Laser direct ignition device for releasing torch and control method of laser direct ignition device

Abstract

The invention relates to the technical field of industrial waste gas treatment safety equipment, discloses a laser direct ignition device for a release torch and a control method of the laser direct ignition device, and aims to solve the problems of low ignition reliability, dependence on auxiliary fuel and high maintenance cost in the prior art. High-temperature plasma fire cores are directly generated in flare gas flow through high-energy pulse laser, reliable ignition of main flare gas is achieved, and guiding flames and a fuel supply system matched with the guiding flames are thoroughly omitted; comprising a laser generator, a light beam transmission and focusing system, a lens protection and cooling system, a state monitoring unit and an intelligent control system, the laser generator is connected with the intelligent control system through a cable and provides an ignition energy source for the torch head. The light beam transmitting and focusing system is connected with the laser generator, ignition laser generated by the laser generator acts on a torch head to conduct torch gas laser ignition, and the lens protecting and cooling system is used for guaranteeing long-time stable operation of the laser generator and the light beam transmitting and focusing system.

Description

Technical Field

[0001] This invention relates to the field of industrial waste gas treatment safety equipment technology, specifically, to a laser direct ignition device and its control method for an venting torch. Background Technology

[0002] A flare (mainly including the flare head, flare tube, flare support facilities, venting air, and venting pipelines) is a crucial safety and environmental protection facility in petroleum refining, chemical production, and oil and gas extraction. Its core function is to promptly and safely burn off flammable gases that cannot or are not suitable for recovery during plant start-up and shutdown, emergency situations, or normal fluctuations, preventing the accumulation of flammable gases into explosive mixtures, while simultaneously converting toxic and harmful gases (such as H2S) into less hazardous substances. A reliable ignition system is the core of safe flare operation. For remote monitoring, a host computer connected to the flare is generally also installed.

[0003] The existing ignition methods mainly include the following: 1. High-altitude igniter (always-on lamp): It needs to maintain a small flame for a long time, consumes a lot of fuel gas, has high operating costs, and is prone to extinguishing in severe weather such as strong winds and heavy rain.

[0004] 2. High-voltage spark ignition: A small torch is ignited by a high-voltage electric arc, which then ignites the main torch. However, the arc energy is limited, and the electrodes are prone to carbon buildup, oxidation, and coking, leading to decreased ignition reliability, especially under humid, hydrocarbon-rich, or low-oxygen conditions where the failure rate is higher.

[0005] 3. High-frequency induction heating ignition: A small torch is ignited by heating a conductor with a high-frequency induction coil, which then ignites the main torch. However, its energy is limited, and the heated conductor oxidizes and becomes brittle, leading to decreased ignition reliability, especially under rainy, humid, hydrocarbon-rich, or low-oxygen conditions with a higher failure rate.

[0006] 4. Flame Front Ignition (FFG): Requires the laying of closed fuel gas pipelines, which poses risks of leakage and explosion, and the system is complex.

[0007] In recent years, laser-induced spark ignition has emerged, but most methods still use it to ignite a small pilot flame (guided ignition), which then ignites the main flare gas. This method fails to fundamentally eliminate the auxiliary fuel system and has a complex structure. Directly using laser energy to ignite the main flare gas places extremely high demands on the laser's energy, pulse characteristics, focal point position, and its linkage with the control system; existing technologies do not yet offer mature and reliable solutions.

[0008] Therefore, it is particularly important to develop a laser direct ignition device and control method that can directly ignite the main flare gas, requires no guiding flame, adapts to harsh working conditions, and is highly automated. Summary of the Invention

[0009] The purpose of this invention is to design a laser direct ignition device and its control method for a flare torch. On one hand, it provides a laser direct ignition device for a flare torch; on the other hand, it provides a control method for the laser direct ignition device, to solve the problems of low ignition reliability, reliance on auxiliary fuel, and high maintenance costs in existing technologies. This invention directly generates a high-temperature plasma flame core in the flare gas flow using a high-energy pulsed laser, achieving reliable ignition of the main flare gas and completely eliminating the need for a pilot flame and its associated fuel supply system.

