Low-carbon sintering flue gas circulation system and purification process for multi-pollutant collaborative treatment

Abstract

The invention relates to the technical field of energy conservation and carbon reduction in metallurgy, and provides a low-carbon sintering flue gas circulation system and purification process for multi-pollutant collaborative treatment, the low-carbon sintering flue gas circulation system and purification process are used for staged treatment of sintering flue gas, and the low-carbon sintering flue gas circulation system comprises a sintering chamber which is provided with a sintering cavity and a flue gas blowing port; the sintering cavity leads to the high-sulfur air duct or the low-sulfur air duct, and the low-sulfur air duct leads to the flue gas blowing port; and the high-sulfur air duct leads to the first flue gas treatment system. By means of the technical scheme, the problem that in the prior art, energy consumption for treating flue gas generated after sintering of sintering ore is high is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of metallurgical energy conservation and carbon reduction, and in particular to a low-carbon sintering flue gas circulation system and a purification process for coordinated treatment of multiple pollutants. Background Art

[0002] In the industrial field involving sintering of sintered ore, such as steel production, a large amount of sulfur-containing waste gas is generated after the sintering process is completed. Traditional flue gas treatment technology faces many problems when dealing with such sintering flue gas, the most prominent of which is the problem of excessive energy consumption.

[0003] In the past, sintering flue gas was not carefully classified and treated, but a unified treatment method was adopted. All sulfur-containing flue gas was treated equally and required to go through a complex and energy-intensive treatment process, which made the operating cost of the entire flue gas treatment system high.

[0004] With increasingly stringent environmental protection requirements, the emission restrictions on various pollutants in sintering flue gas have become increasingly strict, which has further aggravated the difficulties of traditional processes. Not only does it require more energy to remove pollutants, but the treatment effect is often unsatisfactory, and it is difficult to simultaneously meet the low emission requirements of pollutants such as sulfur oxides, nitrogen oxides and dust. Summary of the invention

[0005] The present invention proposes a low-carbon sintering flue gas circulation system and purification process for coordinated treatment of multiple pollutants, which solves the problem of high energy consumption in the related art for treating the flue gas generated after sintering of sintered ore.

[0006] The technical solution of the present invention is as follows: The low-carbon sintering flue gas circulation system with multi-pollutant coordinated treatment is used to grade the sintering flue gas, including: A sintering chamber, wherein the sintering chamber has a sintering cavity and a flue gas injection port; A high-sulfur air duct and a low-sulfur air duct, the sintering chamber leads to the high-sulfur air duct and the low-sulfur air duct, and the low-sulfur air duct leads to the flue gas injection port; The first flue gas treatment system, the high-sulfur air duct leads to the first flue gas treatment system.

[0007] Optionally, it also includes: a second flue gas treatment system, wherein the low-sulfur air duct is connected to the flue gas injection port via the second flue gas treatment system, wherein the second flue gas treatment system comprises a first fan, a first electrostatic precipitator and a dehydrator, wherein the first fan, the first electrostatic precipitator and the dehydrator are connected in sequence; The first flue gas treatment system comprises a second fan, a second electrostatic precipitator, a first desulfurization device, an annular cooler, a bag filter and a denitration device, wherein the second fan, the second electrostatic precipitator, the first desulfurization device, the annular cooler, the bag filter and the denitration device are connected in sequence. Optionally, it further comprises an emission device, the first flue gas treatment system leads to the emission device, and further comprises: a first regulating valve, located between the first electrostatic precipitator and the dehydrator, the first electrostatic precipitator leads to the dehydrator through the first regulating valve, the first regulating valve also leads to the discharge device, and the first regulating valve is used to adjust the flow rate of the low-sulfur flue gas entering the dehydrator; The second desulfurization device is arranged on the low-sulfur air duct and is located between the first regulating valve and the emission device, and is used for desulfurizing the excess low-sulfur flue gas discharged by the first regulating valve.

[0008] Optionally, the ring cooler has a low temperature part and a high temperature part, the low temperature part is arranged between the first desulfurization device and the bag filter, and the high temperature part is arranged in parallel with the low temperature part, and further comprises: a second regulating valve, the second regulating valve being connected in series with the high temperature portion and being located between the first desulfurization device and the high temperature portion; A heat exchanger is connected in series with the high temperature part and is located between the high temperature part and the bag filter.

[0009] Optionally, the bag filter comprises: A shell, the shell having an air inlet and an air outlet, the air inlet being connected to the heat exchanger, the air outlet being connected to the denitration device, and the shell having a maintenance port; A mounting plate, the mounting plate being rotatably disposed in the shell, the mounting plate dividing the interior of the shell into a first cavity and a second cavity, the air inlet being connected to the first cavity, the air outlet and the maintenance port being connected to the second cavity, the mounting plate having a plurality of mounting holes, and after the mounting plate is rotated, the plurality of mounting holes are sequentially moved circumferentially to below the maintenance port; A filter bag, wherein the filter bag is provided in a plurality of quantities and the filter bag is arranged in the installation hole, and the gas to be processed passes through the filter bag from the first cavity into the second cavity.

[0010] Optionally, the bag filter further comprises: A knocking rod, one end of which is swingably disposed on the inner wall of the first cavity; A resetting elastic member, two ends of which act on the knocking rod and the inner wall of the first cavity respectively, so as to provide a force for the other end of the knocking rod to approach the axis of the mounting plate; After the mounting plate rotates, the other end of the knocking rod knocks a plurality of the filter bags in sequence.

[0011] Optionally, the plurality of filter cloth bags have different lengths, and the lengths of the plurality of filter cloth bags decrease gradually along the axis of the mounting plate. There are a number of knocking rods, which are arranged longitudinally, and the knocking rods from top to bottom knock on the filter bags from short to long in sequence.

[0012] Optionally, the bag filter further comprises: A cover plate, the cover plate is rotatably disposed on the shell, and the cover plate is used to close the maintenance opening after being rotated; A rotating shaft, the rotating shaft is rotatably disposed in the second cavity, one end of the rotating shaft is connected to the mounting plate, and the other end extends out of the second cavity; A driving member, wherein the driving member is arranged on the housing, and an output end of the driving member is connected to the rotating shaft for driving the mounting plate to rotate.

