Rotary powder drying device

Abstract

The utility model discloses a rotary powder drying device which is characterized in that a box body is divided into a heating cavity and a drying cavity through a horizontal partition plate, a wavy heating pipe and an axial flow fan are arranged in the heating cavity, an airflow leading-in block and an airflow leading-out block which are provided with flow guide pipe matrixes are arranged on the two sides of the drying cavity respectively, and conical diffusion openings are formed in the outlet ends of the flow guide pipes. The hole diameters of screening holes of all the layers of material discs are gradually decreased from top to bottom, and vortex airflow is formed in cooperation with the spiral flow guide grooves. According to the device, a ceramic heat insulation layer, a polytetrafluoroethylene coating and a variable-frequency and variable-speed motor are linked with a temperature and humidity sensor, and efficient anti-caking drying of hygroscopic powder is achieved. By means of the innovative structure, the heat efficiency is improved by more than 40%, the unit energy consumption is reduced to 1.2-1.5 kWh / kg, the drying uniformity deviation is smaller than + / -5% RH, and the device is suitable for the high-requirement field such as industrial degreased powder production.

Description

Technical Field

[0001] This utility model relates to the field of powder drying technology, and in particular to a rotary powder drying device. Background Technology

[0002] Industrial degreasing powder production uses hygroscopic powder raw materials such as sodium silicate. These raw materials need to be dried using powder drying equipment before synthesis. Traditional drying technologies face the following problems:

[0003] 1. After absorbing moisture, the surface tension of the powder increases, and static drying easily leads to the formation of hard lumps, resulting in a 50%-70% decrease in heat transfer efficiency. 2. Conventional fluidized bed drying requires maintaining high temperatures (>120℃) to overcome the effects of humidity, with energy consumption as high as 2.5-3.2 kWh / kg. 3. Hygroscopic powders are prone to localized over-wetting during dynamic drying (humidity deviation >15%RH), increasing the risk of microbial growth. Utility Model Content

[0004] The technical problem to be solved by this utility model is to overcome the defects of the prior art and provide a rotary powder drying device.

[0005] To solve the above-mentioned technical problems, this utility model provides the following technical solution:

[0006] This utility model discloses a rotary powder drying device, comprising a housing, the interior of which is divided into an upper heating chamber and a lower drying chamber by a horizontal partition. The heating chamber contains a corrugated heating tube. An axial flow fan is mounted on the top of the housing, and the outlet of the axial flow fan is connected to the top of the heating chamber. An airflow inlet block is embedded in the right side wall of the drying chamber, and an airflow outlet block is embedded in the left side wall. The airflow inlet block supplies air to the drying chamber through a matrix of guide pipes arranged equidistantly in a vertical direction. The outlet end of each guide pipe has a conical diffuser. The airflow outlet block has an airflow guide opening and a gas outlet. A turntable shaft vertically penetrates the drying chamber, and its top end is connected to a drive motor via a coupling. 3-8 layers of inclined material trays are fixedly mounted on the turntable shaft. Screening holes are evenly distributed on the surface of each material tray, with the hole diameter decreasing by 0.2-0.5 mm from the upper material tray to the lower tray. A funnel-shaped material inlet is located at the top of the housing, and a funnel-shaped material outlet is located at the bottom. A temperature and humidity sensor is embedded in the outer wall of the housing.

[0007] As a preferred technical solution of this utility model, the wave crest curvature radius R of the corrugated heating tube is 3-8mm, the wave pitch L is 20-40mm, and the spacing between adjacent heating tubes is 5-15mm; the inner wall of the heating cavity is provided with a ceramic heat insulation layer.

[0008] As a preferred technical solution of this utility model, the inner diameter of the guide tube is 8-20mm, the tube wall is provided with a spiral guide groove, and the axial angle between the guide tube and the horizontal plane is 0-10°.

[0009] As a preferred embodiment of this utility model, the material tray is tilted at an angle of 15-25°, and the vertical distance between adjacent material trays is 1.2-1.5 times the diameter of the material tray.

[0010] As a preferred embodiment of this utility model, the drive motor is a flange-mounted variable frequency speed control motor.

[0011] As a preferred embodiment of this utility model, the surface of the material tray is coated with a polytetrafluoroethylene coating with a thickness of 50-200μm, and the edges of the screening holes are chamfered.

