CN108827169A - A kind of rotary hearth furnace furnace high-temperature pelletizing feed layer thickness detection device - Google Patents

Abstract

The invention discloses a detection device for the thickness of a high-temperature pellet material layer in a rotary hearth furnace, aiming to solve the problem that the excessive thickness of the bottom material layer affects production efficiency. tube, pneumatic advance and retreat device, electric control cabinet, air source box, controller and man-machine interface, the outer protective sleeve, industrial camera and electric control cabinet are respectively connected with the air source box; the industrial camera, controller respectively connected with the electric control cabinet. The invention uses a pneumatic advance and retreat device to control the industrial camera on the outer protection sleeve to monitor the change of the thickness of the furnace bottom material layer in real time, and solves the problem that the melted high-temperature pellets increase the thickness of the furnace bottom material layer and cause the interruption of the entire production process. At the same time, it can effectively Reduce downtime, reduce waste of materials and energy, improve production efficiency, prevent accidents, and achieve the purpose of saving energy and reducing consumption.

Description

A device for detecting the thickness of high-temperature pellet material layer in a rotary hearth furnace

technical field

The invention relates to the field of recycling and control of iron-containing solid waste, in particular, the invention relates to a device for detecting the thickness of a high-temperature pellet material layer in a rotary hearth furnace.

Background technique

The existing rotary hearth furnace process is mainly used for treating zinc-containing iron-containing solid waste in iron and steel enterprises, extracting zinc from raw materials, and obtaining metallized pellets at the same time. Various dusts and binders in the batching bin are mixed according to the proportion, pressed into balls and dried, and then sent to the distributor of the rotary hearth furnace, and the materials are evenly distributed on the annular hearth of the rotary hearth furnace. The drying balls entering the rotary hearth furnace use the high temperature of about 1250-1300 ℃ in the furnace and the carbon in the pellets to produce a reduction reaction. Within 20 minutes to 30 minutes, most of the iron oxide is reduced to metallic iron; at the same time, the zinc oxide is reduced to zinc, and the zinc volatilizes into the flue gas, and is reoxidized into zinc oxide powder, which settles and is finally recovered.

In the actual production of the rotary hearth furnace, there will be a problem of accumulation of material at the bottom of the furnace. This is because the material enters the hearth of the rotary hearth furnace and passes through the heating zone, the first reduction zone, the second reduction zone, the third reduction zone and the discharge zone ( The heating zone is about 1100 degrees, the first reduction zone is about 1250 degrees, the second reduction zone is about 1280 degrees, the maximum temperature of the third reduction zone is about 1290 degrees, and the lowest temperature of the discharge area is about 850 degrees) and other different temperature sections rotate once and then discharge When the screw machine is discharged, the powder mixed or damaged in the pellets is easy to melt and harden on the hearth first. At the same time, it is impossible for the pellets to be discharged out of the furnace at the discharge spiral after one revolution, and some of them will be in the furnace. The furnace rotates repeatedly, and finally the high temperature melts and hardens on the bottom of the furnace, which gradually increases the thickness of the bottom material layer, and finally causes the entire hearth to first touch the water-cooled partition wall, resulting in the hearth being unable to rotate and affecting the smooth progress of production. If this phenomenon occurs, the only solution now is to stop the furnace and cool down. It takes a long time to cool down. When the temperature drops to a suitable temperature, the water-cooled partition wall and water-cooled cover are removed, and the operator uses a pick to pry the large hardened material into small pieces. This method is time-consuming and labor-intensive. It takes 3 to 5 days to process the whole process, which seriously affects continuous production, greatly reduces the operating rate, affects the life of furnace refractory materials, and wastes a lot of pellets. materials.

Contents of the invention

In order to solve the problem that the production efficiency is affected by the excessive thickness of the furnace bottom material layer, the invention provides a detection device for the thickness of the high-temperature pellet material layer in the rotary hearth furnace.

In order to achieve the above object, the present invention provides a detection device for the thickness of the high-temperature pellet material layer in the rotary hearth furnace, which includes the furnace wall of the rotary hearth furnace, an industrial camera for collecting the signal of the thickness of the furnace bottom material layer, and a device that runs through the rotary hearth furnace. The outer protective sleeve of the wall used to protect the industrial camera, the pneumatic advance and retreat device connected to the industrial camera for sending the industrial camera into or out of the outer protective sleeve, and the The cooling air source required by the industrial camera or the pneumatic air source required by the pneumatic advance and retreat device is used to filter, regulate and detect the pressure of the air source, and an electric control cabinet that sends an alarm signal in the event of an air failure failure, and is used to provide the air source The gas source box, the controller used to obtain the thickness of the furnace bottom material layer according to the collected furnace bottom material layer thickness signal and the man-machine interface connected with the controller, the outer protective sleeve, industrial camera and electric control cabinet are respectively connected with the air source box; the industrial camera and the controller are respectively connected with the electric control cabinet.

