Flue gas co-reaction device and flue gas dust removal, desulfurization and denitrification control method

Abstract

This application provides a flue gas co-reaction device and a flue gas dust removal, desulfurization, and denitrification control method. The flue gas co-reaction device includes an upstream pipe and a downstream pipe respectively located upstream and downstream of a reaction chamber. An inertial dust collector is installed at the first end of the upstream pipe, and a desulfurization absorbent atomizing nozzle is installed within the upstream pipe. The reaction chamber includes multiple first reaction sub-chambers, each containing an ion cascade dust collector, a hopper, and a denitrification absorbent atomizing nozzle. The hopper is located at the bottom of the ion cascade dust collector, and the denitrification absorbent atomizing nozzle is located at the top of the ion cascade dust collector. A denitrification catalyst assembly is installed in the downstream pipe at its inlet. The denitrification catalyst assembly includes multiple layers of denitrification catalyst for completing the denitrification reaction. Thus, the above device can simultaneously complete dust removal, desulfurization, and denitrification, thereby reducing equipment installation space and saving industrial land.

Description

Technical Field

[0001] This application relates to the field of industrial dust removal technology, specifically to a flue gas synergistic reaction device and a flue gas dust removal, desulfurization, and denitrification control method. Background Technology

[0002] In the non-ferrous metallurgy and power industries, in order to meet the environmental protection requirements for flue gas emissions, it is usually necessary to remove particulate matter, nitrogen oxides and sulfur dioxide from the flue gas.

[0003] For particulate matter in flue gas, electrostatic precipitators, bag filters, or a combination of electrostatic and bag filters are commonly used to remove particulate matter. For nitrogen oxides in flue gas, denitrification treatment is typically performed using methods such as SCR or SNCR. For sulfur dioxide in flue gas, desulfurization treatment using a limestone-gypsum wet process is usually required.

[0004] However, since denitrification, desulfurization and dust removal each require their own independent equipment, they occupy a large amount of installation space and industrial land, resulting in high requirements for the manufacturing, installation and operation of flue gas purification.

[0005] Application content

[0006] This application provides a flue gas co-reaction device and a flue gas dust removal, desulfurization and denitrification control method, which can solve the problems of large industrial land occupation and high flue gas purification costs in related technologies.

[0007] To solve the above-mentioned technical problems, this application is implemented as follows:

[0008] In a first aspect, embodiments of this application provide a flue gas co-reaction device for dust removal, desulfurization and denitrification of flue gas, the flue gas co-reaction device including an upstream pipeline, a reaction chamber and a downstream pipeline;

[0009] The upstream pipe and the downstream pipe are respectively located upstream and downstream of the reaction chamber, and the reaction chamber is connected to the upstream pipe and the downstream pipe;

[0010] An inertial dust collector is installed at the first end of the upstream pipeline, and a desulfurization absorbent atomizing nozzle is installed in the upstream pipeline. The first end of the upstream pipeline is the end of the upstream pipeline that is away from the reaction chamber.

[0011] The reaction chamber includes multiple first reaction sub-chambers. Each first reaction sub-chamber is provided with an ion cascade dust collection electrode, a hopper, and a denitrification absorbent atomizing nozzle. The hopper is located at the bottom of the ion cascade dust collection electrode, and the denitrification absorbent atomizing nozzle is located at the top of the ion cascade dust collection electrode.

[0012] A denitrification catalyst assembly is installed in the downstream pipeline. The denitrification catalyst assembly is located at the inlet of the downstream pipeline and includes multiple denitrification catalyst layers for completing the denitrification reaction.

[0013] Optionally, the flue gas co-reaction device further includes an acetylene explosion cleaning component;

[0014] The acetylene explosion cleaning assembly is located outside the reaction chamber and is connected to the ion cascade dust collection electrode.

[0015] Optionally, the reaction chamber includes multiple flow guide baffles;

[0016] The flow guide baffle is fixed on the inner wall of the reaction chamber, and each pair of adjacent first reaction sub-chambers is separated by the flow guide baffle.

[0017] Optionally, the flue gas co-reaction device further includes a control valve box;

[0018] The control valve box and the denitrification absorbent atomizing nozzle are electrically connected, and the control valve box is used to control the atomization flow rate of the denitrification absorbent atomizing nozzle.

[0019] Optionally, the reaction chamber may further include a plurality of second reaction sub-chambers;

[0020] A second reaction sub-chamber is provided between every two first reaction sub-chambers, and each second reaction sub-chamber is connected to two adjacent first reaction sub-chambers;

[0021] Each of the second reaction chambers is provided with the ion cascade dust collection electrode, the hopper, and the desulfurization absorbent atomizing nozzle, with the hopper and the desulfurization absorbent atomizing nozzle located on both sides of the ion cascade dust collection electrode.

[0022] Optionally, a flexible fabric compensator is provided at the connection between the inlet of the first reaction chamber and the upstream pipeline, and at the connection between the outlet of the first reaction chamber and the downstream pipeline. The flexible fabric compensator is used to absorb thermal expansion.

[0023] Optionally, an economizer is also provided in the upstream pipeline, and the economizer is located between the inertial dust collector and the desulfurization absorbent atomizing nozzle.

[0024] Optionally, the hopper is provided with a sliding guide support at its opening, and the sliding direction of the sliding guide support is consistent with the flow direction of the flue gas in the reaction chamber.

[0025] Optionally, the downstream pipeline also includes an air preheater;

[0026] The air preheater is located at one end of the denitrification catalyst assembly and is used to receive the flue gas discharged from the denitrification catalyst assembly and reduce the temperature of the flue gas.

