A multi-stage cascading venting test method incorporating a powdered combustion suppressant

Abstract

The application discloses a kind of multi-stage linkage explosion venting test methods combined with powdery combustion inhibitor, it is related to explosion-proof engineering and safety detection technical field;The method is by constructing with explosion venting device, ignition system, powdery inhibitor delivery system and pressure and optical sensor test cabin, uses PLC to realize ignition, pre-delivery, pressure relief trigger, synchronous inhibition and afterflame inhibition and so on multi-stage linkage control;And through pressure, temperature and flame sensor real-time acquisition of multi-dimensional data of explosion process;By before ignition, ignition instant and in the process of pressure relief with different doses of powdery inhibitor, the explosion suppression performance under different linkage strategies can be systematically evaluated;The application can simultaneously obtain peak pressure, pressure rise rate, flame propagation speed and re-burning conditions and other multi-parameters, realize the quantitative evaluation of the explosion suppression efficiency of powdery combustion inhibitor under multi-stage linkage explosion venting conditions, with the advantages of good data integrity, strong repeatability and suitable for standardization explosion-proof test method construction.

Description

Technical Field

[0001] This invention relates to the field of explosion-proof engineering and safety testing technology, specifically a multi-stage linkage explosion relief test method combining powdered combustion inhibitors. Background Technology

[0002] Mixtures of flammable gases and dust are highly susceptible to explosion in enclosed or semi-enclosed spaces. Traditional explosion relief tests typically evaluate only the pressure relief capacity of the container, paying less attention to parameters such as flame propagation, pressure rise rate (dP / dt), secondary combustion, and inhibitor release effectiveness. Modern explosion protection systems commonly employ powdered inhibitors to suppress explosions and block flames; however, existing testing methods generally suffer from the following shortcomings: 1. Single inhibitor intervention stage: Most methods only focus on the release of inhibitors before or at the moment of ignition, without involving multi-level linkage control, such as pre-release before depressurization, synchronous injection at the moment of depressurization, and suppression of residual fire after depressurization.

[0003] 2. Insufficient linkage response mechanism: Existing methods usually use a single valve or a single thin plate for explosion relief, and lack experimental methods for dynamic linkage and multi-stage response based on pressure changes and flame propagation characteristics.

[0004] 3. Incomplete data dimensions: Many traditional experiments only collect peak pressure and lack comprehensive data such as high-frequency pressure, flame propagation, inhibitor delivery curves, and re-ignition, making it impossible to fully evaluate the synergistic effect between inhibitors and linkage strategies.

[0005] Therefore, there is an urgent need for a test method that can simulate actual explosion-proof scenarios and verify the flame suppression efficiency of powdered combustion inhibitors in the coordinated explosion venting process at different stages, in order to evaluate the overall performance of explosion-proof systems and improve the reliability of engineering applications. Summary of the Invention

[0006] This invention provides a multi-stage linkage explosion relief test method that combines powdered combustion inhibitors to solve the technical problems mentioned in the background section.

[0007] This invention provides the following technical solution: a multi-stage linkage explosion relief test method combining powdered combustion inhibitors, comprising the following steps: S1: Prepare a mixture of combustible gas and dust in the test chamber; S2: Loading powdered combustion inhibitors into a controlled delivery system; S3: The mixture is ignited using an ignition device, and a multi-level linkage control process is executed through a PLC control system. S4: Powdered combustion inhibitors are added in the set sequence before ignition, at the moment of ignition, and during the depressurization process; S5: When the pressure inside the test chamber reaches the set threshold, the explosion relief device is triggered to release the pressure. S6: After depressurization, the second and third level inhibitors are deployed and the isolation action is triggered based on the flame propagation and pressure changes; S7: Real-time acquisition of test data through pressure, temperature, and optical sensors, calculation of peak pressure, pressure rise rate, and suppression efficiency, thereby enabling evaluation of the explosion suppression performance of powdered combustion inhibitors under multi-stage linkage explosion venting conditions.

