A blast furnace burden surface three-dimensional imaging system

Abstract

The application discloses a blast furnace charge level three-dimensional imaging system, comprising: a terahertz laser transceiver unit, a reflection scanning unit and a data acquisition and processing unit; the reflection scanning unit comprises a rotatable reflection module, a driving member and a controller; the scanned charge level receives the terahertz light waves reflected by the rotatable reflection module and reflects the terahertz light wave echoes; the driving member is connected to the rotatable reflection module and drives the reflection module to rotate in a first plane and a second plane, thereby respectively realizing first linear scanning of the length direction of the scanned charge level along a first direction axis and second linear scanning of the length direction along a direction perpendicular to the first direction axis; the controller controls the driving member to drive the rotatable emission module to rotate and complete overall scanning of the measured charge level; and the data acquisition and processing unit acquires the terahertz light wave echo signals, calculates the three-dimensional space coordinates of the measured charge level and constructs a three-dimensional image. The system can accurately detect the overall shape of the charge level in the furnace.

Description

Technical Field

[0001] This invention relates to the field of iron and steel smelting technology, and more specifically, to a three-dimensional imaging system for blast furnace charge surfaces. Background Technology

[0002] Reducing blast furnace fuel consumption is of great significance to promoting the development of the steel industry. The blast furnace is a key piece of equipment in the steel production process, and it is also a major source of energy consumption and pollution. Ensuring the stable, smooth, and efficient production of blast furnaces is related to the production efficiency of the steel industry and even the economic benefits of the entire society.

[0003] The distribution of the burden inside the blast furnace is one of the important factors affecting the furnace condition. Abnormal furnace conditions can lead to a decrease in production efficiency and product quality, or even a shutdown. For blast furnace operators, it is necessary to understand and control the shape of the burden inside the blast furnace in order to improve the energy utilization rate and the airflow distribution. Therefore, studying the burden distribution is an important measure to reduce the occurrence of abnormalities, improve work efficiency, and save energy and reduce emissions. However, the blast furnace is a closed reaction vessel for smelting pig iron under high temperature and high pressure conditions. Its internal environment is very complex and its working conditions are variable.

[0004] Existing methods for detecting blast furnace burden height mainly include mechanical probes, radar burden gauges, laser burden gauges, ultrasonic detectors, gamma-ray detectors, and infrared imagers. Traditional mechanical probes are the primary tool for detecting burden height, with multiple sets typically installed in the blast furnace for multi-point detection. However, this method cannot perform continuous measurements, has limited installation options, requires significant maintenance, incurs high repair costs, and suffers from large measurement errors. Radar detection devices are complex and bulky, often requiring multiple radars to operate in conjunction, and are expensive. Laser detection has strong imaging capabilities during shutdown periods, but struggles to penetrate dust in heavily dusty environments. Ultrasonic detectors are suitable for constant temperature and pressure conditions, but the high temperature and pressure of a blast furnace result in poor detection performance. Gamma-ray detectors offer high measurement accuracy, but the device itself poses certain risks and is unsuitable for locations with many workers. Infrared imagers are significantly affected by temperature and dust, which can impact the system's resolution.

[0005] The current methods for detecting blast furnace burden have certain limitations and need to be improved. Summary of the Invention

[0006] The present invention provides a three-dimensional imaging system for blast furnace burden surface, which overcomes at least one problem existing in the prior art.

[0007] This specification provides an embodiment of a three-dimensional imaging system for blast furnace burden, including: a terahertz laser transceiver unit, a reflection scanning unit, and a data acquisition and processing unit;

[0008] The terahertz laser transceiver unit is configured to emit terahertz light waves;

[0009] The reflection scanning unit includes a rotatable reflection module, a driving component, and a controller;

[0010] The rotatable reflective module is configured to direct the terahertz light wave emitted by the terahertz laser transceiver unit onto the surface to be scanned, so that the surface to be scanned receives the terahertz light wave and reflects the terahertz light wave echo.

