Vacuum spiral dryer

Abstract

The utility model discloses a vacuum spiral dryer which comprises a plurality of spiral conveyors which are vertically arranged and sequentially communicated end to end, the spiral conveyors are connected with an upper material storage hopper and a lower material storage hopper, and the upper material storage hopper and the lower material storage hopper are respectively provided with a valve. The spiral conveyor comprises a conveying barrel, a hollow spiral conveyor U-shaped groove and a spiral conveying shaft, the spiral conveying shaft penetrates through the two ends of the conveying barrel, one end of the spiral conveying shaft is connected with a rotary connector, the other end of the spiral conveying shaft is connected with a conveying shaft speed reducer, and the spiral conveyor U-shaped groove supports and makes contact with the outer surface of the conveying barrel. A U-shaped groove heat source medium inlet and a U-shaped groove heat source medium outlet are respectively formed in the spiral conveyor U-shaped groove, a material conveying shaft heat source medium inlet and a material conveying shaft heat source medium outlet are respectively formed in the rotary joint, and the spiral conveyor is communicated with a vacuum system. The device performs internal and external matched heating on materials, is high in heat conversion benefit, reduces the vaporization boiling point of water, works in a totally closed environment, and does not generate dust.

Description

Technical Field

[0001] The utility model relates to the field of material drying and processing, in particular to a vacuum spiral drying machine. Background Art

[0002] Material dryers can indirectly heat or cool paste, granular, powdery, and slurry materials, and can complete unit operations such as drying, cooling, heating, sterilization, reaction, and low-temperature calcination. They have high heat transfer efficiency. At present, this type of dryer has been successfully used in food, chemical, petrochemical, dye, industrial sludge and other fields. At present, the types of material dryers include paddle dryers, rotary dryers, and belt dryers. However, there are some problems with the above types of material dryers: 1. Paddle dryers are generally non-vacuum when working, and cannot effectively reduce the boiling point of water, and the drying time is long; 2. For sticky materials such as sludge, rotary dryers are generally not suitable, and dust is flying when rotating, which causes great air pollution; 3. Belt dryers can only place the dried materials (such as food, agricultural products, aquatic products, etc.) on the conveyor belt in a static state for drying, so the drying efficiency is not high, and it can generally only be adapted to some materials that are not allowed to break. Utility Model Content

[0003] In view of the problems existing in the material drying equipment in the above-mentioned prior art, the utility model provides a vacuum spiral dryer which can reduce the evaporation boiling point of material water, improve the heating and drying efficiency, and reduce dust pollution in the working environment.

[0004] The technical solution adopted by the utility model to solve the technical problem is: a vacuum spiral dryer, which includes a plurality of spiral conveyors arranged vertically on a frame and connected end to end in sequence, the uppermost spiral conveyor is connected to an upper material storage hopper, and the lowermost spiral conveyor is connected to a lower material storage hopper, and an upper storage hopper valve and a lower storage hopper valve are respectively provided on the upper material storage hopper and the lower material storage hopper, the spiral conveyor includes a feeding barrel, a hollow U-shaped groove of the spiral conveyor and a spiral feeding shaft, the spiral feeding shaft passes through both ends of the feeding barrel, one end of the spiral feeding shaft is connected to a rotary joint, and the other end is connected to a feeding shaft reducer, the U-shaped groove of the spiral conveyor supports and closely contacts the outer surface of the feeding barrel, the U-shaped groove of the spiral conveyor is respectively provided with a U-shaped groove heat source medium inlet and a U-shaped groove heat source medium outlet, the rotary joint is respectively provided with a feeding shaft heat source medium inlet and a feeding shaft heat source medium outlet, and the spiral conveyor is connected to a vacuum system.

[0005] Furthermore, a heat-resistant sealing ring of the spiral feed shaft is provided on the end surface of the spiral feed shaft.

[0006] Furthermore, the vacuum system also includes a dust filter 7 .

