A sintering machine head flue bag dust removal system and method

Abstract

The application discloses a sintering machine head flue gas bag type dust removal system and method, which comprises a bag type dust remover, a dust removal pretreatment device, a first pipeline unit and a second pipeline unit. The first discharge port of the dust removal pretreatment device is communicated with the bag type dust remover through the first pipeline unit, and the second discharge port of the dust removal pretreatment device is communicated with the bag type dust remover through the second pipeline unit. The second pipeline unit comprises a bypass pipeline, a spark extinguishing device and an alkalinity adjusting device which are arranged in sequence and communicated. The dust removal pretreatment device comprises a primary spark monitor, an air inlet pipeline and a dust removal frame body with a hollow cavity. The sintering machine head flue gas bag type dust removal system and method solve the technical problem of unstable operation of the existing sintering machine head flue gas bag type dust removal system.

Description

Technical Field

[0001] This invention relates to the field of sintering machine technology, and in particular, to a bag-type dust collection system and method for sintering machine head flue gas. Background Technology

[0002] Sintering is a fundamental step in the steel industry, providing high-quality raw materials for ironmaking. The sintering process involves batching, mixing, granulating, and then feeding the iron-containing raw materials onto a sintering trolley. Finally, during the uniform operation of the sintering machine, the materials are roasted at high temperatures (≤1400℃) by the action of ventilation, causing a series of physicochemical changes in the materials. After crushing, the materials are transformed into porous, blocky sintered ore with a certain strength.

[0003] Sintering, as a major process in ironmaking, accounts for 20% of the total pollutant emissions from the steel industry. Sintering machine flue gas is characterized by large volume, high temperature, high corrosiveness, easy condensation, high negative pressure, and fluctuating operating conditions, making it difficult to treat. Traditionally, electrostatic precipitators (ESPs) have been used for flue gas purification both domestically and internationally. However, due to their unstable dust removal efficiency, the outlet particulate matter concentration exceeds the standard (ranging from 50 mg / m³ to 150 mg / m³), seriously affecting the stable compliance of subsequent desulfurization and denitrification systems. This has become a bottleneck problem restricting ultra-low emissions from the sintering process and urgently needs to be solved. Baghouse filters can efficiently remove fine particulate matter, with an outlet particulate matter concentration of <10 mg / m³. Using baghouse filters to purify sintering machine flue gas can achieve stable ultra-low emissions.

[0004] Based on baghouse dust collection for flue gas treatment, how to ensure the stable operation of the baghouse dust collection system for sintering machine head flue gas is a technical problem that urgently needs to be solved. Summary of the Invention

[0005] The sintering machine head flue gas bag filter dust collection system and method provided by the present invention solves the technical problem of unstable operation of existing sintering machine head flue gas bag filter dust collection systems, and solves the problem that the filter bags are easily burned through by sparks in the flue gas when using bag filters for purification in sintering machine heads.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A baghouse dust collection system for sintering machine head flue gas includes a baghouse dust collector, a dust pretreatment device, a first piping unit, and a second piping unit. The first discharge port of the dust pretreatment device is connected to the baghouse dust collector via the first piping unit, and the second discharge port of the dust pretreatment device is connected to the baghouse dust collector via the second piping unit. The second piping unit includes a bypass pipe, a spark extinguishing device, and an alkalinity adjustment device arranged sequentially and connected to each other. The dust pretreatment device includes a primary spark detector, an inlet pipe, and a dust collection frame with a hollow cavity. The dust collector frame has an initial flue gas inlet, a first discharge port, and a second discharge port that are connected to the hollow cavity. An inlet pipe is located at the initial flue gas inlet and is connected to the hollow cavity. A primary spark detector is located on the inlet pipe. The first discharge port is connected to the bag filter through a first pipeline unit, and the second discharge port is connected to the bag filter through a second pipeline unit. The first pipeline unit is equipped with a first control valve for controlling the on / off state of the first pipeline unit, and the second pipeline unit is equipped with a second control valve for controlling the on / off state of the second pipeline unit.

[0008] Furthermore, the dust collector frame includes a rotating cone, a rotating drive mechanism, a dust collector filter hood, a dust collection trough, and a dust collector cylinder with a hollow cavity. The top surface of the dust collector cylinder is provided with a first discharge port, and the side walls of the dust collector cylinder are respectively provided with an initial flue gas inlet and a second discharge port. The second discharge port is located above the initial flue gas inlet. A mounting frame is provided at the bottom opening of the dust collector cylinder. The dust collector filter hood is covered by the rotating cone, and the dust collector cylinder is covered by the rotating cone. A discharge gap is left between the dust collector filter hood and the inner wall of the dust collector cylinder. The rotating drive mechanism is mounted on the mounting frame. The rotating cone is arranged vertically with its large-diameter end facing the rotating drive mechanism. A spiral guide groove is recessed on the outer circumference of the rotating cone. The dust collection trough is located at the bottom of the dust collector cylinder. The air inlet pipe passes through the initial flue gas inlet and the side wall of the dust collector filter hood and is arranged towards the rotating cone.

[0009] Furthermore, fire extinguishing protrusions are provided on the outer circumferential wall of the rotating cone, and the fire extinguishing protrusions are staggered with the spiral guide groove.

[0010] Furthermore, the dust removal pretreatment device also includes a primary temperature detector installed on the air inlet pipe, and the sintering machine head flue gas bag dust removal system also includes a heating device and a cooling device. The heating device includes a hot air duct for communicating with the hollow cavity, and a hot air control valve for controlling the opening and closing of the hot air duct is provided on the hot air duct. The cooling device includes a cold air duct for communicating with the hollow cavity, and a cold air control valve for controlling the opening and closing of the cold air duct is provided on the cold air duct.

[0011] Furthermore, the second piping unit also includes a secondary spark monitor, a bypass pipe for connecting the second discharge port and the spark extinguishing device, an alkalinity adjustment device for connecting the spark extinguishing device and the bag filter, and the secondary spark monitor is located on the bypass pipe.

