Vertical disc dryer

Abstract

The utility model discloses a vertical disc dryer, solve the uneven sludge drying, low drying efficiency problem in the prior art. The utility model discloses a cylinder and support, the cylinder is equipped with the shaft and a plurality of heating disc body, the axle passes through the heating disc body, be equipped with a plurality of harrow hand subassembly on the axle, and the harrow hand subassembly is correspondingly set with heating disc body, and the upper portion of axle is rotatably connected with the upper support that sets at the top of cylinder, and the lower part of axle passes through the lower support that sets at the bottom of cylinder and is connected with the drive assembly transmission that sets on the support, the utility model discloses a heating disc piece passes on the heat transfer to material, and the moisture in evaporation material, thereby realizes the drying of material. In the working process, the dryer makes the harrow hand rotate constantly through the transmission system, and the material forms the thin layer on the disc piece, and accepts the heat from the disc piece surface. With the rotation of harrow hand, the material moves on the disc piece surface constantly, so that every part of material can be heated evenly, avoids the situation of partial overheating or not drying to happen.

Description

Technical Field

[0001] This utility model relates to the fields of wastewater treatment and environmental technology, and in particular to a dryer. Background Technology

[0002] Currently, the commonly used sludge treatment technologies internationally include land application, landfill, and incineration. Due to land scarcity and other environmental pollution problems, especially in large cities, the proportion of sludge treated through land application and landfill is gradually decreasing, while the proportion of incineration is increasing, gradually becoming one of the main sludge treatment methods in developed countries. Drying and incineration has become a mature technology in developed countries such as Europe and the United States. While my country has extensive practical experience in this field, it mainly focuses on exploring the principles of sludge drying and incineration; the development, research, and application of specialized equipment are still in the development stage. Therefore, it is necessary to research and develop high-tech, economically viable, efficient, and safe drying and incineration technologies and equipment suitable for my country's national conditions, based on absorbing advanced foreign technologies and experiences.

[0003] With rapid industrialization and urbanization, the number and treatment capacity of wastewater treatment plants have continuously increased, resulting in the generation of large amounts of sludge as a byproduct of wastewater treatment. Statistics show that sludge typically has a water content exceeding 80%. Without effective dewatering and drying, it not only occupies significant land resources but also causes serious environmental pollution. Furthermore, sludge contains large amounts of organic matter, heavy metals, pathogenic microorganisms, and other harmful components. Direct landfilling or dumping can lead to soil pollution, groundwater pollution, and air pollution. Therefore, rational and efficient sludge treatment technologies have become one of the important research directions in the field of environmental protection.

[0004] Sludge drying is a crucial step in sludge treatment, significantly reducing its moisture content, volume, transportation and disposal costs, and improving resource utilization. Sludge drying technologies mainly include natural drying, thermal drying, and freeze drying, with thermal drying being widely used due to its fast drying speed and large processing capacity. However, traditional sludge drying equipment still suffers from several problems, such as high energy consumption, uneven drying, complex equipment structure, and high maintenance costs. Therefore, optimizing the structural design of sludge disc dryers to improve heat transfer efficiency, reduce energy consumption, and enhance equipment stability and durability is the main objective of this research. Utility Model Content

[0005] To address the shortcomings in the aforementioned background technology, this utility model proposes a vertical disc dryer, which solves the problems of uneven sludge drying and low drying efficiency in the prior art.

[0006] The technical solution of this utility model is implemented as follows: A vertical disc dryer includes a cylinder and a support for supporting the cylinder. A rotating shaft and several heating discs are provided inside the cylinder. The rotating shaft passes through the heating discs and is provided with several rake assemblies. The rake assemblies are correspondingly arranged with the heating discs. The upper part of the rotating shaft is rotatably connected to an upper support member set at the top of the cylinder, and the lower part of the rotating shaft passes through a lower support member set at the bottom of the cylinder and is connected to a drive assembly set on the support for transmission; ensuring stable transmission and reducing transmission energy loss.

