Boiler flue gas waste heat recycling mechanism

Abstract

The utility model relates to the technical field of boilers, and discloses a boiler smoke waste heat recycling mechanism which comprises a boiler body, the boiler body is communicated with a smoke exhaust channel, a bypass pipeline is arranged on one side of the smoke exhaust channel, and the air inlet end and the air outlet end of the bypass pipeline are both communicated with the smoke exhaust channel. The bypass pipeline is communicated with a tail smoke return assembly, a filter screen is arranged in the bypass pipeline, a pulse valve is arranged on the bypass pipeline, and a switching assembly is arranged between the bypass pipeline and the smoke exhaust channel. The tail smoke return assembly is arranged, smoke flowing through the bypass pipeline can be partially extracted and conveyed to the hearth of the boiler body through the smoke return pipe to participate in combustion, and the pulse valve can regularly conduct pulse cleaning on the bypass pipeline and a filter screen in the bypass pipeline. The cleaned large-particle dust can be sucked by an induced draft fan of the tail smoke return assembly and conveyed to a hearth of the boiler body to participate in combustion, and the utilization rate of resources is increased.

Description

Technical Field

[0001] The utility model relates to the technical field of boilers, in particular to a boiler flue gas waste heat recycling mechanism. Background Art

[0002] During the operation of the boiler, a large amount of high-temperature flue gas is generated. The flue gas contains abundant heat energy. If it is not utilized, the heat energy will be wasted with the flue gas discharge. In addition, the flue gas contains a large amount of unburned dust particles, which will cause a large amount of energy waste if discharged directly. In order to solve the above problems, we propose a boiler flue gas waste heat recycling mechanism. Utility Model Content

[0003] The utility model aims to provide a boiler flue gas waste heat recycling mechanism to solve the problem of energy waste.

[0004] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a boiler flue gas waste heat recycling mechanism, comprising a boiler body, the flue gas outlet of the boiler body is connected to a smoke exhaust channel connected to the dust suction end of a dust collector, a bypass pipe is provided on one side of the smoke exhaust channel, the air inlet end and the air outlet end of the bypass pipe are both connected to the smoke exhaust channel, the bypass pipe is connected to a tail flue gas return assembly connected to the interior of the boiler body, a filter is provided in the bypass pipe, a pulse valve is provided on the bypass pipe, and a switching assembly is provided between the bypass pipe and the smoke exhaust channel.

[0005] According to the above technical solution, a primary air supply port is provided at the bottom of the boiler body, and a secondary air supply port is also provided on the boiler body. A smoke return port is provided on one side of the boiler body close to the primary air supply port and the secondary air supply port, and the smoke return port is provided between the primary air supply port and the secondary air supply port, and the tail smoke return assembly is connected to the smoke return port.

[0006] According to the above technical solution, a first guide plate is fixedly connected to the side wall of the boiler body near the primary air supply port, and a second guide plate is fixedly connected to the side wall of the boiler body near the secondary air supply port, and an independent air duct is formed between the first guide plate and the second guide plate.

[0007] According to the above technical solution, the smoke exhaust channel includes an intermediate pipe, both ends of the intermediate pipe are connected with connecting pipes, the two connecting pipes are respectively connected with the smoke outlet of the boiler body and the dust suction end of the dust collector, and the switching component includes a smoke baffle, which is rotatably arranged in the intermediate pipe.

[0008] According to the above technical solution, a limiting groove for limiting the rotation trajectory of the smoke baffle is provided in the connecting pipe.

[0009] According to the above technical solution, bosses are provided at both ends of the intermediate pipe.

[0010] According to the above technical solution, the tail smoke return assembly includes an induced draft fan, the air inlet end of the induced draft fan is connected to the bypass duct, and the air outlet end of the induced draft fan is connected to the inside of the boiler body.

[0011] According to the above technical solution, the flue gas waste heat recycling mechanism includes a preheating water tank, the tail flue gas return assembly includes a return smoke pipe, the end of the return smoke pipe passes through the preheating water tank and is connected to the interior of the boiler body, a boiler water supply port is provided on the top of the boiler body, and a liquid outlet is provided on the preheating water tank, and the liquid outlet is connected to the boiler water supply port through a water pipe.

