Disc dryer applied to coking wastewater treatment

Abstract

The present application belongs to the technical field of sludge drying, and particularly relates to a disc dryer applied to coking wastewater treatment, which aims to solve the problems of easy fouling and wear of the disc surface and loss of heat energy caused by secondary condensation of water vapor, and comprises a shell, staggered upper and lower drying discs arranged in the shell, a step-by-step material pushing mechanism arranged above the drying discs, a cavity arranged in the drying disc, a vertical pipe and a gas guide pipe for introducing steam to heat the disc surface, a gas guide mechanism comprising a conical pipe fixed below the drying disc and turbine blades on the hollow shaft for guiding the water vapor generated during drying into the hollow shaft through the gas inlet hole and discharging it outward, and movable rake nails arranged on the pushing plate for plowing hard materials downward when they are encountered. The device can reduce fouling and wear of the disc surface and reduce the secondary condensation of steam in the equipment.

Description

Technical Field

[0001] This invention relates to the field of sludge drying technology, and more particularly to a disc dryer for coking wastewater treatment. Background Technology

[0002] In the process of coking wastewater treatment, a large amount of sludge is generated. This sludge has a high water content and needs to be dried for subsequent transportation, disposal, or resource utilization. A disc dryer is a commonly used device for sludge drying. It uses multiple fixed or rotating drying discs and a heat medium for indirect heating to evaporate the water in the sludge.

[0003] refer to Figure 14-15 Current disc dryers have some problems when treating coking wastewater sludge: Coking wastewater sludge is highly viscous and easily forms scale on the drying trays, affecting heat transfer efficiency. If the large amount of steam generated during the drying process cannot be discharged in time, it will condense inside the dryer and drip back onto the sludge surface, causing the dried sludge to become damp again and reducing drying efficiency. In addition, existing feeding mechanisms lack effective means to handle hard foreign objects that may be mixed in with the sludge, which can easily cause equipment jamming or wear.

[0004] Therefore, there is a need for a disc dryer that can effectively treat coking wastewater sludge and solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to solve the problems of existing disc dryers in treating coking sludge, such as easy scaling and wear on the disc surface, secondary condensation of water vapor generated during drying leading to heat loss, and difficulty in handling hard foreign objects. Therefore, this invention proposes a disc dryer for coking wastewater treatment.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A disc dryer for treating coking wastewater includes: The casing has a top cover; A hollow shaft is rotatably disposed between the bottom inner wall of the housing and the top inner wall of the top cover; Multiple upper and lower drying discs are arranged longitudinally and alternately inside the housing. The upper drying discs are located above the lower drying discs and are provided with discharge holes. A heating mechanism, located inside the housing, is used to dry the sludge slurry; A tiered feeding mechanism, located above each of the upper and lower drying trays and rotating with the hollow shaft, is used to convey the sludge slurry downwards tier by tier; and A gas guiding mechanism is used to discharge steam from the housing during the drying process; The step-by-step feeding mechanism located above the upper drying tray pushes the sludge slurry from the outside to the inside and discharges it through the discharge hole to the adjacent lower drying tray below. The step-by-step feeding mechanism located above the lower drying tray pushes the sludge slurry from the inside to the outside and discharges it through the edge of the lower drying tray to the adjacent upper drying tray below.

[0007] In one possible design, the heating mechanism includes two vertical pipes fixed to both sides of the housing, as well as two air guide pipes I and multiple air guide pipes II. The two air guide pipes I are respectively fixedly connected to the two vertical pipes. Both the upper drying tray and the lower drying tray are provided with cavities. One end of the air guide pipe II is fixedly connected to the vertical pipe, and the other end extends into the corresponding cavity, for heating the upper drying tray and the lower drying tray to dry the sludge slurry.

[0008] In one possible design, the step-by-step feeding mechanism includes a fixed ring fixed to the outer wall of the hollow shaft, a support arm fixed to the fixed ring, and a dial plate rotatably connected to the support arm via a fixed shaft. A torsion spring is sleeved on the fixed shaft, and the two ends of the torsion spring are respectively connected to the support arm and the dial plate. A limiting plate is fixed to the bottom of the support arm to limit the reset rotation position of the dial plate.

[0009] In one possible design, the step-by-step feeding mechanism further includes an arc-shaped plate fixed to the side of the feeding plate near the fixed ring. The arc-shaped plate is provided with multiple hemispherical blocks for crushing the dry and hardened slurry. When the feeding plate rotates to scrape the material, the arc-shaped plate crushes the dry and hardened scale and causes the feeding plate to rotate to avoid hard foreign objects.

[0010] In one possible design, a plowing mechanism is also included, which includes a lifting plate slidably connected to one side of the lever plate, a fixed seat fixed to the lever plate, a sliding rod slidably passing through the fixed seat and fixed at its top end to the lifting plate, and a spring sleeved on the sliding rod and located between the fixed seat and the lifting plate. The bottom of the lifting plate is connected to a rake nail through a sliding seat, and the bottom end of the rake nail slidably passes through the arc-shaped plate.

[0011] In one possible design, the plowing mechanism further includes a fixed box fixed to the top of the lifting plate and a groove provided on the lever plate. The bottom inner wall of the fixed box has a first inclined surface, and the bottom inner wall of the groove has a second inclined surface. A lead ball is placed in the groove. When the lever plate rotates and tilts, the lead ball rolls into the fixed box and drives the lifting plate to move downward, causing the rake nail to extend out of the arc-shaped plate to plow hard foreign objects. When the lever plate returns to its original position, the lead ball rolls back into the groove under the action of the first inclined surface, and the lifting plate returns to its original position under the action of the spring.

[0012] In one possible design, the air guiding mechanism includes a tapered tube fixed to the bottom of the upper and lower drying trays. The tapered tube is sleeved on the outer wall of the hollow shaft, with its top inner diameter smaller than its bottom inner diameter. An air inlet is provided inside the tapered tube within the hollow shaft. Turbine blades located inside the tapered tube are fixed to the outer wall of the hollow shaft. An exhaust pipe connected to an external negative pressure device is fixed on the top cover, with its bottom end extending into the hollow shaft. The hollow shaft drives the turbine blades to rotate, creating a negative pressure inside the tapered tube, drawing moisture into the hollow shaft through the air inlet and discharging it through the exhaust pipe.

