A flue gas multi-pollutant co-processing system

Abstract

The application discloses a flue gas multi-pollutant co-processing system, and belongs to the technical field of flue gas purification, to solve the technical problem of short service life of a catalytic filter bag for treating flue gas and high requirement on flue gas. In the processing system, a catalytic filter bag is built in an integrated dust remover; an oxidant conveying module for conveying an oxidant into a dry method reactor, a deacidifying agent conveying module for conveying a deacidifying agent into the dry method reactor and an activated carbon conveying module for conveying activated carbon into the dry method reactor are communicated with a flue gas inlet section of the dry method reactor; and a reducing agent conveying module for conveying a reducing agent into the integrated dust remover is communicated with a flue gas outlet section of the dry method reactor. Compared with the prior art, the application can shorten a process flow, reduce equipment floor area, reduce power consumption and material consumption (economy), ensure ultra-low emission of pollutants (environmental protection), has low transformation cost, long service life of the catalytic filter bag, simple operation and maintenance and high energy utilization rate.

Description

Technical Field

[0001] This application relates to the field of flue gas purification technology, and in particular to a multi-pollutant synergistic treatment system for flue gas. Background Technology

[0002] With increasingly stringent pollution control requirements, emission standards for municipal solid waste incineration flue gas are becoming more and more stringent. For example, some standards require NO... x Hourly average <80 mg / Nm 3 HCl < 10 mg / Nm 3 SO2 < 30 mg / Nm 3 To meet increasingly stringent pollution control requirements, existing flue gas purification processes need to incorporate SCR and wet scrubbing towers, forming a long-chain, segmented process of "SNCR + semi-dry + dry + activated carbon + bag filter + SCR denitrification + wet deacidification." However, this process suffers from drawbacks such as system complexity, high cost, large footprint, high power consumption, and wastewater generation. Furthermore, space constraints make it difficult to adapt to the retrofitting needs of existing facilities, hindering the technological upgrading of older plants.

[0003] To save floor space and reduce operating and equipment investment costs, the industry has begun to explore a new flue gas treatment technology centered on catalytic filter bags. Catalytic filter bags are used to filter catalysts (such as V₂O₅, WO₃, MnO₂). x Loading materials such as PTFE and PPS fibers onto traditional filter bags creates a system that can efficiently and synergistically remove particulate matter and gaseous pollutants (such as NO). x This technology utilizes a multifunctional composite material containing dioxins and other harmful substances. It can directly replace traditional dust collector filter bags, completing the technological upgrade within the existing equipment framework without requiring additional floor space or large-scale equipment investment.

[0004] Catalytic filter bags are suitable for flue gas environments of 160-260 ℃. When the flue gas temperature is below 200 ℃, a flue gas heating device (SGH or GGH) needs to be added between the SDA and the dust collector flue to heat the flue gas temperature to above 200 ℃ to meet the operating temperature requirements of the catalytic filter bags. However, this heating solution not only increases equipment investment and operating energy consumption, but also makes the heater susceptible to erosion and wear from high-dust flue gas, resulting in high maintenance costs. Furthermore, when the flue gas temperature is below 200 ℃, due to the limitations of catalyst characteristics, SO2 must be strictly controlled to ≤10 mg / Nm³. 3 The humidity must be below 22%; otherwise, it will cause blockage of the ammonium sulfate catalyst ((NH4)HSO4) and loss of active sites, significantly reducing denitrification efficiency and filter bag lifespan. Furthermore, injecting activated carbon at temperatures above 200°C poses a risk of smoldering combustion, creating a safety hazard.

[0005] Currently, the flue gas from incineration undergoes a two-stage desulfurization process using "SDA + dry method." Because the SDA process employs slaked lime slurry spraying for desulfurization, the flue gas humidity increases by 2-5%, and due to limitations in the activity of the slaked lime, the SO2 concentration is difficult to consistently remain below 10 mg / Nm³. 3 Existing processes are insufficient to meet the stringent requirements of catalytic filter bag applications.

[0006] Therefore, providing a highly efficient synergistic treatment system for multiple pollutants in flue gas is a technical problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0007] This application discloses a multi-pollutant synergistic treatment system and method for flue gas, in order to solve the technical problems of short service life and high requirements for flue gas in related technologies.

[0008] To solve the above problems, this application adopts the following technical solution: In a first aspect, this application provides a multi-pollutant synergistic treatment system for flue gas, the system comprising a waste heat boiler, a dry reactor, a flue gas waste heat utilization module, an integrated dust collector, and a chimney connected sequentially along the flue gas flow direction.

[0009] Specifically, the integrated dust collector has a built-in catalytic filter bag; the flue gas inlet section of the dry reactor is connected to an oxidant delivery module for supplying oxidant to the dry reactor, a deacidifying agent delivery module for supplying deacidifying agent to the dry reactor, and an activated carbon delivery module for supplying activated carbon to the dry reactor; the flue gas outlet section of the dry reactor is connected to a reducing agent delivery module for supplying reducing agent to the integrated dust collector.

[0010] Furthermore, the flue gas waste heat utilization module outlet is equipped with a main flue and a bypass flue. The bypass flue is equipped with a fixed adsorption module, which is used to adsorb the regeneration tail gas during the regeneration of the catalytic filter bag. The desorbed gas outlet of the fixed adsorption module is connected to the chimney. The outlet of the flue gas waste heat recovery module is connected to the chimney and / or the fixed adsorption module; The inlet of the bypass flue is located on the main flue downstream of the outlet of the flue gas waste heat utilization module. Furthermore, the fixed adsorption module includes a first isolation valve located in the main flue, a second isolation valve located in the bypass flue, and a first control valve connected to the fixed adsorption bed for discharging desorbed gas. The first control valve is also connected to the inlet of the dry reactor.

[0011] Furthermore, the integrated dust collector outlet is also equipped with a hot flue gas duct, which is connected to a heat recovery device to recover heat from the flue gas.

[0012] Furthermore, the oxidant delivery module includes an ozone generator and a hydrogen peroxide evaporation system; The ozone generation system includes an oxygen tank for storing and supplying oxygen, a compressed air inlet pipeline for serving as a backup oxygen source, the oxygen tank and the compressed air inlet pipeline are connected to the ozone generator, and the ozone generator is connected to a cooling water system. The hydrogen peroxide evaporation system includes a hydrogen peroxide raw water tank for storing hydrogen peroxide, a hydrogen peroxide heater for heating the hydrogen peroxide in the hydrogen peroxide raw water tank, and a hydrogen peroxide buffer tank for storing gaseous hydrogen peroxide. The outlet of the ozone generator is connected to the outlet of the hydrogen peroxide buffer tank, which is then connected to the inlet of the mixer. The mixer is used to fully mix gaseous ozone and gaseous hydrogen peroxide in a certain proportion before sending them into the dry reactor.

[0013] Furthermore, the hot flue is connected to the hydrogen peroxide heater.

[0014] Furthermore, the reducing agent delivery module includes a storage tank for storing liquid ammonia or ammonia water, an ammonia water evaporator for evaporating ammonia water to generate ammonia gas, an ammonia gas buffer tank for storing gaseous ammonia, and an ammonia gas mixer for mixing ammonia gas with air and diluting it to a safe concentration before sending the mixed gas into the integrated dust collector.

[0015] Furthermore, the hot flue channel is connected to the ammonia evaporator.

[0016] Furthermore, the deacidifying agent conveying module includes a deacidifying agent storage silo for storing the deacidifying agent, a coarse powder quantitative conveying device for quantitatively conveying the coarse deacidifying agent, a fine powder grinding mill for grinding the coarse deacidifying agent into fine powder, a deacidifying agent fine powder silo for storing the deacidifying agent fine powder, and a fine powder quantitative conveying device for quantitatively conveying the fine deacidifying agent to the dry reactor.

[0017] Furthermore, the activated carbon conveying module includes an activated carbon raw material storage bin for storing activated carbon and an activated carbon metering conveying device for metering activated carbon into the dry reactor.

