Waste heat recovery system for drying

Abstract

The utility model provides a waste heat recovery system for drying, which relates to the technical field of drying equipment and comprises a drying chamber, a boiler, a heat exchanger and a flue gas waste heat recovery component, a moisture removal pipeline is arranged at the top of the drying chamber, and the heat exchanger is connected with a fresh air pipeline and the moisture removal pipeline. Gas conveyed by the fresh air pipeline can be preheated through the heat exchanger, and the heat exchanger further communicates with a boiler so that the preheated gas can be fed into the boiler to be heated; the flue gas waste heat recovery assembly comprises a waste heat recovery pipe body communicated with a flue gas pipeline of the boiler, the waste heat recovery pipe body is provided with a fresh air inlet, a flue gas inlet and a fresh air outlet, and a heat exchange flowing channel is arranged in the waste heat recovery pipe body so that gas passing through the fresh air inlet can be preheated; the fresh air outlet is communicated with the boiler through a pipeline, so that preheated gas can be fed into the boiler to be heated; the boiler communicates with the drying chamber so that heated gas in the boiler can be conveyed into the drying chamber.

Description

Technical Field

[0001] The utility model relates to the technical field of drying equipment, and in particular to a waste heat recovery system for drying. Background Art

[0002] In the process of drying materials, the materials continuously absorb heat, evaporate the internal moisture into the air in the drying chamber, and then discharge it to the outside of the equipment through the dehumidification system. The materials are dried in this cycle. However, most of the heat will be taken away in the dehumidification process, resulting in excessive energy consumption. If dehumidification is not performed, the gas in the drying chamber will absorb the humid and hot water vapor, so that the water content of the gas in the drying chamber as a whole is high and the temperature is reduced, which is not conducive to drying and affects the drying efficiency. At the same time, it will further increase the energy consumption investment and increase its cost. Therefore, it is urgent to reduce energy consumption while ensuring dehumidification. In addition, the boiler needs to continuously transport high-temperature gas to the drying chamber for drying. At this time, more flue gas with higher temperature will be generated, which is waste gas. If the flue gas is directly discharged after dust removal, it is not conducive to environmental protection and wastes energy. Utility Model Content

[0003] The purpose of the utility model is to provide a waste heat recovery system for drying, so as to realize the effective use of the moist and hot gas discharged in the drying chamber to preheat the unheated new air. In addition, it is also combined with the high-temperature flue gas of the boiler to preheat the unheated new air, and the preheated gas is sent into the boiler again to be heated to a specified temperature. Through this solution, resources can be effectively utilized, energy waste can be reduced, and technical effects such as energy consumption can be reduced.

[0004] The utility model is realized by the following technical scheme: comprising a drying chamber, a boiler, a heat exchanger, and a flue gas waste heat recovery component, wherein a dehumidification pipeline is arranged on the top of the drying chamber, the heat exchanger is connected with a new air pipeline and a dehumidification pipeline, and the gas transported by the new air pipeline can be preheated by the heat exchanger, and the heat exchanger is also connected with the boiler so that the preheated gas is sent into the boiler for heating;

[0005] The flue gas waste heat recovery assembly comprises a waste heat recovery pipe body connected to the flue gas pipeline of the boiler, the waste heat recovery pipe body is provided with a new air inlet, a flue gas inlet and a new air outlet, a heat exchange flow passage is provided in the waste heat recovery pipe body, so that the gas input into the waste heat recovery pipe body from the new air inlet can be preheated, and the new air outlet is connected to the boiler through a pipeline, so that the preheated gas can be sent into the boiler for heating;

[0006] The boiler is communicated with the drying chamber so that the gas heated in the boiler is transported into the drying chamber.

[0007] In order to better realize the utility model, it further includes an air supply fan, the air inlet of which is respectively connected to the heat exchanger and the waste heat recovery pipe body, so that the gas preheated by the heat exchanger and the gas preheated by the waste heat recovery pipe body are input into the boiler.

