Automatic ignition control system and method capable of saving fuel gas

Abstract

The invention discloses an automatic ignition control system and method capable of saving fuel gas, and relates to the technical field of accident tail gas treatment in polycrystalline silicon production. The method comprises the steps that S1, tail gas channels are arranged in a graded mode, specifically, accident tail gas emptying airflow is guided to a second-stage or above diffusion channel; 2, incandescent light grading linkage control is conducted, specifically, incandescent light systems of two or more grades are arranged, the number of the incandescent light systems is consistent with the number of the grades of the diffusing channels, each grade of diffusing channel corresponds to one incandescent light, and instrument control valves are arranged on fuel gas pipelines of the incandescent lights and interlocked with pressure signals of an air inlet buffer tank; and S3, graded ignition triggering: when the pressure of the gas inlet buffer tank reaches a pressure threshold value of a corresponding grade, opening an instrument control valve of a fuel gas pipeline of an incandescent light of the corresponding grade in an interlocking manner, and simultaneously triggering a corresponding high-energy ignition gun to act, so that the fuel gas is ignited after entering the incandescent light. An automatic ignition system for silane accident tail gas has the problems of consumption of a large amount of ineffective fuel and high operation cost.

Description

Technical Field

[0001] This invention relates to the field of accident exhaust gas treatment technology in polysilicon production, specifically to an automatic ignition control system and method for saving fuel gas. Background Technology

[0002] In the silane production process, silane accident exhaust gases are flammable and explosive, requiring harmless treatment through incineration devices such as silane flares. The core requirement of the incineration device is to ensure that the exhaust gases are ignited promptly and completely during the release of accident exhaust gases, preventing the spread of unburned exhaust gases and the resulting hazards.

[0003] To meet the aforementioned ignition reliability requirements, traditional silane flare emergency exhaust gas incineration devices generally employ a continuous ignition system. This system is equipped with multiple igniters (i.e., continuous lamps), and all continuous lamps must maintain continuous combustion for 24 hours. This ensures a stable ignition source through continuous combustion of the continuous lamps, allowing the released emergency exhaust gas to immediately contact and ignite, eliminating incomplete combustion or safety hazards caused by delayed ignition.

[0004] However, in actual industrial production scenarios, the frequency of silane accident exhaust gas releases is extremely low: if the production process is precisely controlled and the equipment operates stably, the interval between exhaust gas releases can be as long as several months, or even several years. This means that the continuous burners in traditional units are in a state of "no exhaust gas to burn" most of the time, resulting in a large amount of ineffective fuel gas consumption. From the perspective of production cost, this problem is particularly prominent: the price of natural gas purchased by factories is usually 2-5 yuan / cubic meter, and for large silane combustion accident flares, the number of continuous burners is usually 5-10, with a single flare system having a fuel gas combustion capacity of approximately 5 cubic meters per cubic meter. 3 / h, with a maximum consumption of up to 50m³ 3 Based on this, the fuel cost per hour for the continuous lamp of a single flare is approximately 250 yuan; if calculated based on an annual operation of more than 8,000 hours, the annual cost of fuel consumption for the continuous lamp alone would reach 2 million yuan.

[0005] This traditional design not only wastes energy but also significantly increases production costs for enterprises, contradicting the current industrial trend of energy conservation, cost reduction, and efficiency improvement. Therefore, how to reduce the ineffective fuel consumption of the continuous lamps and lower operating costs while ensuring the reliability of ignition of the silane flare emergency exhaust gas has become a key technical problem that urgently needs to be solved in existing silane flare emergency exhaust gas incineration devices. Summary of the Invention

[0006] The purpose of this invention is to solve the problem of high operating costs and excessive waste fuel consumption in the automatic ignition system for silane accident tail gas during the existing silane production process.

[0007] This invention is achieved through the following technical solution: An automatic ignition control method for saving fuel gas includes the following steps: S1. Graded exhaust gas passage setting: The exhaust gas flow in case of an accident is guided to the second-level or higher venting passage. The diameter of the venting passage is set from small to large, and the exhaust gas volume handled by each venting passage increases with the increase of the pipe diameter. S2. Level-by-level linkage control of continuous light: Configure a continuous light system of 2 or more levels with the same number of levels as the venting channels, with one continuous light corresponding to each venting channel level; wherein, the continuous light corresponding to the first-level exhaust gas venting channel is kept in continuous combustion state; the fuel gas pipeline where the continuous light corresponding to the second-level and above venting channels is located is equipped with an instrument control valve, and the instrument control valve is interlocked with the pressure signal of the intake buffer tank. S3, Staged Ignition Trigger: When the intake buffer tank pressure reaches the secondary pressure threshold, the instrument control valve of the fuel gas pipeline where the secondary nightlight is located is interlocked and opened, and the corresponding high-energy ignition gun is triggered to ignite the fuel gas after it enters the secondary nightlight; when designed with more stages, when the intake buffer tank pressure reaches the next stage pressure threshold, the instrument control valve of the fuel gas pipeline where the corresponding stage nightlight is located is similarly interlocked and opened, and the corresponding high-energy ignition gun is triggered to complete the ignition.