[0012] Furthermore, the spark extinguishing device includes a fire extinguishing cylinder, a fire extinguishing fluid spraying mechanism, and a fire extinguishing gas spraying mechanism. The fire extinguishing cylinder is arranged horizontally, with the air inlet at the axial end of the fire extinguishing cylinder connected to the output end of a bypass pipe, and the air outlet at the axial end of the fire extinguishing cylinder connected to the input port of an alkalinity regulating device. The fire extinguishing fluid spraying mechanism and the fire extinguishing gas spraying mechanism are arranged at intervals along the axial direction of the fire extinguishing cylinder. The fire extinguishing fluid spraying mechanism is used to spray atomized fluid into the fire extinguishing cylinder, and the fire extinguishing gas spraying mechanism is used to spray fire extinguishing gas into the fire extinguishing cylinder.

[0013] Furthermore, the fire extinguishing fluid spraying mechanism includes a storage tank, a liquid booster pump, a liquid supply pipe, and a spraying plate. The spraying plate is located inside the fire extinguishing cylinder and is coaxially arranged with the fire extinguishing cylinder. Spraying holes are provided on the circumferential wall surface of the spraying plate. The storage tank is located outside the fire extinguishing cylinder and is connected to the spraying plate through the liquid supply pipe. The liquid booster pump is located on the liquid supply pipe. And / or the fire extinguishing gas spraying mechanism includes a gas storage tank, a gas booster pump, a gas supply pipe, and a spraying plate. The spraying plate is located inside the fire extinguishing cylinder and is coaxially arranged with the fire extinguishing cylinder. Spraying holes are provided on the circumferential wall surface of the spraying plate. The gas storage tank is located outside the fire extinguishing cylinder and is connected to the spraying plate through the gas supply pipe. The gas booster pump is located on the gas supply pipe.

[0014] Furthermore, an acidity detector is installed inside the bypass pipe. The alkalinity adjustment device includes an alkalinity adjustment cylinder, an ash collection box, and an alkaline ash spraying mechanism. The alkalinity adjustment cylinder is arranged vertically. A bottom smoke inlet is provided on the bottom side wall of the alkalinity adjustment cylinder, and a top smoke outlet is provided on the top side wall of the alkalinity adjustment cylinder. The ash collection box is located at the bottom ash outlet of the alkalinity adjustment cylinder. The bottom smoke inlet is connected to the spark extinguishing device through a secondary connecting pipe. The alkaline ash spraying mechanism includes an alkaline ash spraying pipe arranged radially along the alkalinity adjustment cylinder. The alkaline ash spraying pipe is located at the top of the alkalinity adjustment cylinder and below the top smoke outlet. An alkaline ash spraying head is provided on the bottom surface of the alkaline ash spraying pipe facing the bottom ash outlet.

[0015] Furthermore, the alkalinity adjustment device also includes a reflection mechanism, which includes a first reflection plate arranged horizontally and a second reflection plate arranged at an angle. The first reflection plate is located between the ash spray head and the top smoke outlet. The first reflection plate has a first air hole that penetrates the first reflection plate vertically. The second reflection plate is inclined at the inlet position of the top smoke outlet to allow the flue gas to enter the top smoke outlet after filtration. The air inlet side of the second reflection plate is inclined downward vertically, and the second reflection plate has a second air hole that penetrates the second reflection plate.

[0016] This invention also provides a baghouse dust collection method for sintering machine head flue gas, used in the aforementioned baghouse dust collection system for sintering machine head flue gas, comprising the following steps: acquiring temperature data of the flue gas entering the dust collection frame through the inlet pipe using a primary temperature sensor; if the temperature data is greater than a preset temperature threshold, injecting low-temperature flue gas into the dust collection frame through a cold air duct; if the temperature data is less than the preset temperature threshold, injecting high-temperature flue gas into the dust collection frame through a hot air duct; acquiring spark data of the flue gas entering the dust collection frame through the inlet pipe using a primary spark detector; if the spark data is within a preset spark threshold range, connecting the dust collection pretreatment device to the baghouse dust collector through a first pipeline unit, forming... The first flue gas emission treatment path; if the spark data is not within the preset spark threshold range, the dust removal pretreatment device is connected to the bag filter through the second pipeline unit to form the second flue gas emission treatment path; the spark parameters of the flue gas entering the spark extinguishing device through the bypass pipe are obtained through the secondary spark monitor. If the spark parameters are not within the preset parameter threshold range, the spark extinguishing device is activated to spray extinguishing fluid and / or extinguishing gas into the flue gas flowing through the spark extinguishing device. The acidity information of the flue gas entering the alkalinity adjustment device is obtained. If the acidity information is less than the preset acidity threshold, the alkalinity adjustment device is activated to spray alkaline ash into the flue gas flowing through the alkalinity adjustment device and guide the flue gas to the bag filter.

[0017] The present invention has the following beneficial effects:

[0018] The sintering machine head flue gas bag filter dust collection system of the present invention includes a bag filter, a dust pretreatment device, a first pipeline unit, and a second pipeline unit. The bag filter treats the sintering machine head flue gas, achieving stable ultra-low emissions. The dust pretreatment device and the first pipeline unit work together to form a first flue gas treatment and emission path, and the dust pretreatment device and the second pipeline unit work together to form a second flue gas treatment and emission path. The dust pretreatment device includes a primary spark detector, an inlet pipe, and a dust collection frame with a hollow cavity. The dust collection frame has an initial flue gas inlet, a first emission outlet, and a second emission outlet communicating with the hollow cavity. The primary spark detector is located on the inlet pipe. During the process of introducing the flue gas from the machine head into the hollow cavity through the intake pipe, the spark data entering the hollow cavity is monitored by a primary spark detector. If the spark data is greater than the preset spark threshold, the flue gas from the machine head is controlled to enter the bag filter through the second pipeline unit. If the spark data is not greater than the preset spark threshold, the flue gas from the machine head is controlled to enter the bag filter through the first pipeline unit. When the spark data is greater than the preset spark threshold, the flue gas from the machine head passes through the spark extinguishing device and the alkalinity adjustment device before entering the bag filter. This solves the problem that the filter bags are easily burned through due to the presence of sparks in the flue gas from the machine head when using a bag filter for dust removal, and solves the technical problem of unstable operation of the existing sintering machine head flue gas bag filter system.