[0018] The technical solution adopted in this application can achieve the following beneficial effects: By concentrating the addition of deacidifying agents, adsorbents, and reducing agents in a dry reactor and an integrated dust collector, a short-path flue gas purification process is formed by integrating dry deacidification, catalytic filtration, and regeneration technologies. This achieves highly efficient synergistic removal of nitrogen oxides, sulfur oxides, hydrogen chloride, heavy metals, and dioxins, reducing redundant equipment configuration and flue gas resistance, thus making the process compact and significantly reducing equipment investment, floor space costs, and operating costs. It achieves synergistic and efficient removal of multiple pollutants while simultaneously meeting ultra-low emission standards. By periodically adding oxidants or when the concentration of nitrogen oxides in the flue gas is too high, the catalytic filter bags can be periodically regenerated or their catalytic efficiency for nitrogen oxides can be improved, restoring the catalytic activity and filtration performance of the filter bags, reducing their replacement frequency, and simultaneously improving flue gas pollutant emission indicators, thus balancing economic and environmental performance. By adding an adsorption fixed bed and its regeneration device, dioxin removal can be achieved during the regeneration of catalytic filter bags, reducing environmental risks, extending the service life of the adsorbent, and reducing operating costs. By employing a high-efficiency dry reactor to completely replace the traditional "SDA (slaked lime slurry) + dry process (slaked lime / baking soda)" deacidification method, the deacidification efficiency is significantly improved by utilizing highly active deacidifying agents (baking soda, high-specific-ratio slaked lime), optimizing the deacidification reaction temperature, and increasing the gas-solid contact time. This meets the requirement of catalytic filter bags for inlet SO2 concentrations <10 mg / Nm³. 3 The high requirements were met, while the utilization rate of the deacidifying agent was improved, and the fly ash production was reduced. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of the flue gas multi-pollutant synergistic treatment system provided in Example 1; Figure 2 This is a schematic diagram of the deacidifying agent delivery module in the flue gas multi-pollutant synergistic treatment system provided in Example 1; Figure 3 This is a schematic diagram of the activated carbon conveying module in the flue gas multi-pollutant synergistic treatment system provided in Example 1; Figure 4 This is a schematic diagram of the oxidant delivery module in the flue gas multi-pollutant synergistic treatment system provided in Example 1; Figure 5 This is a schematic diagram of the reducing agent delivery module in the flue gas multi-pollutant synergistic treatment system provided in Example 1; Figure 6 This is a schematic diagram of the fixed adsorption module in the flue gas multi-pollutant synergistic treatment system provided in Example 1.

[0021] The attached figures are labeled as follows: 100. Waste heat boiler; 200. Dry reactor; 300. Integrated dust collector; 310. Main flue; 320. Bypass flue; 330. Hot flue; 410. Exhaust fan; 420. Flue gas waste heat recovery module; 500. Chimney; 610. Deacidifying agent conveying module; 611. Deacidifying agent storage silo; 612. Coarse powder quantitative conveying device; 613. Fine powder grinding mill; 614. Deacidifying agent fine powder silo; 615. First induced draft fan; 616. Fine powder quantitative conveying device; 617. First blower; 620. Activated carbon conveying module; 621. Activated carbon raw material storage silo; 622. Activated carbon quantitative conveying device; 623. Second blower; 700. Oxidant delivery module; 701. Oxygen tank; 702. Compressed air inlet pipeline; 703. First pressure reducing valve; 704. Cooling water system; 705. Ozone generator; 706. Second pressure reducing valve; 707. First flow meter; 708. Hydrogen peroxide raw water tank; 709. Hydrogen peroxide heater; 710. Hydrogen peroxide buffer tank; 711. Third pressure reducing valve; 712. Second flow meter; 713. Third fan; 714. Mixer; 715. Fourth pressure reducing valve; 716. Second control valve; 717. Fifth flow meter; 800. Reducing agent delivery module; 801. Ammonia storage tank; 802. Ammonia evaporator; 803. Ammonia buffer tank; 804. Ammonia mixer; 805. Dilution fan; 806. Third flow meter; 807. Third control valve; 808. Sixth flow meter; 900. Fixed adsorption module; 901. First isolation valve; 902. Second isolation valve; 903. Fixed adsorption bed; 904. First control valve; 905. Fourth flow meter; 906. Heater; 907. Fourth control valve. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be described in detail below. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0023] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0024] Catalytic filter bags are suitable for flue gas environments of 160-260 ℃. When the flue gas temperature is below 200 ℃, a flue gas heating device (SGH or GGH) needs to be added between the SDA and the dust collector flue to heat the flue gas temperature to above 200 ℃ to meet the operating temperature requirements of the catalytic filter bags. However, this heating solution not only increases equipment investment and operating energy consumption, but also makes the heater susceptible to erosion and wear from high-dust flue gas, resulting in high maintenance costs. Furthermore, when the flue gas temperature is below 200 ℃, due to the limitations of catalyst characteristics, SO2 must be strictly controlled to ≤10 mg / Nm³. 3 The humidity must be less than 22%; otherwise, it will cause blockage of the ammonium sulfate catalyst ((NH4)HSO4) and loss of active sites, significantly reducing denitrification efficiency and filter bag lifespan. Furthermore, injecting activated carbon at temperatures above 200°C poses a risk of smoldering combustion, creating a safety hazard. Existing processes cannot meet the stringent requirements for catalytic filter bag applications.

[0025] This application improves the acid removal efficiency through a dry reactor, ensuring that the SO2 concentration in the flue gas at the inlet of the integrated dust collector remains consistently below 10 mg / Nm³. 3 By periodically adding oxidant or when the concentration of nitrogen oxides in the flue gas is too high, the catalytic filter bag can be regenerated or its catalytic efficiency for nitrogen oxides can be improved, restoring the catalytic activity and filtration performance of the filter bag, reducing its replacement frequency, and simultaneously improving the emission indicators of flue gas pollutants.

[0026] The following is in conjunction with the appendix Figures 1 to 6 This application provides a detailed description of a multi-pollutant synergistic treatment system, treatment method, and application for flue gas through specific embodiments and application scenarios.

[0027] Reference Figures 1-6In one aspect, this application provides a multi-pollutant synergistic treatment system for flue gas. The system includes a waste heat boiler 100, a dry reactor 200, an integrated dust collector 300, and a chimney 500 connected sequentially along the flue gas flow direction. Exemplarily, during operation, high-temperature flue gas first enters the waste heat boiler 100. While recovering waste heat, the flue gas temperature can be initially reduced, creating suitable temperature conditions for subsequent acid removal and dust removal. Subsequently, the flue gas enters the dry reactor 200, where a dry acid removal agent (such as quicklime or sodium bicarbonate) is injected and reacts with acidic gases (such as SO2, HCl, etc.) in the flue gas in the following reactions (1)-(5), where (1)-(3) are reactions that occur when the acid removal agent is sodium bicarbonate, and (4)-(5) are reactions that occur when the acid removal agent is quicklime, achieving efficient removal of acidic pollutants. The flue gas after acid removal treatment, carrying some reaction products and original particulate matter, enters the integrated dust collector 300. This dust collector integrates filtration and secondary reaction functions. It not only removes dust and deacidification byproducts from flue gas through the outer membrane of the catalytic filter bag, but its filter layer surface can also continue to react with incompletely reacted acidic gases, further improving removal efficiency. This treatment system can handle multiple pollutants (particulate matter, SO2 ... x The flue gas undergoes synergistic purification with HCl and other chemicals; the purified flue gas is then discharged into the atmosphere through a 500-meter chimney.

[0028] 2NaHCO3(s)→Na2CO3(s)+H2O(g)+CO2(g)--(1) Na2CO3(s)+2HCl(g)→2NaCl(s)+H2O(g)+CO2(g)--(2) Na2CO3(s)+SO2(g)+1 / 2O2(g)→Na2SO4(s)+CO2(g)--(3) Ca(OH)2(s)+2HCl(g)→CaCl2(s)+2H2O(g)--(4) Ca(OH)2(s)+SO2(g)+1 / 2O2(g)→CaSO4(s)+H2O(g)--(5) Specifically, the integrated dust collector 300 has a built-in catalytic filter bag, an internal filtration velocity of 0.6-0.8 m / min, and an inlet-outlet pressure difference of 1000-1500 Pa. For example, ... Figure 1As shown, this catalytic filter bag is a composite filter material that integrates particulate filtration and catalytic reaction functions. Its base material is a high-temperature and corrosion-resistant fiber filter material (such as polyphenylene sulfide (PPS), polytetrafluoroethylene (PTFE), or glass fiber), and catalytically active components are loaded on the surface or inside the filter material. This catalytic filter bag achieves efficient dust collection and further removal of acidic gases, heavy metals, and dioxins. Simultaneously, a catalytic reducing agent (such as ammonia or urea pyrolysis product NH3) reacts with nitrogen oxides (NOx) in the flue gas. x The reaction produces harmless nitrogen (N2) and water (H2O), achieving integrated and synergistic treatment of acid removal, denitrification and dust removal.

[0029] By adopting this technical solution, the integrated dust collector 300 achieves multi-functional integration of dust removal, denitrification, and deep purification of residual pollutants through built-in catalytic filter bags, which greatly simplifies the flue gas purification system process.

