Dust deposition prevention device for air volume measurement of coal mill

Abstract

The utility model relates to the technical field of dust deposition prevention devices, in particular to a dust deposition prevention device for measuring the air volume of a coal mill, which comprises an air measuring cylinder, a pulse dust cleaning mechanism, a dust deposition box, a positive hopper type dust blocking cover and a dust blocking mechanism, a wind measuring cavity is formed in the wind measuring cylinder, pulse dust cleaning mechanisms are arranged at the outer ends of the two sides of the wind measuring cylinder, a dust accumulation box is arranged below the wind measuring cylinder, a positive hopper type dust blocking cover is arranged at the front end of the wind measuring cylinder, a wind opening connecting flange is arranged at the front end of the positive hopper type dust blocking cover, a dust blocking mechanism is arranged at the rear end of the wind measuring cylinder, and a wind measuring connecting flange is arranged at the rear end of the dust blocking mechanism. According to the utility model, through the dual dust blocking effects of the positive hopper type dust blocking cover and the dust blocking mechanism, dust entering the wind measuring cavity is effectively reduced, the dust is prevented from blocking the wind measuring channel, and data acquired by measuring equipment is real and reliable, so that the accuracy of wind quantity measurement of the coal mill is improved; and accurate data support is provided for optimizing the combustion efficiency and improving the energy utilization rate.

Description

Technical Field

[0001] This utility model relates to the technical field of anti-ash accumulation devices, and in particular to an anti-ash accumulation device for measuring the air volume of a coal mill. Background Technology

[0002] A coal mill is a key piece of equipment that crushes and grinds coal into pulverized coal. It is widely used in industrial fields such as thermal power plants, cement plants, and metallurgical plants that require pulverized coal as fuel. Accurately measuring the air volume of a coal mill is of great significance for ensuring stable operation of the mill, optimizing combustion efficiency, and improving energy utilization.

[0003] In traditional coal mill airflow testing, the airflow probe is usually extended directly to the coal mill's seal for measurement. This can easily lead to dust-laden airflow entering the airflow measuring device. Furthermore, due to the lack of an effective dust-blocking structure, dust can easily clog the airflow measuring channel, resulting in distorted airflow measurement data and affecting the service life of the measuring equipment.

[0004] Therefore, in response to the problem that traditional coal mill airflow testing can easily lead to dust-laden airflow entering the measuring device and clogging the measuring channel, a coal mill airflow measurement anti-ash accumulation device can be designed. By installing an ash-blocking and ash-cleaning structure between the air outlet and the measuring device, the dust can be collected, thus solving the above problem. Utility Model Content

[0005] In order to overcome the shortcomings of traditional coal mill air volume testing, which easily leads to dust-laden airflow entering the air measurement device and clogging the air measurement channel, this utility model provides a coal mill air volume measurement anti-ash accumulation device.

[0006] The technical solution is as follows: A coal mill air volume measurement and anti-ash accumulation device includes an air measuring cylinder, a pulse cleaning mechanism, an ash collection box, a positive bucket-shaped ash blocking cover, and an ash blocking mechanism; the air measuring cylinder has an air measuring chamber for measuring the air volume of the coal mill, and pulse cleaning mechanisms for cleaning the air measuring chamber are provided at both outer ends of the air measuring cylinder. An ash collection box for collecting dust is provided at the bottom of the air measuring cylinder. A positive bucket-shaped ash blocking cover is provided at the front end of the air measuring cylinder to reduce dust from entering the air measuring chamber. An air outlet connecting flange for connecting the air outlet of the coal mill is provided at the front end of the positive bucket-shaped ash blocking cover. An ash blocking mechanism for preventing dust from entering the measuring equipment is provided at the rear end of the air measuring cylinder. An air measuring connection flange for connecting the testing equipment is provided at the rear end of the ash blocking mechanism.

[0007] Furthermore, multiple sets of pulse holes are opened through both sides of the wind measuring chamber, a dust removal port is opened at the bottom center of the wind measuring chamber, and buckles are provided at both ends of the bottom edge of the dust removal port. A dust collection groove is opened inside the dust collection box, and corresponding buckle strips are provided at both ends of the top edge of the dust collection box. An embedded connection groove is opened at the rear end of the wind measuring tube.