[0019] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0020] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0021] Figure 1 This is one of the structural schematic diagrams of a bag filter system for sintering machine head flue gas in one embodiment of the present invention;

[0022] Figure 2 This is a second schematic diagram of the structure of the sintering machine head flue gas bag dust removal system in one embodiment of the present invention;

[0023] Figure 3 yes Figure 1 A schematic diagram of the dust removal pretreatment device in the middle;

[0024] Figure 4 yes Figure 1 A partial structural diagram of the heating device in the diagram;

[0025] Figure 5 yes Figure 1 A schematic diagram of the spark extinguishing device in the image;

[0026] Figure 6 yes Figure 5 A schematic diagram of the fire extinguishing fluid spraying mechanism in the system;

[0027] Figure 7 yes Figure 6 A schematic diagram of the fire extinguishing gas injection mechanism in the image;

[0028] Figure 8 yes Figure 1 A schematic diagram of the alkalinity adjustment device in the image.

[0029] Explanation of icon numbers:

[0030] 100. Sintering machine head flue gas bag filter system; 10. Bag filter; 20. Dust pretreatment device; 21. Primary spark detector; 22. Inlet duct; 23. Dust collector frame; 231. Rotating cone; 2311. Spiral guide channel; 232. Rotary drive mechanism; 233. Dust collector filter hood; 234. Ash collection trough; 235. Dust collector cylinder; 236. Fire extinguishing protrusion; 237. Primary temperature detector; 30. First piping unit; 40. Second piping unit. 41. Bypass pipe; 42. Spark extinguishing device; 421. Fire extinguishing cylinder; 422. Fire extinguishing fluid spraying mechanism; 423. Fire extinguishing gas spraying mechanism; 43. Alkalinity adjusting device; 431. Alkalinity adjusting cylinder; 432. Ash collection box; 433. Alkali ash spraying mechanism; 434. Reflection mechanism; 44. Secondary spark detector; 45. Acidity detector; 50. Heating device; 51. Hot air duct; 52. Combustion mechanism; 60. Cooling device. Detailed Implementation

[0031] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0033] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0034] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0035] In the existing sintering machine head flue gas bag filter system, the flue gas in the sintering machine's air box is collected into the main flue by the action of the exhaust fan, and then passes through the bag filter for dust removal, the flue gas desulfurization device for desulfurization, and the flue gas denitrification device for denitrification before being discharged through the chimney.

[0036] Research revealed the following technical problems with existing baghouse dust collection systems for sintering machine head flue gas: First, when using belt dust collectors for dust collection in existing sintering flue gas systems, the filter bags are easily burned through by sparks in the flue gas, resulting in poor stability. Second, existing baghouse dust collectors for sintering flue gas are easily affected by temperature fluctuations in the sintering flue gas, leading to low dust collection efficiency and a high failure rate. Specifically, if the sintering flue gas temperature is too high, the filter bags in the baghouse dust collector are easily burned through; if the sintering flue gas temperature is too low, acidic gases in the flue gas are prone to condensation and corrosion of the filter bags. Third, the filter bags in existing baghouse dust collectors for sintering flue gas are easily worn by large particles of dust in the flue gas (especially high-hardness, large-particle iron ore powder, return ore particles, etc.), resulting in a short service life.

[0037] like Figure 1 and Figure 2 As shown, the present invention provides a baghouse dust collection system 100 for sintering machine head flue gas, including a baghouse dust collector 10, a dust pretreatment device 20, a first pipeline unit 30, and a second pipeline unit 40. The first discharge port of the dust pretreatment device 20 is connected to the baghouse dust collector 10 through the first pipeline unit 30, and the second discharge port of the dust pretreatment device 20 is connected to the baghouse dust collector 10 through the second pipeline unit 40. The second pipeline unit 40 includes a bypass pipe 41, a spark extinguishing device 42, and an alkalinity adjusting device 43 arranged and connected in sequence. The dust pretreatment device 20 includes a primary spark detector 21, an air inlet pipe 22, and a hollow... The dust collector frame 23 has an initial flue gas inlet, a first discharge port, and a second discharge port that communicate with the hollow cavity. The air inlet pipe 22 is located at the initial flue gas inlet and communicates with the hollow cavity. The primary spark detector 21 is located on the air inlet pipe 22. The first discharge port is connected to the bag filter 10 through the first pipeline unit 30, and the second discharge port is connected to the bag filter 10 through the second pipeline unit 40. The first pipeline unit is provided with a first control valve for controlling the on / off state of the first pipeline unit, and the second pipeline unit is provided with a second control valve for controlling the on / off state of the second pipeline unit.

[0038] The sintering machine head flue gas bag filter system 100 provided by the present invention includes a bag filter 10, a dust pretreatment device 20, a first pipeline unit 30, and a second pipeline unit 40. The bag filter 10 treats the sintering machine head flue gas, achieving stable ultra-low emissions. The dust pretreatment device 20 and the first pipeline unit 30 cooperate to form a first flue gas treatment and emission path, and the dust pretreatment device 20 and the second pipeline unit 40 cooperate to form a second flue gas treatment and emission path. The dust pretreatment device 20 includes a primary spark detector 21, an air inlet pipe 22, and a dust collection frame 23 with a hollow cavity. The dust collection frame 23 has an initial flue gas inlet, a first emission outlet, and a second emission outlet communicating with the hollow cavity. The primary spark detector 21 is located at the... On the inlet pipe 22, during the process of introducing the machine head flue gas into the hollow cavity through the inlet pipe 22, the primary spark detector 21 monitors the spark data entering the hollow cavity. If the spark data is greater than the preset spark threshold, the machine head flue gas is controlled to enter the bag filter 10 through the second pipeline unit 40. If the spark data is not greater than the preset spark threshold, the machine head flue gas is controlled to enter the bag filter 10 through the first pipeline unit 30. When the spark data is greater than the preset spark threshold, the machine head flue gas passes through the spark extinguishing device 42 and the alkalinity adjustment device 43 before entering the bag filter 10. This solves the problem that the filter bags are easily burned through due to the presence of sparks in the machine head flue gas when using the bag filter 10 for dust removal, and solves the technical problem of unstable operation of the existing sintering machine head flue gas bag filter system 100.