[0013] In one possible design, the bottom of the housing is fixed with multiple rigid legs, and a mounting plate is fixed between the multiple rigid legs. A drive motor is fixed on the mounting plate, and a gearbox is fixed to the bottom of the housing. The output shaft of the drive motor is fixedly connected to the input shaft of the gearbox, and the output end of the gearbox is fixedly connected to the bottom end of the hollow shaft for driving the hollow shaft to rotate.

[0014] In one possible design, the housing contains a plurality of fixing plates I for supporting the upper drying tray and a plurality of fixing plates II for supporting the lower drying tray. Fixing plates I are fixedly connected to the upper drying tray by bolts, and fixing plates II are fixedly connected to the lower drying tray by bolts. The outer wall of the upper drying tray is fixed with a skirt to prevent mud from falling off its edge.

[0015] In one possible design, a discharge pipe is fixed to the bottom of the housing, and multiple arc-shaped material-pushing plates that slide against the inner wall of the bottom of the housing are fixed to the outer wall of the hollow shaft. The arc center of the arc-shaped material-pushing plates corresponds to the position of the discharge pipe and is used to gather and discharge the dried slurry to the discharge pipe.

[0016] Beneficial effects: In this invention, by setting up staggered upper and lower drying trays, and setting up progressive feeding mechanisms with opposite feeding directions on the upper and lower drying trays, the sludge slurry forms an "S"-shaped movement path from top to bottom, first converging inward and then dispersing outward during the drying process. This prolongs the residence time of the material in the drying area, increases the number of times the material contacts the heating plate surface and the frequency of turning, making the material more evenly heated and the drying effect better. In this invention, the step-by-step feeding mechanism is equipped with an elastic swing-type feeding plate with a torsion spring and a limiting plate, and an arc plate with a hemispherical block on one side. This allows the feeding plate to generate extrusion pressure through the arc plate to perform preliminary crushing when it encounters dry and hard sludge, and to elastically avoid hard foreign objects that are difficult to crush. This effectively reduces the risk of wear or damage to the equipment due to jamming or direct impact, and improves the operational stability and service life of the equipment. In this invention, the plowing mechanism utilizes the tilted state of the deflector when avoiding foreign objects to trigger the rolling of the lead ball and drive the rake nail to extend, thereby actively crushing hard foreign objects. It utilizes the movement and gravity changes of the equipment itself, without the need for additional power sources and control components. The structure is compact, the operation is reliable, and the equipment's adaptability to complex material compositions is enhanced. In this invention, by combining the turbine blades on the hollow shaft with the conical tube, a local Venturi negative pressure effect is formed near the drying area. With the help of external negative pressure equipment, the water vapor generated during drying can be quickly and actively drawn away from the vicinity of the source and discharged, avoiding the rise, diffusion and condensation of steam inside the equipment, preventing the dried material from becoming damp again, improving drying efficiency, and also helping to maintain the stability of the internal environment of the equipment. In this invention, by using the hollow shaft as a drive shaft and air channel, and integrating the heating pipeline, feeding mechanism, and air guiding mechanism into the housing, the overall structure is compact and highly integrated, which helps to reduce the equipment's footprint and simplifies the connection of external pipelines.

[0017] In this invention, the staggered arrangement of drying trays and the opposing material feeding mechanism create a specific long-path movement of the sludge slurry within the machine, increasing the contact and tumbling of the material with the hot tray surface and ensuring uniform drying. The material feeding mechanism has dual functions of elastic avoidance and active crushing. On the one hand, the design of the torsion spring and arc plate allows the feeding plate to avoid hard objects, reducing the risk of equipment wear. On the other hand, the gravity triggering of the lifting plate by the lead ball drives the rake nail to extend, effectively crushing hard foreign objects and improving the equipment's adaptability to complex material conditions. In addition, the turbine blades and conical tube cooperate to form a negative pressure inside the hollow shaft, and with the help of external suction, the steam generated during drying is quickly discharged, effectively preventing the steam from condensing and becoming damp inside the equipment, thus ensuring drying efficiency. Attached Figure Description

[0018] Figure 1 This is a three-dimensional structural schematic diagram of a disc dryer for coking wastewater treatment provided by the present invention; Figure 2 This is a three-dimensional exploded structural diagram of a disc dryer for coking wastewater treatment provided by the present invention; Figure 3 This is a three-dimensional exploded cross-sectional view of the shell and upper drying disc of a disc dryer for coking wastewater treatment provided by the present invention. Figure 4 This is a three-dimensional structural diagram of the upper and lower drying trays of a disc dryer for coking wastewater treatment provided by the present invention. Figure 5This is a three-dimensional exploded view of the upper and lower drying discs of a disc dryer for coking wastewater treatment provided by the present invention. Figure 6 This is a three-dimensional cross-sectional view of the upper and lower drying discs of a disc dryer for coking wastewater treatment provided by the present invention. Figure 7 A three-dimensional structural diagram of the support arm and the lever plate of a disc dryer for coking wastewater treatment provided by the present invention; Figure 8 This is a three-dimensional exploded structural diagram of the paddle plate, U-shaped rod, and arc plate of a disc dryer for coking wastewater treatment provided by the present invention; Figure 9 This is a three-dimensional exploded structural diagram of the rake, fixed base, and lifting plate of a disc dryer for coking wastewater treatment provided by the present invention. Figure 10 This is a three-dimensional exploded structural diagram of the slide bar and fixed base of a disc dryer used for coking wastewater treatment provided by the present invention; Figure 11 This is a partial three-dimensional cross-sectional structural diagram of the fixed box and the sliding plate of a disc dryer for coking wastewater treatment provided by the present invention; Figure 12 This is a three-dimensional structural diagram of the hollow shaft and tapered tube of a disc dryer for coking wastewater treatment provided by the present invention. Figure 13 This is a three-dimensional cross-sectional structural diagram of the conical tube and hollow shaft portion of a disc dryer for coking wastewater treatment provided by the present invention; Figure 14 A schematic diagram of the internal structure of an existing disc dryer; Figure 15 This is a schematic diagram of an existing disc dryer.