[0008] Furthermore, the inside of the hopper-shaped dust-blocking hood is provided with a hopper-shaped converging cavity, and the rear end of the wind measurement connecting flange is provided with a first connecting frame, and the front end of the hopper-shaped dust-blocking hood is engaged and connected with the first connecting frame.

[0009] Furthermore, a battery box is located on the top of the anemometer, and a battery pack is located inside the battery box. A digital display screen is located on the top of the battery box, and the digital display screen is electrically connected to the battery pack.

[0010] Furthermore, both sets of pulse cleaning mechanisms include pulse air pumps, which are located on both sides of the battery box. The pulse air pumps are electrically connected to the battery pack, and the air inlets of both sets of pulse air pumps are equipped with main air supply pipes.

[0011] Furthermore, the outer end of the main gas supply pipe is uniformly provided with multiple gas distribution pipes. One end of the gas distribution pipe is connected to the main gas supply pipe, and the other end of the gas distribution pipe extends into the interior of the pulse orifice. The other end of the gas distribution pipe is provided with a pulse nozzle.

[0012] Furthermore, the dust-blocking mechanism includes an inverted bucket-shaped dust-blocking hood, with an air measuring port at the center of the inverted bucket-shaped dust-blocking hood, and a second connecting frame at the rear end of the inverted bucket-shaped dust-blocking hood, the rear end of which is connected to the air measuring connecting flange.

[0013] Furthermore, the outer front end of the second connecting frame is provided with an outer connecting groove corresponding to the inner connecting groove, and the inner connecting groove and the outer connecting groove are matched and engaged.

[0014] The beneficial effects are that, compared to traditional coal mill airflow testing, which easily leads to dust-laden airflow entering the measuring device and clogging the measuring channel, this application effectively reduces dust entering the measuring chamber by using both positive and negative ash-blocking hoods. This prevents dust from clogging the measuring channel, ensuring the accuracy and reliability of the data obtained by the measuring equipment, thereby improving the accuracy of coal mill airflow measurement. This provides accurate data support for optimizing combustion efficiency and improving energy utilization. Reducing dust entry into the measuring equipment also reduces wear and damage caused by dust, effectively extending the service life of the measuring equipment and reducing equipment replacement and maintenance costs. The ash collection box is connected to the measuring cylinder by clips and strips, facilitating disassembly and installation while allowing workers to clean the dust inside the ash collection box in a timely manner. The pulse cleaning mechanism can perform comprehensive and efficient cleaning of the measuring chamber, reducing the difficulty and workload of maintenance and cleaning, and improving work efficiency. Attached Figure Description

[0015] Figure 1 This is a three-dimensional structural diagram of the coal mill air volume measurement and ash accumulation prevention device of this utility model;

[0016] Figure 2 This is a three-dimensional structural diagram of the combination of the wind measuring tube and the positive bucket-shaped dust blocking cover of this utility model;

[0017] Figure 3 This is a three-dimensional structural diagram of the combined anemometer and dust collection box of this utility model.

[0018] Figure 4 This is a three-dimensional structural diagram of the air outlet connecting flange and the first connecting frame of this utility model;

[0019] Figure 5 This is a three-dimensional structural diagram of the pulse cleaning mechanism of this utility model;

[0020] Figure 6 This is a three-dimensional structural diagram of the wind measuring connection flange and dust blocking mechanism of this utility model.

[0021] Explanation of reference numerals in the attached drawings: 1. Anemometer tube; 101. Anemometer chamber; 102. Dust removal port; 103. Pulse hole; 104. Embedded connecting groove; 2. Pulse dust removal mechanism; 201. Pulse air pump; 202. Main air supply pipe; 203. Distribution pipe; 204. Pulse nozzle; 3. Dust collection box; 301. Clip; 4. Upright bucket-shaped dust blocking cover; 401. Bucket-shaped collection chamber; 5. Air outlet connecting flange; 6. Dust blocking mechanism; 601. Second connecting frame; 602. Embedded connecting groove; 603. Inverted bucket-shaped dust blocking cover; 604. Anemometer port; 7. Anemometer connecting flange; 8. Battery box; 9. Battery pack; 10. Digital display screen; 11. Buckle; 12. First connecting frame. Detailed Implementation

[0022] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0023] A coal mill is a mechanical device specifically designed to grind lumpy or granular raw coal into fine powder. The particle size of the coal powder produced must meet the specific requirements of boiler combustion. Generally, the fineness of the coal powder needs to be controlled within a certain range. Typically, 70%-80% of the coal powder is required to pass through a 200-mesh sieve with a pore size of approximately 74 micrometers to ensure rapid and complete combustion in the boiler furnace.

