Vertical continuous calcination furnace for activated alumina balls

Abstract

The present invention discloses a vertical continuous calcination furnace for activated alumina balls, which comprises a vertical furnace body. The top of the furnace body is a feed inlet, and the bottom is a discharge outlet. A hot air distributor is installed in the middle of the vertical furnace body. The hot air distributor is provided with a number of air distribution holes, and the hot air distributor is connected to a burner. The burner provides hot air for the interior of the vertical furnace body through the hot air distributor. An air extraction port is provided at the top of the vertical furnace body, and the air extraction port is connected to an induced draft fan. The hot air enters downward from the middle and lower part of the furnace body and turns back upward under the action of the induced draft fan to heat the balls.

Description

Technical Field

[0001] The present invention relates to a calcination device for activated alumina, specifically a vertical calcination furnace. Background Art

[0002] Calcination is the last and most crucial process in the processing of activated alumina balls. The stable calcination temperature directly affects the quality stability and adsorption capacity of activated alumina balls. For the alumina balls to be calcined with high density and uniformity, it is not only crucial for the rolling forming of the disc pelletizing, but also affected by factors such as powder, additives, calcination temperature and time, pressure, and calcination atmosphere. Currently, most of the existing activated alumina calcination furnaces are horizontal calcination furnaces. The alumina balls are manually loaded onto trays, and the trays are placed on tray racks. After all are loaded, the furnace door of the calcination furnace is opened, and the tray rack together with the trays is put into the shell, then the furnace door is closed, and the feeding process is completed. Then, the burner is ignited for incineration. The degree of equipment automation is low, and most of them cannot achieve continuous production, with low production efficiency and difficult to meet the requirements of the production process.

[0003] Although a vertical calcination furnace specifically for the production and processing of activated alumina balls is disclosed in Patent CN202020786831.7, the air inlet pipe of this vertical calcination furnace is sent downward from the top of the vertical calcination furnace to the bottom position of the furnace body. The calcination temperature of the alumina balls close to the air inlet pipe will rise sharply, and the finished product rate of the alumina balls will decrease due to overheating; at the same time, scaling will occur at the place of the raw material bin in the upper part of the vertical furnace and the feeding port of the vertical furnace, affecting the feeding. Summary of the Invention

[0004] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a vertical continuous calcination furnace for activated alumina balls. This device improves the existing vertical continuous calcination furnace from multiple angles. This device can uniformly calcine the alumina balls, can achieve automatic feeding and simultaneously drying and cooling, and the entire production process can be carried out continuously with high production efficiency.

[0005] In order to achieve the above purpose, the present invention is realized through the following technical solutions:

[0006] The vertical continuous calcination furnace for activated alumina balls proposed by the present invention includes a vertical furnace body. The top of the furnace body is the feeding port, and the bottom is the discharging port. A hot air distributor is installed in the middle of the vertical furnace body. The hot air distributor is provided with a number of air distribution holes. The hot air distributor is connected to a burner, and the burner provides hot air for the inside of the vertical furnace body through the hot air distributor. An air extraction port is provided at the top of the vertical furnace body, and the air extraction port is connected to an induced draft fan. The hot air enters downward from the middle and lower part of the furnace body and turns back upward under the action of the induced draft fan to heat the spheres.

[0007] As a further technical solution, the vertical furnace body includes an upper furnace body and a lower furnace body. The top of the hot air distributor is connected to the upper furnace body, and the bottom is connected to the lower furnace body.

[0008] As a further technical solution, the hot air distributor includes a cylinder with a certain height. The top of the cylinder is fixedly connected to the bottom of the upper furnace body, and the bottom of the cylinder is fixedly connected to the top of the lower furnace body. Along the height direction of the cylinder, a circle of air inlet pipes is provided on the outer side wall at the middle position of the cylinder. Air inlets are provided on the air inlet pipes, and communication holes are provided on the inner side wall of the cylinder. The communication holes are connected to a plurality of hot air distribution pipes arranged vertically and horizontally, and a number of hot air outlets are provided on the hot air distribution pipes.

[0009] As a further technical solution, the air inlets are connected to the burner through air supply pipes.

[0010] As a further technical solution, there is also a circle of return material skirt on the inner side wall of the cylinder, and the return material skirt is located below the connection position of the hot air distribution pipes arranged vertically and horizontally and the cylinder.

[0011] As a further technical solution, a number of air distribution holes are arranged in a staggered manner around the straight wall of the vertical furnace body corresponding to the air inlet pipes to prevent uneven roasting of the wall-attached materials.