[0019] In the diagram: 1. Shell; 2. Rigid support leg; 3. Mounting plate; 4. Drive motor; 5. Gearbox; 6. Top cover; 7. Hollow shaft; 8. Feed hopper; 9. Vertical pipe; 10. Air guide pipe I; 11. Fixing plate I; 12. Upper drying tray; 13. Skirt; 14. Discharge hole; 15. Fixing plate II; 16. Lower drying tray; 17. Cavity; 18. Air guide pipe II; 19. Fixing ring; 20. Support arm; 21. U-shaped rod; 22. Paddle plate; 23. Fixing shaft; 24. Fixing plate; 25. Torsion spring; 26. Limiting plate; 27. Arc plate; 28. Hemispherical block; 29. ​​Lifting plate; 30. Fixed seat; 31. Slide rod; 32. Spring; 33. Limiting ring; 34. Slide seat; 35. Rake nail; 36. Fixed box; 37. First inclined surface; 38. Groove; 39. Second inclined surface; 40. Lead ball; 41. Inclined rod; 42. Conical tube; 43. Air inlet; 44. Discharge pipe; 45. Turbine blade; 46. Exhaust pipe; 47. Observation window; 48. Arc-shaped feeding plate. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0021] In one embodiment: Refer to Figures 1-3 A disc dryer for coking wastewater treatment, relating to the field of sludge drying technology, mainly includes a shell 1 serving as the outer casing. A top cover 6 is fixedly connected to the top of the shell 1 by multiple bolts. The top cover 6 is used to close the upper opening of the shell 1. A feed hopper 8 for feeding sludge slurry to be treated is fixedly installed at a position off-center from the top cover 6. Between the center of the bottom inner wall of the shell 1 and the center of the top inner wall of the top cover 6, a hollow shaft 7 is rotatably supported by a bearing in a vertical direction. The hollow shaft 7 is a hollow structure and is the core transmission and air guiding component of this equipment.

[0022] Reference Figures 3-5 Inside the housing 1, multiple upper drying discs 12 and multiple lower drying discs 16 are arranged along its longitudinal direction (i.e., vertical direction). These upper drying discs 12 and lower drying discs 16 are hollow disc-shaped structures with space inside to accommodate the heat medium. The multiple upper drying discs 12 and multiple lower drying discs 16 are staggered in the vertical direction, that is, a lower drying disc 16 is arranged directly below each upper drying disc 12, and the upper drying disc 12 is located above the lower drying disc 16. Multiple discharge holes 14 for material to fall are opened on the disc surface of each upper drying disc 12. These discharge holes 14 are usually located near the center of the upper drying disc 12. The top end of the hollow shaft 7 rotates through the lower drying disc 16, and the top end of the hollow shaft 7 passes through the discharge holes 14.

[0023] Reference Figure 2 , Figure 3 and Figure 6 The housing 1 contains a heating mechanism for drying the injected sludge slurry. This mechanism includes two vertical pipes 9 fixed to the outer walls of both sides of the housing 1, extending vertically. It also includes two air guide pipes I 10, which are fixed to and connected to the bottom of the two vertical pipes 9, respectively, for supplying a heat medium, such as high-temperature steam or heat transfer oil, into the vertical pipes 9. Both the upper drying tray 12 and the lower drying tray 16 have cavities 17 for containing the heat medium. Multiple air guide pipes II 18 are fixedly connected to the side of the two vertical pipes 9 closest to each other, i.e., the side facing the interior of the housing 1. One end of each air guide pipe II 18 passes through the side wall of the housing 1 and is further... The steam is extended into the cavity 17 of the corresponding upper drying tray 12 or lower drying tray 16 and fixedly connected to it. In this way, high-temperature steam is injected into the vertical pipe 9 connected to it through the air guide pipe I 10 located on the left side of the housing 1. The steam will enter the cavity 17 of each upper drying tray 12 and lower drying tray 16 through multiple air guide pipes II 18 on the vertical pipe 9, thereby raising the temperature of the upper drying tray 12 and lower drying tray 16, thereby heating and drying the sludge slurry falling on its top surface. After releasing heat, the steam in the cavity 17 flows into the vertical pipe 9 on the right side of the housing 1 through the air guide pipe II 18 on the other side, and finally exits through the air guide pipe I 10 at the bottom of the vertical pipe 9, realizing the recovery and reuse of steam.

[0024] Reference Figure 4 and Figure 5 A step-by-step feeding mechanism is provided above both the upper drying tray 12 and the lower drying tray 16. The step-by-step feeding mechanism above the upper drying tray 12 is used to push the sludge slurry falling on the top surface of the upper drying tray 12 from the outer edge of the drying tray towards the center, and to discharge the sludge slurry through the discharge hole 14 to the top of the adjacent lower drying tray 16. The step-by-step feeding mechanism above the lower drying tray 16 is used to push the sludge slurry falling on the top surface of the lower drying tray 16 from the center of the drying tray towards the outer edge, and to discharge the sludge slurry through the edge of the lower drying tray 16 to the top of the adjacent upper drying tray 12. Through this staggered arrangement of drying trays and the opposite feeding action, the sludge slurry forms an "S"-shaped movement path inside the dryer, moving from top to bottom, first converging inward and then dispersing outward, thereby extending the residence time of the material in the drying area and increasing the contact opportunity with the hot tray surface.