[0024] The most common low-speed coal mill is the ball mill, which typically operates at 15-25 revolutions per minute. It mainly consists of a large cylindrical steel mill body, steel balls inside the cylinder, and a transmission device. During operation, the cylinder rotates slowly under the drive of an electric motor and a speed reducer. The steel balls inside the cylinder are lifted to a certain height and then fall, crushing the raw coal into coal powder through impact and grinding. The ball mill is highly adaptable to different types of coal and can grind coals of various hardness and volatile matter, but it has disadvantages such as high energy consumption, large footprint, and high noise.

[0025] Medium-speed coal mills typically operate at speeds between 50 and 300 rpm. Common types include bowl mills, medium-speed flat-pan mills, and E-type mills. These mills primarily pulverize raw coal through the squeezing and grinding action between the grinding rollers and the grinding disc. Taking a bowl mill as an example, after the raw coal enters the grinding bowl, it moves towards the edge under the rotation of the bowl. The grinding rollers, under the action of springs or hydraulic loading devices, squeeze and grind the coal. The coal powder is blown up by centrifugal force and hot air, and after passing through a separator, qualified coal powder is separated and enters the boiler. Unqualified coarse powder is returned to the grinding disc for further grinding. Medium-speed coal mills have advantages such as low energy consumption, small footprint, and simple pulverizing system, but their adaptability to different types of coal is relatively narrow, generally suitable for grinding bituminous coal and lean coal.

[0026] High-speed coal mills operate at speeds between 500 and 1500 rpm. A typical example is the fan-driven coal mill, which integrates coal grinding, drying, and conveying functions. Its working principle is similar to that of a fan. After the raw coal enters the mill, it is crushed by strong impacts and friction against the impact plates, guard plates, and other components under the drive of the high-speed rotating impeller. High-speed coal mills are characterized by their compact structure, large production capacity, and low power consumption. However, they suffer from severe wear and have high requirements for the moisture content of the coal. They are mainly suitable for grinding lignite with high moisture and high volatile matter content.

[0027] During coal mill operation, the airflow directly affects the mill's performance and boiler combustion efficiency. On one hand, the airflow must be sufficient to dry the raw coal thoroughly, reducing its moisture content to a level suitable for combustion. Insufficient airflow leads to inadequate drying, resulting in reduced mill output, difficulty in coal powder delivery, and even mill blockage. On the other hand, the airflow must deliver the pulverized coal to the boiler promptly and stably. Excessive airflow will coarsen the coal powder, affecting the stability and efficiency of boiler combustion and increasing the energy consumption of the pulverizing system. Insufficient airflow will cause coal powder to accumulate inside the mill, similarly affecting its normal operation. Therefore, accurately measuring the coal mill's airflow is crucial for ensuring safe and efficient operation, improving boiler combustion efficiency, and reducing power generation costs.

[0028] During the measurement process, the anemometer needs to be calibrated and maintained regularly to ensure the accuracy of the measurement data. For devices that are prone to clogging, such as Pitot tubes, the cleaning frequency should be increased. The temperature compensation and calibration parameters of the thermal anemometer should be checked regularly. When abnormal measurement data is found, the cause should be analyzed in time. It may be caused by factors such as anemometer malfunction, pipeline leakage, or changes in the operating conditions of the coal mill. For example, if the measured air volume suddenly drops, check whether the anemometer is blocked or whether there are any leaks or damages in the pipeline. At the same time, combine the operating parameters of the coal mill, such as the pressure difference between the inlet and outlet of the coal mill and the current, to comprehensively determine the problem and take appropriate measures.

[0029] Accurate measurement of air volume in low-speed coal mills is of great significance for ensuring the stable and efficient operation of coal mills and boilers. By rationally selecting air measurement methods and devices, scientifically installing and arranging them, and doing a good job in daily maintenance and troubleshooting, the accuracy and reliability of air measurement can be effectively improved, providing strong support for thermal power generation.