[0008] Furthermore, a flame detection device is installed next to the igniter of each level of the permanent lamp. After the ignition action is completed, the flame signal is detected by the flame detection device to confirm successful ignition.

[0009] Furthermore, it also includes an ignition feedback confirmation step. After the ignition action is completed, the flame signal of the corresponding permanent lamp is detected by the flame detector. If the flame signal is detected, the ignition is determined to be successful; if the flame signal is not detected, the flame detector sends a signal to the system control unit, which then triggers the corresponding high-energy ignition gun action again.

[0010] Furthermore, in the aforementioned continuous lighting system, the fuel gas supply pipelines for each level of continuous lighting are independent of each other, and only the fuel gas supply pipeline for the first-level continuous lighting is kept constantly open.

[0011] Furthermore, the number of levels of the venting channel can be set to 3 to 5, and the control logic of the newly added level of the night light is the same as that of the second-level night light, and ignition is triggered by interlocking through the higher pressure threshold of the intake buffer tank.

[0012] Furthermore, the number of venting channels can be set to 3 levels, and the exhaust gas treatment capacity of the 3-level venting channels is specifically as follows: the first-level venting channel treats 100m³ of exhaust gas. 3 / h, secondary venting channel treatment 300m 3 / h, 600m of three-stage venting channel treatment 3 / h.

[0013] Furthermore, the fuel gas used for the continuous lighting is natural gas, and the total combustion volume of the fuel gas for each stage of the continuous lighting does not exceed 50m³. 3 / h.

[0014] A control system applicable to the aforementioned automatic ignition control method includes a DCS, an exhaust gas emission module, a night light control module, and a pressure interlock module. The exhaust gas venting module includes two or more venting channels. The diameter of the venting channels increases sequentially with the exhaust gas treatment capacity. The designed exhaust gas treatment capacity of each venting channel increases with the increase of the pipe diameter. The input end of each venting channel is connected to the main exhaust gas emission pipeline for silane flare accidents. The continuous light control module is configured with two or more continuous lights, which are the same as the number of venting channels. One continuous light is set at the exhaust outlet of each venting channel. The fuel gas supply pipeline where the continuous light of the first-level venting channel is located is kept open. Instrument control valves are connected in series on the fuel gas supply pipeline where the continuous light of the second-level and above venting channels is located. The pressure interlock module includes an intake buffer tank and a pressure sensor. The intake buffer tank is connected in series between the main exhaust pipe and the venting channel. The DCS is connected to the pressure sensor, the instrument control valve on the fuel gas supply pipeline where the emergency light is located, the instrument control valves on each level of the venting channel, and the high-energy ignition gun. The high-energy ignition gun corresponds to the emergency light, and the ignition end of the high-energy ignition gun faces the fuel gas outlet of the emergency light.

[0015] Furthermore, it also includes an ignition confirmation module: including a flame detection device, which corresponds one-to-one with the continuous light, and the detection end of the flame detection device is aligned with the flame area of ​​the continuous light; the flame detection device is connected to the DCS control, and the flame detection device uploads the detection signal to the DCS, and the DCS then controls the high-energy ignition gun to perform corresponding actions based on the signal analysis results. The flame detection device is an ultraviolet flame detection device or a sheathed thermocouple.

[0016] Furthermore, in the pressure interlock module, the secondary pressure threshold and the previous pressure threshold are set progressively, and the secondary pressure threshold is greater than the previous pressure alarm threshold. The pressure threshold can be set by the system control unit.

[0017] Furthermore, the instrument control valve is selected from one of the following: regulating valve, solenoid valve, pneumatic valve, and switching valve.

[0018] Compared with the prior art, the present invention has the following advantages and beneficial effects: I. This invention proposes a novel automatic ignition control method for saving fuel gas. By guiding emergency exhaust gas to two or more venting channels with increasing pipe diameter and processing capacity, it can adapt to exhaust gas with different emission volumes and avoid the problem of channel and flow mismatch. At the same time, only the first-stage automatic lamp burns continuously, while the second-stage and above automatic lamps are turned on and ignited as needed through pressure interlocking of the intake buffer tank, which greatly reduces unnecessary fuel gas consumption. Moreover, the entire process is automatically triggered without manual intervention, improving exhaust gas treatment efficiency and operational reliability, and reducing fuel costs.

[0019] Second, in this invention, a flame detection device is installed next to the igniter of each level of the continuous light. This device can detect the flame signal in real time after the ignition action is completed, and quickly and accurately confirm whether the ignition is successful. This effectively avoids the situation where exhaust gas is directly discharged without combustion due to ignition failure, eliminates the safety hazards caused by the direct discharge of flammable and explosive exhaust gas, and provides a direct basis for the system to judge the ignition status, thereby improving the overall operational safety.