[0007] The utility model has the following beneficial effects:

[0008] 1. Compared with traditional dryers (paddle dryers, turntable dryers, belt dryers), the U-shaped groove of the screw conveyor of the vacuum spiral dryer is heated by heat source medium, and the spiral feed shaft is also heated by heat source medium. The heat source medium heats the material inside and outside, and the heat conversion efficiency is high.

[0009] 2. The material is dried in a fully enclosed manner. The material is fully in contact with the spiral U-shaped groove and the spiral feed shaft for heating. The material is dried in a vacuum state, which reduces the vaporization boiling point of water and accelerates the evaporation of water in the material.

[0010] 3. Work in a fully enclosed environment without generating dust. Use a vacuum machine to extract water vapor, and then discharge the condensed water after condensation.

[0011] 4. The continuous working mode is adopted. When the material is stored in the upper storage hopper, the upper material valve is closed, and the screw conveyor conveys the material while heating it and conveys it to the material outlet, and then stores it in the lower material storage hopper. When the lower material hopper stores a certain amount, the lower material storage hopper is opened to release the dried material, and then the material is mechanically transported out through the discharging conveyor belt. When the material in the upper storage hopper is reduced by a certain amount, the valve is opened, and the upper material conveyor conveys the material to the upper storage hopper. When the material reaches a certain amount, the valve is closed to ensure that the material is always dried under vacuum.

[0012] 5. The three-stage spiral type works continuously, but the upper / lower material storage hopper works intermittently through the valve control switch. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of the main cross-sectional structure of the utility model;

[0014] Figure 2 This is a schematic diagram of the structure of the utility model in the feeding working state;

[0015] Figure 3 This is a schematic diagram of the structure of the utility model in the drying working state;

[0016] Figure 4 It is a structural schematic diagram of the utility model in a state of preparing for unloading.

[0017] In the figure, 1. upper material storage hopper; 2. upper storage hopper valve; 3. U-shaped groove of screw conveyor; 4. feeding barrel; 5. screw feeding shaft; 6. vacuum system; 7. dust filter; 8. heat-resistant sealing ring of feeding shaft; 9. feed shaft reducer; 10. lower material storage hopper; 11. discharging conveyor; 12. lower storage hopper valve; 13. heat source medium outlet of feeding shaft; 14. heat source medium inlet of feeding shaft; 15. rotary joint; 16. connecting heat-resistant sealing pad; 17. heat source medium inlet of U-shaped groove; 18. heat source medium outlet of U-shaped groove; 19. heat source medium; 20. rack. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings.

[0019] As shown in the figure, the vacuum spiral dryer comprises a plurality of spiral conveyors arranged vertically and connected end to end in sequence on a frame 20 (heat-resistant sealing rubber pads 16 are provided at the connection points between each other), the top spiral conveyor is connected to the upper material storage hopper 1, the bottom spiral conveyor is connected to the lower material storage hopper 10, the upper material storage hopper and the lower material storage hopper are respectively provided with an upper storage hopper valve 2 and a lower storage hopper valve 12, the spiral conveyor comprises a feeding cylinder 4, a hollow spiral conveyor U-shaped groove 3 and a spiral feed shaft 5, the spiral feed shaft passes through both ends of the feed barrel, one end of the spiral feed shaft is connected to a rotary joint 15, and the other end is connected to a feed shaft reducer 9, the U-shaped groove of the screw conveyor supports and closely contacts the outer surface of the feed barrel, the U-shaped groove of the screw conveyor is respectively provided with a U-shaped groove heat source medium inlet 17 and a U-shaped groove heat source medium outlet 18, the rotary joint is respectively provided with a feed shaft heat source medium inlet 14 and a feed shaft heat source medium outlet 13, and the screw conveyor is connected to a vacuum system 6.

[0020] In order to better ensure the sealing performance of the equipment, a heat-resistant sealing ring 8 of the spiral feed shaft is provided on the end surface of the spiral feed shaft.

[0021] In order to better solve the dust pollution problem when the equipment is working, the vacuum system also includes a dust filter 7.

