Flue gas denitrification reducing agent precise injection control system based on flow feedback

Abstract

The present invention discloses a precise injection control system for flue gas denitrification reducing agents based on flow feedback, which relates to the technical field of flue gas denitrification. The system comprises: a flue gas pipeline staging module that divides the denitrification cycle into sections and deploys multi-point injection based on NOx concentration, constructs a cascade denitrification structure, and limits the NOx concentration decrease in sections. A control establishment module mathematically reconstructs the cascade denitrification structure, constructs a denitrification controller, combines multivariable decoupling decision-making with tracer simulation, and connects the front-end device through a network protocol. The injection decision module triggers the denitrification cycle as the flue gas enters the pipe, executes a first-order reducing agent delivery decision based on the flue gas flow rate, and performs a second-order decoupling decision and strategy coupling based on the denitrification controller to determine the injection strategy and introduce tracer medium simulation verification. The denitrification cycle is progressively divided into sections according to the pipeline, with the NOx concentration limit as the processing standard. This achieves the technical effect of dynamically optimizing the injection strategy, improving the denitrification efficiency and reducing agent utilization rate.

Description

Technical Field

[0001] The present invention relates to the technical field of flue gas denitration, and in particular to a flue gas denitration reducing agent precise injection control system based on flow feedback. Background Art

[0002] Traditional denitrification systems typically employ a single-point or fixed-point injection strategy, injecting a reducing agent (such as ammonia or urea) into the flue gas duct to chemically react with NOx in the flue gas, converting it into nitrogen and water. However, existing technologies often rely on empirical or fixed-point deployment of injection points, lacking real-time feedback on dynamic changes in NOx concentration within the flue gas duct. This makes it difficult to precisely match the reducing agent injection amount and location to actual needs. Summary of the Invention

[0003] The present invention provides a precise injection control system for flue gas denitrification reducing agents based on flow feedback to solve the technical problems in the prior art of single injection point deployment, difficulty in coping with complex situations, and unstable denitrification effect, thereby achieving the technical effect of dynamically optimizing the injection strategy, improving the denitrification efficiency and reducing agent utilization rate.

[0004] The present invention provides a flue gas denitrification reducing agent precise injection control system based on flow feedback, comprising:

[0005] The smoke duct staging module is used to divide the smoke duct into sections and deploy multi-point injection during the denitration cycle based on the NOx concentration at the duct outlet, thereby constructing a cascade denitration structure. Each section has a decreasing limit based on the NOx concentration.

[0006] The control establishment module is used to mathematically reconstruct the cascade denitrification structure, build a denitrification controller with the goal of multivariable decoupling decision and tracer simulation of flue gas denitrification, wherein the denitrification controller is connected to the front-end device deployed in the smoke flow pipeline based on a network protocol.

[0007] The injection decision module is used to trigger the denitration control cycle as flue gas enters the pipe. It makes a first-order linear decision on the amount of reducing agent to be injected based on the flue gas flow rate, performs a second-order decoupling decision and strategy coupling based on the denitration controller, determines the injection strategy, introduces a tracer medium for simulation verification, and outputs the injection control strategy. The denitration control cycle is a progressive multi-round process based on the flue gas pipe segment, with the NOx concentration of the zone limit as the zone treatment standard.

[0008] In a feasible implementation method, the execution steps of the smoke flow pipeline stage module include: the NOx concentration at the pipeline outlet is used as the denitrification separation standard, the inlet and outlet ends of the smoke flow pipeline are used as the NOx separation period, and the pipeline partitioning in the smoke flow direction corresponds to multiple denitrification separation stages.

[0009] In a feasible implementation, the smoke duct stage module includes:

[0010] The denitrification pipeline section unit is used to determine the denitrification pipeline section according to the reduction reaction time of the reducing agent injection and the smoke flow velocity range.

[0011] The partition deployment unit is used to partition the smoke flow pipeline with the denitrification pipeline section as the separation stage constraint, wherein at least one position of each partition is deployed with an injection device.

