Chemical fertilizer raw material drying device
By adopting an axial through-type design, electric heating tubes, staggered spiral structure, and detachable sealed end cap assembly in the fertilizer raw material drying device, the problems of uneven heat distribution, uneven material mixing, and insufficient sealing are solved, achieving an efficient and uniform fertilizer drying process and convenient equipment maintenance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HUNAN DUGAO BIOTECHNOLOGY CO LTD
- Filing Date
- 2025-05-06
- Publication Date
- 2026-04-10
AI Technical Summary
Existing fertilizer raw material drying equipment suffers from problems such as uneven heat distribution, uneven material mixing, insufficient sealing, and inconvenient maintenance, which affect fertilizer quality and production efficiency.
The cylinder features an axially continuous design with electric heating tubes arranged circumferentially on the outer wall and covered with an insulation layer. Combined with a stirring structure featuring alternating forward spiral blades and reverse spiral guide plates, and equipped with a detachable sealing end cap assembly, including a dovetail groove guide rail and a trapezoidal elastic sealing ring, a dynamic interference seal is formed.
It achieves efficient and uniform drying of fertilizer raw materials, reduces particle breakage, improves sealing performance and ease of maintenance, and enhances the operating efficiency and service life of the equipment.
Smart Images
Figure CN224108529U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to a chemical fertilizer production equipment technical field, concretely relates to a chemical fertilizer raw material drying device. BACKGROUND
[0002] In the chemical fertilizer production process, drying treatment is an important link for chemical fertilizer raw materials. The existing chemical fertilizer raw material drying device has some deficiencies, for example:
[0003] Drying efficiency and heat distribution problems: due to the unreasonable heating mode and structure design, part of the drying device causes uneven heat distribution, and local overheating phenomenon is easy to appear, so that the chemical fertilizer particle carbonization, the product quality is affected. At the same time, heat loss is large, and energy utilization efficiency is not high.
[0004] Material mixing and fluidity problems: the mixing effect of traditional stirring structure is poor, and the material stays for different time in the drying cavity, so that the drying uniformity is poor. Moreover, in the stirring process, the particle is easy to break due to mechanical stirring, and the quality of chemical fertilizer is affected.
[0005] Sealing and maintenance problems: the sealing structure of some drying devices is not perfect, and in the long-term use process, sealing failure is easy to appear, leading to heat loss and dust leakage, which not only affects the drying effect, but also pollutes the working environment. In addition, the design of sealing structure is not conducive to the cleaning and maintenance of equipment, increases the maintenance cost and downtime of equipment.
[0006] Therefore, a new type of chemical fertilizer raw material drying device needs to be designed to solve the problems in the prior art. UTILITY MODEL CONTENT
[0007] Therefore, the utility model provides a chemical fertilizer raw material drying device, which aims at solving the problems of the existing drying device in drying efficiency, heat distribution, material mixing and fluidity and sealing and maintenance, realizing efficient drying, optimizing heat distribution, enhancing mixing and fluidity and improving sealing and maintenance convenience.
[0008] The utility model discloses the purpose that is realized through the following technical schemes:
[0009] The utility model provides a kind of chemical fertilizer raw material drying device, including cylinder, heating assembly, stirring assembly and sealing end cap assembly, the inside of the cylinder forms axial through drying chamber, and the both ends of the drying chamber are equipped with feed inlet and discharge outlet respectively;Heating assembly is arranged around the outer wall of the cylinder, and the heating assembly includes electric heating pipe distributed along the circumference of cylinder and the heat preservation layer covered in the outer layer of electric heating pipe;Stirring assembly is coaxially arranged in the drying chamber, including main stirring shaft, positive helical blade fixed to the surface of main stirring shaft, the inner wall of the cylinder is equipped with reverse helical guide plate with the opposite rotation direction of positive helical blade, and the installation position of the reverse helical guide plate forms staggered distribution with the helical trajectory of positive helical blade, forms convection shear effect to reduce particle breakage;Sealing end cap assembly includes bearing and end cap structure detachably connected to the both ends of cylinder, and the end cap structure includes bottom cover connected with cylinder by screw thread, sealing inner ring inserted in the inner side of bottom cover by dovetail groove guide rail from outside to inside, one side of the sealing inner ring towards the inside of cylinder is equipped with trapezoidal section elastic sealing ring, and the elastic sealing ring generates radial expansion deformation under the action of axial compression force and forms interference seal with the inner wall of cylinder.
