Experimental device and method for analyzing dust explosion risk of non-closed bag-type dust collector

Abstract

The invention relates to a dust explosion risk analysis experimental device for a non-closed bag-type dust collector. The dust explosion risk analysis experimental device comprises an air injection base, a vacuum pump, an air storage tank, an electric spark generator and a discharge electrode. Dust explosion can be completed in an open space, so that the damage to a cloth bag and the surrounding environment can be researched when dust of the bag-type dust collector exposed in the air explodes, and meanwhile, the dust explosion test device has the characteristics of simplicity and convenience in operation, safety and reliability.

Description

Technical Field

[0001] The present invention belongs to the technical field of industrial dust explosion protection, and particularly relates to an experimental device and method for analyzing the dust explosion hazard of a non-enclosed bag filter. Background Technique

[0002] Through literature research, it is found that the central cloth bag of the safety setting of large dust collectors is most prone to dust explosion. Scholars are focusing on two aspects of research: the first research direction focuses on improving the explosion resistance performance of the dust collector's own structure; the second research direction focuses on the explosion venting measures after an explosion occurs inside the dust collector. For example, Li Chang et al. analyzed metal titanium powder using a 20L spherical device, systematically studied the minimum ignition temperature, minimum ignition energy, and explosion severity parameters of dust clouds at the micron and nanometer scales, as well as the inerting mechanism of nano-inert powder titanium dioxide; Su Hao et al. used a 1.2L Hartmann tube to study the minimum ignition energy MIE and minimum ignition temperature MIT of zirconium metal dust clouds; Yuan Chunmiao et al. built an explosion container with a volume of about 5L according to the DIN EN1893 standard and carried out a series of in-depth studies on converter gas. In the current field of combustible dust explosion research, most of the existing test systems are designed based on closed containers, and there are obvious limitations in the visualization of the dust explosion process. Although these closed test systems can simulate the explosion behavior of combustible dust in a confined space to a certain extent, due to the lack of visualization means, it is difficult to deeply observe and analyze the microscopic phenomena and dynamic changes during the explosion process.

[0003] Non-enclosed dust collectors, with their simple and flexible structures, play an important role in application scenarios that cannot be covered by some large dust collectors. The internal filtration bag filter, as a typical representative of non-enclosed dust collectors, uses an internal filtration method, and the cloth bag is directly exposed to the air. With the wide application of internal filtration bag filters in industrial production, it has become particularly urgent to deeply study the impact of dust explosion on the cloth bag. In actual applications, internal filtration bag filters often use a combination of multiple units. This usage method makes the dust explosion not only damage the single cloth bag where the explosion occurs, but also may cause a chain reaction to adjacent cloth bags. Therefore, on the basis of studying the impact of dust explosion on a single cloth bag, further exploring the action mechanism on adjacent cloth bags after dust explosion is of great significance for comprehensively evaluating the safety and reliability of internal filtration bag filters.

[0004] In view of the above situation, it is significantly necessary and urgent to construct an experimental device for analyzing the dust explosion hazard of a non-enclosed bag filter. In industrial production, the bags of internal filter bag filters are exposed to the air. When a dust explosion occurs inside the bag, its potential hazards and the response mechanism of the bag are not yet clear. By setting up this experimental device, the actual scenario of dust explosion inside the bag can be simulated under controllable conditions. This device can be used to study the hazards of the bag under the impact of dust explosion. Due to the presence of dust floating outside the bag, the spread and expansion of dust explosion do not solely depend on the situation inside the bag. The interaction between the external floating dust and the explosion inside the bag may also trigger a secondary explosion outside the bag. This experimental device can provide an effective platform for studying this complex interaction mechanism. By precisely controlling experimental parameters such as dust concentration, bag material, ignition energy, etc., the influence of different factors on the explosion behavior inside and outside the bag can be deeply analyzed. This has important theoretical and practical significance for comprehensively understanding the propagation law of dust explosion, evaluating the safety of bag filters, and formulating targeted protection measures. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the above technical defects and provide an experimental device and method for analyzing the dust explosion hazard of a non-enclosed bag filter.

