Efficient pulverized coal separation device of coal mill

Abstract

The invention relates to the technical field of pulverized coal separation, and discloses an efficient pulverized coal separation device of a coal mill, which comprises a base for supporting the whole device, a powder blowing assembly, a secondary grinding assembly and a flow guide assembly for separating pulverized coal, a mounting frame used for mounting a coal grinding roller is mounted in the shell, a primary grinding groove is mounted at the top end of the base and used for being matched with the coal grinding roller to grind coal, a feeding pipe is fixedly connected to the side wall of the shell, and the bottom end of the feeding pipe is located above the primary grinding groove. Hot air of the air heater is specially conveyed to be matched with the rolling pieces, pulverized coal is blown away in multiple directions, the powder blowing efficiency is improved, automatic secondary grinding of coarse pulverized coal is achieved through driving of the first-stage grinding groove, the percent of pass and the utilization rate are improved, the adjustable flow deflectors can change centrifugal force according to needs, separation is accurately controlled, adaptability is enhanced, the system efficiency is optimized, and the cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of coal powder separation, and in particular to a coal powder high-efficiency separation device for a coal mill. Background Art

[0002] The medium-speed coal mill has an operating speed of 50-300r / min. It is suitable for grinding medium-hardness materials such as bituminous coal and lean coal, and is widely used in the power, metallurgy and other industries. When it is working, the raw coal is crushed into coal powder by the grinding roller on the grinding disc and is carried to the upper coal powder separator by the hot air flow. The coal powder separator can separate qualified coal powder from unqualified coarse coal powder by centrifugal, inertial and other means. The qualified coal powder is collected as the product, and the coarse coal powder is returned to the coal mill for further grinding, thereby ensuring that the particle size of the coal powder supplied to the boiler meets the requirements and improving the combustion efficiency.

[0003] The existing medium-speed coal mill still has the following defects when separating coal powder: first, when the grinding roller of the coal mill grinds coal in the grinding disc, the hot air flow that blows up mainly drives the coal powder to rise for drying and separation. Since the coal powder is deposited inside the grinding disc, the amount of coal powder carried by the hot air is limited due to the mutual adsorption between the coal powders and the limitation of the air flow direction that cannot be blown directly, and the separation efficiency is low; second, the separated coarse coal powder will be collected again and cannot be further ground and separated in a continuous manner; third, the angle of the cyclone guide plate for separating the coal powder is not adjustable, and the centrifugal force it can provide to the coal powder remains unchanged, and the adaptability to different coal powder coarseness requirements is poor; finally, since the feed pipe of the existing medium-speed coal mill is vertically arranged above the grinding disc, the fine coal powder can only enter the separation hood first and then be discharged by a number of conveying pipes. The fine coal powder is easy to form turbulence in the separation hood, which makes it difficult to quickly and centrally output the fine coal powder to the coal furnace for use after separation. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a high-efficiency coal powder separation device for a coal mill, which solves the problems of low coal powder separation efficiency and poor applicability and adjustment capability of the coal mill in the prior art.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: A coal powder high-efficiency separation device for a coal mill, comprising: a base for supporting the overall device, the top of the base is fixedly connected to a shell, a mounting frame for mounting a coal grinding roller is installed inside the shell, a primary grinding groove is installed at the top of the base, the primary grinding groove is used to grind coal in cooperation with the coal grinding roller, a feed pipe is fixedly connected to the side wall of the shell, and the bottom end of the feed pipe is located above the primary grinding groove;

[0006] A powder blowing assembly, the powder blowing assembly comprising a hot air blower installed on the outer wall of the base, the output end of the base is fixedly connected to a second air duct, the end of the second air duct is fixedly connected to an annular tube, the top of the annular tube is provided with a plurality of air holes, the top of the second air duct is connected to the first air duct, and the end of the first air duct is installed with a tumbling assembly;

[0007] A secondary grinding assembly, wherein the secondary grinding assembly is mounted above the mounting frame;

[0008] A flow guide component for separating coal powder is installed on the top inner wall of the shell.

