Flue gas waste heat recovery device

Abstract

The utility model discloses a flue gas waste heat recovery device, which relates to the technical field of flue gas waste heat treatment, and comprises a flue gas heat exchanger, the front end and the rear end of the flue gas heat exchanger are respectively provided with a flue gas inlet and a flue gas outlet, a heat exchange assembly is arranged in the flue gas heat exchanger, and the heat exchange assembly comprises a plurality of heat exchange plates which are vertically arranged at intervals; heat exchange sub-runners are arranged between the heat exchange plates, heat exchange pipe grooves for installing heat exchange pipes are formed in the outer walls of the upper ends and the lower ends of the heat exchange plates, and communicating openings for communicating heat exchangers on the upper surface and the lower surface are formed in one ends of the heat exchange pipe grooves. The inner wall of the flue gas heat exchanger is provided with connecting pipe grooves used for connecting different levels of heat exchange pipes. The problems that in an existing flue gas waste heat recovery device, the heat exchange area is small, the heat exchange efficiency is low, flue gas is not prone to making contact with a heat exchange assembly, and flue gas waste heat recovery is affected are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of flue gas waste heat treatment, in particular to a flue gas waste heat recovery device. Background Art

[0002] Flue gas is the main way that general energy-consuming equipment wastes energy. For example, boiler exhaust consumes about 15% of energy. Other equipment, such as setting machines, dryers, and kilns in the printing and dyeing industry, consume most of their energy through flue gas emissions. Flue gas waste heat recovery mainly converts the heat carried by the flue gas into usable heat through some kind of heat exchange method.

[0003] For example, the public document: CN210952439U, named "A flue gas waste heat recovery device", includes a box body and a waste heat recovery box, the interior of the box body and the waste heat recovery box are provided with zigzag distributed and interconnected gas pipes, and a fan casing is provided near the top of the outer wall of the box body away from the waste heat recovery box, the side of the fan casing away from the box body is plugged with an air intake pipe, and the gas in the air intake pipe passes through the fan casing into the air intake pipe, the bottom inner wall of the box body is fixed with a second negative electrode rod and a second positive electrode rod by bolts, and the bottom end of the side of the box body away from the air intake pipe is plugged with a water pipe, the water pipe is connected to the waste heat recovery box, and the outer wall of the waste heat recovery box away from the box body is plugged with an exhaust pipe near the bottom end.

[0004] However, the heat exchange area of ​​the above-mentioned existing flue gas waste heat recovery device is small, the heat exchange efficiency is low, and the flue gas is not easy to contact the heat exchange components, which affects the recovery and use of the flue gas waste heat; therefore, it does not meet the existing needs. The applicant has proposed a flue gas waste heat recovery device. Utility Model Content

[0005] The purpose of the present utility model is to provide a flue gas waste heat recovery device to solve the problems proposed in the above background technology that the heat exchange area of ​​the existing flue gas waste heat recovery device is small, the heat exchange efficiency is low, and the flue gas is not easy to contact the heat exchange components, which affects the recovery and use of the flue gas waste heat.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a device for recovering waste heat from flue gas, comprising: a flue gas heat exchanger, wherein both the front and rear ends of the flue gas heat exchanger are provided with a flue gas inlet and outlet, a heat exchange component is provided inside the flue gas heat exchanger, and the heat exchange component includes a plurality of vertically spaced heat exchange plates, and heat exchange diversion channels are provided between the heat exchange plates. Heat exchange pipe grooves for installing heat exchange pipes are provided on the outer walls of the upper and lower ends of the heat exchange plates, and a connecting port for connecting the upper and lower surface heat exchangers is provided at one end of the heat exchange pipe groove, and a connecting pipe groove for connecting heat exchange pipes of different layers is provided on the inner wall of the flue gas heat exchanger.

[0007] Preferably, a water inlet for connecting to the end of the uppermost heat exchange plate is provided on the side wall of the flue gas heat exchanger, and a drainage outlet for connecting to the end of the lowermost heat exchange plate is provided below the water inlet.

[0008] Preferably, one end of the water inlet and the drain pipe is provided with a medium water heat exchange pipeline, and the end of the medium water heat exchange pipeline away from the flue gas heat exchanger is provided with a direct-fired heat pump.

[0009] Preferably, the inlet end of the direct-fired heat pump is connected to a natural gas pipeline, and one end of the direct-fired heat pump is connected to a flue gas conveying pipe through a flue gas pipeline.

