Gas hot blast stove with waste heat recovery function

Abstract

The utility model discloses a gas hot-blast stove with a waste heat recovery function, which relates to the technical field of gas hot-blast stoves and comprises a gas combustion furnace, an air heating cylinder is arranged on the outer side of the gas combustion furnace, and a hot air output pipe is fixed on the side wall of the air heating cylinder. According to the utility model, the smoke filter screen plate is embedded and inserted in the smoke exhaust pipe, and the smoke exhaust pipe and the connecting pipe are locked and fixed through the thread locking mechanism, so that the smoke exhaust pipe and the connecting pipe are in sealed butt joint, and the smoke filter screen plate is fixed and limited, so that the smoke filter screen plate can be conveniently disassembled and assembled; according to the air preheating device, the smoke filter screen plate is convenient to clean and replace, use is convenient, the preheating cover is fixed to the inner wall of the air preheating cylinder, high-temperature smoke generated in the fuel gas combustion process is guided into the preheating cover through the smoke exhaust pipe and the connecting pipe, and therefore the external cold air is preheated before being heated, and the heat exchange efficiency is improved. Therefore, the heating efficiency of the cold air is higher, and the effective recovery of the high-temperature flue gas waste heat in the gas combustion furnace is realized.

Description

Technical Field

[0001] This utility model relates to the field of gas-fired hot air furnace technology, and in particular to a gas-fired hot air furnace with waste heat recovery function. Background Technology

[0002] A gas-fired hot air furnace is a mechanical device that uses gas as its primary energy source. It is widely used in industries such as metallurgy, machinery, building materials, and chemicals. It generates heat by burning fuel and then transfers that heat to the air, raising its temperature. A gas-fired hot air furnace with waste heat recovery function is a highly efficient and energy-saving thermal energy device. It can recover some of the heat during combustion to preheat the combustion air or gas, thereby improving thermal efficiency and reducing fuel consumption.

[0003] For example, utility model patent application number 202420582127.8 discloses a hot air furnace with waste heat recovery function, including a hot air furnace body, a combustion exhaust chamber fixedly installed on the upper end face of the hot air furnace body, an exhaust fan fixedly installed on the left end face of the hot air furnace body, a connecting pipe connecting the exhaust fan and the combustion exhaust chamber, a smoke exhaust chamber connected to the upper side of the right end face of the connecting pipe, a hot air recovery pipe connected to the left end face of the exhaust fan, a first soot cleaning mechanism is provided inside the connecting pipe, and a second soot cleaning mechanism is provided inside the first soot cleaning mechanism.

[0004] Based on existing technologies, most hot air furnaces with waste heat recovery functions have fixed structures. The dust filter components in the high-temperature flue gas recovery process are generally fixed, making them inconvenient to disassemble, replace, and clean, resulting in poor usability. Furthermore, their waste heat recovery efficiency for high-temperature flue gas is not high, and the recovered waste heat is not easily applied directly to the gas-fired hot air furnace, failing to effectively improve the heating efficiency of cold air and thus lacking practicality. Therefore, this utility model proposes a gas-fired hot air furnace with waste heat recovery function to solve the problems existing in the prior art. Utility Model Content

[0005] To address the aforementioned problems, the purpose of this utility model is to propose a gas-fired hot air furnace with waste heat recovery function. This solves the problems that existing hot air furnaces with waste heat recovery function generally have fixed installation of flue gas filter components, which makes it inconvenient to disassemble, replace, and clean them, and the waste heat recovery efficiency of high-temperature flue gas is not high, making it inconvenient to directly apply the recovered waste heat to the gas-fired hot air furnace.

[0006] To achieve the purpose of this utility model, the utility model is implemented through the following technical solution: a gas-fired hot air furnace with waste heat recovery function, including a gas-fired combustion furnace, an air heating cylinder provided on the outside of the gas-fired combustion furnace, a hot air output pipe fixed on the side wall of the air heating cylinder, an open design at the end of the air heating cylinder away from the hot air output pipe, an air preheating cylinder fixed on the outer wall of the air heating cylinder, a cold air input pipe symmetrically fixed on the side of the air preheating cylinder near the hot air output pipe, exhaust pipes extending through to the outside of the air preheating cylinder fixed on both the front and rear side walls of the gas-fired combustion furnace, a connecting pipe sealed and connected at the end of the exhaust pipe away from the gas-fired combustion furnace by a threaded locking mechanism, a flue gas filter plate embedded and inserted inside the exhaust pipe near the connecting pipe, and a preheating cover communicating with the connecting pipe fixed on the inner wall of the air preheating cylinder.

