Air and smoke mixer

Abstract

The present invention relates to an air and flue gas mixer in the technical field of flue gas mixing devices, comprising an outer cylinder and an inner cylinder, the inner cylinder being connected to the inner wall of the outer cylinder through a bracket, a first louver regulating damper being arranged between the inner cylinder and the outer cylinder, a second louver regulating damper being arranged in the inner cylinder, the first louver regulating damper comprising a thermal expansion mechanism, a first reset mechanism and a plurality of fan-shaped baffles rotatably connected between the inner cylinder and the outer cylinder, the baffle shafts of the fan-shaped baffles being uniformly distributed on the outer circular wall of the inner cylinder along the circumferential direction, the thermal expansion mechanism being able to generate a driving force for rotating the fan-shaped baffles as the flue gas temperature increases, the second louver regulating damper comprising a second reset mechanism and a plurality of windshields rotatably connected in the inner cylinder, the windshield being able to automatically adjust the opening under the cooperation of the second reset mechanism according to the pressure difference on both sides of the second louver regulating damper. The device has low manufacturing and operation and maintenance costs, can independently realize efficient proportional adjustment of air and flue gas, and is conducive to ensuring low nitrogen combustion and energy-saving effects of the boiler.

Description

Technical Field

[0001] The invention belongs to the technical field of smoke mixing devices, and in particular relates to an air and smoke mixer. Background Art

[0002] In order to achieve low-nitrogen combustion and energy saving in industrial boilers, a flue gas recirculation technology has appeared on the market in recent years, which introduces high-temperature flue gas into the air inlet duct of the boiler blower through a recirculation flue. However, in the existing flue gas recirculation technology, the regulation of air and flue gas requires an external power mechanism to adjust, which has a complex structure, high manufacturing and operation and maintenance costs, and a large hysteresis, which can easily cause fluctuations in the operating conditions in the furnace and affect the low-nitrogen combustion and energy-saving effects. Therefore, how to independently achieve efficient ratio adjustment of air and flue gas according to the oxygen demand for combustion in the furnace without external power has become a technical problem that technical personnel in this field need to overcome urgently. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0004] An air and smoke mixer, comprising an outer cylinder and an inner cylinder, wherein the inner cylinder is connected to the inner wall of the outer cylinder through a bracket, and an annular first smoke channel is formed between the inner cylinder and the outer cylinder, and the inner cavity of the inner cylinder forms a second smoke channel, a first louver regulating damper is arranged in the first smoke channel, and a second louver regulating damper is arranged in the second smoke channel, the first louver regulating damper comprises a thermal expansion mechanism, a first reset mechanism and a plurality of fan-shaped baffles rotatably connected between the inner cylinder and the outer cylinder, and the baffle shafts of the fan-shaped baffles are uniformly distributed in the circumferential direction. On the outer circular wall of the inner cylinder, the thermal expansion mechanism can generate a driving force to rotate the fan-shaped baffle as the smoke temperature increases. The first reset mechanism can drive the fan-shaped baffle to rotate and reset when the smoke temperature decreases. The second louver regulating damper includes a second reset mechanism and a plurality of wind shields rotatably connected to the inner cylinder. The wind shield can automatically adjust the opening according to the pressure difference on both sides of the second louver regulating damper with the cooperation of the second reset mechanism. When the pressure difference on both sides of the second louver regulating damper disappears, the second reset mechanism is used to drive the wind shield to reset.

[0005] Preferably, the thermal expansion mechanism includes a sliding sleeve coaxially sleeved on the outside of the inner cylinder and a temperature difference driving component capable of driving the sliding sleeve to translate axially along the inner cylinder, the temperature difference driving component includes at least two synchronous telescopic cylinders uniformly distributed along the circumferential direction at the right end of the outer wall of the inner cylinder, an expansion chamber is provided in the synchronous telescopic cylinder, a piston is slidably connected in the expansion chamber, the expansion chamber at the right end of the piston is filled with an expansion fluid whose volume changes with temperature, and a piston rod is connected to the left end of the piston, the left end of the piston rod extends out of the expansion chamber and is connected to or conflicts with the right end of the sliding sleeve, and the first reset mechanism includes a first A spring and a limit plate sleeved on the left end of the outer wall of the inner cylinder, the left end of the first spring is connected to or in conflict with the limit plate, and the right end is connected to or in conflict with the left end face of the sliding sleeve, the sliding sleeve is evenly distributed with a plurality of tooth grooves arranged parallel to the axial direction of the inner cylinder along the circumferential direction, the number of the tooth grooves is the same as the number of the fan-shaped baffles, and the tooth grooves and the fan-shaped baffles are arranged one by one, the baffle shaft of the fan-shaped baffle passes through the middle of the tooth groove, a tooth plate is arranged on one side of the inner wall of the tooth groove, the tooth plate is arranged parallel to the axial direction of the inner cylinder, and a rotating gear is sleeved on the baffle shaft, the rotating gear is arranged in the tooth groove and meshed with the tooth plate. Through the arrangement of the thermal expansion mechanism and the first reset mechanism, the driving force can be generated by the change of the flue gas temperature to realize the autonomous adjustment of the opening of the fan-shaped baffle.