[0006] To solve the above problems, the technical solution of the present invention is: an experimental device for analyzing the dust explosion hazard of a non-enclosed bag filter, characterized in that it includes a jet base, a rotary vane vacuum pump, a gas storage tank, an electric spark generator, and a discharge electrode;

[0007] The jet base includes a dispersion cap, a dispersion cap support column, a five-hole connection ring, a connection stud, and a base. A plurality of through holes are provided around the top of the base. The connection stud is provided at the bottom of the base and is connected by a threaded structure. The five-hole connection ring is provided at the center position of the base and is connected to the base by a threaded structure. The dispersion cap support column is provided on the top of the five-hole connection ring and is connected by a threaded structure. The dispersion cap is provided on the top of the dispersion cap support column;

[0008] A first air pipe is provided between the gas storage tank and the jet base. A vacuum pump is provided on the side of the gas storage tank away from the jet base. A second air pipe is provided between the gas storage tank and the vacuum pump. A precision negative pressure vacuum pressure gauge is provided on the top of the gas storage tank. A valve I is provided in the second air pipe, and a valve II is provided in the first air pipe;

[0009] The bottom of the discharge electrode penetrates through the through hole in the base. The top of the discharge electrode is a tip, and the bottom is a non-tip. A connecting wire is provided at the bottom of the discharge electrode. The connecting wire is connected to the positive high-voltage output terminal of the electric spark generator, and the negative terminal of the electric spark generator is grounded.

[0010] Furthermore, the discharge electrode is a copper needle-shaped electrode.

[0011] Furthermore, the connecting wire is sleeved with a high-voltage insulating sleeve, and an insulating layer is provided at the connection part between the connecting wire and the discharge electrode.

[0012] Furthermore, the vacuum pump used is a rotary vane vacuum pump.

[0013] An experimental method for analyzing the dust explosion hazard of a non-enclosed bag filter includes the following steps:

[0014] Step 1: Connect the vacuum pump to the bottom of the gas storage tank via a pipeline. The gas storage tank is connected to valve II through gas pipe 2, and the end of valve II is connected to the bottom of the jet base. Install the precision negative pressure vacuum gauge at the top of the gas storage tank.

[0015] Step 2: Install valve I between the vacuum pump and the gas storage tank, and valve II between the gas storage tank and the jet base.

[0016] Step 3: Insert the discharge electrode into the upper half through the through hole reserved in the base, ensure that the tip part of the discharge electrode is opposite to and extends out of the copper tip, and fix it. At the same time, two clips extending from the positive high-voltage output terminal of the spark generator are respectively clamped on the non-tip part of the discharge electrode.

[0017] Step 4: Start the vacuum pump, then open valve I and valve II, and then close the corresponding equipment to check the airtightness of the whole device.

[0018] Step 5: Start the spark generator. If a clearly visible electric arc appears at the tip part of the discharge electrode, it can be confirmed that the discharge is successful. If no arc phenomenon appears, the equipment should be checked in detail.

[0019] Step 6: Weigh a small amount of dust, evenly put it into the hemispherical bowl, put the cloth bag on the jet base, support the cloth bag with four brackets, and firmly fix it at the bottom of the cloth bag with a telescopic hoop.

[0020] Step 7: Start the test. First, start the vacuum pump and valve I to inject air into the gas storage tank. When it is observed that the precision negative pressure vacuum gauge shows that the air volume in the gas storage tank reaches the required index, immediately turn off the rotary vane vacuum pump and valve I. Then start the spark generator, and immediately open valve II to let the gas flow out of the gas storage tank to evenly blow up the dust to create the dust distribution environment required for the test.

[0021] Step 8: Perform dust cleaning. Use a vacuum cleaner to clean the residual dust on the cloth bag and the jet base to ensure the cleanliness of the device.

[0022] Step Nine: Repeat the experiment according to the operation steps of the above experiment to conduct the next experiment.

[0023] The advantages of the present invention compared with the existing technologies are as follows:

[0024] (1) The simulated experimental environment is more realistic: This device can simulate the propagation process of dust explosion in a more real open environment. Compared with the traditional closed container experiment, the experimental results are more authentic and reliable, helping researchers deeply understand the dynamic changes of dust explosion and providing more accurate data support for research.