[0027] Secondly, embodiments of this application also provide a flue gas dust removal, desulfurization, and denitrification control method, wherein the dust removal, desulfurization, and denitrification method is applied to the flue gas co-reaction device described in any one of the first aspects, the flue gas co-reaction device comprising an upstream pipeline, a reaction chamber, and a downstream pipeline, wherein an inertial dust collector and a desulfurization absorbent atomizing nozzle are provided in the upstream pipeline, the reaction chamber comprises a plurality of first reaction sub-chambers, and a denitrification catalyst assembly is provided in the downstream pipeline, characterized in that the method comprises:

[0028] The inertial dust collector installed in the upstream pipeline is controlled to perform pre-dust removal treatment on the flue gas, and the desulfurization absorbent atomizing nozzle installed in the upstream pipeline is controlled to perform desulfurization treatment on the flue gas to generate a first mixed gas;

[0029] The reaction chamber includes multiple first reaction sub-chambers that perform dust removal and denitrification treatment on the first mixed gas to generate a second mixed gas;

[0030] The denitrification catalyst assembly installed in the reaction chamber is controlled to perform denitrification treatment on the second mixed gas to generate a third mixed gas, wherein the third mixed gas is a mixed gas from which particulate matter, sulfur dioxide and nitrogen oxides have been removed.

[0031] Optionally, the method further includes: controlling a plurality of first reaction sub-chambers included in the reaction chamber to perform dust removal and denitrification treatment on the first mixed gas, and controlling a plurality of second reaction sub-chambers to perform semi-dry desulfurization treatment and secondary semi-dry desulfurization treatment on the first mixed gas in sequence to generate a second mixed gas.

[0032] As can be seen from the above embodiments, in this embodiment of the invention, the flue gas co-reaction device includes an upstream pipe, a reaction chamber, and a downstream pipe. The upstream and downstream pipes are located upstream and downstream of the reaction chamber, and the reaction chamber connects the upstream and downstream pipes. An inertial dust collector is installed at the first end of the upstream pipe, and a desulfurization absorbent atomizing nozzle is installed in the upstream pipe. The first end of the upstream pipe is the end of the upstream pipe away from the reaction chamber. The reaction chamber includes multiple first reaction sub-chambers. Each first reaction sub-chamber is equipped with an ion cascade dust collection electrode, a hopper, and a denitrification absorbent atomizing nozzle. The hopper is located at the bottom of the ion cascade dust collection electrode, and the denitrification absorbent atomizing nozzle is located at the top of the ion cascade dust collection electrode. A denitrification catalyst assembly is installed in the downstream pipe. The denitrification catalyst assembly includes multiple denitrification catalyst layers for completing the denitrification reaction. Therefore, on the one hand, sulfur dioxide and particulate matter in the flue gas are removed before it passes through the denitrification catalyst layer, thus reducing the probability of blockage, wear, or poisoning of the catalyst layer by dust and ammonium sulfate, further improving the safety and service life of the device. On the other hand, the flue gas has already undergone pretreatment of larger particulate matter and sulfides before entering the reaction chamber, which can reduce the load on the reaction chamber. Furthermore, since the reaction chamber is equipped with multiple first sub-reaction chambers, multi-stage purification can be achieved through the ion cascade dust collection electrodes set in each first sub-reaction chamber. The resistance to flue gas flow in the ion cascade dust collection electrodes is reduced, thereby ensuring flue gas purification efficiency while reducing the frequency of regular maintenance and replacement, thus lowering the cost of flue gas purification. In summary, the flue gas co-reaction device provided by this invention can treat particulate matter, nitrogen oxides, and sulfur dioxide in flue gas with only one set of equipment, reducing the installation space of the flue gas co-reaction device, saving industrial land, and lowering the cost of flue gas purification. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure of a flue gas co-reaction device provided in an embodiment of this application;

[0034] Figure 2 This is a schematic diagram of another flue gas co-reaction device provided in an embodiment of this application;

[0035] Figure 3 This is a flowchart illustrating the flue gas dust removal, desulfurization, and denitrification control method provided in the embodiments of this application.

[0036] Figure label:

[0037] 1: Upstream pipeline; 2: Reaction chamber; 3: Downstream pipeline; 11: Inertial dust collector; 12: Desulfurization absorbent atomizing nozzle; 13: Economizer; 14: Flexible fabric compensator; 21: First reaction sub-chamber; 22: Second reaction sub-chamber; 31: Denitrification catalyst assembly; 32: Air preheater; 33: Blower; 211: Ion waterfall dust collector; 212: Hopper; 213: Denitrification absorbent atomizing nozzle; 214: Acetylene explosion cleaning assembly; 215: Flow guide baffle; 216: Control valve box; 217: Sliding guide support. Detailed Implementation

[0038] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0039] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of this application. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments.

[0040] Before introducing the flue gas co-reaction device of the present invention, the problems existing in the prior art for removing particulate matter, nitrogen oxides and sulfur dioxide from flue gas and the inventive objectives to be achieved by the embodiments of the present invention are described in detail below:

[0041] The industrial and power sectors typically employ electrostatic precipitators, bag filters, and hybrid electrostatic and bag filters to meet environmental protection requirements for flue gas emissions. These methods are highly efficient at removing larger particles (PM10 and above). However, the non-ferrous metallurgy and power industries require high-temperature dust collectors. Because their operating temperatures range from 300°C to 500°C, this creates favorable conditions for the SCR (Selective Catalytic Reduction) method to remove nitrogen oxides. However, if sulfur trioxide is present in the flue gas, ammonia will react with it to form ammonium sulfate, which can clog the honeycomb SCR catalyst. Therefore, if SCR is used for dust removal, flue gas dust removal and desulfurization must be completed upstream of the process.