[0012] As a further technical solution, a cloth cone is provided at the bottom of the vertical furnace body.

[0013] As a further technical solution, an inverted cone-shaped chassis is installed at the bottom of the vertical furnace body. A vibrating discharge channel is installed at the bottom of the inverted cone-shaped chassis, and a discharge valve is installed on the discharge channel. The discharge valve is connected to the control system.

[0014] As a further technical solution, the feed inlet is connected to the upper feed bin, and the upper feed bin is connected to the automatic feeding device.

[0015] As a further technical solution, temperature sensors are provided at the burner outlet, the air inlet, and the roasting zone of the furnace body. The air intake of the burner is interlocked with the temperature sensor at the burner outlet to control the set requirement of the outlet temperature; the temperature sensor in the roasting zone of the vertical furnace is interlocked with the discharge valve at the discharge port of the vertical furnace to control the feeding amount of the vertical furnace; the temperature sensor at the air inlet of the vertical furnace is connected to the alarm. When the exhaust temperature rises, the alarm gives an alarm.

[0016] The beneficial effects of the above embodiments of the present invention are as follows:

[0017] In the present invention, a hot air distributor is arranged at the middle position of the furnace body, so that hot air enters downward from the middle and lower part of the furnace body, and under the action of the induced draft fan, turns back upward to heat the spheres, realizing uniform roasting of alumina spheres according to the roasting heating curve. At the same time, the present invention realizes the anti-caking and anti-blocking treatment of the feeding port at the top of the upper furnace body. Scaling will occur at the place where the raw material bin at the upper part of the vertical furnace and the feeding port of the vertical furnace due to material discharging, which affects the feeding. The specific solution of the present invention is to reduce the temperature difference. The hot air drawn up by the above-mentioned induced draft fan reduces the temperature difference between the feeding port at the top of the upper furnace body and the inside of the furnace body, and also reduces the temperature difference between the material bin and the feeding port, thereby solving the problem of scaling. By arranging the induced draft fan at the air inlet, a large amount of water vapor generated during the roasting process is drawn out by the induced draft fan and will not condense into water droplets at the upper end inside the furnace body, thus avoiding scaling and affecting the feeding. Moreover, a purification buffer tank can be arranged at the air inlet, so that the water droplets condense in the purification buffer tank.

[0018] At the same time, the present invention improves the fluidity of alumina spheres by arranging a bottom cloth cone of the furnace. Under the action of the cloth cone, the gaps between the spheres are made uniform through flowing, and combined with the hot air distributor, the spheres can be uniformly heated during the roasting process, greatly improving the product qualification rate.

[0019] The whole set of equipment is equipped with automatic feeding and automatic discharging; the intake gas volume of the gas is interlocked with the thermocouple at the outlet temperature of the burner to control the set requirement of the outlet temperature; the thermocouple in the roasting zone of the vertical furnace is interlocked with the discharge valve at the discharge port of the vertical furnace to control the discharging amount of the vertical furnace. A thermocouple is arranged at the air inlet of the vertical furnace, and the thermocouple is connected with an alarm. When the exhaust temperature rises, the alarm gives an alarm. The automation control level is high, greatly improving the production efficiency. Brief Description of the Drawings

[0020] The specification drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0021] Figure 1 is the overall structural schematic diagram of the present invention;

[0022] Figure 2 is the structural schematic diagram of the present invention connecting the hot air burner;

[0023] Figure 3 is the top view of the connection state between the hot air distributor and the hot air burner of the present invention;

[0024] Figure 4 is the structural schematic diagram of the hot air distributor;

[0025] Figure 5 is Figure 6 the A-A sectional view of

[0026] Figure 6 is Figure 6 the B-B cross-sectional view of;

[0027] Figure 7 is Figure 6 the I-placement schematic diagram in;

[0028] Figure 8 is Figure 7 the C-C cross-sectional view of;

[0029] Figure 9 is the structural schematic diagram of the furnace body mounting frame;

[0030] Figure 10 is the structural schematic diagram of the furnace body structure and the hot air distributor;

[0031] In the figure: 1 material bin, 2 railing, 3 platform, 4 air inlet, 5 observation port, 6 furnace body, 7 hot air distributor, 8 cloth cone, 9 inverted cone-shaped chassis, 10 discharge pipe, 11 mounting frame, 12 burner, 13 air supply pipe, 14 air supply pipe, 7-1 cylinder body, 7-1-1 hole, 7-2 air inlet pipe, 7-3 hot air distribution pipe, 7-4 return material skirt. Detailed implementation manners