[0011] The terahertz laser transceiver unit is also configured to receive the terahertz light wave echo;

[0012] The driving component is connected to the rotatable reflective module. The driving component is configured to drive the rotatable reflective module to rotate in a first plane. The rotation angle is within a first preset angle range. The terahertz light wave is reflected by the rotatable reflective module and then emitted to the scanned material surface, thereby realizing a first linear scan of the length direction of the scanned material surface along the first axial direction.

[0013] The driving component is also configured to drive the rotatable reflective module to rotate in the second plane, with the rotation angle within a second preset angle range. The terahertz light wave is reflected by the rotatable reflective module and then emitted onto the scanned material surface, thereby achieving a second linear scan of the length direction of the scanned material surface along the second directional axis; the first directional axis and the second directional axis are perpendicular to each other.

[0014] The controller is connected to the drive unit and is configured to control the drive unit to drive the rotatable transmitting module to rotate according to a preset instruction until the entire surface of the material being measured is scanned.

[0015] The data acquisition and processing unit is configured to acquire the terahertz light wave echo signal and obtain the three-dimensional spatial coordinates of the measured material surface based on the terahertz light wave echo signal, thereby constructing a three-dimensional image of the measured material surface based on the three-dimensional spatial coordinates.

[0016] Optionally, the data acquisition and processing unit is configured to acquire the terahertz light echo signal and obtain the three-dimensional spatial coordinates of the measured material surface based on the terahertz light echo signal, specifically including:

[0017] With the first direction axis as the X-axis and the second direction axis as the Y-axis, the origin is the point where the reflected light wave after being reflected by the rotatable reflective module approaches the inner wall of the blast furnace and is perpendicularly incident on the measured material surface along the second direction axis. "Approaching" means that the distance between the reflected light wave and the inner wall of the blast furnace in the first direction axis direction is within a preset distance value range. At this time, the terahertz light wave emitted by the terahertz laser transceiver unit is incident horizontally on the rotatable reflective module, and the angle between the reflection point of the rotatable reflective module and both the first and second direction axes is 45 degrees.

[0018] The first rotation angle corresponding to the rotatable reflective module rotating in the first plane is β, and the second rotation angle corresponding to the rotatable reflective module rotating in the second plane is γ. The distance from the light spot on the material surface to the reflection point of the rotatable reflective module is L. Then, the three-dimensional coordinates of the current material surface position are calculated according to Formula 1, Formula 2, and Formula 3, respectively.

[0019] X = L*sin2β (1);

[0020] Y = L*sin2γ (2);

[0021]

[0022] Optionally, the reflective scanning unit includes an electrically controlled rotating mechanism, a mechanical base, a flexible rod, and a gold-plated reflector.

[0023] The gold-plated reflector is connected to the mechanical base via the flexible rod; the electrically controlled rotating mechanism drives the flexible rod to rotate the gold-plated reflector in the first plane and the second plane, respectively realizing a first linear scan of the length direction of the scanned material surface along the first directional axis and a second linear scan of the length direction along the second directional axis.

[0024] Optionally, the terahertz laser transceiver unit is mounted on the mechanical base, which is also provided with an emission port for terahertz light waves to pass through.

[0025] Optionally, the terahertz laser transceiver unit is a terahertz radar transceiver integrated device, and the data acquisition and processing unit is configured to obtain the distance from the light spot on the material surface to the reflection point of the rotatable reflective module based on the terahertz light wave echo signal and the terahertz radar ranging principle.

[0026] Optionally, the terahertz radar transceiver is a 0.2 terahertz pulse radar.

[0027] Optionally, the number of flexible rods is four.

[0028] Optionally, the transmission center of the 0.2 terahertz pulse radar is collinear with the center of the gold-plated reflector.

[0029] Optionally, the blast furnace material surface three-dimensional imaging system further includes: an image drawing unit; the image drawing unit is configured to draw a three-dimensional image of the measured material surface based on the three-dimensional spatial coordinates.

