Intelligent Control System and Method for Spectral Feedback Plasma Free Radical Ammonia-Coal Co-firing

Abstract

This invention relates to the field of clean combustion technology, and particularly to a spectral feedback plasma radical ammonia-coal co-firing intelligent control system and method. It primarily addresses the shortcomings of existing ammonia-coal co-firing technologies, such as passive control methods and the inability to precisely intervene in chemical reaction pathways, and proposes the following technical solution: The intelligent control system is integrated into the ammonia-coal co-firing burner and boiler, including a plasma radical generator module, a multi-parameter laser spectral sensing module, and an intelligent control module; the plasma radical generator module includes at least one plasma discharge unit integrated within the burner housing, with the active component injection port of the plasma discharge unit pointing towards a specific reaction region inside the burner. This invention overcomes the bottleneck of stable combustion in ammonia-coal co-firing through precise plasma radical injection and spectral feedback closed-loop control, reducing NO₂ levels. X Emissions and energy consumption can be adaptively controlled under operating conditions, which has environmental, economic and engineering promotion value.

Description

Technical Field

[0001] This invention relates to the field of clean combustion technology, and in particular to a smart control system and method for spectral feedback plasma free radical ammonia-coal co-firing. Background Technology

[0002] As a core pillar of energy supply, carbon emission control is a crucial link in achieving the "dual carbon" goal for coal-fired power plants. Ammonia, as a zero-carbon fuel, has advantages such as high energy density and clean combustion products. Blending ammonia with coal has become an important technical approach for reducing carbon emissions in coal-fired power plants, and it is expected to significantly reduce carbon intensity while ensuring the stability of energy supply.

[0003] However, ammonia-coal co-firing technology faces two major challenges: first, ammonia is difficult to ignite and has a slow flame propagation speed, which can easily lead to unstable combustion or even flameout, especially at low loads or high ammonia blending ratios; second, ammonia itself contains nitrogen, which can easily generate a large amount of nitrogen oxides during high-temperature combustion, resulting in excessive NOx emissions.

[0004] Existing low-NOx combustion technologies mainly rely on physical-level regulation, such as the technologies disclosed in patents CN114484438B and CN118346994A, which suppress NOx formation through methods such as fuel staging, air staging, and creating rich-lean deviations. These methods are essentially passive, that is, creating an environment that suppresses NOx formation by optimizing the flow field and mixing process, but their effectiveness is difficult to maintain optimally when boiler load, coal type, and ammonia blending ratio change significantly.

[0005] On the other hand, plasma technology has been attempted for use in the field of combustion. Existing related technologies mostly focus on utilizing the thermal effect of plasma. For example, patent CN119468215B discloses "A plasma-assisted ammonia-coal co-firing ignition and stabilization system and method" and patent CN118687148A discloses "A plasma-assisted ammonia-coal co-firing device". Both of these technologies directly ignite the fuel or increase the local combustion temperature by generating a high-temperature plasma torch to achieve stable combustion. However, these technologies mainly utilize the thermal effect of plasma, that is, directly ignite the fuel by generating a high-temperature plasma torch. This results in high power consumption, short electrode life, and does not delve into the level of precise intervention in the combustion chemical reaction path.

[0006] The introduction of ammonia fuel brings both new opportunities and challenges: amino radicals in its decomposition products are known to be highly efficient NOx reducing agents. However, existing technologies have not yet overcome the core technical bottleneck of "actively controlling the combustion chemical reaction pathway": they cannot achieve the directional generation and precise injection of specific active radicals, nor do they possess a real-time feedback control mechanism that dynamically matches combustion conditions. This results in an inability to adaptively adjust the control strategy based on dynamic changes such as NH3 escape and NOx generation during ammonia-coal co-firing. Therefore, this invention proposes a spectral feedback plasma radical ammonia-coal co-firing intelligent control system and method. Summary of the Invention

[0007] This invention addresses the shortcomings of existing ammonia-coal co-firing technologies, such as passive control methods, poor adaptability to operating conditions, and inability to precisely intervene in chemical reaction pathways, which make it difficult to simultaneously solve the two core problems of stable combustion and low NOx emissions. It proposes a spectral feedback plasma free radical ammonia-coal co-firing intelligent control system and method.

