Powder conveying device with variable Venturi pipe diameter

Abstract

The invention relates to the technical field of powder pneumatic conveying, and discloses a powder conveying device with a variable Venturi pipe diameter, which comprises an air inlet pipe, a Venturi injection pipe, a flow injection pipe, a throat pipe and a diffusion pipe which are sequentially arranged from left to right, the Venturi injection pipe is integrally formed by a round straight pipe, a reducer and a nozzle, the round straight pipe extends into a receiving chamber of the flow injection pipe, the nozzle falls on the lower left portion of a powder falling pipe connected with the top wall of the flow injection pipe, the left side and the right side of the throat pipe are connected with a reducing pipe and a diffusion pipe of the flow injection pipe respectively in a sealed mode, and symmetrically-distributed contracting and expanding assemblies are assembled on the upper side and the lower side of the nozzle of the Venturi injection pipe. Compared with the prior art, delay of production time is effectively avoided, under the condition that shutdown is not allowed under the working condition, the Venturi injection pipe shows excellent flexibility, the air flow can be flexibly adjusted according to the actual requirement, unnecessary energy consumption is reduced, and dust is effectively prevented from being attached to the interior of the pipe body.

Description

Technical Field

[0001] The present invention relates to the technical field of powder pneumatic conveying, and more specifically to a powder conveying device with a variable venturi tube diameter. Background Art

[0002] Pneumatic conveying, also known as air flow conveying, uses the energy of air flow to convey granular materials along the direction of air flow in a closed pipe. It is a specific application of fluidization technology. Among them, Venturi ejector is a type of pneumatic conveying equipment. Venturi ejector uses positive pressure air generated by a blower to flow through the ejector. When the flow area suddenly decreases, negative pressure is formed, and suction is generated to suck away the material above the ejector, and enable it to convey powder, particles and bulk materials in the negative pressure pneumatic conveying system.

[0003] In the process of industrial application of existing Venturi ejectors, as the nozzle diameter becomes smaller, the turbulent kinetic energy and turbulent dissipation efficiency at the same position become stronger. Therefore, in theory, the smaller the nozzle diameter, the better the mixing effect of the working fluid and the ejected fluid. However, a nozzle diameter that is too small will cause a narrow cross-section of the fluid, generate huge turbulence, and produce impact force and shear stress on the reactor wall. Long-term high-speed flow will cause wear on the vessel wall. Therefore, under different working conditions, the optimal value of the nozzle diameter suitable for industrial applications will also change, and then the nozzle needs to be replaced according to actual needs. For example, patent 202220563092.4 discloses a Venturi ejector device structure with adjustable nozzle diameter, which can replace Venturi ejectors with different nozzle diameters, and seek the nozzle diameter that is most suitable for practical applications, thereby maintaining a good mixing effect of the Venturi ejector and making the Venturi ejector have a longer service life. However, the nozzle diameter is changed only by stopping the machine, disassembling it, and then replacing different nozzle components, which is cumbersome to operate and affects production. Summary of the invention

[0004] In order to overcome the above-mentioned defects of the prior art, the present invention provides a powder conveying device with a variable Venturi tube diameter to solve the problem that the nozzle diameter in the existing Venturi injector cannot be adjusted according to changes in working conditions, resulting in a constant negative pressure in the Venturi injector, which causes poor conveying effect when the working conditions change, thereby affecting the conveying efficiency.

[0005] The present invention provides the following technical solutions: a powder conveying device with a variable venturi tube diameter, comprising an air intake pipe, a venturi injection pipe, a jet tube, a throat pipe and a diffuser pipe arranged in sequence from left to right, the air intake pipe and the venturi injection pipe are connected by a flange, the venturi injection pipe is formed by a round straight pipe, a large and small head and a nozzle, the round straight pipe extends into the receiving chamber of the jet tube, and the nozzle falls on the lower left of the powder falling pipe connected to the top wall of the jet tube, the left and right sides of the throat pipe are respectively sealed and connected to the convergent pipe and the diffuser of the jet tube, the upper and lower sides of the nozzle of the venturi injection pipe are equipped with symmetrically distributed expansion and contraction components, and the periphery of the venturi injection pipe on the same side is provided with a recursive bar capable of expanding and contracting the caliber of the expansion and contraction component, a driving component for driving the recursive bar to move is provided between the jet tube and the venturi injection pipe, and a maintenance component that can be extended into the throat pipe is provided in the convergent pipe of the jet tube; The nozzle of the venturi injection pipe is provided with an arc-shaped opening which is symmetrically distributed up and down, and a contraction and expansion component is arranged outside the arc-shaped opening, and the contraction and expansion component includes a conical cover, and the conical cover is sealed and covered on the periphery of the arc-shaped opening, and a spliced ​​guide tube which is fitted in sequence is nested in the conical cover, and the spliced ​​guide tube is a 1 / 2 conical tube, and the caliber of the connection between the two adjacent spliced ​​guide tubes on the left and right is equal, and the two spliced ​​guide tubes on the same side above and below can be aggregated into a complete conical tube and be concentric with the nozzle of the venturi injection pipe, and the aggregated multiple conical tubes are spliced ​​in sequence into a conical channel with decreasing caliber, and the top of each spliced ​​guide tube is fixedly connected with a plug-in block which can pass through the conical cover, and the front and rear sides of the plug-in block are provided with symmetrically distributed rebound parts.

