Vertical spiral powder heat exchanger

Abstract

The invention relates to the technical field of heat exchangers, and discloses a vertical spiral powder heat exchanger which comprises a shell, a jacket, a lifting screw, a heat exchange coil pipe and a collecting unit, the lifting screw and the heat exchange coil pipe are arranged in the shell, the jacket is arranged outside the shell in a sleeving mode to form a double-layer shell with the shell, and a spiral partition plate is arranged between the jacket and the shell; two ends of the heat exchange coil respectively extend out of the upper and lower ends of the double-layer shell; powder materials enter the heat exchanger through a feeding port of a top cover of the shell and are lifted through rotation of the lifting screw; a heat exchange medium enters the space between the double-layer shell and the heat exchange coil pipe through the water inlet of the jacket and the water inlet of the heat exchange coil pipe and exchanges heat with powder materials in the shell, and the powder materials subjected to heat exchange are collected to the collecting unit. The traditional fluidizing air fluidizing material is omitted, the heat exchange coil pipe and the jacket are adopted for double heat exchange, the heat exchange area is large, the retention time of the material in the heat exchanger is prolonged, and the heat exchange effect is obvious.

Description

Technical Field

[0001] The present invention relates to the technical field of heat exchangers, and particularly to a vertical spiral powder heat exchanger. Background Art

[0002] In many industrial production fields, reducing the temperature of powder materials is an important production process. For example, in the alumina roasting system, after the roasted alumina powder is cooled by multiple cooling units, the temperature is still above 250°C. It must be cooled to below 80°C by a cooling device before it can be conveyed to the alumina silo by a conveyor belt, otherwise it will affect the service life of the conveyor belt and the safety of production operations.

[0003] Currently, in the powder industry field, the commonly used cooling devices are mainly divided into two categories: horizontal and vertical. The working principle of most devices is to make the powder materials in a fluidized state inside the cooling device through fluidizing air, and use the fluidizing air and heat exchange tubes to exchange heat to achieve the cooling of the powder materials. Under such heat exchange conditions, the fluidizing air is generally returned to the system inside through the pipeline after being heated, which will cause heat loss due to heat dissipation through the outer wall of the device, and only part of the powder heat is obtained by the heat exchange medium inside the heat exchange tubes for heating. Summary of the Invention

[0004] In view of the above problems, the present invention provides a vertical spiral powder heat exchanger, which omits the traditional fluidizing air to fluidize the materials, increases the residence time of the materials inside the heat exchanger, and improves the heat exchange efficiency.

[0005] Specifically, it includes: a housing, a jacket, a feeding screw, a heat exchange coil, and a collection unit. The feeding screw and the heat exchange coil are arranged inside the housing. The jacket is sleeved outside the housing to form a double-layer housing with the housing. A spiral partition is provided between the jacket and the housing. Both ends of the heat exchange coil extend out from the upper and lower ends of the double-layer housing respectively; the powder materials enter the inside of the heat exchanger through the feeding port on the top cover of the housing and are lifted by the rotation of the feeding screw; the heat exchange medium enters between the double-layer housing and inside the heat exchange coil respectively through the water inlets of the jacket and the heat exchange coil, exchanges heat with the powder materials inside the housing, and the powder materials after heat exchange are collected into the collection unit.

[0006] A driving device is provided above the top cover of the housing. The output shaft of the driving device extends into the inside of the housing and is connected to the central axis of the feeding screw. A reduced-diameter section is provided at the bottom of the feeding screw. The lower end of the central axis is connected to the collection unit through a bearing, and the bearing is fixed to the collection unit through a bearing seat.

[0007] The collection unit includes a material receiving cone, a connecting piece, and a collection tank. The material receiving cone is connected to the double-layer housing to collect the powder materials after heat exchange; a connecting piece is provided at the discharge port of the material receiving cone and is connected to the collection tank. The upper and lower ends of the connecting piece are matched with the discharge port of the material receiving cone and the feeding port of the collection tank respectively, and a plug valve is provided on the connecting piece.

[0008] The coil inlet and coil outlet of the heat exchange coil extend from the lower end and the upper end of the double-layer shell respectively, and the heat exchange coil is fixed to the inner wall of the double-layer shell by a buckle.

[0009] The lower end of the jacket is provided with a jacket inlet, and the upper end of the jacket is provided with a jacket outlet. The heat exchange medium enters from the jacket inlet, spirally ascends through the spiral partition between the jacket and the outer shell, and flows out of the jacket through the jacket outlet. The width of the spiral partition is 20-50 mm.

[0010] A space for ensuring the fluidity of the powder material is left between the feeding screw and the heat exchange coil and between the heat exchange coil and the double-layer shell.

[0011] The numerical ratio of the cross-sectional area of the outer shell to the height of the heat exchange coil is 0.1-0.3; the numerical ratio of the pitch of the heat exchange coil to the inner diameter of the outer shell is 0.1-0.3; the numerical ratio of the pitch of the spiral partition and the feeding screw to the inner diameter of the outer shell is 0.15-0.35; the numerical ratio of the inner diameter of the heat exchange coil to the inner diameter of the outer shell is 0.05-0.1.

