A rotary kiln waste heat recovery device

Abstract

The utility model belongs to rotary kiln technical field especially relates to a rotary kiln waste heat recovery device, contains the rotary kiln of kiln head, kiln tail, first casing, separating mechanism, conveying mechanism, spray mechanism, heat exchange device and filter device, kiln tail is equipped with flue gas leading-out pipe, first casing is installed in rotary kiln side, is opened with flue gas leading-out pipe intercommunication's flue gas import; The separating mechanism and its below conveying mechanism are equipped in first casing, respectively separate, convey the dust in flue gas; Spray mechanism is installed in first casing side, with dust heat exchange produces steam; Heat exchange device connects separating mechanism and spray mechanism to recover flue gas and steam waste heat, and filter device is connected between; Realize flue gas solid gas separation through separating mechanism, conveying mechanism sends waste residue to spray mechanism, utilizes waste residue heat energy to generate steam, and flue gas and steam are introduced into heat exchange device after filtration, realize the waste heat recovery of flue gas and most waste residue, improve effect, avoid waste.

Description

Technical Field

[0001] This utility model belongs to the field of rotary kiln technology, and in particular relates to a rotary kiln waste heat recovery device. Background Technology

[0002] A rotary kiln is a large-scale rotary calcining equipment widely used in industries such as metallurgy, building materials, chemicals, and environmental protection. Its core function is to enable materials to complete processes such as drying, preheating, calcining, and cooling at high temperatures through the rotation of the cylinder.

[0003] Traditional rotary kilns typically discharge large amounts of flue gas during operation. This flue gas is usually at a high temperature (the temperature of the flue gas at the kiln tail is usually 300~800℃). Recovering the heat energy from this part not only reduces the difficulty of subsequent flue gas treatment but also achieves good energy-saving effects. However, before recovering the waste heat from the flue gas, it is usually necessary to filter the flue gas to remove pollutants that may harm the waste heat recovery device. Existing rotary kilns usually only recover waste heat from the filtered flue gas, and the filtered waste residue is usually left to cool naturally. This undoubtedly causes a great waste of the heat energy contained in the waste residue, resulting in poor overall heat energy recovery efficiency of the flue gas. Utility Model Content

[0004] The purpose of this invention is to address the aforementioned technical problems by providing a rotary kiln waste heat recovery device that can simultaneously recover heat energy from flue gas and waste residue.

[0005] In view of this, the present invention provides a rotary kiln waste heat recovery device, comprising:

[0006] A rotary kiln includes a kiln head and a kiln tail, with a flue gas outlet pipe installed at the kiln tail.

[0007] The first housing is installed on the side of the rotary kiln and has a flue gas inlet connected to a flue gas outlet pipe.

[0008] A separation mechanism, installed inside the first housing, is used to separate dust from the flue gas;

[0009] A conveying mechanism is installed inside the first housing and located below the separation mechanism, and is used to convey dust.

[0010] A spray mechanism is installed on the side of the first housing and is used for heat exchange with dust and to generate steam;

[0011] A heat exchange device is connected to the separation mechanism and the spraying mechanism, and is used to recover waste heat from flue gas and steam.

[0012] A filtration device is connected between the heat exchange device and the separation mechanism, as well as between the heat exchange device and the spraying mechanism.

[0013] In the above technical solution, further:

[0014] The first housing includes an inlet channel and an outlet channel, both of which are vertically arranged, and a separation cavity is formed at the lowest end of the inlet channel and the outlet channel;

[0015] The separation mechanism includes a filter screen disposed between the outlet channel and the separation chamber.

[0016] In the above technical solution, further:

[0017] Multiple anti-backflow plates are evenly spaced at the lowest point of the separation chamber, and a channel for dust to fall out is formed between two adjacent anti-backflow plates.

[0018] In the above technical solution, further:

[0019] The anti-backflow plate is in an inverted V shape.

[0020] In the above technical solution, the conveying mechanism further includes:

[0021] The motor is mounted on the side of the first housing;

[0022] The rotating shaft is installed below the separation chamber, with one end connected to the output end of the motor and the other end extending to the spraying mechanism;

[0023] The spiral blades are mounted on the rotating shaft and extend to the spray mechanism, and are used to propel the dust to the spray mechanism.