[0042] Electrostatic precipitators, in particular, require a large space and demand high levels of manufacturing, installation, and operation expertise, necessitating high manufacturing quality, installation precision, and operational stability. Therefore, their practical application is somewhat limited. While electrostatic precipitators have a wide adaptability to flue gas properties and dust characteristics, they require high precision in the design of operating parameters. Significant deviations from these parameters will alter the performance of the high-temperature electrostatic precipitator.

[0043] To remove nitrogen oxides from flue gas, the SNRB (SOX-NOX-ROXBOX) process can be used for dust removal. This process concentrates the treatment of SO2, NOx, and particulate matter in a high-temperature dust collection chamber. The device may include an economizer, a bag filter, and a heat exchanger. The bag filter is positioned between the economizer and the heat exchanger. A calcium-based absorbent is injected after the economizer to remove sulfur dioxide. An SCR catalyst is suspended in the filter bags of the bag filter, and ammonia is injected before the gas enters the bag filter to remove nitrogen oxides.

[0044] However, when purifying flue gas using the above methods, each stage of denitrification, desulfurization, and dust removal requires independent equipment, occupying significant installation space and industrial land. This results in high requirements for the manufacturing, installation, and operation of flue gas purification systems. Furthermore, the operating temperature during flue gas purification reaches 300℃ to 500℃, necessitating the use of high-temperature resistant ceramic fiber woven filter bags, which require regular maintenance and replacement. Consequently, the cost of flue gas purification is high.

[0045] Based on this, embodiments of the present invention provide a flue gas co-reaction device to achieve the goals of reducing the cost of flue gas purification and reducing industrial construction sites.

[0046] Reference Figure 1 The diagram shows a structural schematic of a flue gas co-reaction device provided in an embodiment of this application. Figure 1As shown, the flue gas co-reaction device includes an upstream pipe 1, a reaction chamber 2, and a downstream pipe 3. The upstream pipe 1 and the downstream pipe 3 are located upstream and downstream of the reaction chamber 2, respectively, and the reaction chamber 2 is connected to the upstream pipe 1 and the downstream pipe 3. An inertial dust collector 3 is installed at the first end of the upstream pipe 1, and a desulfurization absorbent atomizing nozzle 12 is installed in the upstream pipe 1. The first end of the upstream pipe 1 is the end of the upstream pipe 1 away from the reaction chamber 2. The reaction chamber 2 includes multiple first reaction sub-chambers 21. Each first reaction sub-chamber 21 is equipped with an ion cascade dust collection electrode 211, a hopper 212, and a denitrification absorbent atomizing nozzle 213. The hopper 212 is located at the bottom of the ion cascade dust collection electrode 211, and the denitrification absorbent atomizing nozzle 213 is located at the top of the ion cascade dust collection electrode 211. A denitrification catalyst assembly 31 is installed in the downstream pipe 3. The denitrification catalyst assembly 31 includes multiple denitrification catalyst layers for completing the denitrification reaction.

[0047] Among them, the upstream pipe 1, the reaction chamber 2 and the downstream pipe 3 are all cavities with internal cavities. The upstream pipe 1 and the downstream pipe 3 are located upstream and downstream of the reaction chamber 2, respectively. The flue gas to be treated can flow into the reaction chamber 2 from the upstream pipe 1 and then flow into the downstream pipe 3 from the reaction chamber 2.

[0048] The upstream pipe 1 can be a pipe with a bend. An inertial dust collector 3 is installed at the first end of the upstream pipe 1, which is the inlet of the upstream pipe 1, i.e., the end of the upstream pipe 1 away from the reaction chamber 2. The inertial dust collector 3 can be a ceramic multi-tube dust collector or other types of inertial dust collectors 3, and this embodiment of the invention does not limit this. Taking a ceramic multi-tube dust collector as an example, an ash hopper can be connected to the bottom of the ceramic multi-tube dust collector. After the flue gas enters the equipment box through the inlet of the ceramic multi-tube dust collector, larger dust particles will fall directly into the ash hopper through collision, while smaller dust particles will rotate with the flue gas through the ceramic cyclone guide, thereby generating centrifugal force. Through the action of centrifugal force, they are separated from the flue gas and then fall into the ash hopper for storage. In this way, larger particulate matter in the flue gas can be removed by the inertial dust collector 3. The ash collected by the inertial dust collector 3 can be used as an industrial product or sent to cement production for comprehensive utilization, thereby improving the recovery and utilization rate of flue gas.

[0049] In addition, a desulfurization absorbent atomizing nozzle 12 is installed at a suitable temperature location in the upstream pipeline 1. If the upstream pipeline 1 is a bend, the nozzle can be installed at the bend. The desulfurization absorbent can be an amino absorbent or quicklime slurry, which can improve desulfurization efficiency to a certain extent compared to calcium-based absorbents. Of course, calcium-based absorbents can also be used for cost considerations. It should be noted that the desulfurization absorbent atomizing nozzle 12 may include an inner gas pipe axially installed in the outer spray pipe. The inner gas pipe is spirally connected to the outer spray pipe. A nozzle is spirally installed at the end of the outer spray pipe, and an air nozzle is spirally connected at the end of the inner gas pipe. The nozzle has a conical structure with a main spray hole in the middle of the cone. Auxiliary spray holes are located on both sides of the conical surface of the main spray hole. Multiple air holes are evenly distributed on the air nozzle. The desulfurization absorbent is sprayed out from the air holes to remove sulfides in the flue gas. In this way, the larger particulate matter and sulfides in the flue gas are pretreated before entering the reaction chamber, which reduces the load on the reaction chamber and ensures the purification efficiency of the reaction chamber. On the other hand, since sulfur dioxide and particulate matter have been removed before denitrification, the blockage, wear or poisoning of the catalyst layer by soot and ammonium sulfate is reduced. This ensures safety, extends the service life of the equipment, and reduces maintenance costs.