[0012] In a feasible implementation, the injection decision module includes:

[0013] The first-order linear decision-making unit is used to determine the proxy linear relationship with the flue gas flow rate as the independent variable and the reducing agent input amount as the dependent variable.

[0014] The flow detection unit is used to detect the smoke flow at the inlet of the smoke flow duct.

[0015] The linear decision-making unit is used to make a linear decision on the reducing agent input amount for the flue gas flow according to the agent linear relationship, and determine a first-order strategy.

[0016] In a feasible implementation, the execution steps of the flow detection unit include: deploying a flow meter at the inlet of the smoke duct, and performing flow detection on the inlet smoke based on the flow meter at preset time nodes as batches.

[0017] In a feasible implementation, the injection decision module includes:

[0018] The coupling variable determination unit is used to determine the coupling variables of flue gas denitrification, wherein the coupling variables at least include NOx concentration, ammonia escape rate, and flue gas temperature.

[0019] The sensor data receiving unit is used to introduce the first-order strategy into the denitration controller and receive sensor data from the front-end device, wherein the sensor data at least includes flue gas composition and flue gas temperature.

[0020] The multivariable decoupling decision unit is used to perform multivariable decoupling decision-making according to the sensor data and the first-order strategy to determine a strategy group.

[0021] The strategy group coupling unit is used to couple the strategy groups and determine the injection control strategy.

[0022] In a feasible implementation, the execution steps of the strategy group coupling unit include: determining a multivariable decoupling method and temporarily storing it, and reversely coupling the strategy group according to the multivariable decoupling method.

[0023] In a feasible implementation, the policy group coupling unit includes:

[0024] The initialization strategy subunit is used to couple the strategy groups and determine the initialization strategy.

[0025] The tracer simulation subunit is used to introduce a tracer medium, perform tracer simulation on the initialization strategy, and determine the injection control strategy, which at least includes an injection angle, an injection rate, and an injection intensity.

[0026] In a feasible implementation, the policy group coupling unit further includes:

[0027] The guide component deployment subunit is used to deploy the smoke flow guide component and establish working condition coordination between the smoke flow guide component and the injection device.

[0028] The simulation effect identification subunit is used to identify the tracer simulation effect and determine whether the balanced relaxation degree is met. If not, it coordinates the angle control of the smoke flow guide component and the injection device to perform optimization adjustment and determine the injection control strategy.

[0029] In a feasible implementation, the injection decision module includes:

[0030] The cycle execution unit is used to execute the injection control strategy and complete the injection control of the first cycle stage.

[0031] The retrospective evaluation unit is used to trigger the front-end device to obtain sensor data when the flow is transferred to the second partition port, perform a first cycle stage evaluation, and determine a first evaluation coefficient.

[0032] The dual-stage compensation decision unit is used to perform dual-stage decision making and drive the injection device to perform denitration control based on the NOx concentration of the second partition as a processing standard and the first evaluation coefficient as compensation processing.

[0033] The present invention discloses a precise injection control system for flue gas denitrification reducing agents based on flow feedback, comprising: a flue gas duct staging module that performs segmented staging and multi-point injection deployment on the flue gas duct, takes the NOx concentration at the duct outlet end as a constraint, forms a cascade denitrification structure, and sets a decreasing limit based on the NOx concentration in each partition; a control establishment module mathematically reconstructs the cascade denitrification structure, constructs a denitrification controller with the multivariable decoupling decision and tracer simulation of flue gas denitrification as the goal, and connects it to the front-end device of the flue gas duct through a network protocol; an injection decision module triggers a denitrification control cycle as the flue gas enters the duct, executes a first-order linear decision on the reducing agent input amount according to the flue gas flow, and performs a second-order decoupling decision and strategy coupling in combination with the denitrification controller, finally determines the injection strategy, introduces a tracer medium for simulation verification, and completes the denitrification treatment progressively with the segment limit of the NOx concentration as the standard. The flow feedback-based flue gas denitrification reducing agent precise injection control system disclosed in the present invention solves the technical problems of single injection point deployment, difficulty in coping with complex situations, and unstable denitrification effect, and achieves the technical effect of dynamically optimizing the injection strategy, improving the denitrification efficiency and reducing agent utilization rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of the flue gas denitrification reducing agent precise injection control system based on flow feedback of the present invention.

