An explosion suppression system for a horizontal fluidized bed

Abstract

The utility model relates to the technical field of horizontal fluidized bed safety protection, specifically relates to an explosion suppression system for horizontal fluidized bed. The system of the present application realizes the targeted safety guarantee improvement through the collaborative design of each module, wherein the double-path redundant pressure detector can avoid the blind area and fault risk of single-path detection, cooperate with the uninterrupted redundant transmission of the main and standby relay module group, and ensure that the local explosion signal in the bed is quickly captured and transmitted to the controller; the false trigger interception module can effectively filter the false pressure signal caused by material feeding fluctuation and airflow impact, and in combination with the closed-loop control of the explosion suppression effect feedback module and the grading release valve, the release amount of the explosion suppression agent can be accurately adjusted according to the pressure change in the bed, thereby avoiding the secondary explosion caused by incomplete explosion suppression and reducing the waste of explosion suppression agent.

Description

Technical Field

[0001] This utility model relates to the field of safety protection technology for horizontal fluidized beds, specifically to an explosion suppression system for horizontal fluidized beds. Background Technology

[0002] Horizontal fluidized beds, as highly efficient gas-solid contact devices, are widely used in the drying, granulation, and reaction processes of powder materials due to their advantages of uniform material mixing and high heat and mass transfer efficiency. However, during operation, the bed is always in a two-phase flow state of "gas-powder." When the concentration of combustible powder is within the explosive limits, an explosion can easily occur if ignition sources such as electrostatic discharge or friction sparks from the equipment are encountered. The large length-to-diameter ratio and uneven airflow distribution of horizontal fluidized beds result in rapid explosion pressure propagation and a tendency for localized pressure surges, making it difficult for traditional explosion-proof systems to achieve rapid and precise explosion suppression.

[0003] Currently, most explosion-proof systems applied to horizontal fluidized beds are general-purpose designs, which are difficult to adapt to their special working conditions and have many technical shortcomings: First, the pressure detection link mostly uses single-point sensors, but the pressure distribution inside a horizontal fluidized bed varies greatly, and single-path detection is prone to "blind spots," making it impossible to capture local explosion pressure signals in time, or causing signal delays due to airflow fluctuations; Second, there is a lack of targeted effect feedback mechanisms after explosion suppression. Horizontal fluidized beds have a large volume, and combustible powder is easily left in the material accumulation area. If the explosion suppressant is not fully covered or the dosage is insufficient, it is very easy to trigger a secondary explosion. Traditional systems cannot monitor the pressure drop and powder residue status inside the bed in real time, making it difficult to eliminate the risk of reignition.

[0004] Given the structural characteristics and explosion risk patterns of horizontal fluidized beds, there is an urgent need for a new type of explosion suppression system to provide dedicated protection for the safe operation of horizontal fluidized beds. Utility Model Content

[0005] To achieve the above objectives, the present invention provides an explosion suppression system for a horizontal fluidized bed, specifically comprising: a dual-redundant pressure detector, a main / backup relay module group, a false trigger interception module, a controller, an explosion suppressant storage tank with a graded release valve, an explosion suppression effect feedback module, and an ignition source cutoff mechanism electrically connected to the controller; the dual-redundant pressure detector is electrically connected to the controller input terminal sequentially via the main / backup relay module group and the false trigger interception module, and the controller output terminal is electrically connected to the graded release valve of the explosion suppressant storage tank and the ignition source cutoff mechanism respectively; the explosion suppression effect feedback module is bidirectionally signal-connected to the controller; the main / backup relay module group includes a main relay module and a backup relay module redundantly connected, both of which are electrically connected to the dual-redundant pressure detector and the false trigger interception module.

[0006] The dual-redundant pressure detector includes two pressure detection units arranged in parallel, and the output terminals of both pressure detection units are electrically connected to the main and backup relay module group.

[0007] The main and backup relay module group also includes a switching control switch, which is electrically connected to the main relay module and the backup relay module respectively.

[0008] The false triggering interception module is equipped with a pressure signal interface and a flame signal interface, which are respectively connected to a dual-redundant pressure detector and a flame sensor.

[0009] The explosion suppression effect feedback module includes a pressure sensor, and the output terminal of the pressure sensor is electrically connected to the input terminal of the controller.

[0010] A solenoid valve is connected in series between the controller and the explosion suppressant storage tank, and the solenoid valve is electrically connected to the controller.

