Multi-furnace-type high-temperature pyrolyzing furnace protective gas intelligent regulation and control system and millisecond emergency response method

Abstract

The invention belongs to the technical field of safety control of industrial high-temperature equipment, and particularly relates to an intelligent control system for protective gas of a multi-furnace-type high-temperature pyrolyzing furnace and a millisecond emergency response method. The system comprises a sensing module, a control module and an execution module, the sensing module is used for collecting oxygen content and pressure data in the furnace body in real time and transmitting the data to the control module; the control module is used for receiving the data from the sensing module, carrying out real-time calculation and outputting a working instruction to the execution module at the same time; and an execution instruction of the execution module comes from the control module, and rapid air inlet and exhaust of the furnace body are achieved. The device is applied to a protective gas dynamic adjusting system of a sealed furnace body such as a tubular pyrolyzing furnace and a tunnel type high-temperature pyrolyzing furnace, and accurate regulation and control of oxygen content and quick response of pressure overrun can be realized through multi-sensor fusion and a self-adaptive control algorithm.

Description

Technical Field

[0001] The present invention belongs to the technical field of safety protection of high-temperature industrial equipment, and specifically relates to an intelligent control system for protective gas of multiple high-temperature pyrolysis furnaces and a millisecond-level emergency response method. Background Art

[0002] Traditional shielding gas control systems utilize PID control, with an average time of ≥3 seconds from detecting excessive oxygen levels to completing gas replacement. Experimental data shows that when the oxygen content in the furnace suddenly rises to 2%, the existing system takes 2.8 seconds to reduce it to the safe threshold (<0.5%), failing to interrupt the chain oxidation reaction. Conventional single-point detection systems have blind spots in large tunnel furnaces. An accident report from a lithium battery material plant revealed that the control system failed to trigger an alarm even when the local oxygen concentration in the rear section of the furnace reached 1.8%. Existing pressure relief valves rely on a mechanical spring mechanism, which is prone to oscillation when the pressure fluctuation frequency exceeds 10 Hz. Numerical simulations show that when the furnace pressure increases at a rate of 15 MPa / s, the pressure overshoot of the traditional system reaches 32%. Summary of the Invention

[0003] To address the shortcomings of the aforementioned prior art, the present invention aims to provide a dynamic shielding gas regulation system and millisecond-level emergency response method for sealed furnaces, such as rotary pyrolysis furnaces, tubular pyrolysis furnaces, and tunnel-type high-temperature pyrolysis furnaces. This system utilizes multi-sensor fusion to achieve precise oxygen content control and rapid response to pressure overruns. This system effectively maintains heat within the furnace and meets the sealing requirements of high-temperature furnaces.

[0004] The technical solution of the present invention is specifically described as follows.

[0005] The present invention provides a multi-furnace high-temperature pyrolysis furnace protection gas intelligent control system, comprising a sensor module, a control module and an execution module; wherein: The sensing module includes a gas monitoring array and a pressure sensing network. The gas monitoring array is used to collect data on the oxygen content in the furnace in real time and transmit the data to the control module. The gas monitoring array is composed of several oxygen sensors arranged along the axial direction of the furnace. The pressure sensing network is used to monitor and collect pressure parameters in the furnace in real time and transmit the data to the control module. The pressure sensing network includes several pressure sensors installed in the front, middle and rear sections of the furnace. The control module receives data from the sensor module, performs real-time calculations, and outputs work instructions to the execution module. The control module includes an adaptive feedforward compensation module, a fuzzy PID controller, and a pressure gradient warning module. The adaptive feedforward compensation module is used to predict gas demand based on furnace temperature T and material quantity M. The fuzzy PID controller is used to calculate the pressure relief volume. The pressure gradient warning module is used to trigger emergency pressure relief. The execution module, whose execution instructions come from the control module; the execution module includes a high-speed solenoid valve group, an air pump group and a flow regulator; the high-speed solenoid valve group includes an air intake valve and an exhaust gas discharge valve. The high-speed solenoid valve group actively intakes and exhausts air through the air pump, and adjusts the air pump flow through the flow regulator to achieve rapid intake and exhaust of gas in the furnace body.

[0006] In the present invention, the oxygen sensors are TDLAS laser oxygen sensors, which are 9-21 in number; the optical paths of the TDLAS laser oxygen sensors are arranged along the axial direction of the furnace body, generally in a zigzag arrangement along the axis, and are arranged close to the dead air zone of the furnace body or the area with slow gas flow rate.

