Efficient dust and nitrate integrated SCR denitration system and method in high-temperature and low-dust environment

Abstract

The invention relates to the technical field of flue gas denitration, and discloses an efficient dust and nitrate integrated SCR denitration system and method in a high-temperature and low-dust environment. A lower high-temperature dust removal unit containing a gradient three-dimensional porous metal fiber filtering element and an upper SCR denitration reactor located at the downstream of the lower high-temperature dust removal unit containing a multi-layer vanadium-titanium honeycomb type catalyst module are arranged in the upper SCR denitration reactor; the ammonia spraying module sprays ammonia to the upstream or the interior of the SCR reactor; and the intelligent control module controls the ammonia spraying and dust removal unit to remove dust, comprises a catalyst characteristic identification sub-module, a working condition disturbance prediction sub-module and a collaborative optimization control sub-module, and realizes an optimization decision of a final ammonia spraying instruction. High-temperature dust removal and SCR denitration are integrated in the integrated box body, so that the compactness of the system structure is realized; front efficient dust removal provides a clean flue gas environment for the catalyst, the service life of the catalyst is effectively prolonged, and the denitration efficiency is guaranteed; and the intelligent control module ensures the accuracy and self-adaption of ammonia spraying operation, and the removal rate of nitrogen oxides and the operation economy are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of flue gas denitrification, and in particular to a high-efficiency dust and nitrate integrated SCR denitrification system and method under a high-temperature and low-dust environment. Background Art

[0002] Industrial high-temperature production processes, such as those in the cement and metallurgical industries, often produce flue gas emissions characterized by high temperatures, dust levels, and high concentrations of nitrogen oxides (NOx), posing a significant threat to the atmospheric environment. With increasingly stringent environmental standards, the development of compact, intelligent purification technologies that can efficiently and synergistically control multiple pollutants in these flue gases has become a key industry priority.

[0003] Existing technologies typically purify high-temperature, dusty flue gas using separate, cascaded units. The flue gas first passes through independent high-temperature dust removal equipment (such as a high-temperature bag filter) to remove particulate matter. The flue gas then enters a selective catalytic reduction (SCR) denitrification reactor at an appropriate temperature, where ammonia injection reduces NOx over the catalyst. In some systems, ammonia injection control may rely on feedback from outlet NOx concentrations or simplified feedforward estimates.

[0004] However, such traditional solutions still have shortcomings when dealing with complex operating conditions. First, the separate arrangement of dust removal and denitrification units results in a large system footprint, complex piping, high investment and maintenance costs, and the possibility of heat loss. Crucially, if the pre-dust removal efficiency is insufficient or unstable, residual dust enters the SCR reactor, causing catalyst wear, blockage, and poisoning and deactivation, significantly shortening its life and affecting denitrification efficiency. In addition, traditional ammonia injection control is difficult to accurately adapt to operating condition fluctuations and catalyst activity attenuation, which can easily lead to NOx exceeding the standard or ammonia escape, making it difficult to achieve refinement and economy of the denitrification process.

[0005] Therefore, the present invention proposes a high-efficiency dust and nitrate integrated SCR denitrification system and method under a high-temperature and low-dust environment to address the deficiencies of the existing technology. Summary of the Invention

[0006] In response to the shortcomings of the existing technology, the present invention provides a high-efficiency integrated dust and nitrate SCR denitrification system and method in a high-temperature and low-dust environment, which solves the problems that traditional flue gas purification systems occupy a large area, the catalyst is easily deactivated by dust, and the ammonia injection control accuracy is not high, making it difficult to strike a balance between denitrification efficiency and economy.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions: a high-efficiency dust and nitrate integrated SCR denitrification system in a high-temperature and low-dust environment, including an integrated box, wherein the following are integrated in the integrated box: a high-temperature dust removal unit for removing dust from high-temperature flue gas from an industrial production device that generates flue gas, the high-temperature dust removal unit being located at the lower portion of the integrated housing and comprising a flue gas inlet, an airflow distribution device, and a filter element having a gradient three-dimensional porous metal fiber structure, and an ash hopper located below the filter element, the filter element being used to collect dust removed by the filter element; An SCR denitration reactor is used to perform a denitration reaction on the clean, high-temperature flue gas after dust removal to control the nitrogen oxide emission concentration below a predetermined target value. The treated flue gas is discharged from the upper flue gas outlet. The SCR denitration reactor is located at the upper part of the integrated housing and downstream of the high-temperature dust removal unit, and includes a multi-layered SCR catalyst module; a vanadium-titanium honeycomb SCR catalyst is installed in the SCR catalyst module; an ammonia injection module, for injecting an ammonia-containing reducing agent into the flue gas upstream of or inside the SCR denitration reactor through a spray gun; An intelligent control module is used to control the ammonia injection operation of the ammonia injection module and the dust cleaning operation of the high-temperature dust removal unit. The intelligent control module includes: a catalyst characteristic identification module for online identification of reaction characteristics of the SCR catalyst and determining basic settings for controlling ammonia injection based on the reaction characteristics; an operating condition disturbance prediction module for identifying an operating condition mode of the industrial production device generating flue gas, predicting an expected disturbance of the flue gas at the inlet of the SCR denitrification reactor, and determining forward-looking compensation information for adjusting ammonia injection based on the disturbance; The collaborative optimization control module is configured to evaluate the output of the catalyst characteristic identification module and the output of the operating condition disturbance prediction module, and determine the final ammonia injection control instruction through adaptive weight fusion and multi-objective collaborative decision-making.

