Static vertical dryer utilizing flue gas waste heat

Abstract

The utility model belongs to smelting slag drying equipment technical field, specifically disclose a static vertical dryer of utilizing flue gas waste heat, including inner casing, outer casing and the interlayer of inner and outer casing, be equipped with several stages heat exchange unit in the upper and lower interval in inner casing cavity, every stage heat exchange unit includes a group of upper cloth distribution board and lower cloth distribution board of upper and lower interval arrangement respectively, be provided with the air channel that extends spirally in upper cloth distribution board and lower cloth distribution board respectively, work, flue gas first from flue gas entrance into interlayer, then along heat exchange unit inner air channel from below and upwards movement from flue gas export, material from material import enters inner casing cavity, falls on upper cloth distribution board, lower cloth distribution board, after completing heat exchange drying, material from material export, material from above and downwards movement while the moisture in material endothermic evaporation becomes water vapour from water vapour export, can with water content 20%~30% indirect drying of slag to water content <10%, facilitate slag warehousing and external transport.

Description

Technical Field

[0001] This utility model belongs to the technical field of smelting slag drying equipment, specifically disclosing a static vertical dryer that utilizes waste heat from flue gas. Background Technology

[0002] A dryer is a mechanical device that uses heat energy to reduce the moisture content of materials. It works by heating the material to vaporize and release the moisture (water or volatile liquid), thus obtaining a material with a specified moisture content. Dryers are widely used in current industrial production. In slag powder production lines, the moisture content of the material is typically required to be <15%. Since grinding mills cannot directly process slag with a moisture content >20%, drying is usually necessary before grinding. Existing drying technologies mostly employ dynamic drying methods, such as rotary dryers or fluidized bed dryers. While dynamic drying is fast, it suffers from high energy consumption and large equipment footprint due to the poor thermal conductivity and low thermal efficiency of slag. Therefore, many companies currently use methods such as stockpiling and spreading to reduce the moisture content of slag. However, stockpiling and spreading require a large area, easily leading to dust pollution. Environmental policies prohibit open-air stockpiling, and building new stockpiling sheds would increase construction investment.

[0003] In industrial settings involving high-temperature flue gas emissions from kiln production lines, companies typically use the medium- and low-temperature flue gas generated after heat exchange as a drying heat source for slag. However, direct contact between slag and flue gas can directly affect slag quality due to the inclusion of dust carried in the flue gas. For example, in the metallurgical industry, the high concentration of heavy metals such as manganese, chromium, and mercury in the flue gas prevents direct utilization of the flue gas. Instead, it can only be used after heat exchange with the flue gas, resulting in a significant loss of heat energy. Summary of the Invention

[0004] To address the problems in the background technology, this utility model discloses a static vertical dryer that utilizes waste heat from flue gas. Using the flue gas from electric furnaces or kilns in the metallurgical industry as a heat source, it can indirectly dry slag with a moisture content of 20% to 30% to a moisture content of <10%, facilitating slag storage and transportation.

[0005] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: A static vertical dryer utilizing waste heat from flue gas includes an inner shell, an outer shell surrounding the inner shell, and a sandwich layer between the inner and outer shells. A cavity is provided in the middle of the inner shell. Material inlets and steam outlets, penetrating the sandwich layer and communicating with the inner shell cavity, are spaced apart at the top of the outer shell. A material outlet, communicating with the inner shell cavity, is provided at the bottom of the inner shell. A flue gas outlet, penetrating the sandwich layer and communicating with the inner shell cavity, is provided on the upper part of the side wall of the outer shell. A flue gas inlet, communicating with the sandwich layer, is provided on the lower part of the side wall of the outer shell. Several stages of heat exchange units are spaced vertically within the inner shell cavity. Each heat exchange unit includes a set of upper and lower material distribution plates spaced vertically. The upper and lower material distribution plates have a conical structure. The large-diameter end of the upper material distribution plate is positioned opposite to the large-diameter end of the lower material distribution plate. The radius of the large-diameter end of the upper material distribution plate is smaller than that of the large-diameter end of the lower material distribution plate. The small-diameter end of the upper material distribution plate is closed, while both ends of the lower material distribution plate are open. Spiral-shaped air passages are provided inside the upper and lower material distribution plates respectively. The air passage at the large-diameter end of the upper material distribution plate is connected to the air passage at the large-diameter end of the lower material distribution plate in the same group through a second connecting pipe. The air passage at the small-diameter end of the upper material distribution plate is connected to the air passage at the small-diameter end of the lower material distribution plate of the adjacent heat exchange unit above through a first connecting pipe. In the uppermost heat exchange unit, the air passage at the small-diameter end of the upper material distribution plate is connected to the flue gas outlet through an exhaust pipe. In the lowermost heat exchange unit, the air passage at the small-diameter end of the lower material distribution plate is connected to the interlayer through an intake pipe.