[0032] It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0033] It should be noted that the terms used herein are only for describing specific implementation manners and are not intended to limit the exemplary implementation manners of the present invention. As used herein, unless the present invention otherwise clearly indicates, the singular forms are also intended to include the plural forms. In addition, it should also be understood that when the terms "include" and / or "comprise" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof;

[0034] Term explanation section: Terms such as "installation", "connection", "coupling", "fixation", etc. in the present invention should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral body; it can be a mechanical connection, an electrical connection, a direct connection, or an indirect connection through an intermediate medium. It can be an internal connection between two components, or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] As introduced in the background art, there are deficiencies in the prior art. To solve the above technical problems, the present invention proposes a vertical continuous roasting furnace for activated alumina balls.

[0036] In a typical embodiment of the present invention, as Figure 1 shown, the vertical continuous calcination furnace for activated alumina balls disclosed in this embodiment includes a vertical furnace body. A conical chassis is installed at the bottom of the furnace body. There is a vibrating feeding device with a conical chassis at the bottom of the furnace body. A discharge pipe is installed at the discharge port of the conical chassis, and a discharge valve is installed on the discharge pipe. An air inlet pipe is arranged in the middle and lower part of the furnace body. Air distribution holes are provided on the hot air distributor, and the air distribution holes communicate with the air inlet pipe. The air inlet pipe communicates with the burner. Heat exchange air holes, a feeding port and an observation hole are arranged at the top of the furnace body. The heat exchange air holes are connected to an induced draft fan. The feeding port is connected to an upper feeding bin.

[0037] Specifically, the diameter of the furnace body in this embodiment is about 1000 - 1200 mm, and the height is 4800 - 5100 mm. The furnace body includes two upper and lower parts, namely the upper furnace body 6 - 2 and the lower furnace body 6 - 1. The upper furnace body 6 - 2 is installed on the upper support 6 - 4, and the lower furnace body 6 - 1 is installed on the lower support 6 - 3. Both the upper support 6 - 4 and the lower support 6 - 3 are connected to the calcination furnace mounting frame 11, realizing the fixation of the entire furnace body on the calcination furnace mounting frame 11.

[0038] Furthermore, the structure of the mounting frame 11 is as Figure 9 shown. It includes four columns, and there is a platform 3 at the top. Railings 2 are arranged around the platform 3. The feed bin 1 is fixed on the platform 3, and the bottom of the feed bin 1 communicates with the feeding port at the top of the upper furnace body.

[0039] Furthermore, a hot air distributor 7 is fixed between the upper furnace body 6 - 2 and the lower furnace body 6 - 1. The material of the hot air distributor is 310S stainless steel with a thickness of 8 mm. The hot air distributor 7 includes a cylinder 7 - 1 with a certain height. The top of the cylinder 7 - 1 is fixedly connected to the bottom of the upper furnace body, and the bottom of the cylinder 7 - 1 is fixedly connected to the top of the lower furnace body. Along the height direction of the cylinder, a circle of air inlet pipes 7 - 2 is opened on the outer side wall at the middle position of the cylinder. There are two air inlets on the air inlet pipe 7 - 2, and communication holes are opened on the inner side wall of the cylinder. The communication holes are connected to a plurality of hot air distribution pipes 7 - 3 arranged vertically and horizontally. A number of hot air outlets are provided on the hot air distribution pipes 7 - 3.

[0040] Furthermore, the above two air inlets are connected to the hot air burner 12 through two air supply pipes. The air volume at the outlet of the hot air burner is about 3000 - 4500 m³, and is sent into the hot air distributor 7 of the furnace body through 2 air supply pipes 13 and air supply pipe 14, and then enters the hot air distribution pipe 7 - 3 to uniformly exchange with the material.

[0041] Further, there is also a return material skirt 7-4 on the inner side wall of the cylinder. The slope of the return material skirt 7-4 is about 10 degrees, and the return material skirt 7-4 is located below the connection position of the hot air distribution pipe arranged horizontally and vertically and the cylinder.

[0042] Further, in this embodiment, the opening area of the hot air distribution pipe 7-3 is 90% of the cross-sectional area of the air supply pipe 13. Generally, it is required that the area ratio of the two does not exceed 100%, so that the hot air has a certain resistance, which can improve the uniformity of the hot air outlet.