[0030] Specifically, the flue gas inlet section of the dry reactor 200 is connected to a deacidifying agent delivery module 610 for supplying deacidifying agent into the dry reactor 200 and an activated carbon delivery module 620 for supplying activated carbon into the dry reactor 200. The reaction temperature of the deacidifying agent and activated carbon in the dry reactor 200 is less than 200 ℃, and the residence time in the dry reactor 200 is 2s-4s. The excess coefficient of sodium bicarbonate is 1.05-1.2, and the excess coefficient of slaked lime is 1.5-2.0. For example, such as... Figure 1 As shown, during operation, the flue gas after waste heat recovery enters the dry reactor 200. At the flue gas inlet section of the dry reactor 200, the deacidifying agent delivery module 610 injects dry powder deacidifying agent (such as Ca(OH)2 or NaHCO3) into the reactor via compressed air or mechanical injection to remove acidic gases such as SO2 and HCl. The activated carbon delivery module 620 injects high-specific-surface-area activated carbon powder (or granules) into the dry reactor 200 via a pneumatic conveying system. The activated carbon is suspended in the flue gas, utilizing its rich microporous structure and surface functional groups to efficiently adsorb trace pollutants in the flue gas. Among these, dioxin-like pollutants (PCDD / Fs) are enriched on the surface of the activated carbon and carried to the downstream dust collector for interception; elemental mercury (Hg) and mercury oxide (Hg) are also adsorbed. 2+ Pollutants are fixed through physical adsorption and surface catalytic oxidation. After adsorbing pollutants, activated carbon enters the integrated dust collector 300 with the flue gas, forming a dust layer containing pollutants on the surface of the filter bags. This dust is ultimately trapped and discharged from the system with fly ash. The surface of Ca(OH)2 particles can catalyze the partial oxidation of Hg to Hg. 2+ This makes it easier for activated carbon to adsorb; and activated carbon can also serve as a micro-reaction platform for deacidification reactions, extending the reaction residence time and improving the overall purification efficiency.

[0031] By adopting this technical solution, the adsorbent and deacidifying agent are introduced into the dry reactor together, and the adsorption process and deacidification process are integrated into the dry reactor. This achieves the synergistic purification of acidic gases such as SO2 and HCl with pollutants such as mercury and dioxins, and simplifies the system process.

[0032] In some embodiments, the deacidifying agent conveying module 610 includes a deacidifying agent storage silo 611 for storing deacidifying agent, a coarse powder metering conveying device 612 for metering coarse deacidifying agent, a fine powder mill 613 for grinding the coarse deacidifying agent into fine powder, a deacidifying agent fine powder silo 614 for storing deacidifying agent fine powder, a fine powder metering conveying device 616 for metering fine deacidifying agent, a first induced draft fan 615 for transporting fine deacidifying agent from the deacidifying agent fine powder silo 614 to the fine powder metering conveying device 616, and a first blower 617 for conveying the metered fine deacidifying agent to the dry reactor 200. For example, as shown... Figure 1 and Figure 2 As shown, the deacidifying agent (such as NaHCO3 or Ca(OH)2) is first stored in the deacidifying agent storage silo 611, kept dry and moisture-proof to ensure material activity. When the system starts, the coarse powder quantitative conveying device 612 (such as a screw feeder or loss-in-weight feeder) precisely controls the discharge rate of the coarse powder deacidifying agent according to the concentration of acidic gas in the flue gas and the processing load, and continuously and stably conveys it to the fine powder grinding mill 613. In the fine powder grinding mill 613 (such as an air jet mill, ball mill, or impact mill), the coarse powder deacidifying agent is ground into fine powder with smaller particle size and larger specific surface area (baking soda, after grinding, has a particle size smaller than...). slaked lime has a specific surface area greater than 40 m² 2 / g), significantly improving its reaction rate and removal efficiency with acidic gases such as SO2 and HCl in flue gas. The ground fine powder enters the deacidifying agent fine powder silo 614 through pipeline for temporary storage. This silo is equipped with a level gauge, dust filter element and anti-bridging device (such as pneumatic vibrator or fluidizing plate) to prevent agglomeration and bridging, and ensure smooth material discharge. When fine powder needs to be sprayed, the first induced draft fan 615 (i.e., high negative pressure induced draft fan) is started, and the fine powder deacidifying agent is transported from the fine powder grinder 613 to the deacidifying agent fine powder silo 614 through high negative pressure material extraction, realizing a closed, dust-free and controllable intermediate transfer process. Subsequently, the first blower 617 (such as Roots blower or centrifugal blower) acts as a positive pressure conveying power source, injecting high-pressure clean air into the system, and pushing the metered fine powder deacidifying agent to the flue gas inlet section of the dry reactor 200 through the fine powder metering conveying device 616. Under the action of high-speed airflow, the fine powder of deacidifying agent diffuses fully in the flue and mixes violently with the high-temperature flue gas, resulting in a deacidification reaction and achieving efficient removal of acidic gases.

[0033] This technical solution employs multi-stage control of coarse powder metering, grinding, and fine powder metering to ensure that the particle size and dosage of the deacidifying agent meet the requirements for efficient reaction. The first induced draft fan 615 achieves closed material intake, preventing dust spillage. The first blower 617 provides stable thrust, ensuring long-distance, high-resistance conveying. The grinding fineness and injection volume can be flexibly adjusted to adapt to different flue gas conditions and emission standards. The silo buffer design prevents system interruption due to instantaneous demand fluctuations, ensuring continuous operation and achieving efficient, precise, and clean addition of the deacidifying agent, providing a reliable guarantee for dry deacidification reactions.

[0034] In some embodiments, the activated carbon conveying module 620 includes an activated carbon raw material storage bin 621 for storing activated carbon, an activated carbon metering conveying device 622 for metering activated carbon, and a second blower 623 for conveying the metered activated carbon to the dry reactor 200. For example, as shown... Figure 1 and Figure 3 As shown, highly adsorbent activated carbon powder (or granules) is pre-stored in the activated carbon raw material storage silo 621. This silo is a sealed structure, equipped with moisture-proof ventilation devices, a material level monitor, and anti-bridging devices (such as fluidizing plates or pneumatic vibrators) to prevent the activated carbon from absorbing moisture and clumping or bridging, ensuring smooth and stable feeding. When the system detects an increase in the concentration of trace pollutants such as mercury and dioxins in the flue gas, or when it enters a high-load operation phase, the control system initiates the activated carbon dosing program. The activated carbon quantitative conveying device 622 (such as a variable frequency screw feeder, loss-in-weight feeder, or rotary valve) precisely controls the output rate of the activated carbon according to the preset dosage or real-time feedback signal, achieving continuous, uniform, and adjustable quantitative supply. The quantitatively delivered activated carbon enters the conveying pipeline, where a second blower 623 (usually a Roots blower or a high-pressure centrifugal blower) provides high-pressure airflow, pneumatically conveying the activated carbon to the flue gas inlet section of the dry reactor 200. The airflow provided by the second fan 623 not only serves as the power source for transportation, but also promotes the rapid dispersion of activated carbon in the flue, forming a high-concentration suspended cloud that mixes thoroughly with the high-temperature flue gas, achieving efficient adsorption of pollutants in the flue gas.

[0035] Using this technical solution, the activated carbon delivery module 620 achieves rapid response and efficient capture of trace amounts of toxic pollutants.

[0036] Specifically, the flue gas inlet section of the dry reactor 200 is connected to an oxidant delivery module 700 for supplying oxidant into the dry reactor 200. For example, such as... Figure 1 and Figure 4 As shown, the oxidant delivery module 700 is used to inject oxidants such as ozone (O3) or hydrogen peroxide. The injection of oxidant is divided into two cases: one is to inject oxidant to regenerate the catalytic filter bag after the treatment system has been running for a period of time, and the other is to improve the catalytic efficiency of the catalytic filter bag for nitrogen oxides when the concentration of nitrogen oxides in the original flue gas is detected to be too high.

[0037] By adopting this technical solution, the catalytic activity and filtration performance of the catalytic filter bag can be restored through the oxidant delivery module 700, reducing its replacement frequency, and simultaneously improving its catalytic efficiency for nitrogen oxides, thereby improving the emission indicators of flue gas pollutants and balancing economic and environmental performance.

