Dust removal equipment for flue gas in the flue of the alumina production line roasting furnace

Abstract

The present invention proposes a dust removal device for flue gas of a roasting furnace in an alumina production line, including a bag filter, a dust removal fan, a Y-type dust removal air intake pipe, an upflow pipe, a downflow pipe, an elbow, a cross breathing flow component and a pre-dust removal component. The cross breathing flow component includes an axial flow venturi, a breathing venturi, a conical one-way valve assembly, a cap tube, an end cover and an elastic filter assembly; the pre-dust removal component includes a transition flue, a through port, a dust removal jacket, a dust collection tube, a dust collection port and an extraction tube. The present invention utilizes the cross breathing flow component to replenish air in real time, promotes the flow of flue gas in the pre-treatment direction, and utilizes the disturbance generated by the replenished air and the increased flue gas flow rate to avoid dust retention; the pre-dust removal component can block part of the dust in the extraction tube, and the impact force generated by the flue gas at the end of the transition flue can stir up the dust on the elbow side, so that the flowing flue gas carries the dust to the bag filter, which is beneficial to improving the dust treatment performance and ensuring the performance of the roasting furnace.

Description

Technical Field

[0001] The invention belongs to the technical field of aluminum oxide production, relates to a roasting furnace, and in particular to dust removal equipment for flue gas in a smoke duct of a roasting furnace in an aluminum oxide production line. Background Art

[0002] The alumina production process is divided into the sintering process, the Bayer process or a mixture of the two. Most of them use the Bayer process. Its main production processes include: ore blending, slurry preparation, pre-desiliconization, high-pressure dissolution, red mud separation and washing, crude liquid refining, seed decomposition, aluminum hydroxide washing and filtration, roasting, and mother liquor evaporation. In the alumina production process, different equipment is needed to dispose of industrial solid waste, such as steel slag disposal equipment, flue dust removal equipment, silicon manganese slag disposal equipment, iron slag disposal equipment, fly ash disposal equipment, power plant incineration waste disposal equipment and sludge disposal equipment. Among them, flue dust removal equipment mainly involves roasting furnace section and clinker rotary kiln section.

[0003] At present, most roasting furnace flue gas dust removal equipment uses multiple bag dust collectors, which can be used in parallel or in series, such as the existing patent CN208526133U discloses an alumina roasting furnace flue gas treatment device and CN205279767U discloses a roasting furnace flue gas treatment system. Such a flue gas dust removal system mostly acts on the end of the flue gas flow direction, and for the flue directly connected to the exhaust part of the roasting furnace, due to the strong power of the flue gas and low density, a part of the smoke and dust falls on the initial section of the flue after rising, and the horizontal flue leads the flue gas to the elbow and needs to turn into the baffle direction. The vortex generated in the elbow will block the smoke and dust in the initial section of the flue, causing a part of the dust to always linger at the top of the flue, affecting the effect of treating the dust in the initial section of the flue. Summary of the invention

[0004] In view of the technical problems existing in the above-mentioned dust removal equipment, the present invention proposes a dust removal equipment for the flue gas of the alumina production line roasting furnace, which has a reasonable design, good diversion effect, is beneficial to improving the dust handling performance and ensuring the performance of the roasting furnace.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is that the dust removal equipment for the flue gas of the flue of the roasting furnace of the alumina production line provided by the present invention includes a bag dust collector and a dust removal fan, the top of the bag dust collector is provided with a Y-shaped dust removal air inlet pipe, the input side of the Y-shaped dust removal air inlet pipe is provided with an upflow pipe and a downflow pipe constituting a U-shaped conveying path, the top of the downflow pipe is provided with an elbow, the input side of the elbow is used to connect with the roasting furnace, the input side of the elbow is provided with a cross breathing flow component and a pre-dust removal component connected front and back, the cross breathing flow component includes an axial flow Venturi tube and a breathing Venturi tube connected with the axial flow Venturi tube in a cross manner, the cross connection node between the axial flow Venturi tube and the breathing Venturi tube is located at the center position of the two, one end of the axial flow Venturi tube is connected to the roasting furnace and the other end is connected to the A pre-dust removal component is connected, a conical one-way valve assembly is arranged inside the breathing venturi, a cap barrel connected to its flange is arranged at the end of the breathing venturi, an annular end cover is arranged at the end of the cap barrel, and an elastic filter assembly is arranged between the end cover and the cap barrel; the pre-dust removal component includes a transition flue connecting the axial flow venturi and the elbow front and back, the transition flue is a two-stage stepped structure and its pipe diameter facing the end of the axial flow venturi is larger than the pipe diameter facing the end of the elbow, a plurality of through openings distributed in the lower half of the transition flue are arranged at the stepped transition position, a dust removal jacket is arranged outside the transition flue, a dust collection barrel is arranged at the bottom of the dust removal jacket, a dust collection port is arranged at the position of the dust collection barrel corresponding to the through opening, and a suction barrel telescopically matched with the dust collection barrel is arranged at the bottom.

