A coal mill for thermal power plant

Abstract

The present invention relates to the technical field of coal mills, and in particular to a coal mill for a thermal power plant, comprising: a grinding disc that can rotate; a hydraulic pull rod, on which a support frame is provided, and the support frame is provided with a connecting frame; a grinding roller, which comprises a limiter fixedly arranged on the connecting frame, and a grinding member rotatably arranged on the connecting frame, the limiter and the grinding member being rotatably connected; a feed hood, which is arranged on the limiter; the limiter is provided with a feed trough; the grinding member is provided with a discharge trough. During feeding, the central area of ​​the equipment and the top of the grinding disc are free of obstructions. The conveying channel formed by the feed hood and the grinding member is convenient for adding coal and can also increase the space inside the equipment, which is convenient for the arrangement of the gas path. The formed conveying channel is in a relatively closed state. Qualified coal powder after grinding is not easy to enter the conveying channel, which is convenient for the subsequent separation of qualified coal powder. The equipment can have a larger gas flow channel without obstructions.

Description

Technical Field

[0001] The invention relates to the technical field of coal mills, in particular to a coal mill for a thermal power plant. Background Art

[0002] In order to make full use of coal, the coal in thermal power plants needs to be ground before use to facilitate the complete combustion of the coal.

[0003] The coal mill is composed of grinding rollers, grinding discs, hydraulic pull rods, fans, separators and other equipment. The grinding discs are driven by an electric motor with a reducer to rotate. The hydraulic pull rods are equipped with multiple grinding rollers, which can be raised and lowered by the hydraulic pull rods so that the grinding rollers fit the surface of the grinding disc. The rotation of the grinding disc makes the fitted grinding rollers rotate, and the grinding discs cooperate with the grinding rollers to grind and crush the coal to achieve fine crushing of the coal powder.

[0004] The crushed materials are lifted up by the high-speed airflow of the wind ring at the edge of the grinding disc. Qualified fine coal powder flows out with the air flow, and the heavier coal powder falls back on the grinding disc for secondary crushing to achieve the separation of coarse and fine powders.

[0005] When the existing coal mill is in operation, the feed is located at the center of the grinding disc and the feeding equipment is arranged on the top. This arrangement has the following disadvantages: it is easy to affect the internal gas path, which affects the airflow to discharge qualified coal powder, is not conducive to the separation of coal powder, and because the feed needs to be in an open state, coal powder is easy to escape through the feed port. Therefore, a coal mill for a thermal power plant is proposed. Summary of the invention

[0006] In view of the problem mentioned above or in the prior art that coal powder easily escapes through the feed port, the present invention is proposed.

[0007] Therefore, an object of the present invention is to provide a coal pulverizer for a thermal power plant.

[0008] In order to solve the above technical problems, the present invention provides the following technical solutions: a coal mill for a thermal power plant, comprising: a grinding disc, which is capable of rotating; a hydraulic pull rod, on which a support frame is provided, and a connecting frame is provided on the support frame; a grinding roller, which comprises a limiter fixedly arranged on the connecting frame, and a grinding member rotatably arranged on the connecting frame, and the limiter and the grinding member are rotatably connected; a feed hood, which is arranged on the limiter; a feed trough is provided on the limiter; and a discharge trough is provided on the grinding member.

[0009] As a preferred solution of the coal mill for thermal power plants of the present invention, wherein: the limiting member is provided with a support shaft, and the support shaft is fixedly connected to the connecting frame; the grinding member is provided with a connecting shaft, and the connecting shaft is rotatably connected to the connecting frame.

[0010] As a preferred embodiment of the coal mill for thermal power plants of the present invention, the grinding roller further comprises an eccentric shaft arranged in the grinding member, and the eccentric shaft is arranged to deviate from the rotation axis of the grinding member; the grinding roller further comprises an extrusion member rotatably arranged on the outer wall of the eccentric shaft; the extrusion member comprises a connecting sleeve rotatably arranged on the outer wall of the eccentric shaft, and a scraper ring arranged on the outer wall of the connecting sleeve; the scraper ring is provided with an arc-shaped limit groove; the grinding roller further comprises a sliding block rotatably arranged in the arc-shaped limit groove; the limit member is provided with a limit scraper; the limit scraper is slidably connected with the sliding block.

[0011] As a preferred solution of the coal mill for thermal power plants of the present invention, an extrusion surface is provided on the scraper ring.

[0012] As a preferred solution of the coal mill for thermal power plant of the present invention, the limiting scraper is provided with an inclined surface.

[0013] As a preferred solution of the coal mill for thermal power plants of the present invention, a material dropping channel is provided between the scraper rings.