[0030] Example

[0031] like Figures 1-6 As shown, the coal mill air volume measurement and anti-ash accumulation device includes an air measuring cylinder 1, a pulse cleaning mechanism 2, an ash collection box 3, a positive bucket-shaped ash blocking cover 4, and an ash blocking mechanism 6. The air measuring cylinder 1 has an air measuring chamber 101 for measuring the air volume of the coal mill. Both outer ends of the air measuring cylinder 1 are equipped with pulse cleaning mechanisms 2 for cleaning the air measuring chamber 101. The bottom of the air measuring cylinder 1 is equipped with an ash collection box 3 for collecting dust. The front end of the air measuring cylinder 1 is equipped with a positive bucket-shaped ash blocking cover 4 to reduce dust from entering the air measuring chamber 101. The front end of the positive bucket-shaped ash blocking cover 4 is equipped with an air outlet connecting flange 5 for connecting to the coal mill air outlet. The rear end of the air measuring cylinder 1 is equipped with an ash blocking mechanism 6 to prevent dust from entering the measuring equipment. The rear end of the ash blocking mechanism 6 is equipped with an air measuring connection flange 7 for connecting to the testing equipment.

[0032] Multiple sets of pulse holes 103 are opened through both sides of the wind measuring chamber 101. A dust removal port 102 is opened at the bottom center of the wind measuring chamber 101. Buckles 11 are provided at both ends of the bottom of the dust removal port 102. A dust collection groove is opened inside the dust collection box 3. A corresponding clip 301 is provided at both ends of the top of the dust collection box 3. An embedded connecting groove 104 is opened at the rear end of the wind measuring tube 1. The dust collection box 3 is easily disassembled and installed through the cooperation of the buckles 11 and the clips 301, which makes it convenient for staff to clean the dust in the dust collection box 3 in a timely manner.

[0033] The inside of the positive bucket-shaped dust blocking cover 4 is provided with a bucket-shaped converging cavity 401. The rear end of the wind measuring connecting flange 7 is provided with a first connecting frame 12. The front end of the positive bucket-shaped dust blocking cover 4 is engaged with the first connecting frame 12. Through the bucket-shaped converging cavity 401 inside the positive bucket-shaped dust blocking cover 4, the airflow entering the wind measuring cylinder 1 can be initially guided and dust blocked, reducing the entry of large dust particles into the wind measuring cavity 101.

[0034] The top of the anemometer tube 1 is equipped with a battery box 8, inside which is a battery pack 9. The top of the battery box 8 is equipped with a digital display screen 10, which is electrically connected to the battery pack 9. Through the electrical connection between the digital display screen 10 on the top of the battery box 8 and the battery pack 9, the relevant parameters of the equipment can be displayed in real time, making it convenient for operators to intuitively understand the operating status of the equipment.

[0035] Both sets of pulse cleaning mechanisms 2 include a pulse air pump 201. The two sets of pulse air pumps 201 are located on both sides of the battery box 8. The pulse air pumps 201 are electrically connected to the battery pack 9. The air inlets of the two sets of pulse air pumps 201 are equipped with main air supply pipes 202. Through the setting of main air supply pipes 202 and distribution pipes 203, the gas is rationally distributed, and the gas generated by the pulse air pumps 201 is evenly delivered to each pulse nozzle 204.

[0036] The outer end of the main air supply pipe 202 is uniformly provided with multi-component air pipes 203. One end of the branch air pipe 203 is connected to the main air supply pipe 202, and the other end of the branch air pipe 203 extends into the interior of the pulse hole 103. The other end of the branch air pipe 203 is provided with a pulse nozzle 204. Through the multi-component air pipe 203 and the pulse nozzle 204, a comprehensive and efficient dust cleaning operation can be carried out on the inside of the air measuring chamber 101 to ensure that the dust in the air measuring chamber 101 is completely removed and to maintain a clean environment in the air measuring chamber 101.

[0037] The dust blocking mechanism 6 includes an inverted bucket-shaped dust blocking cover 603. The inverted bucket-shaped dust blocking cover 603 has a measuring port 604 at its center. The rear end of the inverted bucket-shaped dust blocking cover 603 has a second connecting frame 601. The rear end of the second connecting frame 601 is connected to the measuring flange 7. The measuring port 604 of the inverted bucket-shaped dust blocking cover 603 ensures that the probe of the measuring equipment can enter the measuring chamber 101 normally. At the same time, the inverted bucket-shaped structure can block dust in the airflow for a second time, further preventing dust from entering the measuring equipment, protecting the measuring equipment from dust damage, and extending the service life of the measuring equipment.