[0008] The technical solution of the present invention: a spectral feedback plasma free radical ammonia-coal co-firing intelligent control system, wherein the intelligent control system is integrated into the ammonia-coal co-firing burner and the boiler, and includes a plasma free radical generator module, a multi-parameter laser spectral sensing module and an intelligent control module;

[0009] The plasma radical generator module includes at least one plasma discharge unit integrated in the burner housing. The active component injection port of the plasma discharge unit is directed to a specific reaction region inside the burner, and the plasma discharge unit is connected to the carrier gas supply system.

[0010] The multi-parameter laser spectral sensing module includes at least one set of tunable semiconductor laser absorption spectral sensors. The laser emitter and receiver of the sensors are installed at the burner outlet for real-time online measurement of NH3 concentration and NO concentration at the burner outlet and inside the furnace. X concentration;

[0011] The intelligent control module includes a central controller, a boiler main control system, a plasma radical generator control module, a carrier gas control module, and a multi-parameter laser spectral sensing control module. The central controller is connected to the plasma radical generator control module, the carrier gas control module, the multi-parameter laser spectral sensing control module, and the boiler main control system via a communication protocol. The plasma radical generator control module, the carrier gas control module, and the multi-parameter laser spectral sensing control module are respectively connected to the plasma radical generator module, the carrier gas supply system, and the multi-parameter laser spectral sensing module via electrical wires.

[0012] The ammonia-coal co-firing burner includes a burner shell and a central primary air duct, an annular ammonia gas channel, and a secondary air channel arranged concentrically from the inside to the outside. Both the annular ammonia gas channel and the secondary air channel are equipped with steplessly adjustable swirl blades. An inverted conical blunt body is provided between the central primary air duct and the secondary air channel. The small end of the blunt body is fixedly connected to the upstream of the burner shell, and the large end points towards the furnace, which is used to form a stable flue gas recirculation zone downstream of it.

[0013] Optionally, the plasma discharge unit is installed at the outlet of the annular ammonia channel of the burner, and a plasma free radical generator is installed at the first position, with its injection direction pointing towards the ammonia jet to inject plasma free radicals into the ammonia jet region.

[0014] Optionally, the plasma discharge unit is also installed inside the inverted conical blunt body between the primary air duct and the secondary air duct of the burner, and a second plasma free radical generator is installed accordingly. Its injection direction is reversed or obliquely directed towards the flue gas recirculation zone formed behind the large end of the blunt body, so as to inject plasma free radicals into the recirculation zone.

[0015] Optionally, the plasma discharge unit has an angle of 30° or 60° between its nozzle axis and the burner axis.

[0016] Optionally, the first-position plasma radical generator and the second-position plasma radical generator are modular structures and employ sliding arc discharge; the first-position plasma radical generator and the second-position plasma radical generator are detachably mounted on the burner housing and the inverted conical blunt body respectively through a mechanical interface sleeve;

[0017] The plasma radical generator at the first position has the same structure as the plasma radical generator at the second position.

[0018] Optionally, the power of the first and second position plasma radical generators is adjustable, with a power consumption of 80-800W.

[0019] Optionally, the carrier gas supply system is further provided with multiple sets of connecting pipelines, which are connected to a carrier gas supply and switching system. The carrier gas supply and switching system includes pipelines that supply air and ammonia to the first position plasma radical generator and the second position plasma radical generator respectively, and a flow controller, for realizing independent switching of the carrier gas path and precise flow control.

[0020] Optionally, the operating condition adaptive optimization control strategy built into the central controller includes the following control strategies:

[0021] When the NH3 concentration is detected to be higher than the first set threshold, it is determined that there is ammonia escape or incomplete decomposition. Then, the power of the plasma free radical generator located at the first position is increased, and air is introduced as a carrier gas to generate H, O, OH free radicals to promote the decomposition and combustion of ammonia.