[0024] In the above technical solution, the spraying mechanism further includes:

[0025] The second housing is installed on the side of the first housing;

[0026] The spray pipe has a water supply unit connected to one end and extends into the second housing at the other end. It is equipped with multiple spray heads at equal intervals and is used to spray the dust that is conveyed by the conveying mechanism to the spraying mechanism.

[0027] In this process, the spray water from the spray pipe exchanges heat with the dust and generates steam.

[0028] In the above technical solution, further:

[0029] The first housing has a first discharge pipe that communicates with the outlet channel, and the second housing has a second discharge pipe that communicates with the first discharge pipe and the interior of the second housing respectively, so that the steam generated in the second housing mixes with the flue gas discharged from the first housing and is then transported to the filter device after mixing.

[0030] In the above technical solution, further:

[0031] A guide tube is provided between the first housing and the second housing, and the guide tube is adapted to the helical blade.

[0032] The beneficial effects of this utility model are as follows:

[0033] 1. The flue gas is separated into solid and gas components by a separation mechanism, and the separated solid waste is transported to a spraying mechanism for spraying. The heat energy in the waste is used to heat the waste to form steam. The separated flue gas and steam are then filtered again by a filtration device and then introduced into a heat exchange device. This allows for the recovery of waste heat from the flue gas and most of the waste, greatly improving the efficiency of waste heat recovery and avoiding the waste of heat energy.

[0034] 2. By adopting vertically set inlet and outlet channels, large dust particles can be easily retained in the separation chamber by gravity. The filter screen can further ensure the interception effect of dust in the flue gas and prevent dust from being lifted by the airflow and entering the outlet channel again, thus facilitating the recovery of heat energy from the retained large dust particles.

[0035] 3. The anti-backflow plate can effectively reduce the dust falling into the conveying mechanism from being carried up by the airflow again, avoid increasing the dust level in the separation chamber, ensure the filtration effect of the filter screen, and the inverted V-shape can facilitate the dust falling on the anti-backflow plate to slide into the conveying mechanism.

[0036] 4. By mixing the steam generated from the heat transfer between the spray water and the waste residue with the flue gas that has undergone initial filtration and is discharged from the first discharge pipe, the fine dust remaining in the flue gas is agglomerated, making it easier for subsequent filtration devices to remove it. On the other hand, the flue gas is also cooled to a certain extent to meet the heat resistance requirements of some filtration devices, thereby achieving temperature control and improving applicability. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure of this utility model;

[0038] Figure 2 This is a partial structural diagram of the first housing of this utility model;

[0039] Figure 3 This is a partial top view of the first housing of this utility model;

[0040] Figure 4 This is a utility model Figure 3 Enlarged view of section AA;

[0041] The markings in the diagram represent: 1. Rotary kiln; 100. Kiln head; 101. Kiln tail; 102. Flue gas outlet pipe; 2. First shell; 20. Inlet channel; 21. Outlet channel; 22. Anti-backflow plate; 3. Flue gas inlet; 4. Separation mechanism; 40. Separation chamber; 41. Filter screen; 5. Conveying mechanism; 50. Motor; 51. Rotating shaft; 52. Spiral blade; 6. Spraying mechanism; 60. Second shell; 61. Spray pipe; 62. Spray head; 7. Heat exchange device; 8. Filtering device; 9. First discharge pipe; 10. Second discharge pipe; 11. Guide pipe. Detailed Implementation

[0042] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0043] Example 1:

[0044] This embodiment provides a rotary kiln waste heat recovery device, including:

[0045] The rotary kiln 1 includes a kiln head 100 and a kiln tail 101, and a flue gas outlet pipe 102 is provided at the kiln tail 101.

[0046] The first housing 2 is installed on the side of the rotary kiln 1 and has a flue gas inlet 3 connected to the flue gas outlet pipe 102.