[0008] Preferably, the air flow distribution device is located downstream of the flue gas inlet of the high-temperature dust removal unit and upstream of the filter element. The air flow distribution device is used to make the flue gas flow velocity and flow rate entering the filter element uniformly distributed. The air flow distribution device is a porous plate.

[0009] Preferably, the integrated box is arranged vertically, the flue gas inlet of the high-temperature dust removal unit is located on the side outside the integrated box, and the clean high-temperature flue gas after dust removal flows vertically upward from the high-temperature dust removal unit into the SCR denitrification reactor. The pressure resistance of the SCR denitrification reactor is ±8000Pa.

[0010] Preferably, the filter element is a high-temperature metal filter bag, and the high-temperature dust removal unit also includes an online pulse jet cleaning system, which is used to remove dust attached to the high-temperature metal filter bag. The online pulse jet cleaning system uses compressed air of 0.4MPa to 0.5MPa for spraying, and the intelligent control module starts the online pulse jet cleaning system when the pressure difference on both sides of the high-temperature metal filter bag is greater than -7kPa.

[0011] Preferably, the SCR catalyst modules in the SCR denitration reactor have an interlayer spacing of 1.2 m, and the SCR catalyst modules are arranged in a 6×7 modular arrangement; the SCR denitration reactor is contained in a shell made of Q355B heat-resistant steel with a thickness of 6 mm and provided with an external insulation layer with a total thickness of 300 mm, and the insulation layer includes a 200 mm thick aluminum silicate needle-punched blanket and a 100 mm thick rock wool.

[0012] Preferably, the ammonia injection module includes at least one ammonia spray gun arranged in the inlet flue of the SCR denitrification reactor, the ammonia spray gun is connected to a control valve for adjusting the flow of the ammonia-containing reducing agent, and the ammonia-containing reducing agent injection is started by the instruction of the intelligent control module.

[0013] Preferably, the catalyst characteristic identification module collects and analyzes online the data of at least the flue gas composition, temperature and catalyst bed pressure drop at the inlet and outlet of the SCR denitrification reactor, and combines a preset catalyst kinetic model or historical data trend to periodically evaluate the current activity level, blockage degree or expected remaining life of the vanadium-titanium honeycomb SCR catalyst to dynamically correct the basic settings of the ammonia spray gun.

[0014] Preferably, the operating condition disturbance prediction module identifies the operating condition mode of the industrial production equipment that generates flue gas by constructing a clustering algorithm of 5 to 15 typical operating condition mode libraries, and predicts the expected disturbance of the flue gas at the inlet of the SCR denitrification reactor in the next 5 to 30 minutes; the update cycle of the operating condition disturbance prediction module is 1 to 5 minutes.

[0015] Preferably, the collaborative optimization control module uses fuzzy logic control or a rule-based expert system to perform multi-objective collaborative decision-making to determine the final ammonia injection control instruction; the update cycle of the collaborative optimization control module is 1 to 10 seconds.

[0016] The present invention also provides a high-efficiency dust and nitrate integrated SCR denitrification method under a high-temperature and low-dust environment, comprising the following steps: High-temperature flue gas from industrial production equipment is introduced into the integrated box and subjected to primary dust removal treatment by the high-temperature dust removal unit at the bottom of the integrated box; The high-temperature flue gas first passes through an air flow distribution device located downstream of the flue gas inlet and upstream of the filter element to uniformly distribute the flow velocity and flow rate; The flue gas after the airflow is evenly distributed enters the filter element with a gradient three-dimensional porous metal fiber structure arranged in the high-temperature dust removal unit to intercept high-temperature particulate matter. The filter element is preferably a high-temperature metal filter bag; When the pressure difference on both sides of the high-temperature metal filter bag exceeds the preset threshold, the intelligent control module controls the online pulse jet cleaning system to start, and uses 0.4MPa to 0.5MPa compressed air to perform reverse jet cleaning on the high-temperature metal filter bag, peeling off the dust particles on the surface of the filter bag and collecting them in the ash hopper below the filter element; The clean high-temperature flue gas after dust removal enters the SCR denitration reactor arranged on the upper part of the integrated box from bottom to top. The SCR denitration reactor is equipped with a multi-layered vanadium-titanium honeycomb SCR catalyst module; Before or during the flue gas entering the SCR denitration reactor, an ammonia-containing reducing agent is sprayed into the flue gas through an ammonia spray gun via an ammonia injection module arranged in the inlet flue of the SCR denitration reactor. The ammonia spray gun is connected to the ammonia supply pipeline through a control valve, and an opening command is issued by the intelligent control module to start on-demand injection; The catalyst characteristic identification module included in the intelligent control module performs online identification of the current reaction activity, blockage status and remaining life of the SCR catalyst. The identification process includes collecting data at least including flue gas composition, temperature and catalyst bed pressure drop at the inlet and outlet of the SCR reactor, and evaluating it in combination with a preset catalyst kinetic model or historical trend to dynamically modify the basic settings of the ammonia injection gun; The operating condition disturbance prediction module identifies the current operating conditions based on the operating condition model library formed by cluster analysis of industrial production equipment operating data, and predicts the disturbance trend of the SCR inlet flue gas parameters in the next 5 to 30 minutes; The collaborative optimization control module is based on a fuzzy logic or rule-based expert system. It performs a weighted fusion analysis on the output results of the catalyst characteristic identification module and the operating condition disturbance prediction module to generate the final control instructions for regulating the ammonia injection module. The flue gas treated by the denitrification reaction is discharged from the flue gas outlet at the top of the SCR denitrification reactor.