[0039] Understandably, the first pipeline unit 30 can be a duct; the spark extinguishing device 42 includes two working states. The first working state is to receive the flue gas from the bypass pipe 41 and guide the flue gas to the alkalinity regulating device 43. The second working state is to receive the flue gas from the bypass pipe 41, perform spark extinguishing treatment on the flue gas, and then guide the flue gas to the alkalinity regulating device 43. The alkalinity regulating device 43 includes two working states. The first working state is to receive the flue gas from the spark extinguishing device 42 and guide the flue gas to the bag filter 10. The second working state is to receive the flue gas from the bypass spark extinguishing device 42, perform alkaline ash spraying treatment on the flue gas, and then guide the flue gas to the bag filter 10. Specifically, when the spark extinguishing device 42 is working, it is used to receive the flue gas from the bypass pipe and spray water mist and / or carbon dioxide into the flue gas to extinguish the sparks in the flue gas. The alkalinity regulating device 43 is used to receive the flue gas treated by the spark extinguishing device 42 and spray alkaline ash into the flue gas during the process of introducing the flue gas into the bag filter 10 (if the acidity exceeds the standard, the alkalinity regulating device will spray alkaline ash). Alternatively, when the spark extinguishing device 42 is working, it is used to receive the flue gas from the bypass pipe and guide the flue gas to the alkalinity regulating device 43. The alkalinity regulating device 43 is used to receive the flue gas output by the spark extinguishing device 42 and introduce the flue gas into the bag filter 10.

[0040] Optionally, both the first control valve and the second control valve are pipeline control valves.

[0041] Please refer to Figure 3Furthermore, the dust collector frame 23 includes a rotating cone 231, a rotating drive mechanism 232, a dust collector filter 233, a dust collection trough 234, and a dust collector cylinder 235 having the hollow cavity. The top surface of the dust collector cylinder 235 is provided with the first discharge port, and the side wall of the dust collector cylinder is respectively provided with the initial flue gas inlet and the second discharge port. The second discharge port is located above the initial flue gas inlet. A mounting bracket is provided at the bottom opening of the dust collector cylinder 235. The dust collector filter 233 covers the rotating cone 231, and the dust collector cylinder 235 covers the rotating cone 231. Outside the rotating cone 231, a discharge gap is left between the dust removal filter hood 233 and the inner wall of the dust removal cylinder 235. The rotating drive mechanism 232 is mounted on the mounting frame. The rotating cone 231 is arranged vertically with its large diameter end facing the rotating drive mechanism 232. A spiral guide groove 2311 is recessed on the outer circumferential wall of the rotating cone 231. The dust collection trough 234 is located at the bottom of the dust removal cylinder 235. The air inlet pipe 22 passes through the initial flue gas inlet and the side wall of the dust removal filter hood 233 and is arranged towards the rotating cone 231. Understandably, the initial flue gas inlet, the second outlet, and the first outlet are arranged sequentially along the height of the dust collector cylinder 235. The rotary drive mechanism 232, mounted on the mounting frame, drives the rotating cone 231 to rotate around the central axis of the dust collector cylinder 235. The rotary drive mechanism 232 drives the rotating cone 231 to rotate, generating an upward swirling vortex force within the hollow cavity under the action of the spiral guide groove 2311. This causes the flue gas at the dust collector head to form a swirling flow. The flue gas entering from the bottom of the dust collector cylinder 235 moves upward under the action of the swirling flow. When the flue gas impacts the rotating cone 231, the flue gas... Large dust particles in the gas (mainly iron ore powder and return ore) impact the surface of the rotating cone 231 and fall directly into the ash collection trough 234. At the same time, unburned sparks impact the rotating cone 231 and are quickly extinguished. Small dust particles in the flue gas at the machine head pass through the dust collector filter 233 under the action of centrifugal force and fall into the ash collection trough 234. This achieves preliminary purification of the flue gas at the machine head and extinguishes sparks, reducing the working intensity of the bag filter 10. While preventing the bag filter 10 from being burned through by sparks, it also avoids the problem that the filter bags of the bag filter 10 are easily worn by large dust particles in the flue gas, resulting in a short service life.

[0042] Understandably, the rotary drive mechanism 232 can be a rotary drive motor, and the dust collection trough 234 can be a dust collection hopper, with a discharge valve at the bottom of the hopper. In this invention, the dust collection trough 234 is used to cover the bottom opening of the dust collector cylinder 235, thereby receiving dust falling from the hollow cavity; large dust particles slide laterally from the rotating cone 231 into the dust collection trough 234, and small dust particles fall laterally from the dust collector filter hood 233 into the dust collection trough 234. Optionally, the mounting bracket is installed at the bottom opening of the dust collector cylinder 235, and the rotating cone 231 is mounted on the mounting bracket.

[0043] Understandably, the dust collector filter hood 233 has filter holes, the diameter of which is set according to actual conditions. Specifically, the dust collector filter hood 233 includes a frustoconical section and a cylindrical section connected to each other, with the cylindrical section covering the rotating cone 231. Optionally, the spiral guide groove 2311 is an upward spiral groove.

[0044] Furthermore, fire extinguishing protrusions 236 are provided on the outer circumferential wall of the rotating cone 231, and the fire extinguishing protrusions 236 are staggered with the spiral guide groove 2311. In specific operation, the rotation of the rotating cone 231 causes the flue gas at the machine head to form a swirling flow. Large dust particles (mainly iron ore powder and return ore) in the flue gas impact the fire extinguishing protrusions 236 and fall into the ash collection trough 234; sparks in the flue gas impact the fire extinguishing protrusions 236 and extinguish them. Optionally, the shape of the fire extinguishing protrusions 236 can be rectangular, triangular, or other polygonal.