[0007] In the present invention, the adaptive feedforward compensation module predicts gas demand based on furnace temperature T and material quantity M as follows: Q=K1T+K2M, where Q represents nitrogen flow, K1 represents temperature compensation coefficient, and K2 represents material consumption weight.

[0008] In the present invention, the method for calculating the pressure relief amount by the fuzzy PID controller is as follows: ΔP=α*(P max -P min )+β*dP / dt; Among them, α represents the fuzzy ratio coefficient, which ranges from 0.1 to 2.0; P max Indicates the maximum pressure value in the current sampling period; P min Indicates the minimum pressure value in the current sampling period; β indicates the fuzzy differential coefficient, and dP / dt indicates the pressure change rate.

[0009] In the present invention, the control module also includes a safety monitoring module, which is used to achieve three-dimensional oxygen concentration field reconstruction and real-time mapping of the oxygen content distribution in the furnace.

[0010] In the present invention, the pressure gradient warning module triggers emergency pressure relief when the pressure difference between adjacent sensors is greater than 0.03 MPa / m.

[0011] In the present invention, when the reading of any oxygen sensor is greater than 0.8%, the intake valve and the air pump are opened to intake air, and the exhaust gas discharge valve is opened synchronously.

[0012] In the present invention, the intake valve adopts a two-stage series structure, includes a pilot-operated high-speed solenoid valve, and has a response time of ≤2ms.

[0013] The present invention also provides a millisecond-level emergency response method for the above-mentioned system, comprising the following steps: 1) Data Collection The oxygen sensor collects the concentration data in the furnace body, and the pressure sensor collects the pressure data in the furnace body; the collected data are uploaded to the adaptive feedforward compensation module and the pressure gradient warning module of the control module respectively; 2) Emergency Response When the reading of any oxygen sensor is greater than 0.8%, the adaptive feedforward compensation module calculates the required nitrogen flow rate Q, opens the high-speed solenoid valve and the air pump, reaches the designed flow rate within 8ms, and the exhaust valve is synchronously opened to an opening angle of θ=0.65*Q; 3) Stress control strategies When the pressure gradient is greater than 0.03 MPa / m, the fuzzy PID controller calculates the pressure relief volume ΔP, and the servo motor drives the exhaust gas discharge valve to the target position with a full stroke time of ≤0.6s.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The present invention realizes automatic monitoring and autonomous regulation of the pressure in the furnace by utilizing a pressure gradient early warning module; and realizes autonomous regulation of the oxygen and nitrogen content by utilizing multiple oxygen sensors, so that the overall adjustment time of the system is controlled at the millisecond level. The traditional protective gas adjustment time is about 2.8 seconds, which greatly improves the protective gas response speed and greatly improves the high-temperature furnace's ability to prevent and reduce potential explosion risks. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0016] Figure 1 Diagram of the control system of the rotary pyrolysis furnace for lithium battery materials; Among them, the reference numerals in the figures are: 1-15, TDLAS laser oxygen sensor; 16-18, pressure sensor; 19, battery material; 20, large gear; 21, roller; 22, rotary kiln body; 23, support roller; 24, rotary kiln box; 25, nitrogen inlet solenoid valve; 26, nitrogen outlet solenoid valve; 27, air inlet pipe; 28, air outlet pipe; 29, air intake pump; 30, exhaust pump. DETAILED DESCRIPTION

[0017] The technical solution of the present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0018] The present invention provides an intelligent control system for protective gas and a millisecond-level emergency response. In order to achieve the above-mentioned purpose, the technical solution adopted in this application is: a laser oxygen sensor, a high-speed solenoid valve and an air pump group, and an industrial control computer are installed on the furnace body, and the monitoring software establishes a three-dimensional oxygen concentration field. The pressure difference between adjacent sensors can trigger a pressure gradient warning, and the exhaust gas exhaust valve is opened urgently to release the pressure.

[0019] The system includes multiple TDLAS laser oxygen sensors, a piezoresistive sensor, a high-speed solenoid valve, and an air pump assembly (including intake and exhaust valves, an air pump), along with a built-in adaptive feedforward compensation module. Monitoring software reconstructs a three-dimensional oxygen concentration field and provides a pressure gradient warning.