[0008] Preferably, the powdered combustion inhibitor comprises one or more of bentonite, sodium bicarbonate, phosphate powder, and metal oxide powder.

[0009] Preferably, the powdered inhibitor delivery includes at least a first-stage pre-delivery, instantaneous delivery during pressure relief, and afterburner suppression delivery.

[0010] Preferably, the explosion relief device includes a crackable thin plate, a quick-opening pressure relief valve, or a multi-stage linkage pressure relief structure.

[0011] Preferably, the data display includes pressure-time curves, flame propagation speed curves, and inhibitor dosage-time curves.

[0012] Preferably, the multi-level linkage control process includes: ignition triggering, primary inhibitor pre-deployment, pressure relief threshold triggering, secondary inhibitor barrier deployment, and tertiary afterburner suppression steps.

[0013] Preferably, the test chamber has a volume of 0.1m³ to 10m³, which enables high-frequency pressure and optical data acquisition.

[0014] The testing method provided by this invention includes: Construct an explosion test chamber equipped with a pressure relief device, ignition system, inhibitor delivery system, and pressure and optical sensors.

[0015] Develop a strategy for dispensing powdered combustion inhibitors at multiple stages (before ignition, at the moment of ignition, during the depressurization process, and after depressurization).

[0016] A PLC control system is used to achieve multi-level linkage of ignition, inhibitor dispensing, pressure relief valve operation, and isolation valve operation.

[0017] Data were collected on pressure, flame propagation, inhibitor dosage curves, depressurization sequence, and secondary combustion.

[0018] The suppression efficiency is calculated by indicators such as peak pressure, pressure rise rate, and flame propagation speed, and the explosion suppression performance under different linkage strategies is comprehensively evaluated.

[0019] The present invention has the following beneficial effects: 1. Multi-stage inhibitor delivery: including pre-delivery, simultaneous delivery and afterburner suppression stages, to improve explosion suppression efficiency.

[0020] 2. Multi-level linkage explosion relief strategy: Realizes dynamic pressure relief triggered by pressure or time to simulate real accident scenarios.

[0021] 3. Strong data integrity: It can simultaneously acquire multi-dimensional data such as pressure, temperature, flame propagation, and deployment curve.

[0022] 4. Good repeatability: The inhibition effect can be repeatedly verified through the experimental matrix method, which is suitable for the formulation of standardized detection methods.

[0023] 5. Wide range of applications: Applicable to explosion suppression evaluation of different types of gases, dust and test chambers of different volumes. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of the test system of the present invention; Figure 2 This is a flowchart of the multi-level linkage control of the present invention; Figure 3 This is a schematic diagram of the pressure-time curve and the delivery curve of the present invention. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Example 1: Please refer to Figures 1-3 Construction and debugging of the experimental setup 1. Experimental Module Structure The experimental chamber is a steel cylindrical structure with a volume of 1 m³, and is equipped with: Replaceable explosion relief plate (rupture pressure 0.2MPa); Side observation window; Gas inlet and dust homogenization device; Sampling interface and safety valve.

[0027] Arranged inside the experimental chamber and along the depressurization channel: High-frequency pressure sensor (10kHz); Temperature thermocouple; Photoelectric flame detector; High-speed camera observation window.

[0028] 2. Powdered inhibitor delivery system It includes a pulse jet valve, a screw feeder, and a jet pipeline, which can deliver the material at different times according to a set mass. The jet nozzles are arranged on the top of the test chamber and in the pressure relief channel to form multi-point coverage.

[0029] 3. Multi-level linkage control unit Using a PLC control system, the following timing sequence is set: t=0: Ignition triggered; t=t1 (can be negative): Pre-administration of primary inhibitor; t=t2: When the pressure rises to the threshold, the pressure relief plate or active pressure relief valve is triggered; t=t3: Secondary inhibitor is administered to stop the leaking flame; t=t4: If residual fire is detected, trigger level three inerting or a large-dose injection. 4. Data Collection The system uses a high-speed acquisition card to simultaneously acquire pressure, temperature, delivery curves, and high frame rate images, recording indicators such as peak pressure, pressure rise rate, and flame propagation speed.