[0013] Optionally, the cover plate has a through hole, and the rotating shaft passes through the through hole; The inner wall of the through hole has a plurality of clamping grooves, the plurality of clamping grooves are evenly distributed around the circumference of the axis of the rotating shaft, and a transition surface is provided at the connection between the clamping groove and the inner wall of the through hole, and the transition surface is a curved surface; The rotating shaft has a sliding groove; The top of the shell has a first limiting column and a second limiting column. After the cover plate abuts against the first limiting column, the cover plate closes the maintenance port. After the cover plate abuts against the second limiting column, the cover plate opens the maintenance port. The bag dust collector also includes: A sliding driving rod, wherein the sliding driving rod is slidably disposed in the sliding groove; The second elastic member is arranged in the slide slot, and two ends of the second elastic member act on the sliding driving rod and the slide slot respectively, so as to provide a force for the sliding driving rod to approach the clamping slot.

[0014] The low-carbon sintering flue gas purification process for coordinated control of multiple pollutants uses a low-carbon sintering flue gas circulation system for coordinated control of multiple pollutants.

[0015] The working principle and beneficial effects of the present invention are: In the present invention, sulfur-containing waste gas is generated in the sintering process, and part of the sulfur-containing waste gas can be reused. The purpose of this system is to recycle flue gas with a SO2 concentration below 50 mg / m³. The principle is that flue gas with a sulfur content below 50 mg / m³ will not significantly increase the sulfur content of the sintered ore, and the product quality of the sintered ore can be guaranteed. Flue gas is divided into high-sulfur flue gas and low-sulfur flue gas, wherein flue gas with a SO2 concentration below 50 mg / m³ is defined as low-sulfur flue gas, and flue gas with a sulfur content of more than 50 mg / m³ is high-sulfur flue gas. This classification management enables different types of flue gas to be reasonably handled, thereby reducing the impact on the quality of sintered ore products. For low-sulfur flue gas, it is smoothly transported to the flue gas injection port through reasonable bend and flow rate control design, so that the low-sulfur flue gas is coupled with the injection air, which significantly increases the wind temperature and can effectively reduce solid fuel consumption. At the same time, the high-sulfur flue gas flows into the desulfurization system. After wet desulfurization, due to the low flue gas temperature, it needs to be preheated in advance. We pass the high-sulfur flue gas (after desulfurization) into the high-temperature section of the ring cooler, and use the temperature of the sintered ore to raise the flue gas temperature again to achieve effective preheating. During the preheating process, CO in the flue gas reacts with calcium ferrite in the sintered ore to catalyze NO X The reduction of CO and CO is synergistic, preparing for the subsequent SCR denitrification process. Although this process reduces the waste heat power generation of the ring cooler, it reduces the SCR heating energy consumption and the required NO removal. X The total amount and overall energy consumption of the system are significantly reduced. Through the above optimization design, the present invention not only improves the energy efficiency of the sintering process, but also effectively reduces environmental pollution, with significant economic and ecological benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The preferred implementation modes will be described below in a clear and understandable manner with reference to the accompanying drawings to further illustrate the above-mentioned characteristics, technical features, advantages and implementation methods of the present invention.

[0017] Figure 1 It is a schematic diagram of the structural flow of the present invention; Figure 2 It is a schematic diagram of the structure of the bag dust collector of the present invention; Figure 3 It is a schematic diagram of the internal structure of the bag filter of the present invention; Figure 4 For the present invention Figure 3 Enlarged view of point A in the middle; Figure 5 This is a schematic diagram of the internal structure of the bag dust collector of the present invention from another angle; Figure 6 For the present invention Figure 5 Enlarged view of point B in the middle; Figure 7 For the present invention Figure 2 Enlarged view of point C in the middle; Figure 8 For the present invention Figure 7 Enlarged view of point D in the middle.

[0018] In the figure: 1, sintering chamber, 2, high sulfur air duct, 3, low sulfur air duct, 101, sintering chamber, 102, flue gas blowing port, 4, discharge device, 301, first fan, 302, first electrostatic precipitator, 303, dehydrator, 201, second electrostatic precipitator, 202, first desulfurization device, 203, ring cooler, 204, bag filter, 205, denitrification device, 304, first regulating valve, 305, second desulfurization device, 2031, low temperature part, 2032, high temperature part, 206, second regulating valve, 207, heat exchanger, 208, second fan, 5 , shell, 501, air inlet, 502, air outlet, 503, maintenance port, 6, mounting plate, 504, first cavity, 505, second cavity, 601, mounting hole, 7, filter bag, 801, knocking rod, 802, reset elastic member, 9, cover plate, 10, rotating shaft, 11, driving member, 901, through hole, 902, snap-in groove, 903, transition surface, 1001, slide groove, 507, first limiting column, 506, second limiting column, 12, sliding drive rod, 13, first area, 14, second area, 15, third area, 16, fourth area. DETAILED DESCRIPTION In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0019] In order to simplify the drawings, only the parts related to the invention are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically shown, or only one of them is marked. In this article, "one" not only means "only one", but also means "more than one", and "several" includes "two" and "more than two".

[0020] In this document, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0021] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0022] Reference Figure 1 to Figure 8 , which is the first embodiment of the present invention, proposes a low-carbon sintering flue gas circulation system for coordinated control of multiple pollutants, which is used for graded treatment of sintering flue gas, including a sintering chamber 1, the sintering chamber 1 has a sintering cavity 101 and a flue gas injection port 102; a high-sulfur air duct 2 and a low-sulfur air duct 3, the sintering cavity 101 leads to the high-sulfur air duct 2 and the low-sulfur air duct 3, the low-sulfur air duct 3 leads to the flue gas injection port 102; a first flue gas treatment system, the high-sulfur air duct 2 leads to the first flue gas treatment system.

