CN110389152B - Dust explosion simulation testing device and operation method thereof - Google Patents

Abstract

The invention discloses a dust explosion simulation testing device, which comprises a mechanical structure part and an electric control acquisition part, wherein the mechanical structure part comprises a mechanical structure part and a dust explosion simulation testing device; the mechanical structure part comprises an inlet explosion-proof pipe section, a detonation pipe section, a simulation pipe section and an outlet explosion-proof pipe section which are sequentially connected; the detonating tube section is provided with a powder supply tank, and the simulating tube section is provided with a powder adding port; the electric control acquisition part comprises a communication module, an igniter, a pressure sensor A, a pressure sensor B, a pressure sensor C and a data processing server, wherein the igniter, the pressure sensor A, the pressure sensor B, the pressure sensor C and the data processing server are respectively connected with the communication module. The detonation pipe section is respectively connected with the igniter and the pressure sensor A, the simulation pipe section is connected with the pressure sensor B, the outlet explosion-proof pipe section is connected with the pressure sensor C, and the powder supply tank is connected with the communication module. The invention realizes the high-speed on-line monitoring and acquisition of the multi-working-condition multi-mechanism broad-spectrum dust explosion characteristics and the aims of accident reproduction, hidden danger investigation and extreme value verification through the motion similarity principle of hydrodynamics and corresponding arrangement and operation.

Description

A dust explosion simulation test device and its operation method

technical field

The invention relates to the technical field of powder industrial overpressure explosion protection, in particular to a dust explosion simulation test device and an operation method thereof, which can simulate actual working conditions for a real-time monitoring and calibration device for powder explosion energy.

Background technique

In the powder industry with powder as the main operating medium, there are widespread process materials and products with high flow rate, high oxygen content and high accumulation pressure. Usually, powder industrial equipment is operated under pressure, and pressure vessels or air compressors are used to store or transport related process materials. Once subject to fluctuations in the external environment or human error, the related equipment is prone to potential safety hazards such as static electricity or overheating, which may seriously cause a violent explosion. In order to ensure the safety of the production process and the controllability in unexpected situations, the industry usually adopts overpressure relief or active spray devices as protective technical means. However, in the dust industry, there are too many factors that affect the explosion of powder, especially the flow velocity of the corresponding gas-solid two-phase flow and the pressure difference power during transportation are difficult to simulate, and the actual degree of harm cannot be determined after the explosion. Therefore, the assessment standards of safety equipment are mostly deduced based on experience and theoretical values, and the relevant tests are only carried out with explosion-proof tanks without initial flow rate and pressure difference, which makes it difficult to unify the evaluation standards in the industry. After the accident, there is no corresponding technical means to reproduce the internal mechanism of dust explosion.

On the basis of relevant research, Chinese researchers have proposed some test methods under ideal conditions, but at present, the flow rate and pressure of powder equipment under actual working conditions can be simulated, and the patent of test device and method for online acquisition and recording is almost the same. in a blank state. The patents that can currently be associated with this field are:

A dust explosion parameter test device (patent number: CN201620163426.3), which discloses a test device for collecting dust explosion characteristic parameters using a pressure-resistant tank under ideal conditions of no flow rate and pressure difference. A combined industrial dust explosion simulation demonstration system (patent number: CN201710182029.X), which discloses a combined dust explosion demonstration system using a programmable logic controller as an acquisition system. An experimental system for observing the propagation behavior of dust explosion flames (patent number: CN201710205389.7), which discloses a small dust explosion observation system using a fan to raise dust. However, the acquisition system architecture of the system disclosed in the above patent is a commercial module with common acquisition frequency, and the negative pressure dust removal or powder supply system commonly used in modern industry lacks the comparison and simulation effect of fluid mechanics.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to overcome the defects of the prior art, and to provide a dust explosion simulation test device and an operation method thereof, which can simulate the actual working condition of the powder explosion energy real-time monitoring and calibration device.

In order to solve the above technical problems, the dust explosion simulation test device provided by the present invention includes a mechanical structure part and an electric control acquisition part.

The mechanical structure part includes the inlet flameproof tube section, the detonator tube section, the simulated tube section and the outlet flameproof tube section, which are connected in sequence. A powder supply tank is arranged on the detonating tube section, and a powder feeding port is arranged on the simulated tube section.

The electronic control acquisition part includes a communication module, an igniter, a pressure sensor A, a pressure sensor B, a pressure sensor C and a data processing server respectively connected with the communication module.

The detonating pipe section is connected with the igniter and the pressure sensor A, the simulated pipe section is connected with the pressure sensor B, the outlet flameproof pipe section is connected with the pressure sensor C, and the powder supply tank is connected with the communication module.

As an improvement, the mechanical structure part also includes an air duct, a dust collector and a centrifugal dedusting fan connected in sequence; the air duct is connected with the outlet flameproof pipe section.

