shaft extends out of the secondary air nozzle and is connected with a transmission assembly. The adjusting baffle is arranged in the secondary air nozzle and is connected with the external air cylinder through the rotating shaft, the crank and the connecting rod, so that the air cylinder drives the adjusting baffle to continuously adjust the angle on any side in an online manner, and the size of a tangent circle and the rigidity and the speed of jet flow are adaptively adjusted; a series of problems of low-load partial combustion, high pollutant emission, coking and the like of the boiler are effectively avoided, and the coal adaptability of the boiler is improved; the small holes are formed in the adjusting baffle, it is guaranteed that airflow still passes through the blocked side of the nozzle, high-temperature burning loss is prevented, and the service life of the nozzle is prolonged.

Description

Technical Field

[0001] This utility model relates to the field of boiler combustion technology, and in particular to a dual adjustment device for the rigidity and tangentiality of secondary air in a tangential boiler. Background Technology

[0002] With the rapid development of my country's economy and the continuous growth of energy demand, tangential boilers, due to their high combustion efficiency and low pollutant emissions, occupy an important proportion in the thermal power market. In the aerodynamic field of a tangential boiler, secondary air plays a dominant role, influencing the boiler's combustion characteristics and playing a crucial role in the entire power generation process.

[0003] With the increase in new energy power generation, flexible peak shaving of thermal power units has become a routine operation. During deep peak shaving operation, the boiler load is low and the pressure of the secondary air box is low, resulting in poor rigidity and wind speed of the secondary air. This can easily cause a series of problems such as actual tangential deviation of the boiler, low boiler efficiency, inability to form effective combustion, high nitrogen oxides, high pollutant emissions, uneven burning in the furnace, flame wall scorching, and coking of the water-cooled wall.

[0004] Furthermore, once the burner design and installation of a tangentially circular boiler are completed, the size of the tangential circle inside the furnace is fixed, and its combustion characteristics will not change significantly. Generally speaking, a larger tangential circle is beneficial for combustion but unfavorable for coals prone to coking, and is suitable for coals with poor combustion characteristics; a smaller tangential circle results in incomplete combustion but is less prone to flame wall burning and has good anti-coking ability, making it suitable for high-alkali coals and low-ash-fusion-point coals with good calorific value. Therefore, conventional tangentially circular boilers cannot effectively cope with complex and varied coal types and have poor adaptability.

[0005] Based on the above-mentioned shortcomings, a dual-adjustment device for the rigidity and tangentiality of the secondary air in a tangential boiler is proposed. Utility Model Content

[0006] The purpose of this invention is to provide a dual-adjustment device for the rigidity and tangentiality of the secondary air in a tangential boiler, in order to solve the problems in the prior art.

[0007] To achieve the above objectives, this utility model provides a dual adjustment device for the rigidity and tangentiality of secondary air in a tangential boiler, including a secondary air nozzle and an adjustment baffle. A partition plate is vertically arranged on the inner wall of the furnace end of the secondary air nozzle. The partition plate is rotatably connected to the adjustment baffle plate via a rotating shaft. One end of the rotating shaft extends out of the secondary air nozzle and is connected to a transmission component.

[0008] Preferably, the adjusting baffle has small holes.

[0009] Preferably, a gap is left between the adjusting baffle and the inner wall of the secondary air nozzle.

[0010] Preferably, the transmission assembly includes a crank, a connecting rod, and a cylinder, with one end of the crank fixedly connected to one end of the rotating shaft, and the other end of the crank rotatably connected to one end of the connecting rod.

[0011] Preferably, the other end of the connecting rod is rotatably connected to the moving end of the cylinder.

[0012] Therefore, the present invention, employing the above-described structure, provides a dual adjustment device for the rigidity and tangentiality of secondary air in a tangential boiler, which has the following beneficial effects:

[0013] (1) By setting an adjusting baffle inside the secondary air nozzle and connecting it to an external cylinder via a rotating shaft, crank, and connecting rod, continuous online adjustment of the adjusting baffle to any side angle is achieved. The structure is simple and the operation is convenient. The change of the adjusting baffle angle can, on the one hand, make adaptive adjustments to the rigidity and velocity of the secondary air nozzle jet according to the actual operating state of the boiler. Especially when the boiler is under low load, the rigidity and velocity of the secondary air can be improved by adjusting the baffle opening, thereby increasing the flame penetration and combustion organization capabilities, effectively avoiding a series of problems such as low boiler efficiency, high pollutant emissions, uneven furnace burning, skewed tangential circle, and coking. On the other hand, the change of the baffle angle will affect the flow area and jet center of the secondary air nozzle, realizing that the secondary air tangential circle can be adjusted between the minimum and maximum tangential circle diameters. The tangential circle size can be adjusted in a targeted manner according to the changes in coal type to seek the optimal combustion of the boiler and improve the coal type adaptability of the boiler.