[0017] The present invention provides a high-efficiency dust and nitrate integrated SCR denitrification system and method in a high-temperature and low-dust environment. It has the following beneficial effects: 1. This invention integrates the high-temperature dust removal unit and the SCR denitrification reactor into a single housing, achieving a highly compact and integrated flue gas purification system. This innovative design not only significantly optimizes the equipment's footprint and reduces system construction complexity, but also effectively improves the overall efficiency of the synergistic removal of dust and nitrogen oxides from high-temperature flue gas, providing a highly efficient and intensive solution for achieving standard flue gas emissions in industrial production facilities.

[0018] 2. By placing a high-temperature dust removal unit upstream of the flue gas inlet of the SCR denitrification reactor, the present invention can effectively and preemptively remove large quantities of dust particles carried in the high-temperature flue gas. This pre-cleaning measure provides a clean flue gas environment for the vanadium-titanium honeycomb SCR catalyst used in the subsequent selective catalytic reduction reaction, significantly reducing the risk of catalyst activity loss due to factors such as dust abrasion, pore blockage, and alkali or heavy metal poisoning. This effectively extends the catalyst's service life and ensures the long-term, stable, and efficient operation of the SCR denitrification system.

[0019] 3. The present invention utilizes an intelligent control module, with its integrated catalyst property identification module, operating condition disturbance prediction module, and collaborative optimization control module working in precise coordination to dynamically adapt to the complex changes in the operating conditions of industrial production equipment and the natural evolution of the SCR catalyst's own reaction characteristics. This makes the ammonia injection module's ammonia injection operation more precise, timely, and intelligent, not only ensuring efficient nitrogen oxide removal, but also significantly reducing unnecessary ammonia slip and optimizing reducing agent consumption, thereby improving the economic and environmental friendliness of the entire denitrification process. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a system process flow chart of the present invention; Figure 2 It is a schematic diagram of the integrated box structure of the present invention.

[0021] Among them, 1. Integrated box; 2. High-temperature dust removal unit; 3. SCR denitrification reactor; 4. Ash hopper; 5. Flue gas inlet; 6. Flue gas outlet; 7. Filter element; 8. SCR catalyst module; 9. Online pulse jet cleaning system. DETAILED DESCRIPTION

[0022] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the present specification. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0023] Please see the attached Figure 1 -Attached Figure 2 The embodiment of the present invention provides a high-efficiency integrated SCR denitrification system for high-temperature and low-dust environments, including an integrated box, wherein the following are integrated in the integrated box: A high-temperature dust removal unit is used to remove dust from high-temperature flue gas from industrial production equipment that generates flue gas. The high-temperature dust removal unit is located at the lower part of the integrated box, and includes a flue gas inlet, an airflow distribution device, and a filter element with a gradient three-dimensional porous metal fiber structure, and an ash hopper located below the filter element. The filter element is used to collect dust removed by the filter element; an SCR denitrification reactor is used to carry out a denitrification reaction on the clean high-temperature flue gas after dust removal to control the nitrogen oxide emission concentration below a predetermined target value. The treated flue gas is discharged from its upper flue gas outlet. The SCR denitrification reactor is located at the upper part of the integrated box and downstream of the high-temperature dust removal unit, and includes a multi-layered SCR catalyst module; a vanadium-titanium honeycomb SCR catalyst is arranged in the SCR catalyst module; an ammonia injection module is used The ammonia-containing reducing agent is injected into the flue gas upstream or inside the SCR denitrification reactor through a spray gun; an intelligent control module is used to control the ammonia injection operation of the ammonia injection module and the ash cleaning operation of the high-temperature dust removal unit, and the intelligent control module includes: a catalyst characteristic identification module, which identifies the reaction characteristics of the SCR catalyst online, and determines the basic settings for controlling ammonia injection based on this; an operating condition disturbance prediction module, which identifies the operating condition mode of the industrial production equipment that generates flue gas, predicts the expected disturbance of the flue gas at the inlet of the SCR denitrification reactor, and determines the forward-looking compensation information for adjusting ammonia injection based on this; a collaborative optimization control module, which is configured to evaluate the output of the catalyst characteristic identification module and the output of the operating condition disturbance prediction module, and determine the final ammonia injection control instruction through adaptive weight fusion and multi-objective collaborative decision-making.

[0024] The airflow distribution device is located downstream of the flue gas inlet of the high-temperature dust removal unit and upstream of the filter element. The airflow distribution device is used to make the flue gas flow velocity and flow rate entering the filter element uniform. The airflow distribution device is a porous plate.

[0025] The integrated box is arranged vertically, and the flue gas inlet of the high-temperature dust removal unit is located on the side outside the integrated box. The clean high-temperature flue gas after dust removal flows vertically upward from the high-temperature dust removal unit into the SCR denitrification reactor. The pressure resistance of the SCR denitrification reactor is ±8000Pa.

