A high-efficiency pulverized coal separating device of a coal mill

Abstract

The application relates to the technical field of coal powder separation, and discloses a high-efficiency coal powder separation device of a coal mill, which comprises a base for supporting the whole device, a powder blowing assembly, a secondary powder grinding assembly and a flow guide assembly for separating coal powder, the top end of the base is fixedly connected with a shell, an installation frame for installing a coal grinding roller is arranged in the shell, a primary grinding groove is arranged at the top end of the base, the primary grinding groove is used for cooperating 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. The hot air of a hot air fan is sent to the special conveying cooperation rolling piece, the coal powder is blown in multiple directions, the blowing efficiency is improved, the primary grinding groove drives the automatic secondary grinding of the coarse coal powder, the qualified rate and the utilization rate are improved, the adjustable flow guide piece can change the centrifugal force according to requirements, the separation is accurately controlled, the adaptability is enhanced, the system efficiency is optimized, and the cost is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coal powder separation, in particular to a high-efficiency coal powder separation device of a coal mill. BACKGROUND

[0002] Medium-speed coal mill is a coal mill with a working speed of 50-300r / min, which is suitable for grinding medium-hard materials such as bituminous coal and lean coal, and is widely used in power, metallurgy and other industries. When working, raw coal is crushed into coal powder on the grinding disc by the grinding roller, and then the coal powder is carried to the upper coal powder separator by hot air flow. The coal powder separator can separate qualified coal powder from unqualified coarse coal powder through centrifugal force, inertia and other methods. The qualified coal powder is collected as a product, and the coarse coal powder is returned to the coal mill for further grinding, so as to ensure that the particle size of the coal powder supplied to the boiler meets the requirements and improve the combustion efficiency.

[0003] The existing medium-speed coal mill still has the following defects when separating coal powder: firstly, the grinding roller of the coal mill mainly drives the coal powder to rise for drying and separation by the hot air flow blown up when grinding coal in the grinding disc. Due to the deposition of coal powder in the grinding disc, the amount of coal powder carried by the hot air is limited due to the mutual adsorption between the coal powder and the limitation that the air flow direction cannot be directly blown, and the separation efficiency is low; secondly, the separated coarse coal powder is collected again and cannot be further ground and separated continuously; thirdly, the angle of the cyclone guide plate for separating coal powder is not adjustable, and the centrifugal force provided by the cyclone guide plate for coal powder is constant, so the adaptability is poor for different coal powder thickness requirements; finally, since the feed pipe of the existing medium-speed coal mill is vertically arranged above the grinding disc, fine coal powder can only enter the separation cover first and then be discharged by several conveying pipes. Fine coal powder is easy to form turbulent flow in the separation cover, which makes it difficult to concentrate and quickly output to the coal stove after separation. SUMMARY

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

[0005] To achieve the above purpose, the following technical scheme is adopted: a high-efficiency coal powder separation device of a coal mill, comprising: a base for supporting the whole device, a shell fixedly connected to the top end of the base, an installation frame installed in the inside of the shell for installing a grinding roller, a primary grinding groove installed at the top end of the base, the primary grinding groove being used for grinding coal in cooperation with the grinding roller, a feed pipe fixedly connected to the side wall of the shell, the bottom end of the feed pipe being located above the primary grinding groove;

[0006] The powder blowing assembly comprises a hot air blower mounted on the outer wall of the base, the output end of the base is fixedly connected with a second air pipe, the end of the second air pipe is fixedly connected with an annular pipe, a plurality of air holes are formed in the top of the annular pipe, the top of the second air pipe is communicated with a first air pipe, and the end of the first air pipe is mounted with a tumbling assembly.

[0007] The secondary grinding assembly is mounted above the mounting frame.

[0008] The flow guide assembly for separating coal powder is mounted on the inner wall of the top end of the shell.

[0009] Preferably, the tumbling assembly comprises a connecting piece rotatably connected to the end of the first air pipe, the first air pipe is communicated with the connecting piece, the outer wall of the connecting piece is fixedly connected with a bevel gear, the outer wall of the primary grinding groove is fixedly connected with a bevel gear ring, the bevel gear is meshingly connected with the bevel gear ring, the end of the connecting piece is fixedly connected with a plurality of tumbling pieces, and the inner part of the tumbling pieces is provided with a stainless steel mesh.

[0010] Preferably, the tumbling pieces are collectively composed of a spherical shape, and the tumbling pieces are attached in the groove of the primary grinding groove.