[0030] Optionally, the blast furnace burden surface three-dimensional imaging system further includes: an image display unit; the image display unit is configured to display a three-dimensional image of the measured burden surface.

[0031] The embodiments in this specification use terahertz waves to detect the material surface inside the furnace. The excellent penetrability of terahertz waves can accurately detect the shape of the material surface, and it is less affected by the dusty environment. At the same time, it has better resolution than other microwaves, and can accurately detect the internal conditions of the blast furnace in harsh blast furnace environments.

[0032] Compared with the prior art, the inventive points of the embodiments in this specification include at least:

[0033] 1. This invention uses terahertz light waves to detect the material surface inside the furnace. Terahertz light waves have better penetration and resolution for dust, and can detect more accurate information about the material surface inside the blast furnace. This is one of the inventive points of this invention.

[0034] 2. This system does not require the installation of multiple radar scanning devices. It only requires a terahertz laser transceiver unit in conjunction with a reflection scanning device, which rotates in two perpendicular directions. Each rotation angle corresponds to a point on the blast furnace material surface, and the terahertz light wave scans the material surface under test at different angles, realizing the overall scanning of the material surface under test. This helps to reconstruct the scanned two-dimensional image into a three-dimensional image. The system is simple in structure, low in cost, easy to install, and convenient for later maintenance, which is one of the inventive points of this invention. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the composition of a three-dimensional imaging system for blast furnace burden surface according to an embodiment of the present invention;

[0037] Figure 2 This is a schematic diagram of the structure of a reflection scanning unit according to an embodiment of the present invention;

[0038] Figure 3This is a schematic diagram illustrating the calculation process of the three-dimensional coordinates of the current material surface position according to an embodiment of the present invention. Detailed Implementation

[0039] 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.

[0040] It should be noted that the terms "comprising" and "having," and any variations thereof, in the embodiments and drawings of this specification are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices.

[0041] This specification discloses a three-dimensional imaging system for blast furnace burden surfaces. The following is a detailed description. Figure 1 As shown, the blast furnace burden surface three-dimensional imaging system 10 includes:

[0042] Terahertz laser transceiver unit 101, reflection scanning unit 102, and data acquisition and processing unit 103;

[0043] The terahertz laser transceiver unit is configured to emit terahertz light waves;

[0044] The reflection scanning unit includes a rotatable reflection module 1021, a drive unit 1022, and a controller 1023;

[0045] The rotatable reflective module is configured to direct the terahertz light wave emitted by the terahertz laser transceiver unit onto the surface to be scanned, so that the surface to be scanned receives the terahertz light wave and reflects the terahertz light wave echo.

[0046] The terahertz laser transceiver unit is also configured to receive the terahertz light wave echo;

[0047] The driving component is connected to the rotatable reflective module. The driving component is configured to drive the rotatable reflective module to rotate in a first plane. The rotation angle is within a first preset angle range. The terahertz light wave is reflected by the rotatable reflective module and then emitted to the scanned material surface, thereby realizing a first linear scan of the length direction of the scanned material surface along the first axial direction.

[0048] The driving component is also configured to drive the rotatable reflective module to rotate in the second plane, with the rotation angle within a second preset angle range. The terahertz light wave is reflected by the rotatable reflective module and then emitted onto the scanned material surface, thereby achieving a second linear scan of the length direction of the scanned material surface along the second directional axis; the first directional axis and the second directional axis are perpendicular to each other.

[0049] The controller is connected to the drive unit and is configured to control the drive unit to drive the rotatable transmitting module to rotate according to a preset instruction until the entire surface of the material being measured is scanned.

[0050] The data acquisition and processing unit is configured to acquire the terahertz light wave echo signal and obtain the three-dimensional spatial coordinates of the measured material surface based on the terahertz light wave echo signal, thereby constructing a three-dimensional image of the measured material surface based on the three-dimensional spatial coordinates.