[0043] Further, small holes are staggeredly opened around the vertical furnace straight wall corresponding to the air inlet pipe 7-2. The diameter of each small hole is approximately about 10 mm. The purpose of setting these small holes is also to introduce hot air to prevent uneven roasting of the wall-attached materials. And these small holes are located on the vertical furnace wall below the hot air distribution pipe arranged horizontally and vertically.

[0044] Further, a feed inlet is provided at the top of the upper furnace body 6-2. The feed inlet is connected to the feed bin 1 for feeding. At the same time, there are also air inlets 4 and observation holes 5 on both sides of the feed inlet at the top of the upper furnace body. The air inlet 4 is connected to an induced draft fan. The induced draft fan at the top of the furnace body is a negative pressure high-head fan. The air volume can be set to 4000-5000 m³, the head is 17000-18000, and the motor power is 15-20 kW; the shell and blades of the induced draft fan are made of stainless steel.

[0045] Further, anti-caking and anti-blocking treatment is carried out at the feed inlet at the top of the upper furnace body. Scaling will occur at the place where the raw material bin in the upper part of the vertical furnace and the feed inlet of the vertical furnace during feeding, which affects feeding. The specific solution is to reduce the temperature difference. The hot air drawn up by the above-mentioned induced draft fan reduces the temperature difference between the feed inlet at the top of the upper furnace body and the inside of the furnace body, and reduces the temperature difference between the feed bin and the feed inlet, thereby solving the problem of scaling. At the same time, a treatment port is reserved at the connection, and manual treatment can be carried out through the treatment port.

[0046] Further, the air inlet 4 is connected to the tail gas discharge pipe. The diameter of the tail gas discharge pipe is 400 cm, the thickness is 1.5 mm, and the downward slope is 5%. The interface is a flexible connection. The tail gas discharge pipe is connected to a purification buffer tank, and the purification buffer tank is connected to the induced draft fan. After heating the product, the tail gas contains 30-40% water vapor with a small amount of material dust. The condensed water in the exhaust gas is settled through the buffer tank and then enters the induced draft fan.

[0047] Furthermore, for burner control, the maximum fuel consumption of the burner is 65 m³ / hour, and it meets the requirements of automatic control and interlock for intake air volume and burner outlet temperature adjustment. Gas storage vertical burner: Calculated based on an air volume of over 4000 and a temperature of 560 - 750 °C, the diameter of the gas storage vertical burner is 800 mm, and the height is 1500 - 1800 mm. It is lined with refractory bricks (temperature resistance 1300 °C) and externally insulated with FBT, with an FBT thickness of 8 - 10 mm. The outlet temperature is controlled, and the outlet temperature is automatically interlocked and controlled in three units, equipped with natural gas leakage protection.

[0048] Furthermore, at the bottom of the lower furnace body, there is a forwardly arranged cloth cone with an angle of 60 degrees, which is connected to the inner wall of the lower furnace body through a cloth cone support plate. There is a gap of 5 - 6 mm between the bottom straight edge of the cloth cone and the vertical wall of the vertical furnace, and the material is 3105. The cloth cone and the vertical wall of the vertical furnace are supported and connected at three points and fixed. By setting the cloth cone at the furnace bottom, the fluidity of alumina balls is improved under the action of the cloth cone. Through the flow, the gaps between the balls are made uniform, and combined with the hot air distributor, the balls can be evenly heated during the roasting process, greatly improving the product qualification rate.

[0049] Furthermore, an inverted cone-shaped chassis is installed at the bottom of the vertical furnace body. A vibrating discharge channel is installed at the bottom of the inverted cone-shaped chassis, and a discharge valve is installed on the discharge channel. The taper of the inverted cone-shaped chassis is 60 degrees, and the bottom of the inverted cone-shaped chassis is a discharge pipe with a diameter of 100 cm and a length of 500 cm; the temperature difference controlled by the inverted cone-shaped chassis is ±5 °C.

[0050] Furthermore, the outlet of the vertical furnace can also recover the waste heat of temperature reduction. A circular pipe with a diameter of 50 mm is made on the inverted cone-shaped chassis of the vertical furnace to form a circular closed intake air pipeline, equipped with air distribution and an intake air valve, one for each equal direction, to control the air volume, achieve the purpose of cooling the material, and at the same time recover and utilize the waste heat.

[0051] Furthermore, a vibratory feeder is also installed on the discharge pipe. The vibratory feeder is connected to a frequency converter, and the frequency converter is interlocked with the p908X control module.