[0012] The present invention has the following beneficial effects and advantages: The vertical spiral powder heat exchanger of the present invention adopts mechanical spiral feeding, omitting the traditional fluidized air to fluidize the material, so that the high-temperature powder material can fully exchange heat with the fluid medium in the heat exchange coil 3 and the jacket 17, and the heat loss is small. The heat exchange coil and the jacket are used for double heat exchange, and the heat exchange area is large. The feeding function of the mechanical spiral increases the residence time of the material inside the heat exchanger, and the heat exchange effect is obvious. The overall structure of the equipment is simple, without complex components, the manufacturing cost is low, and the service life is long. The equipment occupies a small area, has low energy consumption, is green and environmentally friendly, and can improve the processing capacity by operating multiple devices simultaneously. Description of the Drawings

[0013] Figure 1 It is a three-dimensional structural schematic diagram of the vertical spiral powder heat exchanger of the present invention; Figure 2 It is a structural schematic diagram of the jacket of the present invention; Figure 3 It is a structural schematic diagram of the heat exchange coil of the present invention; Figure 4 It is a structural schematic diagram of the feeding screw of the present invention.

[0014] Among them, 1 - driving device, 2 - top cover, 3 - heat exchange coil, 4 - outer shell, 5 - feeding screw, 6 - central shaft, 7 - jacket inlet, 8 - receiving cone, 9 - gate valve, 10 - connecting piece, 11 - collecting tank, 12 - discharge port, 14 - bearing seat, 15 - spiral partition, 16 - jacket outlet, 17 - jacket, 18 - feed inlet, 19 - coil inlet, 20 - coil outlet. Detailed Implementation Manner

[0015] The present invention will be further described below in conjunction with the accompanying drawings of the specification. As Figure 1 shown, the present invention is a vertical spiral powder heat exchanger, including: a housing 4, a jacket 17, a feeding screw 5, a heat exchange coil 3, and a collection unit. The feeding screw 5 and the heat exchange coil 3 are arranged inside the housing. The jacket 17 is sleeved outside the housing 4 to form a double-layer housing with the housing 4. A spiral partition 15 is provided between the jacket 17 and the housing 4. A jacket water inlet 7 is provided at the lower end of the jacket, and a jacket water outlet 16 is provided at the upper end of the jacket. The heat exchange medium enters from the jacket water inlet 7, spirally ascends through the spiral partition 15 between the jacket and the housing, and flows out of the jacket through the jacket water outlet 16. The width of the spiral partition 15 is 20 - 50 mm.

[0016] Both ends of the heat exchange coil 3 extend out from the upper and lower ends of the double-layer housing respectively. Specifically, the coil water inlet 19 and the coil water outlet 20 of the heat exchange coil extend out from the lower end and the upper end of the double-layer housing respectively. The heat exchange coil 3 is fixed to the inner wall of the double-layer housing by a buckle. When working, the heat exchange medium flows into the heat exchange coil 3 from the bottom liquid inlet 19 and flows out from the top liquid outlet 20. The heat exchange coil 3 can be designed in sections according to needs.

[0017] Furthermore, there is sufficient space between the feeding screw and the heat exchange coil, and between the heat exchange coil and the inside of the double-layer housing to ensure the flow performance of the powder material and avoid accumulation.

[0018] A driving device 1 is provided above the housing top cover 2. The output shaft of the driving device 1 extends into the housing 4 and is connected to the central axis 6 of the feeding screw 5. The lower end of the central axis 6 is connected to the collection unit through a bearing. The bearing is fixed to the collection unit through a bearing seat 14 to ensure that the perpendicularity of the central axis 6 meets the use requirements. The rotation direction of the feeding screw 5 is positive rotation or reverse rotation. The driving device 1 drives the central axis 6 to rotate clockwise or counterclockwise to realize the feeding of the feeding screw 5. At the same time, there is a variable diameter section at the bottom of the feeding screw 5, which cooperates with the receiving cone 8 to increase the feeding effect. By changing the speed of the motor 1, the speed of the feeding screw 5 can be adjusted, and to a certain extent, the residence heat exchange time of the powder material inside the heat exchanger can be controlled.

[0019] The powder material enters the inside of the heat exchanger from the feed inlet 18 of the housing top cover 2, moves downward under the action of gravity, is scattered by the rotation of the feeding screw 5, and the feeding screw 5 feeds upward. The powder material is lifted upward from the bottom cone 8, increasing the residence time of the powder material inside the heat exchanger and improving the heat exchange effect.

[0020] The heat exchange medium enters between the double-layer housing and into the heat exchange coil 3 from the jacket water inlet 7 and the coil water inlet 19 respectively, exchanges heat with the powder material inside the housing 4, and the powder material after heat exchange is collected in the collection unit.