[0026] The filter element is a high-temperature metal filter bag, and the high-temperature dust removal unit also includes an online pulse jet cleaning system, which is used to remove dust attached to the high-temperature metal filter bag. The online pulse jet cleaning system uses compressed air of 0.4MPa to 0.5MPa for spraying. The intelligent control module starts the online pulse jet cleaning system when the pressure difference on both sides of the high-temperature metal filter bag is greater than -7kPa.

[0027] The SCR catalyst modules in the SCR denitration reactor have an interlayer spacing of 1.2 m, and the SCR catalyst modules are arranged in a 6×7 modular format. The SCR denitration reactor is housed in a shell made of 6 mm thick Q355B heat-resistant steel and provided with an external insulation layer with a total thickness of 300 mm. The insulation layer includes a 200 mm thick aluminum silicate needle-punched blanket and a 100 mm thick rock wool.

[0028] The operating condition disturbance prediction module identifies the operating condition mode of the industrial production equipment that generates flue gas by constructing a clustering algorithm of 5 to 15 typical operating condition mode libraries, and predicts the expected disturbance of the flue gas at the inlet of the SCR denitrification reactor in the next 5 to 30 minutes; the update cycle of the operating condition disturbance prediction module is 1 to 5 minutes.

[0029] The collaborative optimization control module uses fuzzy logic control or a rule-based expert system to perform multi-objective collaborative decision-making to determine the final ammonia injection control instruction; the update cycle of the collaborative optimization control module is 1 to 10 seconds.

[0030] For the high-temperature dust removal unit, in this embodiment, its core function is to perform preliminary and efficient purification treatment on the high-temperature flue gas generated from a specific industrial production process (such as cement manufacturing or steel smelting industries) to remove the solid particulate matter entrained therein.

[0031] The high-temperature dust removal unit occupies the lower area of ​​the overall integrated box structure. This layout is conducive to the natural flow of flue gas and the subsequent connection with the upper SCR denitrification reactor.

[0032] Specifically, the flue gas inlet of the high-temperature dust removal unit is located on the side of the integrated housing. This side-intake design, combined with the vertical layout of the housing, helps guide the high-temperature flue gas into the dust removal area in a specific manner, laying the foundation for subsequent airflow organization.

[0033] After the flue gas enters the high-temperature dust removal unit through the flue gas inlet and before it reaches the core filter component, the flue gas first flows through the airflow uniform distribution device. The airflow uniform distribution device is physically arranged downstream of the flue gas inlet and upstream of the filter element of the gradient three-dimensional porous metal fiber structure. Its key role is to effectively comb and adjust the introduced non-uniform flue gas flow, so as to make the velocity distribution and flow distribution of the flue gas entering the subsequent filter element tend to be uniform across the entire cross section. This uniformity is of great significance for ensuring that each filter element unit can bear the filtration load evenly, avoiding local overload or insufficient treatment, and extending the overall service life of the filter element. In a preferred embodiment, the airflow uniform distribution device can be implemented by a porous plate with a relatively simple structure and a definite effect.

[0034] The uniform high-temperature flue gas treated by the air flow distribution device then contacts the filter element with a gradient three-dimensional porous metal fiber structure. In the specific implementation of the present invention, this filter element is preferably in the form of a high-temperature metal filter bag. This filter bag is characterized by its unique gradient three-dimensional porous metal fiber structure, which can maintain structural stability and filtering performance under high-temperature working conditions. Its main responsibility is to physically intercept and separate dust particles entrained in the flue gas, so that the dust gradually accumulates on the surface of the filter bag. According to the description in the claims, this filter element also assumes the function of preliminary collection of dust removed from itself, which means that the surface of the filter bag is the place where dust particles are separated from the gas phase and temporarily stay.

[0035] To collect and remove dust that is intercepted by and subsequently removed from the filter element's surface, an ash hopper is installed beneath the filter element. This hopper serves as a collection container for dust that is removed and settled from the filter element (such as a high-temperature metal filter bag) during the cleaning process, and stores it for subsequent discharge from the system.

[0036] To ensure the continuous and effective operation of the gradient three-dimensional porous metal fiber filter elements (i.e., high-temperature metal filter bags) and prevent excessive dust accumulation leading to excessive filtration resistance or decreased filtration efficiency, the high-temperature dust removal unit is further equipped with an online pulse jet cleaning system. The core task of this cleaning system is to periodically or on-demand remove the dust layer adhering to the surface of the high-temperature metal filter bags. It operates by using compressed air in a reverse pulse jet. In one specific embodiment, the system uses compressed air with a pressure range of 0.4 MPa to 0.5 MPa as the cleaning medium. The initiation of the cleaning operation is controlled by the intelligent control module based on preset logic. Specifically, when the intelligent control module detects that the flue gas pressure differential across the high-temperature metal filter bags exceeds a set threshold, for example, greater than -7 kPa, the online pulse jet cleaning system is automatically triggered. The instantaneous high-pressure airflow impacts the filter bags, dislodging any adhering dust into the ash hopper below. In this way, through effective dust removal and timely cleaning, the high-temperature dust removal unit can provide clean high-temperature flue gas that meets the process requirements for the subsequent SCR denitrification reaction.