[0012] According to the above technical solution, the part of the smoke return pipe located in the preheating water tank is arranged in an S shape, and the outer wall of the part of the smoke return pipe located in the preheating water tank is fixedly connected with heat exchange fins.

[0013] According to the above technical solution, the bypass pipe is a V-shaped pipe, the bend of the V-shaped pipe is set downward, the tail smoke return assembly is connected to the bend of the V-shaped pipe, and the filter is arranged directly above the bend of the V-shaped pipe.

[0014] Compared with the prior art, the beneficial effects of the utility model are:

[0015] The utility model is provided with a tail flue gas return assembly and a bypass duct, which can partially extract the flue gas circulating through the bypass duct, and send it to the furnace of the boiler body through the smoke return pipe to participate in combustion. A filter and a pulse valve are provided on the bypass duct, which can filter the flue gas in advance to leave large particles of dust in the bypass duct, and is connected to an external air source through the pulse valve. The bypass duct and the filter therein can be pulse-cleaned regularly, and the large particles of dust cleaned will be sucked by the induced draft fan of the tail flue gas return assembly and transported to the furnace of the boiler body to participate in combustion, thereby improving resource utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the waste heat recycling mechanism of the utility model;

[0017] Figure 2 It is a three-dimensional diagram of the boiler body of the utility model;

[0018] Figure 3 It is a schematic diagram of the interior of the waste heat recycling mechanism of the utility model;

[0019] Figure 4 It is a schematic diagram of the smoke exhaust channel and bypass pipe of the utility model;

[0020] Figure 5 This utility model Figure 3Enlarged schematic diagram of part A in the middle.

[0021] In the figure:

[0022] 1. Boiler body; 2. Smoke exhaust channel; 21. Intermediate pipe; 22. Connecting pipe; 3. Bypass pipe; 4. Tail smoke return assembly; 41. Draft fan; 42. Smoke return pipe; 5. Filter; 6. Switching assembly; 61. Smoke baffle; 62. Limiting groove; 63. Boss; 7. Primary air supply port; 8. Secondary air supply port; 9. Smoke return port; 11. First guide plate; 12. Second guide plate; 13. Preheating water tank; 14. Boiler water supply port; 15. Liquid outlet; 16. Heat exchange fins; 17. Pulse valve. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] See also Figure 1-5 The utility model provides a technical solution for a boiler flue gas waste heat recycling mechanism: it includes a boiler body 1, the flue gas outlet of the boiler body 1 is connected to a smoke exhaust channel 2 connected to the dust suction end of the dust collector, and the smoke generated by the boiler body 1 will enter the dust collector through the smoke exhaust channel 2 under the attraction of the dust collector and be purified by the dust collector to prevent large dust particles from being discharged into the air.

[0025] A bypass pipe 3 is provided on one side of the smoke exhaust channel 2. The air inlet and air outlet ends of the bypass pipe 3 are connected to the smoke exhaust channel 2. The smoke exhaust channel 2 and the bypass pipe 3 are both used for the circulation of smoke. A switching component 6 is provided between the bypass pipe 3 and the smoke exhaust channel 2. The switching component 6 can be used to select the path for the smoke circulation, that is, to select the circulation between the smoke exhaust channel 2 and the bypass pipe 3 (the smoke only circulates through a single pipe).

[0026] The bypass pipe 3 is connected to a tail flue gas return assembly 4 which is connected to the interior of the boiler body 1. When the switching assembly 6 switches the flue gas to circulate through the bypass pipe 3, the tail flue gas return assembly 4 can partially extract the flue gas circulating through the bypass pipe 3 and send it to the furnace of the boiler body 1 to participate in combustion, thereby improving resource utilization. The transported flue gas can also carry heat into the furnace to reduce heat loss of the flue gas.