[0023] In this embodiment, in order to solve the problem of high energy consumption for treating flue gas generated after sintering of sintered ore in related technologies. The sintering chamber 1 is made of alloy steel material that is resistant to high temperatures and has good chemical stability, and its internal sintering cavity 101 is a rectangular structure. Sulfur-containing waste gas will be generated during the sintering process, and some of the sulfur-containing waste gas can be reused. The purpose of this system is to recycle flue gas with a SO2 concentration below 50 mg / m³. Therefore, flue gas with a SO2 concentration below 50 mg / m³ is defined as low-sulfur flue gas, and vice versa as high-sulfur flue gas. This data can be changed accordingly according to process requirements.

[0024] Multiple flue gas injection ports 102 are evenly arranged on the top of the sintering chamber 101 to ensure smooth exhaust of flue gas. High-precision SO2 concentration sensors are installed at key positions of the air duct to accurately monitor the SO2 concentration of flue gas in real time based on advanced optical detection technology.

[0025] During the combustion of sintered ore, the sintered ore will continue to move in the sintering chamber 1 and will continue to generate sulfur-containing waste gas. When the sintered ore just enters the sintering chamber 101, the sulfur content of the waste gas generated by sintering is higher than 50 mg / m³. This is the first area 13, and the first area 13 is connected to the high-sulfur air duct 2. As the sintered ore gradually moves, the sulfur content in the generated flue gas is less than 50 mg / m 3 This is the second area 14, which is connected to the low-sulfur air duct 3. As the sintering time increases, the reaction becomes increasingly intense, and the sulfur content in the generated exhaust gas is higher than 50 mg / m 3 This area is the third area 15, and the third area 15 is connected to the high-sulfur air duct 2; when the sintered ore moves to the discharge port, the reaction has been basically completed, and the sulfur content in the sintering exhaust gas is lower than 50 mg / m 3 This is the fourth area 16 , and the fourth area 16 is connected to the low-sulfur air duct 3 .

[0026] Concentration less than 50 mg / m 3The low-sulfur flue gas is smoothly transported to the flue gas injection port 102 through the low-sulfur air duct 3 by using reasonable bend and flow rate control design, and coupled with the injected air to increase the injection temperature; the high-sulfur flue gas is first wet desulfurized and then preheated in the first and second stages of the ring cooler. During the preheating process, CO and NO in the sintered ore are X This process not only reduces the total amount of SCR denitrification but also avoids the flue gas heating step before denitrification. While saving the cost of low-sulfur flue gas treatment, by precisely controlling parameters such as sintering temperature, time and atmosphere, the catalytic active components such as calcium ferrite in the sintered ore are fully activated during the formation process, ensuring that these natural catalysts play the best role in the subsequent synergistic removal of carbon monoxide and nitrogen oxides.

[0027] The advantage is that the flue gas is divided into high-sulfur flue gas and low-sulfur flue gas, where the flue gas with SO2 concentration below 50mg / m³ is defined as low-sulfur flue gas, and the flue gas above 50mg / m³ is high-sulfur flue gas. This classification management enables different types of flue gas to be handled reasonably, thereby reducing the impact on the quality of sintered ore products. For low-sulfur flue gas, through reasonable bend and flow rate control design, it is smoothly transported to the flue gas injection port, so that the low-sulfur flue gas is coupled with the injection air, which significantly increases the wind temperature and can effectively reduce solid fuel consumption. At the same time, the high-sulfur flue gas flows into the desulfurization system. After wet desulfurization, the flue gas temperature is relatively low, so it needs to be preheated in advance. We pass the high-sulfur flue gas (after desulfurization) into the high-temperature section of the ring cooler, and use the temperature of the sintered ore to raise the flue gas temperature again to achieve effective preheating. During the preheating process, the CO in the flue gas reacts with the calcium ferrite in the sintered ore to catalyze the NO X The reduction of CO and CO is synergistic, preparing for the subsequent SCR denitrification process. Although this process reduces the waste heat power generation of the ring cooler, it reduces the SCR heating energy consumption and the required NO removal. X The total amount and overall energy consumption of the system are significantly reduced. Through the above optimization design, the present invention not only improves the energy efficiency of the sintering process, but also effectively reduces environmental pollution, with significant economic and ecological benefits.

[0028] Furthermore, it also includes a second flue gas treatment system, the low-sulfur air duct 3 is connected to the flue gas injection port 102 through the second flue gas treatment system, the second flue gas treatment system includes a first fan 301, a first electrostatic precipitator 302 and a dehydrator 303, and the first fan 301, the first electrostatic precipitator 302 and the dehydrator 303 are connected in sequence; the first flue gas treatment system includes a second fan 208, a second electrostatic precipitator 201, a first desulfurization device 202, a ring cooler 203, a bag filter 204 and a denitrification device 205, and the second fan 208, the second electrostatic precipitator 201, the first desulfurization device 202, the ring cooler 203, the bag filter 204 and the denitrification device 205 are connected in sequence, In this embodiment, in the second flue gas treatment system, the first fan 301 uses a high-efficiency centrifugal fan, whose impeller is specially treated for wear resistance and corrosion resistance, and is connected to the low-sulfur air duct 3 to ensure stable extraction of low-sulfur flue gas. The first electrostatic precipitator 302 uses an advanced plate-type electrostatic precipitator, and the plate spacing is optimized to efficiently adsorb dust particles in low-sulfur flue gas. The dehydrator 303 uses a cyclone dehydrator 303, which is internally provided with spiral guide blades and a separation structure to effectively separate the water in the flue gas under the action of centrifugal force. In the first flue gas treatment system, the second fan 208 uses a high-power axial flow fan to provide power for high-sulfur flue gas. The second electrostatic precipitator 201 uses tubular electrostatic precipitator technology, and the pipe diameter and pipe length are designed according to the flue gas flow rate and dust characteristics to enhance the dust removal effect. The first desulfurization device 202 adopts a mature limestone-gypsum wet desulfurization process, and the desulfurization tower is filled with a high-activity desulfurizer, and is equipped with a spray and stirring system to ensure sufficient desulfurization. The ring cooler 203 adopts a multi-stage structure, and the cooling capacity and temperature control of each stage are precise. Its low temperature section 2031 and high temperature section 2032 are closely connected with the upstream and downstream equipment through independent high temperature resistant pipes. During the cooling process, the catalytic active components such as calcium ferrite on the surface of the sintered ore are used to create favorable conditions for the synergistic removal of carbon monoxide and nitrogen oxides. The bag filter 204 uses high-quality high temperature resistant and corrosion resistant filter bag 7 materials. The filter area is reasonably designed according to the flue gas treatment volume to ensure a good filtering effect. The denitrification device 205 adopts efficient selective catalytic reduction (SCR) technology, is loaded with high-performance vanadium titanium catalysts, and guarantees the denitrification efficiency through precise temperature and flow control.