[0006] Furthermore, the caliber of the left end of the leftmost spliced ​​guide pipe should be equal to the caliber of the rightmost end of the reducer, and the caliber of the right end of the rightmost spliced ​​guide pipe is the set minimum caliber.

[0007] Furthermore, the left and right longitudinal sections of the plug-in block are conical, and the left and right sides are outwardly inclined surfaces. A slide groove is arranged in the middle. The surface of the conical cover is provided with perforations for the plug-in block to be telescopically moved up and down. The cross-section of the perforations is arranged so that at least the plug-in block can carry the spliced ​​guide tube attached to the inner wall of the conical cover. An elastic sealing ring is arranged at the perforation of the conical cover to seal the movable plug-in block, and the elastic sealing ring is embedded in the slide groove.

[0008] Furthermore, the rebound member includes a pressure plate, a slide plate, a column, a first spring and a fixing frame, wherein the pressure plate and the slide plate are respectively arranged at the top and bottom of the outer side of the plug-in block, the pressure plate is fixedly connected to the plug-in block, the slide plate is slidably engaged in the slide groove of the plug-in block, the bottom end of the column is fixedly connected to the slide plate, and the top end thereof is movably connected to the pressure plate, and a first spring connected between the pressure plate and the slide plate is arranged on the periphery of the column, and the slide plate can be installed on the outer wall of the conical cover through the fixing frame.

[0009] Furthermore, the end face of the recursive bar is provided with an inclined push groove, which matches the outward inclined surface of the side wall of the plug-in block. The upper and lower outer walls of the Venturi injection tube are fixedly connected with guide rails. The recursive bar is slidably clamped above the guide rails and can only move horizontally along the guide rails.

[0010] Furthermore, the maintenance assembly includes a bucket body, a cleaning tube, a gear ring, a limit ring and an elastic telescopic rod, wherein the bucket body and the cleaning tube are respectively arranged in the tapered tube and the throat of the jet tube, the gear ring is located in the receiving chamber of the jet tube, the gear ring, the bucket body and the cleaning tube are fixed in sequence by connecting rods, the gear ring is rotatably clamped on the left side of the limit ring, the limit ring is connected to the telescopic end of the elastic telescopic rod, and the elastic telescopic rod is detachably installed in the receiving chamber.

[0011] Furthermore, the bristles of the cleaning tube of the bucket body can touch the inner wall of the reducer and the throat respectively, the outer contour of the bucket body is adapted to the end of the reducer, the bucket body can move and fit on the end of the reducer of the jet tube, the diameter of the right end of the bucket body is equal to the diameter of the cleaning tube, and is consistent with the maximum diameter of the nozzle.

[0012] Furthermore, the driving assembly includes a transmission shaft, a driven shaft, a bevel gear set, a plane gear and a power unit, wherein the two ends of the transmission shaft are connected to the upper and lower driven shafts through a bevel gear set, and the ends of the upper and lower driven shafts away from the transmission shaft are fixedly sleeved with plane gears, and the plane gears are meshed with recursive bars for transmission, and the transmission shaft and the driven shaft are limited in a predetermined position by a positioning frame installed on the Venturi injection tube, and the transmission shaft receives the driving force from the power unit.

[0013] Furthermore, flanges are provided at the end faces of the Venturi injection tube and the air inlet pipe that are close to each other, and the two are detachably connected via the flanges. A space is reserved between the Venturi injection tube and the jet tube for movement of the expansion and retraction assembly, the recursive bar and the driving assembly. A side baffle that can seal and combine the two is detachably installed between the round straight tube of the Venturi injection tube and the end face of the receiving chamber of the jet tube.

[0014] Furthermore, the top end of the powder drop pipe is connected to the supply source of the desulfurizer, and the bottom end of the powder drop pipe is connected to the receiving chamber of the jet tube. The end of the receiving chamber away from the Venturi injection tube is a convergent tube. The receiving chamber and the convergent tube are integrally formed, and the connection method between the two ends of the throat and the contact surface of the convergent tube and the diffuser tube adopts a welding process.