[0025] Reference Figure 7 and Figure 8The step-by-step feeding mechanism includes a fixing ring 19 fixed to the outer wall of the hollow shaft 7. The fixing ring 19 is located directly above the corresponding upper drying tray 12. Multiple outwardly radiating support arms 20 are fixedly welded to the outer wall of the fixing ring 19 along its circumference. Multiple U-shaped rods 21 are fixedly inserted through each support arm 20. A deflector plate 22 is located below each U-shaped rod 21. The deflector plate 22 is used to directly contact and push the sludge slurry. A fixed shaft 23 is fixed to the top of the deflector plate 22 via a base. The bottom of the U-shaped rod 21 is rotatably sleeved on the outer wall of the fixed shaft 23, allowing the deflector plate 22 to swing at a certain angle relative to the U-shaped rod 21. A fixed sleeve is fixed to the outer wall of the fixed shaft 23. A fixed plate 24 is provided, and a torsion spring 25 is fixedly connected to both sides of the fixed plate 24 through spring seats. The ends of the two torsion springs 25 that are far apart from each other are also fixedly connected to the U-shaped rod 21 through spring seats. The entire torsion spring 25 is also sleeved on the outer wall of the fixed shaft 23. The parameter range of the torsion spring 25 can be selected according to the size of the dial plate 22 and the expected force. At the bottom of the support arm 20, near the fixed ring 19, a limiting plate 26 is fixedly provided. The limiting plate 26 is located between the dial plate 22 and the fixed ring 19. Its function is to limit the final position of the dial plate 22 when the torsion spring 25 drives the dial plate 22 to reset and rotate, so that the dial plate 22 maintains a predetermined tilt angle or vertical state in its natural state.

[0026] Specifically, when the drive motor 4 drives the hollow shaft 7 to rotate through the gearbox 5, the hollow shaft 7 will drive the fixed ring 19 and the support arm 20 to rotate together. The rotation of the support arm 20 will drive the multiple paddles 22 on it to move in a circle around the axis of the hollow shaft 7. For the upper drying tray 12, the rotating paddles 22 will scrape the sludge slurry falling on the upper drying tray 12 from the outer edge of the tray surface towards the center, and finally make the sludge slurry fall through the discharge hole 14 in the center of the tray surface to the next lower drying tray 16 for the next stage of drying.

[0027] Reference Figure 7 and Figure 8 In order to enhance the ability to handle the hardened sludge that may occur, the step-by-step feeding mechanism further includes an arc-shaped plate 27 fixed on the side of the feeding plate 22 near the fixed ring 19. The curvature of the arc-shaped plate 27 is towards the front of the movement of the feeding plate 22. On one side of the arc-shaped plate 27, that is, the side facing the direction of movement, a plurality of hemispherical blocks 28 are fixedly arranged.

[0028] Specifically, when the support arm 20 drives the deflector plate 22 to rotate and scrape the sludge slurry, if it encounters dried and hardened sludge or small pieces of scale, the arc plate 27 can generate a downward pressure at its front end, which helps to crush these hard pieces. When it encounters a large foreign object with high hardness, the deflector plate 22 will be subjected to a large reverse force. Since the deflector plate 22 is rotatably connected to the U-shaped rod 21 through the fixed shaft 23 and the torsion spring 25, this force will overcome the elasticity of the torsion spring 25, causing the deflector plate 22 to rotate backward around the fixed shaft 23 as the center to avoid the hard object. This prevents the surface of the upper drying disc 12 from being directly scraped and worn by the hard object. After passing the hard foreign object, the deflector plate 22 will return to its original position under the restoring force of the torsion spring 25 until it is blocked by the limit plate 26 and returns to its normal working angle.

[0029] Reference Figures 8-10 To further handle larger, hard foreign objects that the deflector plate 22 may encounter, this disc dryer is also equipped with a plowing mechanism. This plowing mechanism includes a lifting plate 29 slidably connected to the side of the deflector plate 22 near the arc-shaped plate 27. Multiple fixed seats 30 are fixed to the body of the deflector plate 22, located below the lifting plate 29. A sliding rod 31 slides through each fixed seat 30, with its top end extending upwards and fixedly connected to the bottom of the lifting plate 29. Between the fixed seat 30 and the lifting plate 29, a spring 32 sleeved on the outer wall of the sliding rod 31 applies an upward thrust to the lifting plate 29 through spring seats at both ends. A limiting ring 33 is fixedly sleeved on the outer wall of each sliding rod 31, located below the fixed seat 30, to limit... Ring 33 is used to limit the maximum upward sliding stroke of slide bar 31, that is, to limit the highest position of lifting plate 29 under the action of spring 32. Multiple slide blocks 34 are slidably connected to the bottom of lifting plate 29 through multiple slide rails, so that slide blocks 34 can be adjusted or floated in a small range in the horizontal direction at the bottom of lifting plate 29. Each slide block 34 has a downwardly extending rake nail 35 fixed at the bottom. The bottom ends of these rake nails 35 slide downward through the preset through holes on arc plate 27, so that in the initial state, the tip of the rake nail 35 is retracted above or flush with arc plate 27. When the lever plate 22 and arc plate 27 encounter large hard foreign objects during rotation, the mechanism can make the rake nail 35 extend downward, thereby plowing the hard foreign objects.

[0030] To prevent dust and sticky substances from the coking sludge from entering the moving parts of the plowing mechanism, a dustproof sealing ring (not shown in the figure) is provided at the penetration point between the slide rod 31 and the fixed seat 30; a retractable corrugated dustproof cover (not shown in the figure) is also provided at the sliding track between the slide seat 34 and the lifting plate 29. In addition, all surfaces of sliding parts exposed inside the housing 1 are treated with a hardened and anti-corrosion coating.

[0031] Reference Figures 8-11The plowing mechanism also includes multiple fixed boxes 36 fixed to the top of the lifting plate 29. The interior of the fixed box 36 is hollow, and its bottom inner wall is set as a first inclined surface 37 that gradually rises from the side near the lever plate 22 to the side away from the lever plate 22. Correspondingly, on one side of the lever plate 22, that is, at the position opposite to the fixed box 36, multiple grooves 38 are provided. The number and position of the grooves 38 correspond one-to-one with the fixed boxes 36. The bottom inner wall of the groove 38 is provided with a second inclined surface 39 that gradually decreases from the outside to the inside. The inclination direction of the second inclined surface 39 is the same as that of the first inclined surface 37. A freely rolling lead ball 40 is placed in each groove 38. In addition, on one side of the lever plate 22, below all the lifting plates 29, multiple limiting blocks are fixed. These limiting blocks are used to limit the maximum distance that the lifting plate 29 moves downward to prevent it from moving too far downward.