[0035] Figure 2 It is a structural schematic diagram of the injection decision module in the flue gas denitrification reducing agent precise injection control system based on flow feedback of the present invention.

[0036] Explanation of the reference numerals: smoke flow duct staging module 11 , control establishment module 12 , injection decision module 13 , first-order linear decision unit 131 , flow detection unit 132 , linear decision unit 133 . DETAILED DESCRIPTION

[0037] The above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods of the specification to better understand the above technical solution. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments of the present invention. It should be understood that the present invention is not limited to the example embodiments used only to explain the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. In addition, it should be noted that, for the convenience of description, only the parts related to the present invention, rather than all, are shown in the drawings.

[0038] Example, Figure 1 The structure diagram of the flue gas denitrification reducing agent precise injection control system based on flow feedback of the present invention is shown in FIG. The flue gas denitrification reducing agent precise injection control system based on flow feedback includes:

[0039] The smoke duct staging module 11 is used to divide the smoke duct into sections and deploy multi-point injection for the denitration cycle based on the NOx concentration at the duct outlet, so as to build a cascade denitration structure, in which each section has a decreasing limit based on the NOx concentration.

[0040] Specifically, the flue gas duct staging module divides the flue gas duct into multiple sections based on NOx concentration distribution patterns. Injection devices are deployed in each section to form a cascaded denitrification structure. The NOx concentration limit for each section decreases gradually along the flue gas flow, ensuring a progressively optimized denitrification process.

[0041] The above steps help to improve the matching degree between the injection amount and position of the reducing agent and the actual NOx concentration distribution by deploying the injection device in stages, thereby improving the utilization rate of the reducing agent and reducing the risk of local overinjection.

[0042] In some embodiments, the execution steps of the smoke flow pipe staging module 11 include: the NOx concentration at the pipe outlet is used as the denitrification separation standard, the inlet and outlet ends of the smoke flow pipe are used as the NOx separation period, and the pipe division in the smoke flow direction corresponds to multiple denitrification separation stages.

[0043] Specifically, the distance from the inlet to the outlet of the smoke flow duct is regarded as a complete NOx separation cycle. At the same time, the duct in the direction of the smoke flow is divided into multiple sections, each section corresponding to a denitrification treatment stage. Among them, multiple denitrification separation stages can be grouped based on the NOx concentration change law or the arrangement of the injection points.

[0044] Through the above definition, the system can dynamically adjust the injection strategy to ensure that the NOx concentration in each section is gradually reduced, ultimately achieving the NOx concentration target at the outlet. This staged design can adapt to dynamic changes in flue gas flow and NOx concentration, avoiding local over- or under-injection problems caused by single-point injection.

[0045] In some embodiments, the smoke duct staging module 11 includes:

[0046] The denitrification pipeline section unit is used to determine the denitrification pipeline section according to the reduction reaction time of the reducing agent injection and the smoke flow velocity range.

[0047] The partition deployment unit is used to partition the smoke flow pipeline with the denitrification pipeline section as the separation stage constraint, wherein at least one position of each partition is deployed with an injection device.

[0048] Specifically, the reduction reaction time is the time required for the reducing agent (such as ammonia or urea) to chemically react with NOx in the flue gas; the flue gas flow velocity range refers to the range of flue gas flow velocities in the pipeline, among which the flue gas flow velocity significantly affects the mixing efficiency of the reducing agent and flue gas.

[0049] Specifically, first, based on the chemical properties of the reducing agent and the reaction conditions of the denitrification environment (such as flue gas temperature), the time required for the reducing agent to react with NOx (i.e., the reduction reaction time) is calculated; at the same time, sensors or other monitoring equipment (such as pitot tubes) are activated to collect smoke flow velocity data in the pipeline and determine the flow velocity range; then, combined with the reduction reaction time and smoke flow velocity range, the length and position of each section are calculated to ensure that the reducing agent entering the section can be fully mixed with the flue gas and fully react within the section.