[0014] (2) By opening small holes on the adjusting baffle, airflow is still allowed to pass through the side of the secondary air nozzle that is blocked, thereby cooling the secondary air nozzle, preventing high temperature burn-out, and extending the service life of the nozzle.

[0015] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0016] Figure 1 This is a front view of the structure of an embodiment of the present utility model;

[0017] Figure 2 This is a top view of the structure of an embodiment of the present utility model;

[0018] Figure 3 This is a schematic diagram of the initial state tangent circle of an embodiment of the present invention;

[0019] Figure 4 This is a top view of the structure in the maximum tangent circle state of an embodiment of this utility model;

[0020] Figure 5 This is a schematic diagram of the maximum tangent circle of an embodiment of the present invention;

[0021] Figure 6 This is a top view of the minimum tangent circle state structure of an embodiment of this utility model;

[0022] Figure 7 This is a schematic diagram of the smallest tangent circle of an embodiment of the present invention;

[0023] Figure label:

[0024] 1. Secondary air nozzle; 2. Adjusting baffle; 3. Divider plate; 4. Rotating shaft; 5. Transmission assembly; 51. Crank; 52. Connecting rod; 53. Cylinder; 6. Small hole. Detailed Implementation

[0025] The technical solution of this utility model will be further described below with reference to the accompanying drawings and embodiments.

[0026] Unless otherwise defined, the technical or scientific terms used in this utility model shall have the ordinary meaning understood by one of ordinary skill in the art to which this utility model pertains. The terms "first," "second," and similar terms used in this utility model do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0027] Example

[0028] like Figures 1-2 As shown, the present invention provides a tangential boiler secondary air rigidity and tangential dual adjustment device, including a secondary air nozzle 1 and an adjustment baffle 2. The secondary air nozzle 1 is installed at the corner of the tangential boiler, with one side connected to the wind box and the other side facing into the furnace, for sending the airflow from the wind box into the furnace.

[0029] A partition plate 3 is vertically installed on the inner wall of the furnace end of the secondary air nozzle 1. The partition plate 3 is used to divide the internal space of the secondary air nozzle 1 into two parts and guide the jet. The partition plate 3 is preferably made of stainless steel. Its furnace end is flush with the nozzle end face and is vertically welded to the inner wall of the secondary air nozzle 1. In order to ensure the rigidity of the jet after separation, the length of the partition plate 3 is preferably close to the depth of the secondary air nozzle 1.

[0030] The partition plate 3 is rotatably connected to the adjusting baffle 2 via a rotating shaft 4. One end of the rotating shaft 4 extends out of the secondary air nozzle 1 and is connected to a transmission assembly 5. The transmission assembly 5 includes a crank 51, a connecting rod 52, and a cylinder 53. One end of the crank 51 is fixedly connected to one end of the rotating shaft 4, and the other end of the crank 51 is rotatably connected to one end of the connecting rod 52. The other end of the connecting rod 52 is rotatably connected to the moving end of the cylinder 53. Therefore, the moving end of the cylinder 53 drives the connecting rod 52 to make lateral movements, which are then converted into rotational movements by the crank 51. This causes the rotating shaft 4 to drive the adjusting baffle 2 to rotate, changing the angle of the adjusting baffle 2 and thus changing the flow area on the corresponding side. This allows for adjustment of the corresponding secondary air rigidity, flow velocity, and tangential circle size.

[0031] The adjusting baffle 2 has a small hole 6 to ensure that a small amount of airflow always passes through the side of the secondary air nozzle 1 that is blocked, so as to prevent the blocked secondary air nozzle 1 from burning due to lack of cooling; a gap is left between the adjusting baffle 2 and the inner wall of the secondary air nozzle 1 to prevent dust accumulation or deformation from causing the adjusting baffle 2 to rotate and get stuck. The gap is preferably 3~5mm.

[0032] The following section details the adjustment methods for secondary air rigidity, flow rate, and tangential size by installing four such dual-adjustment devices for secondary air rigidity and tangential size at the corners of the tangential boiler:

[0033] 1) such as Figures 2-3 As shown, this is the initial state when the adjusting baffle 2 is in the center position of the secondary air nozzle 1. At this time, the adjusting baffle 2 will not change the jet rigidity, velocity and the size of the tangent circle. Under the combined action of the secondary airflow at the four corners, a rotating airflow is formed, forming an imaginary tangent circle in the furnace with a diameter of ØL1.

[0034] 2) such as Figures 4-5 As shown, the tangent circle is adjusted to its maximum state. At this time, the adjusting baffle 2 closes the secondary air nozzle 1 channel on one side, the flow area at the secondary air nozzle 1 decreases, the flow velocity increases, the velocity increases the rigidity of the airflow, and the anti-deflection ability and penetration increase; at the same time, the jet center moves outward compared to the initial state 1). Therefore, under the combined action of the secondary airflow at the four corners, the diameter of the tangent circle formed is increased to ØL2 compared to the initial state 1), which is conducive to combustion in the furnace and has a better effect on coal types that are not easy to burn and have low calorific value.