[0007] The rake assembly includes a central ring sleeve connected to a rotating shaft. N connecting posts (N≥3) are arranged at equal angles on the outer ring of the central ring sleeve. Each connecting post has at least one rake arm, and each rake arm has several rake handles. Inside the dryer, a heat source (usually steam or hot oil) heats the heating disc, generating heat on its surface. The sludge is evenly distributed onto the heating disc via a feeding device. Under the rotation of the multiple rake handles in the rake assembly, the material is evenly spread on the heating disc for uniform heating, ensuring uniform drying of the sludge and effectively preventing overheating and clumping.

[0008] Further optimized, the rake includes a rake claw support and rake claws. The rake claws are equipped with connecting studs, which engage with positioning holes on the rake claw support and are secured to the support by double nuts. By rotating the connecting studs, the angle of the rake claws is changed, enabling the rake assembly to continuously stir, tumble, and push the material as it rotates with the shaft, ensuring uniform heating and efficient material delivery.

[0009] Further optimization involves using a V-shaped rake claw support, which is fixed to the rake arm; the central ring is connected to the rotating shaft via a key to ensure connection stability.

[0010] Further optimization involves having two parallel rake arms on a connecting column, with the rake handles on the two rake arms arranged in a cross pattern; this increases the mixing area, allowing the material to be tumbled twice, increasing the drying area and improving drying efficiency.

[0011] Further optimized, the heating plate is fixed inside the cylinder by a support frame. The heating plate includes a large plate and a small plate, which are alternately arranged along the rotating shaft. A flow channel is provided at the center of the large plate, and a baffle ring is provided at the outer edge of the large plate. The alternating arrangement of the large and small plates along the rotating shaft increases the drying area and improves the drying efficiency while achieving self-unloading.

[0012] Further preferably, both the large and small discs are hollow, forming an inner cavity; the cylinder includes an upper cylinder and a lower disc, which are connected by flange bolts; the lower disc is also hollow, forming an inner cavity. Preferably, the cylinder is equipped with an inlet heat riser and an outlet heat riser; both the inlet and outlet heat risers communicate with the inner cavity. The heat source (usually steam or hot oil) enters the large, small, and lower discs through the inlet heat riser, ensuring uniform heating of the discs and guaranteeing uniform heating of the sludge.

[0013] Further optimization involves a feed inlet and a vent at the top of the cylinder, and a discharge outlet at the bottom. The feed inlet is connected to a screw conveyor via a guide pipe. The screw conveyor lifts the sludge to the feed inlet and then onto the heating plate, thus achieving feeding. The vent is used for the timely removal of moisture.

[0014] In a further preferred embodiment, the upper support component includes an upper support sleeve, which is fixedly connected to an upper flange bushing located at the top of the cylinder. The rotating shaft passes upward through the upper flange bushing and the upper support sleeve in sequence. A sealing element is provided between the upper flange bushing and the rotating shaft, and a bearing element is provided between the upper support sleeve and the rotating shaft. This structural design ensures the sealing performance of the cylinder while guaranteeing the stability of the rotating shaft.

[0015] Further optimized, the lower support component includes a lower support sleeve, which is fixedly connected to a lower flange bushing located at the bottom of the cylinder. The rotating shaft passes downward through the lower flange bushing and the lower support sleeve in sequence. A sealing element is provided between the lower flange bushing and the rotating shaft, and a bearing element is provided between the lower support sleeve and the rotating shaft. This structural design ensures the sealing of the cylinder while guaranteeing the stability of the rotating shaft, thereby achieving efficient power transmission and reducing energy consumption.

[0016] The beneficial effects of this invention are as follows: This invention transfers heat to the material through heating discs, evaporating the moisture in the material and thus achieving material drying. During operation, the dryer uses a transmission system to continuously rotate the rake, causing the material to form a thin layer on the discs and receive heat from the disc surface. As the rake rotates, the material continuously moves on the disc surface, ensuring that every part of the material is heated evenly, avoiding localized overheating or undried conditions.