[0006] Furthermore, in the static vertical dryer that utilizes waste heat from flue gas, the second connecting pipe and the first connecting pipe are respectively installed in the interlayer.

[0007] Furthermore, the static vertical dryer utilizing waste heat from flue gas also includes several compressed air tanks disposed outside the outer shell. The number of compressed air tanks is a multiple of the sum of the number of upper and lower feeding plates. Several spray holes extending along the feeding direction are respectively provided on the material dropping surfaces of the upper and lower feeding plates. The air outlets of the compressed air tanks are respectively connected to the air inlet ends of the spray holes through air pipes penetrating the inner and outer shells and the interlayer.

[0008] Furthermore, the static vertical dryer utilizing waste heat from flue gas has at least two stages of heat exchange units spaced vertically in the inner shell cavity.

[0009] Furthermore, in the static vertical dryer that utilizes waste heat from flue gas, the material inlet and material outlet are aligned with the upper and lower material distribution plates on the same straight line.

[0010] Furthermore, in the static vertical dryer that utilizes waste heat from flue gas, the steam outlet is connected to a dust collector and a fan located outside the dryer via a pipeline, the flue gas inlet is connected to the existing flue gas pipeline in the plant area, and the flue gas outlet is connected to a flue gas treatment system and a fan located outside the dryer via a pipeline.

[0011] Compared with the prior art, the beneficial effects of this utility model are: This utility model relates to a static vertical dryer utilizing waste heat from flue gas. It includes an inner shell, an outer shell surrounding the inner shell, and a sandwich layer between the inner and outer shells. Several heat exchange units are spaced vertically within the cavity of the inner shell. Each heat exchange unit includes an upper and lower distribution plate spaced vertically. Both the upper and lower distribution plates are conical structures. Spiral-shaped air ducts are provided in the middle of the upper and lower distribution plates. During operation, flue gas first enters the sandwich layer through the flue gas inlet, heating the inner shell wall. Then, the flue gas moves upwards along the air ducts and exits through the flue gas outlet. Material enters the inner shell through the top material inlet. The material falls onto the upper and lower cloth plates in the cavity of the body. It moves from top to bottom by relying on its own weight, friction between materials, and friction between materials and cloth plates. After heat exchange and drying, the material is discharged from the material outlet. While the material moves from top to bottom, the moisture in the material absorbs heat and evaporates into water vapor, which is discharged through the water vapor outlet. After being treated by an external dust collector and fan, it is discharged after meeting the standards. This utility model is a static vertical dryer that utilizes the waste heat of flue gas. It can indirectly dry slag with a moisture content of 20% to 30% to a moisture content of <10%, which is convenient for slag storage and transportation, and saves enterprises land, fuel and construction investment. Attached Figure Description

[0012] Figure 1 This is a cross-sectional structural schematic diagram of the static vertical dryer utilizing waste heat from flue gas according to this utility model. Figure 2 This is a schematic diagram of the flue gas flow direction during the operation of the static vertical dryer utilizing waste heat of flue gas according to this utility model; Figure 3 This is a schematic diagram of the material flow direction and spraying process during the operation of the static vertical dryer utilizing waste heat of flue gas according to this utility model. In the above figure: 1-outer shell; 2-inner shell; 3-upper material distribution plate; 4-lower material distribution plate; 5-material inlet; 6-flue gas inlet; 7-material outlet; 8-flue gas outlet; 9-water vapor outlet; 10-compressed gas tank; 11-first connecting pipe; 12-second connecting pipe. Detailed Implementation

[0013] To better understand this utility model, the following embodiments further illustrate the content of this utility model, but the content of this utility model is not limited to the following embodiments.

