Coal mill air volume measuring instrument reverse blowing device

Abstract

The utility model provides a coal mill air volume measuring instrument reverse blowing device, and relates to the technical field of chemical engineering devices.The coal mill air volume measuring instrument reverse blowing device is characterized in that the top of a Venturi measuring tube assembly is communicated with the interior of a dust-containing airflow cabin assembly, and the bottom of the Venturi measuring tube assembly is communicated with the bottom of the dust-containing airflow cabin assembly; a feeding port of the anti-blocking assembly is communicated with the bottom of the Venturi measuring tube assembly, an outlet of the anti-blocking assembly is communicated with a top inlet of the Venturi measuring tube assembly through a guide pipe, the sedimentation assembly is arranged at the bottom of an inlet of the anti-blocking assembly, and an outlet of the sedimentation assembly is communicated with a bottom outlet of the dust-containing airflow cabin assembly. According to the device, clean gas is purified through multiple times of dust isolation, dust of the coal mill is effectively prevented from entering an overall circulation system through the differential pressure transmitter, then blockage of the vertical guide pipe and the differential pressure transmitter is avoided, the daily maintenance workload is reduced, the blowing frequency is reduced, and the service life of the coal mill is prolonged. And the service life of the differential pressure transmitter is prolonged.

Description

Technical Field

[0001] This application relates to the field of chemical plant technology, and more specifically, to a backflushing device for measuring air volume in a coal mill. Background Technology

[0002] A coal mill is a machine that crushes and grinds coal into pulverized coal; it is an important auxiliary equipment for pulverized coal boilers. The coal grinding process mainly involves three methods: crushing, impact crushing, and grinding. Crushing consumes the least energy, while grinding consumes the most. Various coal mills employ two or all three methods in their pulverizing process, but the dominant method depends on the type of mill. The air volume of the coal mill is measured using an insertion-type multi-point Venturi measuring device, which is led to a differential pressure transmitter via a pressure-conducting pipe. The differential pressure transmitter sends the differential pressure signal to the DCS (Distributed Control System), where it is calculated and displayed.

[0003] The pressure guide pipes and transmitter diaphragms of existing coal mill airflow measuring instruments are clogged by dust, resulting in heavy daily maintenance and frequent purging. However, purging can easily damage the transmitter diaphragm, reducing instrument lifespan and increasing investment, thus presenting shortcomings. Utility Model Content

[0004] To overcome the above shortcomings, this utility model provides a back-purging device for coal mill airflow measuring instruments. It aims to improve the existing coal mill airflow measuring instruments where dust ingress causes blockages in the pressure guide pipes and transmitter diaphragms, resulting in heavy daily maintenance workload and frequent purging. Furthermore, purging can easily damage the transmitter diaphragm, reducing instrument lifespan and increasing investment costs.

[0005] This application is implemented as follows:

[0006] This application provides a backflushing device for measuring the air volume of a coal mill, including:

[0007] A dust-laden airflow chamber assembly, which is connected to the coal mill;

[0008] A Venturi measuring tube assembly, wherein the top of the Venturi measuring tube assembly is connected to the interior of the dust-laden airflow chamber assembly, and the bottom of the Venturi measuring tube assembly is connected to the bottom of the dust-laden airflow chamber assembly;

[0009] An anti-clogging component is provided on one side of the dust-laden airflow chamber assembly. The inlet of the anti-clogging component is connected to the bottom of the Venturi measuring tube assembly, and the outlet of the anti-clogging component is connected to the top inlet of the Venturi measuring tube assembly via a conduit.

[0010] A settling component is provided at the bottom of the inlet of the anti-clogging component, and the outlet of the settling component is connected to the bottom outlet of the dust-laden airflow chamber component.

[0011] In one embodiment of this application, the dust-laden airflow chamber assembly includes a main chamber, a platform, and a conical guide chamber. The main chamber is divided into an upper section and a lower section. The platform is fixedly connected to the bottom of the upper section of the main chamber and is disposed at the top of the lower section of the main chamber. The top of the conical guide chamber is connected to the bottom of the lower section of the main chamber.