[0006] Preferably, when the left end of the piston rod extends out of the expansion chamber and is connected to the right end of the sliding sleeve, the first reset mechanism is a reset spring arranged in the expansion chamber, and the reset spring abuts against the left end face of the piston, and is used to drive the piston to move rightward when the expansion fluid cools down and contracts. By setting the thermal expansion mechanism and the first reset mechanism, the driving force can be generated by the change of the flue gas temperature, so as to realize the autonomous adjustment of the opening of the fan-shaped baffle.

[0007] Preferably, a mounting seat is provided at the bottom of the synchronous telescopic cylinder, and the mounting seat is adjustably connected to the outer wall of the inner tube by bolts, and a long strip adjustment hole is provided on the mounting seat along the axial direction of the inner tube. The telescopic amount of the piston rod can be fine-tuned by adjusting the installation position of the mounting seat and the filling amount of the expansion liquid in the synchronous telescopic cylinder to meet the opening adjustment needs of the fan-shaped baffle.

[0008] Preferably, the synchronous telescopic cylinder is provided with a liquid injection hole, the liquid injection hole is connected to the right end of the expansion chamber, and a plug is threadedly connected to the liquid injection hole to facilitate adjustment of the filling amount of the expansion liquid.

[0009] Preferably, the second reset mechanism adopts a torsion spring or a second spring, the two ends of which are respectively connected to the inner wall of the inner tube and a side edge of the wind shield, and is used to drive the wind shield to reset when the airflow pressure acting on the wind shield disappears.

[0010] Preferably, two ends of the outer cylinder extend out of two ends of the inner cylinder respectively, and the two ends of the outer cylinder are connected between the recycling flue and the air inlet duct of the blower respectively by flange bolt connection or welding.

[0011] Preferably, high temperature resistant sealing strips are respectively provided around the peripheries of the fan-shaped baffle and the wind shield, so as to ensure the sealing of the first louver regulating damper and the second louver regulating damper respectively when the fan-shaped baffle and the wind shield are in a closed state.

[0012] Preferably, the high temperature resistant sealing strip is made of high temperature resistant rubber material.

[0013] The present invention also includes other devices or components that enable the air and smoke mixer to be used normally, all of which are conventional technical means in the field; in addition, the devices and components not limited in the present invention all adopt conventional technical means in the field.

[0014] The working principle of the invention is that when in use, the air outlet end of the device is connected to the flue gas connection side of the boiler blower inlet duct, and the air inlet end is connected to the recirculation flue. When the industrial boiler is operating normally, the boiler's combustion control system will adjust the opening of the blower according to the temperature conditions and air volume parameters in the furnace to change the air volume within a certain range. As the air volume changes, the negative pressure in the air inlet duct of the blower fluctuates, and the wind shield is twisted under the pressure of the air flow according to the pressure difference change on both sides of the second louver adjusting damper, so as to achieve the purpose of adjusting the amount of flue gas introduced according to the pressure difference change. As the flue gas is introduced, the thermal expansion mechanism is deformed by heat, driving the fan-shaped baffle of the first louver adjusting damper to twist, thereby introducing more flue gas into the furnace, thereby reducing the combustion intensity in the furnace and reducing the boiler exhaust temperature. When the exhaust gas temperature of the boiler decreases, the thermal expansion mechanism contracts and resets, and the first reset mechanism drives the fan-shaped baffle of the first louver regulating damper to twist and reset in the opposite direction, thereby reducing the amount of smoke entering. When the pressure difference on both sides of the second louver regulating damper disappears, the wind baffle is reset under the drive of the second reset mechanism, thereby achieving the closure of the second louver regulating damper.