[0015] Technical effects and advantages of the present invention: The present invention is provided with a recursive strip, a collection and expansion component and a driving component. The venturi injection tube has an innovative design, which greatly optimizes the nozzle replacement process, so that the nozzle can be quickly replaced without disassembling it. This feature ensures that the replacement operation can be successfully completed while production is ongoing, thereby effectively avoiding delays in production time. When the working conditions do not allow shutdown, the venturi injection tube shows its excellent flexibility and can flexibly adjust the air flow according to actual needs. This function not only reduces unnecessary energy consumption, but also effectively prevents dust from adhering to the tube body, thereby maintaining the cleanliness and efficient operation of the equipment. More advanced is that the design also takes into account the protection of the tapered tube. Through the flexible shape-changing structure, the risk of the tapered tube being damaged by airflow impact is reduced. In addition, the venturi injection tube with an adjustable nozzle adopts advanced sealing technology to ensure excellent sealing performance. This feature further improves the overall use effect of the venturi injector and brings users a more stable and reliable production experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0017] Figure 2 It is a schematic diagram of the overall structure of the present invention and its partial cross-section.

[0018] Figure 3 It is a schematic diagram of the connection structure of the venturi injection tube, the jet tube, the expansion and contraction assembly, the recursion bar and the driving assembly of the present invention.

[0019] Figure 4 It is a schematic diagram of the connection structure of the venturi injection tube, the expansion assembly, the recursive bar, the guide rail and the driving assembly of the present invention.

[0020] Figure 5 It is a schematic diagram of the connection structure of the venturi injection tube, guide rail, recursive bar and drive assembly of the present invention.

[0021] Figure 6 It is a schematic diagram of the structure of the power unit of the present invention.

[0022] Figure 7 It is a schematic diagram of the connection structure of the venturi injection tube, the expansion and contraction assembly, the recursive bar and the guide rail of the present invention.

[0023] Figure 8 For the present invention Figure 7 Schematic diagram of the structure at point A in the middle.

[0024] Fig. 9 It is a schematic diagram of the connection structure of the plug-in block, the rebound member and the recursive bar of the present invention.

[0025] Fig.10It is a schematic diagram of the connection structure of the jet pipe, throat pipe and maintenance assembly of the present invention.

[0026] Fig.11 It is a schematic diagram of the connection structure of the bucket body, cleaning cylinder, gear ring and limit ring of the present invention.

[0027] The accompanying drawings are marked as follows: 1. air intake pipe; 2. venturi jet pipe; 3. jet pipe; 4. powder drop pipe; 5. throat pipe; 6. diffuser; 7. expansion and contraction assembly; 701. conical cover; 702. splicing guide pipe; 703. plug-in block; 704. rebound member; 7041. pressure plate; 7042. slide plate; 7043. column; 7044. first spring; 7045. fixing frame; 705. elastic sealing ring; 8. recursive strip; 9. drive assembly; 901. transmission shaft; 902. driven shaft; 903. bevel gear Group; 904, flat gear; 905, power unit; 9051, first motor; 9052, worm; 9053, vortex gear group; 9054, driven gear; 906, positioning frame; 10, maintenance assembly; 1001, bucket body; 1002, cleaning cylinder; 1003, gear ring; 1004, limit ring; 1005, elastic telescopic rod; 10051, barrel; 10052, piston rod; 10053, second spring; 1006, driving gear; 1007, second motor; 11, guide rail. DETAILED DESCRIPTION

[0028] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the present invention. In addition, the forms of the various structures recorded in the following embodiments are merely illustrative. The powder conveying device with a variable venturi tube diameter involved in the present invention is not limited to the various structures recorded in the following embodiments. All other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0029] Reference Figure 1-11 The present invention provides a powder conveying device with a variable venturi tube diameter, comprising an air intake pipe 1, a venturi injection pipe 2, a jet tube 3, a throat pipe 5 and a diffuser 6 which are arranged in sequence from left to right, the air intake pipe 1 and the venturi injection pipe 2 are connected by a flange, the venturi injection pipe 2 is integrally formed by a round straight pipe, a large and small head and a nozzle, the round straight pipe extends into the receiving chamber of the jet tube 3, and the nozzle falls on the lower left side of the powder falling pipe 4 connected to the top wall of the jet tube 3, the left and right sides of the throat pipe 5 are respectively sealed and connected to the convergent pipe and the diffuser 6 of the jet tube 3, the upper and lower sides of the nozzle of the venturi injection pipe 2 are equipped with symmetrically distributed expansion and contraction components 7, and the periphery of the venturi injection pipe 2 on the same side is provided with a recursive bar 8 which can expand and contract the caliber of the expansion and contraction component 7, a driving component 9 which can drive the recursive bar 8 to move is arranged between the jet tube 3 and the venturi injection pipe 2, and a maintenance component 10 which can extend into the throat pipe 5 is arranged in the convergent pipe of the jet tube 3.