[0009] Preferably, the tumbling assembly includes a connecting piece rotatably connected to the end of the first air duct, the first air duct is connected to the connecting piece, the outer wall of the connecting piece is fixedly connected to a bevel gear, the outer wall of the primary grinding groove is fixedly connected to a bevel gear ring, the bevel gear is meshingly connected to the bevel gear ring, and a plurality of tumbling plates are fixedly connected to the end of the connecting piece, and the interior of the tumbling plates is set as a stainless steel mesh.

[0010] Preferably, the tumbling plates are collectively formed into a spherical shape, and the tumbling plates are fitted into the groove of the primary grinding groove.

[0011] Preferably, the secondary grinding assembly includes a grinding block fixedly connected to the top of the mounting frame, a rotating shaft is fixedly connected to the middle of the top of the primary grinding groove, the top of the rotating shaft passes through the feed pipe and is fixedly connected to a grinding disc, a secondary grinding groove is opened inside the grinding block, the outer wall of the grinding disc is attached to the surface of the secondary grinding groove, and a separation cylinder is fixedly connected to the top of the grinding block.

[0012] Preferably, the top end of the grinding disc is fixedly connected with a conical seat.

[0013] Preferably, the guide assembly includes a plurality of guide vanes rotatably connected to the top of the separation cylinder, the tops of the guide vanes are fixedly connected to spur gears, the top inner wall of the shell is rotatably connected to a protective cover, the inner wall of the protective cover is fixedly connected to a spur gear ring, the spur gears are meshingly connected to the spur gear rings, and the outer walls of the spur gears are installed with adjustment assemblies.

[0014] Preferably, the adjustment assembly includes a transmission frame rotatably connected to the outer wall of the spur gear, an electric push rod is fixedly connected to the outer wall of the shell, and a driving end of the electric push rod is rotatably connected to the end of the transmission frame.

[0015] Preferably, a separation cover is fixedly connected to the top of the shell, and the separation cover is configured to be a funnel shape that is narrow at the top and wide at the bottom, and the top of the separation cover is used to be connected to the coal powder conveying pipeline.

[0016] Working principle: coal blocks enter the first-stage grinding groove through the feed pipe for grinding, and hot air is blown out by the hot air blower. The hot air enters the inside of the annular tube through the second air duct and blows upward from the air hole to transport the coal powder upward. At the same time, when the first-stage grinding groove rotates to grind, the bevel gear is driven to rotate through the bevel gear ring, thereby driving the overturning in the first-stage grinding groove, which can stir the coal powder in the first-stage grinding groove. During the process of rising and falling, the coal powder is blown away by a part of the hot air entering the first air duct and transported upward, which can avoid the deposition of coal powder in the grinding groove and improve the powder blowing efficiency. The coal powder generates centrifugal force through the guide vane above, and the transmission frame is deflected by the electric push rod, thereby driving the spur gear ring in the shield to rotate, and the coal powder is fed into the grinding groove. The first grinding groove drives the rotating shaft and the grinding disc to rotate at the same time. The deposited coal powder is ground for the second time between the grinding disc and the second grinding groove. The coal powder after the second grinding is discharged again through the gap between the grinding disc and the second grinding groove and is blown up by hot air for separation, so as to prevent the coal powder after the first separation from being processed continuously, thereby improving the overall separation efficiency.

[0017] The present invention provides a high-efficiency coal powder separation device for a coal mill, which has the following beneficial effects:

[0018] 1. The hot air generated by the hot air blower is transported through specially designed air ducts and annular pipes, and is matched with spherical tumbling plates with stainless steel mesh. The tumbling plates tumble in the primary grinding groove as the groove rotates, blowing away the coal powder in multiple directions and breaking the adsorption and deposition. Compared with the traditional unidirectional hot air powder, more coal powder can be separated from the grinding groove in time, significantly reducing residual accumulation, improving the grinding output and quality, and reducing equipment wear and energy consumption.