[0010] Preferably, a smoke filter is provided between the smoke conveying pipe and the smoke pipeline.

[0011] Preferably, a flue gas exhaust pipe is provided at the outlet end of the flue gas heat exchanger, a chimney is provided at one end of the flue gas exhaust pipe, and a fan is provided at the front end of the chimney.

[0012] Preferably, a flue gas conveying pipe is provided at the inlet end of the flue gas heat exchanger, a gas hot water boiler is provided at one end of the flue gas conveying pipe, and a natural gas pipeline is provided at the inlet end of the gas hot water boiler.

[0013] Preferably, a heat network water supply pipeline is provided at the outlet end of the gas hot water boiler.

[0014] Preferably, a heat network return pipe is provided at the other inlet end of the gas hot water boiler, and one end of the heat network return pipe is connected to a direct-fired heat pump through a heat exchange and temperature-raising section.

[0015] Preferably, the heat exchange plate is made of aluminum, and the heat exchange tube groove is in the shape of a coiled tube.

[0016] Compared with the prior art, the beneficial effects of the present invention are:

[0017] The utility model recovers the waste heat of flue gas through the arrangement of heat exchange components, wherein high-temperature flue gas enters the flue gas heat exchanger from the flue gas inlet and outlet, and the flue gas is diverted and dispersed at the heat exchange plates at each level, so that the flue gas enters the heat exchange diversion channel between the upper and lower heat exchange plates, and is affected by the heat exchange of the media from the upper and lower levels. The connecting port can connect the heat exchange pipes on the upper and lower surfaces of the same heat exchange plate, and the heat exchange pipes at the heat exchange plates at different levels can be connected by connecting pipe grooves, so that the heat exchange pipes can be densely distributed on the surface of the heat exchange plates at each level from top to bottom, which can effectively increase the heat exchange area and increase the heat exchange efficiency.

[0018] Furthermore, the present application sets up a medium water heat exchange pipeline, a direct-fired heat pump, and a gas hot water boiler, so that the flue gas is always in contact with the heat exchange tubes located on the heat exchange tube groove during circulation. The heat exchange tubes are filled with heat exchange medium water, which gradually cools down the flue gas and gradually heats up the medium water. Finally, the flue gas is discharged from the other end, and the medium water is heated and transported to the direct-fired heat pump through the medium water heat exchange pipeline, transferring the heat to the heat network return water pipeline, forming waste heat recovery, and the heat network return water temperature increases. It then enters the boiler system, is heated to the heat network design temperature, and is sent to the heat network water supply pipeline for a heat supply cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the utility model;

[0020] Figure 2 This is a schematic diagram of the external structure of the flue gas heat exchanger of the present utility model;

[0021] Figure 3 This is a schematic diagram of the internal structure of the flue gas heat exchanger of the present utility model;

[0022] Figure 4 This is a schematic diagram of the heat exchange plate structure of the present utility model;

[0023] In the figure: 1. Gas hot water boiler; 2. Natural gas pipeline; 3. Direct-fired heat pump; 4. Flue gas conveying pipe; 5. Flue gas heat exchanger; 6. Medium water heat exchange pipeline; 7. Flue gas exhaust pipe; 8. Fan; 9. Chimney; 10. Heating network water supply pipeline; 11. Heating network return pipeline; 12. Heat exchange heating section; 13. Flue gas filter; 14. Flue gas inlet and outlet; 15. Water inlet pipe; 16. Drain pipe; 17. Heat exchange plate; 18. Heat exchange diverter; 19. Connecting pipe groove; 20. Heat exchange pipe groove; 21. Connecting port; 22. Heat exchange component. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0025] See also Figure 2 、 Figure 3 、 Figure 4The utility model provides an embodiment: a flue gas waste heat recovery device, comprising: a flue gas heat exchanger 5, a flue gas inlet and outlet 14 are provided at both the front and rear ends of the flue gas heat exchanger 5, a heat exchange component 22 is provided inside the flue gas heat exchanger 5, the heat exchange component 22 comprises a plurality of vertically spaced heat exchange plates 17, a heat exchange diversion channel 18 is provided between the heat exchange plates 17, a heat exchange pipe groove 20 for installing a heat exchange pipe is provided on the outer walls of the upper and lower ends of the heat exchange plate 17, a connecting port 21 for connecting the upper and lower surface heat exchangers is provided at one end of the heat exchange pipe groove 20, a connecting pipe groove 19 for connecting heat exchange pipes of different layers is provided on the inner wall of the flue gas heat exchanger 5; The heat assembly 22 is provided to recover the waste heat of the flue gas through heat exchange. The high-temperature flue gas enters the flue gas heat exchanger 5 from the flue gas inlet and outlet 14. The flue gas is diverted and dispersed at the heat exchange plates 17 of each layer, so that the flue gas enters the heat exchange diversion channel 18 between the upper and lower heat exchange plates 17 and is affected by the heat exchange of the media from the upper and lower layers. The connecting port 21 can connect the heat exchange pipes on the upper and lower surfaces of the same heat exchange plate 17. The heat exchange pipes on the heat exchange plates 17 of different layers can be connected through the connecting pipe groove 19, so that the heat exchange pipes can be densely distributed on the surface of the heat exchange plates 17 of each layer from top to bottom, which can effectively increase the heat exchange area and improve the heat exchange efficiency.

