CN117553584A - Flue gas waste heat utilization device and rotary kiln - Google Patents

Abstract

The invention belongs to the technical field of flue gas waste heat utilization, and specifically discloses a flue gas waste heat utilization device and a rotary kiln. The flue gas waste heat utilization device includes an evaporator, a condensation pipe and a shell; the evaporator is connected to the flue gas outlet end of external equipment. Deionized water is placed inside; the condensation pipe is set inside the shell and is connected to the evaporator through the steam channel and the condensation channel; the shell is provided with an air inlet end and an air outlet end; the air inlet end is connected to an air supply device, and the air outlet The terminal is connected to the preheating channel of external equipment. The rotary kiln is used for waste heat treatment, and the flue gas heat discharged from the rotary kiln is utilized based on the flue gas waste heat utilization device. The flue gas waste heat utilization device realizes effective recovery and utilization of the heat carried by the flue gas. It uses the flow guide assembly to force the flue gas to flow closer to the inner wall, forming an inner ring for the flow of flue gas. In addition, the flow guide assembly reduces the flow cross section. , the flue gas flow rate will also increase, thereby causing the Reynolds number to increase and the heat transfer effect between the flue gas and the evaporator to be better.

Description

Flue gas waste heat utilization device and rotary kiln

Technical field

The invention belongs to the technical field of flue gas waste heat utilization, and particularly relates to a flue gas waste heat utilization device and a rotary kiln.

Background technique

Thermal treatment can recycle a large amount of waste in a short period of time. The toxic and harmful substances in the waste are oxidized and pyrolyzed at high temperatures to achieve maximum harmlessness. Heat treatment is one of the most effective methods for treating waste.

Rotary kilns are not only widely used in process industries such as cement production, but also in the energy field. The advantage of using a rotary kiln in garbage is that it can handle any waste, including industrial waste and biomass waste; and the rotary kiln can withstand higher temperatures, about 1400°C. At such high temperatures, harmful components in the garbage are eliminated and substances are completely decomposed; in addition, the rotary kiln equipment barrel is long, the garbage lasts for a long time in the high temperature state of the rotary kiln, and the combustion and classification of garbage are also utilized. Rotary kiln has become the best choice for thermal treatment of garbage and waste.

When the rotary kiln thermally treats garbage, the flue gas emitted from the tail has high heat, accounting for about 18.95% of the input energy, and is the main source of heat loss in the rotary kiln garbage system. If the higher-temperature flue gas at the tail is directly discharged into the atmosphere, This will lead to insufficient recycling and serious waste of energy.

Contents of the invention

In view of the above-mentioned existing problems, the purpose of the present invention is to provide a flue gas waste heat utilization device and a rotary kiln, which can effectively recycle and utilize the higher heat of higher-temperature flue gas, and effectively avoid the problem of energy waste.

The technical solution of the present invention is: a flue gas waste heat utilization device, including:

The evaporator is used to communicate with the flue gas outlet end of the external equipment; the evaporator has a tubular structure, and the side wall of the evaporator is provided with a hollow cavity, and deionized water is placed inside the hollow cavity. The water exchanges heat with the flue gas through the side wall of the evaporator and then evaporates into water vapor;

The heat exchange component includes a shell. A condensation pipe is provided in the shell. Both ends of the condensation pipe are respectively connected with the hollow cavity. One end is used for the inflow of water vapor, and the other end is used for the water vapor to flow out after liquefaction. ; The housing is also provided with an air inlet end and an air outlet end. The air inlet end is used to communicate with the outlet of the air supply device. The air outlet end is used to communicate with the air inlet of external equipment. The air supply device is used to introduce air into the interior of the housing, so that the air flows from the air outlet end into the air inlet of the external device after heat exchange with the condensation pipe.

Further, the hollow cavity divides the side wall of the evaporator into an inner wall and an outer wall;

Both ends of the condensation pipe are connected to the hollow cavity through a steam channel and a condensation channel respectively; and the steam channel and the condensation channel both penetrate the outer wall and are connected to the hollow cavity; the steam channel and the condensation channel are connected to the hollow cavity. The channels all penetrate the outer wall and communicate with the hollow cavity.

Furthermore, a flow guide assembly is provided in the inner wall, and the flow guide assembly is used to guide the flue gas to flow close to the inner wall; the flow guide assembly includes a flow guide column and a mounting rod; One end is provided on the upper end of the side wall of the guide column, and the other end is provided on the inner wall; the guide column is coaxial with the evaporator, and the bottom of the guide column is flush with the bottom of the evaporator, The top of the guide column is lower than the top of the evaporator.