[0017] This utility model can be equipped with multiple rake arms 53, preferably two parallel ones, on the connecting column. The two rake arms are arranged one in front of the other, and the rake handles on the two front-to-back rake arms are arranged crosswise. This achieves double the number of disturbances within the same axial height. The two rows of rake handles are staggered by 1 / 2 pitch, turning the original one-time turning into two times. The material layer is instantly "cut" and then closed, realizing two turnings and two mixings, increasing the mixing area and the contact area with the heating plate, so that the drying is faster and more uniform.

[0018] In application, this invention can effectively remove moisture from sludge, significantly reduce sludge volume, and lower subsequent transportation and disposal costs. Through a suitable heating medium and control system, the disc dryer can complete the drying process at a relatively low temperature, thus avoiding excessive degradation or loss of organic components in the sludge. Furthermore, the continuous feeding and discharging function of the disc dryer greatly improves its efficiency in large-scale sludge treatment.

[0019] This utility model of a vertical disc dryer addresses the characteristics of high moisture content, high viscosity, and potential corrosivity of sewage treatment sludge. Through systematic adaptive design and economic optimization, it has become the preferred solution for the reduction, harmlessness, and resource utilization of sewage treatment sludge. It not only solves the technical problem of drying high-moisture materials, but also achieves the organic unity of environmental, economic, and social benefits; and has broad prospects for promotion and application. Attached Figure Description

[0020] To more clearly illustrate the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 for Figure 1 View from AA direction; Figure 3 for Figure 2 BB-direction view; Figure 4 for Figure 3 Enlarged view of a section at point C; Figure 5 for Figure 3 Enlarged view of a section at point D; Figure 6 This is a schematic diagram of the rake assembly structure; Figure 7 This is a schematic diagram of the rake structure in Example 2; Figure 8 This is a schematic diagram of the rake assembly in Example 3. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] Example 1, such as Figure 1 , 2 As shown, a vertical disc dryer includes a cylinder 1 and a support 2 for supporting the cylinder 1. Inside the cylinder 1, there is a rotating shaft 3 and several heating discs 4. The heating discs 4 remain relatively stationary with respect to the cylinder. The axis of the rotating shaft coincides with the center line of the cylinder. The rotating shaft 3 passes through the heating discs 4, and the material falls layer by layer onto the multiple heating discs, forming a thin material layer. This increases the contact area between the material and the heating surface, improving heat transfer efficiency. Several rake assemblies 5 are provided on the rotating shaft 3, corresponding to one heating disc 4. As the rotating shaft rotates, the rake assemblies continuously stir, turn, and push the material on the heating discs, ensuring uniform heating and avoiding localized overheating or uneven drying, significantly improving drying efficiency. The upper part of the rotating shaft 3 is rotatably connected to the upper support member 10 located at the top of the cylinder 1, and the lower part of the rotating shaft 3 passes through the lower support member 11 located at the bottom of the cylinder 1 and is connected to the drive assembly 12 located on the bracket 2. The upper and lower support members provide stable support for the rotating shaft, ensuring its stability during long-term operation and reducing vibration and wear. The drive assembly 12 is a motor, which drives the rotating shaft to rotate through a gear pair or belt-pulley. The rotation of the rotating shaft drives the rake assembly to rotate relative to the heating plate, so as to stir and spread the material on the heating plate, and then push the material downward to dry layer by layer. By adjusting parameters such as the temperature of the heating plate, the rotation speed of the rotating shaft, and the number and angle of the rake arms, the drying time, drying degree, and discharge speed of the material can be flexibly controlled to adapt to different material characteristics and drying requirements.