[0019] 2. The present invention drives the grinding disc to cooperate with the secondary grinding groove through the rotation of the primary grinding groove, so that the coarse coal powder is automatically recovered for secondary grinding, without the need for additional transfer and processing equipment, forming a coherent circulation system. Compared with equipment without this function, the final qualified rate of coal powder is greatly improved, the waste of unqualified emissions is reduced, the utilization rate of coal is improved, the adverse effects of coarse coal powder on combustion equipment are reduced, and the stable and efficient operation of the system is guaranteed.

[0020] 3. The present invention provides an adjustable angle guide plate, and realizes angle adjustment with the help of electric push rods, transmission frames, etc., which can change the centrifugal force of coal powder according to boiler requirements and coal characteristics, and accurately control the separation effect. It enhances the adaptability of the coal mill to different working conditions, effectively reduces incomplete combustion and energy waste caused by inappropriate coal powder coarseness, optimizes the operating efficiency and economy of the coal-fired system, and reduces the cost and time of component replacement and parameter adjustment.

[0021] 4. The feed pipe inlet of the present invention is reasonably located on the side of the shell, ensuring that the raw coal is accurately fed into the slot for grinding, avoiding affecting the narrow upper and wide lower funnel-shaped design of the separation cover, accelerating the rising airflow of the coal powder, reducing turbulence, and centrally and quickly guiding qualified coal powder to the conveying pipeline. Compared with the traditional structure, it improves the efficiency of coal powder collection and transportation, ensures timely and continuous supply, and strongly supports the stable operation of the combustion equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the internal structure of the housing of the present invention;

[0023] Figure 2 A perspective view of the present invention;

[0024] Figure 3 An exploded view of the internal structure of the housing of the present invention;

[0025] Figure 4 It is a schematic diagram of the structure of the flow guide assembly of the present invention;

[0026] Figure 5 It is a schematic diagram of the structure of the secondary grinding assembly of the present invention;

[0027] Figure 6 It is a schematic diagram of the structure of the tumbling assembly of the present invention.

[0028] Among them, 1. Shell; 2. Feed pipe; 3. Electric push rod; 4. First air duct; 5. Hot air blower; 6. Base; 7. Ring pipe; 8. Tumbling plate; 9. Primary grinding groove; 10. Mounting frame; 11. Separation cylinder; 12. Protective cover; 13. Separation cover; 14. Bevel gear ring; 15. Rotating shaft; 16. Grinding block; 17. Straight gear ring; 18. Straight gear; 19. Guide vane; 20. Transmission frame; 21. Grinding disc; 22. Conical seat; 23. Secondary grinding groove; 24. Connector; 25. Bevel gear; 26. Second air duct. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the specification of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Example:

[0031] Please refer to the attached Figure 1The embodiment of the present invention provides a coal powder high-efficiency separation device for a coal mill, including a base 6 for supporting the entire device, a shell 1 is fixedly connected to the top of the base 6, a mounting frame 10 for mounting a coal grinding roller is installed inside the shell 1, a primary grinding groove 9 is installed on the top of the base 6, and the primary grinding groove 9 is used to cooperate with the coal grinding roller to grind coal. The base 6 serves as the foundation of the entire device and provides stable support for the shell 1 and various internal components. The shell 1 forms a relatively closed space to prevent coal powder from overflowing and ensure the safe and orderly internal coal grinding and separation process. The mounting frame 10 is used to stably install the coal grinding roller so that it can work normally in the primary grinding groove 9. The primary grinding groove 9 is the place for the initial grinding of raw coal. The coal grinding roller rotates in the primary grinding groove 9 to squeeze the raw coal and crush it into coal powder, laying a foundation for subsequent separation, secondary grinding and other processes.