[0029] The advantage is that the treatment systems constructed for low-sulfur and high-sulfur flue gases are highly adapted to their respective flue gas characteristics. The second flue gas treatment system effectively purifies low-sulfur flue gas to ensure its subsequent utilization or emission compliance; the first flue gas treatment system comprehensively treats high-sulfur flue gas, and all links work closely together, especially the ring cooler 203 uses the catalytic properties of sintered ore to promote the coordinated removal of pollutants, significantly improving the removal efficiency of the entire system for multiple pollutants. At the same time, the optimized selection and design of each equipment improves the reliability and stability of the system and reduces equipment failure rate and maintenance costs.

[0030] Furthermore, it also includes an emission device 4. The first flue gas treatment system leads to the emission device 4. It also includes a first regulating valve 304, which is located between the first electrostatic precipitator 302 and the dehydrator 303. The first electrostatic precipitator 302 leads to the dehydrator 303 through the first regulating valve 304. The first regulating valve 304 also leads to the emission device 4. The first regulating valve 304 is used to adjust the flow rate of the low-sulfur flue gas entering the dehydrator 303; a second desulfurization device 305. The second desulfurization device 305 is arranged on the low-sulfur air duct 3, between the first regulating valve 304 and the emission device 4, and is used to desulfurize the excess low-sulfur flue gas discharged from the first regulating valve 304.

[0031] In this embodiment, the discharge device 4 adopts a chimney with suitable height and solid structure, and multiple layers of high-efficiency anti-corrosion coating are applied inside to ensure long-term resistance to flue gas corrosion. Advanced flue gas flow sensors and high-sensitivity pollutant concentration analyzers are accurately installed at the bottom, which can monitor various key indicators of flue gas in real time and accurately. The first regulating valve 304 uses an electric regulating valve with high-precision control capability, and its electric actuator responds quickly and operates stably, and is seamlessly connected with the bottom monitoring instrument through a reliable automatic control system. During the operation of the system, when the low-sulfur flue gas from the first electrostatic precipitator 302 enters this link, the flow sensor and concentration analyzer continuously monitor the flue gas state and transmit the data to the control system in real time. If the flue gas flow or composition fluctuates abnormally, the control system quickly drives the first regulating valve 304 to operate according to the preset logic program. If the flue gas flow exceeds the processing capacity of the dehydrator 303, the first regulating valve 304 will smoothly guide the excess low-sulfur flue gas to the second desulfurization device 305 according to the precise adjustment strategy; if the flue gas composition does not meet the standard for entering the dehydrator 303, the flow direction will be adjusted in time. The second desulfurization device 305 adopts an efficient spray drying desulfurization process. A specially designed high-speed rotating atomizing nozzle is installed inside the desulfurization tower, which can evenly disperse the desulfurizer into tiny droplets, fully mix and contact with the flue gas, and ensure the efficient desulfurization reaction. Its processing capacity has been strictly designed to cope with the possible excess low-sulfur flue gas. In the whole process, the natural catalytic activity of the sintered ore is fully utilized to further enhance the synergistic removal effect of carbon monoxide and nitrogen oxides, and optimize the overall purification efficiency of the system.

[0032] The benefit is that the first regulating valve 304 plays a key hub role in the entire flue gas treatment process. By accurately controlling the flow of low-sulfur flue gas entering the dehydrator 303, it is ensured that the dehydrator 303 always operates under the best working conditions, effectively avoiding problems such as equipment blockage, corrosion or poor treatment effect caused by excessive flow or abnormal composition, significantly improving the working efficiency and service life of the dehydrator 303, and reducing equipment maintenance costs. At the same time, the excess low-sulfur flue gas is reasonably directed to the second desulfurization device 305 for secondary treatment to ensure that all low-sulfur flue gas can be properly treated, greatly reducing the emission of untreated or incompletely treated flue gas, reducing the risk of environmental pollution, and improving the environmental performance and reliability of the system.

[0033] Furthermore, the annular cooler 203 has a low-temperature part 2031 and a high-temperature part 2032, the low-temperature part 2031 is arranged between the first desulfurization device 202 and the bag-type dust collector 204, and the high-temperature part 2032 is arranged in parallel with the low-temperature part 2031, and also includes a second regulating valve 206, the second regulating valve 206 is connected in series with the high-temperature part 2032, and is located between the first desulfurization device 202 and the high-temperature part 2032; the heat exchanger 207 is connected in series with the high-temperature part 2032, and is located between the high-temperature part 2032 and the bag-type dust collector 204.

[0034] In this embodiment, the ring cooler 203 adopts a segmented design, which is divided into a low temperature part 2031 and a high temperature part 2032. The second regulating valve 206 uses a highly sensitive pneumatic regulating valve, which monitors data feedback in real time through accurate pressure sensors and temperature sensors, and accurately adjusts the flue gas flow entering the high temperature part 2032. The heat exchanger 207 adopts an efficient plate structure, and reasonable guide grooves are designed between the plates to ensure that the flue gas and the cooling medium are fully in contact and heat exchange during the flow process.

[0035] When the system is started, the high-sulfur flue gas extracted by the second fan 208 contains a large amount of impurities and heat energy and is transported to the second electrostatic precipitator 201. The flue gas after dedusting enters the first desulfurization device 202 for wet desulfurization, which greatly reduces the sulfur content of the flue gas. At the same time, this process is accompanied by the dissipation of heat, and the flue gas temperature also drops significantly.