[0010] This invention is achieved through the following technical solution: a laser direct ignition device for an empty torch, comprising a laser generator, a beam transmission and focusing system, a lens protection and cooling system, a status monitoring unit, and an intelligent control system. The laser generator is connected to the intelligent control system via a cable. The beam transmission and focusing system is connected to the laser generator and is used to apply the ignition laser generated by the laser generator to the torch head for laser ignition. The intelligent control system is connected to the laser generator, the lens protection and cooling system, and the status monitoring unit. The beam transmission and focusing system and the lens protection and cooling system are connected, and the lens protection and cooling system is connected to the laser generator.

[0011] To further improve the realization of the laser direct ignition device for venting torches described in this invention, the following structure is specifically adopted: the beam transmission and focusing system includes a transmission fiber and a remote focusing head. The remote focusing head is located 2 to 5 meters below the torch head, and the axis of the light outlet of the remote focusing head forms an angle of 30° to 60° with the direction of torch airflow. The remote focusing head is connected to the laser generator through the transmission fiber, and the lens protection and cooling system is connected to the remote focusing head.

[0012] To further improve the realization of the laser direct ignition device for flare torches described in this invention, the following structure is specifically adopted: the transmission optical fiber is an armored quartz optical fiber.

[0013] To further improve the realization of the laser direct ignition device for venting torches described in this invention, the following structure is specifically adopted: the lens protection and cooling system is provided with a purging unit, a circulating cooling unit, and a fan. The purging unit is connected to a remote focusing head via a pipe, and the circulating cooling unit is connected to the laser generator and the remote focusing head via pipes respectively. The intelligent control system controls the self-control valve A connected to the purging unit, the self-control valve B of the circulating cooling unit, and the fan. The fan is connected to both the purging unit and the circulating cooling unit.

[0014] To further improve the realization of the laser direct ignition device for a venting torch described in this invention, the following structure is specifically adopted: the status monitoring unit is equipped with a flame detection module, a venting air detection module, and a laser energy detection module. The flame detection module is connected to the intelligent control system via a control cable and is used to detect successful ignition and the torch combustion status. The venting air detection module is installed on the venting pipeline and is connected to the intelligent control system via a control cable for detecting venting air emissions. The laser energy detection module is built into the laser generator and is connected to the intelligent control system via a control cable for monitoring the energy and power of the output laser, providing data for the self-diagnosis of the intelligent control system.

[0015] To further improve the realization of the laser direct ignition device for venting torches described in this invention, the following structure is specifically adopted: the flame detection module adopts an ultraviolet flame detector or a sheathed thermocouple, and the venting detection module adopts a flow switch, a pressure switch, a pressure transmitter, or an online chromatographic analyzer.

[0016] To further improve the realization of the laser direct ignition device for flare torches described in this invention, the following configuration is specifically adopted: the laser generator is a pulsed Nd:YAG laser or a fiber laser, and the intelligent control system is a PLC control system.

[0017] To further improve the realization of the laser direct ignition device for flare torches described in this invention, the following configuration structure is adopted: it also includes a power supply connected to the intelligent control system.