[0020] Third, in this invention, through the ignition feedback confirmation step, when the flame detection device does not detect a flame signal, it can automatically send a signal to the system control unit (such as DCS), and the system will re-trigger the corresponding high-energy ignition gun action. Ignition can be achieved without manual intervention, which significantly improves the ignition success rate, reduces the ignition fault handling time, ensures that the lamp can continue to burn effectively during the exhaust gas emission period of an accident, and ensures the continuity and reliability of exhaust gas treatment.

[0021] Fourth, in this invention, the fuel gas supply pipelines for each level of the continuous light are independent of each other, which can prevent the failure of one level of pipeline from affecting the operation of other levels and improve the stability of system operation; at the same time, only the first level of continuous light pipeline is kept open, while the second level and above pipelines are closed under normal circumstances, reducing unnecessary fuel gas consumption from the pipeline supply source, further enhancing the fuel gas saving effect and reducing daily operating costs.

[0022] Fifth, in this invention, it is preferable to set the emission channel level to 3 to 5 levels, which can cover a wider range of exhaust gas emission flow scenarios from low to high, avoid the "gap" problem of only 2-level channels in the medium flow range, and improve the adaptability of operating conditions; and the control logic of the newly added level of the continuous light is consistent with that of the second level, so there is no need to redesign the complex control program, reduce the system development, debugging and maintenance costs, ensure the uniformity of control standards at all levels, and simplify the operation process.

[0023] VI. In this invention, based on actual production conditions, the number of venting channels is set to 3 levels. The specific exhaust gas treatment capacity of the 3-level venting channels is: 100m³ / s venting channel at level 1. 3 / h, secondary venting channel treatment 300m 3 / h, 600m of three-stage venting channel treatment 3 / h, in actual operation, the corresponding channel and the continuous light can be accurately matched according to the exhaust gas emission volume, which avoids fuel waste of using a large channel for small flow and prevents pressure overload of using a small channel for large flow, thus improving the economy and safety of operation.

[0024] VII. In this invention, the total combustion volume of fuel gas for each stage of the continuous lamp is limited to no more than 50m³. 3 The system strictly controls fuel gas consumption per hour, further reducing operating costs. At the same time, using natural gas as fuel ensures more complete combustion and produces fewer pollutants such as sulfides and particulate matter compared to other fuels, meeting environmental protection requirements and reducing environmental impact.

[0025] 8. In this invention, a preferred fuel-saving automatic ignition control method is proposed, which is applicable to the aforementioned control method. By coordinating the exhaust gas venting, the automatic warning light control, and the pressure interlocking module through a DCS, automatic ignition can be achieved without manual step-by-step operation, greatly improving the response speed and processing efficiency of emergency exhaust gas. Moreover, the venting channel and the automatic warning light correspond one-to-one, and the pressure interlocking module monitors the pressure of the intake buffer tank in real time to ensure accurate matching of "exhaust gas volume-channel-automatic warning light", avoiding exhaust gas accumulation or direct discharge. At the same time, the design of the module facilitates subsequent fault diagnosis and maintenance.

[0026] 9. In this invention, the flame detection device of the ignition confirmation module corresponds one-to-one with the continuous light, and can upload the flame detection signal to the DCS in real time. The DCS analyzes and determines whether the high-energy ignition gun needs to be re-triggered, forming a closed-loop control of "ignition-detection-feedback-adjustment". Compared with manual observation, it is more accurate and timely, and effectively avoids loss of control of the ignition state. At the same time, this module adds safety redundancy to the system, can quickly detect ignition abnormalities (such as flame extinguishing) and deal with them in time, and prevent exhaust gas safety and environmental risks caused by ignition failure. The flame detection device can be selected as an ultraviolet flame detection device or a sheathed thermocouple according to the needs.

[0027] 10. In this invention, the secondary pressure threshold is higher than the upper-level pressure alarm threshold and is set progressively, which can effectively prevent the accidental activation of the constant-on lights at each level due to small pressure fluctuations, reduce unnecessary fuel consumption, and improve control accuracy. At the same time, the pressure threshold can be flexibly set by the system control unit, which can adapt to different production conditions (such as the exhaust gas emissions of different production lines and the environmental pressure of different seasons) without modifying the hardware, reducing system adaptation costs and enhancing operating condition flexibility. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the fuel-saving automatic ignition control system of the present invention.

[0029] The components include: 1. DCS; 2. Primary venting channel; 3. Secondary venting channel; 4. Tertiary venting channel; 5. Primary automatic light; 6. Secondary automatic light; 7. Tertiary automatic light; 8. Switch valve I; 9. Switch valve II; 10. Switch valve III; 11. Switch valve IV; 12. Exhaust gas emission main pipe; 13. Intake buffer tank; 14. Pressure sensor; 15. Fuel gas pipeline; 16. Flow sensor; 17. High-energy ignition gun I; 18. High-energy ignition gun II; 19. High-energy ignition gun III; 20. Flame detection device; 21. Combustion tower. Detailed Implementation

[0030] The present invention will be further described in detail below with reference to embodiments, but the implementation of the present invention is not limited thereto.