[0050] Optionally, an economizer 13 is also installed in the upstream pipeline 1, which is located between the inertial dust collector 3 and the desulfurization absorbent atomizing nozzle 12.

[0051] It should be noted that by setting an economizer 13 between the inertial dust collector 3 and the desulfurization absorbent atomizing nozzle 12, heat in the high-temperature flue gas can be absorbed, reducing the flue gas exhaust temperature, saving energy, and improving the efficiency of flue gas purification.

[0052] The outlet of the upstream pipe 1 is connected to the reaction chamber 2. The reaction chamber 2 may include multiple first reaction sub-chambers 21. This embodiment of the invention does not limit the number of first reaction sub-chambers 21. Each first reaction sub-chamber 21 is equipped with an ion cascade dust collecting electrode 211, a hopper 212, and a denitrification absorbent atomizing nozzle 213. The hopper 212 and the denitrification absorbent atomizing nozzle 213 are located on both sides of the ion cascade dust collecting electrode 211. The ion cascade dust collecting electrode 211 can be a tubular or honeycomb type. The ion cascade dust collecting electrode 211 can be fixed to the top of the inner cavity of the reaction chamber 2 by steel cables and expands towards the bottom of the cavity. It should be noted that the ion cascade dust collecting electrode 211 can generate a strong ion field, pushing PM10 and smaller fine particulate matter in the flue gas to the collection wall, after which the PM10 and smaller fine particulate matter falls into the hopper 212. Each first reaction sub-chamber 21 corresponds to one hopper 212. After PM10 and smaller fine particulate matter in the flue gas is removed by the ion cascade dust collector 211, the flue gas enters the nitrogen absorbent atomizing nozzle to remove nitrogen oxides. Thus, because the flue gas is purified using the ion cascade dust collector 211, the frequency of regular maintenance and replacement is reduced, lowering the cost of flue gas purification. Furthermore, the reduced resistance to flue gas flow within the ion cascade dust collector 211 helps improve flue gas purification efficiency.

[0053] Optionally, the flue gas co-reaction device also includes an acetylene explosion cleaning component 214; the acetylene explosion cleaning component 214 is located outside the reaction chamber 2, and the acetylene explosion cleaning component 214 is connected to the ion cascade dust collection electrode 211.

[0054] Specifically, the acetylene explosion cleaning component 214 is connected to the ion cascade dust collector 211 through a pipeline. In this way, the explosion impact gas can be distributed to different ion cascade dust collectors 211, realizing the alternating dry cleaning of the ion cascade dust collectors 211 in groups, and further improving the flue gas purification efficiency.

[0055] Optionally, the reaction chamber 2 includes multiple flow guide baffles 215; the flow guide baffles 215 are fixed on the inner wall of the reaction chamber 2, and each two adjacent first reaction sub-chambers 21 are separated by the flow guide baffles 215.

[0056] It should be noted that each guide vane is installed inside the reaction chamber 2 and fixed between two adjacent first reaction sub-chambers 21, thereby separating the two adjacent first reaction sub-chambers 21. Taking a reaction chamber 2 comprising three first reaction sub-chambers 21 as an example, the first reaction sub-chamber 21 connected to the upstream pipe 1 and the middle first reaction sub-chamber 21 are separated by a first guide vane, and the middle first reaction sub-chamber 21 connected to the upstream pipe 1 and the first reaction sub-chamber 21 connected to the exhaust pipe are separated by a second guide vane. In this way, the flue gas sequentially passes through the three first reaction sub-chambers 21 for dust removal and denitrification, so as to achieve multi-stage dust removal and desulfurization and improve the efficiency of dust removal and desulfurization.

[0057] Optionally, the flue gas co-reaction device also includes a control valve box 216; the control valve box 216 is electrically connected to the denitrification absorbent atomizing nozzle 213, and the control valve box 216 is used to control the atomization flow rate of the denitrification absorbent atomizing nozzle 213.

[0058] It should be noted that each set of ion cascade dust collectors 211 is equipped with an independently controlled denitrification absorbent atomizing nozzle 213. Thus, with the control valve box 216 and the denitrification absorbent atomizing nozzle 213 electrically connected, before a certain set of ion cascade dust collectors 211 undergoes explosive cleaning, the atomization flow rate of the denitrification absorbent atomizing nozzle 213 can be increased by controlling the valve box 216 to prevent secondary re-entrainment of accumulated ash. It should also be noted that the atomization flow rate refers to the amount of denitrification absorbent sprayed per unit time.

[0059] Optional, such as Figure 2 As shown, the reaction chamber 2 also includes multiple second reaction sub-chambers 22; a second reaction sub-chamber 22 is provided between every two first reaction sub-chambers 21, and each second reaction sub-chamber 22 connects to two adjacent first reaction sub-chambers 21; each second reaction sub-chamber 22 is provided with an ion cascade dust collection electrode 211, a hopper 212 and a desulfurization absorbent atomizing nozzle 12, and the hopper 212 and the desulfurization absorbent atomizing nozzle 12 are provided on both sides of the ion cascade dust collection electrode 211.