[0038] In some embodiments, the oxidant delivery module 700 includes an ozone generation system and a hydrogen peroxide evaporation system. The ozone generation system includes an oxygen tank 701 for storing and supplying oxygen, and a compressed air inlet pipe 702 for serving as a backup oxygen source. The compressed air inlet pipe 702 is connected to a high-voltage discharge ozone generator 705 via a first pressure reducing valve 703. The oxygen tank 701 is also connected to the inlet of the ozone generator 705. The ozone generator 705 is also provided with a cooling water inlet and outlet, and is connected to a cooling water system 704 via pipes. The hydrogen peroxide evaporation system is provided with a hydrogen peroxide raw water tank 708 for storing hydrogen peroxide. The hydrogen peroxide in the tank is heated by a hydrogen peroxide heater 709 and then enters a hydrogen peroxide buffer tank 710. The outlets of ozone generator 705 and hydrogen peroxide buffer tank 710 are connected to the inlet of mixer 714. Mixer 714 is used to fully mix gaseous ozone and gaseous hydrogen peroxide in a specific ratio. A second pressure-reducing valve 706 and a first flow meter 707 are respectively provided between the outlets of ozone generator 705 and hydrogen peroxide buffer tank 710 and the inlet of mixer 714 for reducing pressure and detecting flow of ozone gas, and a third pressure-reducing valve 711 and a second flow meter 712 for reducing pressure and detecting flow of hydrogen peroxide gas. Mixer 714 also includes a fourth pressure-reducing valve 715 for reducing pressure on the mixed gas and a third blower 713 for sending the mixed gas into dry reactor 200. For example, as shown... Figure 1 and Figure 4As shown, the oxidant delivery module 700 integrates an ozone generation system and a hydrogen peroxide evaporation system. It can independently or collaboratively deliver strong oxidizing gases to the dry reactor 200 to oxidize low-valence nitrogen oxides (such as NO) in the flue gas that are difficult to remove and dissolve in water into highly reactive high-valence nitrogen oxides (such as NO2), creating favorable conditions for efficient denitrification in the integrated dust collector 300. High-purity oxygen tank 701 is the preferred oxygen source to improve ozone yield and concentration. When oxygen supply is insufficient or the system is under maintenance, compressed air inlet pipe 702 can be switched as a backup gas source. Both gas sources are adjusted to suitable pressures by the first pressure reducing valve 703 before entering the high-voltage discharge ozone generator 705. Under the action of the high-voltage electric field, O2 molecules are decomposed and recombined to generate ozone (O3). The ozone generation process generates a large amount of heat. To prevent overheating and subsequent efficiency loss or damage, the ozone generator 705 is equipped with cooling water inlets and outlets, connected to an external cooling water system 704 (such as a closed-loop cooling tower or chiller unit) to maintain the temperature of the ozone generator 705 between 15-35 ℃, achieving continuous heat dissipation and ensuring stable operation. The hydrogen peroxide evaporation system uses a hydrogen peroxide raw water tank 708 to store a 20%-35% concentration hydrogen peroxide solution (H2O2). Liquid H2O2 is pumped into the hydrogen peroxide heater 709, where it rapidly evaporates and decomposes at high temperature, generating gaseous H2O2 and free radicals (·OH, ·HO2, etc.). The gas then enters the hydrogen peroxide buffer tank 710 for pressure stabilization and gas-liquid separation, ensuring stable output gas pressure and flow rate. The ozone gas generated by the ozone generator 705 is depressurized to a safe delivery pressure by the second pressure reducing valve 706, and the flow rate is monitored in real time by the first flow meter 707 to achieve precise metering and closed-loop control. The high-temperature gaseous hydrogen peroxide output from the hydrogen peroxide buffer tank 710 is pressure regulated and flow monitored by the third pressure reducing valve 711 and the second flow meter 712. The two oxidizing gases then enter the mixer 714, where the ozone to hydrogen peroxide volume concentration ratio is 0.4-0.6:1, and the ozone to NO volume concentration ratio in the flue gas is 0.2-0.5:1. This mixer adopts a multi-stage Venturi or static mixing structure to fully turbulently mix O3 and H2O2 gases, forming a composite oxidant system with super oxidizing power. Studies have shown that the synergistic effect of O3 and H2O2 can trigger a chain reaction, generating a large number of hydroxyl radicals (·OH), which can significantly improve the oxidation efficiency of NO and recalcitrant organic matter. The mixed oxidizing gas is further stabilized by the fourth pressure reducing valve 715, and then driven by the third blower 713 (such as a corrosion-resistant Roots blower or centrifugal blower) to be transported through pipeline to the flue gas inlet section of the dry reactor 200, where it is rapidly mixed with the high-temperature flue gas.

[0039] This technical solution employs a dual-source design of oxygen and compressed air to ensure continuous and stable operation of the ozone system; the cooling water system effectively controls temperature, extending the service life of the ozone generator; multi-stage pressure reduction and flow meter configuration enable on-demand addition of oxidant, avoiding waste and byproduct generation; the combined use of O3 and H2O2 generates ·OH free radicals, significantly improving the oxidation efficiency of NO and organic pollutants; the heating and pressure reduction design prevents H2O2 from condensing or crystallizing, ensuring smooth system operation.

[0040] Specifically, the flue gas outlet section of the dry reactor 200 is connected to a reducing agent delivery module 800 for supplying reducing agent into the integrated dust collector 300; the outlet section of the integrated dust collector 300 is connected to the chimney 500. For example, as shown... Figure 1 and Figure 5 As shown, after the flue gas leaves the dry reactor 200, the initial removal of acidic gases (such as SO2 and HCl) and some trace pollutants (such as Hg and dioxins) has been completed. At this time, the flue gas still contains a certain concentration of nitrogen oxides (NOx). x The reducing agent delivery module 800 injects a reducing agent (such as ammonia or urea solution) into the flue gas through an atomizing nozzle at the outlet section of the dry reactor 200, ensuring thorough mixing with the flue gas. Under high temperature, the reducing agent rapidly decomposes to generate gaseous ammonia (NH3). The generated NH3 enters the integrated dust collector 300 along with the flue gas and is then reacted with NO in its built-in catalytic filter bag. x Selective catalytic reduction (SCR) reaction occurs. While completing the catalytic reaction, the surface of the catalytic filter bag continuously and efficiently filters particulate matter such as dust, unreacted deacidification byproducts (such as CaSO3 and CaCl2), and activated carbon powder adsorbed with heavy metals and dioxins from the flue gas. The dust layer formed can further adsorb residual pollutants, ultimately achieving synergistic purification of multiple pollutants.

[0041] Using this technical solution, the integrated dust collector 300 not only possesses traditional dust removal functions, but also integrates catalytic denitrification, secondary adsorption, and reaction functions, achieving the removal of particulate matter and SO2. x NO x The system employs synergistic deep purification of multiple pollutants such as Hg and dioxins, and the purified flue gas is ultimately discharged through a chimney at a level of 500 meters to meet emission standards.

[0042] In some embodiments, the reducing agent delivery module 800 includes a storage tank (such as an ammonia water storage tank 801) for storing liquid ammonia or ammonia water, an ammonia water evaporator 802 for evaporating ammonia water to generate ammonia gas, an ammonia gas buffer tank 803 for storing gaseous ammonia, an ammonia gas mixer 804 for mixing ammonia gas with air and diluting it to a safe concentration, a third flow meter 806 for detecting the mixed gas, and a dilution fan 805 for providing dilution air and delivering the diluted mixed gas to the downstream flue. For example, Figure 1 and Figure 5 As shown, a 5%-20% concentration ammonia solution (NH3H2O) is first stored in ammonia storage tank 801. This tank is a closed container under normal or low pressure, equipped with a level gauge, temperature sensor, and safety relief device to prevent evaporation and leakage, ensuring storage safety. When the system needs to add a reducing agent, ammonia is drawn from the storage tank by a metering pump (such as a diaphragm pump) and quantitatively delivered to the ammonia evaporator 802. The evaporator uses an external heat source (such as steam, waste heat from flue gas, or electric heating) to heat the ammonia to above its boiling point, allowing it to fully evaporate and decompose. The resulting high-temperature ammonia gas and water vapor mixture enters the ammonia buffer tank 803 for gas-liquid separation and pressure stabilization. The buffer tank serves to stabilize pressure, buffer, and regulate instantaneous flow fluctuations, ensuring a continuous and uniform subsequent ammonia supply. The ammonia gas exiting the buffer tank enters the ammonia mixer 804, where it is mixed with clean air introduced by the dilution fan 805. A dilution fan draws ambient air or preheated air from the boiler to dilute the ammonia gas to a volume concentration below 5% (typically controlled at 3%-4%), below the lower explosive limit (LEL, the explosive limit of ammonia is 15%-28%), ensuring inherent safety during transport and injection. The diluted ammonia gas mixture is then piped to the flue gas outlet section of the dry reactor 200 or the inlet flue of the integrated dust collector 300, where it is thoroughly mixed with the flue gas before entering the catalytic filter bag area. Here, ammonia (NH3) acts as a reducing agent, reacting with nitrogen oxides (NOx) in the flue gas under the action of the catalyst loaded within the catalytic filter bag. x Selective catalytic reduction reaction occurs, achieving efficient denitrification.