[0030] In this embodiment, it should be specifically explained that the end of the air inlet pipe 1 away from the Venturi injection pipe 2 is connected to the Roots blower, and the gas flow blown out by the Roots blower is introduced into the Venturi injection pipe 2 through the air inlet pipe 1, and after passing through the round straight pipe of the Venturi injection pipe 2, it enters the reducer and reducer, and then enters the nozzle. The gas flow cross-section at the nozzle is sharply reduced, so that the gas is accelerated to form a high-speed airflow, and the static pressure energy is converted into dynamic pressure energy, resulting in a negative pressure adsorption effect. At this time, the granular powder is introduced into the flow injection pipe 3 from the powder falling pipe 4, is adsorbed by the negative pressure gas and transported to the target position along with the high-speed airflow; The end faces of the Venturi injection tube 2 and the air inlet pipe 1 that are close to each other are both provided with flanges, and the two are detachably connected through the flanges. A space is reserved between the Venturi injection tube 2 and the jet tube 3 for movement of the retracting and expanding assembly 7, the recursive bar 8 and the driving assembly 9 to avoid movement interference. A side baffle that can seal and combine the two can be detachably installed between the round straight tube of the Venturi injection tube 2 and the end face of the receiving chamber of the jet tube 3. When the Venturi injection tube 2 or the parts installed thereon need to be repaired, the flange and the side baffle can be disassembled to remove the Venturi injection tube 2 from the jet tube 3, so as to facilitate its maintenance or replacement. The top of the powder drop pipe 4 is connected to a supply source of the desulfurizer, such as a material box for storing the desulfurizer, and the bottom of the powder drop pipe 4 is connected to the receiving chamber of the jet tube 3. The end of the receiving chamber away from the venturi injection tube 2 is a convergent tube. The receiving chamber and the convergent tube are integrally formed. The connection method of the two ends of the throat 5 and the contact surface of the convergent tube and the diffuser 6 can adopt a welding process; the diffuser 6 can transport the desulfurizer to the target position by means of high-speed airflow to mix with the sulfur-containing gas in the flue; The sulfur monitoring module in the flue detects that the sulfur content is abnormally increased. When the sulfur monitoring module in the flue (using laser spectroscopy or electrochemical sensor) detects that the sulfur oxide (SOx) content exceeds the preset threshold, the real-time data will be uploaded to the DCS control system through a 4-20mA analog signal or MODBUS communication protocol. The control system dynamically adjusts the dosage of the desulfurizer (such as limestone slurry) in the drop pipe based on the PID algorithm. The adjustment amount is calculated by the following formula: Q=K×(S measured-S set) / τ, where Q is the adjustment flow, K is the proportional coefficient, and τ is the response time constant; In this article, all the positional relationships we discuss about front, back, left, and right are based on Figure 1-2 These directions are defined by the perspective presented. They have no actual geographical or physical meaning. They are merely a reference framework set to help readers understand the content of the article more intuitively. In this way, we can more clearly show the relative position relationship between the various parts, making the entire discussion process easier to understand and follow. Please note that this custom direction mark is only for internal use in this article and does not represent any absolute direction or position in the real world.

[0031] Reference Figure 3-9 The nozzle of the venturi injection tube 2 is provided with an arc-shaped opening symmetrically distributed up and down, and a receiving and expanding component 7 is arranged outside the arc-shaped opening. The receiving and expanding component 7 includes a conical cover 701, and the conical cover 701 is sealed and covered on the periphery of the arc-shaped opening. A plurality of spliced ​​guide tubes 702 are nested in the conical cover 701 and are sequentially fitted. The spliced ​​guide tubes 702 are 1 / 2 cone tubes. The number of spliced ​​guide tubes 702 can be flexibly set according to the specific situation, but the diameter of the left end of the next spliced ​​guide tube 702 must be equal to the diameter of the right end of the previous spliced ​​guide tube 702, that is, The calibers of the joints of the two adjacent spliced ​​guide pipes 702 on the left and right are equal. The two spliced ​​guide pipes 702 on the upper and lower sides can be aggregated into a complete cone tube and be concentric with the nozzle of the venturi injection pipe 2. The aggregated multiple cone tubes are sequentially spliced ​​into a cone-shaped channel with decreasing calibers. The top of each spliced ​​guide pipe 702 is fixedly connected to a plug-in block 703 that can pass through the conical cover 701. The front and rear sides of the plug-in block 703 are provided with symmetrically distributed resilient parts 704, so that the plug-in block 703 can carry the spliced ​​guide pipe 702 to reciprocate in the vertical direction. The driving assembly 9 includes a transmission shaft 901, a driven shaft 902, a bevel gear set 903, a flat gear 904 and a power unit 905, wherein both ends of the transmission shaft 901 are connected to the upper and lower driven shafts 902 through the bevel gear set 903, and the ends of the upper and lower driven shafts 902 away from the transmission shaft 901 are fixedly sleeved with flat gears 904, and the flat gears 904 are meshed with the recursive bar 8 for transmission. The transmission shaft 901 and the driven shaft 902 are limited in a predetermined position by a positioning frame 906 installed on the Venturi injection tube 2, and the transmission shaft 901 receives the driving force from the power unit 905.