[0050] Furthermore, according to the division result of the denitrification pipeline section, the smoke flow pipeline is divided into multiple sections, and a reducing agent injection device (such as an inlet or middle position) is deployed in each partition, wherein each section corresponds to a denitrification separation stage.

[0051] Through the above process, the precise staging of the smoke flow duct and the reasonable deployment of the injection device are achieved, which is not only conducive to improving the utilization rate of the reducing agent, but also helps to enhance the dynamic adaptability of the system and ensure the stability and reliability of the denitrification effect.

[0052] The control establishment module 12 is used to mathematically reconstruct the cascade denitrification structure, build a denitrification controller with the goal of multivariable decoupling decision and tracer simulation of flue gas denitrification, wherein the denitrification controller is connected to the front-end device deployed in the smoke flow pipeline based on a network protocol.

[0053] Specifically, the control establishment module 12 mathematically models the cascade denitrification structure, that is, based on a mathematical model (such as a set of reaction kinetic differential equations), the denitrification process is abstracted into an optimization problem with multiple variables (including NOx concentration, flow rate, temperature, reducing agent concentration, reaction time, etc.).

[0054] Specifically, multivariable decoupling decision-making involves breaking down complex denitrification control problems into multiple independent variables (such as NOx concentration, flue gas flow rate, and temperature) to optimize their respective decisions. Tracer simulation involves introducing a tracer medium (e.g., simulated flue gas composition) to verify the effectiveness of injection strategies. This involves connecting front-end devices (such as sensors and injection devices) via network protocols to acquire real-time data on flue gas composition and temperature. This data is then combined with first-order linear decision-making results to execute multivariable decoupling decision-making.

[0055] Exemplarily, multivariable decoupling decision-making is achieved through methods such as model predictive control or linear quadratic regulator; the denitrification controller is connected to the front-end device through standard industrial protocols (such as Modbus TCP, OPC UA, etc.) to achieve remote parameter distribution and data feedback.

[0056] Through mathematical modeling and multivariable decoupling, the aforementioned process decomposes abstract tasks into a concrete, dynamic optimization solution for multiple indicators, thereby improving decision-making efficiency and facilitating adaptation to complex operating conditions. Furthermore, tracer simulation verifies the effectiveness of injection strategies before implementation, preventing unstable denitrification results caused by strategic errors.

[0057] The injection decision module 13 is used to trigger the denitration control cycle as flue gas enters the pipe. It makes a first-order linear decision on the amount of reducing agent to be injected based on the flue gas flow rate, performs a second-order decoupling decision and strategy coupling based on the denitration controller, determines the injection strategy, introduces a tracer medium for simulation verification, and outputs the injection control strategy. The denitration control cycle is a progressive multi-round process performed in stages based on the flue gas pipe segment, with the NOx concentration at the zone limit as the zone treatment standard.

[0058] Specifically, the first-order linear decision is a preliminary injection quantity estimation decision based on the relationship between the flue gas flow rate and the reducing agent input amount; the second-order decoupling decision is a further optimization of the injection strategy based on the preliminary injection strategy combined with the multivariable decoupling decision, and by introducing a multivariable structural process, it can more comprehensively reflect the actual out-of-stock environment; further, strategy coupling is the process of integrating multiple optimization strategies into the final injection control strategy, which helps to ensure the stability and reliability of the injection effect.

[0059] This process, through multiple rounds of progressive optimization, optimizes the injection strategy, facilitating dynamic adjustment of injection volume and location (i.e., rapid second-order decision-making based on first-order decisions), improving reductant utilization, and ensuring the stability and reliability of denitrification. Furthermore, the introduction of a tracer simulation verification mechanism helps ensure the reliability of the injection strategy, avoiding unstable denitrification due to strategy errors.

[0060] In some embodiments, as Figure 2 As shown, the injection decision module 13 includes:

[0061] The first-order linear decision unit 131 is used to determine a proxy linear relationship using the flue gas flow rate as an independent variable and the reducing agent input amount as a dependent variable.

[0062] The flow detection unit 132 is used to detect the smoke flow at the inlet of the smoke flow duct.