[0060] Specifically, desulfurization is carried out by setting up a desulfurization absorbent atomizing nozzle 12 in the upstream pipeline 1. However, the desulfurization efficiency is limited. Therefore, multiple baffles can be set in the reaction chamber 2 to isolate the reaction chamber 2 into multiple independent sub-chambers, so as to carry out secondary desulfurization at the same time as dust removal and denitrification.

[0061] For example, reaction chamber 2 may include a first chamber, a second chamber, a third chamber, a fourth chamber, and a fifth chamber, wherein the first chamber, the third chamber, and the fifth chamber constitute a first reaction sub-chamber 21, and the second chamber and the fourth chamber constitute a second reaction sub-chamber 22. The inlet of the first chamber is connected to the downstream pipe 3, the outlet of the first chamber is connected to the inlet of the second chamber, the outlet of the second chamber is connected to the inlet of the third chamber, the outlet of the third chamber is connected to the inlet of the fourth chamber, and the outlet of the fourth chamber is connected to the downstream pipe 3.

[0062] The first chamber serves as a dust removal chamber. The dust collected by the hopper 212 in the first chamber can be used for industrial products or comprehensive utilization in cement plants to improve the recovery and utilization rate of flue gas. The second chamber's main function is semi-dry desulfurization. A desulfurization absorbent atomizing nozzle 12, such as a high-speed rotating lime slurry spray nozzle, is installed at the top. The nozzle is made using powder metallurgy to achieve good wear resistance. The atomized lime slurry reacts chemically with sulfur dioxide in the flue gas, and the final product is calcium sulfate, i.e., gypsum, which can be used in building materials. Furthermore, the ionization process at the ion cascade dust collector 211 in the second chamber is beneficial to the desulfurization reaction, further improving desulfurization efficiency. The third chamber can be used for secondary dust removal to collect powdery products such as gypsum formed during desulfurization. The fourth chamber can be used for secondary semi-dry desulfurization to further improve desulfurization efficiency. The fifth chamber can serve as a backup chamber. If further improvement in desulfurization efficiency is needed, it can be used for re-desulfurization; if further improvement in dust removal efficiency is needed, dust removal can be performed again, thus further improving the efficiency of both dust removal and desulfurization.

[0063] Optionally, a flexible fabric compensator 14 is provided at the connection between the inlet of the first reaction chamber 21 and the upstream pipe 1, and at the connection between the outlet of the first reaction chamber 21 and the downstream pipe 3. The flexible fabric compensator 14 is used to absorb thermal expansion.

[0064] It should be noted that since flexible fabric compensators 14 are installed at the connection between the inlet of the first reaction chamber 21 and the upstream pipe 1, and at the connection between the outlet of the first reaction chamber 21 and the downstream pipe 3, thermal expansion can be absorbed, the problem of thermal stress during high-temperature operation can be solved, and the safety performance of the device can be further improved.

[0065] Optionally, the opening of the hopper 212 is provided with a sliding guide support 217, the sliding direction of which is consistent with the flow direction of the flue gas in the reaction chamber 2.

[0066] It should be noted that by fixing the reaction chamber 2 with the sliding guide support 217, the reaction chamber 2 can expand freely in the axial direction, that is, in the direction of flue gas flow, thereby absorbing thermal expansion, solving the problem of thermal stress during high-temperature operation, and further improving the safety performance of the device.

[0067] In addition, a denitrification catalyst assembly 31 is installed in the downstream pipeline 3. The denitrification catalyst assembly 31 is located at the inlet of the downstream pipeline 3. The denitrification catalyst assembly 31 includes multiple denitrification catalyst layers to complete the denitrification reaction. In this way, since sulfur dioxide and particulate matter in the flue gas have been removed before the flue gas passes through the denitrification catalyst layer, the probability of dust and ammonium sulfate clogging, wear or poisoning of the catalyst layer is reduced, further improving the safety and service life of the device.

[0068] Optionally, the downstream pipeline 3 also includes an air preheater 32, which is located at one end of the denitrification catalyst assembly 31 and is used to receive the flue gas discharged from the denitrification catalyst assembly 31 and reduce the temperature of the flue gas.

[0069] It should be noted that since the air preheater is located at one end of the denitrification catalyst assembly 31 and is used to receive the flue gas discharged from the denitrification catalyst assembly 31, the flue gas can avoid low-temperature dew point corrosion after being temperature treated by the air preheater. After passing through the air preheater, the flue gas temperature is lower, reducing exhaust losses and improving the combustion efficiency of industrial equipment.

[0070] It should also be noted that the upstream pipe 1, reaction chamber 2, and downstream pipe 3 can be combined into a U-shaped pipe. To save space in the device layout, other components can be arranged in the space below the reaction chamber 2. For example, a blower 33 can be arranged in the space below the reaction chamber 2. The blower 33 can be connected to the air inlet of the air preheater 32 to supply air to the air preheater 32.

[0071] Furthermore, the embodiments of the present invention can be adapted to different application fields to achieve better implementation results. For example, a circulating fluidized bed boiler can be used with limestone in-furnace desulfurization, thereby further improving desulfurization efficiency. SNCR denitrification can be implemented in the furnace region of the boiler at 800°C to 1100°C, thereby further improving denitrification efficiency. Alternatively, different absorbents, such as solutions, emulsions, or powdered dispersible agents, can be used to allow for absorbent recycling. The embodiments of the present invention do not limit this approach.