[0008] In order to better realize the utility model, further, the waste heat recovery pipe body includes an inner tube and an outer tube arranged outside the inner tube, and a partition tube is also arranged in the cavity formed between the inner tube and the outer tube to divide the cavity into a first heat exchange flow channel and a second heat exchange flow channel, and new air circulates in the first heat exchange flow channel and the second heat exchange flow channel.

[0009] In order to better realize the utility model, further, the first heat exchange flow passage is close to the outer tube, the second heat exchange flow passage is close to the inner tube, and the new air inlet is arranged at one end of the outer tube to communicate with the first heat exchange flow passage;

[0010] The new air outlet is arranged at one end of the partition tube so as to communicate with the second heat exchange flow passage. The new air outlet is connected to an outward output pipe, and the free end of the outward output pipe can extend out of the outer pipe.

[0011] In order to better realize the utility model, further, the fresh air inlet, the fresh air outlet and the smoke inlet are all arranged at the same end of the waste heat recovery pipe body.

[0012] In order to better realize the present utility model, further, a plurality of heat exchange fins are arranged in both the first heat exchange flow passage and the second heat exchange flow passage.

[0013] In order to better realize the present utility model, further, the heat exchange fins in the first heat exchange flow channel and the heat exchange fins in the second heat exchange flow channel are installed alternately.

[0014] The beneficial effects of the utility model are:

[0015] The utility model can convert the heat of the hot and humid gas in the drying room through the action of the heat exchanger, so that the temperature of the hot and humid gas is reduced, and the temperature of the new air is preheated and increased. The flue gas generated by the boiler is recovered through the flue gas waste heat recovery component, so that the temperature of the flue gas to be discharged is reduced, and the temperature of the new air is preheated and increased. The preheated gases of both are transported to the boiler again for heating to reach the set temperature, and then are input into the drying room again after reaching the set temperature. The device structure can make full use of waste gas resources, reduce energy waste, and at the same time can reduce energy consumption and save costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solution of the present invention, the following is a brief introduction to the drawings required for use in the present invention. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 A schematic diagram of the structure of a waste heat recovery system for drying provided by the utility model;

[0018] Figure 2 A partial structural schematic diagram of a waste heat recovery system for drying provided by the utility model;

[0019] Figure 3 The structure diagram of the flue gas waste heat recovery component provided by the utility model Figure 1 ;

[0020] Figure 4 The structure diagram of the flue gas waste heat recovery component provided by the utility model Figure 2 ;

[0021] Figure 5 for Figure 4 Sectional view in the AA direction;

[0022] Figure 6 for Figure 4 Cross-sectional view in the BB direction;

[0023] icon:

[0024] 10-drying chamber, 11-dehumidification pipe, 20-boiler, 21-flue gas pipe, 30-heat exchanger, 40-flue gas waste heat recovery component, 41-waste heat recovery pipe body, 42-new air inlet, 43-flue gas inlet, 44-new air outlet, 45-inner pipe, 46-outer pipe, 47-partition tube, 48-first heat exchange flow channel, 49-second heat exchange flow channel, 491-heat exchange fins, 50-air supply fan. DETAILED DESCRIPTION

[0025] The technical solution of the present invention will be described below in conjunction with the accompanying drawings of the present invention.

[0026] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of the present utility model, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0027] Please see Figures 1 to 6 The utility model provides a waste heat recovery system for drying. The prior art requires that the hot and humid gas in the drying chamber 10 be discharged to the outside. The hot and humid gas has a certain temperature, and direct discharge results in heat waste. In addition, the boiler 20 needs to be continuously heated to increase the temperature of the gas. The heating of the boiler 20 will produce flue gas (i.e., waste gas), which can also be directly discharged after the flue gas is dusted. The temperature of the flue gas is also relatively high, and direct discharge also results in heat waste and is not environmentally friendly. In order to solve the above technical problems, the utility model sets up a waste heat recovery system to reasonably collect waste heat, and through the conversion of waste heat, enables it to heat new air, so as to achieve the purpose of rational use of resources and reduce energy consumption.