[0051] The rotatable reflective module can rotate in two perpendicular directions. The rotation range can be the minimum rotation angle, which can be set according to requirements. Each rotation angle corresponds to a point on the blast furnace material surface. Rotation in two perpendicular directions can scan the entire material surface.

[0052] The invention utilizes terahertz waves to detect the material surface inside the furnace. Terahertz waves have excellent penetrability, which allows for accurate detection of the material surface shape. They are less affected by dusty environments and have better resolution compared to other microwaves. This allows for accurate detection of the internal conditions of the blast furnace in harsh environments, which is one of the inventive points of this invention.

[0053] In one implementation, the controller controls the driving component to drive the rotatable reflective module to rotate, thereby completing the scanning of the overall surface distribution of the material being measured. Specific steps may include:

[0054] Terahertz light waves are incident on the reflective component of a rotatable reflective module. The reflective component effectively reflects the terahertz light waves. After the light path is deflected by the reflective component, the light waves are incident on the surface of the blast furnace. The controller controls the rotatable reflective module, or at least the reflective component, to rotate within a first plane, causing the light waves to scan a straight line across the surface of the blast furnace. The length of this straight line is along a first directional axis, such as the X-axis. Then, the controller controls the rotatable reflective module, or at least the reflective component, to rotate within a second plane, causing the light waves to scan across the surface of the blast furnace. A new straight line is drawn, with its length along a second directional axis, such as the Y-axis. The first and second directional axes are perpendicular to each other. After scanning a certain distance along the Y-axis, a rotatable reflective module, or at least a controlled reflective component, rotates again within the first plane, causing the light wave to scan a straight line across the blast furnace surface. The length of this new straight line is along the opposite direction of the first directional axis, such as the opposite direction of the X-axis. Each rotation in the opposite direction by an angle performs at least one scan along the Y-axis. After multiple cycles, the terahertz laser can complete the scanning of the entire blast furnace surface distribution. In summary, the scanning method in this implementation first scans a straight line along the X-axis, the length of which corresponds to the length of the blast furnace surface along the X-axis. Then, it scans cyclically along the direction perpendicular to this straight line, i.e., continuously scanning along the Y-axis until a complete scan of the surface is completed.

[0055] In one implementation, the controller controls the driving component to drive the rotatable reflective module to rotate, thereby completing the scanning of the overall surface distribution of the material being measured. Specific steps may include:

[0056] Terahertz light waves are incident on the reflective component of a rotatable reflective module. The reflective component effectively reflects the terahertz light waves. After the light path is deflected by the reflective component, the light waves are incident on the surface of the blast furnace. The controller controls the rotatable reflective module, or at least the reflective component, to rotate within a first plane, causing the light waves to scan a straight line across the surface of the blast furnace. The length of this line is along a first directional axis, such as the X-axis. Simultaneously, at least one scan along the Y-axis is performed on each scanning point along the X-axis. After multiple cycles, the overall distribution of the terahertz light waves across the blast furnace surface can be scanned. In summary, the scanning method in this implementation involves scanning forward along the X-axis while simultaneously scanning along the Y-axis until the entire surface of the blast furnace is scanned.

[0057] Both of the above scanning methods can scan the furnace material surface in a two-dimensional space based on the X and Y axes using terahertz light waves. Compared to CCD imaging technology, terahertz light waves can still accurately image even during blasting when there is a lot of dust. In addition, the above two scanning methods are not simply line scans in one dimension. By combining scanning in two dimensions, it is more conducive to reflecting the overall structure of the material surface. Furthermore, with this system, there is no need to install multiple radars inside the blast furnace for scanning. Only one terahertz transceiver unit and a reflection scanning unit are needed to scan the material surface from two dimensions. The system equipment is simple in composition, easy to install, and easier to maintain. In addition, the data acquisition and processing unit of this system can also calculate the distance between the material surface and the light wave reflection point. Combined with parameters such as the rotation angle of the rotatable reflection module, the three-dimensional coordinates of each point on the furnace material surface can be calculated, thereby achieving the purpose of three-dimensional imaging based on three-dimensional coordinates. The above points are all inventive points of this invention.