[0020] 1. Sensor module Gas monitoring sensor array: consists of 9-21 TDLAS laser oxygen sensors, arranged in a zigzag pattern along the furnace axis, with a measurement range of 0-5% O2 and a resolution of ≤0.01%, providing data support for timely blocking of the chain oxidation reaction in the furnace; pressure sensing network: contains 3 piezoresistive sensors, installed at the front, middle and rear sections of the furnace, with a measurement range of 0-2MPa and a nonlinear error of ≤0.05%FS.

[0021] 2. Execution module High-speed solenoid valve and air pump group: Contains nitrogen inlet valve and exhaust valve, response time ≤5ms, flow range 5-200L / s, servo motor driven flow regulator, positioning accuracy ±0.1°, full stroke time ≤0.8s, air intake and exhaust are actively controlled by the air pump, and rapid gas intake and exhaust are achieved by adjusting the air pump flow.

[0022] 3. Control module Equipped with a Xilinx Zynq UltraScale+ MPSoC industrial control computer, it features a built-in adaptive feedforward compensation module and a fuzzy PID controller that predicts gas demand based on furnace temperature (T) and material quantity (M). Its parameter self-tuning cycle is ≤1ms, and its safety monitoring software establishes a three-dimensional oxygen concentration field with a spatial resolution of ≤10cm³. When the pressure difference between adjacent sensors exceeds 0.03MPa / m, a pressure gradient warning is triggered, triggering the emergency opening of the exhaust valve to release pressure.

[0023] The present invention relies on oxygen sensors and pressure sensors, and uses a control module to control the air pump to achieve rapid response and achieve ventilation. When the furnace is working, such as a tubular furnace, pyrolyzing certain materials, if there is a crack in the glass tube, a small leak will cause the atmosphere in the furnace to change. In order to reduce the risk of explosion, a large amount of nitrogen must be quickly fed in to achieve the function of protecting the furnace body.

[0024] The following are specific examples.

[0025] like Figure 1As shown, the rotary pyrolysis furnace includes a large gear 2, a roller 21, a rotary kiln body 22, a supporting wheel 23 and a rotary kiln box 24; the furnace body of the rotary pyrolysis furnace is filled with battery material 19, and several TDLAS laser oxygen sensors 1-15 are arranged axially. Pressure sensors 16-18 are installed in the front, middle and rear sections of the furnace body respectively. A nitrogen inlet solenoid valve 25 is provided at one end of the furnace body, and the nitrogen inlet solenoid valve 25 is respectively connected to the air intake pump 29 and the air intake pipe 27. A nitrogen outlet solenoid valve 26 is provided at the other end of the furnace body, and the nitrogen outlet solenoid valve 26 is respectively connected to the exhaust pump 30 and the air outlet pipe 28.

[0026] 1. System Configuration As shown in Table 1.

[0027] Table 1 System Configuration

[0028] 2. Control Logic Implementation 1. Data Collection: 15 oxygen sensors upload data at a rate of 1000 times per second; The pressure sensor transmits via 4-20mA HART protocol; 2. Emergency Response Process: When any oxygen sensor reading is greater than 0.8%: a. Feedforward compensation module, calculates the required nitrogen flow Q=K1 T+K 2 M (K1=0.15, K2=2.4); b. Open the high-speed solenoid valve and air pump to reach the designed flow rate within 8ms; c. The exhaust valve is opened synchronously to an opening angle θ = 0.65*Q; 3. Pressure control strategy: When the pressure gradient is greater than 0.05 MPa / m: a. Fuzzy PID controller calculates the pressure relief volume ΔP=α*(P max -P min )+β*dP / dt; b. The servo motor drives the exhaust valve to the target position, and the full stroke time is ≤ 0.6s.

[0029] 3. Performance test data are as follows: 1. Oxygen control response: 23ms from 0.8% to 0.5% (3.2s for traditional systems); 2. Pressure stability: Under ±0.15MPa disturbance, control error ≤0.7%; 3. Fault coverage: The sensor network can detect more than 95% of local anomalies.

