Pneumatic conveying device and heat power unit

Abstract

The invention discloses a pneumatic conveying device and a heat power unit. The pneumatic conveying device comprises a first pipe, a second pipe, a material conveying assembly and a valve body. The first pipe is provided with a first channel, the second pipe is provided with a second channel, the second channel is provided with a feed port and a discharge port, and a blanking pipe is arranged between the second channel and the first channel; the material conveying assembly is arranged in the second pipe, and the valve body is arranged in the first channel and located on the side, close to the feeding port, of the material falling pipe. The end, close to the first channel, of the blanking pipe is provided with a first expansion section, and the sectional area, orthogonal to the axial direction of the blanking pipe, of the first expansion section is gradually increased in the flowing direction of materials in the blanking pipe. According to the embodiment of the invention, airflow parameters can be matched with the characteristics of the solid waste material, and meanwhile, the structure of the first expansion section of the blanking pipe can be utilized to reduce the pressure of a local area, improve the gathering effect of the solid waste material and a pneumatic conveying medium and improve the pneumatic conveying efficiency.

Description

Technical Field

[0001] This invention belongs to the field of material conveying technology, and specifically relates to a pneumatic conveying device and a thermal unit. Background Technology

[0002] Waste textiles, sponges, waste chemical fibers, and other lightweight industrial solid wastes all have a certain calorific value and can be used as alternative fuels in the heating industry. However, in the pneumatic conveying process, due to the significant differences in shape, density, and bulkiness between solid wastes and coal, problems such as low conveying efficiency and large fluctuations in conveying volume per unit time often occur. During pneumatic conveying, the pneumatic conveying medium and solid wastes cannot effectively merge, making it difficult to achieve efficient conveying of solid wastes and limiting their application in thermal units such as pulverized coal boilers. Summary of the Invention

[0003] The present invention aims to at least partially solve one of the technical problems in the related art.

[0004] Therefore, embodiments of the present invention propose a pneumatic conveying device with high conveying efficiency and good stability.

[0005] An embodiment of the present invention provides a thermal power unit.

[0006] The pneumatic conveying device of this invention includes: The first pipe has a first channel, which has an air inlet and an air outlet. The air inlet of the first channel is used to connect to a gas supply device, and the air outlet of the first channel is used to connect to a heating device. The second pipe has a second channel, which has an inlet and an outlet. A discharge pipe is provided between the second channel and the first channel of the first pipe through the outlet. A material conveying assembly disposed inside the second tube to convey material added into the second channel from the inlet to the outlet. A valve body is disposed in the first channel and located upstream of the material discharge pipe to adjust the airflow parameters in the first channel; The end of the discharge pipe adjacent to the first channel has a first expansion section, and the cross-sectional area of ​​the first expansion section orthogonal to the axial direction of the discharge pipe gradually increases along the material flow direction in the discharge pipe.

[0007] The pneumatic conveying device of this invention can control parameters such as pressure and flow rate of the pneumatic conveying medium in the first channel through the valve body, thereby matching the airflow parameters with the characteristics of the solid waste material. At the same time, the structure of the first expansion section of the discharge pipe can be used to reduce the pressure in the local area, improve the convergence effect of the solid waste material and the pneumatic conveying medium, and improve the efficiency of pneumatic conveying.

[0008] In some embodiments, the end of the discharge pipe adjacent to the second channel has a second expansion section, the cross-sectional area of ​​the second expansion section orthogonal to the axial direction of the discharge pipe gradually decreasing along the material flow direction in the discharge pipe.

[0009] In some embodiments, the cross section of the first expansion section adjacent to the first channel, orthogonal to the axial direction of the discharge tube, is a first cross section, and the cross section area of ​​the second expansion section adjacent to the second channel, orthogonal to the axial direction of the discharge tube, is a second cross section, wherein the area of ​​the first cross section is greater than the area of ​​the second cross section.

[0010] In some embodiments, the length of the first expansion section in the axial direction of the discharge tube is smaller than the length of the second expansion section in the axial direction of the discharge tube.