[0052] Furthermore, the silo of the vertical furnace is made: with a diameter of 1.3 m and a height of 1.5 m. The upper cover is added with a cross-shaped bottom, reinforced to bear a weight of 0.8 tons, and a feed inlet with a diameter of 350 mm is opened at the center of the cover.

[0053] Furthermore, the thermocouple settings of the furnace body are as follows: 1. A thermocouple is installed at the air inlet of the vertical furnace to measure the exhaust gas temperature, and the air inlet is used as the exhaust outlet; 2. A thermocouple is set in the preheating zone of the furnace body, and the preheating zone is 0.8 m above the center of the feed inlet; 3. A thermocouple is set in the roasting zone of the furnace body, and the roasting zone is 0.8 m below the center of the feed inlet. 4. A thermocouple is set at the air outlet of the burner to measure the outlet air temperature.

[0054] Furthermore, the control mode of the automatic control part of the vertical continuous calcination furnace for activated alumina balls is as follows:

[0055] 1. The gas volume of the burner is interlocked with the thermocouple at the outlet temperature of the burner to control the set requirement of the outlet temperature.

[0056] 2. The thermocouple in the calcination zone of the vertical furnace is interlocked with the discharging device of the vertical furnace to control the feeding amount of the vertical furnace.

[0057] 3. A temperature rise alarm is set for the thermocouple at the air inlet of the vertical furnace, and an alarm is given when the temperature is higher than the set temperature.

[0058] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. Vertical continuous calcination furnace for activated alumina balls, comprising a vertical furnace body, with a feed inlet at the top of the furnace body and a discharge outlet at the bottom, characterized in that, A hot air distributor is installed in the middle of the vertical furnace body. The hot air distributor is provided with a number of air distribution holes. The hot air distributor is connected to a burner, and the burner provides hot air for the inside of the vertical furnace body through the hot air distributor. On both sides of the feed inlet at the top of the vertical furnace body, air intake openings are provided, and the air intake openings are connected to an induced draft fan. The hot air enters from the middle and lower part of the furnace body downward and turns back upward under the action of the induced draft fan to heat the sphere. The vertical furnace body includes an upper furnace body and a lower furnace body. The top of the hot air distributor is connected to the upper furnace body, and the bottom is connected to the lower furnace body. A cloth cone is provided at the bottom of the vertical furnace body. The hot air distributor includes a cylinder with a certain height. The top of the cylinder is fixedly connected to the bottom of the upper furnace body, and the bottom of the cylinder is fixedly connected to the top of the lower furnace body. Along the height direction of the cylinder, a circle of air inlet pipes is provided on the outer side wall at the middle position of the cylinder. Air inlet openings are provided on the air inlet pipes, and communication holes are provided on the inner side wall of the cylinder. The communication holes are connected to a plurality of hot air distribution pipes arranged vertically and horizontally. A number of hot air outlets are provided on the hot air distribution pipes. There is also a circle of return material skirt on the inner side wall of the cylinder, and the return material skirt is located below the connection position of the hot air distribution pipes arranged vertically and horizontally and the cylinder.

2. The vertical continuous calcination furnace for activated alumina balls according to claim 1, wherein The air inlet opening is connected to the burner through an air supply pipeline.

3. The vertical continuous calcination furnace for activated alumina balls according to claim 1, characterized in that A number of air distribution holes are arranged in a staggered manner around the straight wall of the vertical furnace body corresponding to the air inlet pipe.

4. The vertical continuous calcination furnace for activated alumina balls as described in claim 1, characterized in that, An inverted cone-shaped chassis is installed at the bottom of the vertical furnace body. A vibrating discharge channel is installed at the bottom of the inverted cone-shaped chassis, and a discharge valve is installed on the discharge channel.

5. The vertical continuous calcination furnace for activated alumina balls according to claim 1, characterized in that, The feed inlet is connected to a feeding bin.

6. The vertical continuous calcination furnace for activated alumina balls according to claim 1, characterized in that, Temperature sensors are provided at the burner outlet, the air intake opening, and the roasting zone of the furnace body. The intake air volume of the burner is interlocked with the temperature sensor at the burner outlet to control the set requirement of the outlet temperature; the temperature sensor in the roasting zone of the vertical furnace is interlocked with the discharge valve at the discharge outlet of the vertical furnace to control the feeding amount of the vertical furnace; the temperature sensor at the air intake opening of the vertical furnace is connected to an alarm. When the exhaust temperature rises, the alarm gives an alarm.

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