[0006] Preferably, the conical one-way valve assembly includes a conical cylinder, the outer side of which is provided with a quick-retractable support connected to the breathing venturi, the end of the conical cylinder facing the center of the cross breathing flow component is an open structure, the other end of the conical cylinder is provided with a bowl-shaped valve core elastically matched therewith, the center of the bowl-shaped valve core is provided with a valve stem, the valve stem is movably matched with a telescopic opening provided on the conical cylinder, a balancing spring is sleeved on the valve stem, the balancing spring is located inside the conical cylinder, the end of the balancing spring is provided with a limit plate and a stop nut connected to the valve stem, and the end of the bowl-shaped valve core facing away from the conical cylinder is movably matched with a conical valve plate provided on the cap tube.

[0007] Preferably, the rapid telescopic support member includes three supporting cylinders evenly distributed on the conical cylinder, three positioning cylinders corresponding to the supporting cylinders are arranged on the inner wall of the respiratory venturi, a compression cylinder nested with the positioning cylinder is arranged on the supporting cylinder, the cylinder mouth of the compression cylinder is opposite to the cylinder mouth of the supporting cylinder, support springs are arranged inside the compression cylinder and the supporting cylinder, a pair of guide columns are arranged outside the compression cylinder, and the guide columns are slidably matched with the guide openings arranged on the supporting cylinder.

[0008] Preferably, the elastic filter assembly comprises an inner tank body and an outer tank body which are nested with each other, and a plurality of stacked metal filter screens are arranged between the inner tank body and the outer tank body.

[0009] Preferably, the dust collecting cylinder is of an n-type structure, the number of the suction cylinders is two and they respectively cooperate with the two branches of the dust collecting cylinder, a vertical slider is arranged on the inner wall of the dust collecting cylinder, and a sliding groove which frictionally cooperates with the slider is arranged on the side of the suction cylinder.

[0010] Preferably, a diverter block is provided at the inner top of the elbow, the end of the diverter block facing the transition flue is a crescent-shaped surface, the thickness of the diverter block gradually decreases from the crescent-shaped surface to the other end of the diverter block, and the side of the diverter block facing the inner bottom surface of the elbow is a cylindrical curved surface.

[0011] Preferably, the pre-dust removal component is connected to the upstream pipe through an air flotation component, and the upstream pipe is provided with a plug valve for adjusting the flow of the air flotation component.

[0012] Preferably, the air flotation assembly comprises two three-dimensional Z-shaped tubes connected to the bottom of the pumping tube, the three-dimensional Z-shaped tubes comprise a plurality of vertical sections and oblique sections, and the diameter of the three-dimensional Z-shaped tubes is smaller than 1 / 2 of the diameter of the pumping tube.

[0013] Preferably, the plug valve comprises a double-headed flange pipe, a bevel joint pipe connected to the spatial three-dimensional Z-shaped pipe is arranged on the pipe side of the double-headed flange pipe, the vertical section of the bevel joint pipe is trapezoidal, a valve cylinder is arranged inside the double-headed flange pipe, the mouth of the valve cylinder faces downward and a plurality of valve openings of different calibers are arranged on its side, and the valve openings are used to connect the bevel joint pipe.

