Flushing device for drum screen at outlet of coal mill

Abstract

The utility model relates to the technical field of drum screen cleaning, in particular to a washing device for a drum screen at an outlet of a coal mill, which comprises a drum screen and a gas-water spraying device, the drum screen comprises a screen drum and a drum shield, the screen drum is arranged on the inner side of the drum shield, and the gas-water spraying device comprises a spraying pipe and a gas-water mixer. A spraying pipe is arranged on the inner side of the upper portion of the roller protective cover, and a gas-water conveying pipeline is fixedly communicated between a right inlet of the spraying pipe and an outlet of the gas-water mixer. The device is reasonable and compact in structure and convenient to use, by additionally arranging the air-water spraying device, instrument air and water are mixed according to a specific proportion, impurities blocking sieve holes in the sieve barrel can be effectively removed, the sieve holes are kept unblocked, the concentration of coal slurry can be controlled and can be improved by 0.5%, the production process is stabilized, economic benefits are increased, and the device is suitable for popularization and application. The fluctuation of the whole process system caused by the quality of the coal slurry and the waste of raw water caused by excessive flushing are avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of drum screen cleaning, in particular to a drum screen washing device used for a coal mill outlet. Background Art

[0002] The drum screen of the coal mill is a screening and separation device. The coal slurry discharged from the coal mill is filtered through the drum screen. After the drum screen filters the coal slurry, the coal powder particles with qualified particle size enter the discharge trough through the sieve holes of the screen, and the large particles of coal powder with unqualified particle size enter the carriage for collecting large particles of coal powder through the cyclone channel of the drum screen. However, due to the wide variety of coal types and variable ratios, the concentration fluctuation of coal slurry becomes difficult to control. This not only increases the difficulty of mill operation, but also leads to frequent blockage of the drum screen holes, an increase in large particles, and even overflow of the drum screen. Summary of the invention

[0003] The utility model provides a washing device for a drum screen at a coal mill outlet, which overcomes the above-mentioned shortcomings of the prior art and can effectively solve the problem of sieve hole blockage in the drum screen at the outlet of the existing coal mill.

[0004] The technical scheme of the utility model is realized through the following measures: a device for washing a drum screen at a coal mill outlet comprises a drum screen and an air-water spraying device, the drum screen comprises a screen cylinder and a drum shield, the screen cylinder is arranged inside the drum shield, the air-water spraying device comprises a spraying pipe and an air-water mixer, a spraying pipe is arranged inside the upper part of the drum shield, an air-water conveying pipeline is fixedly connected between the right inlet of the spraying pipe and the outlet of the air-water mixer, and the inlet of the air-water mixer is respectively fixedly connected with an instrument air supply pipeline and a primary water inlet pipeline.

[0005] The following are further optimizations and / or improvements to the above utility model technical solution:

[0006] The above-mentioned air and water spray device also includes an electrical distribution cabinet and a time relay. Solenoid valves are respectively provided on the instrument air supply pipeline and the primary water inlet pipeline. The solenoid valves on the instrument air supply pipeline and the primary water inlet pipeline are respectively connected to the normally open contacts of the time relay, and the time relay is electrically connected to the electrical distribution cabinet.

[0007] The above-mentioned air and water spray device also includes a spray guard plate. Fixing holes are opened on the left and right sides of the upper part of the drum guard. The spray pipe is fixed on the drum guard through the fixing holes. A spray hole inclined downward is provided on the front side of the spray pipe. A spray guard plate is fixedly installed on the drum guard on the front side of the spray pipe.

[0008] The spray guard plate is in an inclined shape with the front lower and the back higher, and the lower end of the spray guard plate is located below the spray pipe.

[0009] The diameter of the spray hole is between 2 mm and 5 mm.

[0010] Manual valves are also fixedly installed on the instrument air pipeline and the primary water inlet pipeline below the solenoid valve.

[0011] The utility model has a reasonable and compact structure and is easy to use. By adding an air-water spray device, the instrument air and water are mixed in a specific proportion, which can effectively remove impurities clogging the sieve holes on the sieve cylinder, keep the sieve holes unobstructed, and help control the concentration of the coal slurry. The coal slurry concentration can be increased by 0.5%, stabilize the production process, increase economic benefits, and avoid fluctuations in the entire process system caused by the quality of the coal slurry and waste of raw water caused by excessive flushing. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Attached Figure 1 It is a schematic diagram of the main structure of the utility model.

[0013] Attached Figure 2 It is a schematic diagram of the right view structure of the drum screen.

[0014] Attached Figure 1 The codes are: 1 for screen cylinder, 2 for drum guard, 3 for spray pipe, 4 for air-water mixer, 5 for air-water transmission pipeline, 6 for instrument air supply pipeline, 7 for primary water inlet pipeline, 8 for spray guard plate, 9 for manual valve, 10 for spray hole, 11 for electrical distribution cabinet, 12 for time relay, and 13 for solenoid valve. DETAILED DESCRIPTION

[0015] The present invention is not limited by the following embodiments, and specific implementation methods can be determined according to the technical solution of the present invention and actual conditions.

