A hot air supply device for a grain drying tower

Abstract

The utility model belongs to hot -blast production device especially a kind of hot -blast supply device for grain drying tower, including combustion furnace, ash removal heat exchange device, air mixing chamber and induced draft fan connected in turn;Ash removal heat exchange device includes box and ash removal device in box, and the air inlet and air outlet pipe are respectively set in the both ends of box, air inlet is communicated with external air, air outlet pipe is communicated to air mixing chamber import, ash removal device includes smoke inlet pipe, ash removal equipment and smoke outlet pipe, the outer diameter of smoke inlet pipe is less than the inner diameter of air inlet and extends air inlet connection to combustion furnace, the outer diameter of smoke outlet pipe is less than the inner diameter of air outlet pipe and extends air outlet pipe communication to air mixing chamber, and air mixing chamber outlet pipeline is connected to induced draft fan import.The utility model separates through ash removal device to separate the soot impurity in flue gas, and flue gas exchanges heat with the air in box through ash removal device, and finally treated flue gas is mixed with heated air for grain drying, ensure that heat energy is fully utilized, reduce combustion furnace fuel consumption.

Description

Technical Field

[0001] This utility model pertains to hot air production devices, and more particularly to a hot air supply device for a grain drying tower. Background Technology

[0002] Hot air furnaces are important supporting equipment for grain drying towers, used to produce a large amount of high-temperature hot air for the grain drying tower. In the existing technology, the flue gas discharged from the air heat exchanger of the hot air furnace used for grain towers is directly discharged into the atmosphere, resulting in heat waste. If the flue gas is simply treated and then used for grain drying, there is a risk of pipe blockage, which will affect production. Summary of the Invention

[0003] This invention addresses the problem of heat waste in existing hot air furnaces for grain drying towers, where the heated gas is used as hot air for grain drying after being heated by a heat exchanger, while the flue gas is directly treated and discharged. The invention provides a hot air supply device for grain drying towers that separates ash and impurities from the flue gas using an ash removal device. Simultaneously, the flue gas exchanges heat with the air inside the furnace through the ash removal device. Finally, the treated flue gas is mixed with the heated air for grain drying, ensuring full utilization of heat energy and reducing fuel consumption in the combustion furnace.

[0004] To achieve the above objectives, the technical solution of this utility model is as follows: A hot air supply device for a grain drying tower includes a combustion furnace, an ash removal and heat exchange device, a mixing chamber, and an induced draft fan connected in sequence. The ash removal and heat exchange device includes a housing and an ash removal device disposed within the housing. The ash removal device is used to remove impurities from the flue gas discharged from the combustion furnace. An air inlet and an air outlet are respectively opened at both ends of the housing. The air inlet is connected to the outside air, and the air outlet is connected to the inlet of the mixing chamber. The ash removal device includes a flue pipe, an ash removal device, and a flue pipe. The outer diameter of the flue pipe is smaller than the inner diameter of the air inlet and extends out of the air inlet to connect to the combustion furnace. The outer diameter of the flue pipe is smaller than the inner diameter of the air outlet and extends out of the air outlet to connect to the mixing chamber. The outlet pipe of the mixing chamber is connected to the inlet of the induced draft fan. The flue gas is treated by dust separation through the ash removal device and exchanges heat with the air inside the housing. The two are then mixed in the mixing chamber and used for grain drying.

[0005] Preferably, the ash removal device further includes a flue pipe, a cyclone separator, an exhaust pipe, and multiple ash removal boxes arranged in sequence. The flue pipe is connected to the upper inlet of one of the ash removal boxes, and the upper ends of two adjacent ash removal boxes are connected by the flue pipe. Each ash removal box is fixedly equipped with a partition, with the two sides of the partition facing the inlet and outlet of the ash removal box, respectively. The partition is fixedly connected to the inner wall of the ash removal box, and there is a gap between the lower end of the partition and the bottom surface of the ash removal box. The outlet pipe at the upper end of the ash removal box away from the flue pipe is connected to the inlet of the cyclone separator. The upper outlet of the cyclone separator is connected to the flue pipe through the exhaust pipe. The ash removal box reduces the flue gas velocity and extends its travel, so that the dust contained therein is separated from the gas. The dust in the cyclone separator is further separated by the cyclone separator.

[0006] Preferably, the air inlet of the housing is provided with multiple air inlets, and each air inlet is equipped with a valve to adjust the air intake volume. The multiple air inlets ensure the air intake volume.

