A boiler flue gas hot air drying device for drying combustion raw materials

Abstract

The present invention discloses a boiler flue gas hot air drying device for drying combustion raw materials, which belongs to the technical field of boiler fuel processing, and includes a hot air drying tank body, in which a crushing air mixing feeding unit, a hot air feeding and drying unit and a flue gas waste heat utilization unit are arranged, and the flue gas waste heat utilization unit includes a flue gas conveying pipeline for conveying boiler flue gas. The present invention dries biomass fuel by flue gas generated by the boiler, conveys the biomass fuel by flue gas in a vertical air delivery pipe, utilizes the heat in the boiler flue gas to heat the biomass fuel during the transportation process, and takes away the moisture in the biomass fuel by the flue gas during the heating process, and designs the weight of the biomass fuel and the flue gas lift to ensure that only the fully dried biomass fuel can be conveyed to the filtering and storing slot, thereby ensuring the dryness of the boiler combustion raw materials and the boiler combustion quality.

Description

Technical Field

[0001] The invention relates to the technical field of boiler fuel processing, and in particular to a boiler flue gas hot air drying device for drying combustion raw materials. Background Art

[0002] Boilers are classified into many types according to different fuel raw materials, among which biomass boilers are boilers that use biomass energy as fuel; when biomass fuel is burned, it contains a large amount of organic matter and will produce ash, which will be discharged with the flue gas after combustion. Most of the ash in the flue gas will be settled and collected, and part of the flue gas needs to be filtered to remove the ash; in addition, the quality of biomass fuel is more uncontrollable than that of fuels such as gas and electricity. Biomass fuel often has a large water content due to storage or pre-processing. When the water content of biomass fuel is high, it will make ignition and fire more difficult, and prolong the combustion process, reduce the temperature of the combustion chamber, and increase the incomplete combustion loss and exhaust heat loss; at the same time, it will also increase the power consumption of the induced draft fan. Based on this, a boiler flue gas hot air drying device for drying combustion raw materials is proposed to solve the above problems. Summary of the invention

[0003] The purpose of the present invention is to solve the problems existing in the prior art and to propose a boiler flue gas hot air drying device for drying combustion raw materials.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A boiler flue gas hot air drying device for drying combustion raw materials, comprising a hot air drying tank body, wherein a crushing air mixing and feeding unit, a hot air feeding and drying unit and a flue gas waste heat utilization unit are arranged in the hot air drying tank body;

[0006] An assembly base for installing a flue gas waste heat utilization unit is provided at the bottom of the hot air drying tank body. The flue gas waste heat utilization unit includes a flue gas delivery pipeline for delivering boiler flue gas. A gas dispersion hood is provided at the end of the flue gas delivery pipeline. The gas dispersion hood is connected to the assembly base through a plurality of equally distributed pipes. A fresh air supply pipe is provided inside the flue gas delivery pipeline.

[0007] The hot air feeding and drying unit comprises a plurality of vertical air delivery pipes evenly distributed on an assembly base, the side walls of the vertical air delivery pipes are provided with biomass feeding pipes, the inner wall of the hot air drying tank body is rotatably connected with a switching feed tray, a plurality of inclined filtering and storage slots are provided inside the switching feed tray, and an inclined feed pipe adapted to the filtering and storage slots is provided on the top of the vertical air delivery pipe;

[0008] A support frame is provided on the top of the hot air drying tank, a driving motor is provided on the support frame, a filter blocking net is provided at the bottom of the support frame, and a smoke exhaust pipe is provided on the top of the support frame;

[0009] The crushing wind mixing feeding unit includes a cutting and crushing seat and a rotating crushing table arranged in the hot air drying tank body, a storage seat is arranged at the bottom of the hot air drying tank body, a horizontal wind mixing pipe connected to the fresh air supply pipe is arranged in the storage seat, and a feeding port connected to the horizontal wind mixing pipe is opened at the bottom of the storage seat.