[0028] As shown in the figure, the waste heat recovery system for drying provided by the utility model mainly includes a drying chamber 10, a boiler 20, a heat exchanger 30, and a flue gas waste heat recovery component 40, wherein the drying chamber 10 is used for drying, such as conventional materials such as peppers that need to be dried, and the boiler 20 is used to provide high-temperature gas to the drying chamber 10. During the process of drying the materials in the drying chamber 10, the moisture is gradually evaporated and retained in the drying chamber 10. In order to avoid the influence of humid hot gas on the drying efficiency, a dehumidification pipe 11 is set at the top of the drying chamber 10 to discharge the humid hot gas. In order to reasonably utilize resources and reduce the waste of heat from humid hot gas, the other end of the dehumidification pipe 11 is connected to the heat exchanger 30. Next, the heat exchanger 30 can be a conventional one. A high-temperature circulation channel and a low-temperature circulation channel are set in the heat exchanger 30, and a heat exchange plate is set in the heat exchanger 30. Under the action of the heat exchange plate, the gas flowing in the low-temperature circulation channel can absorb the heat of the high-temperature circulation channel to achieve heat conversion. The humid and hot gas discharged from the dehumidification channel flows to the high-temperature circulation channel in the heat exchanger 30. The entrance end of the low-temperature circulation channel is connected to the new air duct. Under the action of the heat exchanger 30, the new air is preheated, thereby achieving the purpose of rational use of resources. The preheated new air is then transferred to the boiler 20 for heating and temperature rise. After heating in the boiler 20, it enters the drying chamber 10 again to dry the material.

[0029] During the process of adding gas to the boiler 20, flue gas will be continuously generated, and its flue gas duct 21 can be subjected to dust reduction treatment. In order to reasonably utilize the high temperature of the flue gas, a waste heat recovery pipe body 41 is further connected to the end of the flue gas duct 21. The waste heat recovery pipe body 41 includes an inner pipe 45 and an outer pipe 46. A partition 47 is arranged in the cavity between the inner pipe 45 and the outer pipe 46. A gap is left between one end of the partition 47 and the top of the outer pipe 46 so that the gas can flow. Under the action of the heat exchanger, the cavity is divided into a first heat exchange flow passage 48 and a second heat exchange flow passage 49, wherein the first heat exchange flow passage 48 is close to the outer tube 46, and the second heat exchange flow passage 49 is close to the inner tube 45, and a new air inlet 42 is provided at the end of the outer tube 46, and a new air outlet 44 is provided on the partition 47, and the new air outlet 44 is connected to an external output pipe so that the heat exchanged gas can be output through the external output pipe, and the end of the inner tube 45 is connected to the smoke inlet 43, as shown in FIG. Figure 5 As shown, the fresh air inlet 42, the fresh air outlet 44 and the flue gas inlet 43 are all located at the same end, which is conducive to more complete heat conversion. During use, the flue gas duct 21 is connected to the flue gas inlet 43, and the generated flue gas circulates in the inner tube 45. The fresh air flows from the fresh air inlet 42 to the first heat exchange flow channel 48, and then flows to the second heat exchange flow channel 49. By setting the double-layer heat exchange flow channel, the flue gas can be more fully heat exchanged so that its heat can be fully converted. After the heat exchange is accepted, the low-temperature flue gas is discharged from the other end of the inner tube 45, and the preheated new air is discharged from the fresh air outlet 44 through the external output pipe. The external output pipe can be connected to the boiler 20 so that the preheated new air is input into the boiler 20 for heating.

[0030] In order to achieve a more efficient heat exchange effect when using the first heat exchange flow channel 48 and the second heat exchange flow channel 49, heat exchange fins 491 are also provided in the first heat exchange flow channel 48 and the second heat exchange flow channel 49. As shown in the figure, the heat exchange fins 491 in the first heat exchange flow channel 48 and the heat exchange fins 491 in the second heat exchange flow channel 49 are installed alternately.

[0031] When the heat exchanger 30 and the flue gas waste heat recovery component 40 are used in combination, in order to save more resources and reduce the occupied space, an air supply fan 50 is also provided. As shown in the figure, the air inlet of the air supply fan 50 is respectively connected to the heat exchanger 30 and the waste heat recovery pipe body 41. Specifically, after the new air of the heat exchanger 30 is heat-exchanged, it is connected to the air inlet of the air supply fan 50 through a pipeline, and the outward output pipe of the flue gas waste heat recovery component 40 is connected to the air inlet of the air supply fan 50. Under the action of the air supply fan 50, they are jointly input into the boiler 20.

