System for judging slag discharge end point of pyrometallurgical furnace

Abstract

The invention discloses a system for judging a slag discharge end point of a pyrometallurgical furnace, and relates to the technical field of pyrometallurgy, in particular to a method for capturing necessary spectral information in a non-immersion and remote mode, providing real-time information of operation conditions capable of being used for process decision making, quantifying the proportion of each phase in a system view field by utilizing analysis software, and determining the slag discharge end point of the pyrometallurgical furnace. And according to a threshold value defined by a user, the proper time for stopping deslagging is determined by analyzing the change of the carrying-out quantity of the target element. By measuring the percentage of one phase in the other phase, control over copper loss caused by deslagging is improved, the recovery rate of copper is increased, and the tank cleaning time is shortened, so that the maintenance cost is reduced, manual sampling at a deslagging opening is reduced to the maximum extent, the safety of workers is improved, and the time for operators to make contact with smelting gas is shortened.

Description

Technical Field

[0001] The invention relates to the technical field of pyrometallurgy, in particular to a system for judging the end point of slag discharge in a pyrometallurgical furnace. Background Art

[0002] Pyrometallurgy is a branch of metallurgical technology. The extraction and refining of metals is mainly completed by heat energy, so it is called pyrometallurgy. This process starts with sulfide ore; due to the large particle size of the ore, in order to obtain the copper embedded in it, the ore must be crushed until it reaches an average of 1 / 2 inch per particle, and then ground into 0.18 mm fine powder, and then concentrated by flotation to obtain copper concentrate composed of iron and copper sulfides, the main components of which are chalcopyrite (CuFeS2) and pyrite (FeS2), and the copper grade is about 25%.

[0003] Most sulfide copper concentrates are smelted by pyrometallurgical processes, and after smelting, blowing, refining and slag depletion, the copper content reaches 99% purity in the anode furnace. In the above process, the copper concentrate is melted and oxidized at a temperature of 1250°C. Due to the stronger affinity of oxygen with iron and sulfur, three phases are formed in the molten pool:

[0004] Copper matte or white matte (sulphide phase with 45-75% copper grade);

[0005] · Slag, a separate molten phase of iron and silicon oxides;

[0006] · A gas phase rich in sulfur dioxide (SO2).

[0007] The smelting oxidation reaction can be described by the following reaction formula:

[0008]

[0009] Where (Cu, Fe, S) corresponds to copper concentrate, and its oxidation reaction product FeO combines with SiO2 to form slag, which is separated from the rest of the products due to its lower density. The copper and sulfur in the concentrate form a miscible melt with FeS in the form of Cu2S, called matte or white matte. The copper content of matte depends on the amount of oxygen added to the smelting furnace. The amount of oxygen is high enough to desulfurize by forming SO2(g), but not too high to avoid copper oxidation.

[0010] The matte or white matte enters the converter (usually PS converter) to continue to oxidize the remaining S and Fe, and generate SO2, blowing slag and metallic copper Cu. The slag mainly floats on the surface with iron oxides, and below is a melt with a copper grade of about 98.5%, called blister copper.

[0011] Finally, in the anode furnace, the crude copper is first further oxidized and then reduced to reduce the concentrations of S and O in the melt to 50 and 1500 ppm respectively, thereby obtaining anode copper with a purity greater than 99%.

[0012] During the smelting process, the copper recovery rate reaches 98.5%; during the smelting and blowing stages, part of the metallic copper is often lost due to mechanical inclusions during the slag discharge process.

[0013] In addition, the pyrometallurgical industry, especially copper smelters, has a relatively harsh working environment, such as high-temperature operations, workers exposed to hot, dusty and high-concentration sulfur dioxide environments and projections of hot materials, large amounts of PM2.5 particulate materials, high concentrations of sulfur dioxide (g), etc. These factors make it difficult to install and use measuring instruments on site to monitor and control the separation process of slag and matte or copper; in addition, manual direct detection of the melt at the high-temperature slag outlet will also expose operators to dangerous environments such as skin burns or eye damage unnecessarily. The lack of such monitoring makes it impossible to accurately control the entrainment of copper during the slag discharge process.

