Dust airflow heat recovery equipment for zinc oxide preparation

Abstract

The invention relates to the technical field of zinc oxide preparation through a dry method, and particularly discloses dust airflow heat recovery equipment for zinc oxide preparation, which comprises an outer thermal insulation cylinder and an inner settling cylinder which are concentrically arranged, the lower end of the inner settling cylinder is connected with a collecting hopper, the lower end of the collecting hopper is connected with a settled material discharge pipe, and the upper end of the inner cavity of the outer thermal insulation cylinder is provided with a flow divider; the top end of the flow divider is connected with a dust airflow inlet pipe, the outer circumference of the flow divider is evenly connected with a plurality of flow dividing heat exchange pipes, the lower ends of the flow dividing heat exchange pipes are connected with bent spraying pipes, a dust airflow discharging pipe extending into the settled material discharging pipe is concentrically arranged in the inner settling cylinder, and a plurality of suction openings are evenly formed in the upper end of the dust airflow discharging pipe. The heat recycling effect of zinc oxide powder airflow heat can be effectively improved, full separation between zinc oxide powder and zinc oxide powder is achieved, and the quality of finally collected zinc oxide products is improved.

Description

Technical Field

[0001] The invention relates to the technical field of dry-process zinc oxide preparation, and particularly discloses dust airflow heat recovery equipment for zinc oxide preparation. Background Art

[0002] During the dry process of zinc oxide production, zinc ore is first heated to form a melt. The melt is then heated further to evaporate zinc vapor, which then oxidizes into zinc oxide powder particles upon contact with incoming air. These particles are then transported along pipelines within the plant, ultimately reaching a baghouse where they are filtered and captured, resulting in zinc oxide powder.

[0003] Existing zinc oxide production enterprises fail to fully recycle the heat of the zinc oxide powder airflow during the transportation process of the zinc oxide powder airflow through their factory pipelines, resulting in large heat loss and high temperature in the factory. In addition, the powder airflow in a high-temperature state will cause damage to the bag when in contact with the bag for a long time, thus shortening the service life of the bag collector.

[0004] The invention patent with application number 2021108840619 discloses an energy-saving and efficient oxidation equipment for zinc oxide production, including a kiln, an oxidation chamber, a collection hood and a flue gas duct. A spiral coil is fixedly connected to the inner wall of the oxidation chamber, and a plurality of air outlets are evenly opened at the lower end of the coil. The air outlets are arranged inclined upward and toward the center of the oxidation chamber. The upper end of the coil is connected to an air supply pipe, which is arranged along the central axis of the flue gas duct and the end of the air supply pipe extends out of the flue gas duct and is connected to the fan. The equipment disclosed in this invention patent designs the air supply pipe along the flue gas duct and uses the air sent into the air supply pipe to recycle the heat in the high-temperature flue gas (i.e., the zinc oxide powder airflow), which plays a role in energy conservation and emission reduction to a certain extent. However, its heat recovery effect on the high-temperature flue gas is not ideal. The main reasons are that on the one hand, the heat exchange area is small, and on the other hand, the two are transported in a straight line by convection, resulting in too short a heat exchange time and the inability to fully absorb the heat of the high-temperature flue gas. In addition, during the dry process of preparing zinc oxide powder, some zinc oxide particles with larger particle sizes may be present. Multiple sedimentation pipes are usually required to settle them, but the sedimentation effect is not ideal. As a result, the zinc oxide powder collected in the bag collector contains a small amount of large zinc oxide particles, affecting the quality of the final product. Therefore, to address the above-mentioned shortcomings of existing energy-saving and efficient oxidation equipment for zinc oxide production, this application proposes a dust airflow heat recovery device for zinc oxide production that can effectively solve the above-mentioned technical problems. Summary of the Invention

[0005] The present invention aims to provide a dust airflow heat recovery device for zinc oxide preparation, so as to solve the problems of poor heat exchange effect of zinc oxide powder airflow in the prior art and inability to effectively remove large particles of zinc oxide in the dust airflow, resulting in poor quality of the final product.

[0006] The present invention is achieved through the following technical solutions: The exhaust gas fan of the gas heating unit is connected with the exhaust gas fan of the gas heating unit, and the exhaust gas fan of the gas heating unit is connected with the exhaust gas fan of the gas heating unit. A partition ring is provided between the top of the outer circular surface of the inner settling tube and the inner wall of the outer insulation tube. A circular hole is provided on the partition ring for passing the diversion heat exchange tube. A heat exchange gas inlet is provided on the partition ring located between two adjacent circular holes. The top end of the outer insulation tube is connected to an air intake pipe assembly, and the bottom end of the outer insulation tube is connected to an exhaust pipe assembly.