[0063] The linear decision unit 133 is configured to perform a linear decision on the reducing agent input amount for the flue gas flow rate according to the proxy linear relationship, and determine a first-order strategy.

[0064] Specifically, the first-order linear decision-making unit 131 obtains historical or online data, uses flue gas flow rate as the independent variable and reducing agent input amount as the dependent variable, and then fits and determines a proxy linear relationship between the two. This proxy linear relationship is a relatively universal concentration relationship determined based on statistics, which provides a mathematical model basis for subsequent decision-making. For example, the slope and intercept are obtained by performing statistical analysis or least squares fitting on flue gas flow rate and reducing agent input amount data under multiple operating conditions.

[0065] Specifically, the flow detection unit 132 detects and collects the flue gas flow data in real time through a flow sensor installed at the entrance of the smoke duct; the linear decision unit 133 is based on the flue gas flow data collected by the above-mentioned flow detection unit 132 and the linear proxy relationship determined by the first-order linear decision unit 131, and obtains the reducing agent input amount recommended in the first-order strategy by bringing the flue gas flow data into the proxy linear relationship for calculation.

[0066] The above-mentioned linear decision-making method helps to achieve rapid response and real-time control, ensuring that the system's dosing decisions under various working conditions have a certain degree of predictive accuracy and real-time performance.

[0067] In some implementations, the execution step of the flow detection unit includes: deploying a flow meter at the inlet of the smoke duct, and performing flow detection on the inlet smoke based on the flow meter at preset time nodes as batches.

[0068] Specifically, the flow meter is used to measure the flow rate of a fluid (such as flue gas) (such as a Pitot tube); the preset time node is a pre-set time interval for collecting flow data in batches.

[0069] Specifically, first install a flow meter at the entrance of the smoke duct to ensure that it can accurately measure the flow of the smoke entering the duct. At the same time, according to the system requirements and working conditions, pre-set the time nodes for flow detection (such as every minute, every hour, etc.). The higher the monitoring requirements, the shorter the corresponding time interval; then, activate the flow meter to collect smoke flow data in batches according to the preset time nodes, and transmit the data to the injection decision module.

[0070] In some embodiments, the injection decision module 13 includes:

[0071] The coupling variable determination unit is used to determine the coupling variables of flue gas denitrification, wherein the coupling variables at least include NOx concentration, ammonia escape rate, and flue gas temperature.

[0072] The sensor data receiving unit is used to introduce the first-order strategy into the denitration controller and receive sensor data from the front-end device, wherein the sensor data at least includes flue gas composition and flue gas temperature.

[0073] The multivariable decoupling decision unit is used to perform multivariable decoupling decision-making according to the sensor data and the first-order strategy to determine a strategy group.

[0074] The strategy group coupling unit is used to couple the strategy groups and determine the injection control strategy.

[0075] Specifically, the coupling variables of flue gas denitrification are multiple variables that affect the flue gas denitrification effect, and there is mutual influence between the variables.

[0076] Specifically, a first-order strategy (with a preliminary injection volume estimate) is imported into the denitrification controller. Simultaneously, real-time sensor data collected by front-end devices (such as NOx sensors and temperature sensors) is imported into the denitrification controller. This sensor data includes at least flue gas composition and temperature. The sensor data and first-order strategy are then decomposed into multiple independent variables. An optimization decision is then made for each independent variable, generating multiple strategy groups. For example, the injection volume can be adjusted based on NOx concentration, or the injection angle can be adjusted based on flue gas temperature. Once the optimization is complete, the multiple strategy groups are combined into a final injection control strategy output, guiding the injection device to execute precise injection.

[0077] The above process, through multi-variable decoupling decision-making, helps to optimize each variable separately, thereby improving the accuracy of the injection strategy; among them, the fusion action of the strategy group coupling unit ensures the coordination between multiple strategies and avoids the instability of the injection effect caused by variable conflicts.

[0078] In some implementations, the execution step of the strategy group coupling unit includes: determining a multi-variable decoupling method and temporarily storing it, and reversely coupling the strategy group according to the multi-variable decoupling method.

