A pusher kiln for firing alumina powder

Abstract

This invention belongs to the technical field of material calcination equipment. It discloses a pusher kiln for calcining alumina powder, comprising a kiln body, a conveying assembly, a heating assembly, and a temperature control assembly. The kiln cavity is divided into a preheating section, a calcination section, and a cooling section. The conveying assembly transports powder via tracks, pushers, and a pushing component. The heating assembly provides uniform heating using mixed flue gas pipes, gas pipes, and burners. The gas pipe layout eliminates injection blind spots. The temperature control assembly precisely controls the temperature using a temperature detector, a control unit, and an execution unit. This pusher kiln offers precise temperature control, uniform heating, high energy efficiency, a reasonable structure, and good stability, thus improving the quality and efficiency of calcining nano-alumina powder.

Description

Technical Field

[0001] This invention relates to the field of material firing equipment technology, and more specifically, to a pusher kiln for firing alumina powder. Background Technology

[0002] In the production of nano-alumina powder, the calcination process is crucial, directly affecting the quality and performance of the nano-alumina powder. However, current traditional calcination equipment has many problems.

[0003] Most traditional pusher kilns lack precision in temperature control. The firing of nano-alumina powder is extremely demanding in terms of temperature; even slight temperature fluctuations can alter the powder's crystal structure, particle size distribution, and other properties. For example, in some traditional pusher kilns, uneven heating leads to significant temperature differences at different locations within the kiln, resulting in inconsistent quality of the fired nano-alumina powder, which fails to meet the high-end applications' requirements for powder quality consistency.

[0004] Meanwhile, the heating components of traditional pusher kilns have some defects. The unreasonable layout of the gas pipes and burners results in injection blind spots within the kiln, preventing some areas from being fully heated and affecting the overall firing quality. Furthermore, the type and performance of the burners also affect the firing effect; some traditional burners have unstable heat output power, making it difficult to adjust them in a timely manner according to changes in kiln temperature. Summary of the Invention

[0005] To overcome the aforementioned deficiencies of the prior art and to achieve the above objectives, the present invention provides the following technical solution:

[0006] A pusher kiln for calcining alumina powder includes:

[0007] The kiln body has a kiln cavity arranged longitudinally within it, and the kiln cavity consists of a preheating section, a calcination section, and a cooling section in sequence from the inlet to the outlet.

[0008] The conveying assembly includes a track fixedly installed at the bottom of the kiln cavity, a pusher plate movably installed on the track, a sagger containing nano-powder placed on the pusher plate, and a pushing assembly provided at one end of the track. The pushing assembly drives the pusher plate to pass through the preheating section, calcination section and cooling section sequentially along the track.

[0009] The heating assembly includes a mixed gas pipeline disposed at the top of the kiln body, multiple rows of gas pipes disposed within the kiln cavity, the mixed gas pipeline being externally connected to a gas inlet pipe and a combustion-supporting blower, the gas pipes being vertically disposed within the kiln cavity and mounted at the top of the kiln body, the mixed gas pipeline being connected to the gas pipes via a connecting pipe and supplying combustible mixed gas into the gas pipes, and burners being vertically and evenly distributed in the lower part of the gas pipes, the burners facing the passing sagger;

[0010] The temperature control component includes a temperature detector, a control unit, and an execution unit. Multiple temperature detectors are installed inside the kiln cavity to feed back the temperature information of the preheating section, the calcination section, and the cooling section to the control unit. The control unit controls the execution unit to adjust the heat output power of the burner based on the temperature information fed back by the temperature detectors.

[0011] The gas pipes are evenly distributed within the calcination section of the kiln cavity. Multiple rows of gas pipes are arranged in a matrix or staggered pattern within the calcination section. The spacing between the flue gas connecting pipes in each row of gas pipes is no more than 30cm, so that the burner completely covers the transverse cross section inside the kiln body, with no injection blind spots.

[0012] Furthermore, multiple saggers are stacked on the push plate, and at least one side of each sagger is provided with a gas pipe, with the edge of the sagger being no more than 20 cm away from the nearest burner.

[0013] Furthermore, the burner is a ceramic burner.

[0014] Furthermore, the execution unit includes an electromagnetic flow valve disposed on the connecting pipe, a gas valve disposed on the gas pipe, and the combustion-supporting blower.