As an improvement, the dust collector adopts a bag dust collector, and a filter screen is set at the air inlet of the centrifugal dust collector.

As an improvement, pressure sensor A, pressure sensor B and pressure sensor C all use high-frequency dynamic pressure sensors.

As an improvement, a transparent observation pipe section is provided between the simulated pipe section and the outlet flameproof pipe section.

As an improvement, passive plate-type flameproof valves are respectively installed at the airflow inlet of the inlet flameproof pipe section and the airflow outlet of the outlet flameproof pipe section.

As an improvement, the outer wall of the detonating pipe section is opened with an outer pipe; the outlet of the powder supply tank is provided with a quick-opening solenoid valve, which is connected to the outer pipe.

As an improvement, the detonating tube section adopts a rectangular tube or a circular tube; along the air flow direction, in order to prevent the sedimentation speed of large particles of dust from being too fast, the ignition position is kept away from the central part of the dust cloud, and the outer nozzle of the detonating tube section is away from the air flow inlet of the detonating tube section. The ratio of the length of the detonator to the inner diameter of the section of the circular detonator section or the minimum side length of the section of the rectangular detonator section is not less than 2:1. The ratio of the inner diameter of the section or the minimum side length of the section of the rectangular detonator section is not greater than 3:1.

As an improvement, the ignition end of the igniter is installed on the inner wall of the detonator section. In the direction of airflow, the distance between the ignition end of the igniter relative to the outer nozzle of the detonator section and the inner diameter of the section of the circular detonator section or the rectangular detonator section The ratio of the minimum side length of the cross section is not more than 1:1, to ensure that the ignition end is as close to the center of the dust cloud as possible.

As an improvement, pipe threads or brazing are used for the opening at the firing end of the igniter.

As an improvement, the power supply components of the igniter are of intrinsically safe explosion-proof type.

As an improvement, in order to prevent the unfavorable consequences caused by ignition failure, and taking into account the demand for ignition energy in the dust cloud diffusion process, the ignition energy of the igniter is not less than twice the theoretical minimum ignition energy of the dust.

As an improvement, the pressure sensor A is connected to the side wall of the detonator section, and the acquisition element of the pressure sensor A is flush with the inner wall of the detonator section; the pressure sensor B is connected to the side wall of the simulated pipe section, and the acquisition element of the pressure sensor B is the same as the simulated pipe section. The inner wall of the pressure sensor C is connected to the side wall of the outlet flameproof pipe section, and the acquisition element of the pressure sensor C is flush with the inner wall of the outlet flameproof pipe section.

As an improvement, a rectangular pipe is used for the simulated pipe section, and the tensile strength σ _min of the pipe body material, the pipe wall thickness δ of the rectangular pipe, and the maximum side length L _r of the rectangular pipe section satisfy the following conditions:

Among them: P _max is the theoretical maximum explosion pressure of the selected dust, the unit is MPa.

As an improvement, a circular pipe is used for the simulated pipe section, and the tensile strength σ _min of the pipe material, the wall thickness δ of the circular pipe, and the outer diameter D _r of the circular pipe meet the following conditions:

Among them: P _max is the theoretical maximum explosion pressure of the selected dust, the unit is MPa.

As an improvement, the number of powder feeding ports is greater than or equal to 1. In order to prevent the openings on the pipe section from needing to be reinforced, the maximum size of the openings of the powder feeding ports should not be greater than the cross-sectional outer diameter of the circular simulated pipe section or the size of the rectangular simulated pipe section. 1/3 of the minimum side length of the section, the ratio of the distance between two adjacent powder feeding ports and the inner diameter of the section of the circular simulated pipe segment or the minimum side length of the rectangular simulated pipe segment is not less than 1:1.

As an improvement, the communication module is connected to the data processing server by twisted pair wires, the communication module is connected to the powder supply tank by a shielded wire, and the communication module is connected to the igniter by a copper core wire.

The above-mentioned dust explosion simulation test device assembly method and verification method include the following steps:

1. Bolt the passive plate flameproof valve to the airflow inlet of the inlet flameproof pipe section. The flameproof direction of the passive plate flameproof valve should be towards the airflow outlet of the inlet flameproof pipe section; the total length of the inlet flameproof pipe section must be greater than the installed flameproof pipe section. The minimum safe distance of the passive plate flameproof valve.

2. The airflow outlet of the inlet detonator section is flanged to the airflow inlet of the detonator section. Along the airflow direction, the length from the airflow inlet of the detonator section is the same as the inner diameter of the section of the circular detonator section or the length of the rectangular detonator section. The ratio of the minimum side length of the section is not less than 2:1 and the outer nozzle is set; the distance between the air flow outlet of the detonator section and the outer nozzle of the detonator section and the inner diameter of the section of the circular detonator section or the section of the rectangular detonator section The ratio of the minimum side length should not be greater than 3:1. The outer pipe is connected with the quick-opening electromagnetic valve of the powder outlet of the powder supply tank.