[0037] In this embodiment, the SCR denitrification reactor primarily processes clean, high-temperature flue gas from the upstream high-temperature dust removal unit. Through a catalytic reduction reaction, it converts nitrogen oxides (NOx) in the flue gas into nitrogen and water, ensuring that the NOx concentration in the flue gas ultimately discharged from the reactor's upper flue gas outlet meets the predetermined target value.

[0038] The SCR denitrification reactor is located in the upper part of the integrated housing, downstream of the flue gas flow from the high-temperature dust removal unit. This layout ensures that the flue gas entering the catalyst area has a low dust content, which helps protect the catalyst and maintain its long-term activity.

[0039] The reactor is equipped with multiple layers of SCR catalyst modules, which serve as core components for catalyst support and the gas-solid reaction interface. Each SCR catalyst module is filled with a vanadium-titanium honeycomb SCR catalyst. This vanadium-titanium catalyst is selected for its excellent NOx catalytic reduction activity and stability within a suitable temperature range (e.g., 280°C-420°C). The honeycomb structure provides a large surface area and low flue gas flow resistance.

[0040] To optimize flue gas distribution and facilitate maintenance, the SCR catalyst modules are preferably arranged in a modular format, for example, a 6×7 modular array. A specific spacing between the multiple catalyst modules, preferably 1.2 meters, is maintained. This design promotes uniform flue gas mixing and provides space for maintenance.

[0041] The SCR denitration reactor shell is preferably made of heat-resistant steel (such as 6mm thick Q355B steel plate) to withstand high temperatures and potentially corrosive environments. To maintain the required reaction temperature and reduce heat loss, the reactor shell is equipped with an insulation layer with a total thickness of preferably 300mm. This insulation layer can be composed of multiple layers, such as a 200mm thick inner layer of aluminum silicate needle-punched blanket and a 100mm thick outer layer of rock wool, which together ensure the reactor operates efficiently at an appropriate temperature.

[0042] In this embodiment, the core function of the ammonia injection module is to precisely dose the ammonia-containing reducing agent required for the chemical reaction into the flue gas being treated. This ammonia-containing reducing agent, such as ammonia water, ammonia gas produced by the hydrolysis of urea solution, or other suitable amino compounds, is the key reactant in the subsequent selective catalytic reduction reaction with nitrogen oxides (NOx) in the flue gas within the SCR denitrification reactor.

[0043] The ammonia injection module is responsible for evenly injecting a liquid or gaseous ammonia-containing reducing agent into the flue upstream of the SCR denitrification reactor in an atomized or dispersed form through a specially designed injection device—an ammonia lance. In certain process designs, it can also be directly injected into a specific area within the SCR denitrification reactor. The reductant injection point is chosen to be located in the flue upstream of the SCR denitrification reactor to ensure that the injected ammonia has sufficient time and space to fully mix with the high-temperature flue gas before entering the catalyst bed, forming an ammonia-flue gas mixture with a relatively uniform concentration distribution. This uniform mixing is a prerequisite for achieving an efficient and uniform denitrification reaction and minimizing ammonia slip (i.e., the discharge of unreacted ammonia with the flue gas).

[0044] The ammonia injection module, in its specific structural implementation, comprises at least one or more ammonia spray guns strategically placed within the inlet flue of the SCR denitrification reactor. These ammonia spray guns are designed to spray the ammonia-containing reducing agent in the form of fine droplets or a stream of air, increasing its contact area with the flue gas, thereby promoting its rapid evaporation (for liquid ammonia or aqueous ammonia) and mixing with the flue gas.

[0045] Each ammonia spray gun is connected via piping to one or more control valves for precisely regulating the flow of ammonia-containing reducing agent. These control valves are key actuators for on-demand reducing agent supply. Their degree of opening or closed state directly determines the amount of reducing agent injected into the flue gas per unit time.

[0046] More importantly, the operation of the control valve, and thus the entire ammonia injection module, does not operate in isolation but is precisely regulated by the intelligent control module. Using a complex algorithm, the intelligent control module calculates the optimal ammonia-nitrogen molar ratio (NH3 / NOx) required for current operating conditions based on a variety of factors, including the real-time NOx concentration, flue gas flow rate, and temperature at the SCR denitrification reactor inlet, as well as the current catalyst state as assessed by the catalyst property identification module. Based on this calculation, the intelligent control module generates corresponding control signals, instructing the control valve to adjust its opening degree or injection frequency, thereby achieving on-demand, dynamic, and precise injection of the ammonia-containing reducing agent. This intelligent closed-loop or open-loop control strategy with feedforward control is designed to minimize excessive reducing agent consumption, avoid secondary pollution (such as ammonium bisulfate formation or excessive ammonia slip), and optimize the overall operating economy of the system while meeting NOx emission standards.

[0047] In this embodiment, the intelligent control module's core mission is to provide precise, efficient, and adaptive automated control of key execution units within the system: the ammonia injection module's ammonia injection operation and the high-temperature dust removal unit's online pulse jet cleaning operation. This intelligent control module is not a single-function controller, but rather a complex system integrating a series of advanced algorithms and logic judgment units. Its purpose is to optimize overall denitrification efficiency, reduce operating costs, and ensure the long-term stability of the system.

