Coal milling system of vertical mill

Abstract

The utility model discloses a vertical mill coal milling system, which comprises a raw coal bunker, a coal conveyor, a weighing and feeding mechanism and at least two bag-type dust removers, the raw coal bunker is arranged above the coal conveyor, the weighing and feeding mechanism is arranged below the coal conveyor, and the bag-type dust removers are arranged on the bag-type dust removers. Inlets of the at least two bag-type dust removers are connected to the weighing and feeding mechanism through pulverized coal feeding branch pipes, the vertical mill coal pulverizing system further comprises an auger conveyor and at least one pulverized coal bunker, the pulverized coal bunker is arranged below the auger conveyor, and the pulverized coal bunker is connected to the weighing and feeding mechanism through a pulverized coal feeding branch pipe. The auger conveyor is arranged below the at least two bag-type dust removers, and air outlets of the two bag-type dust removers are respectively provided with a negative pressure detection branch pipe. The device has the beneficial effects that large-batch steel mill pulverized coal can be produced, non-stop maintenance of the bag-type dust collector is realized, the production efficiency is improved, the temperature of a grinding cavity is guaranteed by utilizing a waste heat system, and energy is saved.

Description

Technical Field

[0001] This utility model relates to the field of coal powder production, and in particular to a vertical mill coal production system. Background Technology

[0002] Coal is widely used as a primary fuel in modern industrial production, with steel mills having a huge demand for it. Some processes require high combustion efficiency and pulverized coal as an additive. Therefore, coal is often ground into pulverized coal for use. Pulverized coal refers to coal with a particle size of less than 0.5 mm. During pulverization, raw coal is processed into particles with the required particle size and moisture content using a coal mill. To achieve the required moisture content, the coal mill needs to dry the gas, requiring a separate portion of coal as a heat source, thus increasing energy consumption. Furthermore, when pulverized coal is collected by a bag filter, if the bag filter becomes clogged or has low airflow after prolonged use, the production line needs to be shut down for maintenance, which also reduces production efficiency. Utility Model Content

[0003] The purpose of this invention is to provide a vertical mill coal production system in order to solve the above-mentioned problems.

[0004] This utility model achieves the above objectives through the following technical solutions:

[0005] A vertical mill coal production system includes a raw coal bunker, a coal conveyor, a weighing and feeding mechanism, and at least two bag filters;

[0006] The raw coal bunker is located above the coal conveyor, the weighing and feeding mechanism is located below the coal conveyor, and the inlets of at least two bag filters are connected to the weighing and feeding mechanism via powder feeding branch pipes.

[0007] The vertical mill coal preparation system also includes an auger conveyor and at least one pulverized coal silo, wherein the at least one pulverized coal silo is located below the auger conveyor, and the auger conveyor is located below at least two bag filters.

[0008] Negative pressure detection branch pipes are installed on the air outlets of both bag filters, and several of these negative pressure detection branch pipes are connected to a negative pressure pump via a negative pressure multi-port.

[0009] Furthermore, the weighing and feeding mechanism is connected to the heat source pump via a heat source pipe.

[0010] Furthermore, the negative pressure detection branch consists of a negative pressure air pipe and a control valve installed at one end of the negative pressure air pipe. The negative pressure air pipe is provided with a detection hole, and a pressure sensor is installed in the detection hole.

[0011] Furthermore, the coal conveyor consists of an outer shell and an inner conveyor belt assembly installed inside the outer shell. A coal inlet pipe is installed on the top of the outer shell, and a coal outlet pipe is installed on the bottom of the outer shell.

[0012] Furthermore, the weighing and feeding mechanism consists of a vertical mill and a rotor scale installed on top of the vertical mill.

[0013] Furthermore, the vertical mill coal preparation system also includes a controller and a coal feeding mechanism.

[0014] Furthermore, at least one conveying pipe is installed at the bottom of the auger conveyor.

[0015] The beneficial effects are as follows: the vertical mill coal production system described in this utility model can produce a large quantity of coal powder for steel plants, realize non-stop maintenance of bag filter dust collectors, improve production efficiency, and utilize waste heat system to ensure the temperature of grinding chamber, thus saving energy. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the system structure of a vertical mill coal preparation system described in this utility model;

[0017] Figure 2 This is an enlarged schematic diagram of the coal conveyor of a vertical mill coal preparation system described in this utility model;

[0018] Figure 3 This is a schematic diagram showing the connection relationship between the negative pressure detection branch pipe and the negative pressure multi-port in a vertical mill coal preparation system described in this utility model.