Furthermore, a distribution pipe is provided inside the hollow cavity; the distribution pipe is a coil spring structure, and a plurality of leakage holes are spaced on the lower side of the distribution pipe; the distribution pipe is located in the hollow The upper end of the interior of the cavity; the condensation channel extends through the outer wall and into the hollow cavity, and is connected to the higher end port of the distribution pipe.

Furthermore, the air guide assembly further includes a first air guide plate. The first air guide plate is a funnel-shaped structure. There are multiple first air guide plates, and they are spaced apart from bottom to top on the air guide plate. on the side wall of the stream column.

Furthermore, the air guide assembly further includes a second air guide plate, the second air guide plate has a spiral structure, and the inner side of the second air guide plate is spirally arranged on the side wall of the air guide column, And the outside is in contact with the inner wall.

Furthermore, the inner wall and the guide column form a smoke exhaust annular cavity, and a partition plate is provided on the inner wall. There are multiple partition plates and they are distributed at circumferential intervals on the smoke exhaust annular cavity.

Further, the horizontal height of the inlet end of the condensation pipe is higher than the horizontal height of the connecting end of the hollow cavity and the steam channel;

The level of the outlet end of the condensation pipe is higher than the level of the connection end of the distribution pipe and the condensation channel.

A rotary kiln, used for heat treatment of garbage, has a kiln head and a kiln tail. The kiln head is provided with an air preheating channel, and the connection is provided with a first sealing mechanism; the kiln tail is provided with a smoke chamber, and the connection is provided with a a second sealing mechanism; a flue is provided on the smoke chamber; it also includes the flue gas waste heat utilization device, the evaporator is connected to the flue, and the air preheating channel is connected to the air outlet. .

Furthermore, the flue is a tubular structure, and the evaporator is welded on the flue.

The working principle of this embodiment is: when the flue gas flows through the evaporator, it flows along the inner wall under the action of the guide assembly. At this time, deionized water is placed inside the hollow cavity to heat it until the deionized water reaches The boiling point turns into water vapor and flows into the condensation pipe through the steam channel. The air supply device guides the wind to the inside of the shell to cool the water vapor and achieve heat exchange. External equipment can be connected from the air outlet end to utilize the hot air. After the water vapor is cooled into a liquid state, it flows from the condensation channel to the distribution pipe, and further flows evenly into the hollow cavity to complete the circulation of the working fluid.

Compared with the existing technology, the beneficial effect of the present invention is that the proposed flue gas waste heat utilization device realizes effective recovery and utilization of the heat carried by the flue gas. Among them, the flue gas directly passes through the evaporator with a tubular structure. The internal flow guide assembly forces the flue gas to flow closer to the inner wall, forming an inner ring for the flue gas flow. In addition, the flow guide assembly reduces the flow cross-section and the flue gas flow rate will also be Increase, thereby causing the Reynolds number to increase, and the heat transfer effect between the flue gas and the evaporator is better. The proposed rotary kiln based flue gas waste heat utilization device can fully recover the heat in the flue gas discharged from the rotary kiln itself, effectively improving energy utilization.

Description of the drawings

Figure 1 is a schematic structural diagram of the flue gas waste heat utilization device of the present invention;

Figure 2 is a schematic structural diagram of an evaporator in Embodiment 1 of the present invention;

Figure 3 is a cross-sectional view of the evaporator of the present invention;

Figure 4 is a schematic structural diagram of the distribution pipeline of the present invention;

Figure 5 is a schematic structural diagram of the evaporator in Embodiment 2 of the present invention;

Figure 6 is a schematic structural diagram of an evaporator in Embodiment 3 of the present invention;

Figure 7 is a schematic structural diagram of the evaporator in Embodiment 4 of the present invention.

Figure 8 is a schematic structural diagram of an evaporator in Embodiment 5 of the present invention;

Figure 9 is a schematic structural diagram of the rotary kiln of the present invention.

Among them, 1-evaporator, 10-hollow cavity, 100-smoke exhaust ring cavity, 11-inner wall, 110-partition plate, 12-and outer wall, 13-distribution pipe, 130-leak hole, 2-condensation pipe , 3-shell, 30-air supply device, 41-steam channel, 42-condensation channel, 5-guide assembly, 51-guide column, 52-installation rod, 53-first guide plate, 54-No. Two baffles, 61-air preheating channel, 62-smoke chamber, 620-flue.

