Coal mill pulverizing system capable of improving deep adjustment capacity

Abstract

The utility model relates to the technical field of combustion of coal-fired boilers, in particular to a coal mill pulverizing system capable of improving deep adjustment capacity, which comprises a pulverized coal pipe, a section pipe and an extension pipe are integrally connected onto the pulverized coal pipe, a heat insulation pipe sleeve is rotatably arranged in the section pipe, a spiral heating rod is fixedly arranged in the heat insulation pipe sleeve, and the spiral heating rod is connected with the extension pipe. A flap wheel is arranged in the extension pipe in a driving mode, an outer cover is arranged outside the extension pipe to cover the flap wheel in the circumferential direction, one end of the outer cover is hinged to the extension pipe, and the other end of the outer cover is in lock catch connection with the extension pipe. According to the system, pulverized coal can be evenly ignited and preheated through rotation of the spiral heating rod, ignition heat is reduced while conveying of the pulverized coal is guaranteed, the air-coal ratio can be optimized and controlled more finely through gear adjustment of a baffle of the system and hedging conveying of a designed impeller, and therefore the better reasonable proportion is achieved, and the coal-fired ratio is improved. And the combustion stability of the pulverized coal under low load is improved.

Description

Technical Field

[0001] This utility model relates to the field of coal-fired boiler combustion technology, and in particular to a coal mill pulverizing system that enhances deep-regulation capability. Background Technology

[0002] With the significant increase in the installed capacity of new energy in the power market, and the strong random fluctuations of new energy, the high proportion of new energy grid connection will lead to a significant increase in power generation fluctuations. In order to meet the grid demand, coal-fired power units will continue to adjust to wide loads, and deep peak shaving will become the norm in the future, which will have a significant impact on the economic and safe operation of the units. When large thermal power generating units perform deep peak shaving, there are problems such as low reheat steam temperature and air preheater outlet flue gas temperature, as well as water-cooled wall overheating.

[0003] In response, existing technology (publication number CN116878018A) discloses a coal pulverizing system that enhances deep adjustment capability. By setting up an air duct opening adjustment device, it can close the upper tube baffle when the boiler is operating at low load and the amount of coal fed into the furnace is reduced, thereby increasing the coal powder concentration in the primary air pipe and the primary air lower tube, and increasing the air velocity in the primary air pipe and the primary air lower tube. This reduces the energy center of the boiler combustion field, improves the tangential circular suction combustion effect of the boiler, lengthens the combustion path, and makes the combustion more stable and complete, thereby saving energy, reducing consumption, and reducing carbon emissions.

[0004] However, the coal pulverizing system disclosed in the prior art still has the following technical problems: under the background of deep peak shaving, the coal powder concentration and coal feed amount in the pulverizing pipe can only be adjusted by the baffle position. Under low load conditions, due to its own structural reasons, there is still an unreasonable air-coal ratio, and the coal powder concentration is difficult to control, resulting in unstable combustion. Summary of the Invention

[0005] The main purpose of this invention is to overcome the shortcomings of the existing technology and provide a coal grinding system with improved deep adjustment capability.

[0006] The technical solution adopted by this utility model to achieve its technical objective is: a coal mill pulverizing system for improving deep adjustment capacity, including a pulverizing pipe, wherein a section pipe and an extension pipe are integrally connected to the pulverizing pipe;

[0007] A heat insulation sleeve is rotatably installed inside the tube segment, and a spiral heating rod is fixedly installed inside the heat insulation sleeve.

[0008] The extension tube has an internal drive mechanism for a flap wheel, which is circumferentially covered by an outer cover. The flap wheel is driven by a servo motor. One end of the outer cover is hinged to the extension tube, and the other end is locked to the extension tube.

[0009] Preferably, both ends of the heat insulation sleeve are fixed inside the section tube by bearings; a toothed ring is fixedly sleeved at the middle end of the heat insulation sleeve, and one side of the toothed ring is driven by a drive motor and a drive gear, and meshes with the drive gear.

[0010] The segment tube and the toothed ring are provided with a connecting groove at the corresponding positions, through which the drive gear and the toothed ring can be meshed and connected, and the drive motor is fixedly installed on the outer wall of the segment tube.

[0011] Preferably, the extension tube is configured as a U-shaped tube, and the outer cover is configured as a U-shaped plate shell;

[0012] The other end of the extension tube and the outer cover is provided with a locking plate. The lock head passes through the locking plate and is fixed in the lock seat, thereby locking the other end of the extension tube and the outer cover together.

[0013] The locking plate is provided in two parts, one fixed to the extension tube and the other fixed to the outer cover. The locking head passes through the two locking plates and is locked in the locking seat, thereby locking the other end of the extension tube and the outer cover together.

[0014] Preferably, the lock seat is fixed on the extension tube, and the lock seat includes a box body, a ring body, a buckle plate, a fixing sleeve and a torsion spring;

[0015] The box body is fixed to the extension tube, the box body has an opening, the ring body is fixed inside the box body by a column, and the buckle plate flips inside and outside on the ring body with the cooperation of a fixing sleeve and a torsion spring.