[0045] Please refer to Figure 4 Furthermore, the dust removal pretreatment device 20 also includes a primary temperature detector 237 installed on the air inlet pipe 22. The sintering machine head flue gas bag dust removal system 100 also includes a heating device 50 and a cooling device 60. The heating device 50 includes a hot air duct 51 for communicating with the hollow cavity, and a hot air control valve for controlling the on / off state of the hot air duct 51 is provided on the hot air duct 51. The cooling device 60 includes a cold air duct for communicating with the hollow cavity, and a cold air control valve for controlling the on / off state of the cold air duct is provided on the cold air duct. Understandably, if the primary temperature detector 237 detects a temperature lower than a preset temperature, high-temperature flue gas is injected into the hollow cavity through the hot air duct 51; if the primary temperature detector 237 detects a temperature higher than a preset temperature, low-temperature flue gas is injected into the hollow cavity through the hot air duct 51.

[0046] Specifically, the heating device 50 includes a hot air duct 51 and a combustion mechanism 52. The hot air duct 51 connects the combustion mechanism 52 and the dust collector cylinder 235. In this invention, the hot air duct 51 passes through the side wall of the dust collector filter hood 233 and faces the rotating cone 231. The combustion mechanism 52 includes a combustion chamber with a burner inside. The burner is externally connected to a gas pipe (preferably using surplus low-calorific-value blast furnace gas or converter gas from steel plants) and a combustion air duct. Both the gas pipe and the combustion air duct are equipped with flow regulating valves.

[0047] Optionally, the rotating cone 231, the dust filter hood 233, the dust collection trough 234, and the dust collector cylinder 235 are arranged coaxially, the rotating drive mechanism 232 is mounted on the mounting frame, and the first discharge port is located on the top surface of the dust collector cylinder 235 and is arranged coaxially with the dust collector cylinder 235.

[0048] In practical implementation, the dust collector cylinder 235 is arranged vertically. The bottom side wall of the dust collector cylinder 235 is provided with an initial flue gas inlet and a hot air guide pipe 51. The hot air guide pipe 51 is set opposite to the initial flue gas inlet. The top surface of the dust collector cylinder 235 is provided with a first discharge port, and the top side wall of the dust collector cylinder 235 is provided with a second discharge port. Based on the swirling flow generated by the rotation of the rotating cone 231, the first discharge port is located on the top surface of the dust collector cylinder 235, which helps to ensure the quality of the flue gas discharged from the first discharge port and helps to reduce the workload of the bag filter 10.

[0049] In practice, the initial spark probe is located on the air intake pipe 22 and downstream of the temperature monitor, and the cold air duct is located on the air intake pipe 22 and downstream of the temperature monitor. When the cold air duct is used for cooling, it helps to extinguish the sparks in the flue gas in the air intake pipe 22, further ensuring the safety of dust removal using a bag filter.

[0050] Please refer to Figure 5 , Figure 6 and Figure 7Furthermore, to ensure dust removal efficiency and avoid energy waste, the second pipeline unit 40 also includes a secondary spark monitor 44. The bypass pipe 41 connects the second discharge port and the spark extinguishing device 42, and the alkalinity adjusting device 43 connects the spark extinguishing device 42 and the bag filter 10. The secondary spark monitor 44 is mounted on the bypass pipe 41. Specifically, the secondary spark monitor 44 monitors the spark information entering the fire extinguishing cylinder 421. If the spark information is greater than a preset value, the spark extinguishing device 42 is controlled to extinguish the sparks, and the alkalinity adjusting device 43 is controlled to spray alkaline ash. If the spark information is not greater than the preset value, the spark extinguishing device 42 is controlled to guide the flue gas into the alkalinity adjusting device 43, and the alkalinity adjusting device 43 is controlled to guide the flue gas into the bag filter 10. Optionally, the fire extinguishing fluid spraying mechanism 422 is a water mist spraying mechanism, and the fire extinguishing gas spraying mechanism 423 is a carbon dioxide spraying mechanism.

[0051] Furthermore, the ratio of the diameter of the bypass pipe 41 to the diameter of the fire extinguishing cylinder 421 is 1:6-8. Understandably, a larger diameter results in a slower flow rate. By setting the ratio of the bypass pipe 41's diameter to the fire extinguishing cylinder 421's diameter to 1:6-8, the smoke flow velocity within the bypass pipe 41 is 16 m / s. After the smoke enters the fire extinguishing cylinder 421, the flow velocity decreases to less than 0.5 m / s. This slower flow rate is beneficial for fire extinguishing.

[0052] Furthermore, the fire extinguishing fluid spraying mechanism 422 includes a storage tank, a liquid booster pump, a liquid supply pipe, and a spraying plate. The spraying plate is located inside the fire extinguishing cylinder 421 and is coaxially arranged with the fire extinguishing cylinder 421. Spraying holes are provided on the circumferential wall surface of the spraying plate. The storage tank is located outside the fire extinguishing cylinder 421 and is connected to the spraying plate through the liquid supply pipe. The liquid booster pump is located on the liquid supply pipe.

[0053] Furthermore, the fire extinguishing gas injection mechanism 423 includes a gas storage tank, a gas booster pump, a gas supply pipe, and a injection disc. The injection disc is disposed inside the fire extinguishing cylinder 421 and is coaxially arranged with the fire extinguishing cylinder 421. The circumferential wall of the injection disc is provided with injection holes. The gas storage tank is disposed outside the fire extinguishing cylinder 421 and is connected to the injection disc through the gas supply pipe. The gas booster pump is disposed on the gas supply pipe.

[0054] In specific implementation, the spraying disc is located upstream of the spraying disc. The spraying disc includes multiple spraying annular discs that diffuse outward from the axis of the fire extinguishing cylinder 421. The liquid supply pipe is arranged radially along the fire extinguishing cylinder 421 and is located radially on the spraying disc, communicating with the corresponding spraying annular disc. The spraying disc includes multiple spraying annular discs that diffuse outward from the axis of the fire extinguishing cylinder 421. The gas supply pipe is arranged radially along the fire extinguishing cylinder 421 and is located radially on the spraying disc, communicating with the corresponding spraying annular disc. Specifically, there are four spraying annular discs, with the radial dimensions of adjacent spraying annular discs gradually increasing; there are also four spraying annular discs, with the radial dimensions of adjacent spraying annular discs gradually increasing.