[0014] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; "linked" can mean a mechanical connection or an electrical connection; "connected" can mean a direct connection or an indirect connection through an intermediate medium, and can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0015] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0016] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0017] Combined with appendix Figure 1-3This invention describes a static vertical dryer utilizing waste heat from flue gas, comprising an inner shell 2, an outer shell 1 encased outside the inner shell 2, and a sandwich layer between the inner and outer shells. A cavity is provided in the middle of the inner shell 2. A material inlet 5 and a steam outlet 9, penetrating the sandwich layer and communicating with the cavity of the inner shell 2, are provided at intervals on the top of the outer shell 1. The steam outlet 9 is connected to a dust collector and a fan located outside the dryer via a pipe. A material outlet 7, communicating with the cavity of the inner shell 2, is provided at the bottom of the inner shell 2. A flue gas outlet 8, penetrating the sandwich layer and communicating with the cavity of the inner shell 2, is provided on the upper side wall of the outer shell 1. The flue gas outlet 8 is connected to a flue gas treatment system located outside the dryer via a pipe. Connected to the fan, a flue gas inlet 6, communicating with the interlayer, is provided on the lower part of the side wall of the outer shell 1. The flue gas inlet 6 is connected to the existing flue gas pipeline in the plant area. Several stages of heat exchange units are arranged vertically and vertically in the cavity of the inner shell 2. Each stage of heat exchange unit includes a set of upper and lower distribution plates 3 and 4 arranged vertically and vertically. Both the upper distribution plate 3 and the lower distribution plate 4 are conical structures. The large-diameter end of the upper distribution plate 3 is opposite to the large-diameter end of the lower distribution plate 4. The radius of the large-diameter end of the upper distribution plate 3 is smaller than the radius of the large-diameter end of the lower distribution plate 4. The small-diameter end of the upper distribution plate 3 is closed, and both ends of the lower distribution plate 4 are open. Spiral air passages are respectively provided in the middle of the upper distribution plate 3 and the lower distribution plate 4. Figure 3 As shown, after entering through material inlet 5, the material first falls onto the outer conical surface of the upper distribution plate 3 in the uppermost heat exchange unit, then onto the inner conical surface of the lower distribution plate 4 in the uppermost heat exchange unit, and so on, until the material is discharged from material outlet 7. The outer conical surface of the upper distribution plate 3 and the inner conical surface of the lower distribution plate 4 are the material dropping surfaces. The structural design of the upper distribution plate 3 and the lower distribution plate 4 facilitates the falling of the material and increases the contact area between the material and the upper distribution plate 3 and the lower distribution plate 4. It should be noted that the upper distribution plate 3 and the lower distribution plate 4 can also be configured as a spiral structure, with some sections of the upper distribution plate 3 and the lower distribution plate 4 extending along their axial direction. The air passages are extended, but the material feeding efficiency of the upper and lower material distribution plates 3 and 4 with the spiral structure is less than that of the upper and lower material distribution plates 3 and 4 with the conical structure. The large-diameter end air passage of the upper material distribution plate 3 is connected to the large-diameter end air passage of the lower material distribution plate 4 in the same group through the second connecting pipe 12. The small-diameter end air passage of the upper material distribution plate 3 is connected to the small-diameter end air passage of the lower material distribution plate 4 of the adjacent heat exchange unit above through the first connecting pipe 11. The small-diameter end air passage of the upper material distribution plate 3 in the uppermost heat exchange unit is connected to the flue gas outlet 8 through the exhaust pipe. The small-diameter end air passage of the lower material distribution plate 4 in the lowermost heat exchange unit is connected to the interlayer through the intake pipe. At work, such as Figure 2 and Figure 3As shown, the flue gas first enters the interlayer through the flue gas inlet 6, heating the wall of the inner shell 2. Then, the flue gas sequentially enters the lower distribution plate 4 and upper distribution plate 3 in the lowest heat exchange unit, then enters the lower distribution plate 4 and upper distribution plate 3 in the next higher heat exchange unit, and so on. Finally, after passing through the lower distribution plate 4 and upper distribution plate 3 in the highest heat exchange unit, it exits through the flue gas outlet 8. The cavity of the inner shell 2 serves as a material channel. The material enters the cavity of the inner shell 2 through the top material inlet 5. The material falls on the dropping surfaces of the upper distribution plate 3 and lower distribution plate 4, contacting the side walls of the upper distribution plate 3 and lower distribution plate 4 of the heat exchange unit. It is heated by the material's own weight, the friction between materials, and the friction between the material and the distribution plates. The material moves from top to bottom, increasing the residence time of the material and fully completing the heat exchange. Finally, after drying, the material is discharged from the material outlet 7. While the material moves from top to bottom, the moisture in the material absorbs heat and evaporates into water vapor, which is discharged through the water vapor outlet 9. After being treated by an externally installed dust collector and fan, it meets the emission standards. This utility model adopts a static vertical dryer that utilizes the waste heat of flue gas. It uses the flue gas from electric furnaces or kilns in the metallurgical industry as a heat source. The flue gas temperature is 150~350℃ and the dust concentration is ≤5g / m³. It can indirectly dry slag with a moisture content of 20%~30% to a moisture content of <10%, which facilitates slag storage and transportation and saves enterprises land, fuel and construction investment. This utility model adopts a double-layer structure with inner and outer shells. The sandwich layer and the upper and lower material distribution plates 3 and 4 are equipped with unidirectional annular spiral flue gas channels, which not only increases the heat exchange area, but also ensures that the flue gas does not come into contact with the material, avoids pollution from heavy metal dust, ensures that the material is heated evenly, and improves the heat exchange efficiency. The air passage design of each heat exchange unit optimizes the airflow distribution, reduces heat loss, and enhances the overall heat exchange performance.