[0014] Preferably, a clamp member is provided on the side of the downflow pipe for connecting the downflow pipe and the vertical section of the spatial three-dimensional Z-shaped pipe at the same time.

[0015] Compared with the prior art, the advantages and positive effects of the present invention are:

[0016] 1. The dust removal equipment for flue gas in the flue of the roasting furnace of the alumina production line provided by the present invention utilizes the cross breathing flow component to work under pressure conditions, and can replenish air from two directions in real time to promote the flow of flue gas in the pre-treatment direction, and utilizes the disturbance generated by the replenished air and the increased flue gas flow to prevent dust from adhering to the section between the elbow and the roasting furnace; the pre-dust removal component can block part of the dust in the suction tube, and the impact force generated by the flue gas at the end of the transition flue can stir up the dust on the elbow side, so that the flowing flue gas carries the dust to the bag filter, thereby further improving the treatment effect of the device on the flue gas. The device is reasonably designed, conducive to improving the dust treatment performance and ensuring the performance of the roasting furnace, and is suitable for large-scale promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 An axonometric diagram of a dust removal device for flue gas in a flue of an alumina production line roasting furnace provided in an embodiment;

[0019] Figure 2 A front view of a dust removal device for flue gas from a flue of an alumina production line roasting furnace provided in an embodiment;

[0020] Figure 3 An axonometric view of a cross breathing flow component, a pre-dust removal component, and an air flotation assembly provided for an embodiment;

[0021] Figure 4 An exploded view of a cross breathing flow component provided for an embodiment;

[0022] Figure 5 A side view of a cross breathing flow component, a pre-dust removal component and an air flotation assembly provided for an embodiment;

[0023] Figure 6 A cross-sectional view of a cross breathing flow component, a pre-dust removal component and an air flotation component provided in an embodiment in the DD direction;

[0024] Figure 7 A cross-sectional view of a cross breathing flow component, a pre-dust removal component and an air flotation component in the EE direction provided in an embodiment;

[0025] Figure 8 A cross-sectional view of a cross breathing flow component, a pre-dust removal component and an air flotation component provided in an embodiment in the GG direction;

[0026] Fig. 9 An exploded view of a pre-dust removal component provided in an embodiment;

[0027] Fig.10 An axonometric view of a flow diverter block provided for an embodiment;

[0028] Fig.11 A cross-sectional view of a valve cartridge provided for an embodiment;

[0029] In the above figures, 1. bag filter; 2. dust removal fan; 3. Y-type dust removal air intake pipe; 4. upstream pipe; 5. downstream pipe; 6. elbow; 7. cross breathing flow component; 71. axial flow venturi; 72. breathing venturi; 73. cone check valve assembly; 731. cone cylinder; 732. quick telescopic support; 7321. support cylinder; 7322. positioning cylinder; 7323. compression cylinder; 7324. support spring; 7325. guide column; 7326. guide port; 733. bowl-shaped valve core; 734. valve stem; 735. telescopic port; 736. balance spring; 737. limit plate; 73 8. Check nut; 739. Conical valve plate; 74. Cap tube; 75. Elastic filter assembly; 751. Inner tank body; 752. Outer tank body; 753. Metal filter screen; 76. End cover; 8. Pre-dust removal component; 81. Transition flue; 82. Through port; 83. Dust removal jacket; 84. Dust collection cylinder; 85. Dust collection port; 86. Extractor cylinder; 87. Slider; 88. Slide; 9. Flow pick; 10. Flotation assembly; 101. Three-dimensional Z-shaped tube; 102. Plug valve; 1021. Double-head flange tube; 1022. Bevel joint tube; 1023. Valve cylinder; 1024. Valve port; 103. Hoop. DETAILED DESCRIPTION

[0030] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described below in conjunction with the accompanying drawings and embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict. For the convenience of description, if the words "upper", "lower", "left" and "right" appear below, they only indicate that the upper, lower, left and right directions are consistent with the accompanying drawings themselves, and do not limit the structure.

[0031] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments of the following disclosure.