3. In the air flow direction of the detonator section, the ratio of the distance from the outer nozzle to the inner diameter of the section of the circular detonator section or the minimum side length of the rectangular section of the detonator section is not greater than 1:1. The opening is used to set the ignition ignition terminal of the device. The power bolt terminal of the igniter is set on the outer wall of the detonating tube section, and the copper core wire is used to connect the switch output of the communication module, and ensure that the power supply part of the igniter is intrinsically safe and explosion-proof, and the opening at the ignition end of the igniter should be Pipe threads or brazing ensure no leakage in high pressure environments.

4. The pressure sensor A is threaded on the side wall of the detonating tube section. The specific position can be independently selected between the ignition end of the igniter and the gas outlet of the detonating tube section according to the needs and the tolerance of the sensor. The acquisition element of pressure sensor A should be flush with the inner wall of the detonator section.

5. The gas outlet of the detonating pipe section is connected with the gas inlet of the simulated pipe section using a flange. The simulated pipe section can be customized according to the specific values of the parameters such as the pipeline form, dust concentration, and dust type to be tested.

6. The powder feeding port should be drilled on the outer wall of the simulated pipe section and installed by welding. The number of powder feeding ports can be more than one. The distance between the two adjacent powder feeding ports should be the same as the inner diameter of the section of the circular simulated pipe section or the rectangular simulated pipe section. The ratio of the minimum side length of the cross section shall not be less than 1:1; the maximum value of the opening size of the powder feeding port shall not exceed 1/3 of the inner diameter of the section of the circular simulated pipe section or the minimum side length of the rectangular simulated pipe section; The powder inlet should be installed with a flange skirt and equipped with a corresponding type of flange cover, which should be strictly sealed during the experiment.

7. Pressure sensor B is threaded on the side wall of the simulated pipe section. The specific position can be independently selected between the gas inlet and gas outlet of the simulated pipe section according to the needs and sensor tolerance; The inner wall of the pipe segment is flush.

8. The airflow inlet of the transparent observation pipe section is connected with the airflow outlet of the dust environment simulation pipe section through the flange. The air flow outlet of the transparent observation pipe section is connected to the air flow inlet of the outlet flameproof pipe section through a flange.

9. The airflow outlet of the outlet flameproof pipe section shall be bolted to install the passive plate type flameproof valve, and the outlet of the flameproof valve shall be bolted to the airflow inlet of the air duct; the total length of the outlet flameproof pipe section must be greater than the installed passive plate type flameproof valve The minimum safe distance for the valve.

10. The pressure sensor C is threaded on the side wall of the outlet flameproof pipe section. The specific position can be independently selected between the gas inlet and the gas outlet of the outlet flameproof pipe section according to the needs and the tolerance of the sensor; the acquisition of the pressure sensor C The element should be flush with the inner wall of the outlet flameproof pipe section.

11. The airflow outlet of the air duct is connected with the airflow inlet of the dust collector by flange; the centrifugal dust collector is connected with the gas outlet of the dust collector.

12. The communication module is connected to the data processing server using coaxial cables; the communication module and the data processing server use the same set of power switches for power-on and power-off.

The present invention also provides an operation method of the above-mentioned dust explosion simulation test device, comprising the following steps:

Step 1: Confirm that the interior of the dust explosion simulation test device is clean and dry by transparently observing the pipe section and the airflow inlet of the inlet flameproof pipe section; confirm the passive plate flameproof valve at the airflow inlet of the inlet flameproof pipe section and the outlet of the outlet flameproof pipe section. The passive plate flameproof valve is installed in place.

Step 2: According to the type of powder to be measured and the theoretical mass concentration, add dust into the simulated pipe section through the powder feeding port; the quality of the dust added should not be less than the product of the inner cavity volume of the simulated pipe section and the theoretical mass concentration of the dust to be measured ; Seal the powder port after adding the dust.

Step 3: Open the communication module and the data processing server, set the sampling frequency of the pressure signal and the ignition delay time of the igniter relative to the powder supply of the powder supply tank for the communication module, and start to collect the change of the pressure signal.

Step 4: Open the quick-opening solenoid valve at the powder outlet of the powder supply tank, and the igniter starts to work after the corresponding ignition delay time; pressure sensor A, pressure sensor B, and pressure sensor C transmit the pressure change to the data processing server Realize data processing, recording and storage.

Step 5: When the pressure values measured by pressure sensor A, pressure sensor B, and pressure sensor C return to the pressure value before the test, open the powder feeding port, and add sodium bicarbonate powder and sodium bicarbonate powder into the simulated pipe section. After the body is added, seal the powder filling port again and let it stand for more than half an hour.