Detailed ways

Specific embodiments of the present invention will be described in detail below with reference to Figures 1 to 9. In the description of the present invention, it should be understood that the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", The orientations or positional relationships indicated by "top", "bottom", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply. The devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation and therefore are not to be construed as limitations of the invention.

The terms “first” and “second” are used for descriptive purposes only and shall not be understood as indicating or implying relative importance or implicitly indicating the quantity of indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features; in the description of the present invention, unless otherwise stated, the meaning of "plurality" is Two or more.

Example 1

The flue gas waste heat utilization device shown in Figure 1 includes an evaporator 1 and a heat exchange component.

The evaporator 1 is used to communicate with the flue gas outlet end of the external equipment; the evaporator 1 has a tubular structure, and the side wall of the evaporator 1 is provided with a hollow cavity 10, and deionized water is placed inside the hollow cavity 10, and the deionized water passes through The side wall of the evaporator 1 exchanges heat with the flue gas and then evaporates into water vapor. The evaporator 1 is made of stainless steel, which is in direct contact with the flue gas. Stainless steel has good corrosion resistance and can withstand large pressure differences and thermal stress. The use of stainless steel can reduce damage to the evaporator 1 and ensure reliable operation.

The heat exchange component includes a shell 3. A condensation pipe 2 is provided in the shell 3. Both ends of the condensation pipe 2 are respectively connected with the hollow cavity 10. One end is used for the inflow of water vapor, and the other end is used for the water vapor to flow out after liquefaction. ; The housing 3 is also provided with an air inlet end and an air outlet end. The air inlet end is used to communicate with the outlet of the air supply device 30. The air outlet end is used to communicate with the air inlet of the external equipment. The air supply device 30 is used to communicate with the air inlet of the external equipment. Air is introduced into the housing 3 so that the air exchanges heat with the condensation pipe 2 and then flows from the air outlet end into the air inlet of the external device. Among them, the condensation pipe 2 is provided with fins, which not only increase the surface area of the heat exchanger, but also increase the heat transfer coefficient by promoting turbulence and destroying the boundary layer, thereby improving the heat transfer efficiency. The condensation pipe 2 is made of metallic copper. Metal copper has excellent thermal conductivity and can effectively dissipate heat, contributing to efficient heat transfer from water vapor to air. The air supply device 30 adopts a commercially available fan.

Preferably, the hollow cavity 10 divides the side wall of the evaporator 1 into an inner wall 11 and an outer wall 12 . Both ends of the condensation pipe 2 are connected to the hollow cavity 10 through the steam channel 41 and the condensation channel 42 respectively; and the steam channel 41 and the condensation channel 42 both penetrate the outer wall 12 and are connected to the hollow cavity 10 .

Preferably, the inner wall 11 is provided with a flow guide assembly 5 , and the flow guide assembly 5 is used to guide the flue gas to flow close to the inner wall 11 . The flow guide assembly 5 includes a flow guide column 51 and a mounting rod 52; one end of the installation rod 52 is disposed on the upper end of the side wall of the flow guide column 51, and the other end is disposed on the inner wall 11; the flow guide column 51 is coaxial with the evaporator 1. And the bottom of the guide column 51 is flush with the bottom of the evaporator 1, and the top of the guide column 51 is lower than the top of the evaporator 1. The guide column 51 is used to force the flue gas to flow closer to the inner wall 11, bypassing the central axis of the evaporator 1, so that the flue gas flows to form an inner ring. In addition, the guide column 51 reduces the flow cross-section and the flue gas flow rate will also increase. , the Reynolds number increases, and the heat transfer effect between the flue gas and the inner wall 11 is better. The guide column 51 is used to force the flue gas to flow closer to the inner wall 11, bypassing the central axis of the evaporator 1, so that the flue gas flows to form an inner ring. In addition, the guide column 51 reduces the flow cross-section and the flue gas flow rate will also increase. , the Reynolds number increases, and the heat transfer effect between the flue gas and the inner wall 11 is better.

