Double-cone rotary vacuum dryer

Abstract

A double-cone rotary vacuum drying machine overcomes the defects that in the prior art, when a double-cone rotary vacuum drying machine is used for discharging, discharging work is tedious, powder overflows, dust pollution is caused and the like, and comprises a drying machine body, a vacuumizing system and a pneumatic conveying system. A material conveying pipeline of the pneumatic conveying system penetrates through a vacuum pipeline of the vacuumizing system and extends into the drying machine body. The gas balance system comprises a gas conveying pipeline, a gas supplementing device and a gas extracting device; one end of the gas conveying pipeline penetrates through a vacuum pipeline of the vacuumizing system and extends into the drying machine body; and the other end of the gas conveying pipeline is respectively connected with the gas supplementing device and the gas extracting device through valves. According to the superfine powder pneumatic conveying device, effective pneumatic conveying of superfine powder can be achieved without opening the discharging port, dust overflowing cannot be caused, and dust pollution is avoided.

Description

Technical Field

[0001] The utility model relates to the field of powder drying equipment, in particular to a double-cone rotary vacuum dryer. Background Art

[0002] The double-cone rotary vacuum dryer is a double-cone rotary tank body. Inside the tank, under vacuum conditions, steam or hot water is introduced into the jacket for heating. The heat contacts the wet material through the inner wall of the tank. The water vapor evaporated by the wet material after absorbing heat is pumped away through a vacuum exhaust pipe by a vacuum pump. Since the inside of the tank is in a vacuum state and the rotation of the tank body causes the material to continuously turn up and down, inside and outside, the drying speed of the material is accelerated, the drying efficiency is improved, and the purpose of uniform drying is achieved.

[0003] Chinese Patent with publication number CN 217715731 U discloses a double-cone rotary dryer for drying salicylamide, which improves the feeding part of the traditional double-cone rotary vacuum dryer and solves the problem of cumbersome feeding.

[0004] And the patent document discloses that a pneumatic conveyor is adopted in the discharging part to realize the pneumatic conveying of discharging. However, the following problems still exist in its application process: it is necessary to stop the machine during discharging, then open the discharging butterfly valve, and then convey the material through the pneumatic conveyor. The discharging work is still cumbersome; and when opening the discharging butterfly valve, the overflow of ultra-fine powder cannot be avoided, resulting in dust pollution and being unfavorable to the health of the staff. Summary of the Utility Model

[0005] The utility model overcomes the disadvantages that the discharging work of the double-cone rotary vacuum dryer in the prior art is cumbersome and there is powder overflow, resulting in dust pollution, etc., and provides a double-cone rotary vacuum dryer.

[0006] To achieve the above invention purposes, the technical solution adopted by the utility model is: a double-cone rotary vacuum dryer, comprising: a dryer body, a vacuum pumping system and a pneumatic conveying system. The vacuum pipeline of the vacuum pumping system extends into the dryer body, and a vacuum filter head for filtering the powder in the dryer body during vacuum pumping is provided at the extended end of the vacuum pipeline; the material conveying pipeline of the pneumatic conveying system is connected to the dryer body.

[0007] The material conveying pipeline of the pneumatic conveying system penetrates through the vacuum pipeline of the vacuum pumping system and extends into the dryer body. The double-cone rotary vacuum dryer further comprises: a gas balance system; the gas balance system comprises: a gas conveying pipeline, a gas supplementing device and a gas pumping device; one end of the gas conveying pipeline penetrates through the vacuum pipeline of the vacuum pumping system and extends into the dryer body; the other end of the gas conveying pipeline is respectively connected to the gas supplementing device and the gas pumping device through valves.

[0008] The beneficial effects of the present utility model are as follows: (1) A gas balance system is provided and combined with the pneumatic conveying system to realize the conveying of materials in the sealed dryer body.

[0009] (2) The powder conveying pipeline of the pneumatic conveying system and the gas conveying pipeline of the gas balance system are extended into the dryer body of the double-cone rotary dryer. With this setting, when feeding and discharging materials in the double-cone rotary dryer, it is not necessary to open the tank mouth, and the feeding and discharging of ultrafine powder can be realized, thereby effectively avoiding powder overflow and effectively solving the problem of dust pollution.

