Control device for temperature difference between upper and lower parts of preheating zone of kiln

Abstract

The utility model discloses a device for controlling the temperature difference between the upper part and the lower part of a preheating zone of a kiln, which comprises the preheating zone of the tunnel kiln and a temperature sensor fixedly arranged on the inner side wall of the preheating zone of the tunnel kiln, a plurality of circulating drainage assemblies used for draining hot air flow above a preheating zone of the tunnel kiln are fixedly installed at the bottom of the inner wall of the temperature control cover, heat exchange pipes fixedly communicate with the two sides of each circulating drainage assembly, one end of each heat exchange pipe fixedly communicates with a circulating air guide pipe, and a low-temperature air inlet channel fixedly communicates with the middle of the top end of the temperature control cover. According to the control device for the temperature difference between the upper layer and the lower layer of the kiln preheating zone, the temperature control cover is additionally arranged on the top of the kiln, hot airflow on the upper layer of the preheating zone is led into the lower layer through the circulating drainage assembly and the pipeline, and the airflow in the kiln preheating zone is stirred through continuous circulation of the hot airflow; and the temperature difference balance effect is remarkable.

Description

Technical Field

[0001] The utility model relates to the technical field of tunnel kiln preheating, in particular to a control device for the upper and lower temperature differences in a kiln preheating zone. Background Art

[0002] Preheating is a necessary step in the billet firing process. Through preheating, the billet temperature is slowly raised to the temperature required for firing, so as to avoid cracks in the billet when the temperature is raised too quickly, and prevent the billet from becoming waste before entering the firing stage. The preheating zone of the tunnel kiln has two functions: dehydration and heating of the billet. During preheating, the residual water in the billet is evaporated to create conditions for subsequent calcination. At present, the preheating zone of the kiln has the following shortcomings in actual application:

[0003] As the high-temperature preheated air flow circulates in the preheating zone of the kiln, temperature stratification will occur. The temperature in the upper and middle layers is high, while the temperature in the lower layer is relatively low. At this time, the blanks on the upper kiln frame are heated rapidly and are prone to cracking. The blanks in the lower layer cannot be fully preheated, and the moisture cannot be fully evaporated. After firing, there will be defects such as blank bubbles and burrs. Utility Model Content

[0004] The utility model aims to provide a control device for the upper and lower temperature difference of a kiln preheating zone to solve the problem in the prior art that the upper and lower temperature difference of the existing kiln preheating zone is large and cannot be controlled during preheating.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a control device for the upper and lower temperature differences of a kiln preheating zone, comprising a tunnel kiln preheating zone and a temperature sensor fixedly installed on the inner wall of the tunnel kiln preheating zone, a temperature control cover is fixedly arranged on the top of the tunnel kiln preheating zone, a plurality of circulation drainage components for guiding the hot air flow above the tunnel kiln preheating zone are fixedly installed on the bottom of the inner wall of the temperature control cover, both sides of the circulation drainage components are fixedly connected with heat exchange pipes, one end of the heat exchange pipe is fixedly connected with a circulation air guide pipe, the middle part of the top of the temperature control cover is fixedly connected with a low-temperature air inlet channel, an air intake fan is fixedly installed inside the low-temperature air inlet channel, and both ends of the temperature control cover are fixedly connected with exhaust channels.

[0006] Preferably, the bottom end of the circulating air duct extends to the bottom of the preheating zone of the tunnel kiln, and a stirring air nozzle is fixedly installed on the circulating air duct.

[0007] Preferably, the circulation drainage assembly includes a manifold and a conducting pipe fixedly connected to the top of the manifold, a high-temperature circulation fan is fixedly installed in the middle of the conducting pipe, a three-way pipe is fixedly connected to the top of the conducting pipe, both ends of the three-way pipe are respectively fixedly arranged on two oppositely arranged heat exchange tubes, and a plurality of drainage hoods are fixedly connected to the bottom end of the manifold, and the drainage hoods are arranged on the top of the inner wall of the preheating zone of the tunnel kiln.

[0008] Preferably, a controller is fixedly installed on one side of the top of the temperature control cover, and the plurality of high-temperature circulation fans and air intake fans are electrically connected to the controller, and the controller is electrically connected to the temperature sensor.

[0009] Preferably, a dust filter is fixedly provided at the top of the low-temperature air inlet passage to prevent dust from entering the temperature control cover.

[0010] Preferably, the heat exchange tube is arranged in a spiral shape, which can increase the circulation time of the hot air flow inside the preheating zone in the heat exchange tube, so as to facilitate heat exchange with the outside air and prevent the temperature inside the preheating zone from being too high.

[0011] Preferably, a kiln car is provided at the bottom of the preheating zone of the tunnel kiln, and a billet rack for firing billets is fixedly mounted on the kiln car, so as to facilitate the placement of billets.