[0055] Please refer to Figure 8 Furthermore, the bypass pipe 41 is equipped with an acidity detector 45, and the alkalinity adjustment device 43 includes an alkalinity adjustment cylinder 431, an ash collection box 432, and an alkaline ash spraying mechanism 433. The alkalinity adjustment cylinder 431 is arranged vertically, with a bottom smoke inlet on the bottom side wall and a top smoke outlet on the top side wall. The ash collection box 432 is located at the bottom ash outlet of the alkalinity adjustment cylinder 431. The bottom smoke inlet is connected to the spark extinguishing device 42 through a secondary connecting pipe. The alkaline ash spraying mechanism 433 includes an alkaline ash spraying pipe arranged radially along the alkalinity adjustment cylinder 431. The alkaline ash spraying pipe is located at the top of the alkalinity adjustment cylinder 431 and below the top smoke outlet. The bottom surface of the alkaline ash spraying pipe is provided with an alkaline ash spraying head facing the bottom ash outlet. Understandably, applying alkali ash to the fire extinguishing fluid spraying mechanism 422 and the fire extinguishing gas spraying mechanism 423 through the alkalinity adjustment device 43 is beneficial to improving the service life of the bag filter 10.

[0056] More preferably, the ratio of the pipe diameter to the cylinder diameter of the alkalinity regulating cylinder 431 is 1:4-6. The larger the diameter, the slower the flow rate. Typically, the ratio of the pipe diameter to the cylinder diameter of the alkalinity regulating cylinder 431 is 1:4-6. The flue gas velocity inside the pipe is 16 m / s, and after the flue gas enters the alkalinity regulating cylinder 431, the flow rate decreases to less than 1 m / s. The slow flow rate is conducive to the reaction between the ash and the acidic gases in the flue gas.

[0057] Specifically, the liquid storage tank is an insulated liquid tank, and the gas storage tank is an insulated gas tank. The insulated liquid tank is conducive to the spraying of water mist at 80-98 degrees Celsius.

[0058] Specifically, the alkali ash spraying mechanism 433 includes an alkali ash storage box sleeved outside the alkalinity regulating cylinder 431 and an alkali ash spraying pipe radially disposed inside the alkalinity regulating cylinder 431. The alkali ash storage box and the alkali ash spraying pipe are connected by a pipeline. Specifically, the alkali ash storage box is an insulated storage box. The inner cavity of the insulated storage box is equipped with an electric heater, and the outer wall is equipped with an insulation layer. The alkali ash can be heated during storage, which not only ensures high activity and easy removal of acidic gases but also minimizes the impact on flue gas temperature.

[0059] Furthermore, the alkalinity adjusting device 43 also includes a reflection mechanism 434, which includes a horizontally arranged first reflection plate and an inclined second reflection plate. The first reflection plate is located between the ash spray head and the top smoke outlet, and has a first air hole that penetrates vertically through it. The second reflection plate is inclined at the inlet position of the top smoke outlet to allow filtered flue gas to enter the top smoke outlet. The air inlet side of the second reflection plate is inclined downwards vertically, and has a second air hole that penetrates it. In actual operation, the placement of the first reflection plate above the ash spray pipe helps to prevent ash from being discharged into the bag filter 10, and the placement of the second reflection plate between the first reflection plate and the top smoke outlet further filters the ash, further reducing the amount of ash discharged into the bag filter 10.

[0060] Specifically, the first air hole is an inverted frustum shape along the larger air inlet, and the diameter of the first air hole gradually expands outward along the height direction of the first reflector. The second air hole is an inverted frustum shape along the smaller air inlet, and the diameter of the second air hole gradually expands outward along the height direction of the second reflector.

[0061] More preferably, multiple first reflective plates are arranged at intervals along the height direction of the alkalinity adjusting cylinder 431, and the first air holes of the vertically adjacent first reflective plates are staggered.

[0062] The sintering machine head flue gas bag filter system 100 provided by the present invention has the following beneficial effects:

[0063] First, the primary spark detector 21 can detect whether there are sparks in the flue gas entering the dust removal pretreatment device 20. When there are sparks, the first control valve is closed and the second control valve is opened. The flue gas enters the spark extinguishing device 42 to remove the sparks and then enters the bag filter 10 through the alkalinity adjustment device 43. Meanwhile, by setting up the dust removal pretreatment device 20, when the flue gas impacts the rotating cone 231, large dust particles (mainly iron ore powder and return ore) in the flue gas impact the extinguishing protrusion 236 and fall into the ash collection tank 234. At the same time, unburned sparks can also be quickly extinguished after impacting the extinguishing protrusion 236. The rotating drive mechanism 232 drives the rotating cone 231 to rotate, causing the flue gas to form a vortex. The dust in the flue gas passes through the dust removal filter 233 under the action of centrifugal force and falls into the ash collection tank 234. The secondary spark detector 44 in the bypass pipe 41 continues to detect sparks in the flue gas after pre-dust removal. Based on whether there are sparks, it determines whether the subsequent spark extinguishing device 42 and alkalinity adjustment device 43 should be activated, realizing further spark monitoring after dust removal and spark extinguishing in the dust removal pretreatment device 20. Specifically, if the secondary spark detector 44 detects a spark, the flue gas first passes through the extinguishing fluid spraying mechanism 422, where the sprayed atomized water extinguishes the spark in the flue gas. Furthermore, the downstream extinguishing gas spraying mechanism 423 further sprays carbon dioxide, causing any remaining faint sparks in the flue gas to be completely extinguished due to oxygen deficiency as they pass through the high-concentration carbon dioxide area. By setting up the rotating cone 231, the combined action of the spark impact loss mechanism, the extinguishing fluid spraying mechanism 422, and the extinguishing gas spraying mechanism 423 ensures that sparks in the flue gas are completely removed, preventing them from entering the bag filter 10.