[0047] The separation mechanism 4 is installed inside the first housing 2 and is used to separate dust from the flue gas;

[0048] The conveying mechanism 5 is installed inside the first housing 2 and located below the separation mechanism 4, and is used to convey dust.

[0049] The spray mechanism 6 is installed on the side of the first housing 2 and is used to exchange heat with the dust and generate steam;

[0050] The heat exchange device 7 is connected to the separation mechanism 4 and the spraying mechanism 6, and is used to recover waste heat from flue gas and steam.

[0051] The filter device 8 is connected between the heat exchange device 7 and the separation mechanism 4, and between the heat exchange device 7 and the spraying mechanism 6.

[0052] Among them, the rotary kiln 1, the heat exchange device 7 and the filter device 8 are all existing technologies. For example, the heat exchange device 7 can be a plate heat exchanger, a waste heat boiler, etc., and the filter device 8 can be a bag dust collector, etc. The specific structure of each can be obtained from traditional equipment, and will not be described in detail in this application.

[0053] As can be seen in this embodiment, the flue gas is separated into solid and gas by the separation mechanism 4, and the separated solid waste residue is transported to the spraying mechanism 6 by the conveying mechanism 5 for spraying. The heat energy in the waste residue is used to heat and form steam. Then, the separated flue gas and steam are filtered again by the filter device 8 and then introduced into the heat exchange device 7. This allows for the recovery of waste heat from the flue gas and most of the waste residue, thereby greatly improving the waste heat recovery effect and avoiding the waste of heat energy.

[0054] Example 2:

[0055] This embodiment provides a rotary kiln waste heat recovery device, which, in addition to the technical solutions of the above embodiments, also has the following technical features:

[0056] The first housing 2 includes an inlet channel 20 and an outlet channel 21, both of which are vertically arranged, and a separation cavity 40 is formed at the lowest end of the inlet channel 20 and the outlet channel 21.

[0057] The separation mechanism 4 includes a filter screen 41 disposed between the outlet channel 21 and the separation chamber 40. The filter screen 41 is required to be able to filter most of the dust in the corresponding flue gas. The material and mesh number of the filter screen 41 can be selected according to different materials. This is a traditional and conventional operation, and will not be described in detail in this application.

[0058] As can be seen from this embodiment, by adopting the vertically arranged inlet channel 20 and outlet channel 21, it is convenient to leave large dust particles in the separation chamber 40 by gravity. Combined with the setting of the filter screen 41, it can further ensure the interception effect of dust in the flue gas and prevent the dust from being lifted by the airflow and entering the outlet channel 21 again, thereby facilitating the recovery of heat energy from the retained large dust particles.

[0059] Furthermore, a curved section can be provided within the inlet channel 20 to increase the collision between dust in the flue gas and the inner wall of the first housing 2, thereby increasing the separation effect.

[0060] Example 3:

[0061] This embodiment provides a rotary kiln waste heat recovery device, which, in addition to the technical solutions of the above embodiments, also has the following technical features:

[0062] The lowest part of the separation chamber 40 is provided with multiple anti-backflow plates 22 at equal intervals, and a channel for dust to fall out is formed between two adjacent anti-backflow plates 22.

[0063] As can be seen from this embodiment, the anti-backflow plate 22 can effectively reduce the dust falling into the conveying mechanism 5 from being carried up by the airflow again, avoid increasing the dust level in the separation chamber 40, ensure the filtration effect of the filter screen 41, and reduce the risk of the filter screen 41 becoming clogged.

[0064] Example 4:

[0065] This embodiment provides a rotary kiln waste heat recovery device, which, in addition to the technical solutions of the above embodiments, also has the following technical features:

[0066] The anti-backflow plate 22 is in an inverted V shape.

[0067] As can be seen from this embodiment, by making the anti-backflow plate 22 into an inverted V shape, the dust falling on the anti-backflow plate 22 can slide into the conveying mechanism 5, reducing the deposition of dust on the anti-backflow plate 22.