[0014] Currently, there are a wide variety of new technologies being implemented in the pyrometallurgical industry, but overall, there has been little success in automated process monitoring and control. The material release operation process in the smelting industry is usually controlled by monitoring key operating indicators (laboratory composition chemical analysis, manual sampling, direct visual observation of the brightness of the molten phase by the operator, and mass balance). Operational control decisions are made based on these analyses; however, these analytical observations lack the accuracy and speed to make real-time decisions. The operator's emotional and psychological state and personal experience will also affect the final judgment, making it variable and uncertain.

[0015] A misjudgment or miscalculation by the operator of the end point of the slagging phase can lead to:

[0016] Copper recovery cycle time increased significantly;

[0017] Increased consumption of reducing agent (natural gas) during pyro-refining;

[0018] Increased operating costs;

[0019] Low quality of anode copper and risk of impurity transfer;

[0020] Shortened life of smelting furnace or converting furnace;

[0021] Increased workshop maintenance costs;

[0022] Metal loss due to copper carry-out;

[0023] Generate more recycled materials.

[0024] At present, the copper smelting industry has not yet developed a method that can detect the proportion of matte or white matte in the slag of smelting furnaces and slag depletion furnaces, nor has it developed a method that can detect the proportion of matte or white matte in converter slag discharge.

[0025] However, in the steel industry, the spectral information of pig iron (carbon-saturated hot metal) and slag during the blast furnace production process has been studied. The models in these studies describe parameters such as the characteristic spectrum of iron, casting depth and temperature, slag layer thickness, slag absorption coefficient and iron-slag interface reflectivity.

[0026] The method consists in identifying the higher spectral bands produced during casting, which can be recorded using a camera sensitive in the visible and near-infrared spectral range. A narrow-band filter centered at 650 nm is used to filter in this spectral range. The results confirm that the characteristic spectral differences between iron and slag at 650 nm allow the location of these phases to be spatially distinguished online. The instrument is mounted on the iron chute and detects the percentage of slag in the chute based on the changes in the electrical properties of the inductor. However, it cannot be directly applied to the copper industry because electrical instrument characterization of the phases is required at high temperatures and real-time visualization of the slag discharge process is not possible.

[0027] Similarly, the steel industry has developed electromagnetic and mechanical principles to determine the phase of the melt in the furnace. However, they require sensor arrays to be installed around the furnace to determine the phase and are therefore not suitable for measuring the phase during slag removal, nor can they provide detailed spatial images or continuous real-time sensor signals.

[0028] In addition, the steel industry has commercial instruments for online detection of slag (LAND Instruments). The instrument uses a narrowband filter centered on a wavelength of 3.7 μm to measure the infrared spectrum in the mid-frequency band (3-7 μm wavelength) to generate a video that clearly distinguishes steel from slag in the image. Associated with the device is an image pixel calculation formula to accurately quantify the percentage of slag in the steel within the system's field of view.

[0029] On the other hand, there is a commercial method based on spectral measurement for the control of non-ferrous metal pyrometallurgical process, called the optical production control (OPC) system. This technology determines the end point of blowing by capturing specific spectral information on the installed blowing furnace. OPC can estimate the percentage of Cu in white matte by monitoring the infrared spectra of PbS and PbO. The intensity changes of the spectra of these two substances characterize the reaction process in the furnace. It is worth noting that OPC requires a high-sensitivity, high-spectral resolution spectrometer, which is limited to fiber optic measurement and is therefore not suitable for accurate phase identification in the slag discharge area.

[0030] In view of the above, there is still a need to develop corresponding technologies to detect or manage the proportion of matte or white matte in the slag of smelting furnaces and depletion furnaces, or to detect the proportion of matte or white matte when deslagging in converters. Summary of the invention

[0031] The present invention provides a system for judging the end point of slag discharge in a pyrometallurgical furnace, which solves the problem that the prior art mentioned in the above background technology cannot judge the end point of the slag discharge process of the furnace.