[0079] Specifically, multivariable decoupling refers to a method of decomposing complex coupled variables into independent variables. Available multivariable decoupling methods include: relative gain matrix (RGA), inverse decoupling control, etc.; inverse coupling is the process of recombining independent variables into an overall control strategy after decoupling, which is used to ensure the coordination between the variables.

[0080] In some implementations, the policy group coupling unit includes:

[0081] The initialization strategy subunit is used to couple the strategy groups and determine the initialization strategy.

[0082] The tracer simulation subunit is used to introduce a tracer medium, perform tracer simulation on the initialization strategy, and determine the injection control strategy, which at least includes an injection angle, an injection rate, and an injection intensity.

[0083] Specifically, the initialization strategy subunit is primarily used to couple and integrate multiple strategy groups to determine an initial dosing or control strategy (initialization strategy) based on preset rules or initial settings. Optionally, the preset rules or initial settings are determined based on collected historical data, operating parameters, and environmental variables.

[0084] Specifically, the tracer simulation subunit dynamically simulates the aforementioned initialization strategy by introducing a tracer medium. This simulation, implemented through physical modeling and numerical simulation techniques, captures the diffusion, mixing, and reaction of the tracer medium during the actual injection process in real time, providing data support for further optimizing and adjusting control parameters to determine a more accurate injection control strategy that meets actual needs.

[0085] Specifically, the injection control strategy includes at least: injection angle, which determines the direction and range of the added medium entering the target area; injection rate, which adjusts the medium addition acceleration according to real-time flow or concentration requirements; and injection intensity, which reflects the impact force or diffusion effect generated by the medium during the injection process to ensure that the predetermined treatment efficiency is achieved.

[0086] Through the above implementation method, reasonable control schemes and tracer simulation feedback are quickly generated based on initial data, which enables the injection control strategy to be continuously improved and optimized to better adapt to actual operating conditions.

[0087] In some implementations, the policy group coupling unit further includes:

[0088] The guide component deployment subunit is used to deploy the smoke flow guide component and establish working condition coordination between the smoke flow guide component and the injection device.

[0089] The simulation effect identification subunit is used to identify the tracer simulation effect and determine whether the balanced relaxation degree is met. If not, it coordinates the angle control of the smoke flow guide component and the injection device to perform optimization adjustment and determine the injection control strategy.

[0090] Specifically, the smoke flow guiding component is a device for adjusting the direction and speed of smoke flow, and is used to optimize the gas flow state in the flue to ensure that the reducing agent and the smoke are fully mixed. The smoke flow guiding component is capable of coordinating with the working conditions of the injection device, that is, it can be adaptively adjusted according to the working state of the injection device, thereby ensuring a good mixing effect under different injection conditions. For example, the above-mentioned working condition coordination is determined based on experiments or simulation experiments.

[0091] Specifically, the simulation effect identification subunit is used to identify the effect of the tracer simulation, determine whether the equilibrium relaxation is met, and perform optimization adjustments when necessary, where the equilibrium relaxation refers to the error range allowed for the injection strategy when meeting the denitrification target.

[0092] Specifically, the tracer simulation results are identified to determine whether they meet the equilibrium relaxation requirement. If the tracer results do not meet the equilibrium relaxation requirement, the smoke flow guide assembly and the injection device angle are simultaneously optimized for coordinated control, thereby ensuring a more balanced medium distribution and reaction during the actual injection process. Optionally, this coordinated control optimization is implemented based on the same method and principles as the tracer simulation, that is, a simulation-based coordinated control optimization.

[0093] In some embodiments, the injection decision module 13 includes:

[0094] The cycle execution unit is used to execute the injection control strategy and complete the injection control of the first cycle stage.

[0095] The retrospective evaluation unit is used to trigger the front-end device to obtain sensor data when the flow is transferred to the second partition port, perform a first cycle stage evaluation, and determine a first evaluation coefficient.

[0096] The dual-stage compensation decision unit is used to perform dual-stage decision making and drive the injection device to perform denitration control based on the NOx concentration of the second partition as a processing standard and the first evaluation coefficient as compensation processing.