[0058] In one implementation, the data acquisition and processing unit is configured to acquire the terahertz light echo signal and obtain the three-dimensional spatial coordinates of the measured material surface based on the terahertz light echo signal, specifically including:

[0059] With the first direction axis as the X-axis and the second direction axis as the Y-axis, the origin is the point where the reflected light wave after being reflected by the rotatable reflective module approaches the inner wall of the blast furnace and is perpendicularly incident on the measured material surface along the second direction axis. "Approaching" means that the distance between the reflected light wave and the inner wall of the blast furnace in the first direction axis direction is within a preset distance value range. At this time, the terahertz light wave emitted by the terahertz laser transceiver unit is incident horizontally on the rotatable reflective module, and the angle between the reflection point of the rotatable reflective module and both the first and second direction axes is 45 degrees.

[0060] The first rotation angle corresponding to the rotatable reflective module rotating in the first plane is β, and the second rotation angle corresponding to the rotatable reflective module rotating in the second plane is γ. The distance from the light spot on the material surface to the reflection point of the rotatable reflective module is L. Then, the three-dimensional coordinates of the current material surface position are calculated according to Formula 1, Formula 2, and Formula 3, respectively.

[0061] X = L*sin2β (1);

[0062] Y = L*sin2γ (2);

[0063]

[0064] In one implementation, see [link to implementation details]. Figure 2 , Figure 2A schematic diagram of a reflective scanning unit is shown, which includes an electrically controlled rotating mechanism, a mechanical base 201, a flexible rod 202, and a gold-plated reflector 203.

[0065] The gold-plated reflector is connected to the mechanical base via the flexible rod; the electrically controlled rotating mechanism drives the flexible rod to rotate the gold-plated reflector in the first plane and the second plane, respectively realizing a first linear scan of the length direction of the scanned material surface along the first directional axis and a second linear scan of the length direction along the second directional axis.

[0066] During the charging phase, combustion has not yet begun inside the blast furnace, and the furnace temperature is not high. A through-hole is provided on the side wall of the blast furnace top. The 3D imaging system for the blast furnace charge surface is installed at the through-hole location. During installation, stability and installation angle are considered to ensure that the terahertz waves, after being reflected by the mirror, can scan the entire charge surface. See also... Figure 3 , Figure 3 This diagram illustrates the calculation process of the three-dimensional coordinates of the current material surface position. The origin is defined as the point where the reflected light strikes the material surface perpendicularly to the furnace wall. The incident light enters horizontally, and the angles between the reflector and both the X-axis and Y-axis are 45°. During the reflector's rotation and scanning process, the horizontal rotation angle is β, and the vertical rotation angle is γ (due to...). Figure 3 It is a floor plan, so Figure 3 Only β is shown in the diagram (γ is not shown). The distance from the light spot on the material surface to the reflector is denoted as L. The three spatial coordinates of the material surface are obtained as (X,Y,Z)=(L*sin2β,L*sin2γ, A three-dimensional image of the material surface can be generated based on these three-dimensional coordinates.

[0067] In one implementation, the terahertz laser transceiver unit is mounted on the mechanical base, and the mechanical base is also provided with an emission port 204 for terahertz light waves to pass through.

[0068] In one implementation, the terahertz laser transceiver unit is a terahertz radar transceiver integrated device 205, and the data acquisition and processing unit is configured to obtain the distance from the light spot on the material surface to the reflection point of the rotatable reflective module based on the terahertz light wave echo signal and the terahertz radar ranging principle.

[0069] In one implementation, the terahertz radar transceiver is a 0.2 terahertz pulse radar.