[0024] like Figure 6As shown, in this embodiment, the rake assembly 5 includes a central ring 51 connected to the rotating shaft 3. N connecting posts 52, where N ≥ 3, are arranged at equal angles on the outer ring of the central ring 51. At least one rake arm 53 is mounted on each connecting post 52, and several rake hands 54 are mounted on each rake arm 53. The rake hands 54 contact the material, undertaking the active stirring and pushing functions. The equally angled arrangement of the connecting posts ensures that the rake arms and rake hands experience more uniform force during rotation, improving the structural strength and operational stability of the rake assembly, while also enabling more uniform stirring and pushing of the material. The central ring is connected to the rotating shaft, and the connecting posts are equipped with rake arms and rake hands. This modular design makes the installation and disassembly of the rake assembly more convenient, facilitating maintenance and replacement. Multiple rake arms can be mounted on the connecting posts, and multiple rake hands can be mounted on each rake arm. This design allows for flexible adjustment of the density and arrangement of the rake hands according to the material characteristics and drying requirements to achieve the best drying effect.

[0025] The dryer transfers heat to the material via heating discs, evaporating the moisture and thus drying the material. During operation, the dryer's transmission system continuously rotates the rakes, causing the material to form a thin layer on the discs and receive heat from their surface. As the rakes rotate, the material moves across the disc surface, ensuring even heating of every portion and preventing localized overheating or undried areas. When the material is heated on the discs, the moisture on its surface begins to convert into steam. This steam is quickly carried away by the airflow system, preventing accumulation within the dryer and ensuring efficient heat transfer during the drying process.

[0026] Example 2, as Figure 7 As shown, a vertical disc dryer is further optimized based on Embodiment 1. In this embodiment, the rake 54 includes a rake claw support 541 and a rake claw 542. The rake claw support 541 can be fixed to the rake arm by welding. A connecting stud 543 is fixed on the rake claw 542. The connecting stud 543 mates with the positioning hole on the rake claw support 541 and is fixed to the rake claw support 541 by a double nut. The positioning hole is a smooth hole design, and the connecting stud is fixed to the rake claw support by a double nut consisting of upper and lower nuts. The stirring angle of the rake claw can be adjusted by rotating the connecting stud, so that the rake claw can both ensure large-area stirring and push the material to the next heating plate. The rake claw is a thin-walled wear-resistant casting; the rake claw support is a thick-walled carbon steel part. Only the rake claw needs to be replaced, not the support, which significantly reduces spare parts costs. After the double nuts are loosened, the rake claw can be pulled out as a whole without disassembling the rake arm, reducing replacement time. The connecting stud and the positioning hole adopt a small clearance fit of H7 / f6, and are further tightened by double nuts. The radial runout of the rake claw is ≤0.2 mm, which avoids the impact on the cylinder caused by "claw swinging" during high-speed rotation.

[0027] As a preferred embodiment, each connecting column 52 is equipped with a rake arm, with 4 or 5 rake handles on the rake arm corresponding to the large disc 41; and 3 rake handles on the rake arm corresponding to the small disc, preferably to completely cover the corresponding disc. The rake claw support 541 is a V-shaped frame, providing stable support for the rake claws. The V-shaped apex has no dead angles, preventing material accumulation. The V-shaped frame is fixed to the rake arm 53, and the fixed connection can be achieved by welding. The central ring 51 is connected to the rotating shaft 3 by a key; the key connection transmits bidirectional torque, and the rake handles have "zero slippage".

[0028] Example 3, as Figure 8 As shown, a vertical disc dryer is described. This embodiment differs from Embodiment 2 in that: in this embodiment, two parallel rake arms 53 are mounted on a connecting column 52, positioned one behind the other. The rake handles 54 on the two rake arms 53 are arranged crosswise. This achieves double the number of disturbances within the same axial height. The two rows of rake handles are staggered by 1 / 2 pitch, transforming the original one-time turning into two-time turning. The material layer is instantly "cut" and then brought back together, achieving two turnings and two mixings, increasing the mixing area and the contact area with the heating disc, resulting in faster and more uniform drying.