[0032] Examples, such as Figures 1 to 11 As shown, the dust removal equipment for flue gas of the flue of the roasting furnace of the alumina production line provided by the present invention includes a bag filter 1 and a dust removal fan 2. A Y-shaped dust removal air inlet pipe 3 is arranged on the top of the bag filter 1. An upflow pipe 4 and a downflow pipe 5 constituting a U-shaped conveying path are arranged on the input side of the Y-shaped dust removal air inlet pipe 3. An elbow 6 is arranged on the top of the downflow pipe 5. The input side of the elbow 6 is used to connect the roasting furnace. Among them, the number and processing specifications of the bag filter 1 are flexibly selected according to the volume of the alumina production capacity. The elbow 6, downflow pipe 5, upflow pipe 4 and Y-shaped dust removal air inlet pipe 3 used to form the roasting furnace to the bag filter 1 are prior art, and this embodiment will not be repeated here.

[0033] On this basis, the input side of the elbow 6 provided by the present invention is provided with a cross breathing flow component 7 and a pre-dust removal component 8 connected front and back, the cross breathing flow component 7 includes an axial flow Venturi tube 71 and a breathing Venturi tube 72 connected to the axial flow Venturi tube 71 in a cross manner, the cross connection node between the axial flow Venturi tube 71 and the breathing Venturi tube 72 is located at the center position of the two, one end of the axial flow Venturi tube 71 is connected to the roasting furnace and the other end is connected to the pre-dust removal component 8, a conical one-way valve assembly 73 is provided inside the breathing Venturi tube 72, and a cap barrel 74 connected to its flange is provided at the end of the breathing Venturi tube 72, and an annular end cover 76 is provided at the end of the cap barrel 74, and the end cover An elastic filter assembly 75 is arranged between 76 and the cap tube 74; the pre-dust removal component 8 includes a transition flue 81 connecting the axial flow Venturi tube 71 and the elbow 6 front and rear, the transition flue 81 is a two-level stepped structure and the tube diameter at the end facing the axial flow Venturi tube 71 is larger than the tube diameter at the end facing the elbow 6, a plurality of through openings 82 distributed in the lower half of the transition flue 81 are arranged at the stepped transition position, a dust removal jacket 83 is arranged on the outside of the transition flue 81, a dust collection barrel 84 is arranged at the bottom of the dust removal jacket 83, a dust collection port 85 is arranged at the position of the dust collection barrel 84 corresponding to the through opening 82, and a suction barrel 86 telescopically matched with the dust collection barrel 84 is arranged at the bottom.

[0034] Specifically, the cross breathing flow component 7 uses two venturi tubes, which can increase the flow rate of the fluid entering the pretreatment component, which is conducive to promoting the dust carried in the flue gas to fall on the section between the roasting furnace and the elbow 6. Further, the axial flow venturi tube 71 builds a section from the roasting furnace to the pretreatment component for the flue gas, and when the flue gas passes through the axial flow venturi tube 71, the pressure conditions generated in the breathing venturi tube 72 can make the two ends of the breathing venturi tube 72 replenish air in real time from two directions at the same time, thereby promoting the flue gas to flow in the pretreatment direction, and using the disturbance generated by the replenished air and the flue gas after the flow rate and flow rate are increased to avoid dust from adhering to the section between the elbow 6 and the roasting furnace. In the cross breathing flow component 7, the elastic filter component 75 can filter the large particles carried by the air entering the breathing venturi tube 72 from the outside, and the actual working density of the elastic filter component 75 can be dynamically adjusted with the change of pressure in the breathing venturi tube 72, which is conducive to improving its filtering effect. Due to the complexity and harmfulness of smoke components, the present invention provides a conical one-way valve assembly 73 to ensure that gas can only enter from the outside to the inside, and prohibits smoke from being directly discharged from the inside to the outside. In addition, the conical airflow cavity formed by the conical one-way valve assembly 73 and the breathing venturi 72 can effectively promote the airflow to enter the axial flow venturi 71, which is beneficial to improving the breathing performance of the present device.