[0015] Furthermore, three rows of gas pipes are arranged on the push plate, and the stacked crucibles are located between the gas pipes.

[0016] Furthermore, the pushing component is a long-stroke hydraulic rod disposed outside the kiln body, which pushes the pusher plate to move on the track.

[0017] The technical effects and advantages of this invention are as follows:

[0018] 1. Precise temperature control: Through the precise control of the temperature control components, the temperature of each section in the kiln can be monitored and adjusted in real time, ensuring that the nano alumina powder is always in the optimal temperature environment during the firing process, which effectively improves the consistency and stability of product quality.

[0019] 2. Uniform heating: The reasonable layout of the gas pipes and burners in the heating assembly eliminates the injection blind zone, so that the transverse cross section inside the kiln can be heated evenly, avoiding product quality problems caused by uneven heating.

[0020] 3. Reasonable structural design: The good coordination between the conveying components, heating components and temperature control components ensures the smooth conveying, heating and temperature control of nano alumina powder in the kiln, and improves production efficiency. Attached Figure Description

[0021] Figure 1 This is a longitudinal cross-sectional view of the present invention;

[0022] Figure 2 This is a schematic cross-sectional view of the present invention;

[0023] Figure 3 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0024] In the attached diagram, 1 is the kiln body, 2 is the pusher plate, 3 is the sagger, 4 is the mixed gas pipeline, 5 is the connecting pipe, 6 is the gas inlet pipe, 7 is the electromagnetic flow valve, 8 is the burner, 9 is the gas pipe, 10 is the gas valve, 11 is the combustion fan, 101 is the preheating section, 102 is the calcination section, 103 is the cooling section, and 104 is the kiln cavity. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] like Figures 1-3 The diagram shows a pusher-plate kiln 2 for calcining nano-alumina powder. The kiln body 1 of this pusher-plate kiln 2 has a kiln cavity 104 arranged longitudinally inside. This kiln cavity 104 is divided into a preheating section 101, a calcination section 102, and a cooling section 103 from the inlet to the outlet. The length of the preheating section 101 can be determined based on the influence of high-temperature combustion inside the calcination section 102 on the temperature of the preheating section 101. This design can fully utilize the waste heat generated by the calcination section 102 to preheat the nano-alumina powder entering the kiln, achieving efficient energy utilization. The length of the cooling section 103 meets the requirement of minimizing the influence of the combustion section on the rear of the cooling section 103, ensuring that the nano-alumina powder can be stably cooled during the cooling process, avoiding performance issues caused by uneven cooling or excessively high temperatures.

[0027] The conveying assembly is a key component to ensure the smooth transport of nano-alumina powder within the kiln. It includes a track fixedly installed at the bottom of the kiln cavity 104. The pusher plate 2 can move flexibly on the track under the control of the pushing assembly. The sagger 3 containing the nano-powder is placed on the pusher plate 2. As the pusher plate 2 moves, the powder passes through the preheating section 101, the calcination section 102, and the cooling section 103 in sequence within the kiln cavity 104. The pushing assembly is located at one end of the track. The pushing assembly uses a long-stroke hydraulic rod installed outside the kiln body 1. The hydraulic rod can provide a stable and controllable thrust, pushing the pusher plate 2 to move smoothly on the track, ensuring the smooth transport of nano-alumina powder within the kiln.

[0028] The heating assembly is responsible for providing the heat required for the firing of nano-alumina powder. It includes a mixed gas pipeline 4 located at the top of the kiln body 1, which is connected to a gas inlet pipe 6 and a combustion air blower 11. This pipeline can fully mix the gas and combustion air to provide good conditions for combustion. Multiple rows of gas pipes 9 are vertically arranged in the kiln cavity 104 and are connected to the mixed gas pipeline 4 located at the top of the kiln body 1 via connecting pipes 5. The mixed gas pipeline 4 delivers combustible mixed gas into the gas pipes 9. The lower middle part of the gas pipes 9 is equipped with vertically evenly distributed burners 8, which face the passing sagger 3 to ensure that heat can be directly transferred to the sagger 3 to heat the nano-alumina powder. The gas pipes 9 are evenly distributed in the calcination section 102 of the kiln cavity 104. Multiple rows of gas pipes 9 are distributed in a matrix or staggered manner in the calcination section 102. The distance between the flue gas connecting pipes 5 in each row of gas pipes 9 is no more than 30cm. This layout allows the burner 8 to cover the transverse cross section inside the kiln body 1 as a whole, eliminating the injection blind zone and ensuring that the nano alumina powder in each position inside the kiln can be heated evenly.