Preferably, a distribution pipe 13 is provided inside the hollow cavity 10; the distribution pipe 13 is a coil spring structure, and a plurality of leakage holes 130 are spaced on the lower side of the distribution pipe 13; the distribution pipe 13 is located at the upper end of the hollow cavity 10. ; The condensation channel 42 penetrates the outer wall 12 and then extends into the hollow cavity 10, and is connected to the higher end port of the distribution pipe 13. The axis center of the coil spring structure and the axis center of the hollow cavity 10 are located on the same straight line. The condensed deionized water is allowed to fall evenly from above in the hollow cavity 10 through the distribution pipe 13 . This allows deionized water and steam to circulate the working fluid without resorting to external power devices.

Preferably, the horizontal height of the inlet end of the condensation pipe 2 is higher than the horizontal height of the connecting end of the hollow cavity 10 and the steam channel 41 . The level of the outlet end of the condensation pipe 2 is higher than the level of the connection end of the distribution pipe 13 and the condensation channel 42 .

The working principle of this embodiment is: when the flue gas flows through the evaporator 1, it flows along the inner wall 11 under the action of the guide assembly 5. At this time, deionized water is placed inside the hollow cavity 10 to achieve heating. The deionized water reaches the boiling point and turns into water vapor. It flows into the condensation pipe 2 through the steam channel 41. The air supply device 30 guides the wind to the inside of the housing 3 to cool the water vapor and achieve heat exchange. It can be connected to the outside from the air outlet. The equipment realizes the utilization of hot air. After the water vapor is cooled into a liquid state, it flows from the condensation channel 42 to the distribution pipe 13, and further flows evenly into the hollow cavity 10, completing the circulation of the working fluid.

Example 2

The difference from Example 1 is:

Preferably, as shown in Figure 5, the air guide assembly 5 also includes a first air guide plate 53. The first air guide plate 53 is a funnel-shaped structure. There are multiple first air guide plates 53, and they are spaced apart from bottom to top. on the side wall of the guide column 51.

In actual use, the flow direction of the flue gas can be further auxiliary guided through the auxiliary flow guide, so that the flue gas can be closer to the inner wall 11 .

Example 3

The difference from Example 2 is:

Preferably, as shown in Figure 6, the inner wall 11 and the guide column 51 form the smoke exhaust ring cavity 100. The inner wall 11 is provided with partition plates 110. There are multiple partition plates 110, and they are distributed at circumferential intervals in the smoke exhaust ring. on cavity 100.

In actual use, the partition plate 110 is used to increase the contact area with the flue gas, thereby achieving a more complete recovery of the heat carried by the flue gas.

Example 4

What is different from Embodiment 1 is: preferably, as shown in Figure 7, the air guide assembly 5 also includes a second air guide plate 54. The second air guide plate 54 is a spiral structure, and the inner side of the second air guide plate 54 is spirally arranged. On the side wall of the flow guide column 51, and the outer side is in contact with the inner wall 11.

In actual use, the use of the second guide plate 54 with a spiral structure can effectively extend the time for the flue gas to pass through the smoke exhaust annular cavity 100, thereby fully recovering the heat carried by the flue gas.

Example 5

What is different from Embodiment 4 is that: as shown in Figure 8, the inner wall 11 and the flow guide column 51 form the smoke exhaust annular cavity 100, and the inner wall 11 is provided with partition plates 110. There are multiple partition plates 110, and they are circumferentially spaced. Distributed on the smoke exhaust ring cavity 100.

Example 6

The rotary kiln as shown in Figure 9 is used for waste heat treatment and has a kiln head and a kiln tail. The kiln head is provided with an air preheating channel 61, and a first sealing mechanism is provided at the connection; the kiln tail is provided with a smoke chamber 62, and the connection A second sealing mechanism is provided; a flue 620 is provided on the smoke chamber 62; it also includes a flue gas waste heat utilization device, the evaporator 1 is connected to the flue 620, and the air preheating channel 61 is connected to the air outlet.

Preferably, the flue 620 is a tubular structure, and the evaporator 1 is welded to the flue 620 . The evaporator 1, the flow guide assembly 5 and the flue 620 constitute a flue gas waste heat heat exchange area. The evaporator 1 is directly exposed to the untreated flue gas in the flue 620 to maximize the use of heat in the flue gas.

In actual use, the hot air at the air outlet end is introduced into the rotary kiln through the air preheating channel 61 to further utilize the heat source.

Preferably, the outsides of the flue 620, air preheating channel 61, steam channel 41 and condensation channel 42 are all provided with thermal insulation layers to prevent heat from being lost to the environment and save heat.

The above specific embodiments further describe the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific embodiments of the present invention and do not limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles are included in the protection scope of the present invention.