[0010] The chemical fertilizer raw material drying device has excellent performance, and can achieve multiple goals such as efficient drying, optimized heat distribution, improved mixing and fluidity, improved sealing, and convenient maintenance.
[0011] In terms of efficient drying and optimized heat distribution, the cylinder is designed to be axial through, and the electric heating pipes are uniformly arranged on the outer wall. At the same time, the heat preservation layer tightly covers the electric heating pipes, greatly reducing heat loss. The series of ingenious designs work together to enable uniform heat conduction in the drying cavity, effectively avoiding local overheating, thereby eliminating the problem of carbonization of fertilizer particles due to overheating, and ensuring efficient and stable drying process.
[0012] In terms of mixing and fluidity enhancement, the device innovatively adopts a unique structure of staggered distribution of positive helical blades and reverse helical guide plates. This careful design promotes strong convection and shear effect of the material in the drying cavity, significantly prolonging the residence time of the material. In this way, the material can be more fully contacted with hot air, and the uniformity of drying is improved in all directions. Moreover, this structure effectively reduces the impact force suffered by the particles during mechanical stirring, greatly reduces the possibility of particle breakage, and ensures the quality of the chemical fertilizer raw material.
[0013] The design of the sealing end cover assembly is ingenious in terms of sealing performance and maintenance convenience. It uses dovetail slot guide rail insertion structure and is matched with trapezoidal elastic sealing ring. During the operation of the equipment, the trapezoidal elastic sealing ring can produce radial expansion deformation under the action of axial compression force, thereby forming a reliable dynamic interference seal with the inner wall of the cylinder. This sealing method can perfectly adapt to the thermal expansion and contraction conditions caused by temperature changes, ensuring the sealing performance during the drying process. More importantly, the detachable design of the sealing end cover assembly is unique and greatly facilitates the cleaning and maintenance of the equipment interior, effectively reduces the maintenance cost of the equipment, and improves the service life and operation efficiency of the equipment.
[0014] Preferably, the material-approaching side edge of the reverse helical guide plate is provided with an auxiliary stirring tooth extending towards the center of the drying chamber, and the extension direction of the auxiliary stirring tooth forms an acute angle with the helical direction of the reverse helical guide plate.
[0015] The auxiliary stirring tooth extends towards the center of the drying chamber, which can break the adhesion layer of the material on the surface of the guide plate and strengthen the rolling of the particles; the design of the acute angle forms local turbulence, which accelerates the escape of moisture, and is especially suitable for high-humidity raw material pretreatment. The extension direction of the stirring tooth is complementary to the helical direction of the guide plate, which reduces the accumulation of material at the edge of the guide plate and reduces the frequency of shutdown cleaning.
[0016] Preferably, the top surface of the auxiliary stirring tooth is a wedge-shaped structure, and the wedge-shaped tip thereof faces the rotation direction of the cylinder; the inclined surface of the wedge-shaped structure forms a parallel gap with the advancing surface of the forward helical blade.
[0017] The wedge-shaped tip faces the rotation direction, which reduces the resistance of the material passing through, and at the same time, the parallel gap between the inclined surface and the helical blade forms a continuous shear band, which improves the crushing efficiency and avoids excessive extrusion of the particles. The wedge-shaped structure guides the airflow to rise along the inclined surface, enhances the convection of hot air in the drying chamber, and shortens the drying period.
[0018] Preferably, the helical pitch angle of the reverse helical guide plate is smaller than the helical pitch angle of the forward helical blade.