[0029] The temperature control component is the core part for achieving precise temperature control. It includes temperature detectors, control units, and execution units. Multiple temperature detectors are distributed within the kiln cavity 104. Their function is to monitor the temperature information of the preheating section 101, calcination section 102, and cooling section 103 in real time and feed this information back to the control unit in a timely manner. Based on the temperature data fed back by the temperature detectors, the control unit accurately judges the temperature conditions of each section in the kiln and then controls the execution unit to adjust the heat output power of the burner 8. The execution unit includes an electromagnetic flow valve 7 installed on the connecting pipe 5, a gas valve 10 installed on the gas pipe 9, and a combustion fan 11. By adjusting the electromagnetic flow valve 7 and the gas valve 10, the flow rate of the gas can be controlled, and the air volume of the combustion fan 11 can be adjusted at the same time, thereby achieving precise adjustment of the heat output power of the burner 8 and ensuring that the temperature inside the kiln is always maintained within the range required for the firing of nano-alumina powder.

[0030] Multiple saggers 3 are stacked on the pusher plate 2. To ensure heating efficiency, a gas pipe 9 is provided on at least one side of each sagger 3, and the edge of each sagger 3 is no more than 20cm from the nearest burner 8. This allows the nano-alumina powder inside the sagger 3 to fully absorb heat, improving firing efficiency and quality. The burner 8 is a ceramic burner 8, which has advantages such as high temperature resistance and corrosion resistance, enabling it to work stably in high-temperature environments and ensuring the service life and heat output stability of the burner 8.

[0031] The alumina powder sintering process is as follows:

[0032] The sagger 3 containing nano-alumina powder is stacked on the pusher plate 2 according to the design requirements to ensure that the position of the sagger 3 is accurate and that it does not collide with the gas pipe 9 and the burner 8 when it moves in the kiln cavity 104, and that the distance between the sagger 3 and the gas pipe 9 and the burner 8 meets the requirements.

[0033] Start the equipment and push the component drive plate 2 to move along the track. The sagger 3 passes through the preheating section 101, the calcination section 102 and the cooling section 103 in sequence. In the preheating section 101, the residual heat of the calcination section 102 is used to preheat the nano alumina powder.

[0034] In the calcination section 102, the burner 8 sprays flames to heat the nano-alumina powder in the sagger 3. The temperature detector monitors the temperature in real time, and the control unit adjusts the execution unit according to the temperature feedback information to ensure that the calcination temperature is stable within a suitable range.

[0035] In the cooling section 103, the nano-alumina powder is gradually cooled. The length design of the cooling section 103 ensures the cooling effect, enabling the powder to reach a suitable discharge temperature.

[0036] After firing, pusher plate 2 sends the fired nano-alumina powder out of kiln body 1 for further processing.

[0037] Example 1

[0038] In this embodiment, combined with Figure 2 As shown, the heating assembly adopts a three-row gas pipe 9 structure design. Inside the kiln cavity 104, along the longitudinal direction of the kiln cavity 104, a row of gas pipes 9 is set in the middle position, and two other rows of gas pipes 9 are symmetrically set on the sides, with the middle row of gas pipes 9 as the axis of symmetry; four rows of saggers 3 are placed on the push plate 2. These saggers 3 are stacked in two groups. The arrangement of each group of saggers 3 is that the two rows of saggers 3 are adjacent, parallel and closely arranged. The two groups of saggers 3 are distributed on the push plate 2 along the width direction of the push plate 2; gas pipes 9 are set on the side of each row of saggers 3. This layout allows each row of saggers 3 to receive heat from the burner 8 of the gas pipe 9 at a relatively close distance, ensuring that the nano-alumina powder in the saggers 3 can be heated evenly during the firing process;

[0039] Example 2

[0040] In this embodiment, refer to Figure 3 As shown, the heating assembly adopts a structure of five rows of gas pipes 9. These five rows of gas pipes 9 are evenly distributed along the longitudinal direction of the kiln cavity 104, and the spacing between them is the same. On the push plate 2 of the conveying assembly, five rows of saggers 3 are placed. These saggers 3 are stacked at intervals, that is, each row of saggers 3 maintains a certain interval distance, and each row of saggers 3 is located between two adjacent gas pipes 9. This layout makes the distance between the saggers 3 and the gas pipes 9 and the burners 8 relatively uniform in all directions, so that the heat from the burners 8 can be absorbed more fully and comprehensively.