[0021] Further, the collection unit includes a material receiving cone 8, a connecting member 10, and a collection tank 11. The material receiving cone 8 is connected to the double-layer housing to collect the powder material after heat exchange. A connecting member 10 is provided at the discharge port of the material receiving cone 8 and connected to the collection tank 11. The upper and lower ends of the connecting member 10 are fitted with the discharge port 12 of the material receiving cone 8 and the feed port of the collection tank 11. A slide gate valve 9 is provided on the connecting member 10. The powder material is fed from the discharge port 12 into the collection tank 11, and the collection tank 11 realizes dust collection and feeding.

[0022] Furthermore, the numerical ratio of the cross-sectional area of the outer shell 4 to the height of the heat exchange coil 3 is 0.1 - 0.3; the numerical ratio of the pitch of the heat exchange coil 3 to the inner diameter of the outer shell 4 is 0.1 - 0.3; the numerical ratio of the pitch of the spiral partition 15 and the lifting screw 5 to the inner diameter of the outer shell is 0.15 - 0.35; the numerical ratio of the inner diameter of the heat exchange coil 3 to the inner diameter of the outer shell 4 is 0.05 - 0.1.

[0023] The present invention uses mechanical spiral lifting, omitting the traditional fluidized air to fluidize the material, enabling the high-temperature powder material to fully exchange heat with the fluid medium in the heat exchange coil 3 and the jacket 17, with little heat loss. Double heat exchange is adopted with the heat exchange coil and the jacket, resulting in a large heat exchange area. The lifting effect of the mechanical spiral increases the residence time of the material inside the heat exchanger, with obvious heat exchange effect. The overall structure of the equipment is simple, without complex components, with low manufacturing cost and long service life. The equipment occupies a small area, has low energy consumption, is green and environmentally friendly, and can improve the processing capacity by operating multiple devices simultaneously.

[0024] The technical solution of the present invention can not only be used for cooling alumina powder during the alumina production process, but also for cooling other high-temperature powder materials or particles, such as in the production of gypsum board and cement production.

[0025] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A vertical spiral powder heat exchanger, characterized in that, Comprising: A shell, a jacket, a feeding screw, a heat exchange coil pipe, and a collection unit. The feeding screw and the heat exchange coil pipe are arranged inside the shell. The jacket is sleeved outside the shell to form a double-layer shell with the shell. A spiral partition is provided between the jacket and the shell. Both ends of the heat exchange coil pipe extend out from the upper and lower ends of the double-layer shell respectively. Powder materials enter the interior of the heat exchanger through the feeding port on the top cover of the shell and are lifted by the rotation of the feeding screw. The heat exchange medium enters between the double-layer shells and into the heat exchange coil pipe respectively through the water inlet of the jacket and the heat exchange coil pipe, exchanges heat with the powder materials inside the shell, and the powder materials after heat exchange are collected into the collection unit.

2. The vertical spiral powder heat exchanger according to claim 1, characterized in that: A driving device is provided above the top cover of the shell. The output shaft of the driving device extends into the interior of the shell and is connected to the central axis of the feeding screw. A reduced-diameter section is provided at the bottom of the feeding screw. The lower end of the central axis is connected to the collection unit through a bearing, and the bearing is fixed to the collection unit through a bearing seat.

3. The vertical spiral powder heat exchanger according to claim 1, characterized in that: The collection unit includes a material receiving cone, a connecting piece, and a collection tank. The material receiving cone is connected to the double-layer shell to collect the powder materials after heat exchange. A connecting piece is provided at the discharge port of the material receiving cone and is connected to the collection tank. The upper and lower ends of the connecting piece are matched with the discharge port of the material receiving cone and the feeding port of the collection tank respectively, and a plug valve is provided on the connecting piece.

4. The vertical spiral powder heat exchanger according to claim 1, wherein: The coil pipe water inlet and the coil pipe water outlet of the heat exchange coil pipe extend out from the lower end and the upper end of the double-layer shell respectively, and the heat exchange coil pipe is fixed to the inner wall of the double-layer shell through a buckle.

5. The vertical spiral powder heat exchanger according to claim 1, wherein: The lower end of the jacket is provided with a jacket water inlet, and the upper end of the jacket is provided with a jacket water outlet. The heat exchange medium enters through the jacket water inlet, spirally ascends through the spiral partition between the jacket and the shell, and flows out of the jacket through the jacket water outlet. The width of the spiral partition is 20 - 50 mm.

6. The vertical spiral powder heat exchanger according to claim 1, characterized in that: A space for ensuring the fluidity of the powder materials is left between the feeding screw and the heat exchange coil pipe, and between the heat exchange coil pipe and the double-layer shell.

7. The vertical spiral powder heat exchanger according to claim 1, wherein: The numerical ratio of the cross-sectional area of the shell to the height of the heat exchange coil pipe is 0.1 - 0.3; the numerical ratio of the pitch of the heat exchange coil pipe to the inner diameter of the shell is 0.1 - 0.3; the numerical ratio of the pitch of the spiral partition and the feeding screw to the inner diameter of the shell is 0.15 - 0.35; the numerical ratio of the inner diameter of the heat exchange coil pipe to the inner diameter of the shell is 0.05 - 0.1.

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