[0027] Under normal conditions, the switching component 6 will switch the flue gas flow pipeline to the bypass pipe 3. A filter 5 is provided in the bypass pipe 3 to filter the flue gas in advance to leave large particles of dust in the bypass pipe 3. The dust is then absorbed by the tail flue gas return component 4 and transported to the furnace of the boiler body 1 to participate in combustion, thereby further improving resource utilization.

[0028] A pulse valve 17 is provided on the bypass pipe 3, and the pulse valve 17 is connected to an external gas source. The bypass pipe 3 and the filter 5 therein can be pulse-cleaned regularly. The large particles of dust cleaned will be sucked by the tail flue gas return component 4 and transported to the furnace of the boiler body 1 to participate in combustion, thereby further improving the utilization rate of resources. When cleaning through the pulse valve 17, the switching component 6 will switch the flue gas flow pipeline to the exhaust channel 2, so that the bypass pipe 3 is temporarily closed.

[0029] Specifically, a primary air supply port 7 is provided at the bottom of the boiler body 1, which is mainly used to transport coal powder into the furnace through the burner and can supply the oxygen required for the ignition and combustion of volatile matters in the coal powder. A secondary air supply port 8 is also provided on the boiler body 1, which is mainly used to supply the oxygen required for complete combustion of the fuel and can fully mix the air and fuel. Through the disturbance of the secondary air, the combustion is rapid, intense and complete.

[0030] A smoke return port 9 is provided on one side of the boiler body 1 close to the primary air supply port 7 and the secondary air supply port 8. The smoke return port 9 is arranged between the primary air supply port 7 and the secondary air supply port 8. The tail flue gas smoke return component 4 is connected to the smoke return port 9. The smoke transported by the tail flue gas smoke return component 4 carries large particles of dust and heat which will be transported to the furnace of the boiler body 1 through the smoke return port 9. The smoke return port 9 is arranged on the same side of the primary air supply port 7 and the secondary air supply port 8, which can prevent the wind transported by the smoke return port 9 from causing vortexes to form in the furnace of the boiler body 1 and causing the furnace temperature to fluctuate, thereby affecting the combustion efficiency and stability.

[0031] Specifically, a first guide plate 11 is fixedly connected to the side wall of the boiler body 1 near the primary air supply port 7 to prevent convection between the wind delivered by the smoke return port 9 and the wind from the primary air supply port 7. A second guide plate 12 is fixedly connected to the side wall of the boiler body 1 near the secondary air supply port 8 to prevent convection between the wind delivered by the smoke return port 9 and the wind from the secondary air supply port 8. An independent air duct is formed between the first guide plate 11 and the second guide plate 12, so that the wind delivered by the smoke return port 9 will not disturb the balance in the furnace of the boiler body 1.

[0032] Specifically, the smoke exhaust channel 2 includes an intermediate pipe 21, both ends of which are connected with connecting pipes 22. The two connecting pipes 22 are respectively connected to the smoke outlet of the boiler body 1 and the dust suction end of the dust collector to form a complete air path. The switching component 6 includes a smoke baffle 61, which is connected to an external drive motor. The smoke baffle 61 is rotatably arranged in the intermediate pipe 21. The inlet and outlet of the bypass pipe 3 can be blocked by the set smoke baffle 61, so that the bypass pipe 3 is temporarily closed. When the bypass pipe 3 is cleaned by the pulse valve 17, the external drive motor will drive the smoke baffle 61 to rotate to block the inlet and outlet of the bypass pipe 3, and the smoke can flow to the dust collector through the smoke exhaust channel 2.

[0033] After cleaning is completed, the external drive motor drives the smoke baffle 61 to rotate to open the inlet and outlet of the bypass pipe 3, and to block the inlet and outlet of the intermediate pipe 21 between the inlet and outlet of the bypass pipe 3, so that the intermediate pipe 21 is closed.

[0034] Specifically, a limiting groove 62 for limiting the rotation trajectory of the smoke baffle 61 is provided in the connecting pipe 22 .

[0035] Specifically, bosses 63 are provided at both ends of the middle pipe 21, and the smoke baffle 61 can be rotated to fit with the bosses 63 to close the middle pipe 21 and improve the sealing performance of the closure.