[0010] Preferably, one end of the fresh air supply pipe passes through the smoke conveying pipe to extend outward and is connected to an air supply pump, and the other end of the fresh air supply pipe passes through the smoke conveying pipe through a turning elbow to extend upward and is connected to the horizontal air mixing pipe.

[0011] Preferably, the assembly base is provided with a plurality of connecting pipe openings connected to the equalizing pipe, and a conical air supply filter cover is fixedly connected to the top of the connecting pipe opening for blocking and filtering impurities in the biomass fuel, and the vertical air supply pipe is sleeved on the assembly base at the connecting pipe opening.

[0012] Preferably, a plurality of fan-shaped support members are fixedly connected to the inner wall of the hot air drying tank body, a connecting port is provided on the fan-shaped support member, the inclined feed pipe extends inward through the side wall of the hot air drying tank body and is adapted to be connected with the connecting port, and the switching feed tray fits tightly on the fan-shaped support member.

[0013] Preferably, a vertical drive shaft is provided on the support frame, the output end of the drive motor is connected to the vertical drive shaft through a worm gear transmission, a support ring is fixedly provided at the bottom of the fan-shaped support member, the support ring is rotatably connected to the rotary crushing table through a lower bearing, and the end of the vertical drive shaft extends downward and is fixedly connected to the rotary crushing table.

[0014] Preferably, a driving inner gear ring is fixedly provided at the bottom of the switching feed tray, and the driving inner gear ring is rotatably connected to the inner wall of the support ring through an external bearing.

[0015] Preferably, a central gear is fixedly connected to the outer side wall of the vertical drive shaft, and the central gear is meshedly connected with the driving inner gear ring through a plurality of planetary gears. A rotating shaft connector for supporting the planetary gears is arranged inside the support ring.

[0016] Preferably, the inner side wall of the cutting and crushing seat and the inner wall of the rotating crushing table are both provided with a rolling serrated layer.

[0017] Preferably, a material flow valve for controlling the biomass fuel delivery rate is provided in the feed port.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. The present invention is designed for boilers, and the biomass fuel is dried by the flue gas generated by the boiler, and the biomass fuel is transported by the flue gas in a vertical air delivery pipe. The heat in the boiler flue gas is used to heat the biomass fuel during transportation, and the moisture in the biomass fuel is taken away by the flue gas during the heating process. By designing the weight of the biomass fuel and the lift of the flue gas, it is ensured that only the fully dried biomass fuel can be transported to the filtering and storing slot, thereby ensuring the dryness of the boiler combustion raw materials and ensuring the boiler combustion quality.

[0020] 2. The present invention realizes the timed delivery of the biomass fuel set in the filter storage slot of the switching feed tray to the crushing air mixed feeding unit by switching the rotation of the feed tray, realizes the feeding and drying cycle operation, and ensures the transportation effect of the flue gas on the biomass fuel.

[0021] 3. The present invention crushes the dried biomass fuel through a crushing air mixing and feeding unit, mixes it with the preheated air in the horizontal air mixing tube, and transports it to the boiler combustion chamber for combustion, thereby ensuring the effective mixing of biomass fuel and air during combustion and ensuring the full combustion of biomass fuel. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the main assembly structure of a boiler flue gas hot air drying device for drying combustion raw materials proposed by the present invention;

[0023] Figure 2 This is a schematic diagram of the expanded structure of a boiler flue gas hot air drying device for drying combustion raw materials proposed by the present invention;

[0024] Figure 3 This is a schematic diagram of the three-dimensional structure of a boiler flue gas hot air drying device for drying combustion raw materials proposed by the present invention;

[0025] Figure 4 This is a schematic diagram of the structure assembly inside the hot air drying tank in a boiler flue gas hot air drying device for drying combustion raw materials proposed by the present invention;

[0026] Figure 5 This is a schematic diagram of the connection relationship structure of the support ring in a boiler flue gas hot air drying device for drying combustion raw materials proposed by the present invention;

[0027] Figure 6 It is a schematic diagram of a partial structural cross-section of a hot air drying tank in a boiler flue gas hot air drying device for drying combustion raw materials proposed by the present invention;

[0028] Figure 7This is a schematic structural diagram of a flue gas waste heat utilization unit in a boiler flue gas hot air drying device for drying combustion raw materials proposed by the present invention.