[0022] When NO is detected X If the concentration exceeds the second preset threshold, it is determined that the NOx generation is too high. The power of the plasma radical generator located at the second position is activated or increased, and ammonia gas is switched to be introduced as the carrier gas to generate NH2-rich radicals to reduce NO. X .

[0023] The adaptive optimization control strategy for operating conditions also includes the following control strategies:

[0024] Based on the boiler load signal and the ammonia-to-coal ratio signal, a collaborative decision is made regarding the start-up and shutdown, power allocation, and carrier gas selection strategies for the first and second position plasma radical generators. Specifically, this includes the following processing methods:

[0025] When the boiler is under low load, the first position plasma free radical generator is activated first to inject H, O, and OH free radicals to enhance stable combustion.

[0026] When the boiler is operating at a high ammonia ratio, both the first-position plasma radical generator and the second-position plasma radical generator are activated simultaneously. The first-position plasma radical generator introduces air to generate free radicals, ensuring the complete decomposition of ammonia. The second-position plasma radical generator introduces ammonia gas to generate NH2-rich free radicals to reduce NO. X .

[0027] This invention also proposes a spectral feedback plasma free radical ammonia-coal co-combustion intelligent control method. Using the aforementioned control system, closed-loop precise control of the combustion process is achieved through active intervention in the ammonia-nitrogen conversion pathway, comprising the following steps:

[0028] Step 1: System startup and initialization, the central controller loads the adaptive optimization control strategy model under the operating conditions;

[0029] Step 2: Monitor the NH3 concentration and NO concentration at the burner outlet or inside the furnace in real time using a multi-parameter laser spectral sensing module. X The concentration is simultaneously monitored by the boiler's main control system, which collects real-time boiler load signals and ammonia-to-coal ratio signals.

[0030] Step 3: Combine the NH3 and NO X Concentration signal, boiler load signal and ammonia-coal ratio signal are input to the central controller. The central controller determines the type of free radical required, the optimal injection location and injection energy under the current operating conditions according to the preset strategy.

[0031] Step 4: The central controller generates control commands, which act on the carrier gas control module and the plasma free radical generator control module, thereby driving the carrier gas supply and switching system and the designated plasma discharge unit to adjust the carrier gas conditions and discharge power, accurately inject the target plasma free radicals into the burner, and actively intervene in the combustion chemical reaction path.

[0032] Step 5: Continuously monitor NH3 and NO X Concentration changes enable closed-loop active control of the combustion process until the parameters stabilize within the target range.

[0033] In summary, this application includes at least one of the following beneficial technical effects:

[0034] This invention enhances the reactivity of ammonia from the fundamental level of chemical reaction by directionally injecting oxidizing free radicals such as H, O, and OH. It effectively solves the problems of difficult ammonia ignition, slow flame propagation, and easy extinguishing under low load and high ammonia blending conditions. It enables boilers to operate stably under low load and ammonia blending ratios as high as 50%, significantly expanding the safe operating range of ammonia-coal co-firing boilers and providing core guarantees for the large-scale co-firing of ammonia fuel.

[0035] Furthermore, the multi-parameter laser spectral sensing module is used to detect NH3 and NO. X Real-time online monitoring of concentration, combined with operating parameters such as boiler load and ammonia blending ratio, constructs a fully closed-loop intelligent control system consisting of sensing, decision-making, execution, and feedback. The central controller, through its built-in adaptive operating condition strategy, can automatically determine the combustion state and accurately match the plasma free radical type, injection location, and energy parameters. It can adaptively cope with complex operating conditions such as load fluctuations, coal type changes, and ammonia blending ratio adjustments without manual intervention, completely solving the defects of existing technologies that rely on fixed operating conditions and have poor adaptability, and ensuring that the combustion system is always in the optimal operating state.