[0007] Preferably, an ash discharge pipe is provided on one side of the lower end of the ash removal box. The ash discharge pipe extends out of the box body and is covered with a cap. The ash discharge pipe is blocked by the cap of the working chamber and is opened periodically to clean the dust inside the ash removal box.

[0008] Preferably, the lower ash discharge port of the cyclone separator is connected to an auger, and the outlet end of the auger extends out of the housing, discharging the solid impurities separated by the cyclone separator through the auger support.

[0009] Preferably, the lower part of the ash removal box is fixedly connected to the bottom surface of the box body by a support rod, and there are gaps between the side plates of the ash removal box and the side walls of the box body to ensure full contact between the outside of the ash removal box and the air entering the box body, thereby ensuring the heating of the air.

[0010] Preferably, each of the ash removal boxes is provided with a vent pipe running through it along the airflow direction. The vent pipe passes through the corresponding partition to ensure the airflow into the box and to increase the heat exchange area between the box and the flue gas, thereby ensuring the heating effect.

[0011] Preferably, the air outlet duct wall is provided with an adjustment valve for adjusting the gas flow rate in the air outlet duct. By adjusting the valve, the air velocity in the box is adjusted, thereby adjusting its temperature.

[0012] Preferably, the flue gas inlet pipe extends out of the housing and has at least two circumferentially evenly distributed oxygen inlets. Oxygen is supplied to the flue gas inlet pipe through the oxygen inlets, so that the dust in the flue gas entering the dust removal box is fully burned.

[0013] The beneficial effects of this utility model through the above technical solution are as follows: 1. This utility model incorporates an ash removal device within the chamber. During the process of removing dust from the flue gas, the ash removal device heats the air inside the chamber. The final treated flue gas is mixed with the heated air for grain drying, thereby achieving complete collection and utilization of combustion heat and external cooling heat. This reduces heat loss caused by medium exchange, resulting in high fuel utilization and low heat loss. Practical application has verified that it saves 85-90% of fuel costs compared to natural gas and approximately 65% ​​compared to coal.

[0014] 2. This utility model adopts an air cooling and temperature reduction design for flue gas and supplements oxygen to assist combustion and eliminate smoke. By using oxygen to assist combustion, it ensures that the unburned impurities contained in the flue gas are fully burned, avoiding the existence of sparks and other safety hazards.

[0015] 3. This utility model uses multiple dust removal boxes and a cyclone separator to treat flue gas for dust removal. On the one hand, the flue gas enters the dust removal box from the inlet pipe or flue pipe under the action of the induced draft fan. It impacts the baffle plate, and the dust falls down. The gas velocity decreases significantly due to the sudden increase in the cross-sectional area of ​​the area it flows through (and the heat exchange and cooling with the outside air). It gradually moves downward. The baffle plate extends the path of the flue gas in the dust removal box. The oxygen transported to the inlet pipe comes into full contact with the flue gas in the dust removal box, so that the substances in the flue gas are fully combusted. After passing through multiple dust removal boxes, the residual smoke is further combusted and gasified. On the other hand, the non-combustible dust and other impurities are separated. Then the flue gas enters the cyclone separator to further separate the solid dust and other substances, ensuring the gas-dust separation effect. Finally, the residual gas is transported to the outlet pipe, achieving clean dust removal and no odor.

[0016] 4. This utility model utilizes the action of an induced draft fan. Air first enters the housing through the air inlet and multiple induced draft inlets, then fully contacts the ash removal box through the gap between the ash removal box and the inner wall of the housing or through the ventilation pipe. After passing through the flue pipe, cyclone separator, and exhaust pipe, the air is discharged into the mixing chamber through the exhaust pipe. The air fully contacts the ash removal device, which cools the flue gas passing through the ash removal device on the one hand, and heats itself on the other hand.

[0017] 5. After the flue gas treated by dust removal and ash removal is mixed with the heated air in the mixing chamber, it is transported to the grain drying tower by the action of the induced draft fan to dry the grain. The flow rate of the heated air is controlled by controlling the opening and closing of some valves and adjusting the opening of the regulating valve. Since the temperature of the treated flue gas is still higher than that of the heated air, the temperature of the gas mixed in the mixing chamber can be regulated by controlling the flow rate of the heated air. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the present invention. Figure 1 .

[0019] Figure 2 This is a schematic diagram of the structure of the present invention. Figure 2 .