[0036] Subsequently, the high-sulfur flue gas with a lowered temperature enters the high-temperature section 2032 of the ring cooler 203. When the flue gas flushes the sintered ore in the high-temperature section 2032 to cool the sintered ore, the temperature of the flue gas itself rises again due to the principle of heat exchange. The high-sulfur flue gas with a raised temperature does not need to be heated again during denitration, creating a suitable temperature condition for the denitration reaction, enabling the denitration catalyst to fully exert its activity, and undergoing a series of complex and efficient chemical reactions with nitrogen oxides in the flue gas, converting harmful nitrogen oxides into harmless nitrogen and water, completing the flue gas denitration process.

[0037] The advantage is that high-sulfur flue gas flows into the desulfurization system. After wet desulfurization, the flue gas temperature is relatively low, so it needs to be preheated in advance. We pass the high-sulfur flue gas (after desulfurization) into the high-temperature section of the ring cooler, and use the temperature of the sintered ore to raise the flue gas temperature again to achieve effective preheating. During the preheating process, CO in the flue gas reacts with calcium ferrite in the sintered ore to catalyze NO X The reduction of CO and CO is synergistic, preparing for the subsequent SCR denitrification process. Although this process reduces the waste heat power generation of the ring cooler, it reduces the SCR heating energy consumption and the required NO removal. XThe total amount and overall energy consumption of the system are significantly reduced. Through the above optimization design, the present invention not only improves the energy efficiency of the sintering process, but also effectively reduces environmental pollution, with significant economic and ecological benefits.

[0038] Furthermore, the bag filter 204 includes a shell 5, which has an air inlet 501 and an air outlet 502. The air inlet 501 is connected to the heat exchanger 207, and the air outlet 502 is connected to the denitrification device 205. The shell 5 has a maintenance port 503; the mounting plate 6 is rotatably arranged in the shell 5, and the mounting plate 6 divides the interior of the shell 5 into a first cavity 504 and a second cavity 505. The air inlet 501 is connected to the first cavity 504, and the air outlet 502 and the maintenance port 503 are both connected to the second cavity 505. The mounting plate 6 has a plurality of mounting holes 601. After the mounting plate 6 rotates, the plurality of mounting holes 601 move circumferentially in sequence to below the maintenance port 503; there are a plurality of filter bags 7, and the filter bags 7 are arranged in the mounting holes 601. The gas to be treated enters the second cavity 505 from the first cavity 504 through the filter bags 7.

[0039] In this embodiment, the shell 5 of the bag filter 204 is made of carbon steel with moderate thickness, and has reinforcing ribs welded inside to enhance the overall strength. The positions and sizes of the air inlet 501 and the air outlet 502 are precisely designed to ensure that the smoke can flow in and out smoothly and evenly distributed. The maintenance port 503 is set in a position that is convenient for operation, and the size is sufficient for personnel to carry out maintenance. The mounting plate 6 is made of a lightweight and sturdy aluminum alloy material, and is installed in the shell 5 through a central axis and a high-precision bearing to ensure that it can rotate flexibly. There are multiple mounting holes 601 evenly distributed on the mounting plate 6, and their diameters are closely matched with the size of the filter bag 7 to ensure that the filter bag 7 is firmly installed and well sealed. The filter bag 7 is made of high-quality polytetrafluoroethylene fiber material, which has excellent high temperature resistance, corrosion resistance and filtering performance. It is customized according to the specifications of the mounting hole 601 and is tightly installed in the mounting hole 601.

[0040] An advanced dust concentration monitoring device is installed in the air outlet 502 of the bag filter 204. The device adopts the principle of laser scattering and can accurately detect the dust concentration in the exhaust flue gas in real time. At the same time, a pressure sensor is installed in the first cavity 504 to monitor the pressure change of the flue gas when it passes through the filter bag 7. When the filter bag 7 is damaged, the dust concentration in the flue gas will rise sharply, or the pressure change will fluctuate abnormally. Once the monitoring data exceeds the preset normal range, the control system will immediately issue an alarm.

[0041] At the same time, a micro radio frequency identification tag (RFID) is installed on the top of each filter bag 7, and each tag has a unique code. A group of radio frequency readers are set in the first cavity 504, and when the device is running, the radio frequency reader continuously scans each tag. Once the dust concentration or pressure abnormality in a certain area is detected, the damaged filter bag 7 can be quickly located by comparing the radio frequency identification tag code corresponding to the area.

[0042] When individual filter bags 7 are found to be damaged in the above manner, the driving device will start to drive the mounting plate 6 to rotate. The mounting plate 6 rotates smoothly around the central axis. As the mounting plate 6 rotates, the mounting hole 601 with the damaged bag will gradually move to the bottom of the maintenance port 503, and be accurately positioned, so that the maintenance personnel can quickly perform replacement operations.

[0043] The advantage is that by real-time monitoring of dust concentration and pressure changes, and combining radio frequency identification technology to accurately locate damaged bags, the damage of the filter bags 7 can be discovered and dealt with in a timely manner, avoiding large amounts of dust emissions due to filtration failure. The design of being able to move the bag below the maintenance port 503 by rotating the mounting plate 6 after the bag is found to be damaged greatly optimizes the maintenance process. Compared with the traditional method of removing the entire outer shell to find and replace damaged bags, this design saves a lot of maintenance time, improves equipment availability, and reduces production interruptions caused by maintenance.

[0044] Furthermore, the bag dust collector 204 also includes a knocking rod 801, one end of which is swingably set on the inner wall of the first cavity 504; the two ends of the reset elastic member 802 act on the knocking rod 801 and the inner wall of the first cavity 504 respectively, for providing a force for the other end of the knocking rod 801 to approach the axis of the mounting plate 6; after the mounting plate 6 rotates, the other end of the knocking rod 801 knocks on several filter bags 7 in turn.