[0070] Currently, during blast furnace shutdown periods, the dust particle size and concentration are relatively small, allowing conventional lidar to penetrate and image the material. However, during blast furnace blowing periods, the environment transforms into a heavy dust environment, where ordinary lidar is insufficient. Terahertz lasers, on the other hand, can image the material in the harsh furnace environment. In China, the particle size of pulverized coal injected into the furnace is mainly distributed below 150μm, accounting for approximately 99%. Traditionally, the proportion of particles smaller than 74μm needs to be maintained at 70%–80%, while particles larger than 355μm are almost nonexistent. Therefore, a 0.2 terahertz pulse radar can be selected, ensuring good penetration of the terahertz radar into the dust during blast furnace blowing periods. Furthermore, it offers better resolution compared to microwaves, allowing for more accurate detection of the material surface information inside the blast furnace.

[0071] Optionally, the number of flexible rods is four.

[0072] The terahertz radar transceiver unit is integrated with the mechanical base. The reflector is connected to the mechanical base through four flexible rods. By driving the flexible rods, the reflector can be rotated in both the X and Y axes, resulting in a stable structure.

[0073] To further improve the stability of the reflective scanning structure, in one implementation, the transmission center of the 0.2 terahertz pulse radar is collinear with the center of the gold-plated reflector. This collinear arrangement helps to make the equipment used during the scanning process more stable and less prone to tilting or jitter.

[0074] In one implementation, the blast furnace burden surface three-dimensional imaging system further includes: an image drawing unit; the image drawing unit is configured to draw a three-dimensional image of the measured burden surface based on the three-dimensional spatial coordinates.

[0075] In one implementation, the blast furnace burden surface three-dimensional imaging system further includes: an image display unit; the image display unit is configured to display a three-dimensional image of the measured burden surface.

[0076] Terahertz radar reflectors emit terahertz light waves, which are reflected by the reflectors and reach the blast furnace burden surface. The reflected light echoes are received by a terahertz light wave receiving system, which converts the light intensity into an electrical signal using a terahertz detector. This electrical signal is acquired by a data acquisition card and transmitted to a computer. The computer's data processing software calculates the burden surface height based on the echo information corresponding to the electrical signal. After a series of software processing algorithms, a visual three-dimensional image of the burden surface distribution is finally generated, accurately reflecting changes in the burden surface within the blast furnace.

[0077] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of one embodiment, and the modules or processes shown in the drawings are not necessarily essential for implementing the present invention.

[0078] Those skilled in the art will understand that the modules in the apparatus of the embodiments can be distributed in the apparatus of the embodiments as described in the embodiments, or they can be located in one or more devices different from this embodiment with corresponding changes. The modules of the above embodiments can be combined into one module, or they can be further divided into multiple sub-modules.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A three-dimensional imaging system for blast furnace burden surface, characterized in that, include: Terahertz laser transceiver unit, reflection scanning unit, and data acquisition and processing unit; The terahertz laser transceiver unit is configured to emit terahertz light waves; The reflection scanning unit includes a rotatable reflection module, a driving component, and a controller; The rotatable reflective module is configured to direct the terahertz light wave emitted by the terahertz laser transceiver unit onto the surface to be scanned, so that the surface to be scanned receives the terahertz light wave and reflects the terahertz light wave echo. The terahertz laser transceiver unit is also configured to receive the terahertz light wave echo; The driving component is connected to the rotatable reflective module. The driving component is configured to drive the rotatable reflective module to rotate in a first plane. The rotation angle is within a first preset angle range. The terahertz light wave is reflected by the rotatable reflective module and then emitted to the scanned material surface, thereby realizing a first linear scan of the length direction of the scanned material surface along the first axial direction. The driving component is also configured to drive the rotatable reflective module to rotate in the second plane, with the rotation angle within a second preset angle range. The terahertz light wave is reflected by the rotatable reflective module and then emitted onto the scanned material surface, thereby achieving a second linear scan of the length direction of the scanned material surface along the second directional axis; the first directional axis and the second directional axis are perpendicular to each other. The controller is connected to the drive unit and is configured to control the drive unit to drive the rotatable transmitting module to rotate according to a preset instruction until the entire surface of the material being measured is scanned. The data acquisition and processing unit is configured to acquire the terahertz light wave echo signal and obtain the three-dimensional spatial coordinates of the measured material surface based on the terahertz light wave echo signal, thereby constructing a three-dimensional image of the measured material surface based on the three-dimensional spatial coordinates.