[0032] Please refer to the attached Figure 2 , Figure 3 and Figure 6 , a powder blowing component, the powder blowing component includes a hot air blower 5 installed on the outer wall of the base 6, the output end of the base 6 is fixedly connected to the second air duct 26, the end of the second air duct 26 is fixedly connected to the annular tube 7, the top of the annular tube 7 is provided with a plurality of air holes, the top of the second air duct 26 is connected to the first air duct 4, the end of the first air duct 4 is installed with a tumbling component, the tumbling component includes a connecting piece 24 rotatably connected to the end of the first air duct 4, the first air duct 4 is connected to the connecting piece 24, the outer wall of the connecting piece 24 is fixedly connected to the bevel gear ring 14, the bevel gear 25 is meshed with the bevel gear ring 14, the end of the connecting piece 24 is fixedly connected to a plurality of tumbling sheets 8, the interior of the tumbling sheet 8 is provided with a stainless steel mesh, the tumbling sheets 8 together form a spherical shape, and the tumbling sheet 8 fits in the groove of the first grinding groove 9.

[0033] Specifically, the hot air generated by the hot air blower 5 enters the second air duct 26 through the internal channel of the base 6, and a part of the hot air is blown upward through the air hole on the top of the annular tube 7, directly acting on the coal powder in the primary grinding groove 9, providing upward power to cause the coal powder to rise for separation, and the other part of the hot air enters the first air duct 4. When the primary grinding groove 9 rotates, the bevel gear ring 14 on its outer wall drives the bevel gear 25 meshing with it to rotate, thereby causing the connecting piece 24 to rotate, driving the spherical tumbling piece 8 to tumble in the primary grinding groove 9. During the tumbling process, the hot air is blown out from the stainless steel mesh inside the tumbling piece 8, blowing away the coal powder from different angles, and at the same time causing the coal powder to rise and fall in the groove, effectively The adsorption force and deposition state between the coal powders are broken, so that more coal powders can be carried up by the hot air. The powder blowing component is cleverly designed. The hot air conveying method combining the annular tube 7 and the first air duct 4, and the dynamic assistance of the tumbling plate 8, significantly improve the powder blowing efficiency. Compared with the traditional method of only relying on a single direction of hot air to carry powder, more coal powder can be timely separated from the grinding groove and enter the separation link, reducing the residual and accumulation of coal powder in the grinding groove, improving the grinding output and quality of the coal mill, and reducing the problems of equipment wear and increased energy consumption caused by coal powder deposition. In addition, the tumbling plate 8 with a stainless steel mesh structure can also play a role in preliminary screening and dispersion of coal powder to a certain extent.

[0034] Please see attached Figure 2 , Figure 3 and Figure 5 , a secondary grinding assembly, the secondary grinding assembly is installed above the mounting frame 10, the secondary grinding assembly includes a grinding block 16 fixedly connected to the top of the mounting frame 10, a rotating shaft 15 is fixedly connected to the middle of the top of the primary grinding groove 9, the top of the rotating shaft 15 passes through the feed pipe 2 and is fixedly connected to a grinding disc 21, a secondary grinding groove 23 is opened inside the grinding block 16, the outer wall of the grinding disc 21 is attached to the surface of the secondary grinding groove 23, the top of the grinding block 16 is fixedly connected to the separation cylinder 11, and the top of the grinding disc 21 is fixedly connected to the cone seat 22;

[0035] Specifically, when the primary grinding groove 9 rotates under power drive, the grinding disc 21 is driven to rotate synchronously through the rotating shaft 15. After the first grinding, the coal powder that does not meet the standards enters the separation cylinder 11 under the action of gravity and centrifugal force and is deposited downward in the gap between the grinding disc 21 and the secondary grinding groove 23. Since the grinding disc 21 and the secondary grinding groove 23 are closely fitted and move relative to each other, the deposited coal powder is subjected to secondary extrusion and grinding here to further refine the coal powder particles. The setting of the conical seat 22 helps to guide the distribution of the coal powder on the grinding disc 21, so that it enters the secondary grinding area more evenly, thereby improving the secondary grinding effect. The secondary grinding assembly realizes the automatic recovery and re-grinding of the coarse coal powder without the need for additional transportation and processing equipment, so that the coal grinding process forms a coherent and efficient circulation system. Compared with equipment without the secondary grinding function, the final qualified rate of coal powder is greatly improved, the emission and waste of unqualified coal powder is reduced, and the utilization rate of coal resources is improved. At the same time, it also reduces the wear and poor operation of subsequent combustion equipment caused by the direct emission of coarse coal powder, thereby ensuring the stable and efficient operation of the entire coal-fired system.