[0031] Example 1 In this embodiment, an automatic ignition control system that saves fuel gas is used as an example to further illustrate this solution.

[0032] refer to Figure 1 The system includes DCS1, exhaust gas venting module, continuous light control module and pressure interlock module. In this embodiment, the instrument control valves are all on / off valves, which can meet production needs and are also relatively cheaper.

[0033] The exhaust gas venting module includes two or more venting channels. The diameter of the venting channels increases sequentially with the exhaust gas treatment capacity. The designed exhaust gas treatment capacity of each venting channel increases with the increase of the pipe diameter. The input end of each venting channel is connected to the main exhaust gas emission pipeline for silane flare accidents. Figure 1 The diagram illustrates a system connection with three venting channels, namely, a primary venting channel 2, a secondary venting channel 3, and a tertiary venting channel 4. Switch valve I 8 and switch valve II 9 are respectively installed on the secondary venting channel 3 and the tertiary venting channel 4.

[0034] The continuous light control module is configured with two or more continuous lights, matching the number of venting channel levels, with one continuous light corresponding to the exhaust outlet of each venting channel level. Figure 1 The diagram illustrates a three-stage emergency light system, consisting of a primary emergency light (5), a secondary emergency light (6), and a tertiary emergency light (7). The fuel gas supply line for the primary venting channel 2 remains continuously open, while the fuel gas supply lines for the secondary and higher venting channels are all equipped with a series of on / off valves (e.g., ...). Figure 1 (Switching valves Ⅲ10 and Ⅳ11). The pressure interlock module includes an intake buffer tank 13 and a pressure sensor 14. The intake buffer tank 13 is connected in series between the exhaust gas main pipe 12 and the venting channel. The DCS1 is connected to the pressure sensor 14, the corresponding switch valves (switch valve III 10 and switch valve IV 11) on the fuel gas pipe 15 where the night lamp is located, the switch valves (switch valve I 8 and switch valve II 9) on the secondary and above venting channels, and each high-energy ignition gun. The high-energy ignition gun corresponds to the night lamp, and the ignition end of the high-energy ignition gun faces the fuel gas outlet of the night lamp.

[0035] Based on the above control system, the automatic ignition control method for saving fuel gas includes the following steps: Step 1: Graded setting of exhaust gas channels: The exhaust gas flow in case of an accident is guided to the second-level or higher venting channel. The diameter of the venting channel is set from small to large, and the exhaust gas volume handled by each venting channel increases with the increase of the pipe diameter. Step 2, Level-by-level linkage control of the continuous light: Configure a continuous light system of 2 levels or more, which is consistent with the number of levels of the venting channels, with one continuous light corresponding to each level of the venting channel; wherein, the continuous light corresponding to the first-level exhaust gas venting channel keeps in a continuous combustion state; the fuel gas pipeline 15 of the continuous light corresponding to the second-level and above venting channels is equipped with a switch valve, and the switch valve is interlocked with the pressure signal of the intake buffer tank 13. Step 3, Staged Ignition Trigger: When the pressure in the intake buffer tank 13 reaches the secondary pressure threshold, the valve of the fuel gas pipeline 15 connected to the secondary lamp 6 is interlocked and opened, and the corresponding high-energy ignition gun is triggered to ignite the fuel gas after it enters the secondary lamp 6. When the design is multi-stage, when the pressure in the intake buffer tank 13 reaches the next stage pressure threshold, the valve of the fuel gas pipeline 15 of the corresponding stage lamp is interlocked and opened, and the corresponding high-energy ignition gun is triggered to complete the ignition, ensuring that the exhaust gas in the combustion tower 21 is completely burned.

[0036] Example 2 This embodiment is a further optimization of embodiment 1, the difference being that the control system also includes an ignition confirmation module: including a flame detector 20, see reference. Figure 1 Each flame detector 20 corresponds to a continuous lamp, with its detection end aligned with the flame area of ​​the lamp. The flame detector 20 is connected to the DCS1 control system, transmitting its detection signal to the DCS1. The DCS1 then controls the high-energy ignition gun to perform the corresponding action based on the signal analysis results. After ignition, the flame signal is detected by the flame detector 20 to confirm successful ignition. The flame detector can be either an ultraviolet flame detector or a sheathed thermocouple, depending on the requirements.

[0037] Compared with Embodiment 1, this embodiment also includes an ignition feedback confirmation step. After the ignition action is completed, the flame signal of the corresponding permanent lamp is detected by the flame detector 20. If the flame signal is detected, the ignition is determined to be successful. If the flame signal is not detected, the flame detector 20 sends a signal to the system control unit, and the system control unit re-triggers the corresponding high-energy ignition gun action.

[0038] Example 3 Compared with Examples 1 and 2, the difference in this embodiment is that in the continuous light system, the fuel gas supply pipelines of each level of continuous light are independent of each other, and only the fuel gas supply pipeline of the first-level continuous light 5 is kept open.