[0032] In this embodiment, it should be specifically explained that the caliber of the left end of the leftmost spliced ​​guide tube 702 should be equal to the caliber of the rightmost end of the reducer, and the caliber of the right end of the rightmost spliced ​​guide tube 702 is the minimum caliber to be set, and the caliber size actually determines the minimum exhaust area of ​​the nozzle and the maximum flow rate of the gas exhaust; The left and right longitudinal sections of the plug-in block 703 are conical, and the left and right sides thereof are outwardly inclined surfaces, and a slide groove is arranged in the middle. The surface of the conical cover 701 is provided with a perforation for the plug-in block 703 to move up and down, and the cross-section of the perforation is set to at least enable the plug-in block 703 to carry the spliced ​​guide tube 702 and attach to the inner wall of the conical cover 701. The perforation of the conical cover 701 is provided with an elastic sealing ring 705 for sealing the movable plug-in block 703, and the elastic sealing ring 705 is embedded in the slide groove. With the strong elastic property of the elastic sealing ring 705, even if the plug-in block 703 moves downward, the elastic sealing ring 705 can continuously tighten it to ensure the sealing ability; The resilient member 704 includes a pressing plate 7041, a slide plate 7042, a column 7043, a first spring 7044 and a fixing frame 7045, wherein the pressing plate 7041 and the slide plate 7042 are respectively arranged at the top and bottom of the outer side of the plug-in block 703, the pressing plate 7041 is fixedly connected to the plug-in block 703, the slide plate 7042 is slidably engaged in the slide groove of the plug-in block 703, the bottom end of the column 7043 is fixedly connected to the slide plate 7042, and the top end thereof is movably connected to the pressing plate 7041, and the outer periphery of the column 7043 is provided with a spring connected to the plug-in block 703. The first spring 7044 between the pressure plate 7041 and the slide plate 7042 can be installed on the outer wall of the conical cover 701 through the fixing frame 7045, so that the slide plate 7042 is relatively fixed, so that when the plug-in block 703 is pushed downward, the pressure plate 7041 connected to the top of the plug-in block 703 can slide down along the surface of the column 7043 and continuously compress the first spring 7044, so that the first spring 7044 accumulates force, so that it can be reset in time when the external force of the plug-in block 703 is removed; The end face of the recursive bar 8 is provided with an oblique push groove, which is matched with the outwardly inclined surface of the side wall of the plug-in block 703. The upper and lower outer walls of the venturi injection tube 2 are fixedly connected with the guide rail 11. The recursive bar 8 is slidably clamped above the guide rail 11 and can only move horizontally along the guide rail 11. When the recursive bar 8 is pushed by the transmission force, the oblique push groove on the end face of the recursive bar 8 can squeeze the outwardly inclined surface of the side wall of the plug-in block 703, so that the plug-in block 703 is pushed downward, so that the plug-in block 703 carries the spliced ​​guide pipe 702 at its bottom end to aggregate into a cone tube; The power unit 905 includes a first motor 9051, a worm 9052, a vortex gear set 9053 and a driven gear 9054, wherein the output shaft of the first motor 9051 is assembled with the worm 9052, the vortex gear set 9053 is located next to the worm 9052, the vortex gear set 9053 is meshed with the driven gear 9054, and the driven gear 9054 is fixedly connected with the transmission shaft 901, so that the output torque of the first motor 9051 is transmitted to the vortex gear set 9053 through the worm 9052, and then the driven gear 9054 and the transmission shaft 901 are driven by the vortex gear set 9053 to rotate as a whole; the worm 9052, the vortex gear set 9053 and the driven gear 9054 are installed in the casing, and the first motor 9051 is installed outside the Venturi injection tube 2.