[0014] As a preferred solution of the coal mill for thermal power plants of the present invention, a rolling surface is provided on the grinding element.

[0015] As a preferred solution of the coal mill for thermal power plants of the present invention, wherein: the rolling surface is provided with extrusion holes.

[0016] As a preferred solution of the coal mill for thermal power plant of the present invention, wherein: a grinding table is provided on the grinding disc, and a grinding surface is provided on the grinding table.

[0017] As a preferred solution of the coal mill for thermal power plants of the present invention, a conical cover is provided on the grinding table.

[0018] The beneficial effects of the coal mill for thermal power plants of the present invention are as follows: when feeding, there are no obstructions in the central area of ​​the equipment and above the grinding disc. The conveying channel formed by the feed cover and the grinding parts can not only facilitate the addition of coal, but also increase the space inside the equipment, which is convenient for the arrangement of the gas path. The formed conveying channel is in a relatively closed state. Qualified coal powder after grinding is not easy to enter the conveying channel, which is convenient for the subsequent separation of qualified coal powder. The equipment can have a larger gas flow channel, and the channel is unobstructed. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0020] Figure 1 This is a schematic diagram of the overall structure of a coal pulverizer used in a thermal power plant.

[0021] Figure 2 This is a schematic diagram of the structure of the grinding roller of the coal mill used in thermal power plants.

[0022] Figure 3 This is a schematic diagram of the structure of the grinding roller of a coal mill used in a thermal power plant in an exploded state.

[0023] Figure 4 This is a schematic diagram of the structure of the extrusion parts of the coal mill used in thermal power plants.

[0024] In the figure: 100, grinding disc; 101, grinding table; 101a, grinding surface; 102, conical cover; 200, hydraulic pull rod; 201, support frame; 202, connecting frame; 300, grinding roller; 301, limit piece; 301a, feed chute; 301b, support shaft; 301c, limit scraper; 301d, inclined surface; 302, grinding piece; 302a, connecting shaft; 302b, discharge chute; 302c, rolling surface; 302d, extrusion hole; 303, eccentric shaft; 304, extrusion piece; 304a, connecting sleeve; 304b, scraper ring; 304c, extrusion surface; 304d, arc limit groove; 304e, drop channel; 305, sliding block; 400, feed hood. DETAILED DESCRIPTION

[0025] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0026] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0027] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0028] Example 1, reference Figures 1 to 4, is the first embodiment of the present invention, which provides a coal mill for a thermal power plant, including a grinding disc 100, which can rotate; a hydraulic pull rod 200, on which a support frame 201 is provided, and a connecting frame 202 is provided on the support frame 201; the hydraulic pull rod 200 can control the support frame 201 to rise and fall; a grinding roller 300, which includes a limiter 301 fixedly arranged on the connecting frame 202, and a grinding member 302 rotatably arranged on the connecting frame 202, and the limiter 301 and the grinding member 302 are rotatably connected; it should be noted that a feed cover 400 is arranged on the limiter 301; it is used to add coal; a feed trough 301a is provided on the limiter 301; a discharge trough 302b is provided on the grinding member 302, and three feed troughs 301a are provided on the surface of the limiter 301, and are arranged in a circular array with equal spacing, and a plurality of discharge troughs 302b are provided, which are evenly arranged on the surface of the grinding member 302 away from the limiter 301.

[0029] Specifically, the limiting member 301 is provided with a supporting shaft 301 b, and the supporting shaft 301 b is fixedly connected to the connecting frame 202; the grinding member 302 is provided with a connecting shaft 302 a, and the connecting shaft 302 a is rotatably connected to the connecting frame 202.

[0030] When in use, the grinding roller 300 is controlled by the hydraulic pull rod 200 so that the grinding piece 302 is attached to the grinding disc 100. The pressure applied by the grinding piece 302 to the grinding disc 100 when attached is the grinding pressure. The grinding effect of the equipment can be adjusted by adjusting the grinding pressure. After the grinding piece 302 is controlled by the hydraulic pull rod 200 to rise away from the grinding disc 100, the pressure on the grinding disc 100 can be reduced when the device is not in use, thereby increasing the service life of the equipment. This part has the same effect as that brought about by the prior art, and therefore, it will not be repeated here.