[0016] In the present invention, unless otherwise specified, the equipment and devices used are all the equipment and devices known and used in the art. For example, the electrical distribution cabinet and the time relay can be the equipment known and used in the art.

[0017] In the present invention, for the convenience of description, the relative position relationship of each component is described according to the attached manual. Figure 1 The layout is described in detail, such as the positional relationship of front, back, top, bottom, left, right, etc., which is based on the attached manual. Figure 1 It is determined by the layout direction.

[0018] The present invention is further described below in conjunction with the embodiments and drawings:

[0019] Embodiment 1: As attached Figure 1 , 2As shown, the device for washing the drum screen at the outlet of the coal mill comprises a drum screen and an air-water spraying device, the drum screen comprises a screen cylinder 1 and a drum shield 2, the screen cylinder 1 is arranged on the inner side of the drum shield 2, the air-water spraying device comprises a spray pipe 3 and an air-water mixer 4, a spray pipe 3 is arranged on the inner side of the upper part of the drum shield 2, an air-water conveying pipeline 5 is fixedly connected between the right inlet of the spray pipe 3 and the outlet of the air-water mixer 4, and the inlet of the air-water mixer 4 is respectively fixedly connected to an instrument air supply pipeline 6 and a primary water inlet pipeline 7.

[0020] During use, the device sends instrument air and primary water to the gas-water mixer 4 in a specific ratio. After the gas and water are mixed by the gas-water mixer 4, the mesh holes on the screen cylinder 1 are sprayed and cleaned through the spray pipe 3, which can effectively remove impurities blocking the mesh holes on the screen cylinder 1 and keep the mesh holes unobstructed, which helps to control the concentration of the coal slurry. The concentration of the coal slurry can be increased by 0.5%, stabilize the production process, increase economic benefits, and avoid fluctuations in the entire process system caused by the quality of the coal slurry and waste of raw water caused by excessive flushing. According to needs, the gas-water mixer 4 uses a 4-inch buffer tank to help stabilize the pressure of the mixed gas and ensure the stability of the spraying process.

[0021] According to actual needs, the above-mentioned drum screen washing device for coal mill outlet can be further optimized and / or improved:

[0022] Embodiment 2: It is different from Embodiment 1 in that: Figure 1 , 2 As shown, the air-water spray device also includes an electrical distribution cabinet 11 and a time relay 12. Electromagnetic valves 13 are respectively provided on the instrument air supply pipeline 6 and the primary water inlet pipeline 7. The electromagnetic valves 13 on the instrument air supply pipeline 6 and the primary water inlet pipeline 7 are respectively connected to the normally open contacts of the time relay 12, and the time relay 12 is electrically connected to the electrical distribution cabinet 11.

[0023] During use, the time relay 12 is set with a flushing time and a flushing interval time setting value. When the preset flushing time and flushing interval time setting value is reached, the normally open contact of the time relay 12 is closed, and the solenoid valve 13 is opened to time the solenoid valve 13. Such a setting, by setting the flushing time and flushing interval time in the time relay 12, mixing the instrument air and water in a specific ratio within a certain period of time, and using the mixed air and water to automatically flush the drum screen, not only reduces the burden on the staff, improves work efficiency and reduces human errors, but also eliminates the need for operators to frequently go back and forth to the site for manual flushing operations, effectively avoiding system fluctuations caused by coal slurry quality and waste of raw water caused by excessive flushing.

[0024] Compared with manual flushing, this device uses the time relay 12 to time the solenoid valve 13, and through precise time setting, ensures that the solenoid valve 13 is opened or closed at a specific time, thereby controlling the spraying time to achieve automatic flushing, which has higher efficiency and more stable flushing effect. It can ensure that the drum screen gets the right amount of flushing water within the specified time, and will not be blocked due to insufficient flushing, nor will it waste water resources due to excessive flushing, thereby improving the operating efficiency of the entire coal slurry preparation system, and is also conducive to saving energy and protecting the environment. More importantly, the automatic flushing method reduces the workload of operators.

[0025] Embodiment 3: It differs from Embodiment 1 to Embodiment 2 in that: Figure 1 , 2 As shown, the air-water spraying device further includes a spray guard plate 9, fixing holes are provided on the left and right sides of the upper part of the drum guard 2, the spray pipe 3 is fixed on the drum guard 2 through the fixing holes, a spray hole 10 inclined downward is provided on the front side of the spray pipe 3, and a spray guard plate 9 is fixedly installed on the drum guard 2 on the front side of the spray pipe 3. During use, the spray guard plate 9 is provided to prevent the coal slurry in the screen drum 1 from being thrown onto the spray pipe 3 and blocking the spray hole 10 during the rotation of the screen drum 1.