Preferably, the outer protective sleeve is cylindrical, and the outer protective sleeve is made of stainless steel and superalloy materials.

Preferably, the pneumatic advance and retreat device includes an air cylinder and a solenoid valve for controlling the working state of the air cylinder, and the air cylinder is connected with the air source box.

Preferably, the industrial camera model is a MER-G-P series digital camera.

Compared with the prior art, a device for detecting the thickness of the high-temperature pellet material layer in the rotary hearth furnace of the present invention has the following beneficial effects:

The invention discloses a detection device for the thickness of the high-temperature pellet material layer in the rotary hearth furnace, which controls the industrial camera on the outer protection sleeve through the pneumatic advance and retreat device to monitor the change of the thickness of the furnace bottom material layer in real time, and solves the problem that the melted high-temperature pellets make the furnace bottom material The increase of layer thickness leads to the interruption of the entire production process. At the same time, it can effectively reduce downtime, reduce waste of materials and energy, improve production efficiency, prevent accidents, and achieve the purpose of saving energy and reducing consumption.

Additional aspects and advantages of the invention will be set forth in part in the description which follows, and will become apparent from the description, or may be learned by practice of the invention.

Description of drawings

The above and/or additional aspects and advantages of the present invention will become apparent and easy to understand from the following description of the embodiments in conjunction with the accompanying drawings, wherein:

Fig. 1 is a schematic diagram of the overall structure of a high-temperature pellet layer thickness detection device in a rotary hearth furnace according to an embodiment of the present invention;

Figure 2 is a schematic diagram of the principle of pinhole imaging;

Fig. 3 is a schematic diagram of industrial camera measurement of a high-temperature pellet layer thickness detection device in a rotary hearth furnace according to an embodiment of the present invention.

Instructions for identification in the figure:

1. Rotary hearth furnace wall; 2. Outer protective sleeve; 3. Pneumatic advance and retreat device; 4. Industrial camera; 5. Electric control cabinet; 6. Gas source box; 7. Controller; 8. Human-machine interface.

Detailed ways

Embodiments of the present invention are described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numerals designate the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the figures are exemplary only for explaining the present invention and should not be construed as limiting the present invention.

Please refer to Fig. 1 , a device for detecting the thickness of high-temperature pellet material layer in a rotary hearth furnace according to an embodiment of the present invention, which includes a rotary hearth furnace wall 1, an industrial camera 4 for collecting the signal of the thickness of the furnace bottom material layer, a penetrating rotary The outer protective sleeve 2 used to protect the industrial camera 4 of the bottom furnace wall 1, the pneumatic advancing and retreating device 3 connected to the industrial camera 4 for sending the industrial camera 4 into or out of the outer protective sleeve 2, and the The cooling air source required by the industrial camera 4 and the pneumatic air source required by the pneumatic advance and retreat device 3 are filtered, regulated, and the pressure of the air source is detected, and the electric control cabinet 5 that sends an alarm signal in the event of an air failure occurs. The gas source box 6 of the source, the controller 7 used to obtain the thickness of the furnace bottom material layer according to the collected furnace bottom material layer thickness signal and the man-machine interface 8 connected with the controller 7, wherein, the outer protective sleeve 2, the industrial camera 4 and the electric control cabinet 5 are respectively connected with the air source box 6; the industrial camera 4 and the controller 7 are connected with the electric control cabinet 5 respectively.

The outer protective sleeve 2 is a double-layer structure cylinder made of high-quality stainless steel and super alloy materials, which uses air cooling to protect the industrial camera 4, and is sealed with nitrogen purge for self-cleaning.

The pneumatic advance and retreat device 3 includes a cylinder and a solenoid valve, and the pneumatic advance and retreat device 3 controls the advance and retreat of the industrial camera 4 through the principle of pneumatic force.

For example, when the compressed air pressure is lower than the set value or the temperature of the high-temperature optical lens exceeds the set value, the industrial camera 4 can be automatically withdrawn from the furnace to protect the safety of the probe.

Industrial camera 4 is a high-resolution industrial camera, which captures the distance traveled by a specific furnace bottom material layer area in a certain period of time in real time, and obtains the progress of the furnace bottom material layer area in the image through image recognition technology. The pixel distance, which generates a furnace bottom material layer thickness signal, is sent to the controller 7 for analysis and processing.

In some embodiments, the model of the industrial camera is a MER-G-P series digital camera.