[0032] Specifically, when the arc plate 27 and the lever 22 encounter a hard foreign object during rotation, causing the lever 22 to rotate backward and tilt, the lead ball 40 in the groove 38 will roll along the second inclined surface 39 due to its own gravity, and cross the gap between the lever 22 and the fixed box 36, entering the fixed box 36. After the lead ball 40 enters the fixed box 36, its gravity will act on the fixed box 36, thereby pulling the entire lifting plate 29 downward against the elastic force of the spring 32. When the lifting plate 29 moves downward, it will drive the rake nail 35 downward through the slide 34, so that the tip of the rake nail 35 extends downward from the through hole of the arc plate 27. At this time, although the lever 22 is tilted to avoid the foreign object, the extended rake nail 35 can still move downward when the support arm 20 drives the lever 22 to continue rotating. The lever 22 can reach hard foreign objects and use its sharp end to crush or scratch them. When the lever 22 passes the hard foreign object and is no longer blocked, under the action of the torsion spring 25, the lever 22 will rotate in the opposite direction to return to the vertical state. During this process, the fixed box 36 and the lifting plate 29 also return to the near vertical direction. The lead ball 40 in the fixed box 36 will roll towards the lever 22 under the guidance of the first inclined surface 37, cross the gap again and enter the groove 38, and stay at the low position of the second inclined surface 39. As the lead ball 40 leaves the fixed box 36, the lifting plate 29 loses the downward pull and returns to the upward reset under the push of the spring 32 until the limit ring 33 contacts the fixed seat 30. At this time, the rake nail 35 is also pulled back to the inside or above the arc plate 27, waiting for the next trigger.

[0033] During the process of entering the fixed box 36, it should be noted that at normal rotational speed, the centrifugal force on the lead ball 40 within the groove 38 causes it to tend to move outwards. This ensures that the rake nail 35 will not accidentally extend during normal scraping. The plowing action is only triggered when the deflector 22 tilts backwards due to encountering a hard foreign object, causing a change in the inclination angle of the second inclined surface 39. This results in the inward component of the gravity acting on the lead ball 40 being sufficient to overcome the centrifugal force. By appropriately setting the inclination angle of the second inclined surface 39, the mass of the lead ball 40, and the maximum rotational speed of the equipment, the reliability and selectivity of this triggering mechanism under predetermined operating conditions can be ensured. Furthermore, a small ramp pointing towards the fixed box can be provided at the gap between the groove 38 and the fixed box 36 to assist in the introduction of the lead ball.

[0034] Reference Figure 3 , Figure 12 and Figure 13 The disc dryer also includes a gas guiding mechanism to quickly discharge the steam evaporated from the sludge during the drying process from inside the shell 1, preventing secondary condensation of the steam on the inner wall of the shell 1 or at the bottom of the upper drying disc, thus ensuring drying efficiency. This gas guiding mechanism includes multiple connecting groups fixed to the bottom of the upper drying disc 12, the bottom of the lower drying disc 16, and the inner wall of the top of the top cover 6. Each connecting group consists of multiple radially or evenly distributed diagonal rods 41. The bottom end of each connecting group is fixedly connected to a tapered tube 42, which has a flared shape (smaller at the top and larger at the bottom) and is coaxially sleeved on the outer wall of the hollow shaft 7. An annular gap is left between the outer walls of the hollow shaft 7. On the tube wall of the hollow shaft 7, in the area covered by each tapered tube 42, multiple air inlets 43 are opened through the tube wall. On the outer wall of the hollow shaft 7, inside each tapered tube 42, multiple turbine blades 45 are fixedly fitted. An exhaust pipe 46 is fixedly inserted through the top center of the top cover 6. The bottom end of the exhaust pipe 46 extends downward and passes through the top cover 6 and is rotatably connected to the top end of the hollow shaft 7 through a rotary joint, thereby communicating with the internal cavity of the hollow shaft 7. The top end of the exhaust pipe 46 extends out of the top cover 6 and is connected to the external negative pressure generating equipment, such as an induced draft fan, through a pipe.

[0035] Specifically, when the heating mechanism is working, the steam in the cavity 17 heats the sludge on the upper drying tray 12 and the lower drying tray 16. The water in the sludge evaporates due to the heat, forming hot, moist steam. This steam diffuses upwards and outwards. At the same time, the hollow shaft 7 rotates under the drive mechanism, and the turbine blades 45 fixed on its outer wall also rotate at high speed in the internal space of the conical tube 42. The rotation of the turbine blades 45 generates a centrifugal suction effect, which accelerates the airflow inside the conical tube 42 and forms a local negative pressure. Because the upper opening of the conical tube 42 is small and the lower opening is large, this structure, combined with the rotation of the turbine blades 45, creates a local negative pressure inside the conical tube 42. A Venturi effect is formed in the region, further enhancing the negative pressure. Under the attraction of the negative pressure, the hot and humid steam diffused around the drying tray, along with any small amount of dust it may carry, is quickly drawn into the annular space between the conical tube 42 and the hollow shaft 7, and enters the internal cavity of the hollow shaft 7 through the air inlet 43. Since the exhaust pipe 46 is connected to the negative pressure equipment, the inside of the hollow shaft 7 is also under negative pressure. The hot and humid steam entering the hollow shaft 7 is immediately drawn upward and discharged to the outside of the shell 1 through the exhaust pipe 46, where it undergoes subsequent dust removal and heat recovery treatment. In this way, the water vapor generated during the drying process is forced and quickly discharged, preventing it from condensing and accumulating inside the equipment.

[0036] Reference Figure 5 and Figure 7 In order to ensure that the material can be conveyed along a predetermined path, the orientation of the paddle plate 22 in the step-by-step feeding mechanism in the upper drying tray 12 is opposite to that in the step-by-step feeding mechanism in the lower drying tray 16. Specifically, the paddle plate 22 used in the upper drying tray 12 pushes the material in the direction of the hollow shaft 7, that is, from the outside to the inside; the paddle plate 22 used in the lower drying tray 16 pushes the material in the direction away from the hollow shaft 7, that is, from the inside to the outside.