[0036] Furthermore, this invention innovatively utilizes the highly efficient reduction properties of NH2 amino radicals, a product of ammonia decomposition, to precisely inject NH2-rich active gas clusters into the flue gas recirculation zone through a plasma discharge unit. This allows for in-situ reduction of NOx in its early stages, fundamentally solving the NOx emission problem. Compared to existing passive flow field optimization technologies, this invention improves NOx removal efficiency. Simultaneously, by injecting free radicals at the first position, it promotes the full decomposition of ammonia, controlling the ammonia escape concentration below 50 ppm. This achieves synergistic optimization of stable combustion and nitrogen control, easily meeting stringent environmental emission standards.

[0037] Furthermore, this invention employs a modular sliding arc discharge plasma generator, which consumes far less power than existing plasma ignition / combustion technologies, significantly reducing operating energy consumption. At the same time, by avoiding ammonia escape, improving combustion efficiency, and reducing NOx treatment costs, its overall economic benefits are significantly enhanced. The plasma free radical generator of this invention adopts a modular and detachable structure, which can be quickly installed on the shell of an existing ammonia-coal co-firing burner or an inverted conical blunt body through a mechanical interface sleeve, without the need for large-scale modification of the main structure of the burner, making it highly adaptable.

[0038] In summary, this invention overcomes the bottleneck of stable combustion in ammonia-coal co-firing by precise plasma radical injection and spectral feedback closed-loop control, significantly reducing NOx emissions and energy consumption, achieving adaptive control under operating conditions, and possessing environmental, economic, and engineering promotion value. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the control system structure principle proposed in this invention and its integration on the burner;

[0040] Figure 2 This is a flowchart of the control method proposed in this invention;

[0041] Figure label:

[0042] 1. Burner housing; 2. Central primary air duct; 3. Annular ammonia gas passage; 4. Secondary air passage; 5. First-position plasma radical generator; 6. Second-position plasma radical generator; 7. Carrier gas supply and switching system; 8. Laser emitter; 9. Laser receiver; 10. Central controller; 11. Boiler main control system; 12. Flue gas recirculation zone; 51. Plasma radical generator control module; 52. Carrier gas control module; 53. Multi-parameter laser spectral sensing control module; Detailed Implementation

[0043] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0044] The components of the embodiments of the invention described and shown in the accompanying drawings can typically be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of the invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention.

[0045] Example: Figures 1 to 2As shown, the spectral feedback plasma free radical ammonia-coal co-firing intelligent control system proposed in this invention is integrated into the ammonia-coal co-firing burner and boiler, and includes a plasma free radical generator module, a multi-parameter laser spectral sensing module and an intelligent control module. The plasma radical generator module includes at least one plasma discharge unit integrated within the burner housing 1. The active component injection port of the plasma discharge unit is directed towards a specific reaction region inside the burner, and the plasma discharge unit is connected to the carrier gas supply system. The carrier gas supply system is connected to a carrier gas supply and switching system 7. The carrier gas supply and switching system 7 includes pipelines and flow controllers that supply air and ammonia to the first position plasma radical generator 5 and the second position plasma radical generator 6, respectively, for realizing independent switching of the carrier gas path and precise flow control.

[0047] The multi-parameter laser spectral sensing module includes at least one set of tunable semiconductor laser absorption spectral sensors. The laser emitter 8 and laser receiver 9 of the sensors are installed at the burner outlet for real-time online measurement of NH3 concentration and NO concentration at the burner outlet and inside the furnace. X Concentration; The multi-parameter laser spectral sensing module adopts TDLAS technology. The laser emitter 8 and laser receiver 9 are installed facing each other on the furnace wall near the burner outlet. The measurement optical path passes through the entire flame area, enabling simultaneous real-time online measurement of NH3 and NO concentrations at the path integral level. X concentration.