[0035] A small amount of airflow enters the blocked side through the small hole 6 on the regulating baffle 2 to cool the secondary air nozzle 1 and prevent the secondary air nozzle 1 from burning out due to lack of cooling.

[0036] 3) such as Figures 6-7As shown, the tangent circle is adjusted to its minimum state. At this time, the adjusting baffle 2 closes the secondary air nozzle 1 channel on the other side. The flow area at the secondary air nozzle 1 decreases, the flow velocity increases, and the increased velocity leads to increased airflow rigidity, increased resistance to deflection, and increased penetration. At the same time, the jet center shifts inward compared to the initial state 1). Therefore, under the combined action of the secondary airflows at the four corners, the diameter of the formed tangent circle is reduced to ØL3 compared to the initial state 1). The reduced tangent circle in the furnace can effectively alleviate flame wall brushing, reduce the heat load of the main combustion zone, inhibit the formation of nitrogen oxides, and prevent boiler coking and high-temperature corrosion of the water-cooled walls. A smaller tangent circle is more suitable for bituminous coal with high calorific value and high volatile matter, as well as high-alkali coal with strong coking and fouling characteristics.

[0037] A small amount of airflow enters the blocked side through the small hole 6 on the regulating baffle 2 to cool the secondary air nozzle 1 and prevent the secondary air nozzle 1 from burning out due to lack of cooling.

[0038] Furthermore, by applying the aforementioned tangential boiler secondary air rigidity and tangential dual adjustment device to actual production, the tangential circle can be continuously and freely adjusted between the minimum diameter ØL3 and the maximum diameter ØL2. The velocity and rigidity of the jet can also be adjusted online in both directions according to actual requirements. The operation is simple and provides a new online adjustment method for boiler combustion optimization, thereby seeking the optimal operating state that balances boiler safety and pollutant emissions under different coal types and loads.

[0039] Therefore, this utility model provides a dual-adjustment device for the rigidity and tangentiality of secondary air in a tangential boiler, employing the aforementioned structure. By installing an adjusting baffle inside the secondary air nozzle and connecting it to an external cylinder via a rotating shaft, crank, and connecting rod, continuous online adjustment of the adjusting baffle's angle on either side is achieved. The device is simple in structure and easy to operate. Changing the baffle angle allows for adaptive adjustments to the rigidity and velocity of the secondary air jet according to the actual operating conditions of the boiler. Especially at low boiler loads, adjusting the baffle opening can improve the rigidity and velocity of the secondary air, increasing flame penetration and combustion organization, effectively avoiding a series of problems such as low boiler efficiency, high pollutant emissions, uneven furnace combustion, tangential deviation, and coking. Furthermore, changing the baffle angle affects the flow area and jet center of the secondary air nozzle, allowing for adjustment of the secondary air tangentiality between the minimum and maximum diameters. This enables targeted adjustment of the tangentiality size based on coal type variations, seeking optimal boiler combustion and improving the boiler's coal adaptability.

[0040] By opening small holes in the adjusting baffle, airflow is still allowed to pass through the side of the secondary air nozzle that is blocked, thereby cooling the secondary air nozzle, preventing high-temperature burn-out, and extending the service life of the nozzle.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although the utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solution of this utility model, and these modifications or equivalent substitutions cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of this utility model.

Claims

1. A dual-adjustment device for the rigidity and tangentiality of secondary air in a tangential boiler, characterized in that: It includes a secondary air nozzle and an adjusting baffle. A partition plate is vertically arranged on the inner wall of the furnace end of the secondary air nozzle. The partition plate is rotatably connected to the adjusting baffle plate through a rotating shaft. One end of the rotating shaft extends out of the secondary air nozzle and is connected to a transmission component.

2. The dual adjustment device for the rigidity and tangentiality of secondary air in a tangential boiler according to claim 1, characterized in that: The adjusting baffle has small holes.

3. The dual adjustment device for the rigidity and tangentiality of secondary air in a tangential boiler according to claim 1, characterized in that: A gap is left between the adjusting baffle and the inner wall of the secondary air nozzle.

4. The dual adjustment device for the rigidity and tangentiality of secondary air in a tangential boiler according to claim 1, characterized in that: The transmission assembly includes a crank, a connecting rod, and a cylinder. One end of the crank is fixedly connected to one end of the shaft, and the other end of the crank is rotatably connected to one end of the connecting rod.

5. The dual adjustment device for the rigidity and tangentiality of secondary air in a tangential boiler according to claim 4, characterized in that: The other end of the connecting rod is rotatably connected to the moving end of the cylinder.

Images