[0037] Reference Figures 1-3 One or more observation windows 47 are fixedly installed on one side of the outer wall of the housing 1 for operators to observe the internal operation of the equipment and the drying status of the materials. Multiple rigid support legs 2 are fixedly welded to the bottom of the housing 1 to support the entire equipment. A mounting plate 3 is fixedly connected between these rigid support legs 2 for mounting the drive components. The drive motor 4 is fixedly installed on the top of the mounting plate 3. The gearbox 5 is fixedly installed at the bottom center of the housing 1. Its output shaft extends rotatably into the interior of the housing 1 through a seal and is fixedly connected to the bottom end of the hollow shaft 7 through a coupling. The output shaft of the drive motor 4 is fixedly connected to the input shaft of the gearbox 5. The power output by the drive motor 4 is adjusted by the gearbox 5 and drives the hollow shaft 7 to rotate at the required speed.

[0038] Reference Figure 3 and Figure 5To support and fix the drying trays, multiple annular fixing plates I11 are fixed on the inner wall of the housing 1. These fixing plates I11 are used to support and fix the outer edge of the upper drying tray 12 and are fixed to the upper drying tray 12 with bolts. Similarly, multiple annular fixing plates II15 are also fixed on the inner wall of the housing 1. These fixing plates II15 are used to support and fix the outer edge of the lower drying tray 16 and are fixed to the lower drying tray 16 with bolts. On the outer circumferential edge of each upper drying tray 12, a skirt 13 with an upward protrusion is fixedly provided. The function of the skirt 13 is to prevent the sludge slurry on the upper drying tray 12 from falling directly from the edge of the tray to the next layer under the action of centrifugal force or the material feeding plate, ensuring that the material can only fall through the central discharge hole 14, thereby ensuring that the material follows the predetermined "outside to inside" path.

[0039] In addition, this disc dryer also includes a control system. The control system includes a PLC controller (not shown in the figure), which is electrically connected to the drive motor 4, the steam inlet valve (not shown in the figure) that supplies heat to the vertical pipe 9, and the external negative pressure equipment (not shown in the figure). According to the preset program or the feedback signals from the temperature and humidity sensors (not shown in the figure) installed inside the shell 1, the PLC controller coordinates and controls the speed of the drive motor 4 to adjust the material residence time, controls the opening of the steam valve to adjust the drying temperature, and controls the start and stop of the negative pressure equipment to maintain a suitable negative pressure inside the shell 1, thereby realizing the automated control of the drying process.

[0040] In another embodiment: Refer to Figure 3 and Figure 12 At the lowest point of the bottom of the housing 1, a discharge pipe 44 for discharging the final dried product is fixedly installed. On the outer wall of the hollow shaft 7, near the bottom of the housing 1, a plurality of arc-shaped material-pushing plates 48 are fixedly connected. The bottom of these arc-shaped material-pushing plates 48 slides in contact with the bottom inner wall of the housing 1. Each arc-shaped material-pushing plate 48 is curved, and the center of its arc points to the location of the discharge pipe 44.

[0041] Specifically, when the hollow shaft 7 drives the arc-shaped material feeding plate 48 to rotate, the arc-shaped material feeding plate 48 will scrape the dried sludge accumulated at the bottom of the housing 1 and move it along the curved surface of the arc-shaped material feeding plate 48 to the position with the largest arc, that is, the central area of ​​the arc. Since the discharge pipe 44 is set at this convergence point, the dried sludge can be smoothly discharged out of the machine through the discharge pipe 44, completing the entire drying process.