[0072] As can be seen from the above embodiments, in this embodiment of the invention, the flue gas co-reaction device includes an upstream pipe 1, a reaction chamber 2, and a downstream pipe 3. The upstream pipe 1 and the downstream pipe 3 are located upstream and downstream of the reaction chamber 2, and the reaction chamber 2 is connected to the upstream pipe 1 and the downstream pipe 3. An inertial dust collector 3 is provided at the first end of the upstream pipe 1, and a desulfurization absorbent atomizing nozzle 12 is provided in the upstream pipe 1. The first end of the upstream pipe 1 is the end of the upstream pipe 1 away from the reaction chamber 2. The reaction chamber 2 includes a plurality of first reaction sub-chambers 21. Each first reaction sub-chamber 21 is provided with an ion cascade dust collection electrode 211, a hopper 212, and a denitrification absorbent atomizing nozzle 213. The hopper 212 is located at the bottom of the ion cascade dust collection electrode 211, and the denitrification absorbent atomizing nozzle 213 is located at the top of the ion cascade dust collection electrode 211. A denitrification catalyst assembly 31 is provided in the downstream pipe 3. The denitrification catalyst assembly 31 is located at the inlet of the downstream pipe 3 and includes multiple denitrification catalyst layers for completing the denitrification reaction. Therefore, on the one hand, sulfur dioxide and particulate matter in the flue gas have been removed before it passes through the denitrification catalyst layer, thus reducing the probability of blockage, wear, or poisoning of the catalyst layer by dust and ammonium sulfate, further improving the safety and service life of the device. On the other hand, the flue gas has already undergone pretreatment of larger particulate matter and sulfides before entering the reaction chamber, which can reduce the load on the reaction chamber. Furthermore, since the reaction chamber is equipped with multiple first sub-reaction chambers 21, multi-stage purification can be achieved through the sub-cascade dust collection electrodes set in each first sub-reaction chamber 21. The resistance to flue gas flow in the ion cascade dust collection electrodes 211 is reduced, thereby ensuring flue gas purification efficiency while reducing the frequency of regular maintenance and replacement, thus lowering the cost of flue gas purification. In summary, the flue gas co-reaction device provided by this embodiment of the invention can treat particulate matter, nitrogen oxides, and sulfur dioxide in flue gas with only one set of equipment, reducing the installation space of the flue gas co-reaction device, saving industrial land, and lowering the cost of flue gas purification.

[0073] In addition, flexible fabric compensators 14 are installed at the connection between the inlet of the first reaction chamber 21 and the upstream pipe 1, and at the connection between the outlet of the first reaction chamber 21 and the downstream pipe 3. Sliding guide supports 217 are installed at the opening of the hopper 212. These designs allow the reaction chamber 2 to expand freely in the axial direction, i.e., in the direction of flue gas flow, thereby absorbing thermal expansion, solving the problem of thermal stress during high-temperature operation, and further improving the safety performance of the device.

[0074] This invention also provides a method for controlling flue gas dust removal, desulfurization, and denitrification. Figure 3This is a flowchart of a flue gas dust removal, desulfurization, and denitrification control method provided in an embodiment of the present invention. The dust removal, desulfurization, and denitrification method described in this coating preparation method is applied to the flue gas synergistic reaction device described in any of the above embodiments. This flue gas synergistic reaction device includes an upstream pipe 1, a reaction chamber 2, and a downstream pipe 3. An inertial dust collector 3 and a desulfurization absorbent atomizing nozzle 12 are installed in the upstream pipe 1. The reaction chamber 2 includes multiple first reaction sub-chambers 21. A denitrification catalyst assembly 31 is installed in the downstream pipe 3. Figure 3 As shown, the method includes:

[0075] Step 101: Control the inertial dust collector 3 installed in the upstream pipeline 1 to perform pre-dust removal treatment on the flue gas, and control the desulfurization absorbent atomizing nozzle 12 installed in the upstream pipeline 1 to perform desulfurization treatment on the flue gas to generate the first mixed gas.

[0076] It should be noted that by controlling the inertial dust collector 3, larger particulate matter in the flue gas can be removed. The ash collected by the inertial dust collector 3 can be used as an industrial product or sent to cement production for comprehensive utilization, thereby improving the recycling rate of flue gas. Sulfur dioxide can be removed from the flue gas by desulfurizing the flue gas through the desulfurizing absorbent atomizing nozzle 12 installed in the upstream pipeline 1. In this way, larger particulate matter and sulfides in the flue gas are pretreated before entering the reaction chamber, reducing the content of larger particulate matter and sulfides in the first mixed gas. Therefore, the load on the reaction chamber can be reduced, ensuring the dust removal efficiency of the reaction chamber.

[0077] Step 102: Control the multiple first reaction sub-chambers 21 included in the reaction chamber 2 to perform dust removal and denitrification treatment on the first mixed gas to generate a second mixed gas.

[0078] It should be noted that the multiple first reaction sub-chambers 21 included in the control reaction chamber 2 perform dust removal and denitrification treatment on the first mixed gas. This pushes PM10 and smaller fine particulate matter in the flue gas onto the collection wall, where it then falls into the hopper 212. Each first reaction sub-chamber 21 corresponds to one hopper 212. After the PM10 and smaller fine particulate matter in the flue gas is removed by the ion cascade dust collector 211, the flue gas enters the nitrification absorbent atomizing nozzle to remove nitrogen oxides. Thus, because the ion cascade dust collector 211 is used for dust removal, the frequency of regular maintenance and replacement is reduced, lowering the cost of flue gas purification. Furthermore, the reduced resistance to flue gas flow within the ion cascade dust collector 211 helps improve the efficiency of flue gas purification.