[0007] As a further configuration of the above solution, each of the heat exchange gas inlets is provided with a gas inlet inclination adjustment plate.

[0008] As a further arrangement of the above scheme, the heat exchange gas inlet is fan-shaped, the gas inlet inclination adjustment plate matches the heat exchange gas inlet, and a shaft connected to the gas inlet inclination adjustment plate and rotatably extending out of the outer insulation tube is provided in the middle of the heat exchange gas inlet, a bevel gear is provided at the outer end of the shaft, a rotating ring is rotatably provided on the outer cylindrical surface of the outer insulation tube, and a bevel tooth surface that meshes with all the bevel gears at the same time is provided on the rotating ring.

[0009] As a further arrangement of the above scheme, a ring track interacting with the rotating ring is provided on the outer wall of the outer insulation cylinder, a large gear ring is provided on the rotating ring, an adjusting motor is installed on the outer insulation cylinder, and a power gear meshing with the large gear ring is provided on the motor shaft of the adjusting motor.

[0010] As a further configuration of the above solution, a fin ring is provided on the diversion heat exchange tube located below the partition ring.

[0011] As a further arrangement of the above scheme, the diverter includes an outer shell concentrically arranged above the inner settling cylinder, and connecting channels connected to the diversion heat exchange tubes are evenly opened on the circumferential surface of the outer shell. The inner ends of the multiple connecting channels extend toward the center of the outer shell and are arranged upwardly inclined, and the bottom wall at the center of the outer shell is provided with an upwardly protruding guide cone block.

[0012] As a further configuration of the above solution, the top of the diverter is connected to the dust air inlet pipe by a transition pipe, and the transition pipe includes a pipe body, and a converging channel is opened in the pipe body, which is wide at the top and bottom and narrow in the middle.

[0013] As a further arrangement of the above scheme, the air intake pipe assembly includes an air intake ring pipe, one end of the air intake ring pipe is connected to the air intake pipe, and the lower end of the air intake ring pipe is evenly provided with multiple air intake branches connected to the top end of the inner cavity of the outer insulation tube; the exhaust pipe assembly includes an air outlet ring pipe, one end of the air outlet ring pipe is connected to the air outlet pipe, and the upper end of the air outlet ring pipe is evenly provided with multiple air outlet branches connected to the bottom end of the inner cavity of the outer insulation tube.

[0014] During the operation of the dust airflow heat recovery equipment for zinc oxide preparation disclosed in the present invention, the oxidized zinc oxide powder airflow is fed into the diverter by the dust airflow inlet pipe, and through the internal structure of the diverter and the function of the transition pipe, the fed zinc oxide powder airflow can be first gathered to the center by the aggregation channel, and then evenly diffused to the surroundings, and with the function of the guide cone block, it can evenly enter each diversion heat exchange tube respectively. The contact area during heat exchange can be greatly improved through multiple diversion heat exchange tubes. Subsequently, the powder airflow is discharged from the bent nozzle at the lower end of the diversion heat exchange tube and sprayed upwardly towards the upper end of the central axis of the inner settling tube. The flow velocity of the powder airflow entering the inner settling tube will decrease sharply, thereby allowing large-sized zinc oxide particles to settle downward into the collecting hopper, and finally be discharged regularly through the discharge valve, effectively removing large-sized zinc oxide particles and ensuring the consistency of the size of the zinc oxide powder finally delivered.

[0015] At the same time, the external heat exchange air enters evenly from all sides of the outer insulation tube through the air inlet ring, and then enters the annular gap between the outer insulation tube and the inner sedimentation tube through the heat exchange gas inlet port on the partition ring. In the process of flowing through the annular gap, it can fully contact with the evenly arranged shunt heat exchange tubes and fin rings, thereby absorbing the heat in the zinc oxide dust airflow to achieve self-heating, and finally discharged from the air outlet ring for use. In addition, the present invention further provides a gas inlet inclination adjustment plate in the heat exchange gas inlet port. By adjusting the horizontal angle between the gas inlet inclination adjustment plate and the partition ring, the inclination angle of the heat exchange airflow entering between the outer insulation tube and the inner sedimentation tube through the heat exchange gas inlet port can be controlled, so that a spiral movement path is formed inside, which increases the contact time of the heat exchange gas with the shunt heat exchange tubes and fin rings, so that the heat of the zinc oxide powder airflow can be fully taken away.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The dust airflow heat recovery equipment for zinc oxide preparation disclosed in the present invention utilizes the function of a diverter to evenly distribute the zinc oxide powder airflow into a plurality of diverter heat exchange tubes, thereby effectively increasing the heat exchange area of ​​the powder airflow during heat exchange. In addition, the design of the gas inlet inclination adjustment plate allows the air entering the heat exchange annular gap to flow downward in a spiral shape, thereby increasing the contact time between the air and the diverter heat exchange tube. The combined effect of the above two can effectively improve the heat recovery and utilization effect of the heat of the zinc oxide powder airflow, and effectively reduce the temperature of the powder airflow finally sent to the bag collector, thereby avoiding the bag collector from interacting with the high-temperature powder airflow for a long time, thereby affecting its service life.