[0039] Example 4 Compared with embodiments 1 to 3, the difference in this embodiment is that the number of levels of the venting channel can be set to 3 to 5, and the control logic of the newly added level of the continuous light is the same as that of the second-level continuous light 6, and the ignition is triggered by interlocking through the higher pressure threshold of the intake buffer tank 13.

[0040] Example 5 Compared with Examples 1-4, the difference in this embodiment is that the number of venting channels can be set to 3. The exhaust gas treatment capacity of the 3-stage venting channels is specifically as follows: the first-stage venting channel 2 treats 100m³ of exhaust gas. 3 / h, secondary venting channel 3 processes 300m 3 / h, Level 3 venting channel 4 treatment 600m 3 / h.

[0041] Example 6 The difference between this embodiment and embodiments 1-5 is that the fuel gas used for the continuous lamp is natural gas, and the total combustion volume of the fuel gas for each stage of the continuous lamp does not exceed 50m³. 3 / h.

[0042] Example 7 To facilitate public understanding of the present invention, this embodiment uses a control system of a preferred automatic ignition control method as an example to further illustrate the solution. This control system can be used to handle silane flare accident exhaust gas treatment scenarios during the production of rod-shaped and granular polycrystalline silicon.

[0043] Taking the production of granular polycrystalline silicon as an example, the flammable and explosive tail gas emitted by the silane production unit (mainly containing silane, hydrogen and other components) can be safely released and efficiently utilized by the control system.

[0044] The control system of this automatic ignition control method is referenced. Figure 1It includes DCS1, exhaust gas venting module, night light control module, pressure interlock module, and ignition confirmation module. In this embodiment, all instrument control valves are on / off valves, which meet production requirements while also being relatively cheaper.

[0045] The exhaust gas venting module includes three venting channels (including primary venting channel 2, secondary venting channel 3, and tertiary venting channel 4). The pipe diameter of the venting channels increases sequentially with the exhaust gas treatment capacity, and the designed exhaust gas treatment capacity of each venting channel increases with the increase of the pipe diameter. The input end of each venting channel is connected to the main exhaust gas emission pipeline for silane flare accidents. The secondary venting channel 3 and the tertiary venting channel 4 are respectively equipped with switch valve I8 and switch valve II9.

[0046] The continuous light control module is configured with three levels of continuous lights, matching the number of levels in the venting channels. Each venting channel has one continuous light at its exhaust outlet (corresponding to first-level continuous light 5, second-level continuous light 6, and third-level continuous light 7, respectively). The fuel gas supply pipeline for the continuous light in the first-level venting channel 2 is kept in a normally open state. Switch valves III10 and IV11 are connected in series on the fuel gas supply pipelines where the continuous lights in the second-level venting channel 3 and the third-level venting channel 4 are located.

[0047] The pressure interlock module includes an intake buffer tank 13 and a pressure sensor 14. The intake buffer tank 13 is connected in series between the exhaust main pipe 12 and the venting channel. The DCS1 is connected to the pressure sensor 14, the switching valves I and II on the secondary venting channel 3 and the tertiary venting channel 4, the corresponding switching valves III10 and IV11 on the fuel gas pipe 15 where the night lamp is located, and the high-energy ignition guns I17, II18 and III19. Each high-energy ignition gun corresponds to a night lamp, and the ignition end of the high-energy ignition gun faces the fuel gas outlet of the night lamp.

[0048] In the pressure interlock module, the secondary pressure threshold and the previous pressure threshold are set progressively, and the secondary pressure threshold is greater than the previous pressure alarm threshold. The pressure threshold can be set by the system control unit.

[0049] The ignition confirmation module includes a flame detection device 20. In this embodiment, the flame detection device 20 is a sheathed thermocouple. The flame detection device 20 corresponds one-to-one with the continuous light, and the detection end of the flame detection device 20 is aligned with the flame area of ​​the continuous light. The flame detection device 20 is connected to the DCS1 control system. The flame detection device 20 uploads the detection signal to the DCS1, and the DCS1 then controls the high-energy ignition gun to perform corresponding actions based on the signal analysis results.

[0050] Basic parameter settings for the control system.

[0051] The venting channel is configured with a three-stage venting channel, and the pipe diameter and exhaust gas treatment capacity of each stage are matched as follows: Primary venting channel 2: Pipe diameter (DN) is 100, designed exhaust gas treatment capacity is 100m³. 3 / h, connected in parallel to the outlet of the intake buffer tank 13 (connected to the exhaust gas main pipe 12).

[0052] Secondary venting channel 3: Pipe diameter (DN) is 200, designed exhaust gas treatment capacity is 300m³. 3 / h, connected in parallel to the outlet of the intake buffer tank 13 (connected to the exhaust gas main pipe 12).

[0053] Stage 3 venting channel 4: Pipe diameter (DN) is 300, designed exhaust gas treatment capacity is 600m³. 3 / h, connected in parallel to the outlet of the intake buffer tank 13 (connected to the exhaust gas main pipe 12).