2. The three-dimensional imaging system for blast furnace burden surface according to claim 1, characterized in that, The data acquisition and processing unit is configured to acquire the terahertz light echo signal and obtain the three-dimensional spatial coordinates of the measured material surface based on the terahertz light echo signal, specifically including: With the first direction axis as the X-axis and the second direction axis as the Y-axis, the origin is the point where the reflected light wave after being reflected by the rotatable reflective module approaches the inner wall of the blast furnace and is perpendicularly incident on the measured material surface along the second direction axis. "Approaching" means that the distance between the reflected light wave and the inner wall of the blast furnace in the first direction axis direction is within a preset distance value range. At this time, the terahertz light wave emitted by the terahertz laser transceiver unit is incident horizontally on the rotatable reflective module, and the angle between the reflection point of the rotatable reflective module and both the first and second direction axes is 45 degrees. The first rotation angle corresponding to the rotatable reflective module rotating in the first plane is β, and the second rotation angle corresponding to the rotatable reflective module rotating in the second plane is γ. The distance from the light spot on the material surface to the reflection point of the rotatable reflective module is L. Then, the three-dimensional coordinates (X, Y, Z) of the current material surface position are calculated according to Formula 1, Formula 2, and Formula 3, respectively. X = L*sin2β (1); Y = L*sin2γ (2); 3. The three-dimensional imaging system for blast furnace burden surface according to claim 2, characterized in that, The reflective scanning unit includes an electrically controlled rotating mechanism, a mechanical base, a flexible rod, and a gold-plated reflector. The gold-plated reflector is connected to the mechanical base via the flexible rod; the electrically controlled rotating mechanism drives the flexible rod to rotate the gold-plated reflector in the first plane and the second plane, respectively realizing a first linear scan of the length direction of the scanned material surface along the first directional axis and a second linear scan of the length direction along the second directional axis.

4. The three-dimensional imaging system for blast furnace burden surface according to claim 3, characterized in that, The terahertz laser transceiver unit is mounted on the mechanical base, which is also provided with an emission port for terahertz light waves to pass through.

5. The three-dimensional imaging system for blast furnace burden surface according to claim 4, characterized in that, The terahertz laser transceiver unit is a terahertz radar transceiver integrated device. The data acquisition and processing unit is configured to obtain the distance from the light spot on the material surface to the reflection point of the rotatable reflection module based on the terahertz light wave echo signal and the terahertz radar ranging principle.

6. The three-dimensional imaging system for blast furnace burden surface according to claim 5, characterized in that, The terahertz radar transceiver is a 0.2 terahertz pulse radar.

7. The three-dimensional imaging system for blast furnace burden surface according to claim 6, characterized in that, The number of flexible rods is four.

8. The three-dimensional imaging system for blast furnace burden surface according to claim 7, characterized in that, The transmission center of the 0.2 terahertz pulse radar is collinear with the center of the gold-plated reflector.

9. The three-dimensional imaging system for blast furnace burden surface according to claim 8, characterized in that, Also includes: Image drawing unit; The image rendering unit is configured to render a three-dimensional image of the measured material surface based on the three-dimensional spatial coordinates.

10. The three-dimensional imaging system for blast furnace burden surface according to any one of claims 1 to 9, characterized in that, Also includes: An image display unit is configured to display a three-dimensional image of the measured material surface.

Images