[0017] The dust airflow heat recovery equipment for zinc oxide preparation disclosed in the present invention can simultaneously discharge the zinc oxide powder airflow into an inner settling cylinder after diverting and conveying the zinc oxide powder airflow, thereby instantly reducing the pressure of the powder airflow and rapidly reducing the airflow velocity, thereby allowing large-size zinc oxide particles to settle downward into the collecting hopper, achieving effective separation from the zinc oxide powder, and improving the quality of the zinc oxide product finally collected. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 This is a schematic diagram of the external front three-dimensional structure of the present invention; Figure 2This is a schematic diagram of the back three-dimensional structure of the exterior of the present invention; Figure 3 This is a schematic diagram of the first-angle three-dimensional structure of the interior of the present invention; Figure 4 A schematic diagram of the interior three-dimensional structure of the present invention from a second angle; Figure 5 This is a schematic diagram of the three-dimensional structure of the inner settling cylinder, gas inlet angle adjustment plate, etc. in the present invention; Figure 6 Schematic diagram of the three-dimensional structure inside the diverter and transition pipe in the present invention; Figure 7 For the present invention Figure 4 A in the figure is an enlarged structural diagram. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of this application.

[0021] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of this application can be combined with each other. Figures 1 to 7 , and describes the application in detail with reference to embodiments. Example 1

[0022] Example 1 discloses a heat recovery device for dust airflow used in zinc oxide preparation, see the attached Figure 1-4 The main body of the equipment includes an outer insulation cylinder 1 and an inner sedimentation cylinder 2 arranged concentrically. The lower end of the inner sedimentation cylinder 2 is connected with a collecting hopper 3. The lower end of the collecting hopper 3 is connected with a sedimentation material discharge pipe 4 extending vertically from the outer insulation cylinder 1, and a discharge valve 5 is provided at the bottom of the sedimentation material discharge pipe 4. When the discharge valve 5 is in a closed state, it prevents the interior of the inner sedimentation cylinder 2 from being connected to the outside world.

[0023] A diverter 6 is provided in the inner cavity of the outer insulation tube 1 directly above the inner settling tube 2. The upper end of the diverter 6 is connected to a dust air inlet pipe 8 via a transition pipe 7. The end of the dust air inlet pipe 8 is connected to the conveying pipeline for dry-process zinc oxide preparation. A vertically downward dust air discharge pipe 9 is concentrically provided in the inner settling tube 2. A plurality of suction ports 901 are evenly arranged on the top circumferential surface of the dust air discharge pipe 9. The lower end of the dust air discharge pipe 9 is connected to a negative pressure suction pipe 10 extending from the side end of the sedimentation material discharge pipe 4. A negative pressure fan 11 is then connected to the end of the negative pressure suction pipe 10. The negative pressure fan 11 provides power to extract the dust airflow.

[0024] Reference Attachment Figure 3 , Attachment Figure 4 and attached Figure 6 The diverter 6 includes an outer shell 601 concentrically arranged above the inner settling cylinder 2. A plurality of connecting channels 602 are evenly arranged on the circumferential surface of the outer shell 601. The inner ends of the plurality of connecting channels 602 are all inclined upward toward the center of the outer shell 601, and then converge and connect at the center of the outer shell 601. The bottom wall at the center is provided with an upwardly protruding guide cone 603. The transition pipe 7 includes a pipe body 701 connected to the top of the outer shell 601, and a converging channel 702 with an hourglass shape that is wide at the top and bottom and narrow in the middle is provided in the pipe body 701. This allows the zinc oxide powder airflow fed along the dust air inlet pipe 8 to be first gathered toward the center by the converging channel 702, and then evenly diffused to the surroundings. With the help of the guide cone 603, it can evenly enter each connecting channel 602.