[0032] The utility model can convert the heat of the hot and humid gas in the drying chamber 10 through the action of the heat exchanger 30, so that the temperature of the hot and humid gas is reduced, and the temperature of the new air is preheated and increased. The flue gas generated by the boiler 20 is passed through the flue gas waste heat recovery component 40, so that the temperature of the flue gas to be discharged is reduced, and the temperature of the new air is preheated and increased. The preheated gases of both are transported to the boiler 20 again for heating to reach the set temperature. After reaching the set temperature, they are input into the drying chamber 10 again. The structure of the device can make full use of waste gas resources, reduce energy waste, and at the same time can reduce energy consumption and save costs.

[0033] The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the utility model, which should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. A waste heat recovery system for drying, characterized in that: The invention comprises a drying chamber (10), a boiler (20), a heat exchanger (30), and a flue gas waste heat recovery component (40); a dehumidification pipe (11) is arranged on the top of the drying chamber (10); the heat exchanger (30) is connected to a new air pipe and the dehumidification pipe (11); the heat exchanger (30) can preheat the gas transported by the new air pipe; the heat exchanger (30) is also connected to the boiler (20) so that the preheated gas is transported to the boiler (20) for heating; The flue gas waste heat recovery component (40) comprises a waste heat recovery pipe body (41) connected to the flue gas duct (21) of the boiler (20); the waste heat recovery pipe body (41) is provided with a fresh air inlet (42), a flue gas inlet (43) and a fresh air outlet (44); a heat exchange flow passage is provided in the waste heat recovery pipe body (41) so that the gas input into the waste heat recovery pipe body (41) from the fresh air inlet (42) can be preheated; the fresh air outlet (44) is connected to the boiler (20) through a pipeline so that the preheated gas can be sent into the boiler (20) for heating; The boiler (20) is in communication with the drying chamber (10) so that the gas heated in the boiler (20) is transported into the drying chamber (10).

2. The waste heat recovery system for drying according to claim 1, characterized in that: It also includes an air supply fan (50), the air inlet of which is respectively connected to the heat exchanger (30) and the waste heat recovery pipe body (41), so as to input the gas preheated by the heat exchanger (30) and the gas preheated by the waste heat recovery pipe body (41) into the boiler (20).

3. The waste heat recovery system for drying according to claim 2, characterized in that: The waste heat recovery pipe body (41) includes an inner pipe (45) and an outer pipe (46) arranged outside the inner pipe (45), and a partition tube (47) is also arranged in the cavity formed between the inner pipe (45) and the outer pipe (46) to divide the cavity into a first heat exchange flow channel (48) and a second heat exchange flow channel (49), and new air circulates in the first heat exchange flow channel (48) and the second heat exchange flow channel (49).

4. The waste heat recovery system for drying according to claim 3, characterized in that: The first heat exchange flow passage (48) is close to the outer tube (46), the second heat exchange flow passage (49) is close to the inner tube (45), and the new air inlet (42) is arranged at one end of the outer tube (46) so as to communicate with the first heat exchange flow passage (48); The new air outlet (44) is arranged at one end of the partition tube (47) to communicate with the second heat exchange flow passage (49). The new air outlet (44) is connected to an outward output pipe, and the free end of the outward output pipe can extend out of the outer pipe (46).

5. The waste heat recovery system for drying according to claim 4, characterized in that: The fresh air inlet (42), the fresh air outlet (44) and the smoke inlet (43) are all arranged at the same end of the waste heat recovery pipe body (41).

6. The waste heat recovery system for drying according to claim 3, characterized in that: A plurality of heat exchange fins (491) are disposed in the first heat exchange flow passage (48) and the second heat exchange flow passage (49).

7. The waste heat recovery system for drying according to claim 6, characterized in that: The heat exchange fins (491) in the first heat exchange flow passage (48) and the heat exchange fins (491) in the second heat exchange flow passage (49) are installed alternately.

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