[0018] A control method for a laser direct ignition device, based on the aforementioned laser direct ignition device for venting a torch, includes the following steps: 1) System standby and self-test: After the laser direct ignition device is powered on, the intelligent control system starts, the fan starts working, the circulating cooling unit starts working, and the purging unit runs continuously for 10~30 seconds (preferably 10 seconds); the intelligent control system performs a self-test and verifies the reading of the laser energy detection module; 2) Ignition Trigger: The intelligent control system receives ignition trigger signals in real time from the host computer or from the venting detection module installed on the flare tube inlet pipeline (venting pipeline) for detecting venting. When the value of the venting detection module exceeds the preset safety threshold, it is determined that ignition is required and immediately proceeds to step 3). Ignition sequence: 3) Pre-purge and focus positioning: Increase the purge gas flow rate of the purge unit (e.g., for 5-10 seconds, preferably 10 seconds) to ensure the cleanliness of the focusing lens of the remote focusing head; at the same time, based on the preset torch gas parameter estimation model, the intelligent control system can fine-tune the position of the laser focusing point (by controlling the adjustable focusing lens group (focusing lens composition) in the remote focusing head or selecting lenses with different focal lengths) so that the remote focusing head is always in the optimal ignition area. 4) Laser Emission and Direct Ignition: The intelligent control system sends a trigger command to the laser generator, which emits an ignition laser. This laser is transmitted via optical fiber to a remote focusing head, which repeatedly punctures the air at a preset focal point, forming multiple stable plasma fire nuclei that directly ignite the flowing flare gas. In other words, the laser generator emits a series of high-energy pulsed lasers at a specific frequency (e.g., 1-5 Hz). After transmission and focusing, the high-energy pulsed lasers repeatedly puncture the air at the preset focal point, forming multiple stable plasma fire nuclei that directly ignite the flowing flare gas. 5) Flame Confirmation: The flame detection module continuously monitors after laser emission (e.g., within 3-5 seconds, preferably 5 seconds). If a stable flame signal is detected, the ignition is determined to be successful. The intelligent control system controls the laser generator to stop laser emission, stops the fan, and closes the self-control valve A of the purging unit and the self-control valve B of the circulating cooling unit. It also sends an ignition success signal to the host computer. 6) Retry and Alarm: If the flame detection module does not detect a flame within a preset time (e.g., 10-20 seconds, preferably 20 seconds), the ignition is deemed to have failed. The intelligent control system can automatically start the retry program (up to 3 times). Before each retry, a post-purge time (5-10 seconds, preferably 5 seconds) is added. If multiple retry attempts fail, laser emission is stopped. The installed audible and visual alarm can also be activated to trigger an alarm and generate a fault report (e.g., "insufficient laser energy", "lens contamination", "no gas").

[0019] To further improve the control method of the laser direct ignition device described in this invention, the following setting is specifically adopted: flameout protection: during torch combustion, if the flame detection module detects flameout, the intelligent control system immediately and unconditionally re-executes steps 4) to 6) until ignition is successful or laser emission stops, ensuring safety.

[0020] Compared with the prior art, the present invention has the following advantages and beneficial effects: This invention achieves true direct ignition: it requires no pilot flame or auxiliary fuel gas, simplifies the system structure, completely eliminates the safety risks caused by the extinguishing of the pilot flame, and has extremely low operating costs.

[0021] This invention has extremely high ignition reliability: the energy density of the high-energy laser plasma ignition core is much higher than that of traditional sparks, it has strong anti-interference ability, can work reliably in severe weather conditions such as strong winds and heavy rain, and has a high success rate.

[0022] This invention boasts ultra-low maintenance costs: the main energy equipment is placed on the ground, the optical head is well protected, and there are no easily damaged consumable parts, greatly reducing the frequency and cost of maintenance.

[0023] This invention features intelligence and adaptability: the intelligent control system has self-diagnosis and adaptive adjustment capabilities, can fine-tune the ignition strategy according to the operating conditions, and quickly locate faults, demonstrating a high degree of intelligence.

[0024] This invention improves safety by employing non-contact ignition, thus eliminating the risk of backfire; and features an inherently safe design for the entire system. Attached Figure Description

[0025] Figure 1 This is a schematic diagram illustrating the composition and installation of a laser direct ignition device for an venting torch as described in this invention, along with the venting torch itself.

[0026] Among them, 1-Flame head, 2-Laser generator, 301-Transmission fiber optic cable, 302-Remote focusing head, 401-Purge unit, 401a-Automatic control valve A, 402-Circulating cooling unit, 402a-Automatic control valve B, 403-Fan, 501-Flame detection module, 502-Air venting detection module, 503-Laser energy detection module, 6-Intelligent control system, 7-Flame cylinder, 8-Flame support facilities, 9-Working power supply, 10-Air venting, 11-Vent pipeline. Detailed Implementation

[0027] 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.

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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 a part of the embodiments of the present invention, not all of them. 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. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention.