[0019] The annotations in the attached figures are explained as follows:

[0020] 1. Raw coal bunker; 2. Coal conveyor, 21. Outer shell, 22. Inner conveyor belt assembly, 23. Coal inlet pipe, 24. Coal outlet pipe; 3. Weighing and feeding mechanism, 31. Rotary scale, 32. Vertical mill; 4. Powder feeding branch pipe; 5. Bag filter dust collector; 6. Negative pressure detection branch pipe, 61. Negative pressure air pipe, 62. Air pressure sensor, 63. Control valve; 7. Negative pressure multi-port; 8. Feeding pipe multi-port; 9. Negative pressure pump; 10. Controller; 11. Screw conveyor; 12. Conveying pipe; 13. Powdered coal bunker; 14. Heat source pipe; 15. Heat source pump; 16. Coal feeding mechanism. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this utility model, but not all embodiments.

[0022] The following is combined Figures 1 to 3The vertical mill coal preparation system provided in this embodiment will be further described as follows:

[0023] Please refer to Figure 1 The present invention provides a vertical mill coal production system, including a raw coal bunker 1, a coal conveyor 2, a weighing and feeding mechanism 3, and at least two bag filters 5. The raw coal bunker 1 is located above the coal conveyor 2, the weighing and feeding mechanism 3 is located below the coal conveyor 2, and the inlets of the at least two bag filters 5 are connected to the weighing and feeding mechanism 3 through powder feeding branch pipes 4.

[0024] The phrase "at least two" includes two or more cases, and in order to ensure that the parameters of each bag filter 5 are similar, each bag filter 5 is set on the same plane.

[0025] The vertical mill coal preparation system also includes an auger conveyor 11 and at least one pulverized coal bin 13. The number of pulverized coal bins 13 is set according to requirements and they are arranged in a single row. At least one pulverized coal bin 13 is located below the auger conveyor 11, and the auger conveyor 11 is located below at least two bag filters 5.

[0026] In this embodiment, the raw coal in the raw coal bunker 1 falls into the coal conveyor 2 and is directly fed into the weighing and feeding mechanism 3. The weighing and feeding mechanism 3 grinds the raw coal and weighs it, and then sends the powder into at least two bag filters 5 for powder-gas separation via pneumatic conveying. The coal powder filtered in the bag filters 5 falls into the screw conveyor 11 and is discharged into the coal powder bunker 13. The screw conveyor 11 is provided with at least one discharge port, the number of which matches the number of coal powder bunkers 13.

[0027] At least one negative pressure detection branch pipe 6 is installed on the air outlet of the bag filter 5. Several negative pressure detection branch pipes 6 are connected to a negative pressure pump 9 through a negative pressure multi-port 7. The negative pressure detection branch pipe 6 is used to detect the air pressure inside the pipe. If the pressure is too low, it indicates that there is a blockage in the matching bag filter 5. The valve can be closed for maintenance.

[0028] like Figures 1-3 As shown, embodiments of this utility model also disclose the following more optimized specific structures:

[0029] The vertical mill coal preparation system also includes a heat source pump 15, which is connected to the weighing and feeding mechanism 3 via a heat source pipe 14. In this embodiment, the heat source pump 15 uses the waste heat system of the steel plant to recover heat source for heating to ensure the temperature inside the weighing and feeding mechanism 3. The temperature inside the heat source pipe 14 is 180-220 degrees Celsius, and the flow rate is 300,000 cubic meters per hour.

[0030] The vertical mill coal preparation system also includes a coal feeding mechanism 16. In this embodiment, the coal feeding mechanism 16 adopts a conveyor belt structure. According to the conveying direction, the end of the coal feeding mechanism 16 is set above the raw coal bunker 1 to introduce raw coal into the raw coal bunker 1.

[0031] The negative pressure detection branch pipe 6 consists of a negative pressure air pipe 61 and a control valve 63 installed at one end of the negative pressure air pipe 61. The negative pressure air pipe 61 is provided with a detection hole, and a pressure sensor 62 is installed in the detection hole and sealed. The pressure sensor 62 detects the internal pressure of the negative pressure air pipe 61. When the pressure is less than the threshold, it indicates that the corresponding bag filter 5 is blocked and needs to be cleaned and repaired in time. Closing any bag filter 5 will not affect the operation of the vertical mill coal preparation system.

[0032] The coal conveyor 2 consists of a housing 21 and an inner conveyor belt assembly 22 installed inside the housing 21. A coal inlet pipe 23 is installed on the top of the housing 21, and a coal outlet pipe 24 is installed on the bottom of the housing 21. The coal outlet pipe 24 is located below the conveying end of the inner conveyor belt assembly 22. The coal conveyor 2 is connected to the feed port of the weighing and feeding mechanism 3 through the coal outlet pipe 24. The coal conveyor 2 is connected to the bottom of the raw coal bunker 1 through the coal inlet pipe 23.