Step 6: Disassemble according to the pipe section along the air flow direction, clean the pipe body, and return the passive plate type flameproof valve at the airflow inlet of the inlet flameproof pipe section and the passive plate type flameproof valve at the airflow outlet of the outlet flameproof pipe section.

As an improvement, in step 2, the mass of dust added should not be less than the product of the inner cavity volume of the simulated pipe section and the theoretical mass concentration of the dust to be measured.

As an improvement, in step 5, in order to prevent the secondary hazard of the remaining dust from explosion, sodium bicarbonate powder should be added to the simulated pipe section that has completed the experiment and returned to the pressure value before the test. Sodium bicarbonate is decomposed to generate carbon dioxide under the action of the residual temperature of the pipeline to ensure the safety inside the simulated pipeline. In order to make the carbon dioxide generated by decomposition sufficiently excessive, the amount of sodium bicarbonate powder added should be less than 2/3 of the quality of the dust used in the test; the added sodium bicarbonate powder should comply with GB/T1606-2008 "Industrial Carbonic Acid" Sodium bicarbonate powder specified in the standard of "Sodium Bicarbonate".

The beneficial effects of the present invention are as follows: (1) The present invention realizes high-speed online monitoring and collection of broad-spectrum dust explosion characteristics with multiple operating conditions and multiple mechanisms through the corresponding setting and operation of the invented device through the motion similarity principle of fluid mechanics. (2) The present invention determines the cause of the accident and realizes the reliability of the accident investigation result by adjusting the working conditions of the device of the present invention and reproducing the accident process according to the records of the process or area of the dust explosion accident. (3) The present invention simulates and tests the internal flow field of some new processes and new equipment in the powder or dust removal industry, eliminates relevant safety hazards, and realizes the reliability of process or equipment safety acceptance. (4) According to the relevant provisions of GB15577-2018 "Dust Explosion-Proof Safety Regulations", the present invention achieves the working purposes of accident recurrence, hidden danger investigation, and extreme value verification, and fills the gaps in related fields in my country.

Description of drawings

Fig. 1 is the structural representation of the present invention;

In the picture: 1—Inlet flameproof pipe section, 2—Initiation pipe section, 3—Powder supply tank, 4—Igniter, 5—Pressure sensor A, 6—Powder filling port, 7—Simulated pipe segment, 8—Pressure sensor B, 9 —transparent observation pipe section, 10—outlet flameproof pipe section, 11—pressure sensor C, 12—air duct, 13—dust collector, 14—centrifugal dust removal fan, 15—communication module, 16—data processing server.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings.

As shown in Figure 1, the dust explosion simulation test device provided by the present invention includes a mechanical structure part and an electric control acquisition part.

The mechanical structure includes the inlet flameproof pipe section 1, the detonation tube section 2, the simulated pipe section 7, the transparent observation pipe section 9, the outlet flameproof pipe section 10, the air duct 12, the dust collector 13 and the centrifugal dust removal fan 14.

The passive plate type flameproof valve is installed at the airflow inlet of the inlet flameproof pipe section 1 with bolts, and the airflow outlet of the inlet flameproof pipe section 1 is connected with the airflow inlet of the detonator section 2 by flange; The minimum safe distance of the explosion valve should be less than the length of the inlet flameproof pipe section 1.

Along the airflow direction, starting from the airflow inlet of the detonator section 2, open a hole at a position greater than twice the inner diameter of the detonator section 2 with a circular cross-section or twice the minimum side length of the detonator section 2 with a rectangular cross-section and set the outer Take over; the ratio of the length of the outer nozzle of the detonator section 2 to the air flow outlet of the detonator section 2 and the inner diameter of the detonator section 2 with a circular cross section or the minimum side length ratio of the detonator section 2 with a rectangular cross section is not greater than 3:1; the detonator section There is a powder supply tank 3 on the 2, and the powder outlet of the powder supply tank 3 is provided with a quick-opening solenoid valve, which is connected with the outer pipe of the detonating tube section 2; the powder supply tank 3 should use compressed air to push the powder in the tank into the detonating tube section. In 2, the nominal pressure of the compressed air should not be less than 4MPa, the amount of powder should not exceed 300g, and the type of powder should be the same as that in the simulated pipe section 7. The gas outlet of the detonating tube section 2 is connected with the gas inlet of the simulated tube section 7 using a flange. The role of the detonating tube section 2 is to generate enough explosion energy to lift up the dust in the simulated tube section 7 and ignite it smoothly, so as to complete the simulation of energy transfer and explosion characteristics.