[0018] As an optional design, the preferred static vertical dryer utilizing waste heat from flue gas has the second connecting pipe 12 and the first connecting pipe 11 respectively installed in the interlayer. Both the second connecting pipe 12 and the first connecting pipe 11 are unidirectional flue gas channels, making full use of the heat of the flue gas in the interlayer to heat the second connecting pipe 12 and the first connecting pipe 11, reducing heat loss and enhancing the overall heat exchange performance.

[0019] As an optional design, the preferred static vertical dryer utilizing waste heat from flue gas further includes several compressed air tanks 10 disposed outside the outer shell 1. The number of compressed air tanks 10 is a multiple of the sum of the number of upper and lower distribution plates 3 and 4. Several spray holes extending along the discharge direction are respectively provided on the material discharge surfaces of the upper and lower distribution plates 3 and 4. The air outlets of the compressed air tanks 10 are connected to the air inlets of the corresponding spray holes through air pipes penetrating the inner and outer shells and the interlayer. Compressed air is sprayed onto the material discharge surfaces of the upper and lower distribution plates 3 and 4 through the compressed air tanks 10 to remove accumulated material on the material discharge surfaces of the upper and lower distribution plates 3 and 4 and to disperse the material. This achieves a sequential, bottom-up, cyclical spraying and cleaning of blockages in each heat exchange unit from the lower distribution plate 4 to the upper distribution plate 3.

[0020] As an optional design, the static vertical dryer that utilizes the waste heat of flue gas is preferred, with at least two stages of heat exchange units spaced vertically in the inner shell 2 cavity. During operation, the number of stages of the heat exchange units can be selected according to the moisture content of the slag.

[0021] As an optional design, the preferred static vertical dryer utilizing waste heat from flue gas has its material inlet 5, material outlet 7, upper distribution plate 3, and lower distribution plate 4 aligned on the same straight line. Figure 3 As shown, the slag to be dried enters the cavity of the inner shell 2 through the material inlet 5, first falls onto the side wall of the upper distribution plate 3 in the uppermost heat exchange unit, and then slides down to the side wall of the lower distribution plate 4 in the uppermost heat exchange unit. Then it passes through several heat exchange units in sequence for heat exchange and drying. The dried slag is discharged from the material outlet 7.

[0022] The working process of this utility model is as follows: The material is continuously fed through an external sealed feeding device to the material inlet 5. The material to be dried enters the cavity of the inner shell 2 through the material inlet 5, first falling onto the side wall of the upper distribution plate 3 in the uppermost heat exchange unit. Relying on its own weight, the friction between materials, and the friction between the material and the distribution plate, it falls from top to bottom onto the lower distribution plate 4. Then it falls sequentially onto the upper distribution plate 3 and the lower distribution plate 4 of the next heat exchange unit, and finally falls into the bottom of the inner shell 2. It is continuously discharged through the material outlet 7 and the externally installed sealed discharge device. After drying, the moisture content of metallurgical slag can be dried from 20% to 30% to <10%. The flue gas first enters the interlayer through the flue gas inlet 6, heating the wall of the inner shell 2. Then, the flue gas sequentially enters the air passages of the lower distribution plate 4 and the upper distribution plate 3 in the lowest heat exchange unit, and then enters the air passages of the lower distribution plate 4 and the upper distribution plate 3 in the next heat exchange unit, and so on. Finally, after passing through the air passages of the lower distribution plate 4 and the upper distribution plate 3 in the highest heat exchange unit, it is discharged from the flue gas outlet 8. The flue gas moves from bottom to top and is finally discharged through the flue gas outlet 8. The steam outlet 9 is connected to an externally installed dust collector and fan for processing. The steam discharged from the steam outlet 9 is discharged after being treated to meet the standards, while ensuring that the inside of the inner shell 2 is under negative pressure. In each heat exchange unit, the upper distribution plate 3 and the lower distribution plate 4 are equipped with two compressed air tanks 10. The compressed air tanks 10 spray gas through the spray holes to the material drop surface of the upper distribution plate 3 and the lower distribution plate 4, so as to realize the sequential spraying and cleaning from bottom to top in each heat exchange unit from the lower distribution plate 4 to the upper distribution plate 3 to prevent material accumulation.