[0045] In this embodiment, one end of the knocking rod 801 is swingably connected to the inner wall of the first cavity 504 through a high-strength steel shaft. The reset elastic member 802 uses a spiral spring with stable performance. The two ends of the spring are tightly fixed at specific positions of the knocking rod 801 and the inner wall of the first cavity 504. During the operation of the equipment, when the mounting plate 6 rotates, the mounting hole 601 drives the filter bag 7 to move in an orderly manner. At this time, the knocking rod 801 will abut against several filter bags 7 in turn, and under the elastic force of the reset elastic member 802, the knocking rod 801 can accurately knock each filter bag 7 in turn.

[0046] The advantage is that the combination design of the knocking rod 801 and the reset elastic member 802 provides an efficient automatic dust cleaning function for the filter bag 7. When a filter bag 7 is damaged, the remaining filter bags 7 can be cleaned while being repaired, effectively preventing excessive accumulation of dust on the bag surface, and avoiding problems such as a sharp increase in filtration resistance and a significant decrease in filtration efficiency due to dust accumulation. This not only maintains the stable operation of the bag filter 204 and ensures a good filtration effect, but also significantly reduces the workload and cost of manual dust cleaning.

[0047] Furthermore, the lengths of the filter bags 7 are different, and the lengths of the filter bags 7 decrease along the axis of the mounting plate 6; there are a number of knocking rods 801, and the knocking rods 801 are arranged longitudinally, and the knocking rods 801 from top to bottom knock on the filter bags 7 from short to long in turn.

[0048] In this embodiment, the length of the filter bag 7 is designed to decrease along the axis of the mounting plate 6. The shortest filter bag 7 is located at the outermost side. The length is optimized and determined according to the actual flue gas flow distribution and dust settling law. The longest filter bag 7 is located at the center. The number and longitudinal arrangement of the knocking rods 801 match the filter bag 7, and the length is customized according to the corresponding position of the filter bag 7. During the cleaning process, as the mounting plate 6 rotates at a uniform speed, filter bags 7 of different lengths pass through the corresponding knocking rods 801 in turn. It is possible to apply knocking force to filter bags 7 of different lengths, so that the dust attached to the surface of the bag can be fully removed.

[0049] The advantage is that the differentiated length design of the filter bag 7 and the layout of the knocking rod 801 adapted thereto greatly optimize the cleaning effect. This avoids the problem of incomplete or excessive cleaning of some bags that may be caused by the traditional unified cleaning method. This improves the overall performance and stability of the bag filter 204, effectively reduces the energy consumption of the equipment operation, and further reduces the equipment maintenance cost.

[0050] Furthermore, the bag dust collector 204 also includes a cover plate 9, which is rotatably set on the shell 5, and is used to close the maintenance port 503 after rotation; the rotating shaft 10 is rotatably set in the second cavity 505, one end of the rotating shaft 10 is connected to the mounting plate 6, and the other end extends out of the second cavity 505; the driving member 11 is set on the shell 5, and the output end of the driving member 11 is connected to the rotating shaft 10, which is used to drive the mounting plate 6 to rotate.

[0051] In this embodiment, the cover plate 9 is rotatably connected to the top of the housing 5, and the cover plate 9 is rotated to open or close the maintenance port 503. The drive member 11 uses a reduction motor with appropriate power and accurately adjustable speed. It is installed at a specific position on the housing 5 and is tightly connected to the rotating shaft 10 through a high-strength coupling. When the equipment needs maintenance, the operator starts the drive member 11 through the control system, and the output shaft of the drive member 11 drives the rotating shaft 10 to rotate slowly, so that the mounting plate 6 rotates at a predetermined speed and direction. The mounting plate 6 moves the filter bag 7 that needs maintenance to the position below the maintenance port 503.

[0052] Furthermore, the cover plate 9 has a through hole 901, and the shaft 10 passes through the through hole 901; the inner wall of the through hole 901 has a plurality of snap-in grooves 902, and the plurality of snap-in grooves 902 are evenly distributed around the axis of the shaft 10, and the connection between the snap-in groove 902 and the inner wall of the through hole 901 has a transition surface 903, and the transition surface 903 is an arc surface; the shaft 10 has a slide groove 1001; the top of the housing 5 has a first limiting column 507 and a second limiting column 506, and the cover plate 9 and the first limiting column 507 and the second limiting column 506 are connected. 07 After abutment, the cover plate 9 closes the maintenance port 503. After the cover plate 9 abuts against the second limiting column 506, the cover plate 9 opens the maintenance port 503. The bag dust collector 204 also includes a sliding drive rod 12, which is slidably set in the slide groove 1001; the second elastic member is set in the slide groove 1001, and the two ends of the second elastic member act on the sliding drive rod 12 and the slide groove 1001 respectively, so as to provide a force for the sliding drive rod 12 to approach the clamping groove 902.

[0053] In this embodiment, the cover plate 9 rotates horizontally on the top of the shell 5, and the maintenance port 503 is opened or closed after the rotation. One end of the rotating shaft 10 is connected to the output shaft of the driving member 11 through a coupling, and the other end accurately passes through the through hole 901 of the cover plate 9 and keeps rotating in the second cavity 505. On the inner wall of the through hole 901 of the cover plate 9, a plurality of snap-in grooves 902 are evenly distributed, and the arc surface between these snap-in grooves 902 and the inner wall of the through hole 901 serves as a transition surface 903. A slide groove 1001 adapted to the sliding drive rod 12 is correspondingly provided on the rotating shaft 10, and the sliding drive rod 12 is accurately placed in the slide groove 1001. The second elastic member adopts a disc spring with stable performance, which is installed in the slide groove 1001, and continuously provides a stable thrust to the sliding drive rod 12 in the direction of the snap-in groove 902, ensuring that the sliding drive rod 12 is tightly matched with the snap-in groove 902.