[0032] The present invention provides the following technical solution: a system for judging the slag discharge endpoint of a pyrometallurgical furnace, comprising an outer cover, and also comprising a visual system, a computer, a cooling system, a power supply, a supporting structure and peripheral equipment; the visual system, the computer, the cooling system, the power supply and the peripheral equipment are all arranged on the outer cover, the visual system and the peripheral equipment are connected to the computer, the visual system, the computer and the cooling system are all connected to the power supply, the supporting structure is arranged outside the outer cover, and the supporting structure is used to support the outer cover;

[0033] The visual system is a multi-spectral visual system, including a camera and a tuned narrow-band filter, the tuned narrow-band filter is connected to the camera, the camera is connected to a computer, the image acquisition end of the visual system is located outside the outer cover, and the visual system is used to digitally integrate the filtered electromagnetic spectrum emitted by the melt out of the furnace and transmit it to the computer for processing;

[0034] The cooling system operates in a high temperature environment and is used to dissipate heat from internal components of the system so that the temperature of the internal components of the system remains within the operating range;

[0035] The power supply includes a voltage regulator, a battery and a charging module, and the power supply is used to supply power to the visual system, the computer and the cooling system;

[0036] The peripheral device is arranged outside the outer cover, and the operation interface of the peripheral device is provided with analysis software; the analysis software is used to quantify the proportion of each phase in the system field of view, and determine the appropriate time to stop slag discharge by analyzing the change of copper stripping amount according to the threshold value defined by the user, and generate an audio-visual alarm through the display and audio interface of the computer to indicate the stop of the slag discharge operation, and in addition, the digital signal indicating the end point of the slag discharge operation is transmitted to the control room via wired or wireless communication;

[0037] The analysis software includes an image acquisition module, a region of interest selection module, a pixel calculation module and a visualization module;

[0038] 1. Image acquisition module: used to digitize scene signals to generate useful data that can be processed;

[0039] Second, the region of interest selection module: used to obtain useful information from the acquired scene and identify the regions corresponding to the different objects under study;

[0040] 3. Pixel calculation module: used to estimate the area of ​​each phase in the slag discharge process in real time and generate its percentage indication;

[0041] 4. Visualization Module: Allows operators to visualize the slag removal process on the hardware interface screen, obtain real-time information about copper loss, view information on historical copper loss, and configure parameters such as image acquisition rate, allowed copper loss threshold, and activate and stop slag removal alarms.

[0042] Preferably, the visual system includes three cameras:

[0043] a) A reference camera using VISNIR technology;

[0044] b) a contrast-enhancing camera using VISNIR technology and equipped with a narrowband filter tuned to 1000 nm for distinguishing the phases of tapped white matte-slag, matte / white matte-slag in the electric furnace and matte-slag in the flash smelting furnace;

[0045] c) A contrast-enhancing camera using short-wave infrared (SWIR) technology with a narrow-band filter at 1560 nm for phase differentiation in the blister copper-matte discharge from the PS converter and the flash smelting furnace.

[0046] Preferably, each camera is connected to a focal length lens according to the distance between the camera and the slag discharge operation, and the field of view of the slag discharge process is adjusted to magnify and generate detailed and clear images within a safe distance.

[0047] Preferably, the cooling system operates at a temperature above 40°C.

[0048] Preferably, when in use, the measurement and slag discharge endpoint judgment system is pointed at the slag discharge chute of the furnace or converter at a distance of 5-30m to adjust the slag discharge field of view and generate an image of the material flowing through or out of the slag discharge chute.

[0049] Preferably, the analysis software uses silicon-based and indium gallium arsenide (InGaAs)-based sensors for VISNIR and SWIR band capture, and image capture is performed periodically, once every certain number of seconds, determined by the user.

[0050] Preferably, the measurement and slag discharge endpoint determination system captures necessary spectral information in a non-invasive and remote manner, providing real-time information on operating conditions that can be used for process decision making.