[0011] Preferably, the secondary grinding assembly comprises a grinding block fixedly connected to the top end of the mounting frame, a rotating shaft fixedly connected to the top end of the primary grinding groove, the top end of the rotating shaft penetrates into the feeding pipe and is fixedly connected with a grinding disc, a secondary grinding groove is formed in the inner part of the grinding block, the outer wall of the grinding disc is attached to the surface of the secondary grinding groove, and the top end of the grinding block is fixedly connected with a separation cylinder.

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

[0013] Preferably, the flow guide assembly comprises a plurality of flow guide pieces rotatably connected to the top end of the separation cylinder, the top end of each flow guide piece is fixedly connected with a straight gear, the top end of the shell is rotatably connected with a protective cover, the inner wall of the protective cover is fixedly connected with a straight gear ring, each straight gear is meshingly connected with the straight gear ring, and the outer wall of the straight gear is mounted with an adjusting assembly.

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

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

[0016] Working principle: The coal block enters the first grinding groove through the feeding pipe to be ground, hot air is blown out by the hot air blower, the hot air enters the inside of the annular pipe through the second air pipe and is blown upward through the air hole, the coal powder is transported upward, at the same time, the first grinding groove is rotated to drive the bevel gear to rotate, thereby driving the first grinding groove to overturn, so that the coal powder in the first grinding groove is stirred, the coal powder is blown away and transported upward by a part of the hot air entering the first air pipe in the process of rising and falling, the deposition of the coal powder in the grinding groove is avoided, the powder blowing efficiency is improved, the coal powder generates centrifugal force through the guide vane on the upper side, the transmission frame is driven by the electric push rod to deflect, thereby driving the straight tooth ring in the shroud to rotate, further driving the straight gear to rotate, the angle of the guide vane is deflected, the appropriate deflection angle is adjusted according to the requirement, the coal powder meeting the standard is blown to the inside of the separation cover after passing through the guide vane and is discharged to the conveying pipeline for utilization, the coal powder not meeting the standard is deposited in the separation cylinder under the action of the centrifugal force and is deposited in the inside of the grinding block, the first grinding groove drives the rotating shaft and the grinding disc to rotate at the same time, the deposited coal powder is ground again between the grinding disc and the second grinding groove, the coal powder after secondary crushing is discharged again between the grinding disc and the second grinding groove and is blown up by the hot air to be separated, the coal powder after primary separation is prevented from not being processed continuously, and the overall separation efficiency is improved.

[0017] The application provides a coal powder efficient separation device of a coal mill.

[0018] 1、The hot air generated by the hot air blower is transported through the specially designed air pipe and annular pipe, and is matched with the spherical tumbling vane with a stainless steel mesh, the tumbling vane tumbles in the first grinding groove while the groove rotates, the coal powder is blown away in multiple directions and the adsorption and deposition are broken, compared with the traditional single-direction hot air powder carrying, more coal powder can be separated from the grinding groove in time, the residual accumulation is significantly reduced, the grinding yield and quality are improved, and the equipment wear and energy consumption are reduced.

[0019] 2、The first grinding groove drives the grinding disc and the second grinding groove to cooperate, so that the coarse coal powder is automatically recycled and secondarily ground, without additional transfer and treatment equipment, a continuous circulation system is formed, compared with the equipment without the function, the final qualified rate of the coal powder is greatly improved, the waste of unqualified emission is reduced, the coal utilization rate is improved, the adverse effects of the coarse coal powder on the combustion equipment are reduced, and the stable and efficient operation of the system is ensured.

[0020] 3、The application sets the angle-adjustable guide vane, and the angle is adjusted by means of the electric push rod and the transmission frame, so that the centrifugal force of the coal powder can be changed according to the requirements of the boiler and the characteristics of the coal, and the separation effect is accurately controlled. The adaptability of the coal mill to different working conditions is enhanced, the insufficient combustion and energy waste caused by the unsuitable coal powder thickness are effectively reduced, the operation efficiency and economy of the coal combustion system are optimized, and the cost and time of part replacement and parameter adjustment are reduced.

[0021] 4、The feed pipe entrance of the present application is reasonably located at the side of the shell, which ensures the accurate entry of raw coal into the grinding slot, avoids affecting the design of the funnel-shaped separation cover with narrow top and wide bottom, accelerates the rising airflow of the coal powder, reduces the turbulence, and concentrates and quickly guides the qualified coal powder to the conveying pipeline, compared with the traditional structure, improves the coal powder collection and conveying efficiency, ensures timely and continuous supply, and effectively supports the stable operation of the combustion equipment. BRIEF DESCRIPTION OF DRAWINGS

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

[0023] Figure 2 It is a perspective view of the present application;

[0024] Figure 3 It is an exploded view of the internal structure of the shell of the present application;