[0079] To improve desulfurization efficiency, the method may optionally include: controlling multiple first reaction sub-chambers 21 included in the reaction chamber 2 to perform dust removal and denitrification treatment on the first mixed gas, and controlling multiple second reaction sub-chambers 22 to perform semi-dry desulfurization treatment and secondary semi-dry desulfurization treatment on the first mixed gas in sequence to generate a second mixed gas.

[0080] Specifically, desulfurization is carried out by setting up desulfurization absorbent atomizing nozzles 12 in the upstream pipeline 1. However, the desulfurization efficiency is limited. Therefore, multiple baffles can be set in the reaction chamber 2 to isolate the reaction chamber 2 into multiple independent sub-chambers, so as to carry out secondary desulfurization at the same time as dust removal and denitrification.

[0081] For example, reaction chamber 2 may include a first chamber, a second chamber, a third chamber, a fourth chamber, and a fifth chamber, wherein the first chamber, the third chamber, and the fifth chamber constitute a first reaction sub-chamber 21, and the second chamber and the fourth chamber constitute a second reaction sub-chamber 22. The inlet of the first chamber is connected to the downstream pipe 3, the outlet of the first chamber is connected to the inlet of the second chamber, the outlet of the second chamber is connected to the inlet of the third chamber, the outlet of the third chamber is connected to the inlet of the fourth chamber, and the outlet of the fourth chamber is connected to the downstream pipe 3.

[0082] The first chamber serves as a dust removal chamber. The dust collected by the hopper 212 in the first chamber can be used for industrial products or comprehensive utilization in cement plants to improve the recovery and utilization rate of flue gas. The second chamber's main function is semi-dry desulfurization. A desulfurization absorbent atomizing nozzle 12, such as a high-speed rotating lime slurry spray nozzle, is installed at the top. The nozzle is made using powder metallurgy to achieve good wear resistance. The atomized lime slurry reacts chemically with sulfur dioxide in the flue gas, and the final product is calcium sulfate, i.e., gypsum, which can be used in building materials. Furthermore, the ionization process at the ion cascade dust collector 211 in the second chamber is beneficial to the desulfurization reaction, further improving desulfurization efficiency. The third chamber can be used for secondary dust removal to collect powdery products such as gypsum formed during desulfurization. The fourth chamber can be used for secondary semi-dry desulfurization to further improve desulfurization efficiency. The fifth chamber can serve as a backup chamber. If further improvement in desulfurization efficiency is needed, it can be used for re-desulfurization; if further improvement in dust removal efficiency is needed, dust removal can be performed again, thus further improving the efficiency of both dust removal and desulfurization.

[0083] Step 103: Control the denitrification catalyst assembly 31 set in the reaction chamber 2 to complete the denitrification treatment of the second mixed gas and generate a third mixed gas, wherein the third mixed gas is a mixed gas with particulate matter, sulfur dioxide and nitrogen oxides removed.

[0084] A denitrification catalyst assembly 31 is installed in the downstream pipeline 3 at the inlet of the downstream pipeline 3. The denitrification catalyst assembly 31 includes multiple layers of denitrification catalyst to complete the denitrification reaction. In this way, since sulfur dioxide and particulate matter in the flue gas have already been removed when the second mixed gas is treated, the probability of dust and ammonium sulfate clogging, wear, or poisoning of the catalyst layer is reduced, further improving the safety and service life of the device.

[0085] As can be seen from the above embodiments, when removing dust, sulfur dioxide, and nitrogen oxides from flue gas, the inertial dust collector 3 installed in the upstream pipeline 1 is controlled to perform pre-dust removal treatment on the flue gas, and the desulfurization absorbent atomizing nozzle 12 installed in the upstream pipeline 1 is controlled to perform desulfurization treatment on the flue gas, generating a first mixed gas. Then, the multiple first reaction sub-chambers 21 included in the reaction chamber 2 are controlled to perform dust removal and denitrification treatment on the first mixed gas, generating a second mixed gas. Finally, the denitrification catalyst assembly 31 installed in the reaction chamber 2 is controlled to complete the denitrification treatment on the second mixed gas, generating a third mixed gas. The third mixed gas is a mixed gas with particulate matter, sulfur dioxide, and nitrogen oxides removed. In this way, on the one hand, sulfur dioxide and particulate matter in the flue gas are removed before it passes through the denitrification catalyst layer, thus reducing the probability of blockage, wear, or poisoning of the catalyst layer by dust and ammonium sulfate, further improving the safety and service life of the device. On the other hand, the flue gas has already undergone pretreatment of larger particulate matter and sulfides before entering the reaction chamber, which can reduce the load on the reaction chamber. Furthermore, since the reaction chamber is equipped with multiple first sub-reaction chambers 21, multi-stage purification can be achieved through the sub-cascade dust collection electrodes set in each first sub-reaction chamber 21. The resistance to flue gas flow in the ion cascade dust collection electrodes 211 is reduced, thereby ensuring dust removal efficiency while reducing the frequency of regular maintenance and replacement. In summary, the flue gas dust removal, desulfurization, and denitrification method provided by this embodiment of the invention can treat particulate matter, nitrogen oxides, and sulfur dioxide in flue gas with only one set of equipment, reducing the installation space of the flue gas co-reaction device, saving industrial land, and reducing the cost of flue gas purification.