[0036] Please refer to the attached Figure 2 , Figure 3 and Figure 4 , a guide assembly for separating coal powder, the guide assembly is installed on the top inner wall of the shell 1, the guide assembly includes a plurality of guide vanes 19 rotatably connected to the top of the separation cylinder 11, the tops of the guide vanes 19 are fixedly connected with spur gears 18, the top inner wall of the shell 1 is rotatably connected with a shield 12, the inner wall of the shield 12 is fixedly connected with a spur gear ring 17, the spur gears 18 are meshed with the spur gear ring 17, the outer wall of the spur gear 18 is installed with an adjustment assembly, the adjustment assembly includes a transmission frame 20 rotatably connected to the outer wall of the spur gear 18, the outer wall of the shell 1 is fixedly connected with an electric push rod 3, and the driving end of the electric push rod 3 is rotatably connected to the end of the transmission frame 20.

[0037] Specifically, when the coal powder is lifted up by the hot air, it first passes through the guide vane 19. The guide vane 19 can rotate within a certain range. The transmission frame 20 is driven to move by the extension and contraction of the electric push rod 3, and then the spur gear 18 rotates along the spur gear ring 17 to adjust the angle of the guide vane 19. When the angle of the guide vane 19 changes, the centrifugal force and direction of the coal powder when passing through the guide vane 19 change. The coal powder that meets the standard is blown into the separation cover 13 under the action of appropriate centrifugal force, and the coal powder that does not meet the standard enters the separation cylinder under the action of a larger centrifugal force. 11 For secondary grinding, the angle-adjustable guide assembly enables the coal mill to adapt to different coal powder coarseness requirements. During the production process, the angle of the guide plate 19 can be flexibly adjusted according to the boiler combustion requirements or the characteristics of different coal types to accurately control the coal powder separation effect. This not only improves the adaptability of the coal mill to various working conditions, but also reduces the problems of incomplete combustion and energy waste caused by inappropriate coal powder coarseness, but also optimizes the operating efficiency and economy of the entire coal-fired system to a certain extent, and reduces the cost and time consumption caused by frequent replacement of coal mill parts or adjustment of process parameters.

[0038] Please see attached Figure 1 , Figure 2 and Figure 3 A feed pipe 2 is fixedly connected to the side wall of the shell 1, and the bottom end of the feed pipe 2 is located above the primary grinding groove 9. A separation cover 13 is fixedly connected to the top of the shell 1. The separation cover 13 is set to be a funnel shape that is narrow at the top and wide at the bottom. The top of the separation cover 13 is used to be connected to the coal powder conveying pipeline.

[0039] Specifically, the raw coal naturally falls into the primary grinding groove 9 through the feed pipe 2 by gravity for grinding. After the coal powder is separated, the coal powder that meets the standards is blown to the separation cover 13. Since the separation cover 13 is a funnel-shaped structure that is narrow at the top and wide at the bottom, its internal space gradually shrinks, and the air flow speed of the coal powder gradually accelerates during the rising process, which is conducive to quickly and centrally guiding the coal powder to the top where it is connected to the coal powder conveying pipeline, so as to facilitate the efficient delivery of qualified coal powder to subsequent use links. The reasonable position setting of the feed pipe 2 ensures that the raw coal can accurately fall into the primary grinding groove 9 for grinding operations, avoiding problems such as uneven grinding or equipment blockage caused by feed deviation, and the special funnel-shaped design of the separation cover 13 effectively improves the output condition of fine coal powder after separation. Compared with the traditional separation cover structure, it can reduce the turbulence phenomenon of coal powder in the cover, improve the collection and transportation efficiency of coal powder, and enable qualified coal powder to enter the coal powder conveying pipeline more quickly and stably, thereby ensuring the timeliness and continuity of coal powder supply, and providing strong support for the stable operation of subsequent combustion equipment.