[0011] The beneficial effects of this invention are as follows: Targeted safety enhancements are achieved through the collaborative design of each module. Specifically, the dual-redundant pressure detector avoids blind spots and malfunction risks associated with single-channel detection. Combined with the uninterrupted redundant transmission of the main and backup relay modules, it ensures rapid capture of localized explosion signals within the chamber and transmission to the controller. The false trigger interception module effectively filters false pressure signals caused by material feeding fluctuations and airflow impacts. Combined with the explosion suppression effect feedback module and the closed-loop control of the staged release valve, the release amount of the explosion suppressant can be precisely adjusted according to changes in the chamber pressure, avoiding secondary explosions caused by incomplete suppression and reducing the waste of the explosion suppressant. Simultaneously, the linkage design between the controller and the ignition source cutoff mechanism can quickly cut off the ignition source while releasing the explosion suppressant, further reducing the risk of explosion spread. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the explosion suppression system for a horizontal fluidized bed in an embodiment of this application;

[0013] Figure 2 This is a schematic diagram of the dual-redundant pressure detector in the embodiments of this application;

[0014] Figure 3 This is a schematic diagram of the structure of the main and backup relay module group in the embodiments of this application. Detailed Implementation

[0015] The present application will be further described in detail below with reference to the accompanying drawings, so that those skilled in the art can better understand and implement the present invention, but the embodiments described are not intended to limit the present invention.

[0016] Example: Figure 1-3As shown, the explosion suppression system for a horizontal fluidized bed in this embodiment includes a dual-redundant pressure detector 1, a main and backup relay module group 2, a false trigger interception module 3, a controller 4, an explosion suppressant storage tank 5 with a graded release valve 51, an explosion suppression effect feedback module 6, and an ignition source cutoff mechanism 7. All components are electrically connected through copper core shielded wires, and the outer layer of the wires is wrapped with a high-temperature resistant insulating sleeve to adapt to the complex environment inside industrial equipment.

[0017] Among them, the dual-redundant pressure detector 1 is fixed to the inner cavity side wall of the explosion-proof equipment by threaded connection. The two pressure detection units (11, 12) are spaced 5-8cm apart to ensure that the pressure signal of the same area is collected and to avoid mutual interference. The main and backup relay module group 2 and the false trigger interception module 3 are integrated in the same metal protective box. The protective box is fixed to the outside of the equipment in a position that is easy to maintain by bolts, and the protection level reaches IP65. The controller 4 is a PLC controller, which is installed in the electrical control cabinet of the equipment. The distance between it and the explosion suppressant storage tank 5 does not exceed 3 meters to shorten the signal transmission distance.

[0018] The explosion suppressant storage tank 5 is made of stainless steel, and its volume is set according to the internal volume of the equipment. The graded release valve 51 on the top is connected to the tank body through a flange. The solenoid valve 52 connected in series between the graded release valve 51 and the controller 4 is normally closed and remains closed in the power-off state to improve safety. The pressure sensor 61 of the explosion suppression effect feedback module 6 and the dual-redundant pressure detector 1 are installed in a staggered manner to avoid signal duplication caused by overlapping detection areas. The ignition source cut-off mechanism 7 is linked to the power switch of the equipment and uses electromagnetic triggering to achieve rapid power-off.

[0019] Specifically, the dual-redundant pressure detector 1 includes a first pressure detection unit 11 and a second pressure detection unit 12, both of which are PTG501 high-precision pressure sensors with a measurement range of 0-10 MPa and an accuracy of ±0.5% FS. The two detection units are arranged in parallel, and their outputs are connected to the main / backup relay module group 2 via wires. During operation, they simultaneously acquire pressure signals from within the equipment. If one unit fails (such as signal interruption or abnormal values), the other unit can independently complete signal acquisition, avoiding system failure due to a single point of failure.

[0020] The main and backup relay module group 2 includes a main relay module 21, a backup relay module 22, and a switching control switch 23. Both the main and backup relay modules use RS485 signal repeaters, supporting signal amplification and long-distance transmission, and keeping the response delay of the controller 4 within 5ms. The switching control switch 23 is an electromagnetic automatic switching switch, electrically connected to both the main and backup relay modules. It monitors the operating status of the main relay module 21 in real time (such as power supply voltage and signal transmission strength). When the signal attenuation of the main module exceeds 30% or the power is lost, the switching control switch 23 completes the switching to the backup relay module 22 within 1ms, achieving uninterrupted signal transmission.

[0021] The false trigger interception module 3 is equipped with a pressure signal interface 31 and a flame signal interface 32, which are connected to the dual-redundant pressure detector 1 and the flame sensor 8 (model IR2000 infrared flame sensor) via wires, respectively. The module has a signal comparison circuit inside. When only the pressure signal exceeds the threshold and there is no flame signal, it is determined to be an instantaneous pressure fluctuation (such as caused by equipment vibration), and no trigger signal is transmitted to the controller 4. Only when the pressure signal exceeds the threshold and the flame signal is valid will the trigger signal be transmitted to the controller 4, effectively avoiding false operation.