[0048] The intelligent control module includes a central controller 10, which is connected to the plasma radical generator control module 51, the multi-parameter laser spectral sensing control module 53, the carrier gas control module 52, and the boiler main control system 11 via a communication protocol. The plasma radical generator control module 51, the multi-parameter laser spectral sensing control module 53, and the carrier gas control module 52 are respectively connected to the plasma radical generator module, the multi-parameter laser spectral sensing module, and the flow controller of the carrier gas supply system via wires. The central controller 10 of the intelligent control module adopts an industrial-grade PLC or an embedded industrial computer, which synchronously receives laser sensing signals and operating data from the boiler main control system 11 via data lines to build a complete data foundation for judging the operating conditions.

[0049] The central controller 10 compares the collected real-time data with built-in thresholds and control models to determine the current combustion state and output targeted control commands. The central controller 10's built-in adaptive optimization control strategy includes the following control methods:

[0050] When the NH3 concentration is detected to be higher than the first set threshold, it is determined that there is ammonia escape or incomplete decomposition. Then the power of the plasma free radical generator 5 located in the first position is increased, and air is introduced as a carrier gas to generate H, O, OH free radicals to promote the decomposition and combustion of ammonia.

[0051] When NO is detected X If the concentration exceeds the second preset threshold, it is determined that the NOx generation is too high. The power of the plasma radical generator 6 located at the second position is activated or increased, and ammonia gas is switched to be introduced as the carrier gas to generate NH2-rich radicals to reduce NO. X ;

[0052] The adaptive optimization control strategy also includes the following control methods:

[0053] Based on the boiler load signal and the ammonia-to-coal ratio signal, the system collaboratively decides on the start-up, shutdown, power allocation, and carrier gas selection strategies for the first-position plasma radical generator 5 and the second-position plasma radical generator 6, specifically including the following processing methods:

[0054] When the boiler is under low load, the first position plasma free radical generator 5 is activated first to inject H, O, OH free radicals to enhance stable combustion.

[0055] When the boiler is operating at a high ammonia ratio, the first-position plasma radical generator 5 and the second-position plasma radical generator 6 are activated simultaneously. The first-position plasma radical generator 5 introduces air to generate free radicals, ensuring the complete decomposition of ammonia. The second-position plasma radical generator 6 introduces ammonia gas to generate NH2-rich free radicals to reduce NO. X .

[0056] The core decision-making logic, combined with practical examples, is as follows:

[0057] Case 1 illustrates a low-load stable combustion condition: If the boiler load is monitored to be <50% and the NH3 reading is >50ppm, it is determined to be low-load ammonia decomposition or insufficient combustion. Controller decision: Start the first position plasma free radical generator 5, set the power to 500W, and instruct the carrier gas supply and switching system 7 to introduce air. By adjusting the generator power and carrier air flow rate, ammonia decomposition is strongly promoted to enhance stable combustion.

[0058] Case 2 is a high ammonia ratio nitrogen control condition: if the ammonia ratio is monitored to be >30% and NO... XA reading >200 mg / m³ indicates that the high ammonia doping ratio is causing the NOx increase. The controller decides to simultaneously activate the first-position plasma radical generator 5 and the second-position plasma radical generator 6. The first-position plasma radical generator 5 operates at 300 W with air as the carrier gas to ensure complete ammonia decomposition; the second-position generator 6 operates at 600 W with ammonia as the carrier gas to generate a large number of NH2 radicals.

[0059] Case 3 is a steady-state condition: if all parameters are: NH3, NO X The concentration, boiler load, and ammonia blending ratio are all within excellent ranges. The controller decides to either maintain the current system operation or enter a low-power monitoring mode to reduce energy consumption.

[0060] The ammonia-coal co-firing burner includes a burner shell 1, and a central primary air duct 2, an annular ammonia gas passage 3, and a secondary air passage 4 arranged concentrically from the inside to the outside.

[0061] The plasma discharge unit is installed at the outlet of the annular ammonia channel 3 of the burner, and the plasma free radical generator 5 is installed at the first position. Its jetting direction is directed towards the ammonia jet, and it is used to inject plasma free radicals into the ammonia jet region.