[0043] This technical solution uses ammonia water (not anhydrous liquid ammonia) as a reducing agent, resulting in low storage and operational risks. The ammonia gas is transported after being fully diluted to avoid explosions or corrosion caused by excessively high local concentrations. This achieves safe, stable, and precise addition of the reducing agent, providing a reliable guarantee for the efficient denitrification of the catalytic filter bag.

[0044] In some embodiments, the catalytic filter bag is loaded with a composite catalyst. For example, such as... Figure 1 As shown, the composite catalyst, through multi-component synergistic design, not only possesses high-efficiency denitrification (NO)... x In addition to its reducing ability, the composite catalyst also possesses resistance to sulfur and alkali metal poisoning, as well as the function of promoting the decomposition of oxidizing pollutants, thus adapting to long-term stable operation under complex flue gas conditions. Furthermore, this composite catalyst can be loaded onto the fiber surface of the catalytic filter bag via sol-gel method, impregnation method, or co-precipitation method. For example, PPS or PTFE-based filter media can be immersed in a sol solution containing vanadium, tungsten, and molybdenum precursors, and after drying and calcination, a uniform and firm catalytic coating is formed, ensuring that it does not easily fall off during long-term pulse cleaning.

[0045] By using this technical solution, and loading composite catalysts such as V2O5-WO3-MoO3 / TiO2 onto the catalytic filter bag, not only is the denitrification efficiency and operational stability improved, but the ability to synergistically treat multiple pollutants is also expanded, significantly enhancing the adaptability and reliability of the flue gas multi-pollutant synergistic treatment system.

[0046] In some embodiments, the support of the composite catalyst is composed of at least one of TiO2, SiO2, Al2O3, and molecular sieves, or at least one of a complex of two or more of TiO2, SiO2, Al2O3, and molecular sieves; the active component of the composite catalyst is composed of V2O5 and / or WO3; the dopant of the composite catalyst is composed of at least one of Fe2O3, Nb2O5, CeO2, Sb2O3, and SnO2; the catalyst contains 5-20% support, wherein the TiO2 content is at least 3-12%, and contains 1-10% V2O5 and 0.1-8% WO3, and contains 0.1-2% Fe2O3 or 1.5-3% Nb2O5 or 3-5% Sb2O3 or 2-4% SnO2. For example, Figure 1 As shown, the composite catalyst uses a TiO2-SiO2 composite support and is prepared by impregnation, exhibiting a uniform mesoporous structure that facilitates the dispersion of active components. V2O5 and WO3 are loaded onto this support as the main active components; then SnO2 is doped as an auxiliary agent. During the catalytic denitrification process, V2O5, as the core active component, provides abundant acidic and redox sites, activating NH3 molecules and promoting their reaction with NO. x The reaction; WO3 improves the adsorption and stability of NH3; the TiO2-SiO2 composite support has good thermal stability and water resistance, preventing the catalyst from sintering or deactivating during long-term operation. SnO2 forms a solid solution or interfacial structure with V2O5 or WO3, regulating the electronic state of the metal oxide and enhancing the redox ability of the catalyst; During long-term operation, catalytic filter bags may become deactivated due to the following reasons: dust clogging or covering of active sites; organic matter deposition on the surface; ammonium bisulfate (NH4HSO4) condensation covering the catalyst in the low-temperature zone; and poisoning by trace heavy metals or chlorides. Regeneration should be performed at least once a year, with each regeneration lasting 4-8 hours. During regeneration, a low concentration of ozone (O3) or hydrogen peroxide (H2O2) vapor can be introduced to assist in restoring catalyst activity. SnO2 can catalyze the decomposition of ozone, deeply oxidizing carbon deposits, tar, or adsorbed organic pollutants (such as dioxin precursors) on the filter bag surface into CO2 and H2O, achieving self-cleaning and regeneration; simultaneously, it forms oxidation active sites on the catalyst surface, and O3 can partially oxidize NH4 in NH4HSO4. + Or it may promote its thermal decomposition; achieve oxidative pyrolysis at low temperature (200 °C) rather than simple pyrolysis.

[0047] Using this technical solution, the catalyst exhibits high denitrification efficiency and operational stability during the denitrification process. Furthermore, when the catalyst is deactivated and oxidant is introduced to regenerate the catalytic filter bag, it can also support low-temperature catalytic regeneration, thus extending the service life of the filter bag.

[0048] In some embodiments, the integrated dust collector 300 outlet is provided with a main flue 310 and a bypass flue 320. The bypass flue 320 is provided with a fixed adsorption module 900, which is used to adsorb regeneration exhaust gas during the regeneration of the catalytic filter bag. The outlet of the fixed adsorption module is connected to the chimney 500. For example, Figure 1 and Figure 6 As shown, during normal system operation, the purified flue gas directly enters the chimney 500 through the main flue 310 to achieve compliant emissions. At this time, the bypass flue 320 is closed to ensure minimal system resistance and maximum operating efficiency. When the catalytic filter bag's denitrification efficiency decreases due to dust blockage, organic matter deposition, ammonium bisulfate condensation, or trace heavy metal / chloride poisoning after a period of operation, online or offline regeneration of the catalytic filter bag is required. During regeneration, low-concentration ozone or hydrogen peroxide vapor is introduced into the integrated dust collector 300, and an oxidative cracking reaction is carried out under heating or ambient temperature conditions, releasing gases containing volatile organic compounds (VOCs), CO, and NO. x SO x The system generates regeneration exhaust gas containing unreacted ozone and other components. Directly discharging this exhaust gas into the chimney could cause short-term emissions exceeding standards. Therefore, when the system initiates the regeneration process, it automatically switches the flue gas flow direction: closing the main flue 310 and opening the bypass flue 320. This directs the exhaust gas generated during regeneration to bypass the main emission path and into the fixed adsorption module 900 within the bypass flue 320. The fixed adsorption module 900 is filled with high-performance adsorbents, such as modified activated carbon, molecular sieves, alkaline adsorbents, and activated coke, which can efficiently adsorb O3, VOCs, dioxins, and some acidic gases. As the regeneration exhaust gas passes through the fixed adsorption module 900, harmful pollutants are adsorbed and retained stage by stage, achieving purification. The clean gas flow after adsorption and purification is discharged from the desorbed gas outlet of the fixed adsorption module 900 and directly connected to the chimney 500 for safe emission. After the adsorbent becomes saturated, the fixed adsorption module 900 can be desorbed and regenerated. For example, hot nitrogen or steam can be used to desorb the adsorbent, releasing high-concentration pollutant gases, which can then be sent to the front-end combustion chamber or a matching small catalytic oxidation device for complete decomposition. After desorption, the adsorbent regains its adsorption capacity and can be reused in the next cycle, achieving recycling.

[0049] By adopting this technical solution, a bypass flue 320 with a fixed adsorption module 900 is set up to realize closed-loop or semi-closed-loop treatment in the catalytic filter bag regeneration process, effectively avoiding secondary pollution of the environment by the regeneration exhaust gas, ensuring continuous compliance with emission standards under all operating conditions, and improving the overall environmental compliance and operational safety.

[0050] In some embodiments, the main flue duct 310 is further provided with a flue gas waste heat utilization module 420, the outlet of which is connected to the chimney 500 and / or the fixed adsorption module 900. For example, Figure 1 As shown, the flue gas waste heat utilization module 420 can be a heat pipe heat exchanger, a waste heat boiler economizer, etc. Its inlet is connected to the main flue duct 310 of the integrated dust collector 300 outlet. It is used to recover the low-grade heat energy remaining in the purified flue gas for heating boiler feedwater, heating, industrial hot water, or driving a small power generation system, thereby improving the energy utilization efficiency of the entire flue gas treatment system. During normal operation of the system, after being purified by the integrated dust collector 300, the flue gas enters the flue gas waste heat utilization module 420 through the main flue duct 310, where it releases heat and its temperature is further reduced to 100-130 ℃. At this time, according to the system operation requirements, the outlet of the flue gas waste heat utilization module 420 can be selectively connected to the chimney 500 to directly discharge the cooled clean flue gas, which is suitable for normal operating conditions without bypass operation; during the regeneration of the catalytic filter bag, the outlet of the flue gas waste heat utilization module 420 is connected to the bypass flue 320. During regeneration, the flue gas temperature needs to be maintained at about 220 ℃, which requires additional heating of the flue gas. At this time, the additional heat carried by the flue gas and exhaust gas during regeneration is recovered by the flue gas waste heat utilization module 420, and the exhaust gas during regeneration is adsorbed and fixed in the fixed adsorption module 900 of the bypass flue 320.