[0030] Example 2: Please refer to Figures 1-3 Multi-level linkage explosion relief test method 1. Experimental Preparation The mixed gas is charged according to the target concentration (e.g., 9% methane); Weigh out the powdered inhibitor (e.g., 1% sodium bicarbonate powder) and load it into the injection system; Calibrate the pressure sensor and delivery module.

[0031] 2. Test Execution Process (1) Start the data acquisition system.

[0032] (2) Execute the ignition action according to the PLC program.

[0033] (3) The primary inhibitor was pre-dose 20ms before ignition.

[0034] (4) When the pressure rises to the set value (e.g., 0.15MPa), the pressure relief plate is triggered to break.

[0035] (5) Inhibitors are simultaneously released around the pressure relief port at the moment of pressure relief to form an inhibition barrier.

[0036] (6) If secondary flame propagation is detected, a third-level suppression or inertization action is performed.

[0037] (7) Take samples and clean the equipment after the temperature and pressure have stabilized.

[0038] 3. Data Analysis Methods By comparing inhibitor-free trials with multi-stage coordinated trials: Peak pressure P_max Pressure rise rate (dP / dt)_max Flame propagation speed Did reignition occur? The suppression efficiency is calculated to verify the effectiveness of the multi-level linkage strategy.

[0039] Example 3: Please refer to Figures 1-3 Experimental matrix design Construct the following three-factor experimental matrix (each group is repeated three times): The experimental results were used to establish the functional relationship between inhibitor quality, release timing, and explosion suppression performance.

[0040] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0041] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A multi-stage linkage explosion venting test method combining powdered combustion inhibitors, characterized in that, Includes the following steps: S1: Prepare a mixture of combustible gas and dust in the test chamber; S2: Loading powdered combustion inhibitors into a controlled delivery system; S3: The mixture is ignited using an ignition device, and a multi-level linkage control process is executed through a PLC control system. S4: Powdered combustion inhibitors are added in the set sequence before ignition, at the moment of ignition, and during the depressurization process; S5: When the pressure inside the test chamber reaches the set threshold, the explosion relief device is triggered to release the pressure. S6: After depressurization, the second and third level inhibitors are deployed and the isolation action is triggered based on the flame propagation and pressure changes; S7: Real-time acquisition of test data through pressure, temperature, and optical sensors, calculation of peak pressure, pressure rise rate, and suppression efficiency, thereby enabling evaluation of the explosion suppression performance of powdered combustion inhibitors under multi-stage linkage explosion venting conditions.

2. The multi-stage linkage explosion venting test method combined with powdered combustion inhibitor according to claim 1, characterized in that: The powdered combustion inhibitor includes one or more of bentonite, sodium bicarbonate, phosphate powder, and metal oxide powder.

3. The multi-stage linkage explosion venting test method combined with powdered combustion inhibitor according to claim 1, characterized in that: The powdered inhibitor delivery includes at least one pre-delivery, instantaneous delivery during pressure relief, and afterburner suppression delivery.

4. The multi-stage linkage explosion relief test method combining powdered combustion inhibitors according to claim 1, characterized in that: The explosion relief device includes a crackable thin plate, a quick-opening pressure relief valve, or a multi-stage linkage pressure relief structure.

5. The multi-stage linkage explosion venting test method combined with powdered combustion inhibitor according to claim 1, characterized in that: The data displayed includes pressure-time curves, flame propagation speed curves, and inhibitor dosage-time curves.

6. The multi-stage linkage explosion relief test method combining powdered combustion inhibitors according to claim 1, characterized in that: The multi-level linkage control process includes: ignition triggering, primary inhibitor pre-deployment, pressure relief threshold triggering, secondary inhibitor barrier deployment, and tertiary afterfire suppression steps.

7. The multi-stage linkage explosion relief test method combining powdered combustion inhibitors according to claim 1, characterized in that: The test chamber has a volume of 0.1m³ to 10m³ and is capable of high-frequency pressure and optical data acquisition.

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