[0026] The heat exchange plate 17 is made of aluminum, and the heat exchange tube groove 20 is in the shape of a coil. Aluminum has good heat conductivity and can transfer heat to the heat exchange tube. The heat exchange tube is a common copper tube in the field. The coil shape can extend the internal medium residence time and increase the coverage area of ​​the heat exchange tube on the heat exchange plate 17, thereby increasing the heat exchange area.

[0027] A water inlet 15 is provided on the side wall of the flue gas heat exchanger 5 for connecting to the end of the uppermost heat exchange plate 17. A drain outlet 16 is provided below the water inlet 15 for connecting to the end of the lowermost heat exchange plate 17. One end of each of the water inlet 15 and the drain outlet 16 is provided with a medium water heat exchange pipeline 6. A direct-fired heat pump 3 is provided at the end of the medium water heat exchange pipeline 6 away from the flue gas heat exchanger 5.

[0028] When the flue gas circulates, it is always in contact with the heat exchange tubes located on the heat exchange tube groove 20. The heat exchange tubes are filled with heat exchange medium water, which gradually cools down the flue gas and gradually heats up the medium water. Finally, the flue gas is discharged from the other end, and the medium water is heated and transported to the direct-fired heat pump 3 through the medium water heat exchange pipeline 6. The heat is transferred to the heat network return water pipeline 11, forming waste heat recovery. The heat network return water temperature increases, and then enters the boiler system to be heated to the heat network design temperature and is sent to the heat network water supply pipeline 10 for heating circulation.

[0029] See also Figure 1The inlet end of the direct-fired heat pump 3 is connected to the natural gas pipeline 2, and one end of the direct-fired heat pump 3 is connected to the flue gas conveying pipe 4 through the flue gas pipeline. A flue gas filter 13 is provided between the flue gas conveying pipe 4 and the flue gas pipeline. The outlet end of the flue gas heat exchanger 5 is provided with a flue gas exhaust pipe 7, and one end of the flue gas exhaust pipe 7 is provided with a chimney 9. A fan 8 is provided at the front end of the chimney 9;

[0030] The flue gas filter 13 is used to filter the flue gas at the flue gas conveying pipe 4 and the flue gas pipeline. The filtered gas then enters the flue gas heat exchanger 5 for heat exchange operation. After the heat exchange, the flue gas is pulled by the fan 8 to enter the chimney 9 along the flue gas exhaust pipe 7 and be discharged.

[0031] See also Figure 1 A flue gas conveying pipe 4 is provided at the inlet end of the flue gas heat exchanger 5, a gas hot water boiler 1 is provided at one end of the flue gas conveying pipe 4, a natural gas pipeline 2 is provided at the inlet end of the gas hot water boiler 1, a heat network water supply pipeline 10 is provided at the outlet end of the gas hot water boiler 1, and a heat network return water pipeline 11 is provided at the other inlet end of the gas hot water boiler 1. One end of the heat network return water pipeline 11 is connected to the direct-fired heat pump 3 through a heat exchange and heating section 12, and the absorption heat pump technology is used to absorb the heat of the intermediate medium and convert it into low-temperature hot water. The heat network return water is initially heated and then enters the original boiler system to further heat the heat network return water to the temperature required by the external network for external heat supply.