[0097] Specifically, during the preset first cycle stage, the cycle execution unit is responsible for controlling the injection angle, rate and intensity according to the determined injection control strategy to achieve stable continuous injection; when the flue gas or working condition flows to the second partition port (i.e., the second partition entrance), the retrospective evaluation unit is started to evaluate the injection control effect of the first cycle stage, including triggering the front-end device at the second partition port to obtain relevant sensor data (such as flue gas composition, NOx concentration, etc.), and calculating and determining the first evaluation coefficient based on the degree of deviation between the acquired sensor data and the theoretical expected data. The first evaluation coefficient reflects the execution effect and deviation degree of the injection control strategy in the current cycle.

[0098] Furthermore, using the NOx concentration in the second zone as the key process indicator, the control effect of the first cycle is compensated based on the first evaluation coefficient. For example, if the first evaluation coefficient indicates poor performance during the first cycle, the reductant injection rate and mixing intensity in the second zone are increased based on the first evaluation coefficient. The compensation decision-making unit implements a two-stage decision-making process, ensuring that injection device adjustments take into account both real-time data feedback and historical evaluation results, thereby achieving more accurate denitration control in the next cycle.

[0099] The above-mentioned phased optimization and dynamic compensation mechanism helps ensure that the denitrification effect in the next stage is optimal, thereby gradually reducing the NOx concentration and ultimately achieving the denitrification target at the outlet end, while improving the utilization rate of the reducing agent and the overall stability of the system.

[0100] In summary, the flue gas denitrification reducing agent precise injection control system based on flow feedback provided by the present invention has the following technical effects:

[0101] The smoke duct stage module is used to segment the smoke duct and deploy multi-point injection. The NOx concentration at the duct outlet is used as a constraint to form a cascade denitrification structure, and a decreasing limit based on the NOx concentration is set in each zone. The control establishment module mathematically reconstructs the cascade denitrification structure, and builds a denitrification controller with the goal of multivariable decoupling decision and tracer simulation of flue gas denitrification, and connects it to the front-end device of the smoke duct through a network protocol. The injection decision module triggers the denitrification control cycle as the smoke enters the pipe, executes a first-order linear decision on the reducing agent input amount according to the smoke flow rate, and combines the denitrification controller for second-order decoupling decision and strategy coupling to finally determine the injection strategy, and introduces a tracer medium for simulation verification. Taking the segment limit of NOx concentration as the standard, the denitrification treatment is completed progressively, thereby achieving the technical effect of dynamically optimizing the injection strategy, improving the denitrification efficiency and the reducing agent utilization rate.

[0102] It should be understood that the embodiments disclosed in the present invention and the above description can enable those skilled in the art to use the present invention to implement the present invention. At the same time, the present invention is not limited to the embodiments mentioned above. It should be understood that those skilled in the art can still modify the technical solutions described in the above embodiments or replace some of the technical features therein with equivalents; and such modifications or replacements do not deviate from the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention and are all included in the scope of protection of the present invention.

Claims

1. Flue gas denitrification reducing agent precise injection control system based on flow feedback, characterized by: include: The flue gas duct staging module is used to divide the flue gas duct into sections and deploy multi-point injection for the denitration cycle based on the NOx concentration at the duct outlet, thus building a cascade denitration structure. Each section has a decreasing limit based on the NOx concentration. a control establishment module for mathematically reconstructing the cascade denitrification structure, constructing a denitrification controller with the goal of multivariable decoupling decision-making and tracer simulation of flue gas denitrification, wherein the denitrification controller is connected to the front-end device deployed in the flue gas duct based on a network protocol; The injection decision module is used to trigger the denitration control cycle as the flue gas enters the pipe, make a first-order linear decision on the amount of reducing agent to be added based on the flue gas flow rate, perform a second-order decoupling decision and strategy coupling based on the denitration controller, determine the injection strategy, introduce a tracer medium for simulation verification, and output the injection control strategy. The denitration control cycle is a progressive multi-round process based on the flue gas pipe segment, with the NOx concentration of the zone limit as the zone treatment standard. Wherein, the injection decision module includes: A cycle execution unit, configured to execute the injection control strategy and complete the injection control in the first cycle stage; A retrospective evaluation unit is configured to trigger a front-end device to acquire sensor data, perform a first cycle phase evaluation, and determine a first evaluation coefficient when the flow is transferred to the second partition port; The dual-stage compensation decision unit is used to perform dual-stage decision making and drive the injection device to perform denitration control based on the NOx concentration of the second partition as a processing standard and the first evaluation coefficient as compensation processing.