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

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

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

[0028] Wherein, 1, shell;2, feed pipe;3, electric push rod;4, first air pipe;5, hot air blower;6, base;7, annular pipe;8, tumbling piece;9, primary grinding slot;10, mounting bracket;11, separation cylinder;12, guard;13, separation cover;14, bevel gear ring;15, rotating shaft;16, grinding block;17, straight tooth ring;18, straight gear;19, flow guide piece;20, transmission bracket;21, grinding disc;22, taper seat;23, secondary grinding slot;24, connecting piece;25, bevel gear;26, second air pipe. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present application will be described in detail below with reference to the drawings of the present application specification. Obviously, the described embodiments are only a part of the embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0030] Embodiment:

[0031] Please refer to the drawings of the present application Figure 1The embodiment of the present application provides a coal pulverizer high-efficiency separation device, which comprises a base 6 for supporting the whole device, a shell 1 fixedly connected to the top end of the base 6, a mounting frame 10 for mounting a coal grinding roller installed in the shell 1, and a primary grinding groove 9 installed at the top end of the base 6 and used for grinding coal in cooperation with the coal grinding roller, wherein the base 6 serves as the foundation of the whole device and provides stable support for the shell 1 and the internal components, the shell 1 forms a relatively closed space to prevent coal powder from overflowing and ensure the safe and orderly progress of the internal grinding and separation processes, the mounting frame 10 is used for stably mounting the coal grinding roller so that the coal grinding roller can normally work in the primary grinding groove 9, and the primary grinding groove 9 is a place for primary grinding of raw coal, and the coal grinding roller rotates and extrudes the raw coal in the primary grinding groove 9 to crush the raw coal into coal powder, thereby laying a foundation for subsequent separation, secondary grinding and other processes.

[0032] Please refer to the accompanying drawings Figure 2 、 Figure 3 and Figure 6 , the powder blowing assembly comprises a hot air blower 5 mounted on the outer wall of the base 6, the output end of the base 6 is fixedly connected with a second air pipe 26, the end of the second air pipe 26 is fixedly connected with an annular pipe 7, a plurality of air holes are formed in the top of the annular pipe 7, the top of the second air pipe 26 is communicated with a first air pipe 4, the end of the first air pipe 4 is provided with a tumbling assembly, the tumbling assembly comprises a connecting piece 24 rotatably connected to the end of the first air pipe 4, the first air pipe 4 is communicated with the connecting piece 24, the outer wall of the connecting piece 24 is fixedly connected with a bevel gear 25, the outer wall of the primary grinding groove 9 is fixedly connected with a bevel gear ring 14, the bevel gear 25 is meshed and connected with the bevel gear ring 14, the end of the connecting piece 24 is fixedly connected with a plurality of tumbling pieces 8, the inside of the tumbling piece 8 is provided with a stainless steel mesh, the tumbling pieces 8 are jointly formed into a spherical shape, and the tumbling pieces 8 are attached in the groove of the primary grinding groove 9.

[0033] Specifically, the hot air generated by the air heater 5 enters the second air pipe 26 through the internal passage of the base 6, and a part of the hot air blows upward through the air holes at the top of the annular pipe 7, directly acting on the coal powder in the first grinding groove 9 to provide upward power and promote the upward movement of the coal powder for separation. Another part of the hot air enters the first air pipe 4. When the first grinding groove 9 rotates, the bevel gear ring 14 on the outer wall of the first grinding groove 9 drives the bevel gear 25 engaged therewith to rotate, thereby driving the connecting piece 24 to rotate and driving the ball-shaped tumbling piece 8 to tumble in the first grinding groove 9. In the tumbling process, hot air is blown out from the stainless steel mesh inside the tumbling piece 8, dispersing the coal powder from different angles, while making the coal powder rise and fall in the groove, effectively breaking the adsorption force and deposition state between the coal powder, so that more coal powder is carried by the hot air. This blowing powder assembly is designed ingeniously, the hot air conveying mode of the combination of the annular pipe 7 and the first air pipe 4, and the dynamic assistance of the tumbling piece 8 significantly improve the blowing efficiency. Compared with the traditional single-direction hot air powder carrying method, more coal powder can be timely separated from the grinding groove into the separation link, reducing the residue and accumulation of coal powder in the grinding groove, improving the grinding capacity 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 piece 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 refer to the attached Figure 2 , Figure 3 and Figure 5 , the second grinding assembly is installed above the mounting bracket 10, and the second grinding assembly includes a grinding block 16 fixedly connected to the top end of the mounting bracket 10. The top end of the first grinding groove 9 is fixedly connected with a rotating shaft 15, the top end of the rotating shaft 15 penetrates the feed pipe 2 and is fixedly connected with a grinding disc 21, the inside of the grinding block 16 is provided with a second grinding groove 23, the outer wall of the grinding disc 21 is attached to the surface of the second grinding groove 23, the top end of the grinding block 16 is fixedly connected with a separation cylinder 11, and the top end of the grinding disc 21 is fixedly connected with a taper seat 22.