[0019] The smaller reverse helical pitch angle increases the resistance of the guide plate to the material, prolongs the residence time of the material in the high-temperature zone, and is suitable for deep dehydration of high-moisture raw materials. The large pitch angle of the forward helical blade ensures the axial advancing efficiency, and the small pitch angle of the reverse guide plate forms a dynamic resistance balance, reducing the motor load fluctuation.
[0020] Preferably, the surface of the reverse helical guide plate is provided with an arc-shaped transition part connected with the inner wall of the cylinder, and the inner wall of the cylinder is provided with a semispherical protrusion, and the curvature of the arc-shaped transition part matches the spherical curvature of the semispherical protrusion.
[0021] The arc-shaped transition part reduces the material retention at the connecting part of the guide plate and the cylinder, and prevents uneven drying caused by local material accumulation; the staggered distribution of the semispherical protrusions and the mechanical support formed by the transition part of the guide plate reduce the risk of deformation of the guide plate due to thermal stress.
[0022] Preferably, the inner side end surface of the bottom cover is provided with an annular groove, the outer periphery of the sealing inner ring is provided with a flange matched with the annular groove, and a pressure sensing assembly is arranged between the bottom surface of the flange and the annular groove.
[0023] The elastic contact head feeds back the pressing force of the sealing inner ring through the compression amount, the signal processing circuit board can early warn the sealing failure, and prevents heat loss or dust leakage caused by loose sealing during the drying process. The matched design of the annular groove and the flange allows the sealing inner ring to be slightly adjusted in position under thermal expansion, and ensures that the elastic sealing ring is continuously and effectively contacted.
[0024] Preferably, the top of the elastic contact head is a spherical cap contact surface, the bottom surface of the flange is provided with an arc-shaped guide groove which is complementary in shape to the spherical cap contact surface, and the compression stroke direction of the elastic contact head is consistent with the axial movement direction of the sealing inner ring.
[0025] The spherical cap contact surface and the guide groove are complementary in shape, reducing the eccentric wear of the contact head during axial movement and prolonging the service life of the sensor; the compression stroke direction is consistent with the movement direction of the sealing inner ring, ensuring that the pressure signal truly reflects the sealing state and avoiding false alarms.
[0026] Preferably, the semispherical protrusions are staggered distributed on the inner wall of the cylinder, forming at least two rows of axially extending protrusion arrays, and the projection positions of each row of protrusion arrays correspond to the spiral gap regions of the reverse helical guide plate.
[0027] The staggered protrusion arrays form secondary vortexes in the gap regions of the guide plate, enhancing the contact area of the material and hot air and improving the thermal efficiency; the spherical surface structure of the protrusions reduces material adhesion, and cooperates with the stirring assembly to realize self-cleaning of the inner wall of the cylinder.
[0028] Preferably, the plurality of elastic contact heads are uniformly distributed along the annular groove.
[0029] The uniformly distributed contact heads can comprehensively monitor the pressing force of the sealing inner ring in all directions, avoiding deformation and failure of the sealing ring caused by local overload; the multi-point monitoring improves the reliability of the system, and the sealing state can still be evaluated through the remaining contact heads when a single contact head fails.
[0030] Compared with the prior art, the utility model has the beneficial effects that:
[0031] The chemical fertilizer raw material drying device has excellent performance, can achieve multiple goals of efficient drying, heat distribution optimization, mixing and flow enhancement, sealing improvement and convenient maintenance, etc.
[0032] In terms of efficient drying and heat distribution optimization, the cylinder adopts axial through design, and the electric heating pipes are uniformly arranged on the outer wall in the circumferential direction. At the same time, the heat preservation layer tightly covers the electric heating pipe, greatly reducing the heat loss. The series of ingenious designs work together to enable the heat to be uniformly conducted in the drying cavity, effectively avoiding local overheating, thereby eliminating the problem of carbonization of chemical fertilizer particles due to overheating, and ensuring the efficiency and stability of the drying process.