[0011] In some embodiments, a baffle is further included, the baffle being disposed within the first channel, the first tube having a feeding port communicating with the discharge tube, the baffle being located upstream of the feeding port, and the free end of the baffle extending below the feeding port.

[0012] In some embodiments, the baffle is inclined, and a contraction section is formed between the baffle and the inner wall of the first channel, the cross-sectional area of ​​the contraction section gradually decreasing along the airflow direction in the first channel.

[0013] In some embodiments, the free end of the baffle does not extend beyond the middle of the feed port in the airflow direction within the first channel.

[0014] In some embodiments, an air inlet is further included, which is disposed on the side wall of the discharge pipe. An air inlet chamber is formed between the baffle and the side wall of the discharge pipe. The air inlet corresponds to and is connected to the air inlet chamber. The air inlet is connected to an air source, or a one-way valve is provided at the air inlet.

[0015] In some embodiments, the feeding assembly includes a driver and a feeding screw disposed in the second channel, the feeding screw being arranged along the length direction of the second channel, the driver being used to drive the feeding screw to rotate, and the feeding screw being a shaftless helical blade.

[0016] The thermal power unit of this invention includes a blower, a thermal power unit, a continuous conveying device for lightweight materials based on pneumatic conveying as described in any one of the above-mentioned embodiments, and a coal conveying device. The blower is connected to the air inlet end of the first pipe, and the thermal power unit is connected to the air outlet end of the first pipe to convey materials into the thermal power unit via pneumatic conveying. The coal conveying device is connected to the thermal power unit to convey coal to the thermal power unit. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a pneumatic conveying device according to an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of a pneumatic conveying device according to another embodiment of the present invention.

[0019] Figure label: 1. First pipe; 11. First channel; 2. Second pipe; 21. Second channel; 22. Inlet; 23. Outlet; 3. Conveying assembly; 31. Conveying screw; 4. Feed pipe; 41. First expansion section; 42. Second expansion section; 43. Air inlet; 5. Baffle; 51. Contraction section; 52. Intake chamber; 6. Valve body. Detailed Implementation

[0020] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0021] See Figure 1 and Figure 2 The pneumatic conveying device of this invention includes a first pipe 1, a second pipe 2, a material conveying assembly 3, and a valve body 6.

[0022] The first pipe 1 serves as a pneumatic conveying pipeline. Gas at a certain pressure and flow rate is blown into the first pipe 1, thereby conveying materials by pneumatically carrying them along the inner cavity of the first pipe 1. The first pipe 1 has a first channel 11, which has an air inlet and an air outlet. The air inlet of the first channel 11 is used to connect to a gas supply device, which can be a blower, such as a centrifugal fan. The pneumatic conveying medium in the first pipe 1 can be air or boiler flue gas. Preferably, boiler flue gas that has been dusted and cooled to a certain extent can be used. The oxygen content in the boiler flue gas is relatively low, which can prevent combustion and explosion when the material is conveyed by an open flame. The air outlet of the first channel 11 is used to connect to a thermal device. The thermal device can be a coal-fired boiler. In this embodiment, the fuel used in the coal-fired boiler is not limited. It can be used to convey light industrial solid waste materials such as waste textiles, sponges, and waste chemical fibers, or it can be used as fuel to convey materials into the coal-fired boiler.

[0023] The second pipe 2 is used to transport solid waste materials into the first channel 11 of the first pipe 1, and then transport them over a long distance through the first pipe 1. The second pipe 2 has a second channel 21, which has an inlet 22 and an outlet 23. A discharge pipe 4 is provided between the second channel 21 and the first channel 11 of the first pipe 1 through the outlet 23. The conveying assembly 3 is located in the second pipe 2 to convey the material added into the second channel 21 by the inlet 22 to the outlet 23. The valve body 6 is located in the first channel 11 and upstream of the discharge pipe 4 to adjust the airflow parameters in the first channel 11. At this time, the pneumatic conveying medium first passes through the valve body 6 and then through the lower port of the discharge pipe 4. The end of the discharge pipe 4 adjacent to the first channel 11 has a first expansion section 41. The cross-sectional area of ​​the first expansion section 41, which is orthogonal to the axial direction of the discharge pipe 4, gradually increases along the material flow direction in the discharge pipe 4.