Claims

1. An intelligent control system for protective gas of multi-furnace high-temperature pyrolysis furnaces, characterized in that: It includes a sensing module, a control module and an execution module; wherein: The sensing module includes a gas monitoring array and a pressure sensing network. The gas monitoring array is used to collect data on the oxygen content in the furnace in real time and transmit the data to the control module. The gas monitoring array is composed of several oxygen sensors arranged along the axial direction of the furnace. The pressure sensing network is used to monitor and collect pressure parameters in the furnace in real time and transmit the data to the control module. The pressure sensing network includes several pressure sensors installed in the front, middle and rear sections of the furnace. The control module receives data from the sensor module, performs real-time calculations, and outputs work instructions to the execution module. The control module includes an adaptive feedforward compensation module, a fuzzy PID controller, and a pressure gradient warning module. The adaptive feedforward compensation module is used to predict gas demand based on furnace temperature T and material quantity M. The fuzzy PID controller is used to calculate the pressure relief volume. The pressure gradient warning module is used to trigger emergency pressure relief. The execution module, whose execution instructions come from the control module; the execution module includes a high-speed solenoid valve group, an air pump group and a flow regulator; the high-speed solenoid valve group includes an air intake valve and an exhaust gas discharge valve. The high-speed solenoid valve group is actively used for air intake and exhaust by the air pump, and the air pump flow is adjusted by the flow regulator to achieve rapid air intake and exhaust of the furnace body.

2. The intelligent control system for protective gas of multiple high-temperature pyrolysis furnaces according to claim 1 is characterized in that: The oxygen sensors are TDLAS laser oxygen sensors, which are 9-21 in number; the optical paths of the TDLAS laser oxygen sensors are arranged along the axial direction of the furnace body, and are generally arranged in a zigzag pattern along the axis, close to the dead air zone of the furnace body or the area with slow gas flow rate.

3. The intelligent control system for protective gas of multiple high-temperature pyrolysis furnaces according to claim 1 is characterized in that: The adaptive feedforward compensation module predicts gas demand based on furnace temperature T and material quantity M as follows: Q=K1T+K2M, where Q represents nitrogen flow, K1 represents temperature compensation coefficient, and K2 represents material consumption weight.

4. The intelligent control system for protective gas of multiple high-temperature pyrolysis furnaces according to claim 1 is characterized in that: The method for calculating the pressure relief amount by the fuzzy PID controller is as follows: ΔP=α*(P max -P min )+β*dP / dt; Among them, α represents the fuzzy ratio coefficient, which ranges from 0.1 to 2.0; P max Indicates the maximum pressure value in the current sampling period; P min Indicates the minimum pressure value in the current sampling period; β indicates the fuzzy differential coefficient, and dP / dt indicates the pressure change rate.

5. The intelligent control system for protective gas of multiple high-temperature pyrolysis furnaces according to claim 1 is characterized in that: The control module also includes a safety monitoring module, which is used to achieve three-dimensional oxygen concentration field reconstruction and real-time mapping of the oxygen content distribution in the furnace.

6. The intelligent control system for protective gas of multiple high-temperature pyrolysis furnaces according to claim 1 is characterized in that: The pressure gradient warning module triggers emergency pressure relief when the pressure difference between adjacent sensors is greater than 0.03MPa / m.

7. The intelligent control system for protective gas of multiple high-temperature pyrolysis furnaces according to claim 1 is characterized in that: When the reading of any oxygen sensor is greater than 0.8%, the intake valve and the air pump are opened to intake air, and the exhaust valve is opened synchronously.

8. The intelligent control system for protective gas of multiple high-temperature pyrolysis furnaces according to claim 1 is characterized in that: The intake valve adopts a two-stage series structure, includes a pilot-operated high-speed solenoid valve, and has a response time of ≤2ms.

9. A millisecond-level emergency response method for a system according to any one of claims 1 to 8; characterized in that: The steps include: 1) Data Collection The oxygen sensor collects the concentration data in the furnace body, and the pressure sensor collects the pressure data in the furnace body; the collected data are uploaded to the adaptive feedforward compensation module and the pressure gradient warning module of the control module respectively; 2) Emergency Response When the reading of any oxygen sensor is greater than 0.8%, the adaptive feedforward compensation module calculates the required nitrogen flow rate Q, opens the high-speed solenoid valve and the air pump, reaches the designed flow rate within 8ms, and the exhaust valve is synchronously opened to an opening angle of θ=0.65*Q; 3) Stress control strategies When the pressure gradient is greater than 0.03 MPa / m, the fuzzy PID controller calculates the pressure relief volume ΔP, and the servo motor drives the exhaust gas discharge valve to the target position with a full stroke time of ≤0.6s.

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