[0035] Regarding the pre-dust removal component 8, the flue gas accelerated from the axial flow venturi 71 into the transition flue 81, the smoke carried by it generates a deflection at the stepped transition part of the transition flue 81, which can block part of the dust in the exhaust tube 86, and the flue gas at the end of the transition flue 81 can generate an upward impact force to stir up the dust between the transition flue 81 and the elbow 6, and the flowing flue gas will carry the stirred dust to the output side of the elbow 6, and then enter the bag filter 1 in an orderly manner to complete the treatment, thereby further improving the treatment effect of the device on the flue gas, especially for the dust on the section between the roasting furnace and the elbow 6, which is beneficial to ensure the performance of the roasting furnace. Among them, the dust removal jacket 83 is used to seal the transition flue 81 to prevent large-scale leakage of flue gas; the space between the exhaust tube 86 and the dust collection tube 84 can be adjusted by pulling.

[0036] In order to improve the automatic control performance of the conical one-way valve assembly 73 on the airflow, the conical one-way valve assembly 73 provided by the present invention includes a conical cylinder 731, and a fast telescopic support member 732 connected to the breathing venturi 72 is arranged on the outer side of the conical cylinder 731. The end of the conical cylinder 731 facing the center of the cross breathing flow component 7 is an open structure, and the other end of the conical cylinder 731 is provided with a bowl-shaped valve core 733 elastically matched therewith, and a valve stem 734 is arranged at the center of the bowl-shaped valve core 733. The valve stem 734 and the device The telescopic opening 735 disposed on the cone 731 is movably matched, the valve stem 734 is sleeved with a balance spring 736, the balance spring 736 is located inside the cone 731, and the end of the balance spring 736 is provided with a limit plate 737 and a stop nut 738 connected to the valve stem 734, and the end of the bowl-shaped valve core 733 facing away from the cone 731 is movably matched with the conical valve plate 739 disposed on the cap tube 74, and the center of the cap tube 74 is hollow and concentric with the end of the conical valve plate 739 and has the same diameter. Among them, the quick telescopic support 732 can facilitate the installation of the cone 731, so that the cone 731 can maintain a coaxial working position with the respiratory venturi 72. The conical valve plate 739 and the bowl-shaped valve core 733 have conical surfaces that can be sealed and matched, and the bowl-shaped valve core 733 is pulled by the balance spring 736 and leans against the end of the cone 731 in a natural state, so that the negative pressure can draw the external air through the elastic filter assembly 75, through the gap between the conical valve plate 739 and the bowl-shaped valve core 733, and then through the conical gap between the cone 731 and the breathing venturi 72 to achieve multiple pressurization and acceleration and enter the axial flow venturi 71. The axial flow venturi 71 draws smoke, and the smoke flow can further promote the air to enter the axial flow venturi 71. For the reverse smoke, the smoke enters the cone 731 and pushes the bowl-shaped valve core 733 to move toward the conical valve plate 739, and the spring is compressed at the same time until the conical valve plate 739 and the bowl-shaped valve core 733 complete the seal, thereby achieving the effect of blocking the flow.

[0037] In order to improve the practicality of the quick-retractable support member 732, the quick-retractable support member 732 provided by the present invention includes three support cylinders 7321 evenly distributed on the conical cylinder 731, three positioning cylinders 7322 corresponding to the support cylinders 7321 are arranged on the inner wall of the respiratory venturi 72, and a compression cylinder 7323 nested with the positioning cylinder 7322 is arranged on the support cylinder 7321, the cylinder mouth of the compression cylinder 7323 is opposite to the cylinder mouth of the support cylinder 7321, support springs 7324 are arranged inside the compression cylinder 7323 and the support cylinder 7321, and a pair of guide columns 7325 are arranged outside the compression cylinder 7323, and the guide columns 7325 are slidably matched with the guide opening 7326 arranged on the support cylinder 7321. Among them, the minimum combined length of the compression cylinder 7323 and the support cylinder 7321 is equal to the center distance from the positioning cylinder 7322 to the cone cylinder 731, so after the compression cylinder 7323 is compressed into the support cylinder 7321, the cone cylinder 731 can be installed in the designed direction, and after the support cylinder 7321 and the positioning cylinder 7322 are aligned, the compression cylinder 7323 is released, and the compression cylinder 7323 is lifted by the support spring 7324, so that the compression cylinder 7323 is supported in the positioning cylinder 7322. Moreover, after all the compression cylinders 7323 and the support springs 7324 are assembled in place, the coaxiality of the cone cylinder 731 and the breathing Venturi tube 72 can be effectively guaranteed, and the support spring 7324 can prevent the cone cylinder 731 and the breathing Venturi tube 72 from having a large diameter jump.