[0012] In one embodiment of this application, a main discharge valve is installed at the outlet of the conical guide hopper.

[0013] In one embodiment of this application, both the inner wall of the main cabin and the inner wall of the conical guide chamber are provided with a wear-resistant ceramic layer.

[0014] In one embodiment of this application, the Venturi measuring tube assembly includes a vertical guide tube, a differential pressure transmitter, and a one-way control valve. The side wall of the vertical guide tube is connected to two connecting pipes arranged vertically, which are respectively connected to the interior of the dust-laden airflow chamber assembly. The differential pressure transmitter is connected to the top of the vertical guide tube, and the one-way control valve is located in the middle of the vertical guide tube.

[0015] In one embodiment of this application, the bottom of the vertical guide tube is connected to a thickened nozzle, which extends into the interior of the inlet of the anti-clogging component.

[0016] In one embodiment of this application, the anti-clogging component includes a horn-shaped collecting port, a V-shaped guide plate, a connecting conduit, a root gate valve, a thickened conduit, a thickened dustproof perforated plate, a segmented dustproof cotton layer, and an interval discharge pipe. The inner end of the horn-shaped collecting port is connected to the front end of the connecting conduit. The V-shaped guide plate is fixedly installed at the inner bottom of the horn-shaped collecting port, and the inclination angle of the V-shaped guide plate is set to 30-45 degrees. The V-shaped guide plate is matched with the outlet of the Venturi measuring tube assembly. The root gate valve is installed at the upper part of the connecting conduit. The thickened conduit is connected to the tail end of the connecting conduit. The thickened dustproof perforated plate is fixedly installed inside the horn-shaped collecting port. The segmented dustproof cotton layer is fixedly installed inside the connecting conduit. The top of the interval discharge pipe is connected to the inner front end of the connecting conduit. The inlet of the interval discharge pipe is located in the middle of the thickened dustproof perforated plate and the segmented dustproof cotton layer. The bottom of the outlet of the interval discharge pipe is connected to the side wall of the settling component.

[0017] In one embodiment of this application, the holes on the thickened dustproof perforated plate are arranged obliquely upward, and the inclination angle of the holes on the thickened dustproof perforated plate is set to 30 degrees-45 degrees.

[0018] In one embodiment of this application, the segmented dustproof cotton layer is configured as two segments, and the segmented dustproof cotton layer is disposed on both sides of the root gate valve.

[0019] In one embodiment of this application, the settling assembly includes a settling chamber and a settling conduit. The settling chamber is fixedly connected to the inlet of the anti-clogging assembly and is disposed at the bottom of the inlet of the anti-clogging assembly. The top of the settling conduit is connected to the bottom of the settling chamber and the settling conduit is connected to the bottom of the dust-laden airflow chamber assembly.

[0020] The beneficial effects of this application are as follows: Dust from the coal mill is discharged through the dust-laden airflow chamber assembly. The Venturi measuring tube assembly recycles the discharged clean gas, forming a Venturi effect. Discharge is achieved through a thickened nozzle at the tail end of the vertical guide pipe. The clean gas discharged through the thickened nozzle contains some dust. This dust is initially intercepted and collected in the settling chamber by the horn-shaped collection port and V-shaped guide plate, returning to the bottom of the dust-laden airflow chamber assembly. Subsequently, some dust will enter the connecting duct. The inclined perforation of the thickened dustproof plate also intercepts a small amount of dust from entering. Furthermore, the segmented dustproof cotton layer can completely prevent dust from entering the thickened duct. A dust collection zone is set between the segmented dustproof cotton layer and the thickened dustproof perforated plate. The collected dust will enter the settling chamber through the zone discharge pipe. After multiple dust isolations, the clean gas is purified, effectively preventing dust from the coal mill from entering the overall circulation system through the differential pressure transmitter. This avoids clogging of the vertical guide pipe and differential pressure transmitter, reduces daily maintenance workload, reduces the number of purgings, increases the service life of the differential pressure transmitter, and reduces maintenance investment, thus having certain economic benefits. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 A schematic diagram of the overall structure of the backflushing device for measuring the air volume of a coal mill is provided for the embodiments of this application;