[0051] Preferably, the principle of the measurement and slag discharge endpoint judgment system is based on analyzing a series of slag discharge images, wherein the phase is identified by spectral comparison integrated by the vision system.

[0052] Compared with the prior art, the present invention has the following beneficial effects:

[0053] Improved control of copper loss from slag removal by determining the percentage of one phase in another;

[0054] Increased copper recovery rate;

[0055] Reduce tank cleaning time, thereby reducing maintenance costs;

[0056] Minimize manual sampling at the slag outlet to improve worker safety;

[0057] Reduce the time operators are exposed to smelting gases. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 It is a schematic diagram of the operating environment of the structure of the present invention;

[0059] Figure 2 Schematic diagram of a scaled-down laboratory experimental setup;

[0060] Figure 3 This is a comparison chart of the center wavelength of the filter tuned between white matte and slag phase;

[0061] Figure 4 This is a schematic diagram of the comparison between white matte and slag when the contrast value is 7.7 with the VISNIR camera without adding an optical filter;

[0062] Figure 5 This is a schematic diagram of the comparison between white matte and slag when the contrast ratio of the VISNIR camera is 9.6;

[0063] Figure 6 is a comparison of the center wavelengths of filters tuned between rough copper and matte phases;

[0064] Figure 7 This is a schematic diagram of the comparison between rough copper and matte copper when the contrast value is 26.1 with the VISNIR camera without adding an optical filter;

[0065] Figure 8 This is a schematic diagram of the comparison between rough copper and matte copper when the contrast value of the SWIR camera is 38.8;

[0066] Fig. 9 A three-dimensional schematic diagram of a system for judging the slag discharge endpoint of a pyrometallurgical furnace provided by the present invention;

[0067] Fig.10for Fig. 9 Front view schematic diagram;

[0068] Fig.11 for Fig. 9 Internal schematic diagram.

[0069] In the figure: 1. Visual system; 2. Computer; 3. Outer cover; 4. Cooling system; 5. Power supply; 6. Support structure; 7. Peripheral equipment; 8. Vertical electric furnace; 9. Quartz reaction tube; 10. Upper gas treatment inlet; 11. Lower gas treatment inlet; 12. Upper inlet; 13. Lower inlet; 14. Upper outlet; 15. Lower outlet; 16. Window; 17. Reaction tube; 18. Temperature indicator; 19. Thermocouple; 20. Silicon carbide resistor; 21. PID controller; 22. Nitrogen; 23. Quartz tube; 24. Sample; 25. Crucible; 26. Mechanical translator. DETAILED DESCRIPTION

[0070] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without innovation are within the scope of protection of the present invention.

[0071] The present invention provides a system for judging the end point of slag discharge in a pyrometallurgical furnace, which is used to quantify the amount of copper carried out and judge the end point of slag discharge in furnaces such as Teniente converter, PS converter, flash furnace and electric furnace, also known as slag discharge or slag discharge. At the appropriate time to stop slag discharge, matte copper or white matte copper reaches the limit value allowed to exist. If slag discharge is not stopped, it will be carried out together with the slag, causing copper loss.

[0072] The principle of determining the deslagging endpoint is based on the analysis of a series of deslagging images, where the different phases are identified by spectral contrast integrated into the vision system. Image acquisition is performed by a vision system consisting of a camera and a tuned narrow-band filter, which has an optical field of view of the live deslagging process.

[0073] The system captures the necessary spectral information in a non-invasive and remote manner, providing real-time information on operating conditions that can be used to make process decisions.