[0038] The outer front end of the second connecting frame 601 is provided with an outer connecting groove 602 corresponding to the inner connecting groove 104. The inner connecting groove 104 and the outer connecting groove 602 are matched and engaged. By combining the inner connecting groove 104 and the outer connecting groove 602, the dust blocking mechanism 6 is stably installed at the rear end of the wind measuring tube 1.

[0039] During operation, the workers first install and tighten the air outlet connecting flange 5 to the corresponding air outlet of the coal mill, ensuring a tight connection to prevent airflow leakage. Then, by combining the inner connecting groove 104 and the outer connecting groove 602, the ash blocking mechanism 6 is stably installed at the rear end of the air measuring cylinder 1. Finally, the air measuring connecting flange 7 is connected to the testing equipment, completing the installation of the entire device.

[0040] Next, check whether the dust collection box 3 is tightly connected to the bottom of the anemometer tube 1 by the buckle 11 and the clip 301, ensure that the battery pack 9 is installed in the battery box 8 and has sufficient power, and that the digital display screen 10 can display the dust cleaning data normally. At the same time, check whether the connection of each component of the pulse dust cleaning mechanism 2 is secure.

[0041] When conducting measurements, start the coal mill and, once it is running stably, turn on the testing equipment. After the test is completed, start the pulse cleaning mechanism 2 to clean the inside of the air measuring chamber 101 to ensure the cleanliness of the air measuring chamber 101. Then, depending on the running time of the coal mill and the amount of ash accumulation, periodically disassemble the ash collection box 3 for cleaning.

[0042] Its working principle is as follows: When the coal mill is running, the airflow carrying dust enters the upright bucket-shaped dust blocking hood 4 from the air inlet connecting flange 5. The bucket-shaped converging cavity 401 inside the hood initially guides the airflow. By utilizing the change in airflow direction and speed, large dust particles are deposited under the action of gravity, thereby blocking most of the dust from entering the measuring cylinder 1 and reducing the amount of dust in the measuring chamber 101. The airflow that has passed through the initial dust blocking enters the measuring chamber 101 of the measuring cylinder 1. The probe of the testing equipment enters the measuring chamber 101 through the measuring port 604 of the inverted bucket-shaped dust blocking hood 603 to measure the airflow and obtain accurate airflow data. The inverted bucket-shaped dust blocking hood 603 provides secondary blocking for the airflow entering the measuring chamber 101. Its special inverted bucket-shaped structure separates the dust in the airflow under the action of inertia and gravity, further preventing dust from entering the measuring equipment and protecting the measuring equipment.

[0043] When it is necessary to clean the air measuring chamber 101, the pulse air pump 201 is started. The pulse air pump 201 is electrically connected to the battery pack 9 and begins to work. The generated gas is evenly delivered to each pulse nozzle 204 through the main air supply pipe 202 and the multi-component air pipe 203. The pulse nozzle 204 sprays high-pressure gas into the air measuring chamber 101 to carry out a comprehensive and efficient cleaning operation, blowing off the dust attached to the inner wall of the air measuring chamber 101 and other components. The dust falls into the dust collection trough of the dust collection box 3 through the cleaning port 102 for collection.

[0044] Its beneficial effects are significant. Through the dual ash-blocking effect of the upright bucket-shaped ash-blocking cover 4 and the inverted bucket-shaped ash-blocking cover 603, it effectively reduces the amount of dust entering the air measuring chamber 101, avoids dust clogging the air measuring channel, and ensures that the data obtained by the measuring equipment is true and reliable. This improves the accuracy of coal mill air volume measurement, provides accurate data support for optimizing combustion efficiency and improving energy utilization, reduces dust entering the measuring equipment, reduces the wear and damage of dust to the measuring equipment, effectively extends the service life of the measuring equipment, and reduces equipment replacement and maintenance costs. The ash collection box 3 is connected to the air measuring cylinder 1 by the buckle 11 and the clip 301, which facilitates disassembly and installation. At the same time, the staff can clean the dust in the ash collection box 3 in a timely manner. The pulse cleaning mechanism 2 can perform comprehensive and efficient cleaning of the air measuring chamber 101, reducing the difficulty and workload of maintenance and cleaning for the staff and improving work efficiency.