[0007] Further improvements include: heat recovery rigid pipes connected to the preheating hood are fixed on both the front and rear side walls of the air preheating cylinder; heat recovery flexible pipes are connected between the heat recovery rigid pipes and the connecting pipes; and support rods are symmetrically fixed between the inner wall of the air preheating cylinder and the outer wall of the air heating cylinder.

[0008] A further improvement is that the threaded locking mechanism includes a threaded sleeve that is slidably sleeved on the outer wall of the connecting pipe and a limiting protrusion ring that is fixed on the outer wall of the connecting pipe. The inner wall of the threaded sleeve near the connecting pipe is provided with a limiting groove that matches the limiting protrusion ring. The outer wall of the exhaust pipe near the connecting pipe is provided with an external thread that matches the internal thread of the inner wall of the threaded sleeve.

[0009] A further improvement is that a sealing ring is fixed at one end of the connecting pipe near the exhaust pipe, and a sealing groove adapted to the sealing ring is opened at one end of the exhaust pipe near the connecting pipe.

[0010] A further improvement is that a first limiting ring is fixed to the inner wall of the connecting pipe, a second limiting ring is fixed to the inner wall of the exhaust pipe, and the flue gas filter plate is clamped between the first limiting ring and the second limiting ring.

[0011] A further improvement is made in that: the end of the gas combustion furnace away from the hot air output pipe is fixed to the inner wall of the air preheating cylinder away from the hot air output pipe; the outer wall of the air preheating cylinder away from the hot air output pipe is fixed with a burner and a gas input pipe; the output end of the burner and the outlet of the gas input pipe both penetrate into the interior of the gas combustion furnace; and an exhaust pipe connected to the preheating hood is fixed at the bottom of the air preheating cylinder.

[0012] A further improvement is that: an exhaust fan is fixed inside the cold air inlet pipe, and a filter pipe is threaded onto one end of the cold air inlet pipe located outside the air preheating cylinder, with a dust filter screen fixed inside the filter pipe.

[0013] The beneficial effects of this utility model are as follows: This utility model includes a gas combustion furnace. By embedding and inserting a flue gas filter plate inside the flue pipe, and locking the flue pipe and connecting pipe with a threaded locking mechanism, a sealed connection between the flue pipe and connecting pipe is achieved, and the flue gas filter plate is fixed and limited. This allows for convenient disassembly and installation of the flue gas filter plate, making cleaning and replacement of the flue gas filter plate easier and more convenient to use. Furthermore, by fixing a preheating hood to the inner wall of the air preheating cylinder, and introducing the high-temperature flue gas generated during gas combustion into the preheating hood through the flue pipe and connecting pipe, the outside cold air is preheated before being heated, thereby increasing the heating efficiency of the cold air and achieving effective recovery of the waste heat of the high-temperature flue gas in the gas combustion furnace. The recovered waste heat can be directly applied to the gas combustion furnace, making it highly practical. Attached Figure Description

[0014] Figure 1 This is a front view of the present invention;

[0015] Figure 2 This is a front sectional view of the present invention;

[0016] Figure 3 This is a side sectional view of the present invention;

[0017] Figure 4 This is the utility model Figure 3 Enlarged view of point A in the image;

[0018] Figure 5 This is a cross-sectional view of the cold air inlet pipe of this utility model;

[0019] Figure 6 This is a three-dimensional structural diagram of the gas combustion furnace of this utility model.