[0016] The buckle plate is configured as a bent structure, and multiple buckles are evenly distributed on the ring body. The fixing sleeve is fixed to the inner side of the bent part of the buckle plate and is sleeved on the outer wall of the ring body. The torsion spring is fixedly installed between the fixing sleeve and the ring body, so that the buckle plate can overcome the tension of the torsion spring and rotate inward and outward on the ring body.

[0017] Preferably, the lock head includes a pull ring, a pull rod, and a lock disc;

[0018] The pull rod is configured as a T-shaped rod, and the pull ring and the locking disc are respectively fixed at both ends of the pull rod. After the locking disc passes through the locking plate and presses the buckle plate to flip inward, the buckle plate springs back to lock and fix the locking disc.

[0019] Preferably, the locking disc is configured as a frustum structure with smooth chamfered edges, and the maximum diameter of the locking disc is smaller than the maximum diameter of the pull rod.

[0020] That is, the maximum diameter of the locking disc is smaller than the diameter of the pull rod cross plate, which can prevent the pull rod cross plate from coming out of the locking plate after the locking disc passes through the locking plate.

[0021] Compared with the prior art, the beneficial effects of this utility model are:

[0022] This coal mill pulverizing system, designed for deep peak shaving in large thermal power units, innovatively adopts an optimized pulverizing system operation mode, supplemented by coal mill outlet pulverized coal pipe temperature deviation control. On one hand, it uses rotating spiral heating rods to uniformly preheat the pulverized coal for ignition, ensuring pulverized coal transmission while reducing ignition heat. On the other hand, through the system's built-in baffle adjustment and designed impeller counter-impact transmission, it can optimize and more precisely control the air-coal ratio, achieving a better and more reasonable proportion and improving the combustion stability of pulverized coal under low load. This, in turn, ensures safe and stable unit operation while avoiding problems such as low reheat steam temperature, low air preheater outlet flue gas temperature, and water-cooled wall overheating. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the main / sectional structure of a coal grinding system.

[0024] Figure 2 This is a schematic diagram of the lock base from below.

[0025] Figure 3 This is a cross-sectional view of the buckle plate, the fixing sleeve, and the torsion spring.

[0026] Figure 4 This is the front view of the lock.

[0027] in:

[0028] 1-Powder tube; 2-Section tube; 201-Drive gear; 202-Drive motor; 203-Insulation sleeve; 204-Gear ring; 205-Spiral heating rod; 3-Extension tube; 301-Outer cover; 302-Flap wheel; 4-Locking plate; 5-Locking seat; 501-Box body; 502-Ring body; 503-Snap plate; 504-Fixing sleeve; 505-Torsion spring; 6-Locking head; 601-Pull ring; 602-Pull rod; 603-Locking disc Detailed Implementation

[0029] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0030] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0031] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit its scope. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the present utility model. Example

[0032] Please see Figure 1-4 A coal mill pulverizing system for improving deep adjustment capacity includes a pulverizing pipe 1, on which a section pipe 2 and an extension pipe 3 are integrally connected;

[0033] A heat insulation sleeve 203 is rotatably installed inside the tube segment 2, and a spiral heating rod 205 is fixedly installed inside the heat insulation sleeve 203. Both ends of the heat insulation sleeve 203 are fixed inside the tube segment 2 by bearings. A toothed ring 204 is fixedly fitted at the middle end of the heat insulation sleeve 203. One side of the toothed ring 204 is driven by a drive motor 202 and a drive gear 201, and meshes with the drive gear 201. A connecting groove is provided at the corresponding position of the tube segment 2 and the toothed ring 204, allowing the drive gear 201 and the toothed ring 204 to mesh. The drive motor 202 is fixedly installed on the outer wall of the tube segment 2.

[0034] The extension tube 3 has an internal drive mechanism with a flap wheel 302, which is covered circumferentially by an outer cover 301. The extension tube 3 is a U-shaped tube, and the outer cover 301 is a U-shaped plate shell. The flap wheel 302 is driven by a servo motor. One end of the outer cover 301 is hinged to the extension tube 3, and the other end is locked to the extension tube 3.

[0035] The other end of the extension tube 3 and the outer cover 301 is provided with a locking plate 4. A locking head 6 passes through the locking plate 4 and is fixed in the locking seat 5, thereby locking the other end of the extension tube 3 and the outer cover 301 together. There are two locking plates 4, one fixed to the extension tube 3 and the other fixed to the outer cover 301. The locking head 6 passes through the two locking plates 4 and is locked in the locking seat 5, thereby locking the other end of the extension tube 3 and the outer cover 301 together.

[0036] Furthermore, in this embodiment, the lock base 5 is fixed to the extension tube 3. The lock base 5 includes a box body 501, a ring body 502, a buckle plate 503, a fixing sleeve 504, and a torsion spring 505. The box body 501 is fixed to the extension tube 3 and has an opening. The ring body 502 is fixed inside the box body 501 by a column. The buckle plate 503 flips inward and outward on the ring body 502 with the cooperation of the fixing sleeve 504 and the torsion spring 505. The buckle plate 503 is configured as a bent structure, and multiple buckle plates are evenly distributed on the ring body 502. The fixing sleeve 504 is fixed to the inner side of the bent part of the buckle plate 503 and is sleeved on the outer wall of the ring body 502. The torsion spring 505 is fixedly installed between the fixing sleeve 504 and the ring body 502, so that the buckle plate 503 can overcome the tension of the torsion spring 505 and flip inward and outward on the ring body 502.