The simulated pipe section 7 is used to simulate the dust environment, and it is provided with a powder feeding port 6, which should be welded on the outer wall of the simulated pipe section 7; the powder feeding port of the powder feeding port 6 should be a pipe flange cover and a matching pipe flange The maximum value of the opening size of the powder feeding port 6 cannot exceed the outer diameter of the circular simulated pipe section 7 or 1/3 of the minimum side length of the rectangular section when a rectangular tube is used; there can be multiple powder feeding ports 6, two adjacent ones. The distance between each powder feeding port 6 cannot be less than the inner diameter of the simulated pipe section 7 with a circular cross section, or the minimum side length of the simulated pipe section 7 with a rectangular cross section; the powder feeding port 6 can be welded at different positions of the simulated pipe section 7 according to specific needs, The powder inlet of the powder feeding port 6 should be strictly sealed with a flange cover in the experimental state; the airflow inlet of the transparent observation pipe section 9 is connected to the airflow outlet of the dust environment simulation pipe section 7 through the flange.

The simulated pipe section 7 can be customized according to the specific values of the parameters such as the pipeline form, dust concentration, dust type, etc. to be tested; the simulated pipe section 7 in this embodiment adopts a rectangular pipe, and the tensile strength σ _min of the pipe body material and the The tube wall thickness δ and the maximum side length L _r of the rectangular tube section satisfy the following conditions:

Among them: P _max is the theoretical maximum explosion pressure of the selected dust, the unit is MPa.

The gas flow outlet of the transparent viewing pipe section 9 is connected to the gas flow inlet of the outlet flameproof pipe section 10 through a flange.

The airflow outlet of the outlet flameproof pipe section 10 is bolted to install the passive plate type flameproof valve, and the outlet of the flameproof valve is connected to the airflow inlet of the air duct 12 with bolts; the passive plate type flameproof valve at the airflow outlet of the outlet flameproof pipe section 10 is the smallest The safety distance should be less than the length of the outlet flameproof pipe section 10 .

The airflow outlet of the air duct 12 is connected with the airflow inlet of the dust collector 13 using a flange, and the dust collector 13 adopts a bag dust collector.

A filter screen is set at the air inlet of the centrifugal dust removal fan 14 and is connected to the gas outlet of the dust removal collector 13; the gas flow of the centrifugal dust removal fan 14 during the experiment is similar to the gas flow of the simulated dust environment to achieve similar conditions .

The electronic control acquisition part includes an igniter 4 , a pressure sensor A5 , a pressure sensor B8 , a pressure sensor C11 , a communication module 15 and a data processing server 16 . The communication module 15 adopts a high-speed communication module.

The ignition energy of the igniter 4 should not be less than twice the theoretical minimum ignition energy of the dust; the power supply components of the igniter 4 are intrinsically safe and explosion-proof, and the power bolt terminals of the igniter 4 use copper core wires and the switch output of the communication module 15 For connection, the hole at the ignition end of the igniter 4 uses pipe threads or brazing, and the ignition end of the igniter 4 is installed on the inner wall of the detonator section 2. In the direction of airflow, the distance from the outer pipe of the detonator section 2 The ratio of the inner diameter of the detonator section 2 with a circular cross section to the minimum side length of the detonator section 2 with a rectangular cross section is not more than 1:1.

The pressure sensor A5 adopts a high-frequency dynamic pressure sensor. The pressure sensor A5 is connected to the side wall of the detonating tube section 2 using threads. The acquisition element of the pressure sensor A5 should be flush with the inner wall of the detonating tube section 2. The line is connected to the high-speed signal acquisition inlet of the communication module 15 .

The pressure sensor B8 adopts a high-frequency dynamic pressure sensor. The pressure sensor B8 is connected to the side wall of the simulated pipe section 7 using threads. The acquisition element of the pressure sensor B8 should be flush with the inner wall of the simulated pipe section 7. The transmission element of the pressure sensor B8 is shielded The line is connected to the high-speed signal acquisition inlet of the communication module 15 .

The pressure sensor C11 adopts a high-frequency dynamic pressure sensor. The pressure sensor C11 is connected to the side wall of the outlet flameproof pipe section 10 by means of threads. The acquisition element of the pressure sensor C11 should be flush with the inner wall of the outlet flameproof pipe section 10. The sending element is connected to the high-speed signal acquisition inlet of the communication module 15 using a shielded wire.

The communication module 15 is connected to the data processing server 16 by using twisted pair wires; the communication module 15 is connected to the powder supply tank 3 by using a shielded wire.

The above-mentioned dust explosion simulation test device assembly method and verification method include the following steps:

1. Bolt the passive plate type flameproof valve to the airflow inlet of the inlet flameproof pipe section 1. The flameproof direction of the passive plate type flameproof valve should be towards the airflow outlet of the inlet flameproof pipe section 1; the total length of the inlet flameproof pipe section 1 must be Greater than the minimum safe distance of the installed passive plate flameproof valve.