[0020] The components include: 1. Gas-fired combustion furnace; 2. Air heating cylinder; 3. Hot air output pipe; 4. Air preheating cylinder; 5. Cold air input pipe; 6. Exhaust pipe; 7. Connecting pipe; 8. Flue gas filter plate; 9. Preheating hood; 10. Heat recovery rigid pipe; 11. Heat recovery flexible hose; 12. Support rod; 13. Threaded sleeve pipe; 14. Limiting protrusion ring; 15. Limiting groove; 16. Sealing ring; 17. Sealing groove; 18. First limiting ring; 19. Second limiting ring; 20. Burner; 21. Gas input pipe; 22. Exhaust pipe; 23. Exhaust fan; 24. Filter pipe. Detailed Implementation

[0021] To deepen the understanding of this utility model, the following detailed description will be provided in conjunction with embodiments. These embodiments are only used to explain this utility model and do not constitute a limitation on the scope of protection of this utility model.

[0022] according to Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 As shown, this embodiment provides a gas-fired hot air furnace with waste heat recovery function, including a gas-fired furnace 1 for gas combustion and an air heating cylinder 2 located outside the gas-fired furnace 1. A hot air output pipe 3 for hot air exhaust is fixed to the right side wall of the air heating cylinder 2. A control valve is installed on the hot air output pipe 3. The left end of the air heating cylinder 2 is designed to be open so that air can enter it. An air preheating cylinder 4 for preheating the outside cold air is fixed to the outer wall of the air heating cylinder 2. A cold air input pipe 5, which is symmetrically distributed vertically, is welded and fixed to the right side wall of the air preheating cylinder 4 for introducing outside cold air. Exhaust pipes 6 for exhausting the high-temperature flue gas generated during gas combustion are fixed to both the front and rear side walls of the gas-fired furnace 1. The end of the exhaust pipe 6 away from the gas-fired furnace 1 extends to the outside of the air preheating cylinder 4. A connecting pipe 7 is connected to the end of the exhaust pipe 6 away from the gas-fired furnace 1. The exhaust pipe 6 and the connecting pipe 7 are locked and fixed by a threaded locking machine to achieve a sealed connection. A valve for heat recovery is inserted into the side of the exhaust pipe 6 near the connecting pipe 7. A flue gas filter plate 8, which filters and intercepts dust in high-temperature flue gas, is fixedly positioned within the exhaust pipe 6 when the exhaust pipe 6 and connecting pipe 7 are connected. A preheating hood 9 is welded and fixed to the inner wall of the air preheating cylinder 4, and the preheating hood 9 is connected to the connecting pipe 7 to contain the high-temperature flue gas. An exhaust pipe 22, connected to the preheating hood 9, is fixed to the bottom of the air preheating cylinder 4 to discharge the filtered flue gas to the outside. The flue gas filter plate 8 is inserted and fitted into the exhaust pipe 6, and the exhaust pipe 6 and connecting pipe 7 are connected by a threaded locking mechanism. The connecting pipe 7 is locked and fixed to achieve a sealed connection between the exhaust pipe 6 and the connecting pipe 7, and to fix and limit the flue gas filter plate 8, so that the flue gas filter plate 8 can be easily disassembled and installed. By fixing the preheating hood 9 to the inner wall of the air preheating cylinder 4, and introducing the high-temperature flue gas generated during the combustion of gas into the preheating hood 9 through the exhaust pipe 6 and the connecting pipe 7, the outside cold air is preheated before being heated, so that the heating efficiency of the cold air is higher, and the waste heat of the high-temperature flue gas in the gas combustion furnace 1 is effectively recovered.

[0023] Heat recovery rigid pipes 10 are fixed to both the front and rear side walls of the air preheating cylinder 4, and the heat recovery rigid pipes 10 are connected to the preheating hood 9. A heat recovery flexible hose 11 with certain elasticity is connected between the heat recovery rigid pipe 10 and the connecting pipe 7. The connection between the connecting pipe 7 and the preheating hood 9 is achieved through the heat recovery rigid pipe 10 and the heat recovery flexible hose 11. In order to avoid heat loss, the exhaust pipe 6, the connecting pipe 7, the heat recovery flexible hose 11 and the heat recovery rigid pipe 10 are all made of heat-insulating material and are heat-insulated. Four sets of symmetrically distributed support rods 12 are fixed to the outer wall of the air heating cylinder 2 by bolts. The end of the support rod 12 away from the air heating cylinder 2 is fixed to the inner wall of the air preheating cylinder 4 by bolts to improve the structural strength.