[0023] To prevent heavy metal dust from adhering to the inner walls of the air ducts of the upper and lower distribution plates 3 and 4 after long-term use, thus reducing heat exchange efficiency, the flue gas must be treated by an external dust collector system before entering the device.

[0024] The above description is only an application implementation of this utility model, but the protection scope of this utility model is not limited thereto and cannot be used to limit the scope of rights of this utility model. Any equivalent changes made according to the technical solution of this utility model should be included within the protection scope of this utility model.

Claims

1. A static vertical dryer utilizing flue gas waste heat, characterized by: The system includes an inner shell, an outer shell surrounding the inner shell, and a sandwich layer between the inner and outer shells. A cavity is provided in the middle of the inner shell. Material inlets and steam outlets, penetrating the sandwich layer and communicating with the inner shell cavity, are spaced apart at the top of the outer shell. A material outlet, communicating with the inner shell cavity, is provided at the bottom of the inner shell. A flue gas outlet, penetrating the sandwich layer and communicating with the inner shell cavity, is provided on the upper part of the outer shell sidewall. A flue gas inlet, communicating with the sandwich layer, is provided on the lower part of the outer shell sidewall. Several stages of heat exchange units are spaced vertically within the inner shell cavity. Each heat exchange unit includes a set of upper and lower distribution plates spaced vertically. The upper and lower distribution plates are conical structures, with the larger diameter end of the upper distribution plate connected to the lower distribution plate. The plates are arranged with their large-diameter ends facing each other. The radius of the large-diameter end of the upper material plate is smaller than that of the large-diameter end of the lower material plate. The small-diameter end of the upper material plate is closed, while both ends of the lower material plate are open. Spiral-shaped air passages are provided inside the upper and lower material plates respectively. The air passage at the large-diameter end of the upper material plate is connected to the air passage at the large-diameter end of the lower material plate in the same group through a second connecting pipe. The air passage at the small-diameter end of the upper material plate is connected to the air passage at the small-diameter end of the lower material plate of the adjacent heat exchange unit above through a first connecting pipe. In the uppermost heat exchange unit, the air passage at the small-diameter end of the upper material plate is connected to the flue gas outlet through an exhaust pipe. In the lowermost heat exchange unit, the air passage at the small-diameter end of the lower material plate is connected to the interlayer through an intake pipe.

2. Static vertical drier with flue gas waste heat utilization according to claim 1, characterized by the fact that: The second connecting pipe and the first connecting pipe are respectively installed in the interlayer.

3. Static vertical drier with flue gas waste heat utilization according to claim 1 or 2, characterized in that: It also includes several compressed air tanks disposed outside the outer shell. The number of compressed air tanks is a multiple of the sum of the number of upper and lower fabric plates. Several blow holes extending along the material discharge direction are respectively provided on the material discharge surface of the upper and lower fabric plates. The air outlet of the compressed air tank is connected to the air inlet of the blow hole through an air pipe that penetrates the inner and outer shells and the interlayer.

4. Static vertical drier with flue gas waste heat utilization according to claim 3, characterized by the fact that: At least two heat exchange units are provided at vertical intervals in the inner shell cavity.

5. The static vertical dryer utilizing flue gas waste heat according to claim 3, characterized in that: The material inlet and material outlet are aligned with the upper and lower fabric plates on the same straight line.

6. The static vertical dryer utilizing flue gas waste heat according to claim 3, characterized in that: The steam outlet is connected to a dust collector and a fan located outside the dryer via a pipeline. The flue gas inlet is connected to the existing flue gas pipeline in the plant area. The flue gas outlet is connected to a flue gas treatment system and a fan located outside the dryer via a pipeline.

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