[0035] Specifically, when the primary grinding groove 9 rotates under the power drive, the grinding disc 21 is synchronously rotated by the rotating shaft 15. The coal powder that does not meet the standard after the first grinding enters the separation cylinder 11 under the action of gravity and centrifugal force and is deposited between the grinding disc 21 and the secondary grinding groove 23. Due to the close fit and relative movement of the grinding disc 21 and the secondary grinding groove 23, the deposited coal powder is subjected to secondary extrusion and grinding, further refining 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, making it more evenly enter the secondary grinding area, improving the secondary grinding effect. The secondary grinding assembly realizes the automatic recovery and regrinding of the coarse coal powder, without the need for additional transfer and processing equipment, forming a coherent and efficient circulation system for the coal grinding process. Compared with the equipment without the secondary grinding function, the final qualified rate of the coal powder is greatly improved, the discharge and waste of unqualified coal powder are reduced, the utilization rate of coal resources is improved, and the wear and poor operation of the subsequent combustion equipment caused by the direct discharge of coarse coal powder are reduced, 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 , the flow guide assembly for separating coal powder, the flow guide assembly is installed on the inner wall of the top end of the shell 1, the flow guide assembly includes a plurality of guide vanes 19 rotatably connected to the top end of the separation cylinder 11, the top end of each guide vane 19 is fixedly connected with a straight gear 18, the inner wall of the top end of the shell 1 is rotatably connected with a shroud 12, the inner wall of the shroud 12 is fixedly connected with a straight gear ring 17, each straight gear 18 is meshingly connected with the straight gear ring 17, the outer wall of the straight gear 18 is provided with an adjusting assembly, the adjusting assembly includes a transmission frame 20 rotatably connected to the outer wall of the straight gear 18, the outer wall of the shell 1 is fixedly connected with an electric push rod 3, the driving end of the electric push rod 3 is rotatably connected to the end of the transmission frame 20.

[0037] Specifically, in the process of being blown up by hot air, the pulverized coal first passes through the guide vane 19, which can rotate within a certain range. The extension and retraction of the electric push rod 3 drive the transmission frame 20 to move, and then the straight gear 18 rotates along the straight tooth ring 17, realizing the angle adjustment of the guide vane 19. When the angle of the guide vane 19 changes, the centrifugal force experienced by the pulverized coal when passing through the guide vane 19 changes in size and direction. The standard coal is blown into the inside of the separation cover 13 under the action of appropriate centrifugal force, and the non-standard coal enters the separation cylinder 11 for secondary grinding under the action of larger centrifugal force. The guide vane assembly with adjustable angle enables the coal mill to adapt to different coal fineness requirements. During production, the angle of the guide vane 19 can be flexibly adjusted according to the combustion requirements of the boiler or the characteristics of different coal, and the separation effect of the pulverized coal can be accurately controlled. This not only improves the adaptability of the coal mill to various working conditions, reduces the problems of insufficient combustion and energy waste caused by unsuitable coal fineness, but also optimizes the operation 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 mill parts or adjustment of process parameters.

[0038] Please refer to the accompanying drawings Figure 1 、 Figure 2 and Figure 3 , the side wall of the shell 1 is fixedly connected with the feed pipe 2, the bottom end of the feed pipe 2 is located above the primary grinding groove 9, the top end of the shell 1 is fixedly connected with the separation cover 13, the separation cover 13 is set as a funnel-shaped structure with a narrow top and a wide bottom, and the top end of the separation cover 13 is used for being connected with a pulverized coal conveying pipeline.

[0039] Specifically, the raw coal falls into the primary grinding groove 9 for grinding treatment by gravity through the feed pipe 2. After the separation of the pulverized coal, the standard coal is blown to the separation cover 13. Since the separation cover 13 has a funnel-shaped structure with a narrow top and a wide bottom, the internal space gradually narrows, and the airflow speed gradually increases during the upward movement of the pulverized coal, which is beneficial to the rapid and concentrated guidance of the pulverized coal to the top end connected with the pulverized coal conveying pipeline, facilitating the efficient conveying of the qualified pulverized coal to the subsequent use link. The reasonable position of the feed pipe 2 ensures that the raw coal can accurately fall into the primary grinding groove 9 for grinding operation, avoiding problems such as uneven grinding or equipment jamming caused by feeding deviation. The special funnel-shaped design of the separation cover 13 effectively improves the output condition of the fine pulverized coal after separation. Compared with the traditional separation cover structure, it can reduce the turbulent flow of the pulverized coal in the cover, improve the collection and conveying efficiency of the pulverized coal, and make the qualified pulverized coal enter the pulverized coal conveying pipeline more quickly and stably, ensuring the timeliness and continuity of the pulverized coal supply, and providing strong support for the stable operation of the subsequent combustion equipment.