[0033] In terms of mixing and flow enhancement, the device innovatively adopts a unique structure of staggered distribution of forward spiral blades and reverse spiral guide plates. This careful design promotes the formation of strong convection and shear effect of the material in the drying cavity, significantly prolonging the residence time of the material. In this way, the material can be more fully contacted with hot air, and the uniformity of drying is improved in all directions. Moreover, this structure effectively reduces the impact force suffered by the particles during mechanical stirring, greatly reduces the possibility of particle damage, and ensures the quality of the chemical fertilizer raw material.
[0034] In terms of sealing and maintenance convenience, the design of the sealing end cover assembly is ingenious. It uses dovetail groove guide rail plug-in structure, matched with trapezoidal elastic sealing ring. During the operation of the equipment, the trapezoidal elastic sealing ring can produce radial expansion deformation under the action of axial compression force, and then form a reliable dynamic interference seal with the inner wall of the cylinder. This sealing method can perfectly adapt to the thermal expansion and contraction conditions caused by temperature changes, ensuring the sealing of the drying process. More importantly, the detachable design of the sealing end cover assembly is unique, greatly facilitating the cleaning and maintenance of the equipment, effectively reducing the maintenance cost of the equipment, improving the service life and operating efficiency of the equipment. BRIEF DESCRIPTION OF DRAWINGS
[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.
[0036] Figure 1 The structure diagram of the chemical fertilizer raw material drying device of an embodiment of the present application.
[0037] Figure 2 The structure diagram of the sealing end cover assembly of an embodiment of the present application.
[0038] Label explanation: cylinder (1), drying chamber (11), hemispherical protrusion (12), reverse helical guide vane (13), arc transition part (131), auxiliary stirring tooth (132), heating assembly (2), electric heating pipe (21), heat preservation layer (22), stirring assembly (3), main stirring shaft (31), forward helical blade (32), sealing end cover assembly (4), bottom cover (41), annular groove (411), pressure sensing assembly (412), elastic contact (412a), signal processing circuit board (412b), dovetail groove guide rail (42), sealing inner ring (43), flange (431), arc guide groove (431a), elastic sealing ring (44). DETAILED DESCRIPTION
[0039] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some but not all of the embodiments of the present application. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.
[0040] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor are within the scope of protection of the present application.
[0041] It should be noted that: similar labels and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. In the description of the embodiments of the present application, it is understood that the terms "upper", "lower", "left", "right", "vertical", "horizontal" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly placed when the product of the application is used, or the orientation or positional relationship commonly understood by those skilled in the art, and are only for the convenience of describing the present application and simplifying the description, and are not intended to indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.
[0042] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.
[0043] The technical solutions in the present application will be described below with reference to the drawings.
[0044] The embodiment provides a kind of chemical fertilizer raw material drying device, including cylinder 1, heating assembly 2, stirring assembly 3 and sealing end cap assembly 4, the inside of cylinder 1 is formed with the drying chamber 11 that passes through axially, and the two ends of drying chamber 11 are equipped with feed inlet and discharge outlet respectively;Heating assembly 2 is arranged around the outer wall of cylinder 1, and heating assembly 2 includes electric heating tube 21 distributed along the circumference of cylinder 1 and heat preservation layer 22 covered in the outer layer of electric heating tube 21;Stirring assembly 3 is coaxially arranged in drying chamber 11, including main stirring shaft 31, positive helical blade 32 fixed to the surface of main stirring shaft 31, and the inner wall of cylinder 1 is equipped with reverse helical guide plate 13 opposite in rotation direction with positive helical blade 32, and the installation position of reverse helical guide plate 13 and the helical trajectory of positive helical blade 32 form staggered distribution as shown in the figure Figure 1 Sealing end cap assembly 4 includes bearing and end cap structure that can be detachably connected to the two ends of cylinder 1, and the end cap structure includes bottom cover 41 connected with cylinder 1 in screw thread from outside to inside, sealing inner ring 43 inserted into the inner side of bottom cover 41 through dovetail slot guide rail 42, the side of sealing inner ring 43 towards the inside of cylinder 1 is equipped with elastic sealing ring 44 with trapezoidal section, and elastic sealing ring 44 generates radial expansion deformation under the action of axial compression force, and forms interference seal with the inner wall of cylinder 1. The interference amount of elastic sealing ring 44 is 0.5-1.2mm, and the material is high-temperature-resistant silicone rubber.