[0051] By adopting this technical solution, by setting a flue gas waste heat utilization module 420 in the main flue duct 310 and connecting its outlet to the chimney 500 and / or the fixed adsorption module 900, not only is the efficient recovery and utilization of flue gas waste heat achieved and the system energy consumption is reduced, but also a suitable reaction temperature is increased for the regeneration tail gas at the dust removal outlet of the fixed adsorption module 900, realizing closed-loop treatment of energy recovery and adsorbent purification of pollutants.

[0052] In some embodiments, the fixed adsorption module 900 includes a first isolation valve 901 located in the main flue 310, a second isolation valve 902 located in the bypass flue 320, a fixed adsorption bed 903, a first control valve 904 connected to the fixed adsorption bed 903 for discharging desorbed gas, a fourth flow meter 905 for detecting the flow rate of heating gas during desorption, and a heater 906 for heating the gas; the adsorbent of the fixed adsorption bed 903 may be 2-6 mm granular activated carbon or molecular sieve, and the adsorbent loading per unit flue gas treatment is 100-250 mg / Nm³. 3The residence time of flue gas in the fixed bed is 0.3-0.8 s. For example, such as... Figure 1 and Figure 6 As shown, this module is integrated into the flue gas path at the outlet of the integrated dust collector 300. It is used to treat the regeneration tail gas during the regeneration of the catalytic filter bags, preventing instantaneous excessive emissions of pollutants. During normal system operation, the flue gas, after being purified by the integrated dust collector 300, flows to the chimney 500 through the main flue duct 310. At this time: the first isolation valve 901 is in the open state, ensuring the main flue is unobstructed; the second isolation valve 902 is in the closed state, isolating the bypass flue duct 320; the first control valve 904 is closed, and the fixed adsorption bed 903 is in standby state. The flue gas flows smoothly through the main flue duct 310, achieving low resistance and high-efficiency emissions. When the catalytic filter bags in the integrated dust collector 300 need to be regenerated (e.g., due to ammonium bisulfate deposition, organic carbon buildup, or active site poisoning leading to a decrease in denitrification efficiency), the system switches to regeneration mode. At this time: the first isolation valve 901 closes, cutting off the emission path of the main flue 310; the second isolation valve 902 opens, guiding the flue gas or regeneration gas flow into the bypass flue 320; the regeneration gas (such as ozone O3, high-temperature flue gas or carrier gas) enters the integrated dust collector 300, performing oxidative or thermal regeneration on the catalytic filter bag, releasing unreacted O3, volatile organic compounds (VOCs), CO, NH3, SO2, etc. x and trace amounts of NO x The regenerated exhaust gas is carried by the airflow into the bypass flue 320 and then into the fixed adsorption bed 903. The fixed adsorption bed is filled with high-performance adsorption materials, such as modified activated carbon, molecular sieves (e.g., 13X or ZSM-5), alkaline impregnated carbon, or alumina. As the regenerated exhaust gas passes through the fixed adsorption bed 903, harmful components are adsorbed and retained stage by stage, achieving purification. The purified gas can be directly discharged or further used in subsequent processes. After the fixed adsorption bed 903 has been running for a period of time, the adsorbent tends to become saturated and desorption regeneration is required. At this time: the second isolation valve 902 is closed to isolate the regeneration gas source; the desorption program is started, and the heater 906 is started to heat the clean gas; the heated gas enters the fixed adsorption bed 903 after being measured by the fourth flow meter 905 for thermal purging; the adsorbed pollutants are desorbed to form high-concentration desorbed gas; the first control valve 904 is opened to deliver the desorbed gas to the outlet of the front-end waste heat boiler or a dedicated oxidation device, where it is completely decomposed into harmless substances such as CO2, H2O, and N2 at high temperatures to avoid secondary pollution.

[0053] This technical solution effectively intercepts pollutants in the regeneration exhaust gas during catalytic filter bag regeneration, avoiding instantaneous emissions exceeding standards and meeting environmental continuous monitoring requirements. Seamless switching between the main and bypass circuits is achieved through the coordinated control of the first isolation valve 901 and the second isolation valve 902, resulting in a high degree of system automation. The fixed adsorption bed 903 is reusable, reducing operating costs. Centralized treatment of desorbed gas enables closed-loop management. The integrated design of the fixed adsorption module 900 with the main flue 310 and bypass flue 320 saves space and facilitates maintenance.

[0054] In some embodiments, the inlet end of the bypass flue 320 is located on the main flue 310 downstream of the outlet of the flue gas waste heat utilization module 420. For example, as shown... Figure 1 As shown, the main flue duct 310 is equipped with a flue gas waste heat recovery module 420. Regardless of whether the flue gas is discharged through the main duct or enters the bypass duct for regeneration, it preferentially passes through the flue gas waste heat recovery module 420 for heat recovery. During normal system operation, the switching valve (such as an electric or pneumatic butterfly valve) on the bypass flue duct 320 is in the closed state, and the purified flue gas flows sequentially through the integrated dust collector 300, the main flue duct 310, the flue gas waste heat recovery module 420, and the chimney 500. During this process, the flue gas waste heat is effectively recovered for heating water supply, heating, or power generation, improving the overall energy efficiency of the system. When it is necessary to regenerate the catalytic filter bag in the integrated dust collector 300 (such as using ozone oxidation for online or offline regeneration), the system automatically switches the operating mode: closing the valve downstream of the main flue duct 310 leading to the chimney; opening the inlet valve of the bypass flue duct 320, thus changing the flue gas flow direction. At this time, the regenerated exhaust gas from the integrated dust collector 300 first enters the flue gas waste heat utilization module 420 through the main flue duct 310 to release residual heat energy. The cooled regenerated exhaust gas then enters the opened bypass flue duct 320 from the outlet of the flue gas waste heat utilization module 420, and then enters the fixed adsorption module 900.

[0055] By adopting this technical solution, the inlet of the bypass flue 320 is set behind the outlet of the flue gas waste heat utilization module 420, realizing the spatiotemporal coordination of heat recovery and pollutant regeneration treatment.

[0056] In some embodiments, the processing system further includes an induced draft fan 410 disposed in the main flue 310, the induced draft fan 410 being located upstream of the flue gas waste heat utilization module 420 in the main flue 310. For example, as... Figure 1As shown, the induced draft fan 410, serving as the negative pressure drive core of the entire flue gas purification system, is installed on the main flue duct 310 after the outlet of the integrated dust collector 300 and before the flue gas waste heat utilization module 420. Its function is to overcome the system resistance in the entire flue gas process, including the pressure drop of the waste heat boiler 100, dry reactor 200, integrated dust collector 300, flue gas waste heat utilization module 420, various conveying pipelines and valves, etc., to ensure that the flue gas can flow stably and continuously from the front combustion chamber or process equipment to the end chimney 500.

[0057] Using this technical solution, after filtration by the integrated dust collector 300, the flue gas temperature is typically 140-180 ℃, which is within the safe operating temperature range of the induced draft fan, eliminating the need for additional cooling. The flue gas has already had most of the dust, acidic components, and harmful pollutants removed, significantly reducing the risk of corrosion, wear, and dust accumulation on the induced draft fan impeller, thus extending equipment lifespan. The induced draft fan 410 draws air from the post-purification stage, keeping the front-end dry reactor 200 and the integrated dust collector 300 operating under negative pressure, which helps prevent the leakage of unpurified flue gas and ensures a safe workshop environment.

[0058] In some embodiments, the integrated dust collector outlet is further provided with a hot flue gas passage 330, which is connected to a heat recovery device for recovering waste heat from the flue gas. For example, such as... Figure 1 As shown, the flue gas purified by the integrated dust collector 300 still has a high temperature and considerable waste heat recovery value. Therefore, a hot flue gas channel 330 is set at the outlet section of the integrated dust collector 300. This channel draws high-temperature purified flue gas from upstream of the main flue 310 or the bypass flue 320 and transports it to an external heat-using device to realize the cascade utilization of energy.

[0059] By adopting this technical solution and setting up a hot flue gas channel 330 and connecting it to a general heating device, not only is the comprehensive utilization efficiency of flue gas waste heat improved and the system energy consumption and carbon emissions reduced, but the energy flexibility and economy of the entire flue gas treatment system are also enhanced. It is especially suitable for application scenarios with high requirements for energy utilization efficiency, such as combined heat and power generation and centralized heating in industrial parks.