[0020] Figure 3 This is a schematic diagram of the structure of the present invention. Figure 3 .

[0021] Figure 4 This is a schematic diagram of the structure of the present invention. Figure 4 .

[0022] Figure 5 This is a schematic diagram of the ash removal device of this utility model.

[0023] Figure 6 This is a schematic diagram of the structure of the regulating valve of this utility model during installation.

[0024] The attached diagram is labeled as follows: 1 is the housing, 11 is the air inlet, 12 is the air outlet, 13 is the exhaust inlet, 14 is the ventilation pipe, and 15 is the regulating valve. 21 is the smoke inlet pipe, 22 is the smoke outlet pipe, 23 is the smoke pipe, 24 is a cyclone separator, 25 is the exhaust pipe, 26 is the ash removal box, 27 is the partition, 28 is the ash outlet pipe, 29 is the cover, and 210 is the auger. Detailed Implementation

[0025] The present invention will be further described below with reference to the accompanying drawings and specific embodiments: like Figures 1-6 As shown, this embodiment provides a hot air supply device for a grain drying tower, including a combustion furnace, an ash removal and heat exchange device, a mixing chamber, and an induced draft fan connected in sequence. The heat generated by fuel combustion in the combustion furnace and the flue gas enter the ash removal and heat exchange device. The ash removal and heat exchange device removes soot and dust from the flue gas and heats the air at the same time. Then, the treated flue gas and heated air are mixed in the mixing chamber and then transported to the grain drying tower by the induced draft fan for drying operations.

[0026] The ash removal and heat exchange device includes a housing 1 and an ash removal device installed inside the housing. The ash removal device is used to remove impurities from the flue gas discharged from the combustion furnace. An air inlet 11 and an air outlet 12 are respectively opened at both ends of the housing 1. The air inlet 11 is connected to the outside air, and the air outlet 12 is connected to the inlet of the mixing chamber. Air enters the housing 1 from the air inlet 11, is heated, and then enters the mixing chamber from the air outlet 12. The ash removal device includes a flue gas inlet 21, ash removal equipment, and a flue gas outlet 22. The outer diameter of the flue gas inlet 21 is smaller than the inner diameter of the air inlet 11 and extends beyond the air inlet. The outlet 11 is connected to the combustion furnace. The outer diameter of the flue gas pipe 22 is smaller than the inner diameter of the air outlet pipe 12 and extends out of the air outlet pipe 12 to connect to the mixing chamber. The outlet pipe of the mixing chamber is connected to the inlet of the induced draft fan. The heat generated by the combustion furnace and the flue gas enter the ash removal equipment through the flue gas pipe 21. When the air enters the housing 1 through the air inlet 11, it directly contacts the flue gas pipe 21 to achieve heating. When the air exits the housing 1 from the air outlet pipe 12 and enters the mixing chamber, it surrounds the flue gas pipe 22 and further exchanges heat with the flue gas in the flue gas pipe 22 to achieve self-heating.

[0027] The ash removal device also includes a flue pipe 23, a cyclone separator 24, an exhaust pipe 25, and multiple ash removal boxes 26 arranged sequentially. The flue pipe 21 is connected to the upper inlet of one of the ash removal boxes 26. After the flue pipe 21 extends out of the box body 1, it has at least two circumferentially evenly distributed oxygen inlets. The heat generated by the combustion furnace and the oxygen transported by the flue gas through the flue pipe 21 enter the corresponding ash removal box 26. The upper ends of two adjacent ash removal boxes 26 are connected by the flue pipe 23. After passing through multiple ash removal boxes 26, the flue gas comes into full contact with the oxygen, achieving complete combustion of residual smoke. On the other hand, each ash removal box 26 is fixedly equipped with a partition 27. The two sides of the partition 27 are respectively facing the inlet and outlet of the ash removal box 26. The partition 27 is fixedly connected to the inner wall of the ash removal box 26, and there is a gap between the lower end of the partition 27 and the inner bottom surface of the ash removal box 26. After the flue gas enters the ash removal box 26, it impacts the partition 27, and then due to the expansion of the cross-sectional area, it is further irritated. The flue gas flows slowly downwards, passing through the gap below the baffle 27 before flowing upwards until it exits from the outlet of the ash removal box 26. During this process, it is cooled by heat exchange with the outside air in the ash removal box 26. The flue gas impacts the baffle 27, reduces the flue gas velocity, extends the flue gas path, and fully mixes and contacts oxygen for combustion. On the one hand, this ensures full gasification, and on the other hand, the gas in the flue gas is separated from solid impurities such as dust. The outlet pipe at the upper end of the ash removal box 26, which is away from the inlet pipe 21, is connected to the inlet of the cyclone separator 24. The upper outlet of the cyclone separator 24 is connected to the exhaust pipe 22 through the exhaust pipe 25. Then the flue gas enters the cyclone separator 24, where the fully combusted flue gas undergoes further gas-dust separation to ensure the quality of the discharged gas. Finally, after the flue gas is fully combusted, gasified, and ash and dust removed, the residual gas enters the mixing chamber through the exhaust pipe 22 and mixes with the heated air to become hot air for grain drying.