[0045] The chemical fertilizer raw material drying device has excellent performance, and can achieve multiple goals such as efficient drying, optimized heat distribution, enhanced mixing and fluidity, improved sealing and convenient maintenance.
[0046] In terms of efficient drying and optimized heat distribution, the cylinder is designed to pass through axially, and the electric heating tube is uniformly arranged on the outer wall in the circumferential direction. At the same time, the heat preservation layer tightly covers the electric heating tube, greatly reducing heat loss. The series of ingenious designs work together to enable uniform heat conduction in the drying cavity, effectively avoiding local overheating, thereby eliminating the problem of carbonization of fertilizer particles due to overheating, and ensuring efficient and stable drying process.
[0047] In terms of mixing and fluidity enhancement, the device innovatively adopts a unique structure of staggered distribution of positive helical blades and reverse helical guide plates. This careful design promotes the formation of strong convection and shear effect in the drying cavity, significantly prolonging the residence time of the material. In this way, the material can be more fully contacted with hot air, and the uniformity of drying is improved in all directions. Moreover, the structure effectively reduces the impact force suffered by the particles during mechanical stirring, greatly reducing the possibility of particle breakage and ensuring the quality of the chemical fertilizer raw material.
[0048] The design of the sealing end cover assembly is ingenious in terms of sealing performance and maintenance convenience. It uses dovetail slot guide rail insertion structure combined with trapezoidal elastic sealing ring. During the operation of the equipment, the trapezoidal elastic sealing ring can produce radial expansion deformation under the action of axial compression force, thereby forming a reliable dynamic interference seal with the inner wall of the cylinder. This sealing method can perfectly adapt to the thermal expansion and contraction conditions caused by temperature changes, ensuring the sealing performance during the drying process. More importantly, the detachable design of the sealing end cover assembly is unique and greatly facilitates the cleaning and maintenance of the equipment interior, effectively reducing the maintenance cost of the equipment and improving the service life and operating efficiency of the equipment.
[0049] The bearings, which can be purchased on the market, are used to connect the main stirring shaft and the cylinder and provide support.
[0050] In this embodiment, the material-approaching side edge of the reverse helical guide vane 13 is provided with auxiliary stirring teeth 132 extending towards the center of the drying chamber 11, and the extension direction of the auxiliary stirring teeth 132 forms an acute angle with the helical direction of the reverse helical guide vane 13.
[0051] The auxiliary stirring teeth 132 extend towards the center of the drying chamber, which can break the adhesion layer of the material on the surface of the guide vane and strengthen the rolling of the particles; the acute angle design forms local turbulence, which accelerates the escape of moisture, and is especially suitable for high-humidity raw material pretreatment. The extension direction of the stirring teeth 132 is complementary to the helical direction of the guide vane 13, which reduces the accumulation of material at the edge of the guide vane and reduces the frequency of shutdown cleaning.
[0052] In this embodiment, the top surface of the auxiliary stirring teeth 132 is a wedge-shaped structure, and the wedge-shaped tip thereof faces the rotation direction of the cylinder 1. The inclined surface of the wedge-shaped structure forms a parallel gap with the pushing surface of the forward helical blade 32.
[0053] The wedge-shaped tip faces the rotation direction, which reduces the resistance of the material passing through, and at the same time, the parallel gap between the inclined surface and the helical blade 32 forms a continuous shear band, which improves the crushing efficiency and avoids excessive extrusion of the particles. The wedge-shaped structure guides the airflow to rise along the inclined surface, enhances the convection of hot air in the drying chamber, and shortens the drying period.