[0033] Reference Figure 10-11The maintenance assembly 10 includes a bucket body 1001, a cleaning tube 1002, a gear ring 1003, a limit ring 1004 and an elastic telescopic rod 1005, wherein the bucket body 1001 and the cleaning tube 1002 are respectively arranged in the tapered tube and the throat 5 of the jet tube 3, the gear ring 1003 is located in the receiving chamber of the jet tube 3, the gear ring 1003, the bucket body 1001 and the cleaning tube 1002 are fixed in sequence by connecting rods, the gear ring 1003 is rotatably clamped on the left side of the limit ring 1004, the limit ring 1004 is connected to the telescopic end of the elastic telescopic rod 1005, and the elastic telescopic rod 1005 is detachably installed in the receiving chamber; The bristles of the cleaning tube 1002 of the bucket body 1001 can touch the inner wall of the reducer and the throat 5 respectively. The outer contour of the bucket body 1001 is adapted to the end of the reducer. The bucket body 1001 can move and fit on the end of the reducer of the jet tube 3. The diameter of the right end of the bucket body 1001 is equal to the diameter of the cleaning tube 1002 and is consistent with the maximum diameter of the nozzle.

[0034] In this embodiment, it should be specifically explained that the maintenance component 10 also includes a driving gear 1006 and a second motor 1007, wherein the driving gear 1006 is arranged on the periphery of the gear ring 1003 and meshes therewith, the driving gear 1006 is fixedly connected to the output shaft of the second motor 1007, and the second motor 1007 is installed on the limit ring 1004; when the bucket body 1001 is not in contact with the end of the tapered tube, the second motor 1007 is responsible for carrying the driving gear 1006 to drive the gear ring 1003, so that the bucket body 1001 and the cleaning cylinder 1002 rotate coaxially to clean the inner wall of the tapered tube and the throat 5, and when the bucket body 1001 is in contact with the end of the tapered tube, the second motor 1007 stops driving, and the stationary bucket body 1001 protects the tapered tube; The elastic telescopic rod 1005 includes a barrel 10051 , a piston rod 10052 and a second spring 10053 , wherein one end of the piston rod 10052 is fixedly connected to the limit ring 1004 , and the other end of the piston rod 10052 is connected to the second spring 10053 in the barrel 10051 .

[0035] Working principle of the present invention: The gas blown out by the Roots blower flows through the round straight tube of the Venturi injection tube 2, enters the reducer and then enters the nozzle. At the nozzle, due to the sharp reduction of the gas flow cross-section, the gas is accelerated to form a high-speed airflow, and the static pressure energy is converted into dynamic pressure energy, thereby generating a negative pressure area around the gas, forming a negative pressure adsorption effect. At this time, the granular powder is introduced into the receiving chamber of the jet tube 3 by the powder drop tube 4, adsorbed by the negative pressure gas and transported to the target position with the high-speed airflow. When the sulfur monitoring module in the flue detects an abnormal increase in sulfur content, it will immediately feed back this information to the control system, and the control system will then issue a command to increase the flow rate of the desulfurizer in the drop tube to cope with the increase in sulfur content. On the other hand, in order to ensure that the gas ejected from the nozzle can fully carry away these incremental desulfurizers, the control system will also adjust the nozzle diameter of the Venturi injection tube 2. This is the nozzle diameter reduction process, thereby ensuring the smooth progress of the entire desulfurization process; The specific process of reducing the nozzle diameter is that the power unit 905 drives the transmission shaft 901 to spin, and the spinning transmission shaft 901 transmits the torque force to the upper and lower driven shafts 902 through the bevel gear set 903, so that the upper and lower driven shafts 902 respectively carry the flat gears 904 at their ends to rotate from outside to inside, and then drive the upper and lower recursive bars 8 to slide from left to right along the surface of the guide rail 11, and the inclined push groove on the end face of the recursive bar 8 will contact and squeeze the outward inclined surface of the side wall of the plug-in block 703, so that the plug-in block 703 is subjected to a downward thrust, and the pressure plate 7041 connected to the top of the plug-in block 703 can slide down along the surface of the column 7043 and continuously compress the first spring 7044. When the recursive bar 8 pushes the splicing guide connected to the bottom end of the leftmost plug-in block 703 When the tube 702 is pushed to be concentric with the nozzle, the spliced ​​guide tube 702 is aggregated into a conical tube, the left side of which is connected to the reducer and the right side is directed to the center of the nozzle, completing the first reduction of the nozzle diameter, thereby reducing the effective cross-sectional area of ​​the nozzle, so that the flow rate of the gas blown out of the Roots blower when passing through the nozzle becomes larger, and more desulfurizer can be taken away. If the desulfurizer falls faster, the recursive bar 8 continues to move forward, and approaches and presses the next section of the plug-in block 703 in the same mechanism while maintaining the previous formed conical tube from disintegrating, so that the subsequent multiple spliced ​​guide tubes 702 are successively aggregated, and the aggregated multiple conical tubes are sequentially spliced ​​into a conical channel with a gradually decreasing diameter, further reducing the effective area of ​​the nozzle, and increasing the gas flow rate to adapt to the increase in the desulfurizer content; When the recursive bar 8 completes the aggregate control of all the spliced ​​guide tubes 702, the recursive bar 8 that continues to move will push the gear ring 1003, and the gear ring 1003 transmits the thrust to the telescopic end of the elastic telescopic rod 1005 through the limit ring 1004, so that the telescopic end of the elastic telescopic rod 1005 elastically shrinks inward, and then the gear ring 1003, the bucket body 1001 and the cleaning cylinder 1002 that are sequentially combined through the connecting rod are translated to the right, so that the bucket body 1001 gradually fits at the end of the convergent tube of the jet tube 3. At the same time, the second motor 1007 is controlled to stop driving, so that the gear ring 1003 no longer carries the bucket body 1001 and the cleaning cylinder 1002 to rotate coaxially, causing the bucket body 1001 and the cleaning cylinder 1002 to switch from motion to stillness, that is, the cleaning stage of the convergent tube and the throat 5 is converted into the protection stage of the convergent tube, thereby reducing the wear of the connection between the convergent tube and the throat 5 caused by long-term high-speed flow; When the sulfur content drops and the amount of desulfurizer used decreases, the equipment can be restored by implementing the opposite steps to the above.