[0038] In order to improve the utilization rate of the elastic filter assembly 75, the elastic filter assembly 75 provided by the present invention includes an inner trough body 751 and an outer trough body 752 which are nested with each other. The opposite surfaces of the inner trough body 751 and the outer trough body 752 are provided with large circular openings for air flow to pass through. A plurality of stacked metal filter meshes 753 are arranged between the inner trough body 751 and the outer trough body 752. The use of stacked metal filter meshes 753 makes the elastic filter assembly 75 have a certain elasticity, can adapt to the dynamic changes of pressure in the cross breathing flow component 7, and is beneficial to improving its real-time filtering performance; a single scrapped metal filter mesh 753 can be replaced individually, thereby ensuring the comprehensive utilization rate of the elastic filter assembly 75.

[0039] In order to prevent the eddy current generated at the elbow 6 from blocking the dust from entering the downflow pipe 5, the present invention is provided with a flow block 9 at the inner top of the elbow 6, and the end of the flow block 9 facing the transition flue 81 is a crescent-shaped surface, and the thickness of the flow block 9 gradually decreases from the crescent-shaped surface to the other end of the flow block 9, and the side of the inner bottom surface of the flow block 9 facing the elbow 6 is a cylindrical surface. Among them, the crescent-shaped surface can increase the number of collisions of smoke and dust in the transition flue 81, which is conducive to its entry into the elbow 6 and the downflow pipe 5 with the flowing smoke. Furthermore, after the smoke is picked up from the end surface of the transition flue 81, it enters the elbow 6 from below the cylindrical surface, and completes a part of the pressure release in the elbow 6 part, so that part of the smoke in the elbow 6 can effectively enter the downflow pipe 5, reducing the area of ​​the eddy current, thereby reducing the resistance to the smoke and dust continuing to flow forward, and the smoke and dust will not be retained for a long time on the section between the flow block 9 and the elbow 6.

[0040] In the present invention, a vertical slider 87 is provided on the inner wall of the dust collecting cylinder 84, and a slide groove 88 which frictionally cooperates with the slider 87 is provided on the side of the suction cylinder 86. This can increase the pressure direction of the suction cylinder 86 and the dust collecting cylinder 84, which is beneficial to improving the plug-in reliability of the suction cylinder 86 and the dust collecting cylinder 84 and avoiding free movement up and down.

[0041] In order to improve the dust removal effect of the device, the present invention specially designs the path and method for guiding and removing the dust accumulated in the pre-dust removal component 8. For example, the pre-dust removal component 8 provided by the present invention is connected to the upstream pipe 4 through an air flotation component, and the upstream pipe 4 is provided with a plug valve 102 for adjusting the flow of the air flotation component.

[0042] Specifically, the dust collecting cylinder 84 of the present invention is an n-type structure, and the number of the suction cylinders 86 is two and they are respectively matched with the two branches of the dust collecting cylinder 84. Matching this, the air flotation assembly provided by the present invention includes two spatial three-dimensional Z-shaped tubes 101 connected to the bottoms of the two suction cylinders 86 in a one-to-one correspondence, and the spatial three-dimensional Z-shaped tubes 101 include multiple vertical sections and oblique sections. The two spatial three-dimensional Z-shaped tubes 101 are merged after their paths are led out of the suction cylinder 86, and the diameter of the spatial three-dimensional Z-shaped tube 101 is smaller than 1 / 2 of the diameter of the suction cylinder 86. In this case, since there is flowing flue gas in the upstream pipe 4, part of the flow in the flue gas can enter the exhaust tube 86 through the spatial three-dimensional Z-shaped tube 101, so that the dust in the dust collecting tube 84 is in an air-floating state, which is conducive to the flue gas carrying the dust to the bag dust collector 1 behind; moreover, after the dust collecting tube 84 adopts a split-tube design, the flow of the spatial three-dimensional Z-shaped tube 101 matched therewith does not need to be too large, and a moderate specification can stir up the smoke in the dust collecting tube 84, thereby ensuring the flow performance and treatment effect of the smoke on the entire dust removal path.