[0010] (3) The powder pneumatic conveying pipeline and the gas conveying pipeline are arranged in the vacuum pipeline of the original double-cone rotary dryer in an embedded manner, without changing the structure of the dryer body of the original double-cone rotary dryer, ensuring the sealing performance of the dryer body. Description of the Drawings

[0011] Att Figure 1 is a schematic structural diagram of the present utility model.

[0012] Att Figure 2 is Figure 1 the sectional view taken along the line A-A of

[0013] Att Figure 3 is Figure 1 the partial enlarged view B of

[0014] Att Figure 4 is a schematic structural diagram of another embodiment of the present utility model.

[0015] In the drawings, 1 is the dryer body, 2 is the vacuum system, 2-1 is the vacuum pipeline, 2-1-1 is the vacuum filter head, 2-1-2 is the vacuum valve, 3 is the pneumatic conveying system, 3-1 is the material conveying pipeline, 3-1-1 is the aggregate cover, 3-1-2.1 is the hose, 3-1-2.2 is the gravity suction ball, 3-1-3 is the material valve, 4-1 is the gas conveying pipeline, 4-1-1 is the air extraction filter screen, 4-2 is the air supply device, 4-2-1 is the air supply valve, 4-3 is the air extraction device, and 4-3-1 is the air extraction valve.

[0016] The present invention will be further described below through specific embodiments. Specific Embodiments

[0017] In the double-cone rotary vacuum dryer of the present utility model, on the basis of the existing double-cone rotary dryer, the feeding and discharging of materials are improved to realize pneumatic conveying of materials and reduce dust pollution. The specific structure is described as follows:

[0018] A double-cone rotary vacuum dryer includes: a dryer body 1, a vacuum pumping system 2, and a pneumatic conveying system 3.

[0019] The dryer body 1 is the main body of the double-cone rotary vacuum dryer, which adopts a double-cone structure. Powders are placed in the inner cavity of the dryer body 1, and hot liquid or steam is passed through the jacket of the dryer body 1. After the inner cavity is evacuated, the dryer body 1 is controlled to turn up and down along its own horizontal axis so that the powders in the cavity are evenly heated and dried. Since the dryer body 1 needs to turn during operation, the dryer body 1 is generally installed on the frame 5. At the same time, in order to facilitate and flexibly handle the equipment, the frame 5 is generally set as a movable frame. Specifically, rollers that can move and stop can be provided at the bottom of the frame 5.

[0020] When the vacuum pumping system 2 is used to dry powders, it controls the vacuum degree inside the dryer body 1. The vacuum pipeline 2-1 of the vacuum pumping system 2 extends into the dryer body 1, and a vacuum filter head 2-1-1 for filtering the powders in the dryer body 1 during vacuum pumping is provided at the extended end of the vacuum pipeline 2-1.

[0021] The pneumatic conveying system 3 is an existing pneumatic conveying system, including: a material conveying pipeline 3-1, a gas-solid separator, a silo with a dust collector at the top, and a Roots blower. The Roots blower can use positive pressure or negative pressure. When using a positive pressure Roots blower, positive pressure pneumatic conveying is realized; when using a negative pressure Roots blower, negative pressure pneumatic conveying is realized. And when using a negative pressure Roots blower, an online filter also needs to be added in front of the Roots blower. When the present utility model adopts negative pressure pneumatic conveying, it realizes the discharging of materials inside the dryer body 1. When adopting positive pressure pneumatic conveying, it realizes the feeding of materials inside the dryer body 1.