[0028] The air inlet of the housing 1 is provided with multiple air inlets 13, each equipped with a valve. The air outlet 12 is provided with a regulating valve 15 on its wall to regulate the gas flow rate inside the air outlet 12. Since the temperature of the treated flue gas discharged into the mixing chamber from the flue 22 is higher than the temperature of the heated air discharged from the housing 1, the air flow rate entering and leaving the housing 1 is controlled by the valves and the regulating valve 15 to regulate the temperature of the hot air mixed in the mixing chamber.

[0029] As one possible implementation method, such as Figure 6 As shown, the regulating valve 15 is a plate that slides up and down on the wall of the air outlet pipe 12. The lower end of the plate has a groove (making the regulating valve 15 a U-shaped plate structure). The bottom of the groove matches the upper part of the smoke outlet pipe 22. By sliding the regulating valve 15 up and down, the degree of sealing of the annular gap between the inner wall of the air outlet pipe 12 and the outer wall of the smoke outlet pipe 22 can be adjusted. Specifically, the flow rate of air through the air outlet pipe 12 can be adjusted.

[0030] The ash removal box 26 has an ash discharge pipe 28 on one side of its lower end. The ash discharge pipe 28 extends out of the box body 1 and is equipped with a cover 29. After a period of use, the cover 29 is opened periodically to clean the inside of the ash removal box 26 so that the dust and other impurities separated therein can be discharged from the ash discharge pipe 28.

[0031] The lower ash discharge port of the cyclone 24 is connected to an auger 210, the outlet end of which extends out of the housing 1. The auger 210 is used to discharge solid dust and impurities from the flue gas separated by the cyclone 24.

[0032] The lower part of the ash removal box 26 is fixedly connected to the inner bottom surface of the box body 1 by a support rod. There is a gap between the side plate of the ash removal box 26 and the side wall of the box body 1. Each ash removal box 26 has a vent pipe 14 running through it along the air intake direction. The vent pipe 14 passes through the corresponding partition 27. The gap and the vent pipe 14 ensure that the air entering the box body 1 flows smoothly towards the air outlet pipe 12, and ensure that the air and the flue gas in the ash removal box 26 have sufficient heat exchange contact.

[0033] When in use, the induced draft fan is turned on. Under the action of the induced draft fan, the heat and flue gas generated in the combustion furnace enter the flue gas inlet pipe 21 and are treated by the ash removal device. Then, they enter the mixing chamber through the flue gas outlet pipe 22. Air enters the housing 1 from the air inlet 12 and the induced draft inlet 13. In the housing 1, heat is exchanged with the flue gas to achieve air heating. Then, the air enters the mixing chamber from the air outlet 12. Flue gas treatment process: Flue gas enters the inlet pipe 21, and oxygen is simultaneously supplied into the inlet pipe 21 through the oxygen inlet. The flue gas mixed with oxygen enters the ash removal chamber 26, impacts the baffle 27 in the ash removal chamber 26, and then passes through the flue on both sides and below the baffle 27 in the ash removal chamber 26. After passing through the flue pipe 23, it enters the next ash removal box 26. After being processed by multiple ash removal boxes 26 (the cross-section of the ash removal box 26 increases, the flow rate decreases, the stroke is longer, and it is in full contact with the inner wall of the ash removal box 26, thereby exchanging heat with the outside air and cooling, and making full contact with the oxygen mixed in there), the flue gas is fully combusted and the solid dust and impurities are separated. Then it enters the cyclone separator 24 for further separation of solid impurities. Finally, it enters the mixing chamber through the exhaust pipe 25 and the flue gas outlet pipe 22. Air heating process: Air enters the housing 1 through the air inlet 11 and multiple air inlets 13, then passes through the gap between multiple dust removal boxes 26 and the inner wall of the housing 1 and the ventilation pipe 14 to fully contact and exchange heat with them, and then after fully contacting and exchanging heat with the cyclone 24 and the exhaust pipe 25, it enters the mixing chamber through the air outlet 12. The flue gas treated in the mixing chamber is mixed with heated air and used as hot air for drying, which is then transported to the grain drying tower by an induced draft fan.