Claims

1. A coal mill air volume measurement and ash accumulation prevention device, comprising an air volume measuring cylinder (1); characterized in that, It also includes a pulse cleaning mechanism (2), an ash collection box (3), a positive bucket-shaped ash blocking cover (4) and an ash blocking mechanism (6); the inside of the measuring cylinder (1) is provided with a measuring chamber (101) for measuring the air volume of the coal mill, and both outer ends of the measuring cylinder (1) are provided with a pulse cleaning mechanism (2) for cleaning the ash in the measuring chamber (101), the bottom of the measuring cylinder (1) is provided with an ash collection box (3) for collecting dust, the front end of the measuring cylinder (1) is provided with a positive bucket-shaped ash blocking cover (4) to reduce dust from entering the measuring chamber (101), the front end of the positive bucket-shaped ash blocking cover (4) is provided with an air outlet connecting flange (5) for connecting the air outlet of the coal mill, the rear end of the measuring cylinder (1) is provided with an ash blocking mechanism (6) to prevent dust from entering the measuring equipment, and the rear end of the ash blocking mechanism (6) is provided with a measuring connection flange (7) for connecting the testing equipment.

2. The coal mill air volume measurement and ash accumulation prevention device according to claim 1, characterized in that, Multiple sets of pulse holes (103) are opened through both sides of the wind measuring chamber (101). A dust removal port (102) is opened at the bottom center of the wind measuring chamber (101). A buckle (11) is provided at both ends of the bottom of the dust removal port (102). A dust collection groove is opened inside the dust collection box (3). A corresponding buckle strip (301) is provided at both ends of the top of the dust collection box (3). An embedded connecting groove (104) is opened at the rear end of the wind measuring tube (1).

3. The coal mill air volume measurement and ash accumulation prevention device according to claim 2, characterized in that, The inside of the positive bucket-shaped dust blocking cover (4) is provided with a bucket-shaped converging cavity (401), and the rear end of the wind measuring connecting flange (7) is provided with a first connecting frame (12). The front end of the positive bucket-shaped dust blocking cover (4) is engaged with the first connecting frame (12).

4. The coal mill air volume measurement and ash accumulation prevention device according to claim 1, characterized in that, The top of the anemometer tube (1) is equipped with a battery box (8), the inside of the battery box (8) is equipped with a battery pack (9), and the top of the battery box (8) is equipped with a digital display screen (10), which is electrically connected to the battery pack (9).

5. The coal mill air volume measurement and ash accumulation prevention device according to claim 4, characterized in that, Both sets of pulse cleaning mechanisms (2) include pulse air pumps (201). The two sets of pulse air pumps (201) are located on both sides of the battery box (8). The pulse air pumps (201) are electrically connected to the battery pack (9). The air inlets of the two sets of pulse air pumps (201) are equipped with main air supply pipes (202).

6. The coal mill air volume measurement and ash accumulation prevention device according to claim 5, characterized in that, The outer end of the main gas pipe (202) is uniformly provided with multiple component gas pipes (203). One end of the gas distribution pipe (203) is connected to the main gas pipe (202), and the other end of the gas distribution pipe (203) extends into the interior of the pulse hole (103). The other end of the gas distribution pipe (203) is provided with a pulse nozzle (204).

7. The coal mill air volume measurement and ash accumulation prevention device according to claim 2, characterized in that, The dust blocking mechanism (6) includes an inverted bucket-shaped dust blocking cover (603), with a wind measuring port (604) in the center of the inverted bucket-shaped dust blocking cover (603), and a second connecting frame (601) at the rear end of the inverted bucket-shaped dust blocking cover (603), the rear end of which is connected to the wind measuring connecting flange (7).

8. The coal mill air volume measurement and ash accumulation prevention device according to claim 7, characterized in that, The outer front end of the second connecting frame (601) is provided with an outer connecting groove (602) corresponding to the inner connecting groove (104), and the inner connecting groove (104) and the outer connecting groove (602) are matched and engaged.

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