[0022] The staged release valve 51 includes two release valve cores of different diameters (the large-diameter valve core is 15mm in diameter and the small-diameter valve core is 8mm in diameter). The two valve cores can be opened independently or simultaneously, controlled by the controller 4 according to the pressure signal strength. The pressure sensor 61 of the explosion suppression effect feedback module 6 is the same model as the dual-redundant pressure detector 1, which collects the pressure inside the equipment after the explosion suppressant is released in real time. When the pressure does not drop back to the safety threshold (usually below 0.1MPa) within 3 seconds, the controller 4 controls the staged release valve 51 to open the other valve core for secondary spraying.

[0023] The working process includes: the two detection units of the dual-redundant pressure detector 1 simultaneously collect the pressure signal inside the equipment, which is amplified by the main and backup relay module group 2 (the main relay module 21 works first) and then transmitted to the false trigger interception module 3. At the same time, the flame sensor 8 transmits the flame signal to this module.

[0024] The false trigger interception module 3 cross-verifies the pressure signal and the flame signal. If both meet the triggering conditions (pressure ≥ 0.5MPa and flame detected), the trigger signal is transmitted to the controller 4; if only one signal meets the criteria, the module blocks the signal transmission.

[0025] After receiving the trigger signal, the controller 4 immediately performs two operations: first, it controls the solenoid valve 52 to open, driving the corresponding valve core of the staged release valve 51 to release the explosion suppressant (both valve cores open simultaneously when the pressure is ≥1MPa); second, it controls the ignition source cut-off mechanism 7 to cut off the power supply and fuel supply of the equipment, thus blocking the ignition source.

[0026] The pressure sensor 61 of the explosion suppression effect feedback module 6 monitors pressure changes in real time. If the pressure does not drop to the safety threshold within 3 seconds, the controller 4 sends a secondary trigger signal to control the staged release valve 51 to continuously release the explosion suppressant until the pressure reaches the standard.

[0027] If the main relay module 21 of the main and backup relay module group 2 fails, the switching control switch 23 will automatically switch to the backup relay module 22 to ensure that the signal transmission is not interrupted and the entire switching process does not affect the system's response speed.

[0028] This embodiment significantly improves system stability through dual-path redundant detection and a primary / backup relay design; the signal cross-verification mechanism of the false trigger interception module reduces the false action rate; and the closed-loop control of graded release and effect feedback ensures thorough explosion suppression. It solves the problems of slow response and low reliability of traditional explosion-proof systems and can be widely used in industrial scenarios prone to explosion, such as chemical reactors and dust collection equipment.

[0029] The above embodiments are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications or equivalent substitutions made based on the technical solutions of the present invention should fall within the scope of protection of the present invention.

Claims

1. An explosion suppression system for a horizontal fluidized bed, characterized in that, include: The system comprises a dual-redundant pressure detector, a main / backup relay module group, a false trigger interception module, a controller, a suppressor storage tank with a graded release valve, a suppression effect feedback module, and an ignition source cutoff mechanism electrically connected to the controller. The dual-redundant pressure detector is electrically connected to the controller input terminal via the main / backup relay module group and the false trigger interception module. The controller output terminal is electrically connected to the graded release valve of the suppressor storage tank and the ignition source cutoff mechanism, respectively. The suppression effect feedback module is bidirectionally signal-connected to the controller. The main / backup relay module group includes a main relay module and a backup relay module that are redundantly connected, both of which are electrically connected to the dual-redundant pressure detector and the false trigger interception module.

2. The system according to claim 1, characterized in that, The dual-redundant pressure detector includes two pressure detection units arranged in parallel, and the output terminals of both pressure detection units are electrically connected to the main and backup relay module group.

3. The system according to claim 1, characterized in that, The main and backup relay module group also includes a switching control switch, which is electrically connected to the main relay module and the backup relay module respectively.

4. The system according to claim 1, characterized in that, The false triggering interception module is equipped with a pressure signal interface and a flame signal interface, which are respectively connected to a dual-redundant pressure detector and a flame sensor.

5. The system according to claim 1, characterized in that, The explosion suppression effect feedback module includes a pressure sensor, and the output terminal of the pressure sensor is electrically connected to the input terminal of the controller.

6. The system according to claim 1, characterized in that, A solenoid valve is connected in series between the controller and the explosion suppressant storage tank, and the solenoid valve is electrically connected to the controller.

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