[0062] The plasma discharge unit is also installed inside the inverted conical blunt body between the central primary air duct 2 and the secondary air channel 4, and a second-position plasma free radical generator 6 is installed accordingly. Its injection direction is reversed or obliquely directed towards the flue gas recirculation zone 12 formed behind the large end of the blunt body, which is used to inject plasma free radicals into the recirculation zone. The angle between the axis of the plasma discharge unit's injection port and the axis of the burner is 30° or 60°.

[0063] The first-position plasma radical generator 5 and the second-position plasma radical generator 6 are modular structures. The first-position plasma radical generator 5 and the second-position plasma radical generator 6 can be detachably installed on the burner housing 1 and the inverted conical blunt body through a mechanical interface sleeve.

[0064] The first-position plasma radical generator 5 and the second-position plasma radical generator 6 have the same structure.

[0065] In this embodiment, the first-position plasma radical generator 5 is installed on the outlet wall of the annular ammonia channel 3, with its nozzle radially pointing towards the ammonia jet; the second-position plasma radical generator 6 is installed on an inverted conical blunt flame stabilizer, with its nozzle pointing in the opposite direction towards the flue gas recirculation zone 12 at the center of the burner, ensuring precise injection of radicals into the key reaction area. Simultaneously, the two generators are connected to a carrier gas supply and switching system 7 via pipelines. This system includes independent air and ammonia supply pipelines and flow controllers, allowing for individual switching of gas paths and flow rate adjustment according to instructions, achieving precise preparation of radical jets with different components.

[0066] The power of the first position plasma radical generator 5 and the second position plasma radical generator 6 is adjustable, and the power consumption of the discharge unit is 80-800W.

[0067] Both the annular ammonia channel 3 and the secondary air channel 4 are equipped with steplessly adjustable swirl blades, which can flexibly control the intensity of fluid swirl. An inverted conical blunt body is installed between the central primary air duct 2 and the secondary air channel 4. The small end of the blunt body is fixedly connected to the upstream of the burner shell 1, and the large end points towards the furnace. It is used to form a stable flue gas recirculation zone 12 downstream. The flue gas recirculation zone 12 provides a basic flow field environment for the fuel to be fully mixed, for stable ignition, and for the efficient reaction of free radicals with reactants.

[0068] This embodiment also proposes a plasma radical ammonia-coal co-combustion intelligent control method based on spectral feedback. Using the aforementioned control system, closed-loop precise control of the combustion process is achieved through active intervention in the ammonia-nitrogen conversion pathway, including the following steps:

[0069] Step 1: System startup and initialization, the central controller 10 loads the adaptive optimization control strategy model under the operating conditions;

[0070] Step 2: Monitor the NH3 concentration and NO concentration at the burner outlet or inside the furnace in real time using a multi-parameter laser spectral sensing module. X Concentration, while simultaneously collecting real-time boiler load signals and ammonia-to-coal ratio signals;

[0071] Step 3: Combine NH3 concentration and NO X Concentration signal, boiler load signal and ammonia-coal ratio signal are input to central controller 10. Central controller 10 determines the type of free radical required under the current working condition, the optimal injection location and injection energy according to preset strategy.

[0072] Step 4: The central controller 10 generates control commands, which act on the carrier gas control module 52 and the plasma free radical generator control module 51, thereby driving the carrier gas supply and switching system 7 and the designated plasma discharge unit to adjust the carrier gas conditions and discharge power, accurately inject the target plasma free radicals into the burner, and actively intervene in the combustion chemical reaction path.

[0073] Step 5: Continuously monitor NH3 and NO X Concentration changes enable closed-loop active control of the combustion process until the parameters stabilize within the target range.

[0074] The working process of this control method embodiment is as follows: Startup and initialization: After the system starts up, the central controller 10 loads the optimized control strategy model.

[0076] Data Acquisition: Real-time acquisition of laser spectral data, including NH3 and NO at the burner outlet or fixed location in the furnace. X Concentration, and boiler operating data, including boiler load and ammonia blending ratio.