2. The air outlet of the inlet detonator section 1 is flanged to the air inlet of the detonator section 2, and the length and cross-section of the detonator section 2 along the airflow direction from the air inlet of the detonator section 2 are circular. The ratio of the minimum side length of the rectangular detonator section 2 is not less than 2:1, and the hole is opened and the outer nozzle is set; the distance between the air flow outlet of the detonator section 2 and the outer nozzle of the detonator section 2 and the cross section of the detonator section are circular. 2 The ratio of the minimum side length of the detonator section 2 with a rectangular inner diameter or cross section should not be greater than 3:1. The outer pipe is connected to the quick-open solenoid valve of the powder outlet of the powder supply tank 3 .

3. In the air flow direction of the detonator section 2, the ratio of the distance between the outer nozzle relative to the detonator section 2 and the inner diameter of the detonator section 2 with a circular cross section or the minimum side length of the detonator section 2 with a rectangular cross section is not greater than 1: A hole is opened at position 1 to set the ignition end of the igniter 4. The power bolt terminal of the igniter 4 is arranged on the outer wall of the detonating tube section 2, and is connected with the switch output of the communication module 15 by using a copper core wire, and ensure that the power supply part of the igniter 4 is intrinsically safe and explosion-proof, and the ignition end of the igniter 4 is The openings should be threaded or brazed to ensure no leakage in high pressure environments.

4. The pressure sensor A5 is threadedly connected to the side wall of the detonator section 2. The specific position can be independently selected between the ignition end of the igniter 4 and the gas outlet of the detonator section 2 according to the needs and sensor tolerance. The acquisition element of the pressure sensor A5 should be flush with the inner wall of the detonator section 2 .

5. The gas outlet of the detonating pipe section 2 is connected with the gas inlet of the simulated pipe section 7 using a flange. The simulated pipe section 7 can be customized according to the specific values of the parameters such as the pipeline form, dust concentration, and dust type to be tested.

6. The powder feeding port 6 should be drilled on the outer wall of the simulated pipe section 7 and installed by welding. The number of powder feeding ports 6 can be more than one. The distance between the two adjacent powder feeding ports 6 and the inner diameter of the section of the circular simulated pipe section 7 Or the ratio of the minimum side length of the section of the rectangular simulated pipe section 7 is not less than 1:1; the maximum size of the opening size of the powder feeding port 6 cannot exceed the outer diameter of the section of the circular simulated pipe section 7 or the minimum cross-section of the rectangular simulated pipe section 7 1/3 of the side length; the powder inlet of the powder inlet 6 should be installed with a flange skirt, and equipped with a corresponding type of flange cover, which is strictly sealed during the experiment.

7. The pressure sensor B8 is threaded on the side wall of the simulated pipe section 7. The specific position can be independently selected between the gas inlet and the gas outlet of the simulated pipe section 7 according to the needs and the tolerance of the sensor; the acquisition element of the pressure sensor B8 should be Flush with the inner wall of the simulated pipe section 7.

8. The airflow inlet of the transparent observation pipe section 9 is connected to the airflow outlet of the dust environment simulation pipe section 7 through a flange. The gas flow outlet of the transparent viewing pipe section 9 is connected to the gas flow inlet of the outlet flameproof pipe section 10 through a flange.

9. The airflow outlet of the outlet flameproof pipe section 10 is bolted to install a passive plate type flameproof valve, and the outlet of the flameproof valve is connected to the airflow inlet of the air duct 12 with bolts; the total length of the outlet flameproof pipe section 10 must be greater than the installed passive plate type flameproof valve. Minimum safe distance for plate flameproof valves.

10. The pressure sensor C11 is threaded on the side wall of the outlet flameproof pipe section 10. The specific position can be independently selected between the gas inlet and the gas outlet of the outlet flameproof pipe section 10 according to the needs and the sensor tolerance; pressure sensor C11 The collection element should be flush with the inner wall of the outlet flameproof pipe section 10 .

11. The airflow outlet of the air duct 12 is connected with the airflow inlet of the dust collector 13 by flange; the centrifugal dust collector 14 is connected with the gas outlet of the dust collector 13 .

12. The communication module 15 is connected to the data processing server 16 by using twisted pairs; the communication module 15 and the data processing server 16 use the same set of power switches for power-on and power-off.

The present embodiment also provides an operation method of the above-mentioned dust explosion simulation test device, comprising the following steps:

Step 1: Before starting the test, it should be confirmed that the inside of the test device is clean and dry through the transparent observation tube section 9 and the airflow inlet of the inlet flameproof tube section 1 and other visible windows; there is no visible dust, water droplets, oil droplets or other inside the device. Debris; confirm that the passive plate type flameproof valve at the airflow inlet of the inlet flameproof pipe section 1 and the passive plate type flameproof valve at the airflow outlet of the outlet flameproof pipe section 10 are installed in place and operate reliably; then the test steps can be carried out.