[0029] In the description of this invention, it should be understood that the orientation or positional relationship indicated by terms, etc., is based on the orientation or positional relationship shown in the drawings and is only for the convenience of describing this invention and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0030] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0031] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," "setting," "layout," and "fixing," etc., should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections. The specific means used are not limited to conventional mechanical connection methods such as screwing, interference fit, riveting, and threaded auxiliary connections. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0032] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0033] Example 1: A laser direct ignition device for flare torches addresses the problems of low ignition reliability, reliance on auxiliary fuel, and high maintenance costs in existing technologies. This invention directly generates a high-temperature plasma flame core in the flare gas flow using a high-energy pulsed laser, achieving reliable ignition of the main flare gas and completely eliminating the need for a pilot flame and its associated fuel supply system. Figure 1As shown, the system includes a laser generator 2, a beam transmission and focusing system, a lens protection and cooling system, a status monitoring unit, and an intelligent control system 6. The laser generator 2 is connected to the intelligent control system 6 via a cable. The beam transmission and focusing system is connected to the laser generator 2 and is used to apply the ignition laser generated by the laser generator 2 to the torch head 1 for laser ignition. The intelligent control system 6 is connected to the laser generator 2, the lens protection and cooling system, and the status monitoring unit. The beam transmission and focusing system and the lens protection and cooling system are connected, and the lens protection and cooling system is connected to the laser generator.

[0034] As a preferred design, the laser direct ignition device is used to ignite a venting torch, which is mainly composed of a torch head 1, a torch cylinder 7, a torch support facility 8, an air venting 10, and an air venting pipeline 11. It includes several major parts such as a laser generator 2, a beam transmission and focusing system, a lens protection and cooling system, a status monitoring unit, and an intelligent control system 6. Laser generator 2 serves as the core energy source. The ignition laser it generates is transmitted and focused through a beam transmission and focusing system, breaking down the air at the focal point to produce high-temperature, high-pressure plasma, which acts as the ignition nucleus for directly igniting the flare gas. Laser generator 2 is encapsulated in an all-weather protective cabinet and placed on the ground or in a safe area of ​​the flare platform. Laser generator 2 is connected to the intelligent control system 6 via a cable; it integrates a TEC semiconductor cooler and a laser diode driver power supply to ensure the stability of the output energy.

[0035] The beam transmission and focusing system is connected to the laser generator 2 and is used to focus the ignition laser generated by the laser generator 2 and break through the air at the focal point to generate a high-temperature and high-pressure plasma, which serves as the ignition nucleus for directly igniting the torch gas and acts on the torch head 1 to ignite the torch gas with laser.

[0036] The intelligent control system 6 is connected to the laser generator 2, the lens protection and cooling system and the status monitoring unit respectively. It is used to control the operation of the laser generator 2, control the working status of the lens protection and cooling system and control the status monitoring unit and receive the detection (monitoring) data obtained by it.

[0037] The beam transmission and focusing system is connected to the lens protection and cooling system. The lens protection and cooling system continuously supplies dry, clean air or nitrogen to the remote focusing head 302 in the beam transmission and focusing system through pipelines, so as to maintain a slight positive pressure inside the remote focusing head 302 and effectively prevent oil, moisture and dust from contaminating the optical lens. The lens protection and cooling system uses air cooling to force heat dissipation for the remote focusing head 302, which is under high load in the beam transmission and focusing system, to ensure that the equipment operates stably for a long time.

[0038] The lens protection and cooling system is connected to the laser generator 2. The lens protection and cooling system uses air cooling through pipes to force heat dissipation from the laser generator 2, ensuring that the equipment operates stably for a long time.

[0039] Example 2: This embodiment is a further optimization based on the above embodiments. The parts that are the same as those in the aforementioned technical solutions will not be repeated here. Figure 1 As shown, to further better realize the laser direct ignition device for venting torches described in this invention, the following configuration structure is specifically adopted: The beam transmission and focusing system includes a transmission fiber 301 and a remote focusing head 302. The remote focusing head 302 is located 2 to 5 meters below the torch head 1, and the axis of the light outlet of the remote focusing head 302 forms an angle of 30° to 60° with the direction of torch airflow. The remote focusing head 302 is connected to the laser generator 2 through the transmission fiber 301, and the lens protection and cooling system is connected to the remote focusing head 302.