[0025] (2) It can study the interaction and chain reaction: It can be used to study the impact of dust explosion on the surrounding environment and the interaction between dust explosion and other objects, which is of great significance for evaluating the hazard range and chain reaction of dust explosion and helps to formulate countermeasures in advance. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic structural connection diagram of an experimental device for analyzing the dust explosion hazard of a non-enclosed bag filter in the present invention.

[0027] As shown in the figure: 1. Spark generator; 2. Discharge electrode; 3. Dispersion cap; 4. Dispersion cap support; 5. Five-hole connection ring; 6. Connecting stud; 7. Base; 8. Rotary vane vacuum pump; 9. Valve I; 10. Gas storage tank; 11. Precision negative pressure vacuum gauge; 12. Valve II. DETAILED DESCRIPTION OF THE INVENTION

[0028] The following will further illustrate the detailed implementation manners of the present invention with reference to the accompanying drawings. The same components are denoted by the same reference numerals.

[0029] It should be noted that the terms "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to the directions in the drawings, and the terms "inner" and "outer" respectively refer to the directions towards or away from the geometric center of a specific component.

[0030] In order to make the content of the present invention more clearly understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0031] As Figure 1 shown, an experimental device for analyzing the dust explosion hazard of a non-enclosed bag filter includes a jet base, a rotary vane vacuum pump 8, a gas storage tank 10, a spark generator 1 and a discharge electrode 2;

[0032] The jet base includes a dispersion cap 3, a dispersion cap support 4, a five-hole connection ring 5, a connecting stud 6 and a base 7;

[0033] The jet base consists of a dispersion cap 3, a dispersion cap support column 4, a five-hole connection ring 5, a connection stud 6, and a base 7. A number of through holes are provided around the top of the base 7. The connection stud 6 is provided at the bottom of the base 7 and is connected by a threaded structure. The five-hole connection ring 5 is provided at the central position of the base 7 and is connected to the base 7 by a threaded structure. The dispersion cap support column 4 is provided at the top of the five-hole connection ring 5 and is connected by a threaded structure. The dispersion cap 3 is provided at the top of the dispersion cap support column 4. Threaded ports are provided at the joints of the dispersion cap 3, the dispersion cap support column 4, and the five-hole connection ring 5. Professional fixing means are used to accurately position and fasten the three fittings to ensure a stable connection with the base 7. Multiple through holes are provided in the peripheral area around the center of the base 7, including two reduced-diameter holes with slightly larger sizes, whose main purpose is to fix the discharge electrode 2. Additionally, there are four holes with slightly smaller sizes, which are specifically used to support the cloth bag used during the test.

[0034] There is an air pipe I between the gas storage tank 10 and the jet base. A vacuum pump 8 is provided on the side of the gas storage tank 10 away from the jet base. There is an air pipe II between the gas storage tank 10 and the vacuum pump 8. A precision negative pressure vacuum pressure gauge 11 is provided on the top of the gas storage tank 10. A valve I 9 is provided in the air pipe II, and a valve II 12 is provided in the air pipe I. The vacuum pump 8 and the gas storage tank 10 are both connected to the jet base 7 through air pipes. This part will be applied to jet treatment, and it is necessary to strictly ensure its excellent airtightness. A precision negative pressure vacuum pressure gauge 11 is provided above the gas storage tank 10, with a measuring range set in the interval of 0 to 1 MPa and a scale division value of 0.05 MPa. The gas distribution auxiliary component includes multiple sections of pipelines. The air pipe II is connected between the vacuum pump 8 and the gas storage tank 10 by a bolt connection method, and a valve I 9 is provided on this pipeline. Additionally, the air pipe I connects the gas storage tank 10 and the base 7 by a bolt connection, and a valve II 12 is provided on this pipeline. The bottom of the discharge electrode 2 penetrates through the through hole in the base 7. The top of the discharge electrode 2 is a tip, and the bottom is a non-tip. A connecting wire is provided at the bottom of the discharge electrode 2. The bottom of the discharge electrode 2 penetrates through the through hole in the base 7. The top of the discharge electrode 2 is a tip, and the bottom is a non-tip. A connecting wire is provided at the bottom of the discharge electrode 2. The discharge electrode 2 penetrates through the inner area of the base 7, with the tip located in the upper half. The non-tip part is connected to the positive high-voltage output terminal of the electric spark generator 1 through a connecting wire, and the negative electrode of the electric spark generator 1 is grounded.