[0042] A method of using a disc dryer for coking wastewater treatment includes the following steps: S1. During operation, the coking wastewater sludge slurry to be dried is continuously fed into the feed hopper 8, first falling onto the top surface of the upper drying tray 12 located at the top layer. The drive motor 4 starts, and its output power, after being adjusted by the gearbox 5, drives the hollow shaft 7 to rotate at a set speed. The rotation of the hollow shaft 7 drives all the components fixedly connected to it, including the fixing rings 19 above each drying tray, the support arms 20, the actuating plates 22, as well as the turbine blades 45 located on the outer wall of the hollow shaft 7 and the arc-shaped actuating plates 48 at the bottom, all rotating around the hollow shaft 7. As the axis rotates, the heating mechanism starts working. High-temperature steam is injected from the air guide pipe I10 on the left side of the shell 1, enters the vertical pipe 9 on the left side, and flows into the cavity 17 of each upper drying plate 12 and lower drying plate 16 through multiple air guide pipes II18 connected to the vertical pipe 9. The high-temperature steam flows in the cavity 17, transferring heat to the sludge on the surface of the drying plate through the wall of the drying plate. After releasing heat, the steam flows into the vertical pipe 9 on the right side through the air guide pipe II18 on the right side, and finally exits from the air guide pipe I10 on the right side for recycling. S2. The sludge slurry falling on the uppermost drying tray 12 is pushed by the rotating baffle 22. Due to the orientation of the baffle 22 above the upper drying tray 12, the sludge slurry is gradually scraped from the outer edge of the upper drying tray 12 towards the center. During the scraping process, the sludge slurry comes into full contact with the heated tray surface, and the water in it evaporates due to the heat. When the sludge slurry is pushed to the discharge hole 14 opened in the center of the upper drying tray 12, under the continuous pushing action of gravity and the baffle 22, it falls through the discharge hole 14 to the top surface of the lower drying tray 16 located directly below it. S3. The orientation of the baffle plate 22 above the lower drying tray 16 is opposite to that of the baffle plate 22 above the upper drying tray 12. They push the sludge slurry falling on the lower drying tray 16 from the center to the outer edge. The sludge slurry continues to be heated and dried on the lower drying tray 16 and moves radially. Finally, it falls from the outer edge of the lower drying tray 16 and falls onto the upper drying tray 12 below. This process is repeated. The sludge slurry moves from top to bottom between the upper drying tray 12 and the lower drying tray 16. Each time it passes through a drying tray, it is fully heated and turned. The water evaporates continuously, and the sludge slurry gradually dries and finally forms dry solid particles that fall into the bottom of the shell 1. S4. During the process of the sludge slurry being pushed by the step-by-step feeding mechanism, if hardened sludge clumps appear in the material, the arc-shaped plate 27 on one side of the feeding plate 22 and the hemispherical block 28 on it will apply downward squeezing force to the hardened clumps as the feeding plate 22 rotates, and initially crush them. If a large or hard foreign object is encountered, the feeding plate 22 will be subjected to a large reverse resistance. This resistance will overcome the elastic force of the torsion spring 25 on the fixed shaft 23, causing the feeding plate 22 to rotate backward around the fixed shaft 23 as the center, thereby clearing the foreign object and avoiding rigid impact and wear on the feeding plate 22 or the surface of the upper drying disc 12. After the feeding plate 22 passes the foreign object, under the restoring force of the torsion spring 25, the feeding plate 22 rotates in the opposite direction to reset until it is blocked by the limit plate 26 and returns to its normal working angle. S4. During the process of the plow plate 22 retracting and rotating due to encountering a hard foreign object, the plowing mechanism is triggered. The tilt of the plow plate 22 causes the lead ball 40, which was originally located in the groove 38, to roll along the second inclined surface 39, cross the gap, and enter the fixed box 36. After the lead ball 40 enters the fixed box 36, its gravity acts on the fixed box 36, causing the lifting plate 29 to move downward against the elastic force of the spring 32. When the lifting plate 29 moves downward, it drives the rake nail 35 to move downward together through the slide 34, so that the tip of the rake nail 35 extends downward from the preset through hole on the arc plate 27. At this time, although the plow plate 22 is in a tilted avoidance state, the tip of the rake nail 35 extends downward from the preset through hole on the arc plate 27. The rake nail 35 continues to rotate with the lever plate 22 under the drive of the support arm 20. Its tip can contact the hard foreign object and use the rotational force to plow or cut it. When the lever plate 22 completely passes the hard foreign object and is no longer blocked, it returns to the vertical state under the action of the torsion spring 25. During this process, the fixed box 36 returns to the vertical state with the lever plate 22, and the lead ball 40 inside rolls along the first inclined surface 37 and returns to the groove 38 after crossing the gap. After losing the gravity of the lead ball 40, the lifting plate 29 returns to the vertical state under the push of the spring 32, driving the rake nail 35 to retract into the arc plate 27, waiting for the next trigger. S5. Throughout the drying process, the air guiding mechanism operates continuously. The rotation of the hollow shaft 7 drives the turbine blades 45 on its outer wall to rotate at high speed within the conical tube 42. The rotation of the turbine blades 45 generates centrifugal suction, creating a localized negative pressure inside the conical tube 42. Simultaneously, the flared shape of the conical tube 42, wider at the bottom than the top, works in conjunction with the rotation of the turbine blades 45 to create a Venturi effect in the region of the conical tube 42, further enhancing the negative pressure effect. Under the attraction of this negative pressure, the sludge evaporated during the drying process... The hot, humid steam is rapidly drawn into the annular space between the conical tube 42 and the hollow shaft 7, and enters the internal cavity of the hollow shaft 7 through the air inlet 43 on the tube wall. Since the top of the exhaust pipe 46 is connected to the external negative pressure equipment, the inside of the hollow shaft 7 is always under negative pressure. Therefore, the humid steam entering the hollow shaft 7 is immediately drawn upward and discharged to the outside of the shell 1 through the exhaust pipe 46. This process enables the water vapor generated during drying to be quickly and forcibly discharged from the vicinity of the source, effectively preventing the steam from rising, diffusing and condensing inside the equipment. S6. After drying in multiple drying trays, the dried sludge particles fall into the bottom of the shell 1. As the hollow shaft 7 rotates, the arc-shaped material-pushing plate 48 fixed at its bottom slides on the inner wall of the bottom of the shell 1, scraping the accumulated dry sludge. Since the arc-shaped material-pushing plate 48 is curved and its center of curvature points to the position of the discharge pipe 44, the scraped dry sludge will converge along the surface of the arc-shaped material-pushing plate 48 towards the center area with the largest curvature. When the convergence point coincides with the inlet of the discharge pipe 44, the dry sludge is continuously discharged out of the machine through the discharge pipe 44, completing the entire drying process.

[0043] To ensure the long-term stable operation of the equipment and extend its service life, the following regular maintenance is recommended: 1. Daily Inspection: Check the surface scaling of the upper drying tray 12 and lower drying tray 16 and the operation of the feeding mechanism through the observation window 47 every day. At each shift, apply high-temperature resistant grease to the connection points of each moving part, such as the bearing connecting the support arm 20 and the hollow shaft 7, and the mating surface between the slide rod 31 and the fixed seat 30, through the external lubrication points.

[0044] 2. Regular cleaning: Every week during operation, the machine should be stopped to inspect and clean the air inlet 43 on the hollow shaft 7 to prevent dust accumulation from clogging the air intake and affecting the air guiding efficiency. At the same time, check the wear of the rake nails 35; if the wear is severe, they should be replaced in time.

[0045] 3. Quarterly Maintenance: Every quarter, open the top cover 6 or the side inspection door to manually clean stubborn scale on the surface of the drying trays, and check the fatigue condition of the torsion spring 25 and spring 32. Replace them if necessary to ensure the reliability of the material feeding and crushing mechanism. The structural design of this device fully considers the convenience of maintenance, allowing the top cover 6 to be disassembled for inspection of internal components when necessary.

[0046] However, as is well known to those skilled in the art, the working principle and wiring method of the drive motor 4 are conventional means or common knowledge, and will not be described in detail here. Those skilled in the art can make any selections according to their needs or convenience.

[0047] The accompanying drawings in this application are for illustrative purposes only. The dimensions and shapes of the components shown are not actual limitations but are merely schematic representations. In actual implementation, the components can be reasonably configured and adjusted according to specific needs and actual conditions.