[0031] The main differences of this equipment are as follows: coal is added through the feed cover 400. When the grinding disc 100 is working, the grinding piece 302 will rotate together due to contact, while the limiter 301 will not rotate. The feed cover 400 cooperates with the grinding piece 302 to form a conveying channel for adding coal. The coal enters the grinding piece 302 through the feed groove 301a on the limiter 301, and is discharged through the discharge groove 302b on the grinding piece 302 and falls on the grinding disc 100. Due to the rotation of the grinding piece 302, the coal is in a rolling state in the grinding piece 302, and is not easy to stick to each other, and can make it easier for the coal to enter different discharge grooves 302b by rolling, which is convenient for the discharge of the coal. After the coal falls on the grinding disc 100, the grinding disc 100 and the grinding piece 302 cooperate with each other to grind and crush the coal.

[0032] In summary, during feeding, there are no obstructions in the central area of ​​the equipment and above the grinding disc 100 of the present invention. The conveying channel formed by the feed hood 400 and the grinding piece 302 is convenient for adding coal and can also increase the space inside the equipment, which is convenient for the arrangement of the gas path. The formed conveying channel is in a relatively closed state, and qualified coal powder after grinding is not easy to enter the conveying channel, which is convenient for the subsequent separation of qualified coal powder. The equipment can have a larger gas flow channel without obstructions.

[0033] Example 2, reference Figure 1~Figure 4 , which is the second embodiment of the present invention. Different from the previous embodiment, the grinding roller 300 also includes an eccentric shaft 303 arranged in the grinding member 302, and the eccentric shaft 303 is arranged to deviate from the rotation axis of the grinding member 302; the grinding roller 300 also includes an extruding member 304 rotatably arranged on the outer wall of the eccentric shaft 303; the extruding member 304 includes a connecting sleeve 304a rotatably arranged on the outer wall of the eccentric shaft 303, and a scraper ring 304b arranged on the outer wall of the connecting sleeve 304a; in this embodiment, the extruding member 304 can rotate along the eccentric shaft 303, and the rotation of the extruding member 304 can stir and crush the coal material located in the grinding member 302. Through the eccentric setting, the gap between the surface of the extruding member 304 and the internal surface of the grinding member 302 can be continuously changed, thereby achieving preliminary crushing of the coal powder, avoiding agglomeration, and facilitating the discharge of the coal material from the discharge trough 302b.

[0034] An arc-shaped limit groove 304d is provided on the scraper ring 304b; the grinding roller 300 also includes a sliding block 305 rotatably arranged in the arc-shaped limit groove 304d; it should be noted that three scraper rings 304b are provided on the outer wall of the connecting sleeve 304a, and two adjacent scraper rings 304b are provided with an arc-shaped limit groove 304d, and two sliding blocks 305 are provided, which are symmetrically arranged in the arc-shaped limit grooves 304d on the two adjacent scraper rings 304b.

[0035] The limiting member 301 is provided with a limiting scraper 301 c ; the limiting scraper 301 c is slidably connected to the sliding block 305 , and the limiting scraper 301 c is slidably disposed between two symmetrically disposed sliding blocks 305 .

[0036] Specifically, the scraper ring 304b is provided with an extrusion surface 304c.

[0037] Furthermore, a slope 301d is provided on the limiting scraper 301c, and the setting of the slope 301d can improve the cleaning effect of the limiting scraper 301c on the inner wall of the grinding member 302.

[0038] A material dropping channel 304e is provided between the scraper rings 304b. The material dropping channel 304e is provided to facilitate the discharge of the material dropped between the scraper rings 304b and to move to the gap between the extrusion surface 304c and the inner surface of the grinding member 302.

[0039] The grinding member 302 is provided with a rolling surface 302c.

[0040] The rolling surface 302c is provided with extrusion holes 302d. It should be noted that there are a plurality of extrusion holes 302d, which are evenly distributed in a circle on the rolling surface 302c. The diameter of the extrusion holes 302d is smaller than the discharge groove 302b. The extrusion holes 302d are used to discharge fine coal powder from the grinding piece 302.

[0041] A grinding table 101 is disposed on the grinding disc 100 , and a grinding surface 101 a is disposed on the grinding table 101 .

[0042] A conical cover 102 is provided on the grinding table 101. The conical cover 102 is provided to facilitate guiding the coal powder so that it finally falls on the grinding surface 101a.

[0043] The rest of the structure is the same as that of Example 1.

[0044] When in use, the grinding table 101 rotates. Since the grinding surface 101a and the rolling surface 302c are in contact with each other, the grinding piece 302 will also rotate when the grinding table 101 rotates. Since the diameter of the extrusion hole 302d is smaller than the discharge groove 302b, the rolling surface 302c can have a certain buffering capacity during grinding. When too much coal powder is rolled, the coal powder can enter the grinding piece 302 through the extrusion hole 302d, thereby avoiding damage to the rolling surface 302c of the grinding piece 302 caused by excessive pressure, thereby increasing the service life of the equipment. At the same time, since there is a gap between the extrusion holes 302d, the part without the extrusion hole 302d can still achieve the effect of grinding and crushing.