[0024] In this embodiment, by setting the valve body 6, the airflow parameters such as the pressure and flow rate of the pneumatic conveying medium flowing through the connection between the material drop pipe 4 and the first pipe 1 can be adjusted. This makes the airflow parameters match the density, bulkiness, particle size and other parameters of the solid waste material, ensuring that the solid waste material can flow smoothly into the pneumatic conveying medium and be efficiently conveyed under the action of the pneumatic conveying medium.

[0025] The first expansion section 41 can increase the cross-sectional area of ​​the end of the discharge pipe 4 adjacent to the first channel 11. When the solid waste material moves from the end of the discharge pipe 4 adjacent to the second channel 21 to the end adjacent to the first channel 11, the solid waste material can be fully mixed with the pneumatic conveying medium in a larger space, thereby improving the pneumatic conveying efficiency.

[0026] The pneumatic conveying device of this invention can control parameters such as pressure and flow rate of the pneumatic conveying medium in the first channel 11 through the valve body 6, so that the airflow parameters match the characteristics of the solid waste material. At the same time, the structure of the first expansion section 41 of the discharge pipe 4 can be used to reduce the pressure in the local area, improve the convergence effect of the solid waste material and the pneumatic conveying medium, and improve the efficiency of pneumatic conveying.

[0027] In some embodiments, the end of the discharge pipe 4 adjacent to the second channel 21 has a second expansion section 42, and the cross-sectional area of ​​the second expansion section 42 orthogonal to the axial direction of the discharge pipe 4 gradually decreases along the material flow direction in the discharge pipe 4. In this embodiment, the first expansion section 41 is generally the lower half of the discharge pipe 4, and the second expansion section 42 is generally the upper half of the discharge pipe 4. In the material flow direction in the discharge pipe 4, the cross-sectional area of ​​the upper half gradually decreases, and the cross-sectional area of ​​the lower half gradually increases. That is to say, the cross-sectional area of ​​the generally central region of the discharge pipe 4 is the smallest, which can make the material relatively dense and prevent gas from flowing into the second channel 21.

[0028] The structure of the discharge pipe 4 in this embodiment facilitates the material from the second channel 21 to fall into the discharge pipe 4, and at the same time facilitates the material from the discharge pipe 4 to flow into the first channel 11, thereby improving the smoothness of the material flow in the discharge pipe 4, improving the uniformity of pneumatic conveying, and making it easier to control the flow rate of solid waste materials, so as to achieve stable material supply for thermal equipment.

[0029] In some embodiments, the cross-section of the first expansion section 41, adjacent to one end of the first channel 11 and orthogonal to the axial direction of the discharge pipe 4, is the first cross-section, and the cross-sectional area of ​​the second expansion section 42, adjacent to one end of the second channel 21 and orthogonal to the axial direction of the discharge pipe 4, is the second cross-section, with the area of ​​the first cross-section being larger than the area of ​​the second cross-section. In other words, in this embodiment, the cross-sectional area of ​​the lower end of the discharge pipe 4 is larger than the cross-sectional area of ​​the upper end of the discharge pipe 4, thereby ensuring that the material flows out of the discharge pipe 4 more easily, avoiding the accumulation of material inside the discharge pipe 4, and at the same time, making the density of the upper half of the discharge pipe 4 greater than the density of the lower half of the discharge pipe 4, making it easier for the pneumatic conveying medium to mix with the material.

[0030] In this embodiment, the air pressure in the discharge pipe 4 changes in a gradient, which can better prevent gas from flowing into the second channel 21 and avoid interfering with the material conveying in the second channel 21.

[0031] This embodiment eliminates the need for feeders or other equipment within the discharge pipe 4, improving discharge efficiency, enhancing practicality, increasing conveying efficiency, lowering modification costs for existing equipment, and improving usability.