[0029] like Figure 3 As shown, in this embodiment, the heating plate 4 is fixed inside the cylinder 1 by a support frame 13. The outer ring of the support frame is welded to the cylinder wall, and the inner ring is only fixed to the outer edge of the plate. The heating plate 4 includes a large plate 41 and a small plate 42. The heating plate is the core part of the disc dryer and is usually composed of multiple circular metal plates. The plate surface is flat or slightly concave to enhance heat conduction efficiency. The large plate 41 and the small plate 42 are alternately and spaced along the axis of rotation 3. A flow channel 43 is provided at the center of the large plate 41. A baffle ring 44 is provided on the outer edge of the large plate 41. The flow channel is used for the downward flow of materials on the large plate, and the baffle ring prevents materials from scattering from the outer circle. Making the "alternating large and small plates + central flow channel" into an integral support frame module essentially solves the three things of "heating, material feeding, and gas distribution" in one go within the axial height, improving the evaporation intensity. The edge of the large plate has no notches, and the rake pushes all the materials towards the central hole; the small plate does the opposite, throwing the materials towards the outer ring. The drying tray can be emptied without tilting, resulting in zero waste of heating area and improved drying efficiency.

[0030] In this embodiment, both the large plate 41 and the small plate 42 are hollow, forming an inner cavity. The cylinder 1 includes an upper cylinder 101 and a lower plate 102, which are connected by flange bolts. The lower plate 102 is hollow, forming an inner cavity. This hollow cavity is equivalent to an additional "bottom heating plate," increasing the heating area. The cylinder 1 is equipped with an inlet heat riser 14 and an outlet heat riser 15, both of which communicate with the inner cavity. The heat source (usually steam or hot oil) enters the large, small, and lower plates through the inlet heat riser, ensuring uniform heating of the plates and guaranteeing uniform heating of the sludge.

[0031] In this preferred embodiment, the top of the cylinder 1 is provided with a feed inlet 7 and a vent 6, and the bottom of the cylinder 1 is provided with a discharge outlet 8. The feed inlet 7 is connected to the screw conveyor 17 through a guide pipe 16. The screw conveyor lifts the sludge to the feed inlet and drops it onto the heating plate, thus realizing feeding. The vent can be equipped with an exhaust fan to form a dehumidification system, which is responsible for collecting water vapor and moisture released during the drying process and discharging it through a pipe.

[0032] like Figure 4 As shown, in this embodiment, the upper support member 10 includes an upper support sleeve 10-1, which is fixedly connected to an upper flange bushing 10-2 located at the top of the cylinder 1. The rotating shaft 3 passes upward through the upper flange bushing 10-2 and the upper support sleeve 10-1 in sequence. A sealing element is provided between the upper flange bushing 10-2 and the rotating shaft 3, and a bearing element is provided between the upper support sleeve 10-1 and the rotating shaft 3. Figure 5 As shown, the lower support member 11 includes a lower support sleeve 111, which is fixedly connected to a lower flange bushing 112 located at the lower part of the cylinder 1. The rotating shaft 3 passes downward through the lower flange bushing 112 and the lower support sleeve 111 in sequence. A sealing element is provided between the lower flange bushing 112 and the rotating shaft 3, and a bearing element is provided between the lower support sleeve 111 and the rotating shaft 3. This structural design ensures the sealing of the cylinder while guaranteeing the stability of the rotating shaft, thereby achieving efficient power transmission and reducing energy consumption.

[0033] The specific working process of this utility model is as follows: Material is continuously fed from the top of the dryer (screw conveyor) onto the outer ring of the first heating disc. Under the mechanical action of the rotating rake and the action of the counter-mounted rake blades, the material tumbles and stirs, spreading in a serrated pattern across the entire disc surface, thus achieving contact heating and drying. Simultaneously, the material moves continuously from the outside inwards to the center channel. Then, the material falls from the inner edge onto the inner ring of the second heating disc, where it circulates from the inside out under the action of the forward-mounted rake blades, and falls from the outer edge onto the outer ring of the third heating disc. This process continues, with the material being heated and dried layer by layer from top to bottom. Finally, the material falls onto the lower disc and is continuously discharged from the bottom discharge port by the rake, resulting in a qualified dried product. Evaporated moisture is discharged from the upper outlet or drawn out of the system by a fan. Furthermore, the disc dryer also has an airflow system that carries away the moisture evaporated from the sludge surface through the exhaust system, ensuring a smooth drying process. Because of its ability to continuously feed and discharge, the disc dryer is suitable for large-scale sludge treatment and can maintain a relatively stable working state.