[0022] In the prior art, the pneumatic conveying system is directly externally connected to the discharging port of the dryer body 1, and it is necessary to stop the machine and open the discharging butterfly valve during use. However, the present utility model combines the pneumatic conveying system with the dryer body 1 more effectively. The specific structure is: the material conveying pipeline 3-1 of the pneumatic conveying system 3 penetrates through the vacuum pipeline 2-1 of the vacuum pumping system 2 and extends into the dryer body 1. Since the vacuum pipeline 2-1 does not rotate with the dryer body 1 during the operation of the dryer body 1, the material conveying pipeline 3-1 of the pneumatic conveying system 3 is embedded in the vacuum pipeline 2-1, and the material conveying pipeline 3-1 does not rotate either, which is beneficial to the stable conveying of materials. And the material can be conveyed even when the dryer body 1 is still rotating, which is beneficial to the continuous operation of the double-cone rotary vacuum dryer and improves the working efficiency.

[0023] In order to facilitate the feeding and discharging of powder materials, a collecting hood 3-1-1 is provided at one end of the material conveying pipeline 3-1 extending into the dryer body 1. The collecting hood 3-1-1 is in a horn shape with the horn opening facing downwards. When feeding, the collecting hood 3-1-1 is used to facilitate uniform feeding; when discharging, the area of the collecting hood 3-1-1 is larger, which is beneficial to sucking more materials and improving the discharging efficiency.

[0024] One end of the material conveying pipeline 3-1 extending into the dryer body 1 can also be arranged as: a hose 3-1-3.1 and a gravity suction ball 3-1-2.2. One end of the hose 3-1-2.1 is fixedly connected to the end of the material conveying pipeline 3-1, and the other end of the hose 3-1-2.1 is connected to the gravity suction ball 3-1-2.2. The sum of the length of the hose 3-1-2.1 and the length of the suction hole of the gravity suction ball 3-1-2.2 is less than the rotational radius of the inner cavity of the dryer body 1. The hose 3-1-2.1 is an industrial application hose, and generally high-elastic silicone tubes, bellows, etc. are selected. However, note that if a bellows is selected, it is necessary to ensure that the sum of the maximum tensile length of the bellows and the length of the suction hole of the gravity suction ball is less than the rotational radius of the inner cavity of the dryer body 1. With such a setting, when the dryer body 1 stops rotating and discharging materials, the direction where the gravity suction ball 3-1-2.2 stops is always at the lower end of the inner cavity of the dryer body 1. At this time, the powder also accumulates at the lower end of the inner cavity of the dryer body 1, and the gravity suction ball 3-1-2.2 falls into the interior of the powder. Then, starting the pneumatic conveying system to discharge materials can ensure the continuity of discharging materials.

[0025] Since the double-cone rotary vacuum dryer is in a vacuum state during operation, if pneumatic conveying of materials is carried out during the operation of the dryer body 1, it is necessary to ensure the vacuum degree in the dryer body 1 and balance the air pressure in the dryer body 1. To achieve this purpose, the double-cone rotary vacuum dryer of the present invention further includes a gas balance system. The gas balance system includes: a gas conveying pipeline 4-1, a gas supplementing device 4-2, and an air extraction device 4-3. Generally, an air compressor can be selected as the gas supplementing device 4-2. When feeding materials through pneumatic conveying, the excess gas in the dryer body 1 is extracted through the gas balance system 4; when discharging materials through pneumatic conveying, the gas balance system supplies gas to the dryer body 1. The above two processes are both to ensure the air pressure balance inside the dryer body 1 during operation.

[0026] One end of the gas conveying pipeline 4-1 penetrates through the vacuum pipeline 2-1 of the vacuum pumping system 2 and extends into the dryer body 1; the other end of the gas conveying pipeline 4-1 is respectively connected to the gas supplementing device 4-2 and the air extraction device 4-3 through valves. Since the dryer body 1 contains ultra-fine powder, when extracting air, some powder will inevitably be sucked into the gas conveying pipeline 4-1. When the air extraction device 4-3 exhausts gas, it will cause dust pollution. To avoid this problem, an air extraction filter screen 4-1-1 that intercepts the powder inside is provided at one end of the gas conveying pipeline 4-1 connected to the air extraction device 4-3.