[0023] Figure 2 A structural schematic diagram of the main cabin is provided for the embodiments of this application;

[0024] Figure 3 A schematic diagram of the horn-shaped collection port is provided for the embodiments of this application;

[0025] Figure 4 A structural schematic diagram of the cross-section of the horn-shaped collection port is provided for the embodiments of this application;

[0026] Figure 5 A structural schematic diagram of the cross-section of the thickened dustproof perforated plate is provided for the embodiments of this application.

[0027] In the diagram: 100, Dust-laden airflow chamber assembly; 110, Main chamber; 111, Platform; 112, Conical guide chamber; 113, Main material valve; 200, Venturi measuring tube assembly; 210, Vertical guide tube; 211, Differential pressure transmitter; 212, One-way control valve; 213, Thickened nozzle; 300, Anti-clogging assembly; 310, Horn-shaped collection port; 311, V-shaped guide plate; 312, Connecting guide tube; 313, Root gate valve; 314, Thickened guide tube; 315, Thickened dustproof perforated plate; 316, Segmented dustproof cotton layer; 317, Interval discharge pipe; 400, Settling assembly; 410, Settling chamber; 411, Settling guide tube. Detailed Implementation

[0028] The following detailed description, in conjunction with the accompanying drawings, outlines some embodiments of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0029] like Figures 1-5 As shown, the back-flushing device for measuring the air volume of a coal mill according to an embodiment of this application includes:

[0030] Dust-laden airflow chamber assembly 100 is connected to the coal mill;

[0031] The top of the Venturi measuring tube assembly 200 is connected to the interior of the dust-laden airflow chamber assembly 100, and the bottom of the Venturi measuring tube assembly 200 is connected to the bottom of the dust-laden airflow chamber assembly 100. The Venturi measuring tube assembly 200 and the dust-laden airflow chamber assembly 100 form a Venturi measurement effect. Dust separates itself in the dust-laden airflow chamber assembly 100 due to gravity, and clean gas enters the Venturi measuring tube assembly 200, thus preventing dust from entering the differential pressure transmitter 211 at the source.

[0032] The anti-clogging component 300 is installed on one side of the dust-laden airflow chamber assembly 100. The inlet of the anti-clogging component 300 is connected to the bottom of the venturi measuring tube assembly 200, and the outlet of the anti-clogging component 300 is connected to the top inlet of the venturi measuring tube assembly 200 through a conduit. The anti-clogging component 300 can block the dust adsorbed inside the venturi measuring tube assembly 200, thereby preventing the dust from entering the circulation equipment, affecting the life of the differential pressure transmitter 211, and reducing the number of maintenance times.

[0033] The settling component 400 is located at the bottom of the inlet of the anti-blocking component 300, and the outlet of the settling component 400 is connected to the bottom outlet of the dust-laden airflow chamber component 100. The settling component 400 can collect the dust blocked by the anti-blocking component 300 and then input it into the dust-laden airflow chamber component 100.

[0034] like Figures 1-2 As shown, the dust-laden airflow chamber assembly 100 includes a main chamber 110, a platform 111, and a conical guide chamber 112. The main chamber 110 is divided into an upper section and a lower section, which facilitates the early manufacturing and later transportation. The platform 111 is fixedly connected to the bottom of the upper section of the main chamber 110. The platform 111 is set at the top of the lower section of the main chamber 110. The top of the conical guide chamber 112 is connected to the bottom of the lower section of the main chamber 110, which facilitates the collection and circulation of dust.

[0035] Furthermore, a discharge valve 113 is installed at the outlet of the conical guide chamber 112 to facilitate control of the speed at which dust is discharged from the main chamber 110.