[0034] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A vertical disc dryer, comprising a cylinder (1) and a support (2) for supporting the cylinder (1), wherein a rotating shaft (3) and a plurality of heating discs (4) are provided inside the cylinder (1), the rotating shaft (3) passing through the heating discs (4), characterized in that: The rotating shaft (3) is provided with several rake components (5), which are correspondingly arranged with the heating plate (4). The upper part of the rotating shaft (3) is rotatably connected to the upper support (10) set on the top of the cylinder (1), and the lower part of the rotating shaft (3) passes through the lower support (11) set at the bottom of the cylinder (1) and is connected to the drive component (12) set on the bracket (2). The rake assembly (5) includes a central ring (51) connected to the rotating shaft (3). N connecting posts (52) are provided at equal angles on the outer ring of the central ring (51), where N≥3. At least one rake arm (53) is provided on the connecting post (52), and several rake hands (54) are provided on the rake arm (53).

2. The vertical disc dryer according to claim 1, characterized in that: The rake (54) includes a rake claw bracket (541) and a rake claw (542). The rake claw (542) is provided with a connecting stud (543). The connecting stud (543) is matched with a positioning hole provided on the rake claw bracket (541) and is fixed on the rake claw bracket (541) by a double nut.

3. The vertical disc dryer according to claim 2, characterized in that: The rake claw support (541) is a V-shaped frame, which is fixed on the rake arm (53); the central ring (51) is connected to the rotating shaft (3) by a key.

4. The vertical disc dryer according to claim 1, characterized in that: Two parallel rake arms (53) are provided on a connecting column (52), and the rake handles (54) on the two rake arms (53) are arranged crosswise.

5. The vertical disc dryer according to any one of claims 1 to 4, characterized in that: The heating plate (4) is fixed inside the cylinder (1) by a support frame (13). The heating plate (4) includes a large plate (41) and a small plate (42). The large plate (41) and the small plate (42) are alternately and spaced along the axis of rotation (3). A flow channel (43) is provided at the center of the large plate (41), and a baffle ring (44) is provided on the outer edge of the large plate (41).

6. The vertical disc dryer according to claim 5, characterized in that: Both the large disc (41) and the small disc (42) are hollow to form an inner cavity; the cylinder (1) includes an upper cylinder (101) and a lower disc (102), which are connected by flange bolts; the lower disc (102) is hollow to form an inner cavity.

7. The vertical disc dryer according to claim 6, characterized in that: The cylinder (1) is provided with an inlet heat riser (14) and an outlet heat riser (15); both the inlet heat riser (14) and the outlet heat riser (15) are connected to the inner cavity.

8. The vertical disc dryer according to any one of claims 1 to 4, 6 and 7, characterized in that: The top of the cylinder (1) is provided with a feed inlet (7) and a vent (6), and the bottom of the cylinder (1) is provided with a discharge outlet (8). The feed inlet (7) is connected to the screw conveyor (17) through a guide pipe (16).

9. The vertical disc dryer according to claim 8, characterized in that: The upper support member (10) includes an upper support sleeve (10-1), which is fixedly connected to an upper flange bushing (10-2) located at the top of the cylinder (1). The rotating shaft (3) passes through the upper flange bushing (10-2) and the upper support sleeve (10-1) in sequence. A sealing element is provided between the upper flange bushing (10-2) and the rotating shaft (3), and a bearing element is provided between the upper support sleeve (10-1) and the rotating shaft (3).

10. The vertical disc dryer according to claim 9, characterized in that: The lower support member (11) includes a lower support sleeve (111), which is fixedly connected to a lower flange bushing (112) located at the lower part of the cylinder (1). The rotating shaft (3) passes through the lower flange bushing (112) and the lower support sleeve (111) in sequence. A sealing element is provided between the lower flange bushing (112) and the rotating shaft (3), and a bearing element is provided between the lower support sleeve (111) and the rotating shaft (3).

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