[0064] Secondly, it can effectively prevent acid corrosion of the filter bags in the baghouse dust collector 10. The alkalinity adjustment device 43 can effectively regulate the alkalinity of the flue gas. Specifically, the sulfur oxide concentration detector (acid detector 45) installed in the inner cavity of the connecting pipe detects that when the sulfur oxide content is high (the water spraying by the spark extinguishing device 42 causes an increase in the moisture content in the flue gas, the temperature will decrease slightly, and the condensation of acidic gases may increase), it feeds the signal back to the control system of the alkalinity adjustment device 43, which controls the alkaline ash spraying pipe to spray alkaline ash into the control cavity. The alkaline ash can react with the acidic gases in the flue gas, regulate the alkalinity of the flue gas, and effectively prevent acidic gases from entering the filter bags of the baghouse dust collector 10 and causing acid condensation to corrode the filter bags.

[0065] Third, it can effectively solve the problem that the filter bags of the existing sintering flue gas baghouse dust collector 10 are easily worn by large particles of dust in the flue gas (especially iron ore powder and return ore particles with high hardness and large particle size), resulting in a short service life. Specifically, when the flue gas enters the dust removal pretreatment device 20 and impacts the rotating cone 231, the large particles of dust in the flue gas (mainly iron ore powder and return ore) fall into the dust collection tank 234 after impacting the fire extinguisher. After being treated by the dust removal pretreatment device 20, the large particles of dust in the flue gas can be effectively removed, effectively solving the problem of large particles of dust entering the baghouse dust collector 10 and wearing down the filter bags.

[0066] Fourth, it can effectively regulate the temperature of sintering flue gas, keeping the temperature within a small fluctuation range, ensuring high safety and stability, and improving the dust removal efficiency of the bag filter 10. Specifically, the invention includes a temperature control device. When the primary temperature detector 237 detects an excessively high temperature, low-temperature flue gas (lower than the current flue gas temperature) is injected into the dust collector frame 23 through the cold air duct; when the primary temperature detector 237 detects an excessively low temperature, low-temperature flue gas (higher than the current flue gas temperature) is injected into the dust collector frame 23 through the hot air duct 51, effectively regulating the flue gas temperature. It should be noted that regardless of whether hot or cold air is introduced, the flue gas can swirl within the hollow cavity under the action of the rotating cone 231, ensuring thorough mixing and maintaining a relatively uniform temperature and composition of the flue gas.

[0067] The present invention also provides a method for baghouse dust collection of flue gas from a sintering machine head, used in the aforementioned baghouse dust collection system 100 for flue gas from a sintering machine head, comprising the following steps:

[0068] Temperature data of the flue gas entering the dust collector frame 23 through the intake pipe 22 is obtained by a primary temperature sensor. If the temperature data is greater than a preset temperature threshold, low-temperature flue gas is injected into the dust collector frame 23 through a cold air duct. If the temperature data is less than the preset temperature threshold, high-temperature flue gas is injected into the dust collector frame 23 through a hot air duct 51. Spark data of the flue gas entering the dust collector frame 23 through the primary spark monitor 21 is obtained. If the spark data is within a preset spark threshold range, the dust pretreatment device 20 is connected to the bag filter 10 through the first pipeline unit 30 to form a first flue gas emission treatment path. When the sparks are not within the preset spark threshold range, the dust removal pretreatment device 20 is connected to the bag filter 10 through the second pipeline unit 40 to form a second flue gas emission treatment path; the spark parameters of the flue gas entering the spark extinguishing device 42 through the bypass pipe 41 are obtained by the secondary spark monitor 21. If the spark parameters are not within the preset parameter threshold range, the spark extinguishing device 42 is activated to spray extinguishing fluid and / or extinguishing gas into the flue gas flowing through the spark extinguishing device 42. The acidity information of the flue gas entering the alkalinity adjustment device 43 is obtained. If the acidity information is less than the preset acidity threshold, the alkalinity adjustment device 43 is activated to spray alkaline ash into the flue gas flowing through the alkalinity adjustment device 43 and guide the flue gas to the bag filter 10.

[0069] Understandably, in this invention, the flue gas output after combustion in the heating device 50 is high-temperature flue gas, which is used to mix with the flue gas in the dust removal pretreatment device 20 to increase its internal flue gas temperature; the flue gas output by the cooling device 60 is low-temperature flue gas, which is used to mix with the flue gas in the dust removal pretreatment device 20 to reduce its internal flue gas temperature; wherein, the preset temperature value is set according to the actual situation.

[0070] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A baghouse dust collection system for sintering machine head flue gas, characterized in that, The system includes a baghouse dust collector, a dust pretreatment device, a first piping unit, and a second piping unit. The first discharge port of the dust pretreatment device is connected to the baghouse dust collector via the first piping unit, and the second discharge port of the dust pretreatment device is connected to the baghouse dust collector via the second piping unit. The second piping unit includes a bypass pipe, a spark extinguishing device, and an alkalinity adjusting device arranged sequentially and connected to each other. The dust pretreatment device includes a primary spark detector, an inlet pipe, and a dust collection frame with a hollow cavity. The dust collection frame has a connection to the hollow cavity... The cavity includes an initial flue gas inlet, a first outlet, and a second outlet. An intake pipe is located at the initial flue gas inlet and communicates with the hollow cavity. A primary spark detector is mounted on the intake pipe. The first outlet is connected to the bag filter via a first piping unit, and the second outlet is connected to the bag filter via a second piping unit. The first piping unit has a first control valve for controlling the on / off state of the first piping unit, and the second piping unit has a second control valve for controlling the on / off state of the second piping unit. The dust collector frame includes a rotating cone, a rotating drive mechanism, a dust collector filter hood, a dust collection trough, and a dust collector cylinder with the hollow cavity. The top surface of the dust collector cylinder has a first discharge port, and the side walls of the dust collector cylinder have an initial flue gas inlet and a second discharge port, with the second discharge port located above the initial flue gas inlet. A mounting bracket is provided at the bottom opening of the dust collector cylinder. The dust collector filter hood covers the rotating cone, and the dust collector cylinder covers the rotating cone. The dust collector filter hood and the dust collector cylinder... A discharge gap is left between the inner wall surfaces. The rotary drive mechanism is mounted on the mounting frame. The rotary cone is arranged vertically with its large-diameter end facing the rotary drive mechanism. A spiral guide groove is recessed on the outer circumferential wall surface of the rotary cone. The ash collection trough is located at the bottom of the dust collector cylinder. The air inlet pipe passes through the initial flue gas inlet and the side wall surface of the dust collector filter and is arranged towards the rotary cone. A fire extinguishing protrusion is protruded on the outer circumferential wall surface of the rotary cone. The fire extinguishing protrusion is staggered with the spiral guide groove.