[0060] In some embodiments, the heating devices connected to the hot smoke channel 330 include a hydrogen peroxide heater 709 in the oxidant delivery module 700, an ammonia evaporator 802 in the reducing agent delivery module 800, and a heater 906 in the fixed adsorption module 900. The hot smoke channel 330 includes three branches, which are respectively connected to the above three. The hydrogen peroxide heater 709 is equipped with a fifth flow meter 717 connected to the hot smoke channel 330 for detecting the hot smoke flow rate and a second control valve 716 for opening and closing the corresponding branch of the hot smoke channel 330. The ammonia evaporator 802 is equipped with a sixth flow meter 808 connected to the hot smoke channel 330 for detecting the hot smoke flow rate and a third control valve 807 for opening and closing the corresponding branch of the hot smoke channel 330. The heater 906 is equipped with a fourth control valve 907 connected to the hot smoke channel 330 for opening and closing the corresponding branch of the hot smoke channel 330. For example, Figure 1 and Figures 4-6 As shown, the hot flue gas channel 330 is led out from the main flue gas 310 at the outlet of the integrated dust collector 300, using high-temperature purified flue gas with a temperature of 140-180 ℃ as a heat source. The hot flue gas channel 330 is equipped with a main control valve before each branch and is divided into three independent branches. Each branch is equipped with a dedicated control valve and flow monitoring device to achieve on-demand heating and precise control: The first branch serves the hydrogen peroxide heater 709 (oxidant system). The first branch of the hot flue gas channel 330 is connected to the heating chamber of the hydrogen peroxide heater 709, providing it with the heat energy required for evaporating the H2O2 solution. The second control valve 716 is installed on this branch to open and close the hot flue gas channel 330. It automatically opens when the system needs to start the hydrogen peroxide evaporation function and closes when the addition stops. The fifth flow meter 717 monitors the flow rate of the hot flue gas entering the hydrogen peroxide heater 709 in real time and feeds it back to the central control system to adjust the opening of the second control valve 716 to ensure stable heating. The second branch serves the ammonia evaporator 802 (reducing agent system). The second branch of the hot flue gas passage 330 is connected to the ammonia evaporator 802, providing it with the heat source required for ammonia evaporation. The third control valve 807 controls the on / off state of this branch. It opens when the denitrification system needs ammonia injection and closes otherwise, achieving on-demand heating. The sixth flow meter 808 monitors the hot flue gas flow rate, supports closed-loop control, and ensures that the ammonia evaporation rate is consistent with the flue gas NO₂. x Load matching. The third branch serves heater 906 (fixed adsorption module). The third branch of the hot flue gas passage 330 is connected to heater 906 of fixed adsorption module 900 to provide hot purge gas during adsorption bed desorption and regeneration. The fourth control valve 907 controls the opening and closing of this branch. It is only opened when fixed adsorption bed 903 needs desorption and regeneration, and closed at other times to prevent accidental heat input.

[0061] Using this technical solution, the hot flue gas channel 330 realizes the distributed and on-demand utilization of waste heat in multiple subsystems, converting the originally discharged low-grade heat energy into process heat source, significantly improving the overall energy efficiency of the system; each branch achieves independent start-up and precise control through control valves (716, 807, 907) and flow meters (717, 808), and the central control system can dynamically allocate heat according to the operating status of each module (such as whether regeneration is required, whether oxidant / reducing agent is added), avoiding energy waste.

[0062] Secondly, this application provides a method for the synergistic treatment of multiple pollutants in flue gas, which employs the aforementioned treatment system and is applied to the flue gas treatment of a 500 t / d waste incineration plant. The main parameters of the flue gas from this plant are designed as shown in the table below: Table 1. Main parameters of flue gas (standard conditions, dry basis, 11% O2)

[0063] The methods for treating the above-mentioned flue gas include: First, the waste incineration flue gas undergoes SNCR (Selective Non-Catalytic Reduction) and in-furnace desulfurization within the incinerator. This involves injecting a reducing agent (ammonia, urea solution, or solid denitrification agent) and desulfurizing agent powder (calcium carbonate, calcium magnesium acetate) within a temperature window of 800-950 °C to achieve preliminary removal of nitrogen oxides and sulfur oxides. Then, high-temperature flue gas (approximately 180 °C) emitted from the waste heat boiler 100 is introduced into the dry reactor 200. In this reactor, it is thoroughly mixed with sodium bicarbonate desulfurizing agent powder and activated carbon, precisely added via the desulfurizing agent delivery module 610 and activated carbon delivery module 620, thereby simultaneously carrying out a preliminary desulfurization reaction and efficiently achieving the adsorption of heavy metals and the effective removal of dioxin-like pollutants. The reducing agent delivery module 800 uses 20% ammonia water, which is adjusted to 5% ammonia gas through an ammonia water evaporator. After being mixed evenly with high-temperature flue gas at the outlet of the dry reactor 200, it enters the integrated dust collector 300. In the integrated dust collector 300, particulate matter, deacidifying agent and activated carbon in the flue gas adhere to the surface of the filter bag, and further deacidification, heavy metal and dioxin removal reactions occur. Meanwhile, ammonia molecules enter the inner layer of the filter bag and, under the action of the catalyst (using a V-Sn-Ti catalyst system), undergo a redox reaction with NOx, ultimately achieving the synergistic treatment of multiple pollutants.

[0064] After the integrated dust collector 300 has been running for half a year, the inlet temperature of the dry reactor 200 is raised to 225 ℃ by adjusting the economizer of the waste heat boiler 100, and the oxidant delivery module 700 is run continuously for 24 hours to complete the catalyst regeneration. The oxidant added is a mixture of O3 and H2O2, with the volume concentration ratio of the two adjusted to 0.5, and the volume concentration ratio of O3 to NO in the flue gas is 0.4. The oxidant delivery flow rate is calculated according to formulas (11) and (12). At this time, the NO oxidation rate is about 50%, and it will not be over-oxidized into higher-order N2O5 byproducts. After oxidation, the ratio of NO to NO2 in the flue gas is about 1:1, which meets the "fast SCR" reaction principle. Combined with the Sn2O3 component added to the catalyst, the thermal decomposition temperature threshold of ammonium sulfate can be significantly reduced from the conventional 350 ℃ to about 200 ℃, thereby effectively activating the catalyst regeneration performance.

[0065] If the deacidifying agent is purchased as 200-mesh coarse sodium bicarbonate powder, and after grinding it into 600-mesh fine sodium bicarbonate powder, and the excess coefficient is 1.1, then according to the original concentration and control standard of acidic pollutants, the sodium bicarbonate addition flow rate is calculated to be 204 kg / h using formula (6). If a high specific surface area (>40 m²) is purchased... 2 If the acidification reaction is carried out by / g) and the excess coefficient is 1.8, the hydrated lime addition flow rate is calculated to be 147 kg / h according to formula (7).

[0066] F NaHCO3 ={2.62(F SO2in -F SO2out )+2.30(F HClin -F HClout )}×SR Na --(6) F CaOH2 ={1.16(F SO2in -F SO2out )+1.01(F HClin -F HClout )}×SR Ca --(7) In the formula: F NaHCO3 F CaOH2 F represents the mass flow rate of the deacidifying agent injected, expressed in kg / h. SO2in F HClin F represents the mass flow rates of SO2 and HCl in the original flue gas, expressed in kg / h. SO2out F HClout SR is the mass flow rate in the clean flue gas, expressed in kg / h; SR is the ratio of the actual amount of deacidifying agent used to the theoretical amount used.

[0067] The fly ash yield after deacidification can be calculated based on the deacidification reaction principle formulas (1)-(5) of baking soda and slaked lime (which is equal to the sum of the deacidification reaction products and the oversprayed deacidification agent). Taking the calculation of fly ash after deacidification with baking soda as an example, the main reactants of baking soda deacidification are NaCl and Na2SO4. The calculation formulas for the amount of reactants produced are shown in (8) and (9), and the calculation formula for the amount of baking soda oversprayed is shown in (10): M NaCl =2.30 (F HClin -F HClout )×58.5 / 84--(8) M Na2SO4 =2.62 (F SO2in -F SO2out )×142 / 84--(9) M 过量小苏打 =F NaHCO3 ×(SR Na -1)÷S Na R--(10) Where: M NaCl M Na2SO4 M represents the reaction yield of NaCl and Na₂SO₄, expressed in kg / h. 过量小苏打 The amount of baking soda consumed due to excessive spraying is expressed in kg / h.