[0037] Furthermore, in this embodiment, the lock head 6 includes a pull ring 601, a pull rod 602, and a lock disc 603; the pull rod 602 is configured as a T-shaped rod, the pull ring 601 and the lock disc 603 are respectively fixed at both ends of the pull rod 602, after the lock disc 603 passes through the lock plate 4 and presses the buckle plate 503 to flip inward, the buckle plate 503 then springs back to lock and fix the lock disc 603.

[0038] Furthermore, in this embodiment, the locking disc 603 is configured as a frustum structure with chamfered edges. The maximum diameter of the locking disc 603 is smaller than the maximum diameter of the pull rod 602. That is, the maximum diameter of the locking disc 603 is smaller than the diameter of the horizontal plate portion of the pull rod 602, which can prevent the horizontal plate portion of the pull rod 602 from coming out of the locking plate 4 after the locking disc 603 passes through the locking plate 4.

[0039] Specifically, in use, the pulverized coal passing through the pulverized coal pipe 1 is preheated by the spiral heating rod 205, and the flow rate of the pulverized coal is controlled by the opposing impellers 302 on the pulverized coal pipe 1. When performing deep peak shaving of large thermal power generating units, the pulverized coal is preheated to different temperatures by the temperature control of the spiral heating rod 205, and the temperature deviation of the pulverized coal pipe outlet is controlled. At the same time, the opposing rotation of the impellers 302 controls the conveying flow rate of the pulverized coal, making it easier to adjust and control precisely.

[0040] Additionally, when there is powder accumulation in the extension tube 3 and the outer cover 301, by pulling the pull ring 601, the lock disc 603 causes the buckle plate 503 to flip outward, thereby allowing the lock head 6 to be removed from the lock seat 5. After the lock head 6 is removed from the lock seat 5, the buckle plate 503 is reset under the action of the torsion spring 505, and the outer cover 301 can be opened at the same time, so as to facilitate cleaning of powder accumulation and maintenance of the flap wheels 302. The buckle plate 503 is then springed back to lock and fix the lock disc 603.

[0041] It should be noted that although the above embodiments have been described herein, this does not limit the scope of patent protection for this utility model. Therefore, any changes and modifications made to the embodiments described herein based on the innovative concept of this utility model, or equivalent structural, procedural, or functional transformations made using the content of this utility model's specification and drawings, directly or indirectly applying the above technical solutions to other related technical fields, are all included within the scope of protection of this utility model patent.

Claims

1. A coal mill pulverizing system with enhanced deep-adjustment capability, characterized in that: It includes a powder tube (1), on which a section tube (2) and an extension tube (3) are integrally connected; A heat insulation sleeve (203) is rotatably installed inside the section tube (2), and a spiral heating rod (205) is fixedly installed inside the heat insulation sleeve (203). The extension tube (3) is internally driven by a flap wheel (302), and the flap wheel (302) is circumferentially covered by an outer cover (301). One end of the outer cover (301) is hinged to the extension tube (3), and the other end is locked to the extension tube (3).

2. The coal mill pulverizing system for improving deep adjustment capacity according to claim 1, characterized in that: The two ends of the heat insulation sleeve (203) are fixed inside the section tube (2) by bearings; a toothed ring (204) is fixedly sleeved at the middle end of the heat insulation sleeve (203), and one side of the toothed ring (204) is driven by a drive motor (202) and a drive gear (201) and meshes with the drive gear (201).

3. A coal mill pulverizing system for improving deep adjustment capacity according to claim 1, characterized in that: The extension tube (3) is configured as a U-shaped tube, and the outer cover (301) is configured as a U-shaped plate shell; The other end of the extension tube (3) and the outer cover (301) is provided with a locking plate (4), and the locking head (6) passes through the locking plate (4) and is fixed in the lock seat (5) to lock the other end of the extension tube (3) and the outer cover (301).

4. A coal mill pulverizing system for improving deep adjustment capacity according to claim 3, characterized in that: The lock base (5) includes a box body (501), a ring body (502), a buckle plate (503), a fixing sleeve (504), and a torsion spring (505); The box body (501) has an opening, the ring body (502) is fixed inside the box body (501) by a column, and the buckle plate (503) flips inside and outside on the ring body (502) with the cooperation of the fixing sleeve (504) and the torsion spring (505).

5. A coal mill pulverizing system for improving deep adjustment capacity according to claim 4, characterized in that: The lock head (6) includes a pull ring (601), a pull rod (602), and a lock disc (603). The pull rod (602) is configured as a T-shaped rod. The pull ring (601) and the locking disc (603) are respectively fixed at both ends of the pull rod (602). After the locking disc (603) passes through the locking plate (4) and presses the buckle plate (503) to flip inward, the buckle plate (503) then springs back to lock the locking disc (603).

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