[0054] All venting channel inlets are connected to the main silane flare emergency exhaust gas emission pipeline (DN400) via inlet buffer tank 13 (20m³). 3 Connect the exhaust gas to ensure that the pressure is stabilized before it is released in separate channels.

[0055] The continuous lighting control system is equipped with three levels of continuous lights (each corresponding to a venting channel), and all fuel gas is natural gas. Specific parameters are as follows: Level 5 automatic light: The fuel gas supply pipeline (DN20) is kept constantly open, and the combustion rate is stable at 10m³. 3 / h, installed directly below the exhaust gas outlet of the first-stage venting channel 2 (ensure the flame covers the exhaust gas outlet). Secondary automatic light 6: Fuel gas supply pipeline (DN25) connected in series with switch valve Ⅲ10, combustion capacity 15m³ 3 / h, installed directly below the exhaust gas outlet of the secondary venting channel 3; Level 3 continuous light 7: Fuel gas supply pipeline (DN32) connected in series with switch valve IV11, combustion capacity 20m³ 3 / h, installed directly below the exhaust gas outlet of the third-stage venting channel 4; The total fuel gas combustion volume of the three-stage continuous lamp is 45m³. 3 / h.

[0056] Pressure interlock parameters: A pressure sensor 14 is installed on the intake buffer tank 13 and communicates with DCS1. The pressure threshold is set as follows: Level 1 pressure alarm threshold: ≤10kPa (which can be met by using a Level 1 venting channel); Secondary ignition trigger threshold: 10kPa<P≤20kPa (greater than the primary alarm threshold, triggering the secondary continuous light 6); Level 3 ignition trigger threshold: >20kPa (greater than the Level 2 trigger threshold, triggering Level 3 continuous light 7); All thresholds can be directly modified through the DCS1 operating interface to adapt to fluctuations in exhaust emissions under different production conditions.

[0057] Ignition and confirmation module configuration.

[0058] High-energy ignition gun: one gun for each level of continuous lamp, with the ignition end 50mm from the fuel gas outlet of the continuous lamp to ensure a high ignition success rate; Flame detection device 20: One device for each level of continuous lamp, with the detection end aligned with the core area of ​​the flame of the continuous lamp, and a response time ≤0.1s; The flame detection device 20 is interlocked with DCS1: If no flame signal is detected within 5 seconds after ignition, DCS1 will automatically re-trigger the corresponding high-energy ignition gun (up to 2 times). If it still fails, an audible and visual alarm will be issued to prompt manual inspection.

[0059] The automatic ignition control method for saving fuel gas based on the above-mentioned automatic ignition control method includes the following steps: Step 1, Staged setting of exhaust gas passage: The exhaust gas venting flow in case of an accident is guided to the third stage venting passage. The diameter of the venting passage is set sequentially from small to large, and the exhaust gas volume handled by the third stage venting passage increases with the increase of the pipe diameter. The control logic of the third stage warning light 7 is the same as that of the second stage warning light 6, and ignition is triggered by interlocking through the higher pressure threshold of the intake buffer tank 13.

[0060] Step 2, Level-by-level linkage control of the continuous light: Configure a 3-level continuous light system with the same number of levels as the venting channels, with one continuous light corresponding to each venting channel level; wherein, the continuous light corresponding to the first-level exhaust gas venting channel keeps in a continuous combustion state; the fuel gas pipelines 15 where the continuous lights corresponding to the second-level venting channel 3 and the third-level venting channel 4 are located are respectively equipped with switch valve I8 and switch valve II9, and the switch valve I8 and switch valve II9 are both interlocked with the pressure sensor 14 on the intake buffer tank 13.

[0061] In this step, the fuel gas supply lines for each stage of the automatic lamp are independent of each other, and only the fuel gas supply line for the first-stage automatic lamp 5 remains continuously open. A flow sensor 16 for detecting the flow rate of fuel gas in the pipeline is installed on the fuel gas pipeline 15.

[0062] Step 3, Staged Ignition Trigger: When the pressure in the intake buffer tank 13 reaches the secondary pressure threshold, the interlock valve I8 of the fuel gas pipeline 15 where the secondary permanent light 6 is located is opened, and the corresponding high-energy ignition gun I17 is triggered to activate, so that the fuel gas enters the secondary permanent light 6 and is ignited; when the pressure in the intake buffer tank 13 reaches the tertiary pressure threshold, the interlock valve II9 of the fuel gas pipeline 15 where the tertiary permanent light 7 is located is opened, and the corresponding high-energy ignition gun II18 is triggered to complete the ignition.

[0063] Step 4: Ignition Feedback Confirmation: After the ignition action is completed, the flame signal of the corresponding permanent light is detected by the flame detector 20. If the flame signal is detected, the ignition is determined to be successful; if the flame signal is not detected, the flame detector 20 sends a signal to the system control unit, which then triggers the corresponding high-energy ignition gun action again.