2. The flue gas denitrification reducing agent precise injection control system based on flow feedback according to claim 1, characterized in that: The execution steps of the smoke flow pipeline stage module include: the NOx concentration at the pipeline outlet is used as the denitration separation standard, the inlet and outlet ends of the smoke flow pipeline are used as the NOx separation period, and the pipeline partitioning in the smoke flow direction corresponds to multiple denitration separation stages.

3. The flue gas denitrification reducing agent precise injection control system based on flow feedback according to claim 2, characterized in that: The smoke duct stage module includes: The denitration pipeline section unit is used to determine the denitration pipeline section according to the reduction reaction time of the reducing agent injection and the smoke flow velocity range; The partition deployment unit is used to partition the smoke flow pipeline with the denitrification pipeline section as the separation stage constraint, wherein at least one position of each partition is deployed with an injection device.

4. The flue gas denitrification reducing agent precise injection control system based on flow feedback according to claim 1, characterized in that: The injection decision module includes: The first-order linear decision-making unit is used to determine the proxy linear relationship with the flue gas flow rate as the independent variable and the reducing agent input as the dependent variable; A flow detection unit, used to detect the smoke flow at the inlet of the smoke flow duct; The linear decision-making unit is used to make a linear decision on the reducing agent input amount for the flue gas flow according to the agent linear relationship, and determine a first-order strategy.

5. The flue gas denitrification reducing agent precise injection control system based on flow feedback according to claim 4, characterized in that: The execution steps of the flow detection unit include: deploying a flow meter at the inlet of the smoke duct, and performing flow detection on the inlet smoke based on the flow meter at preset time nodes as batches.

6. The flue gas denitrification reducing agent precise injection control system based on flow feedback according to claim 5, characterized in that: The injection decision module includes: A coupling variable determination unit, configured to determine coupling variables for flue gas denitrification, wherein the coupling variables include at least NOx concentration, ammonia escape rate, and flue gas temperature; a sensor data receiving unit, configured to introduce the first-order strategy into the denitration controller and receive sensor data from a front-end device, wherein the sensor data at least includes flue gas composition and flue gas temperature; a multivariable decoupling decision unit, configured to perform multivariable decoupling decision making and determine a strategy group based on the sensor data and the first-order strategy; The strategy group coupling unit is used to couple the strategy groups and determine the injection control strategy.

7. The flue gas denitrification reducing agent precise injection control system based on flow feedback according to claim 6, characterized in that: The execution steps of the strategy group coupling unit include: determining a multi-variable decoupling method and temporarily storing it, and reversely coupling the strategy group according to the multi-variable decoupling method.

8. The flue gas denitrification reducing agent precise injection control system based on flow feedback according to claim 7, characterized in that: The strategy group coupling unit includes: an initialization strategy subunit, configured to couple the strategy groups and determine an initialization strategy; The tracer simulation subunit is used to introduce a tracer medium, perform tracer simulation on the initialization strategy, and determine the injection control strategy, which at least includes an injection angle, an injection rate, and an injection intensity.

9. The flue gas denitrification reducing agent precise injection control system based on flow feedback according to claim 8, characterized in that: The strategy group coupling unit further includes: A guide component deployment subunit, used to deploy the smoke flow guide component and establish working condition coordination between the smoke flow guide component and the injection device; The simulation effect identification subunit is used to identify the tracer simulation effect and determine whether the balanced relaxation degree is met. If not, it coordinates the angle control of the smoke flow guide component and the injection device to perform optimization adjustment and determine the injection control strategy.

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