[0026] According to the requirements, the rotation direction of the screen drum 1 is clockwise in its right view, so that the spray direction of the spray hole 10 is opposite to the rotation angle of the drum screen, so as to better contact and remove large particles on the screen of the drum screen, and this reverse force can increase the effective filtering area of ​​the drum screen, thereby improving the screening efficiency.

[0027] Embodiment 4: It differs from Embodiments 1 to 3 in that: Figure 1 , 2 As shown, the spray guard plate 9 is in an inclined shape with a lower front and a higher rear, and the lower end of the spray guard plate 9 is located below the spray pipe 3. During use, the inclined spray guard plate 9 is provided to prevent the blocked coal slurry from accumulating on its front side.

[0028] Embodiment 5: It differs from Embodiments 1 to 4 in that: Figure 1 , 2 As shown, the diameter of the spray hole 10 is between 2 mm and 5 mm. During use, such a setting can make the spray water spray better to the outside of the screen of the screen cylinder 1, ensuring that the screen of the screen cylinder 1 is thoroughly cleaned, and in order to maintain the nozzle pressure and atomization effect of the spray pipe 3, the diameter and number of the spray holes 10 can be adjusted according to the specific size and mesh number of the screen cylinder 1, thereby ensuring the uniform distribution of the water mist and improving the cleaning effect.

[0029] Embodiment 6: It differs from Embodiments 1 to 5 in that: Figure 1 , 2As shown, manual valves 9 are fixedly installed on the instrument air pipeline and the primary water inlet pipeline 7 below the solenoid valve 13. During use, the operator selects the optimal supply of instrument air and water by adjusting the opening of the manual valve 9.

[0030] The above technical features constitute the embodiments of the present utility model, which have strong adaptability and implementation effect. Non-essential technical features can be added or reduced according to actual needs to meet the requirements of different situations.

[0031] The use process of the embodiment of the utility model is as follows: first, the opening and closing of the solenoid valve 13 is controlled by the time relay 12, and the instrument air and primary water are respectively sent to the air-water mixer 4 through the instrument air supply pipeline 6 and the primary water inlet pipeline 7 for mixing, and then the mixed air and water are sprayed to the sieve holes on the screen cylinder 1 through the spray holes 10 on the spray guard plate 9 to remove impurities in the sieve holes and keep the sieve holes unobstructed.

Claims

1. A device for washing drum screen at coal mill outlet, characterized in that It includes a drum screen and an air-water spray device. The drum screen includes a screen cylinder and a drum shield. The screen cylinder is arranged on the inner side of the drum shield. The air-water spray device includes a spray pipe and an air-water mixer. A spray pipe is arranged on the inner side of the upper part of the drum shield. An air-water transmission pipeline is fixedly connected between the right inlet of the spray pipe and the outlet of the air-water mixer. The inlet of the air-water mixer is respectively fixedly connected with an instrument air supply pipeline and a primary water inlet pipeline.

2. The device for washing the drum screen at the outlet of a coal mill according to claim 1, characterized in that The air-water spray device also includes an electrical distribution cabinet and a time relay. The instrument air supply pipeline and the primary water inlet pipeline are respectively provided with solenoid valves. The solenoid valves on the instrument air supply pipeline and the primary water inlet pipeline are respectively connected to the normally open contacts of the time relay, and the time relay is electrically connected to the electrical distribution cabinet.

3. The device for washing the outlet drum screen of a coal mill according to claim 1 or 2, characterized in that The air-water spray device also includes a spray guard plate. Fixed holes are opened on the left and right sides of the upper part of the drum guard. The spray pipe is fixed on the drum guard through the fixed holes. A spray hole inclined downward is provided on the front side of the spray pipe. A spray guard plate is fixedly installed on the drum guard on the front side of the spray pipe.

4. The device for washing the drum screen at the outlet of a coal mill according to claim 3, characterized in that The spray guard plate is inclined with the front lower and the back higher, and the lower end of the spray guard plate is located below the spray pipe.

5. The device for washing the drum screen at the outlet of a coal mill according to claim 3, characterized in that The diameter of the spray hole is between 2mm and 5mm.

6. The device for washing the drum screen at the outlet of a coal mill according to claim 4, characterized in that The diameter of the spray hole is between 2mm and 5mm.

7. The device for washing the drum screen at the outlet of a coal mill according to claim 1, 2, 4, 5 or 6, characterized in that Manual valves are also fixedly installed on the instrument air pipeline and the primary water inlet pipeline below the solenoid valve.

8. The device for washing the drum screen at the outlet of a coal mill according to claim 3, characterized in that Manual valves are also fixedly installed on the instrument air pipeline and the primary water inlet pipeline below the solenoid valve.

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