[0036] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent substitutions or modifications within the technical scope disclosed by the present invention; according to the technical plan and its improved conception of the present invention, all of which should be included under the protection of the present invention.

Claims

1. A powder conveying device with a variable venturi tube diameter, comprising an air inlet pipe (1), a venturi injection pipe (2), a jet pipe (3), a throat pipe (5) and a diffuser pipe (6) arranged in sequence from left to right, characterized in that: The air inlet pipe (1) and the venturi injection pipe (2) are connected via a flange. The venturi injection pipe (2) is integrally formed of a round straight pipe, a large and small head and a nozzle. The round straight pipe extends into the receiving chamber of the jet pipe (3), and the nozzle falls on the lower left side of the powder drop pipe (4) connected to the top wall of the jet pipe (3). The left and right sides of the throat pipe (5) are respectively sealed and connected to the convergent pipe and the diffuser (6) of the jet pipe (3). The upper and lower sides of the nozzle of the venturi injection pipe (2) are equipped with symmetrically distributed expansion components (7), and the periphery of the venturi injection pipe (2) on the same side is provided with a recursive bar (8) capable of expanding and contracting the caliber of the expansion component (7). A driving component (9) for driving the recursive bar (8) to move is provided between the jet pipe (3) and the venturi injection pipe (2). A maintenance component (10) capable of extending into the throat pipe (5) is provided in the convergent pipe of the jet pipe (3); The nozzle of the venturi injection tube (2) is provided with an arc-shaped opening symmetrically distributed in the upper and lower parts, and a contraction and expansion assembly (7) is arranged outside the arc-shaped opening. The contraction and expansion assembly (7) comprises a conical cover (701), and the conical cover (701) is sealed and covered on the outer periphery of the arc-shaped opening. The conical cover (701) is embedded with a spliced ​​flow guide tube (702) which is fitted in sequence. The spliced ​​flow guide tube (702) is a 1 / 2 conical tube. The calibers of the joints of two adjacent spliced ​​flow guide tubes (702) on the left and right are equal. The two spliced ​​flow guide tubes (702) on the same side above and below can be aggregated into a complete conical tube and are concentric with the nozzle of the venturi injection tube (2). The aggregated multiple conical tubes are sequentially spliced ​​into a conical channel with decreasing calibers. The top of each spliced ​​flow guide tube (702) is fixedly connected to a plug-in block (703) which can pass through the conical cover (701), and the front and rear sides of the plug-in block (703) are provided with symmetrically distributed resilient parts (704).

2. The powder conveying device with variable venturi diameter according to claim 1, characterized in that: The caliber of the left end of the leftmost spliced ​​guide tube (702) should be equal to the caliber of the rightmost end of the reducer, and the caliber of the right end of the rightmost spliced ​​guide tube (702) is the set minimum caliber.

3. The powder conveying device with variable Venturi diameter according to claim 1, characterized in that: The left and right longitudinal sections of the plug-in block (703) are conical, and the left and right sides thereof are outwardly inclined surfaces, and a slide groove is arranged in the middle. The surface of the conical cover (701) is provided with a through hole for the plug-in block (703) to move up and down, and the cross section of the through hole is arranged so that at least the plug-in block (703) can carry the spliced ​​guide tube (702) attached to the inner wall of the conical cover (701). An elastic sealing ring (705) for sealing the movable plug-in block (703) is arranged at the through hole of the conical cover (701), and the elastic sealing ring (705) is embedded in the slide groove.