[0032] In some embodiments, the length of the first expansion section 41 in the axial direction of the discharge pipe 4 is smaller than the length of the second expansion section 42 in the axial direction of the discharge pipe 4. It is understood that the length B of the first expansion section 41 is less than half the total length of the discharge pipe 4, while the length A of the second expansion section 42 is greater than half the total length of the discharge pipe 4. This allows the second expansion section 42 to accommodate more material, inhibiting the pneumatic conveying medium from flowing into the second channel 21. A small-scale vortex can be formed at the location of the pneumatic conveying stop at the first expansion section 41, thereby facilitating efficient mixing of the material and the pneumatic conveying medium and improving the efficiency and effectiveness of the pneumatic conveying.

[0033] In some embodiments, the pneumatic conveying device further includes a baffle 5 disposed within the first channel 11. The first pipe 1 has a feeding port communicating with the discharge pipe 4. The baffle 5 is located upstream of the feeding port, and the free end of the baffle 5 extends below the feeding port. In this embodiment, the feeding port is also the lower end of the discharge pipe 4. The connection between the baffle 5 and the first pipe 1 is located upstream of the feeding port, and the free end of the baffle 5 extends below the feeding port. Thus, a portion of the baffle 5 overlaps with the feeding port axially, thereby suppressing the flow of the pneumatic conveying medium into the discharge pipe 4, changing the airflow state at the lower end of the discharge pipe 4, and facilitating the material to fall more easily.

[0034] Furthermore, the baffle 5 is inclined, and a contraction section 51 is formed between the baffle 5 and the inner wall of the first channel 11. The cross-sectional area of ​​the contraction section 51 gradually decreases along the airflow direction within the first channel 11. This increases the airflow velocity at that location and simultaneously creates a negative pressure at the lower end of the discharge pipe 4, generating a Venturi effect. This achieves negative pressure suction of the material within the discharge pipe 4, increasing the material flow velocity, improving the mixing effect between the material and the pneumatic conveying medium, and resulting in higher conveying efficiency.

[0035] Optionally, the free end of the baffle 5 does not exceed the middle of the feed port in the airflow direction within the first channel 11. This avoids excessive obstruction of the lower port of the discharge pipe 4 by the baffle 5, ensuring that the material in the discharge pipe 4 can fall smoothly.

[0036] In some embodiments, an air inlet 43 is also included. The air inlet 43 is disposed on the side wall of the discharge pipe 4. An air inlet cavity 52 is formed between the baffle 5 and the side wall of the discharge pipe 4. The air inlet 43 corresponds to and is connected to the air inlet cavity 52. ​​The air inlet 43 is connected to an air source, or a one-way valve is provided at the air inlet 43. Although there is an air inlet cavity 52 above the baffle 5 in this embodiment, material will not accumulate in this area. Even if material accumulates, it will form a slope that guides the flow of gas after filling the area of ​​the air inlet cavity 52. ​​The air inlet cavity 52 will also form a negative pressure state here due to the Venturi effect. In this embodiment, by setting the air inlet 43, the external airflow can actively flow into the air inlet cavity 52 and cause the material at the lower end of the discharge pipe 4 to flow into the first channel 11.

[0037] In this embodiment, by setting a one-way valve at the air inlet 43, the airflow can only flow from the outside to the inside, and not from the inside to the outside.

[0038] When the air inlet 43 of this embodiment is connected to the air source, the air pressure and speed can be actively controlled. For example, when material blockage occurs, the material drop pipe 4 can be cleared by pulsed airflow to avoid material jamming and improve the smoothness of material drop.

[0039] In some embodiments, the conveying assembly 3 includes a driver and a conveying screw 31 disposed within the second channel 21. The conveying screw 31 is arranged along the length of the second channel 21. The driver drives the conveying screw 31 to rotate. The conveying screw 31 is a shaftless helical blade. The driver can be a motor, and the conveying screw 31 can be a shaftless helical blade. The shaftless screw arrangement within the second channel 21 allows for more space to be reserved within the second channel 21, facilitating improvements in material conveying capacity and efficiency.