[0068] Example 5:

[0069] This embodiment provides a rotary kiln waste heat recovery device, which, in addition to the technical solutions of the above embodiments, also has the following technical features: the conveying mechanism 5 includes:

[0070] Motor 50 is mounted on the side of the first housing 2;

[0071] The rotating shaft 51 is installed below the separation chamber 40, with one end connected to the output end of the motor 50 and the other end extending to the spraying mechanism 6;

[0072] The spiral blade 52 is sleeved on the rotating shaft 51 and extends to the spray mechanism 6, and is used to push the dust to the spray mechanism 6.

[0073] As can be seen from this embodiment, by using a motor 50 to drive the rotating shaft 51, and then using the spiral blades 52 to push the dust to the spraying mechanism 6, the convenience of dust transportation is ensured.

[0074] Example 6:

[0075] This embodiment provides a rotary kiln waste heat recovery device, which, in addition to the technical solutions of the above embodiments, also has the following technical features: the spray mechanism 6 includes:

[0076] The second housing 60 is installed on the side of the first housing 2;

[0077] The spray pipe 61 is connected to a water supply unit at one end and extends into the second housing 60 at the other end. It is provided with multiple spray heads 62 at equal intervals and is used to spray the dust conveyed by the conveying mechanism 5 to the spraying mechanism 6.

[0078] The spray water from the spray pipe 61 exchanges heat with the dust and generates steam.

[0079] Meanwhile, the specific structure of the water supply unit is based on existing technology, which can provide spray water to the sprinkler pipes. It may include a water tank and a water pump, etc., which will not be described in detail here.

[0080] As can be seen from this embodiment, by spraying an appropriate amount of spray water onto the surface of the high-temperature waste residue, the spray water can be heated by the heat energy of the waste residue to form high-temperature steam, thereby recovering the residual heat in the waste residue and avoiding the waste of heat energy caused by letting the waste residue cool naturally.

[0081] At the same time, spraying an appropriate amount of water can moisten the dry dust, thereby avoiding the risk of dust rising during subsequent cleaning and improving safety.

[0082] Furthermore, the second shell 60 can be cleaned periodically according to actual conditions, thereby ensuring the heat energy recovery effect of this part of the waste residue;

[0083] Preferably, the multiple spray heads 62 on the spray pipe 61 can be arranged on the side of the spray pipe 61, which can reduce the risk of the spray heads 62 being blocked, facilitate the control of the spray water input, and extend the service life.

[0084] Example 7:

[0085] This embodiment provides a rotary kiln waste heat recovery device, which, in addition to the technical solutions of the above embodiments, also has the following technical features:

[0086] The first housing 2 has a first discharge pipe 9 that communicates with the discharge channel 21, and the second housing 60 has a second discharge pipe 10 that communicates with the first discharge pipe 9 and the interior of the second housing 60 respectively, so that the steam generated in the second housing 60 is mixed with the flue gas discharged from the first housing 2, and then transported to the filter device 8 after mixing.

[0087] As can be seen from this embodiment, by mixing the steam generated by heat transfer between the spray water and the waste residue with the flue gas that has undergone initial filtration and discharged from the first discharge pipe 9, on the one hand, the fine dust remaining in the flue gas is agglomerated, which makes it easier for the subsequent filtration device 8 to remove it; on the other hand, it can also cool the flue gas to a certain extent to meet the heat resistance requirements of some filtration devices 8, thereby achieving the effect of temperature control and improving applicability.

[0088] Specifically, for example, the temperature resistance requirement of the filter media of some bag filter equipment is 200-250℃, and after separating flue gas (300-800℃) and mixing steam, it can usually still be maintained at 150-200℃, which is higher than the minimum inlet temperature of most heat exchange devices, such as some plate heat exchangers and waste heat boilers with a minimum inlet temperature of 100℃.

[0089] The generated steam can also be branched out, specifically, to generate hot water (for heating the plant area) or low-pressure steam (for preheating the feed of rotary kiln 1) through heat exchange, thereby realizing the cascade recovery of "high temperature flue gas → medium temperature flue gas → waste heat utilization", which greatly improves the heat utilization rate and ensures the effect of waste heat recovery.