[0043] Furthermore, the smoke accumulated in the dust collecting tube 84 can also be introduced into the bag filter 1 from the three-dimensional Z-shaped tube 101. The plug valve 102 provided in the air flotation assembly is used to control the flow rate of the gas in the three-dimensional Z-shaped tube 101. Specifically, the plug valve 102 includes a double-headed flange tube 1021, and a bevel joint tube 1022 connected to the three-dimensional Z-shaped tube 101 is provided on the tube side of the double-headed flange tube 1021. The vertical section of the bevel joint tube 1022 is trapezoidal, and a valve cylinder 1023 is provided inside the double-headed flange tube 1021. The tube mouth of the valve cylinder 1023 faces downward and a plurality of valve ports 1024 with different calibers are provided on its side. The valve port 1024 is used to connect the bevel joint tube 1022. By rotating the valve cylinder 1023 to connect the valve ports 1024 of different diameters with the oblique joint pipe 1022 and the three-dimensional Z-shaped pipe 101, the pumping cylinder 86 can establish different connecting cross sections with the upstream pipe 4. If the connecting cross section is in a smaller specification, the gas in the three-dimensional Z-shaped pipe 101 is injected into the bag filter 1 by the air pressure in the Y-shaped dust removal inlet pipe 3, thereby realizing dust collection. The driving force of the valve cylinder 1023 can be manual or driven by an electric motor.

[0044] In order to facilitate the overall arrangement of the air flotation assembly, the present invention is provided with a hoop 103 on the side of the downflow pipe 5, which simultaneously connects the downflow pipe 5 and the vertical section of the spatial three-dimensional Z-shaped pipe 101, so that the space utilization rate of the air flotation assembly can be improved, especially the stability and safety of the air after installation at a high altitude.

[0045] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A dust removal device for flue gas in a flue of an alumina production line roasting furnace, comprising a bag dust collector and a dust removal fan, wherein a Y-shaped dust removal air inlet pipe is arranged on the top of the bag dust collector, an upflow pipe and a downflow pipe forming a U-shaped conveying path are arranged on the input side of the Y-shaped dust removal air inlet pipe, an elbow is arranged on the top of the downflow pipe, and the input side of the elbow is used to connect the roasting furnace, characterized in that: The input side of the elbow is provided with a cross breathing flow component and a pre-dust removal component connected front and back, the cross breathing flow component includes an axial flow venturi tube and a breathing venturi tube connected to the axial flow venturi tube in a cross manner, the cross connection node between the axial flow venturi tube and the breathing venturi tube is located at the center position of the two, one end of the axial flow venturi tube is connected to the roasting furnace and the other end is connected to the pre-dust removal component, a conical one-way valve assembly is provided inside the breathing venturi tube, the end of the breathing venturi tube is provided with a cap barrel connected to its flange, the end of the cap barrel is provided with an annular end cover, and the end An elastic filter assembly is arranged between the cover and the cap tube; the pre-dust removal component includes a transition flue connecting the axial flow Venturi tube and the elbow front and rear, the transition flue is a two-level stepped structure and the tube diameter at the end facing the axial flow Venturi tube is larger than the tube diameter at the end facing the elbow, a plurality of through openings distributed in the lower half of the transition flue are arranged at the stepped transition position, a dust removal jacket is arranged on the outside of the transition flue, a dust collection barrel is arranged at the bottom of the dust removal jacket, a dust collection port is arranged at the position of the dust collection barrel corresponding to the through opening, and a suction barrel telescopically matched with the dust collection barrel is arranged at the bottom of the dust collection barrel.