[0054] In this embodiment, the helical pitch angle of the reverse helical guide vane 13 is smaller than that of the forward helical blade 32.
[0055] The smaller reverse helical pitch angle increases the resistance of the guide vane to the material, prolongs the residence time of the material in the high-temperature zone, and is suitable for deep dehydration of high-moisture raw materials. The large pitch angle of the forward helical blade 32 ensures the axial propulsion efficiency, and the small pitch angle of the reverse guide vane 13 forms a dynamic resistance balance, reducing the motor load fluctuation.
[0056] In the embodiment, the surface of the plate body of the reverse spiral baffle 13 is provided with an arc-shaped transition part 131 connected with the inner wall of the cylinder 1, and the inner wall of the cylinder 1 is provided with a hemispherical protrusion 12, the curvature of the arc-shaped transition part 131 matches the spherical curvature of the hemispherical protrusion 12.
[0057] The arc-shaped transition part 131 reduces the residence of materials at the connection between the baffle and the cylinder, preventing uneven drying caused by local material accumulation; the staggered distribution of the hemispherical protrusions 12 forms a mechanical support with the transition part of the baffle, reducing the risk of deformation of the baffle due to thermal stress.
[0058] In the embodiment, the inner side end surface of the bottom cover 41 is provided with an annular groove 411, the outer periphery of the sealing inner ring 43 is provided with a flange 431 matched with the annular groove 411, and a pressure sensing assembly 412 is arranged between the bottom surface of the flange 431 and the annular groove 411, the pressure sensing assembly 412 includes a plurality of elastic contacts 412a in contact with the bottom surface of the flange 431, a signal processing circuit board 412b embedded in the bottom cover, and a signal output interface connected with the circuit board.
[0059] The elastic contacts 412a feedback the compression amount of the sealing inner ring 43, the signal processing circuit board 412b can early warn the sealing failure, preventing heat loss or dust leakage caused by loose sealing during the drying process. The matching design of the annular groove 411 and the flange 431 allows the sealing inner ring 43 to be adjusted in position under thermal expansion, ensuring that the elastic sealing ring 44 is in continuous and effective contact.
[0060] In the embodiment, the top of the elastic contact 412a is a spherical cap contact surface, the bottom surface of the flange 431 is provided with an arc-shaped guide groove 431a complementary to the shape of the spherical cap contact surface, and the compression stroke direction of the elastic contact 412a is consistent with the axial movement direction of the sealing inner ring 43.
[0061] The spherical cap contact surface and the guide groove 431a are complementary in shape, reducing the eccentric wear of the contact when moving axially, prolonging the service life of the sensor; the compression stroke direction is consistent with the movement direction of the sealing inner ring 43, ensuring that the pressure signal truly reflects the sealing state and avoiding false alarms.
[0062] In the embodiment, the hemispherical protrusions 12 are arranged in a staggered manner on the inner wall of the cylinder 1, forming at least two rows of axially extending protrusion arrays, and the projection positions of each row of protrusion arrays correspond to the spiral gap regions of the reverse spiral baffle 13.
[0063] The staggered protrusion arrays form secondary vortexes in the gap regions of the baffle, enhancing the contact area of the materials and hot air and improving the thermal efficiency; the spherical structure of the protrusions reduces material adhesion, and cooperates with the stirring assembly 3 to realize self-cleaning of the inner wall of the cylinder.
[0064] In the embodiment, the plurality of elastic contacts 412a are uniformly distributed along the circumference of the annular groove 411.
[0065] The uniform distribution contact can monitor the compression force of the sealing inner ring 43 in all directions, and avoid deformation failure of the sealing ring caused by local overload; the multi-point monitoring improves the reliability of the system, and the sealing state can still be maintained by the remaining contacts when a single contact fails.
[0066] Although the embodiments of the present application have been shown and described, it should be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.