[0036] Specifically, the tail flue gas return assembly 4 includes an induced draft fan 41, the air inlet end of the induced draft fan 41 is connected to the bypass duct 3, and the air outlet end of the induced draft fan 41 is connected to the inside of the boiler body 1, so as to extract large particles of dust in the tail flue gas and transport it to the furnace of the boiler body 1 to participate in combustion.

[0037] Specifically, the flue gas waste heat recycling mechanism includes a preheating water tank 13, and the tail flue gas return assembly 4 includes a return smoke pipe 42. The end of the return smoke pipe 42 passes through the preheating water tank 13 and is connected to the inside of the boiler body 1. The return smoke pipe 42 is a pipe for transporting the tail flue gas. The heat carried by the flue gas will heat the water in the preheating water tank 13. A boiler water supply port 14 is provided on the top of the boiler body 1, and a liquid outlet 15 is provided on the preheating water tank 13. The liquid outlet 15 is connected to the boiler water supply port 14 through a water pipe. The heated water in the preheating water tank 13 can be transported to the boiler water supply port 14 by a water pump, thereby improving the utilization rate of thermal energy.

[0038] Specifically, the portion of the smoke return pipe 42 located in the preheating water tank 13 is arranged in an S shape, and the outer wall of the portion of the smoke return pipe 42 located in the preheating water tank 13 is fixedly connected with heat exchange fins 16, which increases the residence time of the smoke in the smoke return pipe 42 in the preheating water tank 13 and the contact area of ​​the smoke return pipe 42 for exchanging heat with water, thereby improving the heat exchange efficiency.

[0039] Specifically, the bypass pipe 3 is a V-shaped pipe, and the bend of the V-shaped pipe is set downward. When the pulse valve 17 cleans the bypass pipe 3, large particles of dust can fall better through the slope of the V-shaped pipe, and the tail flue gas return component 4 is connected to the bend of the V-shaped pipe. The fallen large particles of dust will enter the tail flue gas return component 4 through the bend of the V-shaped pipe, thereby improving efficiency. The filter 5 is arranged directly above the bend of the V-shaped pipe, that is, directly above the intersection of the tail flue gas return component 4 and the V-shaped pipe. The large particles of dust blocked by the filter 5 can fall into the tail flue gas return component 4 better.

[0040] Working principle:

[0041] Under normal conditions, the flue gas generated by the boiler body 1 will enter the dust collector through the bypass pipe 3 under the attraction of the dust collector. The induced draft fan 41 of the tail flue gas return assembly 4 can partially extract the flue gas circulating through the bypass pipe 3, and send it to the furnace of the boiler body 1 through the return smoke pipe 42 to participate in combustion, thereby improving the utilization rate of resources. The transported flue gas can also carry heat into the furnace to reduce the heat loss of the flue gas.

[0042] A filter 5 is provided in the bypass pipe 3 to filter the flue gas in advance, so as to retain large dust particles in the bypass pipe 3. The dust particles are then transported to the furnace of the boiler body 1 to participate in combustion through the absorption of the tail flue gas return component 4, thereby further improving the utilization rate of resources.

[0043] The pulse valve 17 can regularly perform pulse cleaning on the bypass pipe 3 and the filter 5 therein. When pulse cleaning is performed by the pulse valve 17, the smoke baffle 61 can be driven to rotate by an external drive motor to block the inlet and outlet of the bypass pipe 3. The flue gas can flow to the dust collector through the smoke exhaust channel 2, and the large particles of dust cleaned will be absorbed by the tail flue gas return component 4 and transported to the furnace of the boiler body 1 to participate in combustion, thereby further improving resource utilization.

[0044] In the description of the present invention, it should be understood that the terms "coaxial", "bottom", "one end", "top", "middle", "the other end", "upper", "one side", "top", "inside", "front", "center", "both ends" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0045] In addition, the terms "first", "second", "third" and "fourth" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first", "second", "third" and "fourth" may explicitly or implicitly include at least one of such features.

[0046] In the present utility model, unless otherwise clearly stipulated and limited, the terms such as "installation", "setting", "connection", "fixation" and "screw-on" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, ordinary technicians in this field can understand the specific meanings of the above terms in the utility model according to the specific circumstances.