[0068] Based on the above formula, a simple calculation shows that the fly ash production from sodium bicarbonate deacidification is 155 kg / h. Similarly, the fly ash production from high-specific-weight slaked lime deacidification is 190 kg / h. Furthermore, it is known that the excess coefficient of ordinary slaked lime in the conventional "SDA + dry method" deacidification process is between 2 and 2.5. If the excess coefficient is calculated as 2, the fly ash production of the conventional process is 207 kg / h. Therefore, the fly ash production from deacidification using a dry reactor can be reduced by 8-27% compared to the conventional process, thus saving on fly ash treatment costs.

[0069] F O3 =(C NO ×48 / 30)×M×Q×0.000001--(11) F H2O2 =(C NO (×18 / 30)×M / N×Q÷C H2O2 ×0.000001--(12) In the formula: F O3 F H2O2 The flow rates of O3 and H2O2 are expressed in kg / h; C NO The original concentration of NO in the flue gas, in mg / Nm³. 3 Q represents flue gas flow rate, in Nm³. 3 / h; M and N are the volume concentration ratios of O3 / NO and O3 / H2O2, respectively; C H2O2 The concentration of H2O2 solution is expressed in percent.

[0070] During the regeneration operation of the integrated dust collector 300, the outlet flue of the flue gas waste heat utilization module 420 switches from the main flue duct 310 to the bypass flue duct 320. The approximately 215°C flue gas exiting the dust collector passes through the waste heat utilization system, reducing its temperature to 130-150°C before entering the fixed adsorption bed 903 for deep purification of the tail gas. The fixed adsorption bed 903 uses 2-6mm granular activated carbon, with a unit flue gas treatment loading of 150 mg / Nm³. 3 The total loading amount is 150 mg / Nm³. 3 ×100000 Nm 3 / h×24 h=360 kg. After the integrated dust collector 300 is regenerated, the economizer temperature outlet is adjusted to 180 ℃, and the outlet of the flue gas waste heat utilization module 420 is adjusted to the main flue duct 310 for operation. After the fixed adsorption bed 903 has been running for a period of time, the hot flue gas pipeline valve of the adsorbent is opened, and its temperature is raised to 300 ℃ by the electric heater 906 to complete the adsorbent desorption and regeneration. The desorbed gas contains dioxins and a small amount of acidic gas, which is returned to the inlet flue of the dry reactor 200 for further purification.

[0071] This application innovatively integrates dry desulfurization, catalytic filtration, and regeneration technologies to form a short-path flue gas purification process. This achieves efficient and synergistic removal of multiple pollutants in flue gas, reducing redundant equipment configuration and flue gas resistance, significantly lowering equipment investment, floor space costs, and operating costs. The addition of a catalytic filter bag regeneration device allows for periodic regeneration, restoring catalytic activity and filtration performance, reducing replacement frequency, and simultaneously improving flue gas pollutant emission indicators, balancing economic efficiency and environmental performance. The regeneration system in this application is easy to operate, quick to learn, and highly efficient, demonstrating significant practical value. The addition of an adsorption fixed bed and its regeneration device can be used for dioxin removal during catalytic filter bag regeneration, reducing environmental risks, extending adsorbent lifespan, and lowering operating costs. This application uses a high-efficiency dry reactor to completely replace the traditional "SDA (slaked lime slurry) + dry (slaked lime / baking soda)" desulfurization process. Utilizing highly active desulfurizing agents (baking soda, high-ratio slaked lime), optimizing the desulfurization reaction temperature, and increasing gas-solid contact time significantly improves desulfurization efficiency, meeting the requirement of catalytic filter bags with an inlet SO2 concentration <10 mg / Nm³. 3 This application addresses high requirements while improving the utilization rate of deacidifying agents and reducing fly ash production. It is compatible with the design of rapid technical upgrade systems for existing incineration plants, can be integrated with the existing waste incineration plant's process flow, shortens the technical upgrade period, avoids losses from prolonged shutdowns, and is particularly suitable for energy-saving and environmentally friendly upgrades of older facilities.

[0072] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0073] Furthermore, it should be noted that the scope of the methods and apparatus in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

[0074] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A flue gas multi-pollutant co-processing system, characterized in that, The system includes a waste heat boiler (100), a dry reactor (200), an integrated dust collector (300), a waste heat utilization module (420), and a chimney (500) connected in sequence along the flue gas flow direction. The integrated dust collector (300) has a built-in catalytic filter bag; The flue gas inlet section of the dry reactor (200) is connected to an oxidant delivery module (700) for delivering an oxidant into the dry reactor (200), a deacidifying agent delivery module (610) for delivering a deacidifying agent into the dry reactor (200), and an activated carbon delivery module (620) for delivering activated carbon into the dry reactor (200); the flue gas outlet section of the dry reactor (200) is connected to a useful reducing agent delivery module (800), which is used to reduce the flue gas at the outlet of the dry reactor (200).

2. The flue gas multi-pollutant co- treatment system according to claim 1, wherein, The flue gas waste heat utilization module (420) is provided with a main flue (310) and a bypass flue (320) at its outlet. The bypass flue (320) is provided with a fixed adsorption module (900). The fixed adsorption module (900) is used to adsorb the regeneration tail gas when regenerating the catalytic filter bag. The outlet of the fixed adsorption module (900) is connected to the chimney (500). The outlet of the flue gas waste heat utilization module (420) is connected to the chimney (500) and / or the fixed adsorption module (900). The inlet end of the bypass flue (320) is located on the main flue (310) behind the outlet of the flue gas waste heat utilization module (420).

3. The flue gas multi-pollutant co- treatment system according to claim 2, wherein, The fixed adsorption module (900) includes a first isolation valve (901) located in the main flue (310), a second isolation valve (902) located in the bypass flue (320), and a fixed adsorption bed (903). The fixed adsorption bed (903) is provided with a first control valve (904) for discharging desorbed gas. The first control valve (904) is also connected to the inlet of the dry reactor (200).

4. The flue gas multi-pollutant co- treatment system according to claim 1, wherein, The integrated dust collector (300) is also provided with a hot flue gas channel (330) at its outlet. The hot flue gas channel (330) is connected to a heat recovery device to recover heat from the flue gas.

5. The flue gas multi-pollutant co- treatment system according to claim 4, wherein, The oxidant delivery module (700) includes an ozone generation system and a hydrogen peroxide evaporation system; The ozone generation system includes an oxygen tank (701) for storing and supplying oxygen, and a compressed air inlet pipe (702) for serving as a backup oxygen source. The oxygen tank (701) and the compressed air inlet pipe (702) are connected to an ozone generator (705), which is connected to a cooling water system (704). The hydrogen peroxide evaporation system includes a hydrogen peroxide raw water tank (708) for storing hydrogen peroxide, a hydrogen peroxide heater (709) for heating the hydrogen peroxide in the hydrogen peroxide raw water tank (708), and a hydrogen peroxide buffer tank (710) for storing gaseous hydrogen peroxide. The outlet of the ozone generator (705) is connected to the outlet of the hydrogen peroxide buffer tank (710) and the inlet of the mixer (714). The mixer (714) is used to fully mix gaseous ozone and gaseous hydrogen peroxide in proportion and then send them into the dry reactor (200). And / or, the hot flue (330) is connected to the hydrogen peroxide heater (709).

6. The flue gas multi-pollutant co- treatment system according to claim 4, wherein, The reducing agent delivery module (800) includes a storage tank (801) for storing liquid ammonia or ammonia water, an ammonia water evaporator (802) for evaporating ammonia water to generate ammonia gas, an ammonia gas buffer tank (803) for storing gaseous ammonia, and an ammonia gas mixer (804) for mixing ammonia gas with air and diluting it to a safe concentration before sending the mixed gas into the integrated dust collector (300). And / or, the hot flue (330) is connected to the ammonia evaporator (802).

7. The flue gas multi-pollutant co-operative treatment system according to claim 1, wherein, The deacidifying agent conveying module (610) includes a deacidifying agent storage silo (611) for storing deacidifying agent, a coarse powder quantitative conveying device (612) for quantitatively conveying coarse powder deacidifying agent, a fine powder mill (613) for grinding coarse powder deacidifying agent into fine powder, a deacidifying agent fine powder silo (614) for storing deacidifying agent fine powder, and a fine powder quantitative conveying device (616) for quantitatively conveying fine powder deacidifying agent into the dry reactor (200).

8. The flue gas multi-pollutant co-operative treatment system according to claim 1, wherein, The activated carbon conveying module (620) includes an activated carbon raw material storage bin (621) for storing activated carbon and an activated carbon metering conveying device (622) for metering activated carbon into the dry reactor (200).

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