[0029] In the figure: 1. hot air drying tank; 2. assembly base; 3. flue gas conveying pipeline; 4. gas dispersion hood; 5. equalizing pipe; 6. fresh air supply pipe; 7. vertical air delivery pipe; 8. biomass feed pipe; 9. switch feed tray; 10. filter storage slot; 11. inclined feed pipe; 12. support frame; 13. drive motor; 14. filter blocking net; 15. flue gas exhaust suction pipe; 16. cutting and crushing seat; 17. rotary crushing table; 18. storage seat; 19. horizontal air mixing pipe; 20. feed port; 21. air supply pump; 22. connecting pipe port; 23. conical air supply filter cover; 24. fan-shaped support; 25. vertical drive shaft; 26. worm gear transmission; 27. support ring; 28. driving inner gear ring; 29. ​​central gear; 30. planetary gear; 31. shaft connector; 32. rolling sawtooth layer. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0031] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "mounted / connected", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] Example, see Figure 1 - Figure 7 , a boiler flue gas hot air drying device for drying combustion raw materials, comprising a hot air drying tank body 1, in which a crushing air mixing feeding unit, a hot air feeding drying unit and a flue gas waste heat utilization unit are arranged;

[0033] An assembly base 2 for installing a flue gas waste heat utilization unit is provided at the bottom of the hot air drying tank body 1. The hot air drying tank body 1 is arranged on the assembly base 2. The assembly base 2 realizes the support of the hot air drying tank body 1. The flue gas waste heat utilization unit includes a flue gas conveying pipeline 3 for conveying boiler flue gas. The flue gas conveying pipeline 3 is an existing boiler flue gas conveying system. A gas dispersion hood 4 is provided at the end of the flue gas conveying pipeline 3. The gas dispersion hood 4 is connected to the assembly base 2 through a plurality of equal distribution pipes 5. A fresh air supply pipe 6 is provided inside the flue gas conveying pipeline 3.

[0034] Among them, the fresh air supply pipe 6 is located inside the flue gas conveying pipe 3 and is made of metal material with good thermal conductivity. The fresh air supply pipe 6 can be heated by the hot air in the flue gas conveying pipe 3 during the conveying process, and can meet the requirements of rapid and effective combustion when it is mixed with biomass fuel in the later stage and transported to the boiler for combustion.

[0035] Furthermore, one end of the fresh air supply pipe 6 extends outward through the smoke conveying pipe 3 and is connected to an air supply pump 21. The air supply pump 21 is a prior art and will not be described in detail here. It achieves the effect of pressurized delivery of external air. The other end of the fresh air supply pipe 6 extends upward through the smoke conveying pipe 3 through a turning elbow and is connected to the horizontal air mixing pipe 19.

[0036] The hot air feeding and drying unit includes a plurality of vertical air delivery pipes 7 evenly distributed on the assembly base 2, and a biomass feeding pipe 8 is arranged on the side wall of the vertical air delivery pipe 7, and the biomass feeding pipe 8 feeds biomass fuel with a certain weight specification after preliminary processing and cutting;

[0037] When the switch feed tray 9 is rotated so that the filter storage slot 10 is misaligned with the inclined feed pipe 11, the upper part of the inclined feed pipe 11 will be blocked, and the flow of smoke inside it will be blocked. At this time, the biomass feed pipe 8 is used to feed inward;

[0038] The biomass fuel transported by the flue gas will absorb the heat of the flue gas during the transportation process. The heat generated will dry the biomass fuel, and the moisture will be carried away by the flue gas. By controlling the size of the airflow, the biomass fuel that has been heated and dried by the flue gas can be transported to the filter storage slot 10 by the conveying force generated by the flue gas. The relatively moist biomass fuel will be continuously dried until the dry weight is met and then it will be transported to the filter storage slot 10 to achieve transfer.