[0025] A vertically downward-facing shunt heat exchange tube 12 is connected to the outer end of each connecting channel 602 and is located between the inner wall of the outer insulation tube 1 and the outer wall of the inner settling tube 2. Fin rings 13 are also provided on the shunt heat exchange tubes 12 to increase the heat exchange area. A curved nozzle 14 is connected to the lower end of each shunt heat exchange tube 12 and is arranged to extend through the side wall of the collecting hopper 3 and open upward.

[0026] A partition ring 15 is connected between the top of the outer wall of the inner settling tube 2 and the outer insulation tube 1. A circular hole 151 is provided on the partition ring 15 for passing the diversion heat exchange tube 12, and a heat exchange gas inlet 152 is provided between two adjacent circular holes 151. Finally, an air intake ring 16 is provided at the top of the outer insulation tube 1. One end of the air intake ring 16 is connected to an air intake pipe 161. The lower end of the air intake ring 16 is evenly provided with a plurality of air intake branches connected to the top of the inner cavity of the outer insulation tube 1. An air outlet ring 17 is provided below the outer insulation tube 1. One end of the air outlet ring 17 is connected to an air outlet pipe 171. Similarly, the upper end of the air outlet ring 17 is evenly provided with a plurality of air outlet branches connected to the bottom of the inner cavity of the outer insulation tube.

[0027] During operation of the dust airflow heat recovery device for zinc oxide preparation disclosed in Example 1, the zinc oxide powder airflow obtained by dry process preparation is first introduced into the diverter 6 through the dust airflow inlet pipe 8. Then, the transition pipe 7 and the diverter 6 can evenly cooperate to enter the diverter heat exchange pipe 12, thereby greatly increasing the heat exchange area of ​​the zinc oxide powder airflow. The zinc oxide powder airflow entering the bottom of the diverter heat exchange pipe 12 is introduced into the inner settling tube 2 through the curved nozzle 14. Since the airflow velocity of the zinc oxide powder airflow decreases instantly after entering the inner settling tube 2, some larger zinc oxide particles will settle during the upward flow process, while the fine zinc oxide powder will be drawn into the dust airflow exhaust pipe 9 along with the airflow, and finally transported to the bag collector for processing through the negative pressure suction pipe 10 and the negative pressure fan 11.

[0028] At the same time, the external heat exchange air enters evenly from all sides of the outer insulation tube 1 through the air inlet ring 16, and then enters the annular gap between the outer insulation tube 1 and the inner sedimentation tube 2 through the heat exchange gas inlet port 152 on the partition ring 15. In the process of flowing through the annular gap, it can fully contact with the evenly arranged diversion heat exchange tube 12 and fin ring 13, thereby absorbing the heat in the zinc oxide dust airflow to achieve self-heating, and finally discharged from the air outlet ring 17 for utilization. Example 2

[0029] Example 2 discloses a dust airflow heat recovery device for zinc oxide preparation that is improved based on the technical solution in Example 1. The similarities with Example 1 are not described again.

[0030] Reference Attachment Figure 4 , Attachment Figure 5 and attached Figure 7 In this embodiment 2, the heat exchange gas inlet 152 on the partition ring 15 is designed in a fan shape, and a shaft 18 is provided at the center of the heat exchange gas inlet 152, which passes through the outer insulation tube 1 and is rotatable. A gas inlet inclination adjustment plate 19 adapted to the heat exchange gas inlet 152 is fixedly provided on the shaft 18, and a bevel gear 20 is provided at the outer end of the shaft 18 extending out of the insulation tube 1.

[0031] The outer surface of the insulation cylinder 1 is provided with an annular track 21, on which a rotating ring 22 is rotatably mounted. The upper end of the rotating ring 22 is provided with a bevel tooth surface that meshes with all bevel gears 20 simultaneously, and a large ring gear 23 is provided at the lower end of the rotating ring 22. An adjustment motor 24 is fixedly mounted on the outer wall of the insulation cylinder 1 via a protruding plate 26. This adjustment motor 24 is preferably a servo motor, and its pulse signal can be controlled to precisely control the rotation angle. A power gear 25 is provided on the motor shaft of the adjustment motor 24, which meshes with the large ring gear 23.

[0032] This embodiment 2 adopts the above-mentioned structural design, adjusts the power input of the motor 24, and then rotates the rotating ring 22 under the meshing transmission of the power gear 25 and the large gear ring 23. During the rotation of the rotating ring 22, the meshing transmission between the bevel tooth surface at its upper end and the bevel gear 20 allows all the gas inlet inclination adjustment plates 19 to rotate, thereby changing the horizontal angle between the gas inlet inclination adjustment plate 19 and the partition ring 15, so that the inclination angle of the heat exchange airflow entering between the outer insulation tube 1 and the inner sedimentation tube 2 through the heat exchange gas inlet port 152 is formed inside, so that a spiral movement path is formed, thereby increasing the contact time of the heat exchange gas with the diversion heat exchange tube 12 and the fin ring 13, so that it can fully take away the heat of the zinc oxide powder airflow.