[0048] Specifically, the intelligent control module mainly realizes its precise control function through the following three core sub-modules that cooperate with each other: The first is the Catalyst Characterization Module. This module is responsible for online diagnosis and assessment of the real-time "health status" of the vanadium-titanium honeycomb SCR catalyst, a core component within the SCR denitrification reactor. During long-term operation of an SCR denitrification system, the catalyst's reactivity gradually diminishes or changes due to factors such as chemical poisoning by trace harmful substances in the flue gas, physical wear, thermal aging, and pore blockage caused by soot. To address this inevitable performance evolution, the Catalyst Characterization Module continuously collects and analyzes key process parameters from the inlet and outlet sections of the SCR denitrification reactor. These parameters preferably include at least flue gas composition (such as NOx concentration, O2 concentration, and NH3 concentration), flue gas temperature, and catalyst bed pressure drop data. Combined with a pre-built and stored catalyst kinetics mathematical model or a trend analysis model based on extensive historical operating data, this module can periodically and quantitatively assess the current actual activity level of the vanadium-titanium honeycomb SCR catalyst, its potential level of blockage, and its estimated remaining service life. Based on this identification result, the module will dynamically correct and output the basic control setting parameters used to guide the ammonia injection module to perform ammonia injection, such as adjusting the baseline ammonia-nitrogen molar ratio (NH3 / NOx) or correcting the catalyst reaction rate constant, so as to ensure that the amount of ammonia injected can match the real-time catalytic capacity of the catalyst.

[0049] The second component is the operating condition disturbance prediction module. The operating load and process parameters of industrial production equipment (such as cement kilns and sintering machines) are often not constant. These fluctuations can directly lead to significant disturbances in key inlet parameters such as flue gas volume, flue gas temperature, and initial NOx concentration entering the SCR denitrification system. Relying solely on traditional feedback control often results in delayed system response and difficulty adapting to rapid or drastic operating condition changes. To address this issue, the present invention introduces an operating condition disturbance prediction module. This module uses advanced pattern recognition techniques, such as clustering algorithms, to learn and summarize various typical operating conditions exhibited by the flue gas-generating industrial production equipment during historical operation, thereby constructing a feature library containing, for example, 5 to 15 typical operating condition patterns. During actual system operation, this module can identify the current operating mode of the industrial production equipment in real time. Based on this mode and analysis of operating condition transition trends, it further predicts the expected disturbance amplitude and occurrence time of flue gas parameters (such as peak NOx concentration and flow rate fluctuations) at the inlet of the SCR denitrification reactor over a period of time in the future (e.g., preferably within the next 5 to 30 minutes). This module outputs its predictions as forward-looking compensation information, which is used to proactively adjust the ammonia injection strategy to address upcoming disturbances. To ensure timely and accurate predictions, the internal calculation and data update cycle of the operating disturbance prediction module is preferably set to 1 to 5 minutes.

[0050] The third module is the collaborative optimization control module. This module is the core of intelligent control decision-making, integrating and weighing the outputs from the catalyst characteristic identification module (reflecting the system's current internal capabilities) and the operating disturbance prediction module (reflecting upcoming external challenges facing the system). Because these two sources of information may, at certain moments, suggest different or even conflicting requirements for ammonia injection (for example, decreased catalyst activity requires increased ammonia injection, while a predicted load decrease suggests reduced injection), the collaborative optimization control module must employ advanced decision-making algorithms to find the global optimum. This module preferably employs artificial intelligence technologies, such as fuzzy logic control systems or rule-based expert systems, to comprehensively evaluate the two input signals. Through an adaptive weight fusion mechanism (dynamically adjusting the influence of the two signals in the final decision based on current operating conditions and control objectives) and multi-objective collaborative decision-making logic (for example, minimizing ammonia slip and minimizing operating energy consumption while ensuring outlet NOx compliance), it ultimately calculates and outputs a precise, dynamically optimized final ammonia injection control command. This command is directly transmitted to the ammonia injection module's actuators (such as the control valve) to achieve real-time, precise control of ammonia injection. To ensure rapid control response, the control instruction update period of the collaborative optimization control module is preferably set to 1 to 10 seconds.

[0051] In addition to providing complex control over ammonia injection, the intelligent control module also monitors the pressure differential across the high-temperature metal filter bags in the high-temperature dust removal unit. If this pressure differential exceeds a preset safety threshold (e.g., greater than -7 kPa, indicating excessive dust accumulation on the bag surface, impacting ventilation), the intelligent control module promptly activates the online pulse jet cleaning system, instructing it to perform a cleaning operation to restore the bag's filtration performance.

[0052] In summary, the intelligent control module of the present invention realizes advanced model-based, prediction-based, adaptive and multi-objective optimization control of the denitrification process through the collaborative work of its internal precision sub-modules, significantly improving the operating efficiency, stability and economy of the entire denitrification system.