[0090] Example 8:

[0091] This embodiment provides a rotary kiln waste heat recovery device, which, in addition to the technical solutions of the above embodiments, also has the following technical features:

[0092] A guide tube 11 is provided between the first housing 2 and the second housing 60, and the guide tube 11 is adapted to the spiral blade 52.

[0093] As can be seen from this embodiment, by setting the guide tube 11 to be adapted to the spiral blade 52, a small gap is maintained between the spiral blade 52 and the inner wall of the guide tube 11, thereby effectively reducing the exchange of flue gas or steam between the first housing 2 and the second housing 60, which has a certain promoting effect on the isolation between the first housing 2 and the second housing 60, avoiding excessive exchange of flue gas or steam between the first housing 2 and the second housing 60, and preventing the impact on the waste heat recovery effect.

[0094] The embodiments of this application have been described above with reference to the accompanying drawings. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. This application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A rotary kiln waste heat recovery device, characterized in that, include: The rotary kiln (1) includes a kiln head (100) and a kiln tail (101), and a flue gas outlet pipe (102) is provided at the kiln tail (101). The first shell (2) is installed on the side of the rotary kiln (1) and has a flue gas inlet (3) connected to the flue gas outlet pipe (102); The separation mechanism (4) is installed inside the first housing (2) and is used to separate dust from the flue gas; The conveying mechanism (5) is installed inside the first housing (2) and located below the separation mechanism (4), and is used to convey dust. The spray mechanism (6) is installed on the side of the first housing (2) and is used to exchange heat with the dust and generate steam; A heat exchange device (7) is connected to the separation mechanism (4) and the spraying mechanism (6) and is used to recover waste heat from flue gas and steam. The filter device (8) is connected between the heat exchange device (7) and the separation mechanism (4) and between the heat exchange device (7) and the spraying mechanism (6).

2. The rotary kiln waste heat recovery device according to claim 1, characterized in that: The first housing (2) includes an inlet channel (20) and an outlet channel (21), and both the inlet channel (20) and the outlet channel (21) are vertically arranged, and a separation cavity (40) is formed at the lowest end of the inlet channel (20) and the outlet channel (21). The separation mechanism (4) includes a filter screen (41) disposed between the outlet channel (21) and the separation chamber (40).

3. The rotary kiln waste heat recovery device according to claim 2, characterized in that: The separation chamber (40) is provided with multiple anti-backflow plates (22) at equal intervals at its lowest position, and a dust discharge channel is formed between each pair of adjacent anti-backflow plates (22).

4. The rotary kiln waste heat recovery device according to claim 3, characterized in that: The anti-backflow plate (22) is in the shape of an inverted V.

5. The rotary kiln waste heat recovery device according to claim 2, characterized in that, The conveying mechanism (5) includes: The motor (50) is mounted on the side of the first housing (2); A rotating shaft (51) is installed below the separation chamber (40), with one end connected to the output end of the motor (50) and the other end extending to the spraying mechanism (6). The spiral blade (52) is fitted on the rotating shaft (51) and extends to the spray mechanism (6), and is used to push the dust to the spray mechanism (6).

6. The rotary kiln waste heat recovery device according to claim 5, characterized in that, The spraying mechanism (6) includes: The second housing (60) is installed on the side of the first housing (2); The spray pipe (61) is connected to a water supply unit at one end and extends into the second housing (60) at the other end. Multiple spray heads (62) are provided at equal intervals and are used to spray the dust that is conveyed from the conveying mechanism (5) to the spraying mechanism (6). The spray water sprayed from the spray pipe (61) exchanges heat with the dust and generates steam.

7. The rotary kiln waste heat recovery device according to claim 6, characterized in that: The first housing (2) is provided with a first discharge pipe (9) that communicates with the outlet channel (21), and the second housing (60) is provided with a second discharge pipe (10) that communicates with the first discharge pipe (9) and the interior of the second housing (60), so that the steam generated in the second housing (60) is mixed with the flue gas discharged from the first housing (2) and then transported to the filter device (8) after mixing.

8. The rotary kiln waste heat recovery device according to claim 6, characterized in that: A guide tube (11) is provided between the first housing (2) and the second housing (60), and the guide tube (11) is adapted to the spiral blade (52).

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