[0039] Furthermore, the assembly base 2 is provided with a plurality of connecting pipe openings 22 connected to the equalizing pipe 5, and a conical air supply filter cover 23 is fixedly connected to the top of the connecting pipe opening 22 for blocking and filtering the impurities of the biomass fuel, and the vertical air supply pipe 7 is sleeved on the assembly base 2 at the connecting pipe opening 22;

[0040] A further advantage of adopting the above method is that some foreign matter such as stones and metal impurities in the biomass fuel transported by flue gas cannot be transported upward by the lift generated by the flue gas, and the foreign matter will fall downward under the action of gravity. The conical air supply filter cover 23 can ensure that the foreign matter falls around the connecting pipe port 22, which is convenient for regular cleaning of impurities during later maintenance, and prevents the biomass fuel containing impurities from entering the hot air drying tank body 1, causing blockage and damage to components.

[0041] The inner wall of the hot air drying tank 1 is rotatably connected with a switching feed tray 9, and a plurality of inclined filtering and storing slots 10 are provided inside the switching feed tray 9. An inclined feed pipe 11 adapted to the filtering and storing slots 10 is provided on the top of the vertical air delivery pipe 7;

[0042] It is worth noting that when the filter storage slot 10 is misaligned with the inclined feed pipe 11, the outer wall of the switch feed tray 9 will seal the end of the inclined feed pipe 11, thereby stopping the internal gas output.

[0043] Furthermore, a plurality of fan-shaped support members 24 are fixedly connected to the inner wall of the hot air drying tank body 1, and a connection port is opened on the fan-shaped support member 24. The inclined feed pipe 11 passes through the side wall of the hot air drying tank body 1 and extends inward, and is adapted to be connected with the connection port, and the switching feed tray 9 is closely attached to the fan-shaped support member 24;

[0044] The fan-shaped support members 24 support the inclined feed pipe 11 to ensure its stability, wherein there is a certain distance between adjacent fan-shaped support members 24 to ensure that after the feed tray 9 is switched, the dried biomass fuel delivered to the filter storage slot 10 is delivered to the hot air drying tank 1 at the gap between the fan-shaped support members 24.

[0045] A support frame 12 is arranged on the top of the hot air drying tank 1, and a driving motor 13 is arranged on the support frame 12. The driving motor 13 is arranged horizontally so as not to affect the filtering effect of the filtering barrier net 14. A filtering barrier net 14 is arranged at the bottom of the support frame 12, and a smoke exhaust pipe 15 is arranged on the top of the support frame 12. The smoke exhaust pipe 15 is externally connected to a negative pressure pump to generate suction force on the filtering barrier net 14 to ensure the conveying effect of the smoke;

[0046] The mesh size of the filter barrier 14 should meet the filtering effect on the biomass fuel being transported, and can filter some biomass ash in the flue gas, so that the biomass ash can re-enter the boiler together with the biomass fuel, reduce the ash content in the flue gas, and reduce the difficulty of subsequent processing.

[0047] The crushing air mixing feeding unit includes a cutting and crushing seat 16 and a rotating crushing table 17 arranged in the hot air drying tank body 1. The inner wall of the cutting and crushing seat 16 and the inner wall of the rotating crushing table 17 are both provided with a rolling sawtooth layer 32. The dried biomass fuel will enter between the cutting and crushing seat 16 and the rotating crushing table 17. The dried biomass fuel can be easily broken into smaller pieces when under pressure, thereby facilitating the subsequent uniform transportation of the biomass fuel through the horizontal air mixing pipe 19.

[0048] A material storage seat 18 is provided at the bottom of the hot air drying tank body 1, and a horizontal air mixing pipe 19 connected to the fresh air supply pipe 6 is provided in the material storage seat 18. A material delivery port 20 connected to the horizontal air mixing pipe 19 is opened at the bottom of the material storage seat 18. A material flow valve for controlling the biomass fuel delivery rate is provided in the material delivery port 20. The material flow valve is a prior art and will not be described in detail here. It controls the delivery amount of the biomass fuel.