[0077] Status judgment and decision-making: The central controller 10 compares real-time data with built-in thresholds and models, calculates and outputs control commands;

[0078] Action execution: According to the control command, adjust the discharge power and carrier gas conditions of the designated plasma discharge unit, and accurately inject the target plasma free radicals into the burner to achieve closed-loop active control of the combustion process.

[0079] The above specific embodiments are merely optional embodiments of the present invention. Based on the technical solutions of the present invention and the relevant teachings of the above embodiments, those skilled in the art can make various alternative improvements and combinations to the above specific embodiments.

Claims

1. A spectral feedback plasma free radical ammonia-coal co-firing intelligent control system, characterized in that, The intelligent control system is integrated into the ammonia-coal co-firing burner and boiler, and includes a plasma free radical generator module, a multi-parameter laser spectral sensing module and an intelligent control module. The plasma radical generator module includes at least one plasma discharge unit integrated in the burner housing (1), the active component injection port of the plasma discharge unit is directed to a specific reaction area inside the burner, and the plasma discharge unit is connected to the carrier gas supply system. The multi-parameter laser spectral sensing module includes at least one set of tunable semiconductor laser absorption spectral sensors. The laser emitting end (8) and laser receiving end (9) of the sensors are installed at the burner outlet for real-time online measurement of NH3 concentration and NO concentration at the burner outlet and in the furnace. X concentration; The intelligent control module includes a central controller (10), a boiler main control system (11), a plasma free radical generator control module (51), a carrier gas control module (52), and a multi-parameter laser spectrum sensing control module (53). The central controller (10) is connected to the plasma free radical generator control module (51), the carrier gas control module (52), the multi-parameter laser spectrum sensing control module (53), and the boiler main control system (11) via a communication protocol. The plasma free radical generator control module (51), the carrier gas control module (52), and the multi-parameter laser spectrum sensing control module (53) are respectively connected to the plasma free radical generator module, the carrier gas supply system, and the multi-parameter laser spectrum sensing module via wires. The ammonia-coal co-firing burner includes a burner shell (1) and a central primary air duct (2), an annular ammonia gas channel (3) and a secondary air channel (4) arranged concentrically from the inside to the outside. The annular ammonia gas channel (3) and the secondary air channel (4) are both equipped with steplessly adjustable swirl blades. An inverted conical blunt body is provided between the central primary air duct (2) and the secondary air channel (4). The small end of the blunt body is fixedly connected to the upstream of the burner shell (1), and the large end points towards the furnace, which is used to form a stable flue gas recirculation zone (12) downstream of it.

2. The intelligent control system for spectral feedback plasma free radical ammonia-coal co-firing according to claim 1, characterized in that, The plasma discharge unit is installed at the outlet of the annular ammonia gas channel (3) of the burner, and a plasma free radical generator (5) is installed at the first position. Its spray direction is directed towards the ammonia gas jet, and it is used to inject plasma free radicals into the ammonia gas jet region.

3. The intelligent control system for spectral feedback plasma free radical ammonia-coal co-firing according to claim 2, characterized in that, The plasma discharge unit is also installed inside the inverted conical blunt body between the primary air duct (2) and the secondary air duct (4) of the burner, and a second position plasma free radical generator (6) is installed accordingly. Its spray direction is reversed or obliquely directed towards the flue gas recirculation zone (12) formed behind the large end of the blunt body, and is used to inject plasma free radicals into the recirculation zone.

4. The intelligent control system for spectral feedback plasma free radical ammonia-coal co-firing according to claim 3, characterized in that, The plasma discharge unit has an angle of 30° or 60° between its nozzle axis and the burner axis.