[0086] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0087] Although optional embodiments of the present application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the optional embodiments as well as all changes and modifications falling within the scope of the embodiments of the present application.

[0088] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used merely to distinguish one entity from another, and do not necessarily require or imply any such actual relationship or order between these entities. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or terminal device that includes that element.

[0089] The technical solutions provided in this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the principles and implementation methods of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A flue gas co-reaction device for dust removal, desulfurization, and denitrification of flue gas, characterized in that, The flue gas co-reaction device includes an upstream pipeline, a reaction chamber, and a downstream pipeline; The upstream pipe and the downstream pipe are respectively located upstream and downstream of the reaction chamber, and the reaction chamber is connected to the upstream pipe and the downstream pipe; An inertial dust collector is installed at the first end of the upstream pipeline, and a desulfurization absorbent atomizing nozzle is installed in the upstream pipeline. The first end of the upstream pipeline is the end of the upstream pipeline that is away from the reaction chamber. The reaction chamber includes multiple first reaction sub-chambers. Each first reaction sub-chamber is provided with an ion cascade dust collection electrode, a hopper, and a denitrification absorbent atomizing nozzle. The hopper is located at the bottom of the ion cascade dust collection electrode, and the denitrification absorbent atomizing nozzle is located at the top of the ion cascade dust collection electrode. A denitrification catalyst assembly is installed in the downstream pipeline. The denitrification catalyst assembly is located at the inlet of the downstream pipeline. The denitrification catalyst assembly includes multiple denitrification catalyst layers for completing the denitrification reaction. The flue gas co-reaction device also includes an acetylene explosion cleaning component; the acetylene explosion cleaning component is located outside the reaction chamber and is connected to the ion cascade dust collection electrode; The hopper is provided with a sliding guide support at its opening, and the sliding direction of the sliding guide support is consistent with the flow direction of the flue gas in the reaction chamber.

2. The flue gas co-reaction device according to claim 1, characterized in that, The reaction chamber includes multiple flow guide baffles; The flow guide baffle is fixed on the inner wall of the reaction chamber, and each two adjacent first reaction sub-chambers are separated by the flow guide baffle.

3. The flue gas co-reaction device according to claim 1, characterized in that, The flue gas co-reaction device also includes a control valve box; The control valve box and the denitrification absorbent atomizing nozzle are electrically connected, and the control valve box is used to control the atomization flow rate of the denitrification absorbent atomizing nozzle.

4. The flue gas co-reaction device according to claim 1, characterized in that, The reaction chamber also includes multiple second reaction sub-chambers; A second reaction sub-chamber is provided between every two first reaction sub-chambers, and each second reaction sub-chamber is connected to two adjacent first reaction sub-chambers; Each of the second reaction chambers is provided with the ion cascade dust collection electrode, the hopper, and the desulfurization absorbent atomizing nozzle, with the hopper and the desulfurization absorbent atomizing nozzle located on both sides of the ion cascade dust collection electrode.

5. The flue gas co-reaction device according to claim 1, characterized in that, Flexible fabric compensators are provided at the connection between the inlet of the first reaction chamber and the upstream pipeline, and at the connection between the outlet of the first reaction chamber and the downstream pipeline. The flexible fabric compensators are used to absorb thermal expansion.

6. The flue gas co-reaction device according to claim 1, characterized in that, An economizer is also installed in the upstream pipeline, and the economizer is located between the inertial dust collector and the desulfurization absorbent atomizing nozzle.

7. The flue gas co-reaction device according to claim 1, characterized in that, The downstream pipeline also includes an air preheater; The air preheater is located at one end of the denitrification catalyst assembly and is used to receive the flue gas discharged from the denitrification catalyst assembly and reduce the temperature of the flue gas.

8. A method for controlling flue gas dust removal, desulfurization, and denitrification, wherein the method is applied to the flue gas co-reaction device according to any one of claims 1-7, the flue gas co-reaction device comprising an upstream pipeline, a reaction chamber, and a downstream pipeline, wherein an inertial dust collector and a desulfurization absorbent atomizing nozzle are provided in the upstream pipeline, the reaction chamber comprises a plurality of first reaction sub-chambers, and a denitrification catalyst assembly is provided in the downstream pipeline, characterized in that, The method includes: The inertial dust collector installed in the upstream pipeline is controlled to perform pre-dust removal treatment on the flue gas, and the desulfurization absorbent atomizing nozzle installed in the upstream pipeline is controlled to perform desulfurization treatment on the flue gas to generate a first mixed gas; The reaction chamber includes multiple first reaction sub-chambers that perform dust removal and denitrification treatment on the first mixed gas to generate a second mixed gas; The denitrification catalyst assembly installed in the reaction chamber is controlled to perform denitrification treatment on the second mixed gas to generate a third mixed gas, wherein the third mixed gas is a mixed gas from which particulate matter, sulfur dioxide and nitrogen oxides have been removed.

9. The flue gas dust removal, desulfurization, and denitrification control method according to claim 8, wherein the reaction chamber comprises a plurality of second reaction sub-chambers, characterized in that, The method further includes: The reaction chamber is controlled to perform dust removal and denitrification treatment on the first mixed gas by multiple first reaction sub-chambers, and the reaction chamber is controlled to perform semi-dry desulfurization treatment and secondary semi-dry desulfurization treatment on the first mixed gas in sequence to generate a second mixed gas.

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