[0049] Furthermore, a vertical drive shaft 25 is provided on the support frame 12, and the output end of the drive motor 13 is connected to the vertical drive shaft 25 through a worm gear transmission 26. A support ring 27 is fixedly provided at the bottom of the fan-shaped support member 24, and the support ring 27 is rotatably connected to the rotating crushing table 17 through a lower bearing. The end of the vertical drive shaft 25 extends downward and is fixedly connected to the rotating crushing table 17.

[0050] Furthermore, a driving inner gear ring 28 is fixedly provided at the bottom of the switching feed tray 9, and the driving inner gear ring 28 is rotatably connected to the inner wall of the support ring 27 through an external bearing. A center gear 29 is fixedly connected to the outer wall of the vertical drive shaft 25, and the center gear 29 is meshed with the driving inner gear ring 28 through a plurality of planetary gears 30. A rotating shaft connector 31 is provided inside the support ring 27 for supporting the planetary gears 30.

[0051] It is worth noting that, by setting the planetary gear 30 and the central gear 29, it can ensure that the switching feed tray 9 connected to the driving inner gear ring 28 can rotate stably under the premise of changing the transmission ratio, thereby achieving high-speed rotation of the rotary crushing table 17 and slow rotation of the switching feed tray 9.

[0052] When the present invention is in operation, the flue gas generated after the boiler is burned will be transported through the flue gas delivery pipe 3, and the fresh air supply pipe 6 in the flue gas delivery pipe 3 will use the high temperature of the flue gas to heat the air in the fresh air supply pipe 6, and the heated air will be transported to the horizontal air mixing pipe 19 to mix with the dried biomass fuel, and then transported to the boiler for combustion;

[0053] The continuously transported flue gas will be dispersed to the equalizing pipe 5 through the gas dispersion cover 4, and transported to the flue gas conveying pipe 3 on the outer wall of the hot air drying tank 1. The flue gas is transported upward from the conical air supply filter cover 23, and the biomass fuel transported through the biomass feeding pipe 8 is driven to be transported under the action of the airflow lift of the flue gas;

[0054] During the transportation process, the biomass fuel transported by the flue gas will absorb the heat of the flue gas during the transportation process, and the generated heat will realize the drying of the biomass fuel. The moisture will be carried away by the flue gas and discharged outward through the flue gas exhaust suction pipe 15 for subsequent flue gas treatment to ensure that the biomass fuel is fully dried. The biomass fuel that meets the dry state will be transported by the flue gas to the filter storage slot 10. Due to the obstruction of the filter blocking net 14, the biomass fuel will be concentrated in the filter storage slot 10. At this time, the switching feed tray 9 under the action of the driving motor 13 will be driven to rotate, so that the filter storage slot 10 and the inclined feed pipe 11 are misaligned. The biomass fuel that loses the airflow lift will fall to the crushing wind mixed feeding unit under the action of gravity;

[0055] The rotating crushing table 17 under the action of the driving motor 13 will cut and crush the biomass fuel in the cutting and crushing seat 16. The dried biomass fuel can be easily broken into smaller pieces when under pressure. The crushed biomass fuel will eventually be mixed with the preheated air in the horizontal air mixing pipe 19 and transported to the boiler combustion chamber for combustion, thereby ensuring the combustion quality of the biomass fuel.