Claims
1. A fertilizer raw material drying device, characterized in that, The utility model relates to a kind of drying machine, including Cylinder (1), the inside of the cylinder (1) forms the axial through drying chamber (11), the both ends of the drying chamber (11) are equipped with inlet and outlet respectively; Heating assembly (2), it is set around the outer wall of the cylinder (1), and the heating assembly (2) includes electric heating tube (21) and heat preservation layer (22) of the outer layer of electric heating tube being distributed along the circumferential direction of cylinder including; Stirring assembly (3), coaxially set in the drying chamber (11), including main stirring shaft (31), positive helical blade (32) fixed to the surface of main stirring shaft, the inner wall of the cylinder is equipped with reverse helical guide plate (13) with the opposite rotation direction of positive helical blade, and the installation position of the reverse helical guide plate (13) forms staggered distribution with the helical trajectory of positive helical blade (32), forms convection shear effect to reduce particle breakage; Sealing end cover assembly (4), including bearing and end cover structure being detachably connected to the both ends of cylinder, the end cover structure includes bottom cover (41) from outside to inside in proper order, sealing inner ring (43) is inserted in the inner side of bottom cover by dovetail slot guide rail (42), the side of sealing inner ring (43) towards the inside of cylinder is equipped with trapezoidal section elastic sealing ring (44), the radial expansion deformation of elastic sealing ring (44) is generated under the action of axial compression force, and forms interference seal with the inner wall of cylinder.
2. The chemical fertilizer raw material drying device according to claim 1, characterized in that, The material-receiving side edge of the reverse helical guide plate (13) is provided with an auxiliary stirring tooth (132) extending towards the center of the drying chamber, and the extension direction of the auxiliary stirring tooth (132) forms an acute angle with the spiral direction of the reverse helical guide plate (13).
3. The chemical fertilizer raw material drying device according to claim 2, characterized in that, The top surface of the auxiliary stirring tooth (132) is a wedge-shaped structure, the wedge-shaped tip of which faces the rotation direction of the cylinder, and the inclined surface of the wedge-shaped structure forms a parallel gap with the advancing surface of the positive helical blade (32).
4. The chemical fertilizer raw material drying device according to claim 1, characterized in that, The helical pitch angle of the reverse helical guide plate (13) is smaller than that of the positive helical blade (32).
5. The chemical fertilizer raw material drying device according to claim 1, characterized in that, The surface of the plate body of the reverse helical guide plate (13) is provided with an arc-shaped transition portion (131) connected with the inner wall of the cylinder, the inner wall of the cylinder is provided with a hemispherical protrusion (12), and the curvature of the arc-shaped transition portion (131) matches the spherical curvature of the hemispherical protrusion (12).
6. The chemical fertilizer raw material drying device according to claim 1, characterized in that, The inner side end surface of the bottom cover (41) is provided with an annular groove (411), the outer periphery of the sealing inner ring (43) is provided with a flange (431) matched with the annular groove, a pressure sensing assembly (412) is arranged between the bottom surface of the flange (431) and the annular groove (411), the pressure sensing assembly (412) includes a plurality of elastic contacts (412a) in contact with the bottom surface of the flange, a signal processing circuit board (412b) embedded in the bottom cover, and a signal output interface connected with the circuit board.
7. The chemical fertilizer raw material drying device according to claim 6, characterized in that, The top part of the elastic contact (412a) is a spherical cap-shaped contact surface, the bottom surface of the flange (431) is provided with an arc-shaped guide groove (431a) complementary to the shape of the spherical cap-shaped contact surface, and the compression stroke direction of the elastic contact (412a) is consistent with the axial movement direction of the sealing inner ring (43).
8. The chemical fertilizer raw material drying device according to claim 5, characterized in that, The hemispherical protrusions (12) are staggered on the inner wall of the cylinder to form at least two rows of axially extending protrusion arrays, and the projection positions of each row of protrusion arrays correspond to the helical gap regions of the reverse helical guide vanes (13).
9. The chemical fertilizer raw material drying device according to claim 6, characterized in that, The plurality of elastic contacts (412a) are evenly distributed along the circumferential direction of the annular groove.