[0040] As a preferred design, the beam transmission and focusing system includes a transmission fiber 301 and a remote focusing head 302. The remote focusing head 302 is connected to the laser generator 2 via the transmission fiber 301 laid along the torch support facility 8, transmitting laser energy from the generator to the vicinity of the torch head. The remote focusing head 302 is positioned 2-5 meters below and to the side of the torch head 1, with its output axis forming an angle of 30°-60° with the torch airflow direction. The remote focusing head 302 contains a collimating lens and a focusing lens group, which can precisely focus the laser beam onto the relatively low-velocity recirculation zone at the center of the torch head 1. This location is crucial, ensuring that the laser plasma ignition core has sufficient time to mix with the combustible gas and successfully ignite, preventing it from being instantly dispersed by the high-speed airflow.

[0041] The lens protection and cooling system is connected to the remote focusing head 302 via a stainless steel pipe, continuously supplying dry, clean air or nitrogen to the inside of the remote focusing head 302, maintaining a slight positive pressure inside the remote focusing head 302, and effectively preventing oil, moisture and dust from contaminating the optical lens.

[0042] Example 3: This embodiment is a further optimization based on any of the above embodiments. The parts that are the same as those in the foregoing technical solutions will not be repeated here. Figure 1 As shown, in order to better realize the laser direct ignition device for flare torches described in this invention, the following structure is specifically adopted: the transmission optical fiber 301 is an armored quartz optical fiber, which is a high temperature resistant, low loss quartz optical fiber, and has a metal armor protective layer.

[0043] Example 4: This embodiment is a further optimization based on any of the above embodiments. The parts that are the same as those in the foregoing technical solutions will not be repeated here. Figure 1 As shown, to further better realize the laser direct ignition device for venting torches described in this invention, the following structure is specifically adopted: the lens protection and cooling system is provided with a purge unit 401, a circulating cooling unit 402 and a fan 403. The purge unit 401 is connected to the remote focusing head 302 through a pipe. The circulating cooling unit 402 is connected to the laser generator 2 and the remote focusing head 302 through pipes respectively. The intelligent control system 6 controls the purge unit (self-controlled valve A401a) 401, the circulating cooling unit (self-controlled valve B402a) 402 and the fan 403. The fan 403 is connected to the purge unit 401 and the circulating cooling unit 402 respectively.

[0044] As a preferred design, the lens protection and cooling system mainly consists of a purge unit 401 with a self-regulating valve A401a and a circulating cooling unit 402 with a self-regulating valve B402a. The purge unit 401 is connected to the remote focusing head 302 through a stainless steel pipe. The purge unit 401 continuously supplies dry and clean air or nitrogen to the inside of the remote focusing head 302 through the stainless steel pipe, so that the inside of the remote focusing head 302 maintains a slight positive pressure, effectively preventing oil, moisture and dust from contaminating the optical lens.

[0045] The circulating cooling unit 402 is connected to the laser generator 2 and the remote focusing head 302 respectively through stainless steel pipes. It uses air cooling to force heat dissipation for the laser generator 2 and the high-load remote focusing head 302, ensuring stable operation of the equipment for a long time.

[0046] The blower 403 is connected to the purging unit 401 and the circulating cooling unit 402 respectively, and is used to provide the required air energy for the purging unit 401 and the circulating cooling unit 402. The air source for the purging unit 401 and the circulating cooling unit 402 is preferably nitrogen. If nitrogen is not available on site, a small high-pressure centrifugal blower (blower 403) can be used to provide air.

[0047] The intelligent control system 6 controls the self-control valve A401a of the purging unit 401, the self-control valve B402a of the circulating cooling unit 402, and the fan 403. The intelligent control system 6 issues open or close commands to control the opening and closing of the self-control valve A401a of the purging unit 401 and the self-control valve B402a of the circulating cooling unit 402, as well as the opening size of the valves. It also controls the opening and closing of the fan 403 and the magnitude of the airflow.

[0048] Example 5: This embodiment is a further optimization based on any of the above embodiments. The parts that are the same as those in the foregoing technical solutions will not be repeated here. Figure 1 As shown, to further better realize the laser direct ignition device for venting torches described in this invention, the following structure is specifically adopted: The status monitoring unit is equipped with a flame detection module 501, a venting air detection module 502, and a laser energy detection module 503. The flame detection module 501 is connected to the intelligent control system 6 via a control cable and is used to detect successful ignition and the torch combustion status. The venting air detection module 502 is installed on the venting pipeline 11 and is connected to the intelligent control system 6 via a control cable for detecting venting air emissions. The laser energy detection module 503 is built into the laser generator 2 and is connected to the intelligent control system 6 via a control cable for monitoring the energy and power of the output laser, providing data for the self-diagnosis of the intelligent control system 6.