[0015] Compared with the prior art, the present invention has the following beneficial effects: the device does not require an external power mechanism, has a simple structure, and has low manufacturing and operation and maintenance costs. It can independently achieve efficient ratio adjustment of air and flue gas according to the oxygen demand for combustion in the furnace, which helps to ensure the low-nitrogen combustion and energy-saving effect of the boiler. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0017] Figure 1 It is a schematic diagram of the overall structure of the present invention when the first louver regulating damper and the second louver regulating damper in Example 1 are in the open state.

[0018] Figure 2 yes Figure 1 AA section view structural diagram.

[0019] Figure 3 yes Figure 2 An enlarged schematic diagram of the G structure in FIG.

[0020] Figure 4 yes Figure 2 Schematic diagram of the enlarged structure of part H in .

[0021] Figure 5 It is a schematic diagram of the combined structure of the rotating gear and the tooth groove in Example 1 and Example 2.

[0022] Figure 6 It is a schematic diagram of the overall structure of the present invention when the first louver regulating damper and the second louver regulating damper in Example 2 are in the open state.

[0023] Figure 7 yes Figure 6 BB section structure schematic diagram.

[0024] Figure 8 yes Figure 7 Schematic diagram of the enlarged structure of the M part.

[0025] Fig. 9 yes Figure 7 An enlarged schematic diagram of the N-part structure. DETAILED DESCRIPTION

[0026] The present invention is described clearly below in conjunction with the drawings and specific embodiments in the embodiments of the present invention. The description herein is only used to explain the present invention, but is not intended to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work, any modifications, equivalent substitutions, improvements, etc., should be included in the protection scope of the present invention.

[0027] Example 1

[0028] like Figures 1 to 5As shown, the present invention provides an air and smoke mixer, comprising an outer tube 1 and an inner tube 2, wherein the inner tube 2 is connected to the inner wall of the outer tube 1 through a bracket 3, and a first annular smoke channel is formed between the inner tube 2 and the outer tube 1, and the inner cavity of the inner tube forms a second smoke channel, a first louver regulating damper is provided in the first smoke channel, and a second louver regulating damper is provided in the second smoke channel, the first louver regulating damper comprises a thermal expansion mechanism, a first reset mechanism and a plurality of fan-shaped baffles 4 rotatably connected between the inner tube 2 and the outer tube 1, and the baffle shaft of each fan-shaped baffle 4 5 are uniformly distributed on the outer circumferential wall of the inner tube 2 along the circumferential direction; the thermal expansion mechanism can generate a driving force to rotate the fan-shaped baffle 4 as the smoke temperature increases; the first reset mechanism can drive the fan-shaped baffle 4 to rotate and reset when the smoke temperature decreases; the second louver regulating damper includes a second reset mechanism and a plurality of windshields 6 rotatably connected to the inner tube 2; the windshields 6 can automatically adjust the opening according to the pressure difference on both sides of the second louver regulating damper with the cooperation of the second reset mechanism; when the pressure difference on both sides of the second louver regulating damper disappears, the second reset mechanism is used to drive the windshield 6 to reset.

[0029] The thermal expansion mechanism includes a sliding sleeve 8 coaxially sleeved on the outside of the inner tube 2 and a temperature difference driving component that can drive the sliding sleeve 8 to translate axially along the inner tube 2. The temperature difference driving component includes two synchronous telescopic cylinders 9 uniformly distributed along the circumferential direction at the right end of the outer wall of the inner tube 2. An expansion chamber is provided in the synchronous telescopic cylinder 9, and a piston is slidably connected in the expansion chamber. The expansion chamber at the right end of the piston is filled with an expansion liquid whose volume changes with temperature changes, and the left end of the piston is connected to a piston rod. The left end of the piston rod extends out of the expansion chamber and is connected to the right end of the sliding sleeve 8. The first reset mechanism includes a first spring 13 sleeved on the outside of the inner tube 2 and a first spring 13 sleeved on the left end of the outer wall of the inner tube 2. The limit plate 7, the left end of the first spring 13 is connected to the limit plate 7, and the right end is connected to the left end face of the sliding sleeve 8. The sliding sleeve 8 is evenly distributed with a plurality of tooth grooves 10 arranged parallel to the axial direction of the inner cylinder 2 along the circumferential direction. The number of the tooth grooves 10 is the same as the number of the fan-shaped baffles 4, and the tooth grooves 10 are arranged one by one with the fan-shaped baffles 4. The baffle shaft 5 of the fan-shaped baffle 4 passes through the middle of the tooth groove 10. A tooth plate 11 is arranged on one side of the inner wall of the tooth groove 10. The tooth plate 11 is arranged parallel to the axial direction of the inner cylinder 2. A rotating gear 12 is sleeved on the baffle shaft 5. The rotating gear 12 is arranged in the tooth groove 10 and meshed with the tooth plate 11. Through the arrangement of the thermal expansion mechanism and the first reset mechanism, the driving force can be generated by the change of the flue gas temperature to realize the autonomous adjustment of the opening of the fan-shaped baffle 4.