[0036] Furthermore, the inner walls of the main cabin 110 and the inner walls of the conical guide chamber 112 are both provided with wear-resistant ceramic layers. The ceramic layers reduce dust erosion and wear, and extend the service life of the device.

[0037] like Figures 1-2 As shown, the Venturi measuring tube assembly 200 includes a vertical guide tube 210, a differential pressure transmitter 211, and a one-way control valve 212. The side wall of the vertical guide tube 210 is connected to two connecting pipes arranged vertically, which are respectively connected to the interior of the dust-laden airflow chamber assembly 100. The differential pressure transmitter 211 is connected to the top of the vertical guide tube 210. The one-way control valve 212 is located in the middle of the vertical guide tube 210. A porous metal filter with a pore size ≤50μm is added at the inlet of the differential pressure transmitter 211 for fine filtration at the end and double anti-clogging protection for the differential pressure transmitter 211.

[0038] Furthermore, the bottom of the vertical guide pipe 210 is connected to a thickened nozzle 213, which extends into the interior of the inlet of the anti-clogging component 300. The vertical guide pipe 210 can extract clean gas from the interior of the main cabin 110 for subsequent recycling. The vertical section and the horizontal section of the vertical guide pipe 210 are connected by a 90° bend joint, and the bend curvature radius is ≥ 2 times the diameter of the vertical guide pipe 210.

[0039] Beneficial effects: Large curvature elbows reduce airflow disturbance and prevent secondary dust.

[0040] like Figures 3-5As shown, the anti-clogging component 300 includes a horn-shaped collection port 310, a V-shaped guide plate 311, a connecting conduit 312, a root gate valve 313, a thickened conduit 314, a thickened dustproof perforated plate 315, a segmented dustproof cotton layer 316, and an interval discharge pipe 317. The inner end of the horn-shaped collection port 310 is connected to the front end of the connecting conduit 312. The V-shaped guide plate 311 is fixedly installed at the inner bottom of the horn-shaped collection port 310. The horn-shaped collection port 310 and the V-shaped guide plate 311 can guide and redirect the airflow discharged from the thickened nozzle 213, thereby causing the dust carried in the airflow to be dispersed under the action of gravity. As dust falls and rubs against the horn-shaped collection port 310 and the V-shaped guide plate 311, it stops and accumulates at the opening of the horn-shaped collection port 310. The tail end of the horn-shaped collection port 310 is higher than the outlet of the thickened nozzle 213. To increase friction, the sidewalls of the horn-shaped collection port 310 and the V-shaped guide plate 311 can be covered with a ceramic layer, which can reduce dust erosion and wear and extend the life of the device. The tilt angle of the V-shaped guide plate 311 is set to 30-45 degrees, which has a concentrating effect. The V-shaped guide plate 311 and the outlet of the Venturi measuring tube assembly 200 are located at the same point. In conjunction with the above configuration, a root gate valve 313 is installed on the upper part of the connecting conduit 312 to control the airflow speed and slow it down. A thickened conduit 314 is connected to the tail end of the connecting conduit 312. A thickened dustproof plate 315 is fixedly installed inside the horn-shaped collection port 310 to block dust. A segmented dustproof cotton layer 316 is fixedly installed inside the connecting conduit 312 to further block dust. The top of the interval discharge pipe 317 is connected to the front end of the connecting conduit 312, and the inlet of the interval discharge pipe 317 is located within the thickened dustproof port. The bottom of the outlet of the interval discharge pipe 317 is connected to the side wall of the settling component 400 in the middle of the plate 315 and the segmented dustproof cotton layer 316. After the dust enters the connecting pipe 312 through the thickened dustproof plate 315, it will be completely blocked by the segmented dustproof cotton layer 316. The blocked dust will fall into the connecting pipe 312 between the segmented dustproof cotton layer 316 and the thickened dustproof plate 315. Then the accumulated dust will be discharged into the settling chamber 410 through the interval discharge pipe 317. The dust enters the circulation pipeline through multiple stages of dust blocking, thereby ensuring that no dust appears in the differential pressure transmitter 211.