[0032] Working principle: When in use, the heat exchange component 22 is set to recover the waste heat of the flue gas. Among them, the high-temperature flue gas enters the flue gas heat exchanger 5 from the flue gas inlet and outlet 14. The flue gas is diverted and dispersed at the heat exchange plates 17 of each layer, so that the flue gas enters the heat exchange diversion channel 18 between the upper and lower heat exchange plates 17. It is affected by the heat exchange of the media from the upper and lower layers. The connecting port 21 can connect the heat exchange pipes on the upper and lower surfaces of the same heat exchange plate 17. The heat exchange pipes at the heat exchange plates 17 of different layers can be connected through the connecting pipe groove 19, so that the heat exchange pipes can be densely distributed from top to bottom. The surface of the heat exchange plates 17 at each level can effectively increase the heat exchange area and improve the heat exchange efficiency. When the flue gas circulates, it is always in contact with the heat exchange tubes located on the heat exchange tube grooves 20. The heat exchange tubes are filled with heat exchange medium water, which gradually cools down the flue gas and gradually heats up the medium water. Finally, the flue gas is discharged from the other end, and the medium water is heated and transported to the direct-fired heat pump 3 through the medium water heat exchange pipeline 6. The heat is transferred to the heat network return water pipeline 11, forming waste heat recovery. The heat network return water temperature increases, and then enters the boiler system to be heated to the heat network design temperature and then sent to the heat network water supply pipeline 10 for heating cycle.

[0033] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be encompassed within the present invention. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. A flue gas waste heat recovery device, comprising a flue gas heat exchanger (5), characterized in that: The flue gas heat exchanger (5) is provided with a flue gas inlet and outlet (14) at both the front and rear ends. A heat exchange assembly (22) is provided inside the flue gas heat exchanger (5). The heat exchange assembly (22) includes a plurality of heat exchange plates (17) arranged vertically at intervals. Heat exchange diversion channels (18) are provided between the heat exchange plates (17). Heat exchange pipe grooves (20) for installing heat exchange pipes are provided on the outer walls of the upper and lower ends of the heat exchange plates (17). A connecting port (21) for connecting the upper and lower surface heat exchangers is provided at one end of the heat exchange pipe groove (20). A connecting pipe groove (19) for connecting heat exchange pipes at different levels is provided on the inner wall of the flue gas heat exchanger (5).

2. The flue gas waste heat recovery device according to claim 1, characterized in that: A water inlet (15) for connecting to the end of the uppermost heat exchange plate (17) is provided on the side wall of the flue gas heat exchanger (5), and a drain pipe (16) for connecting to the end of the lowermost heat exchange plate (17) is provided below the water inlet (15).

3. The flue gas waste heat recovery device according to claim 2, characterized in that: One end of each of the water inlet pipe (15) and the drain pipe (16) is provided with a medium water heat exchange pipeline (6), and one end of the medium water heat exchange pipeline (6) away from the flue gas heat exchanger (5) is provided with a direct-fired heat pump (3).

4. The flue gas waste heat recovery device according to claim 3, characterized in that: The inlet end of the direct-fired heat pump (3) is in communication with the natural gas pipeline (2), and one end of the direct-fired heat pump (3) is in communication with the flue gas delivery pipe (4) via a flue gas pipeline.

5. The flue gas waste heat recovery device according to claim 4, characterized in that: A smoke filter (13) is provided between the smoke conveying pipe (4) and the smoke pipeline.

6. The flue gas waste heat recovery device according to claim 1, characterized in that: The outlet end of the flue gas heat exchanger (5) is provided with a flue gas exhaust pipe (7), one end of the flue gas exhaust pipe (7) is provided with a chimney (9), and the front end of the chimney (9) is provided with a fan (8).

7. The flue gas waste heat recovery device according to claim 1, characterized in that: A flue gas conveying pipe (4) is provided at the inlet end of the flue gas heat exchanger (5), a gas hot water boiler (1) is provided at one end of the flue gas conveying pipe (4), and a natural gas pipeline (2) is provided at the inlet end of the gas hot water boiler (1).

8. The flue gas waste heat recovery device according to claim 7, characterized in that: A heat network water supply pipeline (10) is provided at the outlet end of the gas hot water boiler (1).

9. The flue gas waste heat recovery device according to claim 7, characterized in that: A heat network return pipe (11) is provided at the other inlet end of the gas hot water boiler (1), and one end of the heat network return pipe (11) is connected to a direct-fired heat pump (3) via a heat exchange and temperature-raising section (12).

10. The flue gas waste heat recovery device according to claim 1, characterized in that: The heat exchange plate (17) is made of aluminum, and the heat exchange tube groove (20) is in the shape of a coiled tube.

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