2. The dust removal equipment for flue gas of the alumina production line roasting furnace according to claim 1 is characterized in that: The conical one-way valve assembly includes a conical cylinder, a quick-retractable support connected to the breathing venturi is arranged on the outer side of the conical cylinder, the end of the conical cylinder facing the center of the cross breathing flow component is an open structure, the other end of the conical cylinder is provided with a bowl-shaped valve core elastically matched therewith, a valve stem is arranged in the center of the bowl-shaped valve core, the valve stem is movably matched with the telescopic opening arranged on the conical cylinder, a balancing spring is sleeved on the valve stem, the balancing spring is located inside the conical cylinder, the end of the balancing spring is provided with a limit plate and a stop nut connected to the valve stem, and the end of the bowl-shaped valve core facing away from the conical cylinder is movably matched with the conical valve plate arranged on the cap tube.

3. The dust removal equipment for flue gas of the alumina production line roasting furnace according to claim 2 is characterized in that: The rapid telescopic support member includes three supporting cylinders evenly distributed on the conical cylinder, three positioning cylinders corresponding to the supporting cylinders are arranged on the inner wall of the respiratory venturi, a compression cylinder nested with the positioning cylinder is arranged on the supporting cylinder, the cylinder mouth of the compression cylinder is opposite to the cylinder mouth of the supporting cylinder, support springs are arranged inside the compression cylinder and the supporting cylinder, a pair of guide columns are arranged outside the compression cylinder, and the guide columns are slidably matched with the guide openings arranged on the supporting cylinder.

4. The dust removal equipment for flue gas of the alumina production line roasting furnace according to claim 3 is characterized in that: The elastic filter assembly comprises an inner tank body and an outer tank body which are nested with each other, and a plurality of metal filter screens which are stacked in layers are arranged between the inner tank body and the outer tank body.

5. The dust removal equipment for flue gas of the alumina production line roasting furnace according to claim 1, characterized in that: A diverter block is provided at the inner top of the elbow, and one end of the diverter block facing the transition flue is a crescent-shaped surface. The thickness of the diverter block gradually decreases from the crescent-shaped surface to the other end of the diverter block, and the side of the diverter block facing the inner bottom surface of the elbow is a cylindrical curved surface.

6. The dust removal equipment for flue gas of the alumina production line roasting furnace according to claim 1, characterized in that: The dust collecting cylinder is an n-type structure, the number of the extraction cylinders is two and they respectively cooperate with the two branches of the dust collecting cylinder, a vertical slider is arranged on the inner wall of the dust collecting cylinder, and a slide groove which frictionally cooperates with the slider is arranged on the side of the extraction cylinder.

7. The dust removal equipment for flue gas of the alumina production line roasting furnace according to claim 6, characterized in that: The pre-dust removal component is communicated with the upstream pipe through an air flotation component, and a plug valve for adjusting the flow of the air flotation component is arranged on the upstream pipe.

8. The dust removal equipment for flue gas of the alumina production line roasting furnace according to claim 7, characterized in that: The air flotation assembly includes two spatial three-dimensional Z-shaped tubes connected to the bottoms of two pumping cylinders, the spatial three-dimensional Z-shaped tubes include multiple vertical sections and oblique sections, and the diameter of the spatial three-dimensional Z-shaped tubes is smaller than 1 / 2 of the diameter of the pumping cylinders.

9. The dust removal equipment for flue gas of the alumina production line roasting furnace according to claim 8, characterized in that: The plug valve includes a double-headed flange pipe, a bevel joint pipe connected to the spatial three-dimensional Z-shaped pipe is arranged on the pipe side of the double-headed flange pipe, the vertical section of the bevel joint pipe is trapezoidal, a valve cylinder is arranged inside the double-headed flange pipe, the mouth of the valve cylinder faces downward and a plurality of valve openings of different calibers are arranged on its side, and the valve openings are used to connect the bevel joint pipe.

10. The dust removal equipment for flue gas of the alumina production line roasting furnace according to claim 9, characterized in that: A hoop member for connecting the downflow pipe and the vertical section of the spatial three-dimensional Z-shaped pipe is arranged on the side surface of the downflow pipe.

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