5. The intelligent control system for spectral feedback plasma free radical ammonia-coal co-firing according to claim 4, characterized in that, The first position plasma radical generator (5) and the second position plasma radical generator (6) are modular structures and adopt sliding arc discharge. The first position plasma radical generator (5) and the second position plasma radical generator (6) are detachably installed on the burner housing (1) and the inverted conical blunt body respectively through a mechanical interface sleeve. The first position plasma radical generator (5) and the second position plasma radical generator (6) have the same structure.

6. The intelligent control system for spectral feedback plasma free radical ammonia-coal co-firing according to claim 5, characterized in that, The power of the first position plasma radical generator (5) and the second position plasma radical generator (6) is adjustable, with a power consumption of 80-800W.

7. The intelligent control system for spectral feedback plasma free radical ammonia-coal co-firing according to claim 6, characterized in that, The carrier gas supply system is also provided with multiple sets of connecting pipelines, which are connected to a carrier gas supply and switching system (7). The carrier gas supply and switching system (7) includes pipelines and flow controllers that supply air and ammonia to the first position plasma radical generator (5) and the second position plasma radical generator (6) respectively, for realizing independent switching of ammonia and air in the carrier gas path and precise flow control.

8. The intelligent control system for spectral feedback plasma free radical ammonia-coal co-firing according to claim 1, characterized in that, The operating condition adaptive optimization control strategy built into the central controller (10) includes the following control methods: When the NH3 concentration is detected to be higher than the first set threshold, it is determined that there is ammonia escape or incomplete decomposition. Then the power of the plasma free radical generator (5) located at the first position is increased, and air is introduced as a carrier gas to generate H, O, OH free radicals to promote the decomposition and combustion of ammonia. When NO is detected X If the concentration exceeds the second set threshold, it is determined that the NOx generation is too high. The power of the plasma free radical generator (6) located at the second position is activated or increased, and ammonia gas is switched to be introduced as the carrier gas to generate NH2-rich free radicals to reduce NO. X ; The adaptive optimization control strategy for operating conditions also includes the following control methods: Based on the boiler load signal and the ammonia-coal ratio signal, the start-up, shutdown, power distribution, and carrier gas selection strategies of the first-position plasma radical generator (5) and the second-position plasma radical generator (6) are collaboratively decided, specifically including the following processing methods: When the boiler is under low load, the first position plasma free radical generator (5) is activated first to inject H, O, OH free radicals to enhance stable combustion. When the boiler is in a high ammonia ratio operating condition, the first position plasma radical generator (5) and the second position plasma radical generator (6) are activated simultaneously. The first position plasma radical generator (5) introduces air to generate free radicals to ensure the full decomposition of ammonia, and the second position plasma radical generator (6) introduces ammonia gas to generate NH2-rich free radicals to reduce NOx.

9. A method for intelligent control of spectral feedback plasma free radical ammonia-coal co-firing, characterized in that, The control system described in any one of claims 1-8 achieves closed-loop precise control of the combustion process by actively intervening in the ammonia-nitrogen conversion pathway, comprising the following steps: Step 1: System startup and initialization, the central controller (10) loads the adaptive optimization control strategy model for the operating conditions; Step 2: Monitor the NH3 concentration and NO concentration at the burner outlet or inside the furnace in real time using the multi-parameter laser spectral sensing control module (53). X Concentration, and at the same time, the boiler real-time load signal and ammonia-coal ratio signal are collected through the boiler main control system (11); Step 3: Combine the NH3 and NO X Concentration signal, boiler load signal and ammonia-coal ratio signal are input to central controller (10). Central controller (10) determines the type of free radical required under the current working condition, the optimal injection location and the injection energy according to the preset strategy. Step 4: The central controller (10) generates control commands, which are applied to the carrier gas control module (52) and the plasma free radical generator control module (51) to drive the carrier gas supply and switching system (7) and the designated plasma discharge unit to adjust the carrier gas conditions and discharge power, accurately inject the target plasma free radicals into the burner, and actively intervene in the combustion chemical reaction path. Step 5: Continuously monitor NH3 and NO X Concentration changes enable closed-loop active control of the combustion process until the parameters stabilize within the target range.

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