[0047] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A boiler flue gas waste heat recycling mechanism, comprising a boiler body (1), wherein the flue gas outlet of the boiler body (1) is connected to a flue gas exhaust passage (2) connected to a dust collecting end of a dust collector, and characterized in that: A bypass pipe (3) is provided on one side of the smoke exhaust channel (2); the air inlet end and the air outlet end of the bypass pipe (3) are both connected to the smoke exhaust channel (2); the bypass pipe (3) is connected to a tail smoke return assembly (4) connected to the inside of the boiler body (1); a filter (5) is provided in the bypass pipe (3); a pulse valve (17) is provided on the bypass pipe (3); and a switching assembly (6) is provided between the bypass pipe (3) and the smoke exhaust channel (2).

2. A boiler flue gas waste heat recycling mechanism according to claim 1, characterized in that: A primary air supply port (7) is provided at the bottom of the boiler body (1), and a secondary air supply port (8) is also provided on the boiler body (1). A smoke return port (9) is provided on one side of the boiler body (1) close to the primary air supply port (7) and the secondary air supply port (8), and the smoke return port (9) is provided between the primary air supply port (7) and the secondary air supply port (8), and the tail smoke return assembly (4) is connected to the smoke return port (9).

3. A boiler flue gas waste heat recycling mechanism according to claim 2, characterized in that: A first guide plate (11) is fixedly connected to the side wall of the boiler body (1) close to the primary air supply port (7), and a second guide plate (12) is fixedly connected to the side wall of the boiler body (1) close to the secondary air supply port (8), and an independent air duct is formed between the first guide plate (11) and the second guide plate (12).

4. A boiler flue gas waste heat recycling mechanism according to claim 1, characterized in that: The smoke exhaust channel (2) comprises an intermediate pipe (21), both ends of the intermediate pipe (21) are connected to connecting pipes (22), the two connecting pipes (22) are respectively connected to the smoke outlet of the boiler body (1) and the dust suction end of the dust collector, and the switching component (6) comprises a smoke baffle (61), and the smoke baffle (61) is rotatably arranged in the intermediate pipe (21).

5. A boiler flue gas waste heat recycling mechanism according to claim 4, characterized in that: The connecting pipe (22) is provided with a limiting groove (62) for limiting the rotation track of the smoke baffle (61).

6. A boiler flue gas waste heat recycling mechanism according to claim 4, characterized in that: Bosses (63) are provided at both ends of the intermediate pipe (21).

7. The boiler flue gas waste heat recycling mechanism according to claim 1, characterized in that: The tail smoke return assembly (4) comprises an induced draft fan (41), the air inlet end of the induced draft fan (41) is connected to the bypass duct (3), and the air outlet end of the induced draft fan (41) is connected to the inside of the boiler body (1).

8. The boiler flue gas waste heat recycling mechanism according to claim 1, characterized in that: The flue gas waste heat recycling mechanism comprises a preheating water tank (13), the tail flue gas return assembly (4) comprises a return pipe (42), the end of the return pipe (42) passes through the preheating water tank (13) and is connected to the inside of the boiler body (1), the top of the boiler body (1) is provided with a boiler water supply port (14), the preheating water tank (13) is provided with a liquid outlet (15), and the liquid outlet (15) is connected to the boiler water supply port (14) through a water pipe.

9. A boiler flue gas waste heat recycling mechanism according to claim 8, characterized in that: The portion of the smoke return pipe (42) located in the preheating water tank (13) is arranged in an S shape, and the outer wall of the portion of the smoke return pipe (42) located in the preheating water tank (13) is fixedly connected with a heat exchange fin (16).

10. The boiler flue gas waste heat recycling mechanism according to claim 1, characterized in that: The bypass pipe (3) is a V-shaped pipe, the bend of the V-shaped pipe is arranged downward, the tail smoke return assembly (4) is connected to the bend of the V-shaped pipe, and the filter (5) is arranged directly above the bend of the V-shaped pipe.

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