[0022] In addition, if Figure 1 As shown, a specific connection structure of multiple screw conveyors is as follows: the first section feed port of the vacuum screw dryer is connected to the upper material storage hopper, the first section discharge port is connected to the feed port of the second section of the vacuum screw dryer, the second section vacuum screw dryer outlet is connected to the feed port of the third section of the vacuum screw dryer, and the third section vacuum screw dryer discharge port is connected to the lower material storage hopper.

[0023] In addition, the vacuum spiral dryer also includes but is not limited to the following ancillary equipment: a material feeder (for conveying materials to the upper storage hopper), a hot water boiler / air energy water heater / electromagnetic heater, etc. to provide a drying heat source, an automatic control electric control cabinet, a heating heat source medium control ball valve, a vacuum control ball valve, etc., and a discharge conveyor belt 11.

[0024] In addition, the drying method of the vacuum spiral dryer comprises the following steps:

[0025] S1: Open the upper storage hopper valve, the material feeder starts to load materials, and the materials gradually fall from the upper storage hopper to the screw conveyor. After the materials in the upper storage hopper fall a set amount, the upper storage hopper valve is closed;

[0026] S2: Start the vacuum system to extract the air in the screw conveyor to make it a vacuum state. The screw conveyor conveys the undried material while introducing the heat source medium 19 (such as hot steam, hot water, heat transfer oil, etc.) into the heat source medium inlet on the screw conveyor U-shaped groove outside the feeding barrel and the screw feeding shaft inside the feeding barrel. The external and internal heat source media heat and dry the material between them in a non-contact manner until it is transported to the material outlet;

[0027] S3: storing the dried material in the material lower storage hopper. After the storage in the lower material hopper reaches the set amount, opening the lower storage hopper valve of the material lower storage hopper, releasing the dried material, and sending it out through the discharge conveyor 11;

[0028] S4: After the material in the material upper storage hopper is reduced to the set amount, the upper storage hopper valve of the material upper storage hopper is opened. After the material feeder conveys the material to the material upper storage hopper to reach the set amount, the upper storage hopper valve of the material upper storage hopper is closed to ensure that the material is always dried under a vacuum state. The material drying is completed in a cycle according to the above steps.

[0029] In the above, the automatic control parts such as PLC controller, vacuum system on / off, electromagnetic valve on / off, etc. that are not described in detail belong to the prior art. The above implementation mode is only used to illustrate the technical solution of the utility model but not to limit it. Although the utility model is described in detail with reference to specific embodiments, ordinary technicians in this field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the utility model, which should be included in the scope of protection of the claims of the utility model.

Claims

1. Vacuum spiral dryer, characterized by: The invention comprises a plurality of screw conveyors arranged vertically and connected end to end in sequence on a frame (20), wherein the uppermost screw conveyor is connected to an upper material storage hopper (1), and the lowermost screw conveyor is connected to a lower material storage hopper (10), and the upper material storage hopper and the lower material storage hopper are respectively provided with an upper storage hopper valve (2) and a lower storage hopper valve (12), and the screw conveyor comprises a feeding barrel (4), a hollow screw conveyor U-shaped groove (3) and a screw feeding shaft (5), wherein the screw feeding shaft is provided with a Passing through both ends of the feed barrel, one end of the spiral feed shaft is connected to a rotary joint (15), and the other end is connected to a feed shaft reducer (9). The U-shaped groove of the spiral conveyor supports and is in close contact with the outer surface of the feed barrel. The U-shaped groove of the spiral conveyor is respectively provided with a U-shaped groove heat source medium inlet (17) and a U-shaped groove heat source medium outlet (18). The rotary joint is respectively provided with a feed shaft heat source medium inlet (14) and a feed shaft heat source medium outlet (13). The spiral conveyor is connected to a vacuum system (6).

2. The vacuum spiral dryer according to claim 1, characterized in that: The end surface of the spiral feed shaft is provided with a feed shaft heat-resistant sealing ring (8).

3. The vacuum spiral dryer according to claim 1, characterized in that: The vacuum system also includes a dust filter (7).

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