[0033] The weighing and feeding mechanism 3 consists of a vertical mill 32 and a rotor scale 31 installed on top of the vertical mill 32. The vertical mill 32 is an HRM series vertical mill, which is often used in conjunction with the rotor scale 31 to facilitate the grinding and metering of coal powder. A feed pipe multi-port 8 is installed on the discharge port of the rotor scale 31, which is used for the installation of the powder feeding branch pipe 4.

[0034] The vertical mill coal preparation system also includes a controller 10, which is controlled by a PLC control system. It can control each of the above components individually and can also receive various feedback signals, such as the metering signal of the rotor scale 31 and the air pressure signal of the air pressure sensor 62, thereby initiating corresponding commands for control, such as closing the control valve 63 when the air pressure sensor 62 is below the threshold.

[0035] The auger conveyor 11 consists of a transverse conveying cylinder shell and an auger disposed inside the conveying cylinder shell. The auger is driven by an outer auger motor, thereby driving the coal powder to rotate. At least one conveying pipe 12 is installed at the bottom of the auger conveyor 11. The number of conveying pipes 12 matches the number of coal powder bins 13. The end of the conveying pipe 12 extends into the matching coal powder bin 13. The bottom pipes of at least two bag filters 5 are connected to the auger conveyor 11.

[0036] like Figures 1-3The vertical mill coal production system shown is mainly used for large-scale coal pulverization of raw coal in steel plants. The raw coal silo 1 can store 300 tons of coal. The raw coal is sent to the weighing and feeding mechanism 3 through the coal conveyor 2 below. The heat source of the weighing and feeding mechanism 3 is mainly provided by the waste heat recovery system of the steelmaking process in the steel plant. The coal is sent to the HRM series vertical mill for grinding through the heat source pump 15. After being weighed by the rotor scale 31, it is pneumatically fed into at least two bag dust collectors 5. The filtered coal powder is then transported to each coal powder silo 13 through the screw conveyor 11 for use.

[0037] The vertical mill coal production system can produce large quantities of pulverized coal used in steel plants, with a large capacity. It is equipped with at least two bag filters 5, and the pulverized coal filtration status is monitored in real time through negative pressure monitoring inside the pipes. Clogged bag filters are repaired in time, and the system continues to operate normally during maintenance to ensure its production efficiency. The waste heat from the combustion of pulverized coal in the steel plant is reused to ensure the grinding temperature and save energy.

[0038] Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of this utility model as claimed.

Claims

1. A vertical mill coal preparation system, characterized in that: Includes raw coal bunker (1), coal conveyor (2), weighing and feeding mechanism (3), and at least two bag filters (5); The raw coal bunker (1) is located above the coal conveyor (2), the weighing and feeding mechanism (3) is located below the coal conveyor (2), and the inlets of at least two bag dust collectors (5) are connected to the weighing and feeding mechanism (3) through powder feeding branch pipes (4). The vertical mill coal preparation system also includes an auger conveyor (11) and at least one pulverized coal bin (13), the at least one pulverized coal bin (13) being located below the auger conveyor (11), the auger conveyor (11) being located below at least two bag filters (5); Negative pressure detection branch pipes (6) are installed on the air outlets of the two bag dust collectors (5), and several of the negative pressure detection branch pipes (6) are connected to a negative pressure pump (9) through a negative pressure multi-port (7).

2. The vertical mill coal preparation system according to claim 1, characterized in that: The weighing and feeding mechanism (3) is connected to a heat source pump (15) via a heat source pipe (14).

3. The vertical mill coal preparation system according to claim 1, characterized in that: The negative pressure detection branch pipe (6) consists of a negative pressure air pipe (61) and a control valve (63) installed on one end of the negative pressure air pipe (61). The negative pressure air pipe (61) is provided with a detection hole, and a pressure sensor (62) is installed in the detection hole.

4. The vertical mill coal preparation system according to claim 1, characterized in that: The coal conveyor (2) consists of an outer shell (21) and an inner conveyor belt assembly (22) installed inside the outer shell (21). A coal inlet pipe (23) is installed on the top of the outer shell (21), and a coal outlet pipe (24) is installed on the bottom of the outer shell (21).

5. A vertical mill coal preparation system according to claim 1, characterized in that: The weighing and feeding mechanism (3) consists of a vertical mill (32) and a rotor scale (31) installed on top of the vertical mill (32).

6. A vertical mill coal preparation system according to claim 1, characterized in that: The vertical mill coal preparation system also includes a controller (10) and a coal feeding mechanism (16).

7. A vertical mill coal preparation system according to claim 1, characterized in that: At least one conveying pipe (12) is installed at the bottom of the auger conveyor (11).

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