[0053] Please see the attached Figure 1 -Attached Figure 2 The present invention also provides a high-efficiency dust and nitrate integrated SCR denitrification method under a high-temperature and low-dust environment, comprising the following steps: High-temperature flue gas from industrial production equipment is introduced into the integrated box and subjected to primary dust removal treatment by the high-temperature dust removal unit at the bottom of the integrated box; The high-temperature flue gas first passes through an air flow distribution device located downstream of the flue gas inlet and upstream of the filter element to uniformly distribute the flow velocity and flow rate; The flue gas after the airflow is evenly distributed enters the filter element with a gradient three-dimensional porous metal fiber structure arranged in the high-temperature dust removal unit to intercept high-temperature particulate matter. The filter element is preferably a high-temperature metal filter bag; When the pressure difference on both sides of the high-temperature metal filter bag exceeds the preset threshold, the intelligent control module controls the online pulse jet cleaning system to start, and uses 0.4MPa to 0.5MPa compressed air to perform reverse jet cleaning on the high-temperature metal filter bag, peeling off the dust particles on the surface of the filter bag and collecting them in the ash hopper below the filter element; The clean high-temperature flue gas after dust removal enters the SCR denitration reactor arranged on the upper part of the integrated box from bottom to top. The SCR denitration reactor is equipped with a multi-layered vanadium-titanium honeycomb SCR catalyst module; Before or during the flue gas entering the SCR denitration reactor, an ammonia-containing reducing agent is sprayed into the flue gas through an ammonia spray gun via an ammonia injection module arranged in the inlet flue of the SCR denitration reactor. The ammonia spray gun is connected to the ammonia supply pipeline through a control valve, and an opening command is issued by the intelligent control module to start on-demand injection; The catalyst characteristic identification module included in the intelligent control module performs online identification of the current reaction activity, blockage status and remaining life of the SCR catalyst. The identification process includes collecting data at least including flue gas composition, temperature and catalyst bed pressure drop at the inlet and outlet of the SCR reactor, and evaluating it in combination with a preset catalyst kinetic model or historical trend to dynamically modify the basic settings of the ammonia injection gun; The operating condition disturbance prediction module identifies the current operating conditions based on the operating condition model library formed by cluster analysis of industrial production equipment operating data, and predicts the disturbance trend of the SCR inlet flue gas parameters in the next 5 to 30 minutes; The collaborative optimization control module is based on a fuzzy logic or rule-based expert system. It performs a weighted fusion analysis on the output results of the catalyst characteristic identification module and the operating condition disturbance prediction module to generate the final control instructions for regulating the ammonia injection module. The flue gas treated by the denitrification reaction is discharged from the flue gas outlet at the top of the SCR denitrification reactor.

[0054] The method of this embodiment can be used to execute the above system embodiment. Its principles and technical effects are similar and will not be described in detail here.

[0055] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. High-efficiency dust and nitrate integrated SCR denitrification system in high temperature and low dust environment, characterized by: It includes an integrated box, wherein the integrated box integrates the following: a high-temperature dust removal unit for removing dust from high-temperature flue gas from an industrial production device that generates flue gas, the high-temperature dust removal unit being located at the lower portion of the integrated housing and comprising a flue gas inlet, an airflow distribution device, and a filter element having a gradient three-dimensional porous metal fiber structure, and an ash hopper located below the filter element, the filter element being used to collect dust removed by the filter element; An SCR denitration reactor is used to perform a denitration reaction on the clean, high-temperature flue gas after dust removal to control the nitrogen oxide emission concentration below a predetermined target value. The treated flue gas is discharged from the upper flue gas outlet. The SCR denitration reactor is located at the upper part of the integrated housing and downstream of the high-temperature dust removal unit, and includes a multi-layered SCR catalyst module; a vanadium-titanium honeycomb SCR catalyst is installed in the SCR catalyst module; an ammonia injection module, for injecting an ammonia-containing reducing agent into the flue gas upstream of or inside the SCR denitration reactor through a spray gun; An intelligent control module is used to control the ammonia injection operation of the ammonia injection module and the dust cleaning operation of the high-temperature dust removal unit. The intelligent control module includes: a catalyst characteristic identification module for online identification of the reaction characteristics of the SCR catalyst and determining basic settings for controlling ammonia injection based on the characteristics; an operating condition disturbance prediction module for identifying an operating condition mode of the industrial production device generating flue gas, predicting an expected disturbance of the flue gas at the inlet of the SCR denitrification reactor, and determining forward-looking compensation information for adjusting ammonia injection based on the disturbance; The collaborative optimization control module is configured to evaluate the output of the catalyst characteristic identification module and the output of the operating condition disturbance prediction module, and determine the final ammonia injection control instruction through adaptive weight fusion and multi-objective collaborative decision-making.

2. The high-efficiency dust and nitrate integrated SCR denitration system in a high-temperature and low-dust environment according to claim 1 is characterized in that: The airflow distribution device is located downstream of the flue gas inlet of the high-temperature dust removal unit and upstream of the filter element. The airflow distribution device is used to make the flue gas flow velocity and flow rate entering the filter element uniform. The airflow distribution device is a porous plate.

3. The high-efficiency integrated SCR denitrification system for dust and nitrate in a high-temperature and low-dust environment according to claim 1 is characterized in that: The integrated box is arranged vertically, and the flue gas inlet of the high-temperature dust removal unit is located on the side outside the integrated box. The clean high-temperature flue gas after dust removal flows vertically upward from the high-temperature dust removal unit into the SCR denitrification reactor. The pressure resistance of the SCR denitrification reactor is ±8000Pa.

4. The high-efficiency dust and nitrate integrated SCR denitration system in a high-temperature and low-dust environment according to claim 1 is characterized in that: The filter element is a high-temperature metal filter bag, and the high-temperature dust removal unit also includes an online pulse jet cleaning system, which is used to remove dust attached to the high-temperature metal filter bag. The online pulse jet cleaning system uses compressed air of 0.4MPa to 0.5MPa for spraying. The intelligent control module starts the online pulse jet cleaning system when the pressure difference on both sides of the high-temperature metal filter bag is greater than -7kPa.