[0024] The threaded locking mechanism includes a threaded sleeve 13 and a limiting protrusion ring 14. The threaded sleeve 13 is slidably sleeved on the outer wall of the connecting pipe 7, and the inner wall of the threaded sleeve 13 near the exhaust pipe 6 has an internal thread. The limiting protrusion ring 14 is fixed to the outer wall of the connecting pipe 7. The inner wall of the threaded sleeve 13 near the connecting pipe 7 has a limiting groove 15, and the limiting groove 15 is adapted to the limiting protrusion ring 14. The cooperation between the limiting protrusion ring 14 and the limiting groove 15 plays a limiting role in the threaded sleeve 13, realizing the sliding connection of the threaded sleeve 13 while preventing it from falling off. The outer wall of the exhaust pipe 6 near the connecting pipe 7 has an external thread adapted to the internal thread of the inner wall of the threaded sleeve 13. By screwing the threaded sleeve 13 onto the exhaust pipe 6, the connecting pipe 7 is driven to continuously move towards the exhaust pipe 6 until the connecting pipe 7 and the exhaust pipe 6 are tightly connected.

[0025] A sealing ring 16 is fixed at one end of the connecting pipe 7 near the exhaust pipe 6. A sealing groove 17 is provided at one end of the exhaust pipe 6 near the connecting pipe 7, and the sealing groove 17 is adapted to the sealing ring 16. When the connecting pipe 7 and the exhaust pipe 6 are connected, the sealing ring 16 is embedded in the sealing groove 17, thereby improving the sealing performance between the connecting pipe 7 and the exhaust pipe 6.

[0026] A first limiting ring 18 is fixed to the inner wall of the connecting pipe 7, and a second limiting ring 19 is fixed to the inner wall of the exhaust pipe 6. When the connecting pipe 7 and the exhaust pipe 6 are connected, the flue gas filter plate 8 is clamped between the first limiting ring 18 and the second limiting ring 19, and is thus limited and fixed.

[0027] The left end of the gas combustion furnace 1 is fixed to the inner left wall of the air preheating cylinder 4 by bolts. The outer left wall of the air preheating cylinder 4 is fixed with a burner 20 and a gas input pipe 21 by bolts. A valve is installed on the gas input pipe 21 to control the gas flow. The output end of the burner 20 and the outlet of the gas input pipe 21 both penetrate into the interior of the gas combustion furnace 1. The gas input into the gas combustion furnace 1 is ignited by the burner 20 to achieve gas combustion. Gas combustion is an existing technology, and its principle will not be elaborated.

[0028] A fan 23 is fixed inside the cold air inlet pipe 5 by bolts, which facilitates drawing outside air into the air preheating cylinder 4. A filter pipe 24 is threaded onto one end of the cold air inlet pipe 5 outside the air preheating cylinder 4. A dust filter screen is fixed inside the filter pipe 24, which filters and intercepts dust in the outside air.

[0029] In actual use, the gas-fired hot air furnace with waste heat recovery function is fed into the gas combustion furnace 1 through the gas input pipe 21, ignited by the output end of the burner 20, and burned in the gas combustion furnace 1. The combustion raises the temperature of the gas combustion furnace 1. At this time, cold air is injected into the air preheating cylinder 4 through the cold air input pipe 5. The high-temperature flue gas generated during the gas combustion process is filtered and purified by the flue gas filter plate 8 in the exhaust pipe 6 and then injected into the preheating hood 9 through the connecting pipe 7 to preheat the cold air in the air preheating cylinder 4, realizing the recovery and utilization of the waste heat of the high-temperature flue gas. The preheated air then flows into the inner side of the air heating cylinder 2 and exchanges heat with the high-temperature gas combustion furnace 1, so that the preheated air is heated and the temperature is raised. The hot air is then discharged through the hot air output pipe 3 and delivered to the corresponding equipment that needs hot air (such as inputting the corresponding material drying equipment to dry the material).