[0012] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0013] 1. The multi-layer inclined material tray, combined with the screening hole design with decreasing aperture, enables simultaneous step-by-step drying of powder and particle size sorting. When hygroscopic powder passes through the gradually narrowing aperture layer by layer from top to bottom, the residence time of each layer is shortened to 30-60 seconds, the surface moisture evaporation rate is increased by 40%, and the agglomeration rate is reduced to <3% (15%-20% in traditional processes);

[0014] 2. The corrugated heating tube, through optimized crest curvature and wave pitch design, increases the heat exchange area by 45% compared to the straight tube. Combined with the high heat reflectivity (>85%) of the ceramic insulation layer, it can still maintain a thermal efficiency of 68%-72% in a high humidity environment of 90%RH. The spiral guide groove of the guide tube and the conical diffuser form a vortex airflow, which controls the humidity gradient of the drying chamber within ±5%RH, avoiding local over-humidity.

[0015] 3. The humidity at the outlet of the drying chamber is monitored in real time by a temperature and humidity sensor, and the speed of the turntable is adjusted by a variable frequency speed control motor (50-300 rpm) to ensure that the final moisture content is ≤0.5%. Attached Figure Description

[0016] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0018] Figure 2 This is the front view of this utility model;

[0019] Figure 3 This is a side view of the present invention;

[0020] Figure 4 This is a schematic cross-sectional view of the present invention;

[0021] Figure 5 This is a cross-sectional structural schematic diagram (b) of this utility model;

[0022] In the diagram: 1. Housing; 2. Axial flow fan; 3. Airflow inlet block; 4. Airflow outlet block; 5. Turntable shaft; 6. Coupling; 7. Drive motor; 8. Material inlet; 9. Material outlet; 10. Temperature and humidity sensor; 11. Heating chamber; 12. Drying chamber; 13. Heating tube; 14. Horizontal partition; 31. Guide pipe; 32. Diffuser; 41. Airflow guide opening; 42. Gas outlet; 51. Material tray; 52. Screening hole. Detailed Implementation

[0023] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0024] In the attached diagram, all identical reference numerals refer to the same components.

[0025] The following is Example 1 of this utility model patent:

[0026] like Figure 1-5 As shown, this utility model provides a rotary powder drying device. The box body 1 is made of 304 stainless steel with a thickness of 3mm. The interior is divided into a heating chamber 11 and a drying chamber 12 by a horizontal partition 14 with a thickness of 4mm welded on. The heating chamber 11 has a height of 300mm, the drying chamber 12 has a height of 800mm, the total height of the box body is 1500mm, and the diameter is 800mm.

[0027] Six corrugated heating tubes 13 are installed inside the heating chamber 11. Each tube is 2m long, with a crest curvature radius R of 5mm and a wave pitch L of 30mm. The spacing between adjacent heating tubes is 20mm, and they are arranged in a staggered pattern at 45°. The outer surface of the heating tubes is provided with spiral fins with a height of 2mm and a pitch of 8mm. The inner wall of the heating chamber 11 is coated with a 1.5mm thick alumina ceramic insulation layer.

[0028] The axial flow fan 2 is fixed to the top of the housing 1 via a flange, and has a power of 1.5kW.

[0029] The right side wall of the drying chamber 12 is fitted with an air flow inlet block 3, which has 4 rows of vertical guide tubes 31, 6 tubes in each row. The inner diameter of the guide tube is 12mm, and the tube wall has a spiral guide groove with a pitch of 10mm and a depth of 1.2mm. The axial angle between the guide tube and the horizontal plane is 5°, and the outlet end is provided with a conical diffuser 32 with a diffusion angle of 25°.

[0030] Please see the appendix Figure 4 The turntable shaft 5 is connected to the flange-mounted variable frequency speed control motor 7 via a coupling (6), with an output torque of 120 N·m. Five layers of material trays 51 inclined at 20° are installed on the turntable shaft 5. The material is 316L stainless steel, the tray diameter is 600 mm, and the distance between adjacent trays is 720 mm. The diameters of the screening holes 52 of each layer of material trays are 0.8 mm, 0.6 mm, 0.4 mm, 0.3 mm, and 0.2 mm from top to bottom, with a hole density of 60 holes / cm², and they are radially distributed. The edge of the screening hole has a chamfer of R0.15 mm.