[0012] Compared with the prior art, the beneficial effects of the utility model are:

[0013] The upper and lower temperature difference control device of the kiln preheating zone is provided with a temperature control cover on the top of the kiln, and the hot air flow in the upper layer of the preheating zone is introduced into the lower layer by using the circulation guide assembly and the pipeline. The hot air flow is continuously circulated to stir the air flow in the preheating zone of the kiln, stabilize the upper and lower temperature difference in the preheating zone, and achieve a significant temperature difference balancing effect.

[0014] A low-temperature air flow channel is added in the temperature control hood. When the temperature in the preheating zone is higher than the set value, external cold air can be automatically introduced into the temperature control hood, and heat is exchanged with the heat circulating in the preheating zone through the heat exchange tube, thereby controlling the temperature in the preheating zone and preventing the preheating temperature in the preheating zone from being too high, which is beneficial to reducing the cracking of the billet. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a front cross-sectional view of the temperature difference control device of the utility model;

[0016] Figure 2 This is a schematic diagram of the structure of the temperature control cover of the utility model;

[0017] Figure 3 This is a schematic diagram of the structure of the circulation drainage component of the utility model;

[0018] Figure 4It is an enlarged view of part A of the utility model.

[0019] In the figure: 1. Tunnel kiln preheating zone; 2. Kiln car; 3. Temperature control hood; 4. Drainage hood; 5. Manifold; 6. Controller; 7. Low-temperature air intake channel; 8. Air intake fan; 9. Heat exchange pipe; 10. Exhaust channel; 11. Temperature sensor; 12. Circulating air duct; 13. Stirring air nozzle; 14. Conducting duct; 15. High-temperature circulating fan; 16. Three-way pipe; 17. Dust filter; 18. Billet rack. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0021] See also Figure 1-4 The utility model provides a control device for the upper and lower temperature differences of a kiln preheating zone, comprising a tunnel kiln preheating zone 1 and a temperature sensor 11 fixedly installed on the inner wall of the tunnel kiln preheating zone 1, a temperature control cover 3 is fixedly installed on the top of the tunnel kiln preheating zone 1, a plurality of circulation drainage components for guiding the hot air flow above the tunnel kiln preheating zone 1 are fixedly installed on the bottom of the inner wall of the temperature control cover 3, both sides of the circulation drainage components are fixedly connected with heat exchange pipes 9, one end of the heat exchange pipe 9 is fixedly connected with a circulation air guide pipe 12, the middle part of the top of the temperature control cover 3 is fixedly connected with a low-temperature air inlet channel 7, an air intake fan 8 is fixedly installed inside the low-temperature air inlet channel 7, both ends of the temperature control cover 3 are fixedly connected with exhaust channels 10, the bottom end of the circulation air guide pipe 12 extends to the bottom of the tunnel kiln preheating zone 1, a stirring air nozzle 13 is fixedly installed on the circulation air guide pipe 12, a dust filter 17 is fixedly installed on the top of the low-temperature air inlet channel 7, and the heat exchange pipe 9 is arranged in a spiral shape;

[0022] During use, when the temperature sensor 11 detects that the temperature inside the tunnel kiln preheating zone 1 is higher than the set value, the air intake fan 8 will work, and continuously introduce external cold air through the low-temperature air intake channel 7. The external airflow enters the temperature control cover 3 and contacts the heat exchange tube 9, cooling the hot air flow in the preheating zone flowing inside. The gas after heat exchange is discharged through the exhaust channel 10 until the temperature inside the tunnel kiln preheating zone 1 returns to the set value, and the temperature control is precise.

[0023] See also Figure 1 , Figure 2 , Figure 3 and Figure 4, further, the circulation drainage component includes a manifold 5 and a conducting pipe 14 fixedly connected to the top of the manifold 5, a high-temperature circulation fan 15 is fixedly installed in the middle of the conducting pipe 14, a three-way pipe 16 is fixedly connected to the top of the conducting pipe 14, and the two ends of the three-way pipe 16 are respectively fixedly arranged on two heat exchange pipes 9 arranged opposite to each other, and the bottom end of the manifold 5 is fixedly connected to a plurality of drainage hoods 4, and the drainage hoods 4 are arranged on the top of the inner wall of the tunnel kiln preheating zone 1, and a controller 6 is fixedly installed on one side of the top of the temperature control hood 3, and the plurality of high-temperature circulation fans 15 and the air intake fan 8 are electrically connected to the controller 6, and the controller 6 is electrically connected to the temperature sensor 11;

[0024] When in use, during the preheating process, under the action of the high-temperature circulating fan 15, the hot air flow at the top of the preheating zone will continue to enter the manifold 5 through the drainage hood 4, and then enter the three-way pipe 16 through the conducting pipe 14, and then enter the heat exchange tube 9 at both ends of the three-way pipe 16, and finally enter the agitation air nozzle 13 through the circulating air guide pipe 12, and the air flow is ejected from the bottom of the preheating zone, and the temperature difference between the upper and lower layers in the preheating zone is balanced through the circulating air flow.