5. The high-efficiency dust and nitrate integrated SCR denitration system in a high-temperature and low-dust environment according to claim 1 is characterized in that: The SCR catalyst modules in the SCR denitration reactor have an interlayer spacing of 1.2 m, and the SCR catalyst modules are arranged in a 6×7 modular format. The SCR denitration reactor is housed in a shell made of 6 mm thick Q355B heat-resistant steel and provided with an external insulation layer with a total thickness of 300 mm. The insulation layer includes a 200 mm thick aluminum silicate needle-punched blanket and a 100 mm thick rock wool.

6. The high-efficiency dust and nitrate integrated SCR denitration system in a high-temperature and low-dust environment according to claim 1 is characterized in that: The ammonia injection module includes at least one ammonia spray gun arranged in the inlet flue of the SCR denitration reactor. The ammonia spray gun is connected to a control valve for adjusting the flow of the ammonia-containing reducing agent, and the ammonia-containing reducing agent injection is started by the instruction of the intelligent control module.

7. The high-efficiency integrated SCR denitrification system for dust and nitrate in a high-temperature and low-dust environment according to claim 1 is characterized in that: The catalyst characteristic identification module collects and analyzes data at the inlet and outlet of the SCR denitrification reactor online, including at least flue gas composition, temperature, and catalyst bed pressure drop, and combines it with a preset catalyst kinetic model or historical data trend to periodically evaluate the current activity level, blockage degree, or expected remaining life of the vanadium-titanium honeycomb SCR catalyst to dynamically correct the basic settings of the ammonia spray gun.

8. The high-efficiency dust and nitrate integrated SCR denitration system in a high-temperature and low-dust environment according to claim 1 is characterized in that: The operating condition disturbance prediction module identifies the operating condition mode of the industrial production equipment that generates flue gas by constructing a clustering algorithm of 5 to 15 typical operating condition mode libraries, and predicts the expected disturbance of the flue gas at the inlet of the SCR denitrification reactor in the next 5 to 30 minutes; the update cycle of the operating condition disturbance prediction module is 1 to 5 minutes.

9. The high-efficiency dust and nitrate integrated SCR denitration system in a high-temperature and low-dust environment according to claim 1 is characterized in that: The collaborative optimization control module uses fuzzy logic control or a rule-based expert system to perform multi-objective collaborative decision-making to determine the final ammonia injection control instruction; the update cycle of the collaborative optimization control module is 1 to 10 seconds.

10. A high-efficiency integrated SCR denitrification method for dust and nitrate in a high-temperature, low-dust environment, applied to a high-efficiency integrated SCR denitrification system for dust and nitrate in a high-temperature, low-dust environment as claimed in any one of claims 1 to 9, characterized in that: The following steps are involved: High-temperature flue gas from industrial production equipment is introduced into the integrated box and subjected to primary dust removal treatment by the high-temperature dust removal unit at the bottom of the integrated box; The high-temperature flue gas first passes through an air flow distribution device located downstream of the flue gas inlet and upstream of the filter element to uniformly distribute the flow velocity and flow rate; The flue gas after the airflow is evenly distributed enters the filter element with a gradient three-dimensional porous metal fiber structure arranged in the high-temperature dust removal unit to intercept high-temperature particulate matter. The filter element is preferably a high-temperature metal filter bag; When the pressure difference on both sides of the high-temperature metal filter bag exceeds the preset threshold, the intelligent control module controls the online pulse jet cleaning system to start, and uses 0.4MPa to 0.5MPa compressed air to perform reverse jet cleaning on the high-temperature metal filter bag, peeling off the dust particles on the surface of the filter bag and collecting them in the ash hopper below the filter element; The clean high-temperature flue gas after dust removal enters the SCR denitration reactor arranged on the upper part of the integrated box from bottom to top. The SCR denitration reactor is equipped with a multi-layered vanadium-titanium honeycomb SCR catalyst module; Before or during the flue gas entering the SCR denitration reactor, an ammonia-containing reducing agent is sprayed into the flue gas through an ammonia spray gun via an ammonia injection module arranged in the inlet flue of the SCR denitration reactor. The ammonia spray gun is connected to the ammonia supply pipeline through a control valve, and an opening command is issued by the intelligent control module to start on-demand injection; The catalyst characteristic identification module included in the intelligent control module performs online identification of the current reaction activity, blockage status and remaining life of the SCR catalyst. The identification process includes collecting data at least including flue gas composition, temperature and catalyst bed pressure drop at the inlet and outlet of the SCR reactor, and evaluating it in combination with a preset catalyst kinetic model or historical trend to dynamically modify the basic settings of the ammonia injection gun; The operating condition disturbance prediction module identifies the current operating conditions based on the operating condition model library formed by cluster analysis of industrial production equipment operating data, and predicts the disturbance trend of the SCR inlet flue gas parameters in the next 5 to 30 minutes; The collaborative optimization control module is based on a fuzzy logic or rule-based expert system. It performs a weighted fusion analysis on the output results of the catalyst characteristic identification module and the operating condition disturbance prediction module to generate the final control instructions for regulating the ammonia injection module. The flue gas treated by the denitrification reaction is discharged from the flue gas outlet at the top of the SCR denitrification reactor.

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