[0074] To better understand the present invention, please refer to Figure 1 , Figures 9 to 11 , indicating the measurement environment elements: i slag chute; ii smelting furnace or converter; iii slag observation point; iv unwanted phases brought out during slag discharge; v desired phases released; vi slag receiving tank; vii slag field of view; viiii measurement system. Specifically, the measurement system used to quantify the amount of copper brought out and determine the end point of the slag discharge process. viii includes at least the following components:

[0075] a. A multi-spectral vision system 1, comprising a camera and a tuned narrow-band filter, wherein the tuned narrow-band filter is connected to the camera, which is connected to a computer 2, and the collected image is transmitted to the computer 2 via a USB or similar communication method;

[0076] b. A computer 2 for storage, processing and control, the visual system 1 and the peripheral device 7 are connected to the computer 2;

[0077] c. an outer cover 3 isolating the internal components from external harsh conditions, particulate matter, high temperature and vibration, the visual system 1, the computer 2, the cooling system 4, the power supply 5 and the peripheral equipment 7 are all arranged on the outer cover 3, and the image acquisition end of the visual system 1 is located outside the outer cover 3;

[0078] d. An internal temperature control cooling system 4, which needs to operate at a high temperature environment temperature greater than 40°C, for heat dissipation of internal components of the system;

[0079] e. A power supply 5, including a voltage regulator, a battery and a charging module, the visual system 1, the computer 2 and the cooling system 4 are all connected to the power supply 5, and the power supply 5 supplies power to the visual system 1, the computer 2 and the cooling system 4;

[0080] f. A ground physical support structure 6 or a support arm for a vertical surface such as a wall, the support structure 6 being disposed outside the housing 3;

[0081] g. Human-computer interface, including peripheral devices 7, such as display, mouse, keyboard and wireless network card, etc.

[0082] The vision system 1 consists of three cameras, one of which uses visible near infrared VISNIR technology as a reference and is connected to a lens according to the distance between the camera and the slag outlet, for example, a 100 mm focal length lens, a working distance of 20 meters, and a field of view of 40 cm × 50 cm. The second camera uses VISNIR technology for highlighting contrasts, and is connected to a lens according to the distance between the camera and the slag outlet, and is also connected to a narrow band filter tuned to a wavelength of 1000 nm. The third camera uses short wave infrared SWIR technology for highlighting contrasts. Regarding the three cameras, the lenses have zoom, which can magnify and produce detailed and clear images at a safe distance.

[0083] The vision system 1 digitally integrates the filtered electromagnetic spectrum emitted by the outgoing melt and transmits it to the computer 2 for processing, while the housing 3 protects the internal components from the harsh environmental particulate matter, high temperature and vibration. On the other hand, the cooling system 4 maintains the temperature within the operating requirements of the equipment; the power supply 5 supplies power to the vision system 1, the computer 2 and the cooling system 4; the support structure 6 supports the housing 3 of the measurement system; the peripheral equipment 7 allows manual operation of the analysis software of the system. The vision system 1 requires a VISNIR camera with a lens and a narrow band filter tuned to 1000nm to distinguish the following stages of the slag discharge process: white matte-slag converter, matte / white matte-slag electric furnace, matte-slag smelting furnace. The vision system 1 requires a SWIR camera with a lens and a narrow band filter tuned to 1560nm to distinguish the following stages of the slag discharge process: blister copper-matte PS converter and smelting furnace.

[0084] The above-mentioned peripheral device 7 is arranged outside the outer cover 3, and analysis software is arranged on the operation interface of the peripheral device 7; the analysis software is used to quantify the proportion of each phase in the system field of view, and determine the appropriate time to stop slag discharge by analyzing the change of the copper stripping amount according to the user-defined threshold value, and generate an audio-visual alarm through the display and audio interface of the computer 2 to indicate the cessation of the slag discharge operation. In addition, the digital signal indicating the end point of the slag discharge operation is transmitted to the control room via wired or wireless communication.

[0085] The analysis software includes an image acquisition module, a region of interest selection module, a pixel calculation module, and a visualization module;

[0086] 1. Image acquisition module: used to digitize scene signals to generate useful data that can be processed;

[0087] Second, the region of interest selection module: used to obtain useful information from the acquired scene and identify the regions corresponding to the different objects under study;

[0088] 3. Pixel calculation module: used to estimate the area of ​​each phase in the slag discharge process in real time and generate its percentage indication;

[0089] 4. Visualization Module: Allows operators to visualize the slag discharge process on the hardware interface screen, obtain real-time information about the copper outflow with the slag, view historical copper loss records, and configure parameters such as image acquisition rate, allowed copper loss threshold, and activate and stop slag discharge alarms.