[0041] To better block dust, a back-blowing fan can be installed at the base of the horn collection port 310, with the back-blowing direction opposite to the exhaust port direction of the thickened nozzle 213, so as to actively blow the dust into the settling chamber 410. At this time, a dust cover needs to be covered at the connection between the horn collection port 310 and the settling chamber 410 to prevent dust from flying and covering the thickened nozzle 213.

[0042] Furthermore, the holes on the thickened dustproof perforated plate 315 are oriented diagonally upwards, and the inclination angle of the holes on the thickened dustproof perforated plate 315 is set to 30 degrees-45 degrees to reduce dust from entering the connecting conduit 312.

[0043] Furthermore, the segmented dustproof cotton layer 316 is configured in two segments, which are located on both sides of the root gate valve 313, and can completely block dust.

[0044] like Figures 3-4 As shown, the settling assembly 400 includes a settling chamber 410 and a settling conduit 411. The settling chamber 410 is fixedly connected to the inlet of the anti-blocking assembly 300 and is located at the bottom of the inlet of the anti-blocking assembly 300. The top of the settling conduit 411 is connected to the bottom of the settling chamber 410 and the bottom of the settling conduit 411 is connected to the bottom of the dust-laden airflow chamber assembly 100. The dust collected in the settling chamber 410 will flow back into the conical guide chamber 112 and then be discharged. The conical structure at the bottom of the settling chamber 410 promotes dust accumulation.

[0045] Specifically, the working principle of the back-flushing device for measuring the air volume of the coal mill is as follows: Dust from the coal mill is discharged through the dust-laden airflow chamber assembly 100. The Venturi measuring tube assembly 200 recycles the discharged clean gas, forming a Venturi effect. The gas is discharged through a thickened nozzle 213 at the tail end of the vertical guide pipe 210. The clean gas discharged through the thickened nozzle 213 contains some dust. The dust is initially intercepted and collected in the settling chamber 410 by the horn-shaped collection port 310 and the V-shaped guide plate 311, then discharged back to the bottom of the dust-laden airflow chamber assembly 100. Afterward, some dust particles enter the connecting conduit 312. The inclined holes of the thickened dustproof plate 315 also... The system effectively intercepts small amounts of dust from entering the system, and the segmented dustproof cotton layer 316 completely prevents dust from entering the thickened conduit 314. A dust collection zone is set between the segmented dustproof cotton layer 316 and the thickened dustproof perforated plate 315. The collected dust enters the settling chamber 410 through the zone discharge pipe 317. Through multiple dust isolation processes, the clean gas is purified, effectively preventing dust from the coal mill from entering the overall circulation system through the differential pressure transmitter 211. This avoids clogging of the vertical guide pipe 210 and the differential pressure transmitter 211, reduces daily maintenance workload, decreases the frequency of purging, increases the service life of the differential pressure transmitter 211, and reduces maintenance investment, resulting in certain economic benefits.

[0046] The above are merely embodiments of this application and are not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application. It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

Claims

1. A back purging device for a coal mill airflow measuring instrument, characterized in that, include: A dust-laden airflow chamber assembly (100) is connected to a coal mill; A Venturi measuring tube assembly (200) is provided, the top of which is connected to the interior of the dust-laden airflow chamber assembly (100), and the bottom of which is connected to the bottom of the dust-laden airflow chamber assembly (100). An anti-clogging component (300) is disposed on one side of the dust-laden airflow chamber assembly (100). The inlet of the anti-clogging component (300) is connected to the bottom of the Venturi measuring tube assembly (200), and the outlet of the anti-clogging component (300) is connected to the top inlet of the Venturi measuring tube assembly (200) through a conduit. A settling assembly (400) is disposed at the bottom of the inlet of the anti-blocking assembly (300), and the outlet of the settling assembly (400) is connected to the bottom outlet of the dust-laden airflow chamber assembly (100).