Please refer to Fig. 2, the controller 7 in the embodiment of the present invention measures the distance through the principle of pinhole imaging, wherein, the principle of pinhole imaging is shown in Fig. 2:

Based on the basic principles of applied optics, the length D of the target, the length d of the target on the image plane, the distance L between the camera and the target, and the focal length f of the camera satisfy the following relationship:

Among them, the focal length f of the industrial camera 4 is easily measured experimentally, and the length of the target on the image plane is calculated by the above formula

Wherein, N and L ₀ are the pixel resolution and target surface length of the industrial camera 4 respectively, which are known quantities. n is the pixel length of the target on the image plane, which can be obtained by tracking the moving distance of the bottom material layer target on the image plane within a specified time by means of image recognition. And the actual distance that the furnace bottom material layer target moves within the specified time is

L＝V ₀ t (3)

Among them, V ₀ is the moving speed of the furnace bottom material layer, and t is the specified time.

Please refer to Fig. 3, Fig. 3 has shown the industrial camera 4 measurement schematic diagram of a kind of high-temperature pellet material layer thickness detection device in the rotary hearth furnace furnace of the embodiment of the present invention, wherein, the angle of industrial camera 4 is α, distance from furnace bottom material The top of the layer is h, and the distance from the bottom is H, therefore, the following geometric relationship can be obtained

h=Lsinα (4)

Therefore, the thickness of the furnace bottom material layer is

x=H-h (5)

Combining the above formulas (1)-(5), the thickness of the furnace bottom material layer can be obtained, so that the controller 7 can calculate the distance from the industrial camera 4 to the target area by applying the small hole imaging principle in optics, and finally through the industrial camera The position angle of 4 calculates the height from the industrial camera 4 to the furnace bottom material layer, and finally reverses the height of the furnace bottom material layer.

In some implementations, if it is found that the furnace bottom material layer increases close to 50% of the top of the partition wall, the production personnel can stop the material according to the detection data, and after the normal materials in the furnace are discharged, raise the furnace temperature and reverse the bottom For the furnace, use the discharge spiral to scrape the furnace floor, discharge the increased hardened material in time after melting, reduce the thickness of the hearth bottom material layer, and then feed the material for production. Through this detection device, downtime can be reduced, waste of materials and energy can be reduced, production operation rate can be improved, accidents can be prevented, and the purpose of energy saving and consumption reduction can be achieved.

Compared with the prior art, a device for detecting the thickness of the bottom material layer of the high-temperature pellet furnace in the rotary hearth furnace according to the embodiment of the present invention has the following beneficial effects:

An embodiment of the present invention is a detection device for the thickness of the bottom material layer of high-temperature pellets in a rotary hearth furnace. The pneumatic advance and retreat device 3 controls the industrial camera 4 on the outer protective sleeve 2 to monitor the change of the thickness of the furnace bottom material layer in real time, and solve the problem of melting. High-temperature pellets increase the thickness of the furnace bottom material layer and cause the interruption of the entire production process. At the same time, it can effectively reduce downtime, reduce waste of materials and energy, improve production efficiency, prevent accidents, and achieve the purpose of saving energy and reducing consumption.

The above descriptions are only part of the embodiments of the present invention. It should be pointed out that those skilled in the art can make some improvements and modifications without departing from the principles of the present invention. It should be regarded as the protection scope of the present invention.

Claims (4)

1. A device for detecting the thickness of the high-temperature pellet layer in a rotary hearth furnace, characterized in that the device for detecting the thickness of the high-temperature pellet layer in the rotary hearth furnace comprises a rotary hearth furnace wall for collecting bottom material An industrial camera for layer thickness signals, an outer protective sleeve for protecting the industrial camera through the furnace wall of the rotary hearth furnace, and an outer protective sleeve for sending the industrial camera into or out of the outer protective sleeve and connected with the The pneumatic advance and retreat device connected to the industrial camera is used to filter, regulate and detect the air source pressure for the cooling air source required by the industrial camera or the pneumatic air source required by the pneumatic advance and retreat device, and when there is a gas failure An electric control cabinet that sends an alarm signal at any time, a gas source box for providing gas source, a controller for obtaining the thickness of the furnace bottom material layer according to the collected furnace bottom material layer thickness signal, and a man-machine interface connected with the controller , the outer protective sleeve, the industrial camera and the electric control cabinet are respectively connected to the air source box; the industrial camera and the controller are respectively connected to the electric control cabinet. 2. The device for detecting the thickness of the high-temperature pellet material layer in the rotary hearth furnace according to claim 1, wherein the outer protective sleeve is cylindrical, and the outer protective sleeve is made of stainless steel and superalloy materials. to make. 3. The device for detecting the thickness of the high-temperature pellet material layer in the rotary hearth furnace according to claim 1, wherein the pneumatic advance and retreat device includes a cylinder and a solenoid valve for controlling the working state of the cylinder, and the cylinder and the cylinder are connected to each other. The air source box is connected. 4. The device for detecting the thickness of the high-temperature pellet layer in the rotary hearth furnace according to claim 1, wherein the industrial camera model is a MER-G-P series digital camera.