[0049] As a preferred design, the status monitoring unit is equipped with three detection modules: a flame detection module 501, an air release detection module 502, and a laser energy detection module 503. The flame detection module 501 is connected to the intelligent control system 6 via a control cable and is used to detect successful ignition and the torch combustion status. The air release detection module 502 is installed on the venting pipeline 11 and is connected to the intelligent control system 6 via a control cable for detecting air release. The laser energy detection module 503 is built into the laser generator 2 and is connected to the intelligent control system 6 via a control cable for real-time monitoring of the energy and power of the output laser, providing data for the self-diagnosis of the intelligent control system 6.

[0050] Example 6: This embodiment is a further optimization based on any of the above embodiments. The parts that are the same as those in the foregoing technical solutions will not be repeated here. Figure 1 As shown, to further better realize the laser direct ignition device for venting torches described in this invention, the following configuration structure is specifically adopted: the flame detection module 501 adopts an ultraviolet flame detector or a sheathed thermocouple, and when an ultraviolet flame detector is used, it needs to be aligned with the laser focal point area; the venting detection module 502 adopts a flow switch, a pressure switch, a pressure transmitter, or an online chromatographic analyzer.

[0051] Example 7: This embodiment is a further optimization based on any of the above embodiments. The parts that are the same as those in the foregoing technical solutions will not be repeated here. Figure 1 As shown, to further better realize the laser direct ignition device for flare torches described in this invention, the following configuration structure is specifically adopted: the laser generator 2 is a pulsed Nd:YAG laser or a fiber laser, and the intelligent control system 6 is a PLC control system.

[0052] As the preferred design, laser generator 2, serving as the core energy source, employs a pulsed Nd:YAG laser or fiber laser with an output wavelength of 1064nm or 532nm (after frequency doubling). Key parameters are: single-pulse energy ≥ 500mJ, pulse width < 15ns, and peak power > 30MW. This high-energy, short-pulse, and high-peak-power characteristic is sufficient to break down the air at the focal point, generating a high-temperature, high-pressure plasma that serves as the ignition nucleus for directly igniting the flare gas. Laser generator 2 is encapsulated in an all-weather protective cabinet and placed on the ground or in a safe area of ​​the flare platform. Laser generator 2 is connected to the intelligent control system 6 via a cable.

[0053] The intelligent control system 6 adopts a PLC control system (a mature product familiar to technicians in existing industrial intelligent control systems; its structure, circuitry, and working principles will not be elaborated here). With a programmable logic controller (PLC) at its core, it receives ignition signals, air release signals, flame detector signals, and laser energy signals from the factory central control unit (host computer). Based on its built-in algorithms, the PLC outputs instructions to control the triggering of the laser generator 2, the start and stop of the purging unit 401, and the operation of the circulating cooling unit 402, and also possesses fault diagnosis and alarm functions.

[0054] Example 8: This embodiment is a further optimization based on any of the above embodiments. The parts that are the same as those in the foregoing technical solutions will not be repeated here. Figure 1 As shown, to further better realize the laser direct ignition device for flare torches described in this invention, the following configuration structure is specifically adopted: it also includes a working power supply 9 connected to the intelligent control system 6, for providing the required working voltage to the intelligent control system.