2. The coal mill airflow meter back purging device according to claim 1, characterized in that, The dust-laden airflow chamber assembly (100) includes a main chamber (110), a platform (111), and a conical guide chamber (112). The main chamber (110) is divided into an upper section and a lower section. The platform (111) is fixedly connected to the bottom of the upper section of the main chamber (110). The platform (111) is located at the top of the lower section of the main chamber (110). The top of the conical guide chamber (112) is connected to the bottom of the lower section of the main chamber (110).

3. The coal mill airflow meter back purging device of claim 2, wherein, The outlet of the conical guide chamber (112) is equipped with a main discharge valve (113).

4. The coal mill airflow meter back purging device of claim 3, wherein, The inner wall of the main body (110) and the inner wall of the conical guide chamber (112) are both provided with a wear-resistant ceramic layer.

5. The coal mill airflow meter back purging device of claim 1, wherein, The Venturi measuring tube assembly (200) includes a vertical guide tube (210), a differential pressure transmitter (211), and a one-way control valve (212). The side wall of the vertical guide tube (210) is connected to two connecting pipes arranged vertically. The connecting pipes are respectively connected to the interior of the dust-laden airflow chamber assembly (100). The differential pressure transmitter (211) is connected to the top of the vertical guide tube (210). The one-way control valve (212) is located in the middle of the vertical guide tube (210).

6. The coal mill airflow meter back purging device of claim 5, wherein, The bottom of the vertical guide tube (210) is connected to a thickened nozzle (213), which extends into the interior of the inlet of the anti-clogging component (300).

7. The coal pulveriser airflow measuring instrument back purging device as claimed in claim 1 wherein, The anti-blocking assembly (300) comprises a horn collecting port (310), a V-shaped guide plate (311), a connecting conduit (312), a root gate valve (313), a thickened guide conduit (314), a thickened dustproof hole plate (315), a segmented dustproof cotton layer (316) and an interval discharge pipe (317), the inner end of the horn collecting port (310) is in communication with the front end of the connecting conduit (312), the V-shaped guide plate (311) is fixedly installed at the inner bottom of the horn collecting port (310), the inclination angle of the V-shaped guide plate (311) is 30-45 degrees, the V-shaped guide plate (311) is matched with the outlet of the Venturi measuring tube assembly (200), the root gate valve (313) is installed at the upper part of the connecting conduit (312), the thickened guide conduit (314) is in communication with the tail part of the connecting conduit (312), the thickened dustproof hole plate (315) is fixedly installed in the horn collecting port (310), the segmented dustproof cotton layer (316) is fixedly installed in the connecting conduit (312), the top of the interval discharge pipe (317) is in communication with the inner front end of the connecting conduit (312), the inlet part of the interval discharge pipe (317) is arranged in the middle part of the thickened dustproof hole plate (315) and the segmented dustproof cotton layer (316), and the outlet bottom of the interval discharge pipe (317) is in communication with the side wall of the sedimentation assembly (400).

8. The coal mill airflow meter back purging device of claim 7, wherein, The holes of the thickened dustproof hole plate (315) are arranged obliquely upwards, and the inclination angle of the holes of the thickened dustproof hole plate (315) is 30-45 degrees.

9. The coal mill airflow meter back purging device of claim 8, wherein, The segmented dustproof cotton layer (316) is provided in two sections, and the segmented dustproof cotton layer (316) is arranged at both sides of the root gate valve (313).

10. The coal mill airflow meter back purging device of claim 1, wherein, The sedimentation assembly (400) comprises a sedimentation cabin (410) and a sedimentation conduit (411), the sedimentation cabin (410) is fixedly connected with the inlet part of the anti-blocking assembly (300), the sedimentation cabin (410) is arranged at the inlet bottom of the anti-blocking assembly (300), the top of the sedimentation conduit (411) is in communication with the bottom of the sedimentation cabin (410), and the sedimentation conduit (411) is in communication with the bottom of the dust-containing airflow cabin assembly (100).

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