[0041] When the pusher plate 2 carries the five rows of saggers 3 into the calcination section 102, each row of saggers 3 is uniformly heated by the burners 8 from the gas pipes 9 on both sides during the movement. The ceramic burners 8 continuously and stably provide heat to the saggers 3. The temperature detector monitors the temperature in real time and feeds it back to the control unit. Based on the temperature feedback information, the control unit adjusts the electromagnetic flow valve 7, the gas valve 10 and the combustion fan 11 in the execution unit to achieve precise control of the heat output power of the burners 8, ensuring that the nano alumina powder completes the firing process in an ideal temperature environment, thereby improving the quality and stability of the product.

[0042] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A pusher plate (2) kiln for calcining alumina powder, characterized in that, include: Kiln body (1), kiln cavity (104) is arranged along its longitudinal direction in the kiln body (1), the kiln cavity (104) is arranged in the following order from the inlet to the outlet: preheating section (101), calcination section (102) and cooling section (103). The conveying assembly includes a track fixedly installed at the bottom of the kiln cavity (104), a pusher plate (2) movably installed on the track, a sagger (3) containing nano-powder placed on the pusher plate (2), and a pushing assembly provided at one end of the track. The pushing assembly drives the pusher plate (2) to pass through the preheating section (101), calcination section (102) and cooling section (103) along the track in sequence. The heating assembly includes a mixed gas pipeline (4) disposed at the top of the kiln body (1) and multiple rows of gas pipes (9) disposed in the kiln cavity (104). The mixed gas pipeline (4) is connected to a gas inlet pipe (6) and a combustion fan (11). The gas pipes (9) are vertically disposed in the kiln cavity (104) and installed at the top of the kiln body (1). The mixed gas pipeline (4) is connected to the gas pipes (9) through a connecting pipe (5) and delivers combustible mixed gas into the gas pipes (9). The lower part of the gas pipes (9) is provided with vertically evenly distributed burners (8), which face the passing sagger (3). The temperature control component includes a temperature detector, a control unit, and an execution unit. Multiple temperature detectors are installed in the kiln cavity (104) and feed back the temperature information of the preheating section (101), the calcination section (102), and the cooling section (103) to the control unit. The control unit controls the execution unit to adjust the heat output power of the burner (8) according to the temperature information fed back by the temperature detectors. The gas pipes (9) are evenly distributed in the calcination section (102) of the kiln cavity (104). Multiple rows of gas pipes (9) are distributed in a matrix or staggered manner in the calcination section (102). The distance between the flue gas connecting pipes (5) in each row of gas pipes (9) is no more than 30cm, so that the burner (8) can cover the transverse section inside the kiln body (1) without any injection blind spots.

2. The pusher plate (2) kiln for calcining alumina powder according to claim 1, characterized in that, Multiple saggers (3) are stacked on the push plate (2), and at least one side of the sagger (3) is provided with the gas pipe (9) and the edge of the sagger (3) is no more than 20 cm away from the nearest burner (8).

3. The pusher plate (2) kiln for calcining alumina powder according to claim 1, characterized in that, The burner (8) is a ceramic burner (8).

4. The pusher plate (2) kiln for calcining alumina powder according to claim 1, characterized in that, The execution unit includes an electromagnetic flow valve (7) installed on the connecting pipe (5), a gas valve (10) installed on the gas pipe (9), and a combustion-supporting blower (11).

5. The pusher plate (2) kiln for calcining alumina powder according to claim 2, characterized in that, Three rows of gas pipes (9) are arranged on the push plate (2), and the stacked saggers (3) are located between the gas pipes (9).

6. The pusher plate (2) kiln for calcining alumina powder according to claim 1, characterized in that, The pushing component is a long-stroke hydraulic rod disposed outside the kiln body (1), which pushes the push plate (2) to move on the track.

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