[0040] The thermal power unit of this invention includes a blower, a thermal power unit, a pneumatically based continuous conveying device for lightweight materials, and a coal conveying device. The blower is connected to the air inlet of a first pipe 1, and the thermal power unit is connected to the air outlet of the first pipe 1 to convey materials into the thermal power unit via pneumatic conveying. The coal conveying device is connected to the thermal power unit to convey coal to the thermal power unit. The blower can be a centrifugal fan, and the thermal power unit can be a coal-fired boiler. In this embodiment, the coal-fired boiler is equipped with a coal conveying device for conveying coal and a pneumatically based continuous conveying device for conveying solid waste fuel, thereby achieving coupling with the coal-fired boiler and realizing the utilization of lightweight industrial solid waste materials such as waste textiles, sponges, and waste chemical fibers, thus realizing the value utilization of solid waste materials.

[0041] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to 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 invention.

[0042] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0043] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0044] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0045] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0046] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A pneumatic conveying device, characterized in that, include: The first pipe has a first channel, which has an air inlet and an air outlet. The air inlet of the first channel is used to connect to a gas supply device, and the air outlet of the first channel is used to connect to a heating device. The second pipe has a second channel, which has an inlet and an outlet. A discharge pipe is provided between the second channel and the first channel of the first pipe through the outlet. A material conveying assembly disposed inside the second tube to convey material added into the second channel from the inlet to the outlet. A valve body is disposed in the first channel and located upstream of the material discharge pipe to adjust the airflow parameters in the first channel; The end of the discharge pipe adjacent to the first channel has a first expansion section, and the cross-sectional area of ​​the first expansion section orthogonal to the axial direction of the discharge pipe gradually increases along the material flow direction in the discharge pipe.

2. The pneumatic conveying device according to claim 1, characterized in that, The end of the discharge pipe adjacent to the second channel has a second expansion section, and the cross-sectional area of ​​the second expansion section orthogonal to the axial direction of the discharge pipe gradually decreases along the material flow direction in the discharge pipe.

3. The pneumatic conveying device according to claim 2, characterized in that, The cross section of the first expansion section, which is adjacent to the first channel and is orthogonal to the axial direction of the discharge pipe, is the first cross section. The cross section area of ​​the second expansion section, which is adjacent to the second channel and is orthogonal to the axial direction of the discharge pipe, is the second cross section. The area of ​​the first cross section is greater than the area of ​​the second cross section.

4. The pneumatic conveying device according to claim 2, characterized in that, The length of the first expansion section in the axial direction of the discharge tube is smaller than the length of the second expansion section in the axial direction of the discharge tube.

5. The pneumatic conveying device according to any one of claims 1 to 4, characterized in that, It also includes a baffle plate disposed in the first channel. The first pipe has a feeding port that communicates with the discharge pipe. The baffle plate is located upstream of the feeding port, and the free end of the baffle plate extends to the bottom of the feeding port.

6. The pneumatic conveying device according to claim 5, characterized in that, The baffle is inclined, and a contraction section is formed between the baffle and the inner wall of the first channel. The cross-sectional area of ​​the contraction section gradually decreases along the airflow direction in the first channel.

7. The pneumatic conveying device according to claim 6, characterized in that, The free end of the baffle does not exceed the middle of the feed port in the airflow direction within the first channel.

8. The pneumatic conveying device according to claim 6, characterized in that, It also includes an air inlet, which is located on the side wall of the discharge pipe. An air inlet chamber is formed between the baffle and the side wall of the discharge pipe. The air inlet corresponds to and is connected to the air inlet chamber. The air inlet is connected to an air source, or a one-way valve is provided at the air inlet.

9. The pneumatic conveying device according to claim 1, characterized in that, The material conveying assembly includes a driver and a material conveying screw disposed in the second channel. The material conveying screw is arranged along the length direction of the second channel. The driver is used to drive the material conveying screw to rotate. The material conveying screw is a shaftless helical blade.

10. A thermal power unit, characterized in that, The device includes a blower, a heating device, a continuous conveying device for lightweight materials based on pneumatic conveying as described in any one of claims 1 to 9, and a coal conveying device. The blower is connected to the air inlet end of the first pipe, the heating device is connected to the air outlet end of the first pipe, so as to convey materials into the heating device by pneumatic conveying, and the coal conveying device is connected to the heating device to convey coal to the heating device.

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