[0056] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A boiler flue gas hot air drying device for drying combustion raw materials, comprising a hot air drying tank (1), characterized in that: The hot air drying tank (1) is provided with a crushing air mixing and feeding unit, a hot air feeding and drying unit and a flue gas waste heat utilization unit; An assembly base (2) for installing a flue gas waste heat utilization unit is arranged at the bottom of the hot air drying tank (1); the flue gas waste heat utilization unit comprises a flue gas conveying pipeline (3) for conveying boiler flue gas; a gas dispersion hood (4) is arranged at the end of the flue gas conveying pipeline (3); the gas dispersion hood (4) is connected to the assembly base (2) via a plurality of equalizing pipes (5); a fresh air supply pipe (6) is arranged inside the flue gas conveying pipeline (3); The hot air feeding and drying unit comprises a plurality of vertical air delivery pipes (7) evenly distributed on an assembly base (2), a biomass feeding pipe (8) being arranged on the side wall of the vertical air delivery pipe (7), a switching feed tray (9) being rotatably connected to the inner wall of the hot air drying tank body (1), a plurality of inclined filtering and storage slots (10) being arranged inside the switching feed tray (9), and an inclined feed pipe (11) being matched with the filtering and storage slots (10) being arranged on the top of the vertical air delivery pipe (7); A support frame (12) is arranged on the top of the hot air drying tank body (1), a driving motor (13) is arranged on the support frame (12), a filter blocking net (14) is arranged at the bottom of the support frame (12), and a smoke exhaust pipe (15) is arranged on the top of the support frame (12); The crushing air mixing feeding unit comprises a cutting and crushing seat (16) and a rotating crushing table (17) arranged in a hot air drying tank body (1); a material storage seat (18) is arranged at the bottom of the hot air drying tank body (1); a horizontal air mixing pipe (19) connected to a fresh air supply pipe (6) is arranged in the material storage seat (18); and a material feeding port (20) connected to the horizontal air mixing pipe (19) is opened at the bottom of the material storage seat (18); A plurality of fan-shaped support members (24) are fixedly connected to the inner wall of the hot air drying tank body (1), and a connecting port is provided on the fan-shaped support member (24). The inclined feed pipe (11) passes through the side wall of the hot air drying tank body (1) and extends inwardly, and is adapted to be connected with the connecting port. The switching feed tray (9) is tightly fitted on the fan-shaped support member (24); There is a certain distance between adjacent fan-shaped support members (24), so that after the feed tray (9) is switched to be misaligned, the dried biomass fuel delivered to the filter storage slot (10) is delivered to the hot air drying tank (1) at the gap between the fan-shaped support members (24); A vertical drive shaft (25) is arranged on the support frame (12); an output end of the drive motor (13) is connected to the vertical drive shaft (25) via a worm gear transmission member (26); a support ring (27) is fixedly arranged at the bottom of the fan-shaped support member (24); the support ring (27) is rotatably connected to the rotary crushing table (17) via a lower bearing; an end of the vertical drive shaft (25) extends downward and is fixedly connected to the rotary crushing table (17); A driving inner gear ring (28) is fixedly provided at the bottom of the switching feed tray (9), and the driving inner gear ring (28) is rotatably connected to the inner wall of the support ring (27) via an external bearing; A central gear (29) is fixedly connected to the outer wall of the vertical drive shaft (25); the central gear (29) is meshedly connected to the driving inner gear ring (28) via a plurality of planetary gears (30); and a rotating shaft connecting member (31) for supporting the planetary gears (30) is provided inside the support ring (27); The inner wall of the cutting and crushing seat (16) and the inner wall of the rotating crushing table (17) are both provided with a rolling sawtooth layer (32), and the dried biomass fuel will enter between the cutting and crushing seat (16) and the rotating crushing table (17).

2. A boiler flue gas hot air drying device for drying combustion raw materials according to claim 1, characterized in that: One end of the fresh air supply pipe (6) penetrates the smoke conveying pipe (3) to extend outwards and is connected to an air supply pump (21); the other end of the fresh air supply pipe (6) penetrates the smoke conveying pipe (3) through a turning elbow to extend upwards and is connected to a horizontal air mixing pipe (19).

3. A boiler flue gas hot air drying device for drying combustion raw materials according to claim 1, characterized in that: The assembly base (2) is provided with a plurality of connecting pipe openings (22) connected to the equalizing pipe (5); the top of the connecting pipe opening (22) is fixedly connected with a conical air supply filter cover (23) for blocking and filtering impurities in the biomass fuel; the vertical air supply pipe (7) is sleeved on the assembly base (2) at the connecting pipe opening (22).

4. The boiler flue gas hot air drying device for drying combustion raw materials according to claim 1, characterized in that: A material flow valve for controlling the biomass fuel delivery rate is arranged in the feed port (20).

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