[0045] The coal enters the grinding member 302 through the feed cover 400. Since the grinding member 302 rotates during grinding, the eccentric shaft 303 also rotates in a circular motion. The limit member 301 is in a fixed state, and the limit scraper 301c is in a fixed state. When the grinding member 302 rotates, the limit scraper 301c can scrape off the coal powder adhering to the inner wall, and the circular motion of the eccentric shaft 303 will drive the extruding member 304 to perform a circular extrusion motion in the grinding member 302. The sliding block 305 rotates in the arc-shaped limit groove 304d, and the sliding block 305 slides on the outer wall of the limit scraper 301c. Through the circumferential extrusion motion of the extruding member 304 in the grinding member 302, the scraper ring 304b can stir and mix the internal coal to avoid agglomeration. At the same time, due to the movement of the scraper ring 304b and the grinding member 302 The rotation of the scraper ring 304b can improve the discharge efficiency of the discharge trough 302b, and when the scraper ring 304b moves, the extrusion surface 304c will successively approach and move away from the inner wall of the grinding piece 302, thereby achieving the crushing and crushing of the coal powder. When the extrusion surface 304c fits the inner wall of the grinding piece 302, it can initially crush the internal coal and squeeze it out from the extrusion hole 302d, so that it falls on the grinding surface 101a for fine grinding, which can effectively avoid the blockage of the extrusion hole 302d. The movement of the scraper ring 304b can also avoid the blockage of the discharge trough 302b, and the setting of the drop channel 304e makes it easy for the coal falling in the scraper ring 304b to move to between the extrusion surface 304c and the inner wall of the grinding piece 302, so as to facilitate the discharge of the coal in the grinding piece 302. Therefore, preliminary grinding by the extrusion piece 304 can also improve the grinding efficiency.

[0046] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A coal mill for a thermal power plant, characterized in that: include, a grinding disc (100) which is capable of rotating; A hydraulic pull rod (200) having a support frame (201) disposed thereon, and a connecting frame (202) disposed on the support frame (201); A grinding roller (300), comprising a stopper (301) fixedly arranged on the connecting frame (202), and a grinding member (302) rotatably arranged on the connecting frame (202), wherein the stopper (301) and the grinding member (302) are rotatably connected; A feed cover (400) disposed on the limiting member (301); The limiting member (301) is provided with a feeding groove (301a); The grinding element (302) is provided with a discharge groove (302b); The limiting member (301) is provided with a support shaft (301b), and the support shaft (301b) is fixedly connected to the connecting frame (202); The grinding element (302) is provided with a connecting shaft (302a), and the connecting shaft (302a) is rotatably connected to the connecting frame (202); The grinding roller (300) further comprises an eccentric shaft (303) disposed in the grinding member (302), wherein the eccentric shaft (303) is disposed offset from the rotation axis of the grinding member (302); The grinding roller (300) further comprises a material extruding member (304) rotatably disposed on the outer wall of the eccentric shaft (303); The extruding member (304) comprises a connecting sleeve (304a) rotatably arranged on the outer wall of the eccentric shaft (303), and a scraping ring (304b) arranged on the outer wall of the connecting sleeve (304a); The scraper ring (304b) is provided with an arc-shaped limiting groove (304d); The grinding roller (300) further comprises a sliding block (305) rotatably arranged in the arc-shaped limiting groove (304d); The limiting member (301) is provided with a limiting scraper (301c); The limiting scraper (301c) and the sliding block (305) are slidably connected.

2. The coal mill for thermal power plant according to claim 1, characterized in that: The scraper ring (304b) is provided with an extrusion surface (304c).

3. The coal mill for thermal power plant according to claim 2, characterized in that: The limiting scraper (301c) is provided with an inclined surface (301d).

4. The coal mill for thermal power plant according to claim 3, characterized in that: A material dropping channel (304e) is provided between the scraper rings (304b).

5. The coal mill for a thermal power plant according to any one of claims 1 to 4, characterized in that: The grinding piece (302) is provided with a rolling surface (302c).

6. The coal mill for thermal power plant according to claim 5, characterized in that: The rolling surface (302c) is provided with a material extrusion hole (302d).

7. The coal mill for thermal power plant according to claim 6, characterized in that: A grinding table (101) is provided on the grinding disc (100), and a grinding surface (101a) is provided on the grinding table (101).

8. The coal mill for thermal power plant according to claim 7, characterized in that: A conical cover (102) is provided on the grinding table (101).

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