[0055] Example 9: A control method for a laser direct ignition device is disclosed, based on the aforementioned laser direct ignition device for flare torches, to address the problems of low ignition reliability, reliance on auxiliary fuel, and high maintenance costs in existing technologies. This invention directly generates a high-temperature plasma ignition core in the flare gas flow using a high-energy pulsed laser, achieving reliable ignition of the main flare gas and completely eliminating the need for a pilot flame and its associated fuel supply system. Figure 1 As shown, it includes the following steps: 1) System standby and self-test: After the laser direct ignition device is powered on, the intelligent control system 6 starts, the fan 403 starts working, the circulating cooling unit 402 starts working, and the purging unit 401 runs continuously for 10~30 seconds (preferably 10 seconds); the intelligent control system 6 performs a self-test and verifies the reading of the laser energy detection module 503; 2) Ignition trigger: The intelligent control system 6 receives the ignition trigger signal from the host computer or the venting detection module 502 installed on the inlet pipeline (venting pipeline 11) of the flare cylinder 7 in real time. When the value of the venting detection module 502 exceeds the preset safety threshold, it is determined that ignition is required and immediately proceeds to step 3). Ignition sequence: 3) Pre-purge and focus positioning: Increase the purge gas flow rate of the purge unit 401 (e.g., for 5-10 seconds, preferably 10 seconds) to ensure the cleaning of the focusing lens of the remote focusing head 302; at the same time, according to the preset torch gas parameter estimation model, the intelligent control system 6 can finely adjust the position of the laser focusing point (by controlling the adjustable focusing lens group in the remote focusing head 302 or selecting lenses with different focal lengths) so that the remote focusing head 302 is always in the optimal ignition area. 4) Laser Emission and Direct Ignition: The intelligent control system 6 sends a trigger command to the laser generator 2, which emits an ignition laser. This laser is transmitted via fiber optic cable 301 to the remote focusing head 302. The remote focusing head repeatedly punctures the air at a preset focal point, forming multiple stable plasma fire nuclei that directly ignite the flowing flare gas. In other words, the laser generator 2 emits a series of high-energy pulsed lasers at a specific frequency (e.g., 1-5 Hz). After transmission and focusing, the high-energy pulsed lasers repeatedly puncture the air at the preset focal point, forming multiple stable plasma fire nuclei that directly ignite the flowing flare gas. 5) Flame Confirmation: After the laser is emitted (e.g., within 3 to 5 seconds, preferably 5 seconds), the flame detection module 501 continuously monitors. If a stable flame signal is detected, the ignition is determined to be successful. The intelligent control system 6 controls the laser generator 2 to stop laser emission, stops the fan 403, and closes the self-control valve A401a of the purging unit 401 and the self-control valve B402a of the circulating cooling unit 402. The system then sends an ignition success signal to the host computer. 6) Retry and Alarm: If the flame detection module 501 fails to detect a flame within a preset time (e.g., 10-20 seconds, preferably 20 seconds), the ignition is deemed to have failed. The intelligent control system 6 can automatically start the retry program (up to 3 times). Before each retry, a post-purge time (5-10 seconds, preferably 5 seconds) is added. If multiple retry attempts fail, the laser emission is stopped. The installed audible and visual alarm can also be activated to trigger an alarm and generate a fault report (e.g., "insufficient laser energy", "lens contamination", "no gas").

[0056] Example 10: This embodiment is a further optimization based on any of the above embodiments. The parts that are the same as those in the foregoing technical solutions will not be repeated here. Figure 1As shown, to further improve the control method of the laser direct ignition device described in this invention, the following setting is specifically adopted: It also includes flameout protection: During torch combustion, if the flame detection module 501 detects flameout, the intelligent control system 6 immediately and unconditionally re-executes steps 4) to 6) until ignition is successful or laser emission stops, to ensure safety.

[0057] 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 are within the protection scope of the present invention.

Claims

1. A laser direct ignition device for an empty torch, characterized in that: The system includes a laser generator (2), a beam transmission and focusing system, a lens protection and cooling system, a status monitoring unit, and an intelligent control system (6). The laser generator (2) is connected to the intelligent control system (6) via a cable. The beam transmission and focusing system is connected to the laser generator (2) and is used to apply the ignition laser generated by the laser generator (2) to the torch head (1) for laser ignition. The intelligent control system (6) is connected to the laser generator (2), the lens protection and cooling system, and the status monitoring unit. The beam transmission and focusing system and the lens protection and cooling system are connected to each other. The lens protection and cooling system is connected to the laser generator (2).

2. The laser direct ignition device for an empty torch according to claim 1, characterized in that: The beam transmission and focusing system includes a transmission fiber (301) and a remote focusing head (302). The remote focusing head (302) is located 2 to 5 meters below the torch head (1), and the axis of the light outlet of the remote focusing head (302) forms an angle of 30° to 60° with the direction of torch airflow. The remote focusing head (302) is connected to the laser generator (2) through the transmission fiber (301), and the lens protection and cooling system is connected to the remote focusing head (302).