[0040] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A coal powder high-efficiency separation device for a coal mill, characterized in that: include: A base (6) for supporting the overall device, the top of the base (6) being fixedly connected to a shell (1), a mounting frame (10) for mounting a coal grinding roller being installed inside the shell (1), a primary grinding groove (9) being installed at the top of the base (6), the primary grinding groove (9) being used to cooperate with the coal grinding roller to grind coal, a feed pipe (2) being fixedly connected to a side wall of the shell (1), the bottom end of the feed pipe (2) being located above the primary grinding groove (9); A powder blowing assembly, the powder blowing assembly comprising a hot air blower (5) mounted on the outer wall of a base (6), the output end of the base (6) being fixedly connected to a second air duct (26), the end of the second air duct (26) being fixedly connected to an annular tube (7), the top of the annular tube (7) being provided with a plurality of air holes, the top of the second air duct (26) being connected to a first air duct (4), the end of the first air duct (4) being provided with a tumbling assembly; A secondary grinding assembly, the secondary grinding assembly being mounted above the mounting frame (10); A flow guide component for separating coal powder, wherein the flow guide component is installed on the top inner wall of the shell (1).

2. The high-efficiency coal powder separation device for a coal mill according to claim 1, characterized in that: The tumbling assembly comprises a connecting piece (24) rotatably connected to the end of the first air duct (4), the first air duct (4) is communicated with the connecting piece (24), the outer wall of the connecting piece (24) is fixedly connected to a bevel gear (25), the outer wall of the primary grinding groove (9) is fixedly connected to a bevel gear ring (14), the bevel gear (25) is meshingly connected to the bevel gear ring (14), and the end of the connecting piece (24) is fixedly connected to a plurality of tumbling plates (8), the interior of the tumbling plates (8) being arranged as a stainless steel mesh.

3. The high-efficiency coal powder separation device for a coal mill according to claim 2, characterized in that: The tumbling plates (8) are collectively formed into a spherical shape, and the tumbling plates (8) are fitted into the groove of the primary grinding groove (9).

4. The high-efficiency coal powder separation device for a coal mill according to claim 1, characterized in that: The secondary grinding assembly comprises a grinding block (16) fixedly connected to the top of a mounting frame (10); a rotating shaft (15) is fixedly connected to the middle of the top of the primary grinding groove (9); the top of the rotating shaft (15) passes through the feed pipe (2) and is fixedly connected to a grinding disc (21); a secondary grinding groove (23) is provided inside the grinding block (16); the outer wall of the grinding disc (21) is attached to the surface of the secondary grinding groove (23); and a separation cylinder (11) is fixedly connected to the top of the grinding block (16).

5. The high-efficiency coal powder separation device for a coal mill according to claim 4, characterized in that: The top end of the grinding disc (21) is fixedly connected with a cone seat (22).

6. The high-efficiency coal powder separation device for a coal mill according to claim 4, characterized in that: The flow guide assembly comprises a plurality of flow guide vanes (19) rotatably connected to the top end of the separation cylinder (11); the top ends of the flow guide vanes (19) are fixedly connected to spur gears (18); the inner wall of the top end of the housing (1) is rotatably connected to a shield (12); the inner wall of the shield (12) is fixedly connected to a spur gear ring (17); the spur gears (18) are meshedly connected to the spur gear ring (17); and an adjustment assembly is installed on the outer wall of the spur gear (18).

7. The high-efficiency coal powder separation device for a coal mill according to claim 6, characterized in that: The adjustment assembly comprises a transmission frame (20) rotatably connected to the outer wall of the spur gear (18); an electric push rod (3) is fixedly connected to the outer wall of the housing (1); and a driving end of the electric push rod (3) is rotatably connected to the end of the transmission frame (20).

8. The high-efficiency coal powder separation device for a coal mill according to claim 1, characterized in that: A separation cover (13) is fixedly connected to the top of the shell (1), and the separation cover (13) is arranged in a funnel shape that is narrow at the top and wide at the bottom. The top of the separation cover (13) is used to be connected to a coal powder conveying pipeline.

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