Step 2: After the safety measures are confirmed, a certain quality of dust should be added to the simulated pipe section 7 through the powder feeding port 6 according to the type of powder to be measured and the theoretical mass concentration; the quality of the added dust should not be less than the simulated pipe section 7. The product of the inner cavity volume and the theoretical mass concentration of the dust to be tested; after the dust is added, a flange cover should be used to reliably seal the powder addition port 6.

Step 3: After the powder adding operation is completed, turn on the power-on switches of the communication module 15 and the data processing server 16, wait for the communication module 15 and the data processing server 16 to start up, and set the pressure signal sampling frequency and igniter for the high-speed communication module 15. 4. Relative to the ignition delay time of the powder supply tank 3, and start to collect the change of the pressure signal.

Step 4: After the relevant test setting of the communication module 15 is completed, open the quick-opening solenoid valve at the powder outlet of the powder supply tank 3, and the igniter starts to work after the corresponding ignition delay time; at this time, the pressure sensor A5, pressure sensor B8, The pressure sensor C11 transmits the pressure change in the test device to the communication module 15, and realizes data processing, recording, and storage in the data processing server 16 through twisted pairs.

Step 5: When the pressure values measured by the pressure sensor A5, the pressure sensor B8 and the pressure sensor C11 return to the pressure value before the test, remove the flange cover of the powder feeding port 6, and add ultrafine hydrogen carbonate to the inside of the test device. Sodium powder, the amount of superfine sodium bicarbonate powder added should not be less than 2/3 of the quality of the dust used in the test; after the superfine sodium bicarbonate powder is added, use the flange cover again to seal the powder port 6 and let it stand for half. Hour.

Step 6: Half an hour after adding the superfine sodium bicarbonate powder, disassemble the dust explosion simulation test device according to the pipe section along the airflow direction, use a damp push rod to push the remaining dust out of the pipe section and collect it with a water-containing collection bag; Wipe the inner wall of the pipe section with a damp cloth and dry it, and return the passive plate flameproof valve at the airflow inlet of the inlet flameproof pipe section 1 and the passive plate flameproof valve at the airflow outlet of the outlet flameproof pipe section 10 to wait for the next test.

Embodiment 2:

The difference from the dust explosion simulation test device of the first embodiment is that the simulated pipe section 7 adopts a circular pipe, and the tensile strength σ _min of the pipe body material, the pipe wall thickness δ of the circular pipe, and the outer diameter D _r of the circular pipe satisfy the following: condition:

Among them: P _max is the theoretical maximum explosion pressure of the selected dust, the unit is MPa.

The above are only the preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, several improvements can be made without departing from the principles of the present invention, and these improvements should also be regarded as the present invention. scope of protection.

Claims (13)

1. a dust explosion simulation test device, comprising a mechanical structure part, an electric control acquisition part; it is characterized in that: the described mechanical structure part comprises the inlet flameproof pipe section (1), the detonation pipe section (2), the simulated pipe section ( 7) and the outlet flameproof pipe section (10); the detonation pipe section (2) is provided with a powder supply tank (3), and the simulated pipe section (7) is provided with a powder feeding port (6); The electronic control acquisition part includes a communication module (15), and an igniter (4), a pressure sensor A (5), a pressure sensor B (8), a pressure sensor C (11) and a pressure sensor (11) connected to the communication module (15) respectively. a data processing server (16); The detonating pipe section (2) is respectively connected with the igniter (4) and the pressure sensor A (5), the simulated pipe section (7) is connected with the pressure sensor B (8), and the outlet flameproof pipe section (10) is connected with the pressure sensor C (11). ) is connected, and the powder supply tank (3) is connected with the communication module (15); A transparent observation pipe section (9) is arranged between the simulated pipe section (7) and the outlet flameproof pipe section (10); The outer wall of the detonating pipe section (2) is perforated and an outer pipe is arranged; the outlet of the powder supply tank (3) is provided with a quick-opening electromagnetic valve, and the quick-opening electromagnetic valve is connected with the outer pipe; The detonator section (2) adopts a rectangular tube or a circular tube; the length of the outer nozzle of the detonator section (2) from the air flow inlet of the detonator section (2) is the same as the inner diameter or rectangle of the circular detonator section (2). The ratio of the minimum side length of the detonator section (2) is not less than 2:1, and the distance between the outer pipe of the detonator section (2) and the air outlet of the detonator section (2) is the same as the inner diameter of the circular detonator section (2) or The ratio of the minimum side length of the rectangular detonator section (2) is not greater than 3:1. 2. The dust explosion simulation test device according to claim 1 is characterized in that: the ignition end of the igniter (4) is installed on the inner wall of the detonating tube section (2), and the ignition end of the igniter (4) is connected to the inner wall of the detonator (2). The ratio of the distance between the outer nozzle of the detonator section (2) and the inner diameter of the circular detonator section (2) or the minimum side length of the rectangular detonator section (2) is not greater than 1:1. 3. The dust explosion simulation test device according to claim 2, characterized in that: the opening at the ignition end of the igniter (4) uses pipe threads or brazing. 4. The dust explosion simulation test device according to claim 2, characterized in that: the power supply part of the igniter (4) adopts intrinsically safe explosion-proof type. 5 . The dust explosion simulation test device according to claim 2 , wherein the ignition energy of the igniter ( 4 ) is not less than twice the theoretical minimum ignition energy of the dust. 6 . 6. The dust explosion simulation test device according to claim 1, characterized in that: the pressure sensor A (5) is connected to the side wall of the detonating tube section (2), and the collection element of the pressure sensor A (5) is connected to the detonation The inner wall of the pipe section (2) is flush; the pressure sensor B (8) is connected to the side wall of the simulated pipe section (7), and the acquisition element of the pressure sensor B (8) is flush with the inner wall of the simulated pipe section (7); The pressure sensor C (11) is connected to the side wall of the outlet flameproof pipe section (10), and the collecting element of the pressure sensor C (11) is flush with the inner wall of the outlet flameproof pipe section (10). 7. The dust explosion simulation test device according to claim 1, characterized in that: the simulated pipe section (7) adopts a rectangular pipe, and the tensile strength σ _min of the pipe body material, the pipe wall thickness δ, the maximum pipe cross section The side length L _r satisfies the following conditions:

Among them: P _max is the theoretical maximum explosion pressure of the selected dust. 8. The dust explosion simulation test device according to claim 1, characterized in that: the simulated pipe section (7) adopts a circular pipe, the tensile strength σ _min of the pipe body material, the pipe wall thickness δ, the outer pipe cross section The diameter D _r meets the following conditions:

Among them: P _max is the theoretical maximum explosion pressure of the selected dust. 9. The dust explosion simulation test device according to claim 1 is characterized in that: the quantity of the powder feeding port (6) is not less than 1, and the opening size of the powder feeding port (6) is not larger than a circular simulated pipe section (7) or 1/3 of the minimum side length of the rectangular simulated pipe segment (7), the distance between the two adjacent powder feeding ports (6) and the inner diameter of the cross-section of the circular simulated pipe segment (7) or rectangular The minimum side length ratio of the section of the simulated pipe segment (7) shall not be less than 1:1. 10. The dust explosion simulation test device according to claim 1, characterized in that: the communication module (15) is connected to the data processing server (16) by using a twisted pair cable, and the communication module (15) is respectively connected to the power supply by using a shielded wire. The powder tank (3) is connected, and the communication module (15) is connected with the igniter (4) by using a copper core wire. 11. A method of operation of the dust explosion simulation test device according to any one of claims 1-10, characterized in that it comprises the following steps: Step 1: Confirm that the interior of the dust explosion simulation test device is clean and dry by transparently observing the air flow inlet of the pipe section (9) and the inlet flameproof pipe section (1); confirm the passive plate flameproof valve at the airflow inlet of the inlet flameproof pipe section (1). Installed in place with the passive plate flameproof valve at the airflow outlet of the outlet flameproof pipe section (10); Step 2: According to the type of powder to be measured and the theoretical mass concentration, dust is added into the simulated pipe section (7) through the powder feeding port (6); after the dust is added, the powder feeding port (6) is sealed; Step 3: Open the communication module (15) and the data processing server (16), set the sampling frequency of the pressure signal and the ignition delay time of the igniter (4) relative to the powder supply of the powder supply tank (3) for the communication module (15), and Start to collect changes in pressure signals; Step 4: Open the valve at the powder outlet of the powder supply tank (3), and the igniter (4) starts to work after the corresponding ignition delay time; pressure sensor A (5), pressure sensor B (8), pressure sensor C ( 11) Transmit the situation of pressure change to the data processing server (16) to realize data processing, recording and storage; Step 5: When the pressure values measured by the pressure sensor A (5), the pressure sensor B (8), and the pressure sensor C (11) return to the pressure value before the test, open the powder feeding port (6), and send the pipe to the simulated pipe section. (7) add sodium bicarbonate powder inside, then seal the powder adding port (6) again and let stand, the standstill time is not less than half an hour; Step 6: Disassemble the pipe sections along the airflow direction, clean the pipe body, and return the passive plate type flameproof valve at the airflow inlet of the inlet flameproof pipe section (1) and the passive plate type flameproof valve at the airflow outlet of the outlet flameproof pipe section (10). bit. 12. The operation method according to claim 11, characterized in that: in step 2, the mass of the added dust should not be less than the product of the inner cavity volume of the simulated pipe section (7) and the theoretical mass concentration of the dust to be measured. 13. operating method according to claim 11 is characterized in that: in step 5, the add-on of the added sodium bicarbonate powder cannot be less than 2/3 of the dust quality used in the test.

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