[0030] The synchronous telescopic cylinder 9 is provided with a mounting seat at the bottom, and the mounting seat is adjustably connected to the outer wall of the inner tube 2 by bolts, and a long strip adjustment hole is provided on the mounting seat along the axial direction of the inner tube 2, and the expansion amount of the piston rod can be fine-tuned by adjusting the mounting position of the mounting seat and the filling amount of the expansion liquid in the synchronous telescopic cylinder 9 to meet the opening adjustment needs of the fan-shaped baffle 4. The synchronous telescopic cylinder 9 is provided with a liquid injection hole, which is connected to the right end of the expansion chamber, and a plug is threadedly connected to the liquid injection hole to facilitate the adjustment of the filling amount of the expansion liquid.

[0031] The second reset mechanism uses a torsion spring 14, the two ends of which are respectively connected to the inner wall of the inner tube 2 and one side of the windshield 6, and are used to drive the windshield 6 to reset when the airflow pressure acting on the windshield 6 disappears. The two ends of the outer tube 1 extend out of the two ends of the inner tube 2, and the two ends of the outer tube 1 are respectively connected between the recirculation flue (not shown in the figure) and the air inlet duct of the blower (not shown in the figure) by welding. The peripheries of the fan-shaped baffle 4 and the windshield 6 are respectively provided with high-temperature resistant sealing strips (not shown in the figure), which are used to ensure the sealing of the first louver regulating damper and the second louver regulating damper when the fan-shaped baffle 4 and the windshield 6 are closed, and the high-temperature resistant sealing strips are made of high-temperature resistant rubber material.

[0032] The working principle of the invention is that when in use, the air outlet end of the device is connected to the flue gas connection side of the boiler blower inlet duct, and the air inlet end is connected to the recirculation flue. When the industrial boiler is operating normally, the boiler's combustion control system will adjust the opening of the blower according to the temperature conditions and air volume parameters in the furnace to change the air volume within a certain range. As the air volume changes, the negative pressure in the air inlet duct of the blower fluctuates. The wind shield 6 twists under the pressure of the air flow according to the pressure difference change on both sides of the second louver adjusting damper, so as to achieve the purpose of adjusting the amount of flue gas introduced according to the pressure difference change. As the flue gas is introduced, the thermal expansion mechanism is deformed by heat, driving the fan-shaped baffle 4 of the first louver adjusting damper to twist, thereby introducing more flue gas into the furnace, thereby reducing the combustion intensity in the furnace and reducing the boiler exhaust temperature. When the exhaust gas temperature of the boiler decreases, the thermal expansion mechanism contracts and resets, and the first reset mechanism drives the fan-shaped baffle 4 of the first louver regulating damper to reversely twist and reset, thereby reducing the amount of smoke entering. When the pressure difference on both sides of the second louver regulating damper disappears, the wind baffle 6 is reset under the drive of the second reset mechanism, thereby realizing the closure of the second louver regulating damper.

[0033] Example 2

[0034] As shown Figures 5 to 9As shown, the difference between Example 2 and Example 1 is that the first reset mechanism is a reset spring 15 arranged in the expansion chamber, and the reset spring 15 abuts against the left end face of the piston to drive the piston to move rightward when the expansion fluid cools down and contracts.