[0030] When it is necessary to disassemble the flue gas filter plate 8 inside the exhaust pipe 6 for cleaning or replacement, first use the threaded locking mechanism to release the seal between the exhaust pipe 6 and the connecting pipe 7, then separate the exhaust pipe 6 and the connecting pipe 7. Next, remove the flue gas filter plate 8 directly from the exhaust pipe 6 to complete the disassembly. Then clean the disassembled flue gas filter plate 8, and then put the new flue gas filter plate 8 into the exhaust pipe 6. Then connect the connecting pipe 7 to the exhaust pipe 6, and use the threaded locking mechanism to lock and fix the exhaust pipe 6 and the connecting pipe 7, thus completing the convenient installation of the flue gas filter plate 8.

[0031] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A gas-fired hot air furnace with waste heat recovery function, comprising a gas-fired combustion furnace (1), characterized in that: An air heating cylinder (2) is provided on the outside of the gas combustion furnace (1). A hot air output pipe (3) is fixed on the side wall of the air heating cylinder (2). The end of the air heating cylinder (2) away from the hot air output pipe (3) is designed to be open. An air preheating cylinder (4) is fixed on the outer wall of the air heating cylinder (2). A cold air input pipe (5) is symmetrically fixed on the side of the air preheating cylinder (4) near the hot air output pipe (3). Both the front and rear side walls of the gas combustion furnace (1) are fixed with exhaust pipes (6) that penetrate to the outside of the air preheating cylinder (4). The end of the exhaust pipe (6) away from the gas combustion furnace (1) is sealed and connected to a connecting pipe (7) by a threaded locking mechanism. A flue gas filter plate (8) is inserted into the side of the exhaust pipe (6) near the connecting pipe (7). A preheating cover (9) connected to the connecting pipe (7) is fixed on the inner wall of the air preheating cylinder (4).

2. A gas-fired hot air furnace with waste heat recovery function according to claim 1, characterized in that: The air preheating cylinder (4) has heat recovery hard pipes (10) fixed on both the front and rear side walls, which are connected to the preheating cover (9). A heat recovery hose (11) is connected between the heat recovery hard pipe (10) and the connecting pipe (7). Support rods (12) are symmetrically fixed between the inner wall of the air preheating cylinder (4) and the outer wall of the air heating cylinder (2).

3. A gas-fired hot air furnace with waste heat recovery function according to claim 1, characterized in that: The threaded locking mechanism includes a threaded sleeve (13) that is slidably sleeved on the outer wall of the connecting pipe (7) and a limiting protrusion (14) fixed on the outer wall of the connecting pipe (7). The inner wall of the threaded sleeve (13) near the connecting pipe (7) is provided with a limiting groove (15) that matches the limiting protrusion (14). The outer wall of the exhaust pipe (6) near the connecting pipe (7) is provided with an external thread that matches the internal thread of the inner wall of the threaded sleeve (13).

4. A gas-fired hot air furnace with waste heat recovery function according to claim 1, characterized in that: A sealing ring (16) is fixed at one end of the connecting pipe (7) near the exhaust pipe (6), and a sealing groove (17) adapted to the sealing ring (16) is opened at one end of the exhaust pipe (6) near the connecting pipe (7).

5. A gas-fired hot air furnace with waste heat recovery function according to claim 1, characterized in that: The inner wall of the connecting pipe (7) is fixed with a first limiting ring (18), the inner wall of the exhaust pipe (6) is fixed with a second limiting ring (19), and the flue gas filter plate (8) is clamped between the first limiting ring (18) and the second limiting ring (19).

6. A gas-fired hot air furnace with waste heat recovery function according to claim 1, characterized in that: The end of the gas-fired furnace (1) away from the hot air output pipe (3) is fixed to the inner wall of the air preheating cylinder (4) away from the hot air output pipe (3). The outer wall of the air preheating cylinder (4) away from the hot air output pipe (3) is fixed with a burner (20) and a gas input pipe (21). The output end of the burner (20) and the outlet of the gas input pipe (21) both penetrate into the interior of the gas-fired furnace (1). The bottom end of the air preheating cylinder (4) is fixed with an exhaust pipe (22) that communicates with the preheating hood (9).

7. A gas-fired hot air furnace with waste heat recovery function according to claim 1, characterized in that: The cold air input pipe (5) has an exhaust fan (23) fixed inside. The end of the cold air input pipe (5) located outside the air preheating cylinder (4) is threaded with a filter pipe (24). A dust filter screen is fixed inside the filter pipe (24).

Images