[0035] The discharge electrode 2 is a copper needle-shaped electrode. The distance between the two tips in this test is 5 mm, which is used to detonate dust particles suspended in the air.

[0036] The connecting wire is equipped with a high-voltage insulating sleeve, and an insulating layer is provided at the connection part between the connecting wire and the discharge electrode to prevent the occurrence of high-voltage electric shock accidents.

[0037] The rotary vane vacuum pump 8 is used as the vacuum pump. This vacuum pump 8 utilizes the rotary motion of the rotary vane in the pump chamber to extract gas.

[0038] A test method for an experimental device for analyzing the explosion hazard of dust in an open bag filter. Step 1: Connect the rotary vane vacuum pump 8 to the bottom of the gas storage tank 10 via a pipeline; the gas storage tank 10 is sequentially connected to the solenoid valve and the bottom of the jet base 7 through pipelines, and the precision negative pressure vacuum pressure gauge 11 is installed at the top position of the gas storage tank 10.

[0039] Step 2: Install the valve I 9 between the rotary vane vacuum pump 8 and the gas storage tank 10, and the valve II 12 between the gas storage tank 10 and the jet base 7.

[0040] Step 3: Insert the discharge electrode 2 into the upper half through the threaded hole reserved on the jet base 7, ensure that the tip part of the discharge electrode 2 is opposite to and extends beyond the copper tip, and fix it. At the same time, two clips extending from the positive high-voltage output terminal of the spark generator 1 are respectively clamped on the non-tip part of the discharge electrode 2.

[0041] Step 4: Start the rotary vane vacuum pump 8, then open the valve I 9 and the valve II 12, and then close the corresponding equipment to check the airtightness of the entire device.

[0042] Step 5: Start the spark generator 1. If a clearly visible arc appears at the tip part of the discharge electrode 2, it can be confirmed that the discharge is successful; if no arc phenomenon appears, the equipment should be checked in detail.

[0043] Step 6: Weigh 0.9 g of corn starch for the test, evenly place it in the hemispherical bowl, put a pure cotton cloth bag with a volume of 0.0012 m3 on the jet base 7, support the cloth bag with four brackets, and firmly fix it at the bottom of the cloth bag with a telescopic hoop.

[0044] Step 7: Start the test. First, start the rotary vane vacuum pump 8 and the valve I 9 to inject air into the gas storage tank 10. When it is observed that the precision negative pressure vacuum pressure gauge 11 shows that the air volume in the gas storage tank 10 reaches 0.6 Mpa, immediately turn off the rotary vane vacuum pump 8 and the valve I 9; then start the spark igniter 1, adjust the voltage to 1.414 kv and the capacitance to 10 F, and then immediately open the valve II 12 to let the gas flow out of the gas storage tank 10, and use the blowing function of the dispersion cap 3 to evenly blow up the dust to create a dust distribution environment with a mass concentration of 750 g / m3.

[0045] Step 8: Dust cleaning treatment. Use a vacuum cleaner to clean the residual dust on the cloth bag and the jet base 7 to ensure the cleanliness of the device.

[0046] Step 9: Repeat the above experimental operation steps to conduct the next experiment.

[0047] The above describes the present invention and its implementation manners. Such description is not restrictive. What is shown in the drawings is only one of the implementation manners of the present invention, and the actual structure is not limited thereto. All in all, if those of ordinary skill in the art are inspired by it and, without departing from the gist of the present invention creation, design similar structural manners and embodiments to this technical solution without creative efforts, they shall fall within the protection scope of the present invention.