[0027] Generally, valves are provided on all pipelines. In the present utility model, a vacuum valve 2-1-2 is provided on the vacuum pipeline 2-1 of the vacuum system 2; a material valve 3-1-3 is provided on the material conveying pipeline of the pneumatic conveying system 3; an air supplement valve 4-2-1 is provided at one end where the gas conveying pipeline 4-1 is connected to the air supplement device 4-2, and an air extraction valve 4-3-1 is provided at one end where the gas conveying pipeline 4-1 is connected to the air extraction device 4-3.

[0028] When using the present utility model for pneumatic conveying of materials, the specific process operations of the above valves are shown in Table 1:

[0029] Table 1. Application of valves in the operation process of the present utility model

[0030] Process Vacuum valve Material valve Gas supplementing valve Air extraction valve Drying Open Close Close Close Feeding Close Open Close Open Discharging Close Open Open Close

[0031] The existing double-cone rotary vacuum dryer controls the operation of each system through an electric control system. An improvement in this embodiment is: an electric control system for controlling the operation of the double-cone rotary vacuum dryer is provided, and the dryer body 1, the vacuum pumping system 2, the pneumatic conveying system 3, the gas balance system 4, etc. are all electrically connected to the electric control system to achieve process automation.

[0032] Since the existing electric control system can control all operations on the double-cone rotary vacuum dryer, when setting up the electric control system of the present utility model, the operations of the pneumatic conveying system and the air supplement system can be integrated into the original electric control system to realize the automatic control of the double-cone rotary vacuum dryer of the present utility model, which saves more manpower.

Claims

1. A double cone rotary vacuum dryer comprising: The dryer body, the vacuum system and the pneumatic conveying system, the vacuum pipeline of the vacuum system extends to the inside of the dryer body, and the extended end of the vacuum pipeline is provided with a vacuum filter head for filtering the powder in the dryer body during vacuuming; the material conveying pipeline of the pneumatic conveying system is connected to the dryer body; It is characterized in that The material conveying pipeline (3-1) of the pneumatic conveying system (3) passes through the vacuum pipeline (2-1) of the vacuum pumping system (2) and extends to the interior of the dryer body (1); The double-cone rotary vacuum dryer further comprises: a gas balance system; The gas balance system comprises: a gas delivery pipeline (4-1), a gas supply device (4-2) and a gas extraction device (4-3); one end of the gas delivery pipeline (4-1) passes through the vacuum pipeline (2-1) of the vacuum extraction system (2) and extends to the interior of the dryer body (1); the other end of the gas delivery pipeline (4-1) is connected to the gas supply device (4-2) and the gas extraction device (4-3) via valves.

2. A double cone rotary vacuum dryer according to claim 1, characterized in that: One end of the material conveying pipeline (3-1) extending to the interior of the dryer body (1) is provided with a material collecting cover (3-1-1).

3. A double cone rotary vacuum dryer according to claim 1, characterized in that: The material conveying pipeline (3-1) extends to one end of the dryer body (1) and is provided with: a hose (3-1-2.1) and a gravity suction ball (3-1-2.2); one end of the hose (3-1-2.1) is fixedly connected to the end of the material conveying pipeline (3-1), and the other end of the hose (3-1-2.1) is connected to the gravity suction ball (3-1-2.2); the sum of the length of the hose (3-1-2.1) and the length of the suction hole of the gravity suction ball (3-1-2.2) is less than the rotation radius of the inner cavity of the dryer body (1).

4. A double cone rotary vacuum dryer according to claim 1, characterized in that: One end of the gas delivery pipeline (4-1) that is connected to the gas extraction device (4-3) is provided with a gas extraction filter (4-1-1) that intercepts the powder.

5. A double cone rotary vacuum dryer according to claim 1, characterized in that: The double-cone rotary vacuum dryer further comprises: a frame (5); the dryer body (1) is mounted on the frame (5).

6. A double cone rotary vacuum dryer according to claim 5, characterized in that: The frame (5) is a movable frame.

7. A double cone rotary vacuum dryer according to claim 1, characterized in that: The double-cone rotary vacuum dryer also includes: an electric control system for controlling the operation of the double-cone rotary vacuum dryer, and the dryer body (1), vacuum pumping system (2), pneumatic conveying system (3), and gas balance system (4) are all electrically connected to the electric control system.

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