4. The powder conveying device with variable venturi diameter according to claim 1, characterized in that: The resilient member (704) comprises a pressing plate (7041), a sliding plate (7042), a column (7043), a first spring (7044) and a fixing frame (7045), wherein the pressing plate (7041) and the sliding plate (7042) are respectively arranged at the top and bottom of the outer side of the plug-in block (703), the pressing plate (7041) is fixedly connected to the plug-in block (703), the sliding plate (7042) is slidably engaged in the sliding groove of the plug-in block (703), the bottom end of the column (7043) is fixedly connected to the sliding plate (7042), and the top end thereof is movably sleeved with the pressing plate (7041), the outer periphery of the column (7043) is provided with a first spring (7044) connected between the pressing plate (7041) and the sliding plate (7042), and the sliding plate (7042) can be mounted on the outer wall of the conical cover (701) through the fixing frame (7045).

5. The powder conveying device with variable venturi diameter according to claim 1, characterized in that: The end surface of the recursive bar (8) is provided with an inclined push groove, which matches the outwardly inclined surface of the side wall of the plug-in block (703). The upper and lower outer walls of the Venturi injection tube (2) are fixedly connected to the guide rail (11). The recursive bar (8) is slidably engaged above the guide rail (11) and can only move horizontally along the guide rail (11).

6. The powder conveying device with variable venturi diameter according to claim 1, characterized in that: The maintenance assembly (10) comprises a bucket body (1001), a cleaning tube (1002), a gear ring (1003), a limit ring (1004) and an elastic telescopic rod (1005), wherein the bucket body (1001) and the cleaning tube (1002) are respectively arranged in the tapered tube and the throat (5) of the jet tube (3), the gear ring (1003) is located in the receiving chamber of the jet tube (3), the gear ring (1003), the bucket body (1001) and the cleaning tube (1002) are fixed in sequence by connecting rods, the gear ring (1003) is rotatably clamped on the left side of the limit ring (1004), the limit ring (1004) is connected to the telescopic end of the elastic telescopic rod (1005), and the elastic telescopic rod (1005) is detachably installed in the receiving chamber.

7. The powder conveying device with a variable venturi diameter according to claim 6, characterized in that: The bristles of the cleaning tube (1002) of the bucket body (1001) can respectively touch the inner wall of the reducer and the throat (5); the outer contour of the bucket body (1001) is adapted to the end of the reducer; the bucket body (1001) can move and fit on the end of the reducer of the jet tube (3); the diameter of the right end of the bucket body (1001) is equal to the diameter of the cleaning tube (1002) and is consistent with the maximum diameter of the nozzle.

8. The powder conveying device with variable venturi diameter according to claim 1, characterized in that: The driving assembly (9) comprises a transmission shaft (901), a driven shaft (902), a bevel gear set (903), a plane gear (904) and a power unit (905), wherein the two ends of the transmission shaft (901) are connected to the upper and lower driven shafts (902) through the bevel gear set (903), and the ends of the upper and lower driven shafts (902) away from the transmission shaft (901) are fixedly sleeved with a plane gear (904), and the plane gear (904) is meshed with a recursive bar (8) for transmission, and the transmission shaft (901) and the driven shaft (902) are limited at a predetermined position by a positioning frame (906) installed on the venturi injection pipe (2), and the transmission shaft (901) receives the driving force from the power unit (905).

9. The powder conveying device with variable venturi diameter according to claim 1, characterized in that: The end surfaces of the Venturi injection pipe (2) and the air inlet pipe (1) that are close to each other are both provided with flanges, and the two are detachably connected via the flanges. A space is left between the Venturi injection pipe (2) and the jet pipe (3) for movement of the expansion and contraction assembly (7), the recursive bar (8) and the driving assembly (9). A side baffle that can seal and combine the two is detachably installed between the round straight pipe of the Venturi injection pipe (2) and the end surface of the receiving chamber of the jet pipe (3).

10. The powder conveying device with variable venturi diameter according to claim 1, characterized in that: The top end of the powder drop pipe (4) is connected to a supply source of the desulfurizing agent, and the bottom end of the powder drop pipe (4) is connected to a receiving chamber of the jet pipe (3). The end of the receiving chamber away from the venturi jet pipe (2) is a convergent pipe, and the receiving chamber and the convergent pipe are integrally formed. The two ends of the throat pipe (5) are connected to the contact surfaces of the convergent pipe and the diffuser pipe (6) by welding.

Images