[0034] It should be noted that by controlling the number of valves opening and closing at multiple air inlets 13 and adjusting the opening of the valve 15, the flow rate of heated air is controlled, thereby achieving the regulation of the hot air temperature in the mixing chamber.

[0035] The embodiments described above are merely preferred embodiments of this utility model and are not intended to limit the scope of implementation of this utility model. Therefore, all equivalent changes or modifications made to the structure, features and principles described in the patent claims of this utility model should be included within the scope of the patent application of this utility model.

Claims

1. A hot air supply device for a grain drying tower, characterized in that, It includes a combustion furnace, an ash removal and heat exchange device, a mixing chamber and an induced draft fan connected in sequence; The ash removal heat exchange device includes a box (1) and an ash removal device installed inside the box. The ash removal device is used to remove impurities from the flue gas discharged from the combustion furnace. An air inlet (11) and an air outlet (12) are respectively opened at both ends of the box (1). The air inlet (11) is connected to the outside air, and the air outlet (12) is connected to the inlet of the mixing chamber. The ash removal device includes a flue pipe (21), an ash removal device and a flue pipe (22). The outer diameter of the flue pipe (21) is smaller than the inner diameter of the air inlet (11) and extends out of the air inlet (11) to connect to the combustion furnace. The outer diameter of the flue pipe (22) is smaller than the inner diameter of the air outlet pipe (12) and extends out of the air outlet pipe (12) to connect to the mixing chamber. The outlet pipe of the mixing chamber is connected to the inlet of the induced draft fan.

2. The hot air supply device for a grain drying tower according to claim 1, characterized in that, The ash removal device also includes a flue (23), a cyclone separator (24), an exhaust pipe (25), and a plurality of ash removal boxes (26) arranged in sequence. The flue (21) is connected to the upper inlet of one of the ash removal boxes (26). The upper ends of two adjacent ash removal boxes (26) are connected by the flue (23). Each ash removal box (26) is fixedly equipped with a partition (27). The two sides of the partition (27) are respectively facing the inlet and outlet of the ash removal box (26). The partition (27) is fixedly connected to the inner wall of the ash removal box (26), and there is a gap between the lower end and the bottom surface of the ash removal box (26). The outlet pipe at the upper end of the ash removal box (26) away from the flue (21) is connected to the inlet of the cyclone separator (24). The upper air outlet of the cyclone separator (24) is connected to the flue (22) through the exhaust pipe (25).

3. The hot air supply device for a grain drying tower according to claim 1, characterized in that, The air inlet of the box (1) is provided with multiple air inlets (13), and valves are provided on the air inlets (13).

4. The hot air supply device for a grain drying tower according to claim 2, characterized in that, The ash removal box (26) has an ash discharge pipe (28) on one side of its lower end. The ash discharge pipe (28) extends out of the box body (1) and is equipped with a cover (29).

5. A hot air supply device for a grain drying tower according to claim 2, characterized in that, The lower ash discharge port of the cyclone (24) is connected to an auger (210), and the outlet end of the auger (210) extends out of the housing (1).

6. A hot air supply device for a grain drying tower according to claim 2, characterized in that, The lower part of the ash removal box (26) is fixedly connected to the inner bottom surface of the box body (1) by a support rod, and there is a gap between the side plate of the ash removal box (26) and the side wall of the box body (1).

7. A hot air supply device for a grain drying tower according to claim 2, characterized in that, Each of the ash removal boxes (26) is provided with a ventilation pipe (14) running through it along the air intake direction, and the ventilation pipe (14) runs through the corresponding partition (27).

8. A hot air supply device for a grain drying tower according to claim 2, characterized in that, An adjustment valve (15) is provided on the wall of the air outlet pipe (12) to adjust the gas flow rate inside the air outlet pipe (12).

9. A hot air supply device for a grain drying tower according to claim 2, characterized in that, The smoke inlet pipe (21) extends out of the box body (1) and has at least two circumferentially evenly distributed oxygen inlets.

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