[0040] While embodiments of the application have been shown and described, it is to be understood that the embodiments described are merely exemplary of the principles and application of the present application. Numerous modifications and adaptions can be effected without departing from the spirit and scope of the present application, which is not limited to the exact construction and arrangement described. It is intended, therefore, to cover all modifications and adaptions that fall within the scope of the claims and their equivalents.

Claims

1. A high-efficiency pulverized coal separation device of a coal mill, characterized in that, The utility model relates to a coal grinding device, including: a base (6) for supporting the whole device, the top of the base (6) is fixedly connected with a shell (1), the inside of the shell (1) is installed with a mounting bracket (10) for installing the coal grinding roller, the top of the base (6) is installed with a primary grinding groove (9), the primary grinding groove (9) is used for grinding coal with the coal grinding roller, the side wall of the shell (1) is fixedly connected with a feeding pipe (2), the bottom of the feeding pipe (2) is located above the primary grinding groove (9); a powder blowing assembly, the powder blowing assembly 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 with a second air pipe (26), the end of the second air pipe (26) is fixedly connected with a ring pipe (7), a plurality of air holes are formed in the top of the ring pipe (7), the top of the second air pipe (26) is communicated with a first air pipe (4), the end of the first air pipe (4) is installed with a tumbling assembly; a secondary grinding assembly, the secondary grinding assembly is installed above the mounting bracket (10); a flow guide assembly for separating coal powder, the flow guide assembly is installed on the inner wall of the top of the shell (1); the tumbling assembly includes a connecting piece (24) rotatably connected to the end of the first air pipe (4), the first air pipe (4) is communicated with the connecting piece (24), the outer wall of the connecting piece (24) is fixedly connected with a bevel gear (25), the outer wall of the primary grinding groove (9) is fixedly connected with a bevel gear ring (14), the bevel gear (25) is meshingly connected with the bevel gear ring (14), the end of the connecting piece (24) is fixedly connected with a plurality of tumbling pieces (8), the inside of the tumbling piece (8) is provided with a stainless steel mesh; the tumbling pieces (8) are collectively formed as a spherical shape, and the tumbling pieces (8) are attached in the groove of the primary grinding groove (9).

2. A high-efficiency pulverized coal separating device of a coal mill according to claim 1, characterized in that, the secondary grinding assembly includes a grinding block (16) fixedly connected to the top of the mounting bracket (10), the top of the primary grinding groove (9) is fixedly connected with a rotating shaft (15) in the middle, the top of the rotating shaft (15) penetrates through the feeding pipe (2) and is fixedly connected with a grinding disc (21), the inside of the grinding block (16) is provided with a secondary grinding groove (23), the outer wall of the grinding disc (21) is attached to the surface of the secondary grinding groove (23), and the top of the grinding block (16) is fixedly connected with a separation cylinder (11).

3. A high-efficiency pulverized coal separating device of a coal mill according to claim 2, characterized in that, the top of the grinding disc (21) is fixedly connected with a taper seat (22).

4. A high-efficiency pulverized coal separating device of a coal mill according to claim 2, characterized in that, the flow guide assembly includes a plurality of flow guide pieces (19) rotatably connected to the top of the separation cylinder (11), the top of the flow guide piece (19) is fixedly connected with a spur gear (18), the inner wall of the top of the shell (1) is rotatably connected with a protective cover (12), the inner wall of the protective cover (12) is fixedly connected with a spur gear ring (17), the spur gear (18) is meshingly connected with the spur gear ring (17), and the outer wall of the spur gear (18) is installed with an adjusting assembly.

5. A high-efficiency pulverized coal separating device of a coal mill according to claim 4, characterized in that, the adjusting 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).

6. A high-efficiency pulverized coal separating device of a coal mill according to claim 1, characterized in that, The top end of the shell (1) is fixedly connected with a separation cover (13), the separation cover (13) is provided as a funnel shape with the top end being narrow and the bottom end being wide, and the top end of the separation cover (13) is used for being connected with a pulverized coal conveying pipeline.

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