[0025] See also Figure 1 , further, a kiln car 2 is provided at the bottom of the tunnel kiln preheating zone 1, and a billet rack 18 for billet firing is fixedly installed on the kiln car 2;

[0026] When in use, the kiln car 2 can move on the bottom of the tunnel kiln preheating zone 1, and the blanks are placed on the blank rack 18. The kiln car 2 drives the blanks to move in the tunnel kiln preheating zone 1 to achieve preheating of the blanks.

[0027] When the embodiment of the present application is in use: the length of the tunnel kiln preheating zone 1 is usually between 25 and 30 meters, a temperature control hood 3 is installed every four to five meters above the preheating zone, and the preheating temperature of each area of ​​the controller 6 is set. During the preheating operation, the high-temperature circulation fan 15 will continuously suck the airflow in the conducting pipe 14. Under the action of negative pressure, the hot air flow at the top of the preheating zone will continue to enter the manifold 5 through the drainage hood 4, and then enter the three-way pipe 16 through the conducting pipe 14, and then enter the heat exchange pipe 9, and finally enter the agitation air nozzle 13 through the circulating air guide pipe 12, and the airflow is ejected from the bottom of the preheating zone. By making the airflow continue to circulate from bottom to top in the preheating zone and between the pipes, the temperature in the tunnel kiln preheating zone 1 is stirred to balance the upper and lower temperature differences.

[0028] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art may still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A control device for the temperature difference between the upper and lower temperature zones of a kiln preheating zone, comprising a tunnel kiln preheating zone (1) and a temperature sensor (11) fixedly mounted on the inner wall of the tunnel kiln preheating zone (1), characterized in that: A temperature control cover (3) is fixedly arranged at the top of the tunnel kiln preheating zone (1), and a plurality of circulation and drainage components for guiding the hot air flow above the tunnel kiln preheating zone (1) are fixedly installed at the bottom of the inner wall of the temperature control cover (3). Both sides of the circulation and drainage components are fixedly connected with heat exchange pipes (9), and one end of the heat exchange pipe (9) is fixedly connected with a circulation air guide pipe (12). The middle part of the top of the temperature control cover (3) is fixedly connected with a low-temperature air intake channel (7), and an air intake fan (8) is fixedly installed inside the low-temperature air intake channel (7). Both ends of the temperature control cover (3) are fixedly connected with exhaust channels (10).

2. The control device for the upper and lower temperature difference of the kiln preheating zone according to claim 1 is characterized in that: The bottom end of the circulating air duct (12) extends to the bottom of the tunnel kiln preheating zone (1), and a stirring air nozzle (13) is fixedly mounted on the circulating air duct (12).

3. The control device for the upper and lower temperature difference of the kiln preheating zone according to claim 1 is characterized in that: The circulation drainage component comprises a manifold (5) and a conducting pipe (14) fixedly connected to the top of the manifold (5); a high-temperature circulation fan (15) is fixedly installed in the middle of the conducting pipe (14); a three-way pipe (16) is fixedly connected to the top of the conducting pipe (14); two ends of the three-way pipe (16) are respectively fixedly arranged on two heat exchange pipes (9) arranged opposite to each other; the bottom end of the manifold (5) is fixedly connected to a plurality of drainage hoods (4); and the drainage hoods (4) are arranged on the top of the inner wall of the tunnel kiln preheating zone (1).

4. The control device for the upper and lower temperature difference of the kiln preheating zone according to claim 3 is characterized in that: A controller (6) is fixedly mounted on one side of the top of the temperature control cover (3); the plurality of high-temperature circulation fans (15) and the air intake fans (8) are electrically connected to the controller (6); and the controller (6) is electrically connected to the temperature sensor (11).

5. The control device for the upper and lower temperature difference of the kiln preheating zone according to claim 1 is characterized in that: A dust filter (17) is fixedly arranged at the top end of the low-temperature air inlet passage (7).

6. The control device for the upper and lower temperature difference of the kiln preheating zone according to claim 1 is characterized in that: The heat exchange tube (9) is arranged in a spiral shape.

7. The control device for the upper and lower temperature difference of the preheating zone of the kiln according to claim 1 is characterized in that: A kiln car (2) is provided at the bottom of the tunnel kiln preheating zone (1), and a blank rack (18) for blank firing is fixedly mounted on the kiln car (2).

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