[0064] More specifically: 1. Initial state (low exhaust emissions).

[0065] When the silane production unit only produces a small amount of accidental exhaust gas (e.g., 80m³), 3 When the exhaust gas reaches 0.005 MPa (below the first-level alarm threshold of 0.01 MPa), the exhaust gas enters the intake buffer tank 13 through the main pipeline, and the pressure inside the tank stabilizes at 0.005 MPa. Only the primary venting channel 2 is open (exhaust gas treatment capacity matched to 80m³). 3 / h), the first-level continuous lamp 5 is kept burning (fuel gas 10m 3 / h), ensuring the safe release of exhaust gas after combustion; When the secondary and tertiary venting channels 4 are closed, the corresponding fuel gas switch valves I8 and II9 for the continuous light are also closed, and there is no fuel gas consumption in the secondary and tertiary venting channels 4.

[0066] 2. Secondary night light triggers 6 times (medium exhaust emissions).

[0067] When the equipment malfunction worsened, the exhaust emissions increased to 320m³. 3 At a rate of / h, the pressure in intake buffer tank 13 rises to 0.015MPa (reaching the secondary trigger threshold): DCS1 receives the signal from pressure sensor 14 and immediately controls the opening of valve I8 on the secondary automatic light 6 and fuel gas pipeline 15, allowing natural gas to flow at a rate of 15m³ / min. 3 / h of flow enters the secondary continuous light 6; Simultaneously trigger the corresponding high-energy ignition gun I17 action, and complete ignition within 1 second; The flame detector 20 detects the flame signal of the secondary lamp 6 and uploads the "ignition successful" signal to the DCS1. The DCS1 records the status and maintains the operation of the secondary lamp 6. Secondary venting channel 3 is activated, working together with primary venting channel 2 to process 320m³ of wastewater. 3 / h exhaust gas (total treatment capacity 400m3 / h, matching emission volume).

[0068] 3. Level 3 continuous light triggers (high exhaust emissions).

[0069] When the device malfunctions, the exhaust emissions increase to 580m³. 3 At / h, the pressure in intake buffer tank 13 rises to 0.05MPa (reaching the level 3 trigger threshold): DCS1 activates the switch valve II9 on fuel gas pipeline 15, which is the third-level continuous light 7, allowing natural gas to flow at a rate of 20m³ / h. 3 / h flow enters the level 3 continuous light 7, and at the same time triggers the corresponding high-energy ignition gun II 18 to complete the ignition; After the flame detector 20 detects the level 3 flame signal, it sends a "successful ignition" message to the DCS1, and the level 3 venting channel 4 is opened. The tertiary channel works in conjunction with the primary and secondary channels, achieving a total exhaust gas treatment capacity of 1000m³. 3 / h, fully covering 580m 3 The emissions are per hour, and the total fuel gas consumption for each stage of the continuous lighting is 45m³. 3 / h, no waste.

[0070] 4. Troubleshooting (ignition failure scenario).

[0071] If the flame detector 20 corresponding to the three-stage automatic lamp 7 does not detect a flame within 5 seconds after ignition: The flame detector 20 corresponding to the three-level continuous lamp 7 sends an "ignition failure" signal to the DCS1. DCS1 automatically re-triggers high-energy ignition gun III 19 (second ignition); If no flame is detected the second time, DCS1 will issue an audible and visual alarm for "ignition failure" and simultaneously close the switch valve IV11 on the fuel gas pipeline where the third-level continuous light 7 is located (to prevent fuel gas leakage), while keeping the first and second-level channels running (to temporarily handle exhaust gas) and waiting for manual troubleshooting (such as carbon buildup on the ignition gun electrodes, insufficient fuel gas pressure, etc.).

[0072] The fuel-saving automatic ignition control system and method described in this embodiment, compared to the traditional scheme (total combustion capacity 45m³), offers advantages over traditional methods. 3 (continuous consumption / h), in this embodiment, only 10m is consumed at low flow rates. 3 / h, consuming 25m at medium flow rates 3 / h, consuming 45m at high flow rates 3The system reduces average fuel gas consumption by approximately 60% per hour, resulting in annual natural gas cost savings exceeding 1.5 million yuan. Simultaneously, through a closed-loop control system of "pressure interlock-ignition-flame confirmation," there is no direct emission of exhaust gas due to ignition failure. Flammable and explosive gases such as silanes are converted into harmless SiO2 and H2O after combustion, meeting environmental and safety standards. This fuel-saving automatic ignition control system and method can cover an area of ​​80-600 meters. 3 The system can handle exhaust emission fluctuations of / h without requiring manual channel switching or adjustment of the automatic lights, resulting in a high degree of automation and reduced human error.