[0033] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A dust airflow heat recovery device for zinc oxide preparation, characterized in that: The hopper is connected to the bottom end of the inner settling tube, and the lower end of the hopper is connected to the settling material discharge pipe with a discharge valve. The upper end of the inner cavity of the outer heat-insulating tube is provided with a diverter, and the top end of the diverter is connected to the dust air inlet pipe extending from the outer heat-insulating tube. The outer circumference of the diverter is evenly connected with a plurality of diversion heat exchange pipes extending vertically downward and passing through the annular gap between the outer heat-insulating tube and the inner settling tube, the lower end of the diversion heat exchange pipe is connected with a bent nozzle that passes through the collecting hopper and opens obliquely upward, and a dust air discharge pipe extending into the settling material discharge pipe is concentrically arranged in the inner settling tube, and a plurality of suction ports are evenly provided on the upper end of the dust air discharge pipe, and a negative pressure suction pipe extending from the side of the settling material discharge pipe is connected to the end of the negative pressure suction pipe. A partition ring is provided between the top of the outer circular surface of the inner settling tube and the inner wall of the outer insulation tube. A circular hole is provided on the partition ring for passing the diversion heat exchange tube. A heat exchange gas inlet is provided on the partition ring located between two adjacent circular holes. The top end of the outer insulation tube is connected to an air intake pipe assembly, and the bottom end of the outer insulation tube is connected to an exhaust pipe assembly.

2. The dust airflow heat recovery equipment for zinc oxide production according to claim 1, characterized in that: Each of the heat exchange gas inlets is provided with a gas inlet inclination adjustment plate.

3. The dust airflow heat recovery equipment for zinc oxide production according to claim 2, characterized in that: The heat exchange gas inlet is arranged in a fan shape, the gas inlet inclination adjustment plate matches the heat exchange gas inlet, and a shaft connected to the gas inlet inclination adjustment plate and rotatably extending out of the outer insulation cylinder is provided in the middle of the heat exchange gas inlet, a bevel gear is provided at the outer end of the shaft, a rotating ring is rotatably provided on the outer circular surface of the outer insulation cylinder, and a bevel tooth surface that meshes with all the bevel gears at the same time is provided on the rotating ring.

4. The dust airflow heat recovery equipment for zinc oxide production according to claim 3, characterized in that: The outer wall of the outer heat-insulating cylinder is provided with an annular track that interacts with the rotating ring, the rotating ring is provided with a large gear ring, the outer heat-insulating cylinder is installed with an adjusting motor, and the motor shaft of the adjusting motor is provided with a power gear that meshes with the large gear ring.

5. The dust airflow heat recovery equipment for zinc oxide production according to claim 1, characterized in that: A fin ring is provided on the diversion heat exchange tube located below the partition ring.

6. The dust airflow heat recovery equipment for zinc oxide production according to claim 1, characterized in that: The diverter includes an outer shell concentrically arranged above the inner settling cylinder, and connecting channels connected to the diversion heat exchange pipes are evenly opened on the circumferential surface of the outer shell. The inner ends of multiple connecting channels extend toward the center of the outer shell and are arranged upwardly inclined, and the bottom wall at the center of the outer shell is provided with an upwardly protruding guide cone block.

7. The dust airflow heat recovery equipment for zinc oxide production according to claim 6, characterized in that: The top end of the diverter is connected to the dust air inlet pipe by a transition pipe. The transition pipe comprises a pipe body. A convergence channel is opened in the pipe body, which is wide at the top and bottom and narrow in the middle.

8. The dust airflow heat recovery equipment for zinc oxide production according to claim 1, characterized in that: The air intake pipe assembly includes an air intake ring pipe, one end of the air intake ring pipe is connected to the air intake pipe, and the lower end of the air intake ring pipe is evenly provided with multiple air intake branches connected to the top end of the inner cavity of the outer insulation tube. The exhaust pipe assembly includes an air outlet ring pipe, one end of the air outlet ring pipe is connected to the air outlet pipe, and the upper end of the air outlet ring pipe is evenly provided with multiple air outlet branches connected to the bottom end of the inner cavity of the outer insulation tube.

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