[0031] Please see the appendix Figure 5 The top of the box 1 is provided with a funnel-shaped material inlet 8 and the bottom is provided with a material outlet 9 with a cone angle of 60°. A temperature and humidity sensor 10 is embedded on the outer wall 120mm above the uppermost material tray 51, and the probe extends to 20mm below the uppermost material tray 51.

[0032] The following is Embodiment 2 of this utility model patent: an optimized implementation for high humidity environments.

[0033] The corrugated heating tube 13 has a peak curvature radius R of 8mm, a wave pitch L of 40mm, an outer surface spiral fin height of 3mm, and an inner wall ceramic insulation layer thickness of 2.5mm.

[0034] The inner diameter of the guide tube 31 is increased to 18mm, the depth of the spiral guide groove is increased to 1.5mm, and the diffusion angle of the diffuser 32 is increased to 30°, forming stronger turbulence to cope with humidity >85%RH conditions.

[0035] The surface of the material tray 51 is coated with a polytetrafluoroethylene composite coating containing 20% ​​nano-alumina. The coating thickness is 150μm and the surface roughness Ra is 0.5μm. A 0.2mm nickel-based transition layer is set between the coating and the substrate.

[0036] The verification results for Examples 1 and 2 are as follows:

[0037]

[0038] The implementation effect of this embodiment is as follows:

[0039] The progressively decreasing aperture design of the 52 screening holes ensures continuous dispersion of powder during dynamic descent. Combined with the vortex airflow generated by the spiral guide groove, the agglomeration rate is reduced to below 2%.

[0040] The synergistic design of the corrugated heating tube 13 and the spiral fins increases the thermal efficiency to 70% and reduces the unit energy consumption by 53%.

[0041] The linkage between the diffuser 32 of the guide tube 31 and the temperature and humidity sensor 10 controls the humidity fluctuation of the drying chamber within ±5%RH.

[0042] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A rotary powder drying device, comprising a housing (1), characterized in that: The interior of the housing (1) is divided into an upper heating chamber (11) and a lower drying chamber (12) by a horizontal partition (14). The heating chamber (11) is equipped with a corrugated heating pipe (13). An axial flow fan (2) is installed on the top of the housing (1), and the air outlet of the axial flow fan (2) is connected to the top of the heating chamber (11). An air flow inlet block (3) is embedded in the right side wall of the drying chamber (12), and an air flow outlet block (4) is embedded in the left side wall. The air flow inlet block (3) supplies air to the drying chamber (12) through a matrix of guide pipes (31) arranged equidistantly in the vertical direction. The outlet end of the guide pipe (31) is provided with a conical diffuser (3). 2) The airflow outlet block (4) is provided with an airflow guide opening (41) and a gas outlet (42); the turntable shaft (5) penetrates the drying chamber (12) vertically, and its top end is connected to the drive motor (7) through a coupling (6). 3-8 layers of inclined material trays (51) are fixedly installed on the turntable shaft (5); screening holes (52) are evenly distributed on the surface of each layer of material tray (51), and the diameter of the screening holes (52) decreases by 0.2-0.5 mm from the upper layer of material tray (51) to the lower layer; the top of the box is provided with a funnel-shaped material inlet (8), and the bottom is provided with a funnel-shaped material outlet (9); a temperature and humidity sensor (10) is embedded on the outer wall of the box.

2. The rotary powder drying device according to claim 1, characterized in that, The wave-shaped heating tube (13) has a wave crest curvature radius R of 3-8mm, a wave pitch L of 20-40mm, and a spacing of 5-15mm between adjacent heating tubes (13); the inner wall of the heating cavity (11) is provided with a ceramic heat insulation layer.

3. The rotary powder drying device according to claim 1, characterized in that, The inner diameter of the guide tube (31) is 8-20mm, and a spiral guide groove is opened on the tube wall. The axial angle between the guide tube (31) and the horizontal plane is 0-10°.

4. The rotary powder drying apparatus according to claim 1, characterized in that, The material tray (51) has an inclination angle of 15-25°, and the vertical distance between adjacent material trays (51) is 1.2-1.5 times the diameter of the material tray.

5. A rotary powder drying apparatus according to claim 1, characterized in that, The drive motor (7) is a flange-mounted variable frequency speed control motor.

6. A rotary powder drying apparatus according to claim 1, characterized in that, The material tray (51) is coated with a polytetrafluoroethylene coating with a thickness of 50-200 μm, and the edges of the screening holes (52) are chamfered.

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