[0054] When the system detects that a filter bag 7 needs to be repaired, the driving member 11 starts to operate and drives the rotating shaft 10 to start rotating. Since the sliding driving rod 12 is tightly abutted against the clamping groove 902 under the action of the second elastic member, the rotation of the rotating shaft 10 can effectively drive the cover plate 9 to rotate synchronously. As the rotation continues, when one side edge of the cover plate 9 abuts against the second limiting column 506, the cover plate 9 stops rotating. While the rotating shaft 10 still keeps rotating, one end of the sliding driving rod 12 will follow the guidance of the transition surface 903, overcome the elastic force of the second elastic member, and smoothly slide out of the current clamping groove 902, and quickly enter the next clamping groove 902 under the push of the second elastic member. Since the position of the cover plate 9 has been restricted by the second limiting column 506 and cannot continue to rotate, the rotating shaft 10 will idle relative to the cover plate 9 in the through hole 901. During this period, the mounting plate 6 continues to rotate driven by the rotating shaft 10, and the mounting hole 601 with the damaged filter bag 7 is accurately moved to the position directly below the maintenance port 503, providing a convenient operating space for the maintenance personnel. After the maintenance work is completed, the driving member 11 rotates in the opposite direction, and the rotating shaft 10 drives the cover plate 9 to rotate horizontally in the opposite direction. When the cover plate 9 abuts against the first limit column 507, it indicates that the cover plate 9 has completely closed the maintenance port 503. At this time, the sliding driving rod 12 will be accurately inserted into the corresponding clamping groove 902 again to ensure that the cover plate 9 is fixed, so that the equipment returns to normal operation.

[0055] The low-carbon sintering flue gas purification process for coordinated control of multiple pollutants uses a low-carbon sintering flue gas circulation system for coordinated control of multiple pollutants.

[0056] By setting high-sulfur and low-sulfur air ducts 3, the flue gas generated by the sintering chamber 1 is classified using a high-precision SO2 concentration sensor based on electrochemical detection technology. When the SO2 concentration in the flue gas is lower than 50mg / m 3 When the concentration of sulfur flue gas exceeds 300, the low-sulfur flue gas is transported to the injection port through the low-sulfur air duct 3; and the high-sulfur flue gas with a concentration higher than this enters the subsequent treatment process. The low-sulfur flue gas is drawn into the second flue gas treatment system by the centrifugal first fan 301 with a specially treated impeller, first enters the plate-type first electrostatic precipitator 302 with an optimized plate design for dust removal, and then enters the cyclone dehydrator 303 with a special structure. In this process, the intelligent electric first regulating valve 304 accurately controls the flue gas flow entering the dehydrator 303 based on the data fed back by the monitor that uses ultrasonic flow measurement and spectral analysis of concentration in the discharge device 4, and the excess is transported to the spray-drying second desulfurization device 305 equipped with a high-efficiency nozzle and good airflow distribution for re-desulfurization.

[0057] Deep treatment and synergistic reaction of high-sulfur flue gas. The high-sulfur flue gas enters the first flue gas treatment system under the suction action of the high-power axial flow second fan 208 that can adjust the wind pressure. It first passes through the tubular second electrostatic precipitator 201 with optimized pipe diameter and pipe length to remove dust, and then enters the first desulfurization device 202 that adopts the limestone-gypsum wet method, has a highly active desulfurizer and an advanced spray stirring system for desulfurization. The desulfurized flue gas enters the ring cooler 203 with a multi-stage design and excellent cooling pipe performance, and removes carbon monoxide and nitrogen oxides with the help of the catalytic components on the surface of the sintered ore. In this process, the pneumatic second regulating valve 206, which is equipped with high-precision pressure and temperature sensors and has a sensitive response, accurately adjusts the amount of flue gas entering the high-temperature part 2032 of the ring cooler 203 according to the temperature and pressure changes in the system. At the same time, the plate-type heat exchanger 207 with high-quality heat exchange plates and guide grooves recovers the heat of the high-temperature flue gas for preheating other media or process links, and cools the flue gas before transporting it to the bag filter 204, and then to the denitrification device 205, and finally discharged from the emission device 4.

[0058] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A low-carbon sintering flue gas circulation system for coordinated treatment of multiple pollutants, used for graded treatment of sintering flue gas, characterized in that: include: A sintering chamber (1), wherein the sintering chamber (1) comprises a sintering cavity (101) and a flue gas injection port (102); A high-sulfur air duct (2) and a low-sulfur air duct (3), the sintering chamber (101) leads to the high-sulfur air duct (2) and the low-sulfur air duct (3), and the low-sulfur air duct (3) leads to the flue gas injection port (102); A first flue gas treatment system, wherein the high-sulfur air duct (2) leads to the first flue gas treatment system.

2. The low-carbon sintering flue gas circulation system for coordinated control of multiple pollutants according to claim 1 is characterized in that: Also includes: a second flue gas treatment system, wherein the low-sulfur air duct (3) is connected to the flue gas injection port (102) via the second flue gas treatment system, the second flue gas treatment system comprises a first fan (301), a first electrostatic precipitator (302) and a dehydrator (303), and the first fan (301), the first electrostatic precipitator (302) and the dehydrator (303) are connected in sequence; The first flue gas treatment system comprises a second fan (208), a second electrostatic precipitator (201), a first desulfurization device (202), a ring cooler (203), a bag filter (204) and a denitrification device (205); the second fan (208), the second electrostatic precipitator (201), the first desulfurization device (202), the ring cooler (203), the bag filter (204) and the denitrification device (205) are connected in sequence.

3. The low-carbon sintering flue gas circulation system for coordinated control of multiple pollutants according to claim 2 is characterized in that: It also includes an exhaust device (4), the first flue gas treatment system leads to the exhaust device (4), and further includes: a first regulating valve (304) located between the first electrostatic precipitator (302) and the dehydrator (303); the first electrostatic precipitator (302) leads to the dehydrator (303) via the first regulating valve (304); the first regulating valve (304) also leads to the discharge device (4); the first regulating valve (304) is used to regulate the flow rate of the low-sulfur flue gas entering the dehydrator (303); A second desulfurization device (305), the second desulfurization device (305) is arranged on the low-sulfur air duct (3), located between the first regulating valve (304) and the discharge device (4), and is used for desulfurizing the excess low-sulfur flue gas discharged by the first regulating valve (304).