[0073] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications or equivalent changes made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. An automatic ignition control method for saving fuel gas, characterized in that, Includes the following steps: S1. Graded exhaust gas passage setting: The exhaust gas flow in case of an accident is guided to the second-level or higher venting passage. The diameter of the venting passage is set from small to large, and the exhaust gas volume handled by each venting passage increases with the increase of the pipe diameter. S2. Level-by-level linkage control of continuous light: Configure a continuous light system of 2 or more levels with the same number of levels as the venting channels, with one continuous light corresponding to each venting channel level; wherein, the continuous light corresponding to the first-level exhaust gas venting channel is kept in continuous combustion state; the fuel gas pipeline where the continuous light corresponding to the second-level and above venting channels is located is equipped with an instrument control valve, and the instrument control valve is interlocked with the pressure signal of the intake buffer tank. S3, Staged Ignition Trigger: When the intake buffer tank pressure reaches the secondary pressure threshold, the instrument control valve of the fuel gas pipeline where the secondary nightlight is located is interlocked and opened, and the corresponding high-energy ignition gun is triggered to ignite the fuel gas after it enters the secondary nightlight; when designed with more stages, when the intake buffer tank pressure reaches the next stage pressure threshold, the instrument control valve of the fuel gas pipeline where the corresponding stage nightlight is located is similarly interlocked and opened, and the corresponding high-energy ignition gun is triggered to complete the ignition.

2. The automatic ignition control method for saving fuel gas according to claim 1, characterized in that: A flame detection device is installed next to the igniter of each level of the permanent lamp. After the ignition action is completed, the flame signal is detected by the flame detection device to confirm that the ignition was successful.

3. The automatic ignition control method for saving fuel gas according to claim 2, characterized in that: It also includes an ignition feedback confirmation step. After the ignition action is completed, the flame signal of the corresponding permanent lamp is detected by the flame detection device. If the flame signal is detected, the ignition is determined to be successful. If the flame signal is not detected, the flame detection device sends a signal to the system control unit, which then triggers the corresponding high-energy ignition gun action again.

4. The automatic ignition control method for saving fuel gas according to claim 1, characterized in that: In the continuous lighting system, the fuel gas supply pipelines for each level of continuous lighting are independent of each other, and only the fuel gas supply pipeline for the first level of continuous lighting remains open.

5. The automatic ignition control method for saving fuel gas according to claim 1, characterized in that: The number of levels of the venting channel can be set to 3 to 5, and the control logic of the newly added level of the continuous light is the same as that of the second-level continuous light, and ignition is triggered by interlocking the higher pressure threshold of the intake buffer tank.

6. The automatic ignition control method for saving fuel gas according to claim 5, characterized in that: The number of venting channels is set to 3 levels. The exhaust gas treatment capacity of the 3-level venting channels is as follows: the first-level venting channel treats 100m³ of exhaust gas. 3 / h, secondary venting channel treatment 300m 3 / h, 600m of three-stage venting channel treatment 3 / h.

7. The automatic ignition control method for saving fuel gas according to claim 1, characterized in that: The fuel gas used for the continuous lighting is natural gas, and the total combustion volume of the fuel gas for each stage of the continuous lighting does not exceed 50m³. 3 / h.

8. A control system applicable to the fuel-saving automatic ignition control method as described in claim 1, characterized in that, Includes DCS, exhaust gas emission module, emergency light control module, and pressure interlock module. The exhaust gas venting module includes two or more venting channels. The diameter of the venting channels increases sequentially with the exhaust gas treatment capacity. The designed exhaust gas treatment capacity of each venting channel increases with the increase of the pipe diameter. The input end of each venting channel is connected to the main exhaust gas emission pipeline for silane flare accidents. The continuous light control module is configured with 3 or more continuous lights, which is consistent with the number of venting channels. One continuous light is set at the exhaust outlet of each venting channel. The fuel gas supply pipeline where the continuous light of the first-level venting channel is located is kept in a normally open state. Instrument control valves are connected in series on the fuel gas supply pipeline where the continuous light of the second-level and above venting channels is located. The pressure interlock module includes an intake buffer tank and a pressure sensor. The intake buffer tank is connected in series between the main exhaust pipe and the venting channel. The DCS is connected to the pressure sensor, the instrument control valve on the fuel gas supply pipeline where the emergency light is located, the instrument control valves on each level of the venting channel, and the high-energy ignition gun. The high-energy ignition gun corresponds to the emergency light, and the ignition end of the high-energy ignition gun faces the fuel gas outlet of the emergency light.

9. The control system according to claim 1, characterized in that, It also includes an ignition confirmation module: including a flame detector, which corresponds one-to-one with the continuous light, and the detection end of the flame detector is aligned with the flame area of ​​the continuous light; the flame detector is connected to the DCS control, and the flame detector uploads the detection signal to the DCS, and the DCS then controls the high-energy ignition gun to perform corresponding actions based on the signal analysis results. The flame detection device is an ultraviolet flame detection device or a sheathed thermocouple.

10. The control system according to claim 1, characterized in that: In the pressure interlock module, the secondary pressure threshold and the previous pressure threshold are set progressively, and the secondary pressure threshold is greater than the previous pressure alarm threshold. The pressure threshold can be set by the system control unit.

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