[0035] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. An air and flue gas mixer, characterized in that: The vents are connected to the inner wall of the outer cylinder by a bracket, and a first annular smoke passage is formed between the inner cylinder and the outer cylinder, and an inner cavity of the inner cylinder forms a second smoke passage, a first louver regulating damper is arranged in the first smoke passage, and a second louver regulating damper is arranged in the second smoke passage, the first louver regulating damper comprises a thermal expansion mechanism, a first reset mechanism and a plurality of fan-shaped baffles rotatably connected between the inner cylinder and the outer cylinder, the baffle shafts of the fan-shaped baffles are uniformly distributed on the outer circular wall of the inner cylinder along the circumferential direction, the thermal expansion mechanism can generate a driving force to rotate the fan-shaped baffles as the smoke temperature increases, the first reset mechanism can drive the fan-shaped baffles to rotate and reset when the smoke temperature decreases, the second louver regulating damper comprises a second reset mechanism and a plurality of windshields rotatably connected in the inner cylinder, the windshield can automatically adjust the opening degree under the cooperation of the second reset mechanism according to the pressure difference on both sides of the second louver regulating damper, and when the pressure difference on both sides of the second louver regulating damper disappears, the second reset mechanism is used to drive the windshield to reset; The thermal expansion mechanism comprises a sliding sleeve coaxially sleeved on the outside of the inner tube and a temperature difference driving assembly capable of driving the sliding sleeve to translate along the axial direction of the inner tube. The temperature difference driving assembly comprises at least two synchronous telescopic cylinders uniformly distributed along the circumferential direction at the right end of the outer wall of the inner tube. An expansion chamber is arranged in the synchronous telescopic cylinder. A piston is slidably connected in the expansion chamber. The expansion chamber at the right end of the piston is filled with an expansion liquid whose volume changes with temperature changes. The left end of the piston is connected with a piston rod. The left end of the piston rod extends out of the expansion chamber and is connected to or in conflict with the right end of the sliding sleeve. A plurality of tooth grooves are uniformly distributed along the circumferential direction on the sliding sleeve and are arranged parallel to the axial direction of the inner tube. The number of the tooth grooves is the same as the number of the fan-shaped baffles, and the tooth grooves and the fan-shaped baffles are arranged one by one. The baffle shaft of the fan-shaped baffle passes through the middle of the tooth groove. A tooth plate is arranged on one side of the inner wall of the tooth groove. The tooth plate is arranged parallel to the axial direction of the inner tube. A rotating gear is sleeved on the baffle shaft. The rotating gear is arranged in the tooth groove and meshed with the tooth plate. A mounting seat is provided at the bottom of the synchronous telescopic cylinder, and the mounting seat is adjustably connected to the outer wall of the inner tube by bolts, and a long strip adjustment hole is provided on the mounting seat along the axial direction of the inner tube; an injection hole is provided on the synchronous telescopic cylinder, and the injection hole is connected to the right end of the expansion chamber, and a plug is threadedly connected to the injection hole.

2. The air and smoke mixer according to claim 1, characterized in that: The first reset mechanism includes a first spring sleeved outside the inner cylinder and a limit plate sleeved on the left end of the outer wall of the inner cylinder. The left end of the first spring is connected to or in conflict with the limit plate, and the right end is connected to or in conflict with the left end surface of the sliding sleeve.

3. The air and flue gas mixer according to claim 1, characterized in that: The first reset mechanism is a reset spring disposed in the expansion chamber, the reset spring abuts against the left end surface of the piston, and is used to drive the piston to move rightward when the expansion fluid cools down and contracts.

4. The air and smoke mixer according to claim 1, characterized in that: The second reset mechanism adopts a torsion spring or a second spring, and the two ends of the torsion spring or the second spring are respectively connected to the inner wall of the inner tube and one side of the wind shield.

5. The air and smoke mixer according to claim 1, characterized in that: The two ends of the outer cylinder extend out of the two ends of the inner cylinder respectively, and the two ends of the outer cylinder are connected between the recirculation flue and the air inlet duct of the blower respectively by flange bolt connection or welding.

6. The air and smoke mixer according to claim 1, characterized in that: The peripheries of the fan-shaped baffle and the wind shield are respectively provided with high-temperature resistant sealing strips, which are used to ensure the sealing of the first louver regulating damper and the second louver regulating damper respectively when the fan-shaped baffle and the wind shield are in a closed state.

7. The air and smoke mixer according to claim 6, characterized in that: The high temperature resistant sealing strip is made of high temperature resistant rubber material.

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