4. The low-carbon sintering flue gas circulation system for coordinated multi-pollutant treatment according to claim 2 is characterized in that: The ring cooler (203) comprises a low temperature part (2031) and a high temperature part (2032), the low temperature part (2031) being arranged between the first desulfurization device (202) and the bag filter (204), the high temperature part (2032) being arranged in parallel with the low temperature part (2031), and further comprising: a second regulating valve (206), the second regulating valve (206) being connected in series with the high-temperature portion (2032) and being located between the first desulfurization device (202) and the high-temperature portion (2032); A heat exchanger (207), wherein the heat exchanger (207) is connected in series with the high-temperature portion (2032) and is located between the high-temperature portion (2032) and the bag filter (204).

5. The low-carbon sintering flue gas circulation system for coordinated control of multiple pollutants according to claim 4 is characterized in that: The bag filter (204) comprises: A shell (5), the shell (5) having an air inlet (501) and an air outlet (502), the air inlet (501) being connected to the heat exchanger (207), the air outlet (502) being connected to the denitration device (205), and the shell (5) having a maintenance port (503); a mounting plate (6), the mounting plate (6) being rotatably disposed in the shell (5), the mounting plate (6) dividing the interior of the shell (5) into a first cavity (504) and a second cavity (505), the air inlet (501) being connected to the first cavity (504), the air outlet (502) and the maintenance port (503) both being connected to the second cavity (505), the mounting plate (6) having a plurality of mounting holes (601), and after the mounting plate (6) is rotated, the plurality of mounting holes (601) are sequentially moved in a circumferential direction to below the maintenance port (503); A filter bag (7), wherein the filter bags (7) are provided in a plurality, the filter bags (7) being arranged in the mounting hole (601), and the gas to be treated passes from the first cavity (504) through the filter bags (7) into the second cavity (505).

6. The low-carbon sintering flue gas circulation system for coordinated control of multiple pollutants according to claim 5 is characterized in that: The bag filter (204) further comprises: A knocking rod (801), one end of which is swingably disposed on the inner wall of the first cavity (504); a resetting elastic member (802), wherein two ends of the resetting elastic member (802) act on the knocking rod (801) and the inner wall of the first cavity (504) respectively, and are used to provide a force for the other end of the knocking rod (801) to approach the axis of the mounting plate (6); After the mounting plate (6) rotates, the other end of the knocking rod (801) knocks on a plurality of the filter bags (7) in sequence.

7. The low-carbon sintering flue gas circulation system for coordinated control of multiple pollutants according to claim 6 is characterized in that: The plurality of filter bags (7) have different lengths, and the lengths of the plurality of filter bags (7) decrease gradually along the axis of the mounting plate (6); There are a plurality of knocking rods (801), and the knocking rods (801) are arranged longitudinally, and the knocking rods (801) from top to bottom knock the filter bags (7) from short to long in sequence.

8. The low-carbon sintering flue gas circulation system for coordinated control of multiple pollutants according to claim 5 is characterized in that: The bag filter (204) further comprises: a cover plate (9), the cover plate (9) being rotatably disposed on the housing (5), and the cover plate (9) being used to close the maintenance opening (503) after being rotated; a rotating shaft (10), the rotating shaft (10) being rotatably disposed in the second cavity (505), one end of the rotating shaft (10) being connected to the mounting plate (6), and the other end extending out of the second cavity (505); A driving member (11), the driving member (11) being arranged on the housing (5), the output end of the driving member (11) being connected to the rotating shaft (10) and being used for driving the mounting plate (6) to rotate.

9. The low-carbon sintering flue gas circulation system for coordinated control of multiple pollutants according to claim 8 is characterized in that: The cover plate (9) has a through hole (901), and the rotating shaft (10) passes through the through hole (901); The inner wall of the through hole (901) has a plurality of snap-fit ​​grooves (902), the plurality of snap-fit ​​grooves (902) are evenly distributed around the axis of the rotating shaft (10), and a transition surface (903) is provided at the connection between the snap-fit ​​grooves (902) and the inner wall of the through hole (901), and the transition surface (903) is a curved surface; The rotating shaft (10) has a sliding groove (1001); The top of the shell (5) has a first limiting column (507) and a second limiting column (506); after the cover plate (9) abuts against the first limiting column (507), the cover plate (9) closes the maintenance opening (503); after the cover plate (9) abuts against the second limiting column (506), the cover plate (9) opens the maintenance opening (503); the bag dust collector (204) further comprises: A sliding driving rod (12), wherein the sliding driving rod (12) is slidably disposed in the sliding groove (1001); A second elastic member, wherein the second elastic member is arranged in the slide groove (1001), and two ends of the second elastic member act on the sliding driving rod (12) and the slide groove (1001) respectively, so as to provide a force for the sliding driving rod (12) to approach the clamping groove (902).

10. A low-carbon sintering flue gas purification process for coordinated multi-pollutant control, using a low-carbon sintering flue gas circulation system for coordinated multi-pollutant control as claimed in any one of claims 1 to 9, characterized in that: S1. Low-sulfur flue gas treatment: The low-sulfur flue gas is drawn into the second flue gas treatment system by the first fan (301), and is sequentially passed through the first electrostatic precipitator (302) for dust removal and the dehydrator (303) for dehydration. During this process, the first regulating valve (304) controls the flue gas flow entering the dehydrator (303) according to monitoring data, and the excess part is sent to the second desulfurization device (305) for desulfurization, and then discharged from the discharge device (4); S2. High-sulfur flue gas treatment: The high-sulfur flue gas is drawn into the first flue gas treatment system through the second fan (208); the flue gas is first dedusted by the second electrostatic precipitator (201), and then enters the first desulfurization device (202) for desulfurization; the flue gas after desulfurization enters the multi-stage ring cooler (203), during which the second regulating valve (206) regulates the amount of flue gas entering the high-temperature part (2032) of the ring cooler (203); the flue gas is finally filtered by the bag filter (204) and denitrated by the denitrification device (205), and then discharged from the emission device (4).

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