2. The sintering machine head flue gas bag filter system according to claim 1, characterized in that, The dust removal pretreatment device also includes a primary temperature detector installed on the air inlet pipe. The sintering machine head flue gas bag filter system also includes a heating device and a cooling device. The heating device includes a hot air duct for communicating with the hollow cavity, and a hot air control valve for controlling the on / off state of the hot air duct is provided on the hot air duct. The cooling device includes a cold air duct for communicating with the hollow cavity, and a cold air control valve for controlling the on / off state of the cold air duct is provided on the cold air duct.

3. The sintering machine head flue gas bag filter system according to any one of claims 1 or 2, characterized in that, The second pipeline unit also includes a secondary spark monitor. The bypass pipe is used to connect the second discharge port and the spark extinguishing device. The alkalinity adjustment device is used to connect the spark extinguishing device and the bag filter. The secondary spark monitor is located on the bypass pipe.

4. The sintering machine head flue gas bag filter system according to claim 3, characterized in that, The spark extinguishing device includes an extinguishing cylinder, an extinguishing fluid spraying mechanism, and an extinguishing gas spraying mechanism. The extinguishing cylinder is arranged horizontally, with its axial end air inlet connected to the output end of the bypass pipe, and its axial end air outlet connected to the input port of the alkalinity adjusting device. The fire extinguishing fluid spraying mechanism and the fire extinguishing gas spraying mechanism are arranged at intervals along the axial direction of the fire extinguishing cylinder. The fire extinguishing fluid spraying mechanism is used to spray atomized fluid into the fire extinguishing cylinder, and the fire extinguishing gas spraying mechanism is used to spray fire extinguishing gas into the fire extinguishing cylinder.

5. The sintering machine head flue gas bag filter system according to claim 4, characterized in that, The fire extinguishing fluid spraying mechanism includes a storage tank, a liquid booster pump, a supply pipe, and a spraying plate. The spraying plate is located inside the fire extinguishing cylinder and is coaxially arranged with the fire extinguishing cylinder. Spray holes are provided on the circumferential wall of the spraying plate. The storage tank is located outside the fire extinguishing cylinder and is connected to the spraying plate through the supply pipe. The liquid booster pump is located on the supply pipe, and / or The fire extinguishing gas injection mechanism includes a gas storage tank, a gas booster pump, a gas supply pipe, and a injection disc. The injection disc is located inside the fire extinguishing cylinder and is coaxially arranged with the fire extinguishing cylinder. The circumferential wall of the injection disc is provided with injection holes. The gas storage tank is located outside the fire extinguishing cylinder and is connected to the injection disc through the gas supply pipe. The gas booster pump is located on the gas supply pipe.

6. The sintering machine head flue gas bag filter system according to claim 3, characterized in that, An acid detector is installed inside the bypass pipe. The alkalinity regulating device includes an alkalinity regulating cylinder, an ash collection box, and an alkaline ash spraying mechanism. The alkalinity regulating cylinder is vertically arranged, with a bottom smoke inlet on its bottom side wall and a top smoke outlet on its top side wall. The ash collection box is located at the bottom ash outlet of the alkalinity regulating cylinder. The bottom smoke inlet is connected to the spark extinguishing device via a secondary connecting pipe. The alkali ash spraying mechanism includes an alkali ash spraying pipe arranged radially along the alkalinity regulating cylinder. The alkali ash spraying pipe is located at the top of the alkalinity regulating cylinder and below the top smoke outlet. An alkali ash spraying head is provided on the bottom surface of the alkali ash spraying pipe and is arranged towards the bottom ash outlet.

7. The sintering machine head flue gas bag filter system according to claim 6, characterized in that, The alkalinity adjusting device further includes a reflection mechanism, which comprises a first reflection plate arranged horizontally and a second reflection plate arranged at an angle. The first reflector plate is disposed between the ash spray head and the top smoke outlet, and the first reflector plate has a first air hole that penetrates the first reflector plate vertically. The second reflector is inclined at the inlet position of the top smoke outlet to allow the smoke to enter the top smoke outlet after being filtered. The air inlet side of the second reflector is inclined downwards vertically, and the second reflector is provided with a second air hole that penetrates the second reflector.

8. A method for baghouse dust collection of flue gas from a sintering machine head, characterized in that, The sintering machine head flue gas bag filter system as described in any one of claims 1 to 7 comprises the following steps: The temperature data of the flue gas entering the dust collector frame through the air intake pipe is obtained by a primary temperature sensor; if the temperature data is greater than a preset temperature threshold, low-temperature flue gas is injected into the dust collector frame through a cold air duct; if the temperature data is less than the preset temperature threshold, high-temperature flue gas is injected into the dust collector frame through a hot air duct. The primary spark monitor acquires spark data of the flue gas entering the dust collector frame through the intake pipe; if the spark data is within a preset spark threshold range, the dust pretreatment device is connected to the bag filter through the first pipeline unit to form a first flue gas emission treatment path; if the spark data is not within the preset spark threshold range, the dust pretreatment device is connected to the bag filter through the second pipeline unit to form a second flue gas emission treatment path. The secondary spark monitor acquires the spark parameters of the flue gas entering the spark extinguishing device through the bypass pipe. If the spark parameters are not within the preset parameter threshold range, the spark extinguishing device is activated to spray extinguishing fluid and / or extinguishing gas onto the flue gas flowing through it. The acidity information of the flue gas entering the alkalinity adjustment device is acquired. If the acidity information is less than the preset acidity threshold, the alkalinity adjustment device is activated to spray alkaline ash onto the flue gas flowing through it and guide the flue gas to the bag filter.

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