3. A laser direct ignition device for an empty torch according to claim 2, characterized in that: The transmission optical fiber (301) is an armored quartz optical fiber.

4. A laser direct ignition device for an exhaust torch according to claim 2 or 3, characterized in that: The lens protection and cooling system is equipped with a purge unit (401), a circulating cooling unit (402), and a fan (403). The purge unit (401) is connected to the remote focusing head (302) through a pipe. The circulating cooling unit (402) is connected to the laser generator (2) and the remote focusing head (302) through pipes respectively. The intelligent control system (6) controls the purge unit (401), the circulating cooling unit (402), and the fan (403). The fan (403) is connected to the purge unit (401) and the circulating cooling unit (402) respectively.

5. A laser direct ignition device for an exhaust torch according to claim 1, 2, or 3, characterized in that: The status monitoring unit is equipped with a flame detection module (501), an air release detection module (502), and a laser energy detection module (503). The flame detection module (501) is connected to the intelligent control system (6) via a control cable. The air release detection module (502) is installed on the venting pipeline (11) and is connected to the intelligent control system (6) via a control cable. The laser energy detection module (503) is built into the laser generator (2) and is connected to the intelligent control system (6) via a control cable.

6. A laser direct ignition device for an exhaust torch according to claim 5, characterized in that: The flame detection module (501) uses an ultraviolet flame detector or a sheathed thermocouple, and the air release detection module (502) uses a flow switch, a pressure switch, a pressure transmitter, or an online chromatograph.

7. A laser direct ignition device for an exhaust torch according to claim 1, 2, 3, or 6, characterized in that: The laser generator (2) is a pulsed Nd:YAG laser or a fiber laser, and the intelligent control system (6) is a PLC control system.

8. A laser direct ignition device for an exhaust torch according to claim 1, 2, 3, or 6, characterized in that: It also includes a power supply (9) connected to the intelligent control system (6).

9. A control method for a laser direct ignition device, characterized in that: Based on the laser direct ignition device for an empty torch as described in any one of claims 1 to 8, the method includes the following steps: 1) After the laser direct ignition device is powered on, the intelligent control system (6) starts, the fan (403) starts working, the circulating cooling unit (402) starts working, and the purging unit (401) continues to run; the intelligent control system (6) performs self-test and verifies the reading of the laser energy detection module (503); 2) The intelligent control system (6) receives the ignition trigger signal from the host computer or the air release detection module (502) in real time. When the value of the air release detection module (502) exceeds the preset safety threshold, it determines that ignition is required and immediately proceeds to step 3). 3) Increase the purge gas flow rate of the purge unit (401) to ensure the remote focusing head (302) is clean; at the same time, according to the preset torch gas parameter estimation model, the intelligent control system (6) fine-tunes the position of the laser focusing point so that the remote focusing head (302) is always in the optimal ignition area. 4) The intelligent control system (6) sends a trigger command to the laser generator (2), the laser generator emits an ignition laser, and transmits it to the remote focusing head (302) through the transmission fiber (301). The remote focusing head (302) repeatedly breaks through the air at the preset focal point to form multiple stable plasma fire nuclei, which directly ignite the flowing torch gas. 5) The flame detection module (501) continuously monitors after the laser is emitted. If a stable flame signal is detected, the ignition is determined to be successful. The intelligent control system (6) controls the laser generator (2) to stop the laser emission, and stops the fan (403) and shuts down the purging unit (401) and the circulating cooling unit (402), and sends an ignition success signal to the host computer. 6) If the flame detection module (501) does not detect a flame within the preset time, the ignition is determined to have failed. The intelligent control system (6) automatically starts the retry program. Before the retry, a post-purge time is added. If the retry fails multiple times, the laser emission is stopped and a fault report is generated.

10. The control method for a laser direct ignition device according to claim 9, characterized in that: During torch combustion, if the flame detection module (501) detects flameout, the intelligent control system (6) immediately re-executes steps 4)-6) until ignition is successful or laser emission stops.

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