Claims (10)

1. Flue gas waste heat utilization device, which is characterized by including: The evaporator (1) is used to communicate with the flue gas outlet end of the external equipment; the evaporator (1) has a tubular structure, and the side wall of the evaporator (1) is provided with a hollow cavity (10). The hollow cavity Deionized water is placed inside the body (10), and the deionized water evaporates into water vapor after exchanging heat with the flue gas through the side wall of the evaporator (1); The heat exchange component includes a shell (3). A condensation pipe (2) is provided in the shell (3). Both ends of the condensation pipe (2) are connected to the hollow cavity (10) respectively, wherein One end is used for water vapor to flow in, and the other end is used for water vapor to flow out after liquefaction; the housing (3) is also provided with an air inlet end and an air outlet end, and the air inlet end is used to connect the air supply device (30) The air outlet is connected to the air inlet of external equipment, and the air supply device (30) is used to pass air into the interior of the housing (3) so that the air can communicate with the condensation pipe. (2) After heat exchange, it flows from the air outlet end into the air inlet of the external device. 2. The flue gas waste heat utilization device according to claim 1, characterized in that the hollow cavity (10) divides the side wall of the evaporator (1) into an inner wall (11) and an outer wall (12); Both ends of the condensation pipe (2) are connected to the hollow cavity (10) through the steam channel (41) and the condensation channel (42) respectively; and the steam channel (41) and the condensation channel (42) are both It communicates with the hollow cavity (10) through the outer wall (12). 3. The flue gas waste heat utilization device according to claim 2, characterized in that a flow guide assembly (5) is provided in the inner wall (11), and the flow guide assembly (5) is used to guide the flue gas to Flows close to the inner wall (11); the flow guide assembly (5) includes a guide column (51) and a mounting rod (52); one end of the installation rod (52) is arranged on the guide column (51) The upper end of the side wall, and the other end is provided on the inner wall (11); the guide column (51) is coaxial with the evaporator (1), and the bottom of the guide column (51) is in contact with the evaporator. (1) The bottom is flush, and the top of the guide column (51) is lower than the top of the evaporator (1). 4. The flue gas waste heat utilization device according to claim 2, characterized in that a distribution pipe (13) is provided inside the hollow cavity (10); the distribution pipe (13) is a coil spring structure, And a plurality of leakage holes (130) are spaced on the lower side of the distribution pipe (13); the distribution pipe (13) is located at the upper end of the hollow cavity (10); the condensation channel (42) runs through The outer wall (12) extends back into the hollow cavity (10) and is connected to the higher end port of the distribution pipe (13). 5. The flue gas waste heat utilization device according to claim 2, characterized in that the flow guide assembly (5) further includes a first guide plate (53), and the first guide plate (53) is a funnel. There are multiple first guide plates (53), and they are spaced from bottom to top on the side wall of the guide column (51). 6. The flue gas waste heat utilization device according to claim 2, characterized in that the flow guide assembly (5) further includes a second guide plate (54), and the second guide plate (54) is a spiral Like structure, the inner side of the second flow guide plate (54) is spirally arranged on the side wall of the flow guide column (51), and the outer side is in contact with the inner wall (11). 7. The flue gas waste heat utilization device according to claim 2, characterized in that the inner wall (11) and the guide column (51) form a smoke exhaust annular cavity (100), and the inner wall (11) is provided with There are multiple partition plates (110), and they are circumferentially spaced and distributed on the smoke exhaust annular cavity (100). 8. The flue gas waste heat utilization device according to claim 1, characterized in that the level of the inlet end of the condensation pipe (2) is higher than that of the hollow cavity (10) and is connected to the steam channel (41). The horizontal height of the end; The horizontal height of the outlet end of the condensation pipe (2) is higher than the horizontal height of the connection end of the distribution pipe (13) and the condensation channel (42). 9. Rotary kiln, used for heat treatment of garbage, has a kiln head and a kiln tail. The kiln head is provided with an air preheating channel (61), and a first sealing mechanism is provided at the connection; the kiln tail is provided with a smoke chamber ( 62), and a second sealing mechanism is provided at the connection; a flue (620) is provided on the smoke chamber (62); it is characterized in that it also includes a flue gas waste heat utilization method as described in any one of claims 1-8 Device, the evaporator (1) is connected to the flue (620), and the air preheating channel (61) is connected to the air outlet end. 10. The rotary kiln according to claim 9, characterized in that the flue (620) is a tubular structure, and the evaporator (1) is welded to the flue (620).