Claims

1. A non-enclosed bag filter dust explosion hazard analysis experimental device, characterized by: It comprises an air jet base, a rotary vane vacuum pump (9), a gas storage tank (10), an electric spark generator (1) and a discharge electrode (2); The jet base comprises a dispersion cap (3), a dispersion cap support (4), a five-hole connecting ring (5), a connecting stud (6), and a base (7); a plurality of through holes are opened around the top of the base (7); the connecting stud (6) is arranged at the bottom of the base (7) and connected with a threaded structure; the five-hole connecting ring (5) is arranged at the center of the base (7) and connected with the base (7) by a threaded structure; the dispersion cap (4) support is arranged at the top of the five-hole connecting ring (5) and connected with a threaded structure; the dispersion cap (3) is arranged at the top of the dispersion cap support (4); An air pipe 1 is provided between the air storage tank (10) and the jet base, a vacuum pump (8) is provided on the side of the air storage tank (10) away from the jet base, an air pipe 2 is provided between the air storage tank (10) and the vacuum pump (8), a precision negative pressure vacuum gauge (11) is provided on the top of the air storage tank (10), a valve Ⅰ (9) is provided in the air pipe 2, and a valve Ⅱ (12) is provided in the air pipe 1; The bottom of the discharge electrode (2) is inserted into a through hole in the base (7); the top of the discharge electrode (2) is a pointed tip and the bottom is a non-pointed tip; a connecting wire is provided at the bottom of the discharge electrode (2); the connecting wire is connected to the positive high voltage output end of the electric spark generator (1); and the negative end of the electric spark generator (1) is grounded.

2. According to claim 1, a non-enclosed bag filter dust explosion hazard analysis experimental device is characterized by: The discharge electrode (2) is a copper needle electrode.

3. According to claim 1, a non-enclosed bag filter dust explosion hazard analysis experimental device is characterized by: The connecting wire is sheathed with a high-voltage insulating sleeve on the outside, and the connecting portion between the connecting wire and the discharge electrode is provided with an insulating layer.

4. The non-enclosed bag filter dust explosion hazard analysis experimental device according to claim 1 is characterized by: The vacuum pump (8) is a rotary vane vacuum pump.

5. An experimental method for analyzing the dust explosion hazard of a non-enclosed bag filter, comprising the following steps: Step 1: Connect the vacuum pump (8) to the bottom of the gas storage tank (10) via a pipeline, the gas storage tank (10) is connected to the valve II (12) via the air pipe II, and the end of the valve II (12) is connected to the bottom of the jet base (7), and the precision negative pressure vacuum gauge (11) is installed at the top of the gas storage tank (10); Step 2: Install valve I (9) between the vacuum pump (8) and the gas storage tank, and valve II (12) between the gas storage tank (10) and the jet base (7); Step 3: Insert the discharge electrode (2) into the upper part through the through hole reserved in the base (7), ensure that the tip of the discharge electrode (2) is opposite to and extends out of the copper tip, and fix it for use, and at the same time, two clips extending from the positive high-voltage output end of the electric spark generator (1) are respectively clamped on the non-tip part of the discharge electrode (2); Step 4: Start the vacuum pump (8), then open valve I (9) and valve II (12), then close the corresponding equipment and perform an airtightness check on the entire device; Step 5: Start the spark generator (1). If a clearly visible arc appears at the tip of the discharge electrode (2), it can be confirmed that the discharge is successful. If no arc appears, the equipment should be inspected in detail. Step 6: Weigh a small amount of dust and evenly put it into the hemispherical bowl. Put the bag on the jet base, use four brackets to support the bag, and fix it firmly with a telescopic hoop at the bottom of the bag; Step 7: Start the test. First, start the vacuum pump (8) and valve I (9) to inject air into the gas storage tank (10). When the precision negative pressure vacuum gauge (11) shows that the amount of air in the gas storage tank (10) reaches the required index, immediately close the rotary vane vacuum pump (8) and valve I (9), then start the electric spark generator (1), and then open valve II (12) to allow gas to flow out of the gas storage tank (10) and blow up the dust evenly to create the dust distribution environment required for the test. Step 8: Dust removal: Use a vacuum cleaner to clean the dust remaining on the bag and the jet base to ensure the cleanliness of the device; Step 9: Repeat the experiment according to the operating steps of the above experiment to carry out the next experiment.

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