[0048] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A disc dryer for treating coking wastewater, characterized in that, include: The housing (1) has a top cover (6) on its top. A hollow shaft (7) is rotatably disposed between the bottom inner wall of the housing (1) and the top inner wall of the top cover (6); Multiple upper drying discs (12) and lower drying discs (16) are arranged longitudinally and alternately inside the housing (1). The upper drying discs (12) are located above the lower drying discs (16), and the upper drying discs (12) are provided with discharge holes (14). A heating mechanism, located inside the housing (1), is used to dry the sludge slurry; A step-by-step feeding mechanism is located above each of the upper drying discs (12) and the lower drying discs (16) and rotates with the hollow shaft (7) to convey sludge slurry step by step downwards. as well as A gas guiding mechanism is used to discharge steam from the housing (1) during the drying process; The step-by-step feeding mechanism located above the upper drying tray (12) pushes the sludge slurry from the outside to the inside and discharges it through the discharge hole (14) to the adjacent lower drying tray (16). The step-by-step feeding mechanism located above the lower drying tray (16) pushes the sludge slurry from the inside to the outside and discharges it through the edge of the lower drying tray (16) to the adjacent upper drying tray (12).

2. A disc dryer for treating coking wastewater according to claim 1, characterized in that, The heating mechanism includes two vertical pipes (9) fixed on both sides of the housing (1), two air guide pipes I (10) and multiple air guide pipes II (18). The two air guide pipes I (10) are fixedly connected to the two vertical pipes (9) respectively. The upper drying plate (12) and the lower drying plate (16) are provided with cavities (17). One end of the air guide pipe II (18) is fixedly connected to the vertical pipe (9), and the other end extends into the corresponding cavity (17) to heat up the upper drying plate (12) and the lower drying plate (16) to dry the sludge.

3. A disc dryer for treating coking wastewater according to claim 2, characterized in that, The step-by-step feeding mechanism includes a fixed ring (19) fixed to the outer wall of the hollow shaft (7), a support arm (20) fixed to the fixed ring (19), and a dial plate (22) rotatably connected to the support arm (20) via a fixed shaft (23). A torsion spring (25) is sleeved on the fixed shaft (23). The two ends of the torsion spring (25) are respectively connected to the support arm (20) and the dial plate (22). A limiting plate (26) is fixed at the bottom of the support arm (20) to limit the reset rotation position of the dial plate (22).

4. A disc dryer for treating coking wastewater according to claim 3, characterized in that, The step-by-step feeding mechanism also includes an arc-shaped plate (27) fixed on the side of the feeding plate (22) near the fixed ring (19). The arc-shaped plate (27) is provided with a plurality of hemispherical blocks (28) for crushing the dry and hardened mud. When the feeding plate (22) rotates to scrape the material, the arc-shaped plate (27) crushes the dry and hardened scale, and when it encounters hard foreign objects, the feeding plate (22) rotates to avoid them.

5. A disc dryer for treating coking wastewater according to claim 4, characterized in that, It also includes a plowing mechanism, which includes a lifting plate (29) slidably connected to one side of the lever plate (22), a fixed seat (30) fixed on the lever plate (22), a sliding rod (31) slidably passing through the fixed seat (30) and fixed at the top end to the lifting plate (29), and a spring (32) sleeved on the sliding rod (31) and located between the fixed seat (30) and the lifting plate (29). The bottom of the lifting plate (29) is connected to a rake nail (35) through a sliding seat (34), and the bottom end of the rake nail (35) slidably passes through the arc plate (27).

6. A disc dryer for treating coking wastewater according to claim 5, characterized in that, The plowing mechanism also includes a fixed box (36) fixed to the top of the lifting plate (29) and a groove (38) provided on the lever plate (22). The bottom inner wall of the fixed box (36) is provided with a first inclined surface (37), and the bottom inner wall of the groove (38) is provided with a second inclined surface (39). A lead ball (40) is provided in the groove (38). When the lever plate (22) rotates and tilts, the lead ball (40) rolls into the fixed box (36) and drives the lifting plate (29) to move down, so that the rake nail (35) extends out of the arc plate (27) to plow hard foreign objects. When the lever plate (22) is reset, the lead ball (40) rolls back to the groove (38) under the action of the first inclined surface (37), and the lifting plate (29) is reset under the action of the spring (32).

7. A disc dryer for treating coking wastewater according to claim 6, characterized in that, The air guiding mechanism includes a tapered tube (42) fixed to the bottom of the upper drying plate (12) and the lower drying plate (16). The tapered tube (42) is sleeved on the outer wall of the hollow shaft (7) and its top inner diameter is smaller than its bottom inner diameter. The hollow shaft (7) is provided with an air inlet (43) located in the tapered tube (42). The outer wall of the hollow shaft (7) is fixed with a turbine blade (45) located in the tapered tube (42). The top cover (6) is fixed with an exhaust pipe (46) connected to an external negative pressure device. The bottom end of the exhaust pipe (46) extends into the hollow shaft (7). The hollow shaft (7) drives the turbine blade (45) to rotate, forming a negative pressure in the tapered tube (42), drawing moisture into the hollow shaft (7) through the air inlet (43) and discharging it through the exhaust pipe (46).

8. A disc dryer for treating coking wastewater according to claim 7, characterized in that, The bottom of the housing (1) is fixed with a plurality of rigid legs (2), and a mounting plate (3) is fixed between the plurality of rigid legs (2). A drive motor (4) is fixed on the mounting plate (3). A gearbox (5) is fixed on the bottom of the housing (1). The output shaft of the drive motor (4) is fixedly connected to the input shaft of the gearbox (5). The output end of the gearbox (5) is fixedly connected to the bottom end of the hollow shaft (7) for driving the hollow shaft (7) to rotate.

9. A disc dryer for treating coking wastewater according to claim 8, characterized in that, The housing (1) is fixed with a plurality of fixing plates I (11) for supporting the upper drying tray (12) and a plurality of fixing plates II (15) for supporting the lower drying tray (16). Fixing plates I (11) are fixedly connected to the upper drying tray (12) by bolts, and fixing plates II (15) are fixedly connected to the lower drying tray (16) by bolts. The outer wall of the upper drying tray (12) is fixed with a skirt (13) to prevent mud from falling from its edge.

10. A disc dryer for treating coking wastewater according to claim 9, characterized in that, The bottom of the housing (1) is fixed with a discharge pipe (44), and the outer wall of the hollow shaft (7) is fixed with a plurality of arc-shaped material-pushing plates (48) that slide against the inner wall of the bottom of the housing (1). The arc center of the arc-shaped material-pushing plate (48) corresponds to the position of the discharge pipe (44) and is used to gather and discharge the dried mud to the discharge pipe (44).

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