[0090] When the above-mentioned measuring system viii is in use, it is pointed at the slag chute of the furnace or converter at a distance of 5-30m to adjust the slag discharge field of view and produce an image of the material flowing through or out of the slag discharge chute, and each camera is connected to a focal length lens according to the distance between the camera and the slag discharge operation, adjusts the field of view of the slag discharge process, and enlarges and produces a detailed and clear image within a safe distance.

[0091] The process of determining the copper loss iv by means of the measuring system viii and of determining the end point of the deslagging operation comprises at least the following stages:

[0092] a. Arrange the measuring system viii at the slag discharge observation point iii: the measuring system device must be fixed to the ground or support structure 6, usually pointing to the slag discharge chute i of the furnace or converter at a distance of 5-30m to adjust the slag discharge field of view vii, and generate images of the material flowing through or out of the slag discharge chute, which are transmitted to the computer 2 via USB or similar communication methods;

[0093] b. Connection of measurement system components viii: The filter must be connected to the camera lens, the visual system 1 camera and peripherals 7 keyboard, monitor, mouse and wireless network card must be connected to the computer 2 that stores, processes and controls information, in addition, the visual system, computer and cooling system must be connected to the power supply 5;

[0094] c. Image capture: Using the analysis software, spectral images must be captured, using silicon-based and indium gallium arsenide (InGaAs)-based sensors for VISNIR and SWIR band capture, respectively. Image capture is performed periodically, every certain number of seconds, determined by the user.

[0095] d. Processing, calculating copper loss and determining the appropriate time to stop slag discharge: using analytical software to quantify the proportion of each phase in the field of view of the measurement system, and determining the appropriate time to stop slag discharge by analyzing the change in copper carry-out according to user-defined thresholds;

[0096] e. Generate a stop indication: the analysis software generates an audiovisual alarm through the display and audio interface of the computer 2, indicating the stop of the slag discharge operation; in addition, a digital signal indicating the end point of the slag discharge operation is transmitted to the control room via wired or wireless communication;

[0097] f. Stop slag discharge operation: The slag discharge operation must be stopped according to the generated instructions; at this time, the copper loss in the slag discharge process will not exceed the user-defined threshold.

[0098] This measuring system for determining copper losses and determining the end point of the deslagging process offers the following advantages:

[0099] Improve the copper content of slag by determining the percentage of one phase in other species

[0100] Loss control;

[0101] Increased copper recovery rate;

[0102] Reduce tank cleaning time, thereby reducing maintenance costs;

[0103] Minimize manual sampling at the slag outlet to improve worker safety;

[0104] Reduce the time operators are exposed to smelting gases.

[0105] Example

[0106] Identify the spectral bands with the greatest contrast between phases with different copper concentrations.

[0107] Laboratory tests were performed to determine the spectral bands where the contrast between white matte-slag and blister copper-matte was maximized. To this end, the vision system 1 camera of the proposed measurement system viii and various narrow-band filters were used at different VISNIR and SWIR wavelengths.

[0108] The test setup is as follows Figure 2As shown. The band selection test was conducted in a vertical electric furnace 8 capable of reaching 1500°C, the furnace body was insulated by alumina and corundum refractory bricks, the quartz reaction tube 9 was 3 inches in diameter and 3 mm thick, the stainless steel cover had an upper gas handling inlet 10 and a lower gas handling inlet 11, the upper inlet 12, the lower inlet 13 and the upper outlet 14 and the lower outlet 15 for refrigerant circulation, the window 16 had high transmittance between 350 and 5500 nanometers, and was a sky blue window as an optical channel into the reaction chamber, the thermocouple inlet in the reaction tube 17 was connected to a temperature indicator 18 and another thermocouple 19 near a silicon carbide resistor 20 connected to a PID controller 21. A constant flow of nitrogen 22 was introduced into the tubular reaction chamber through a quartz tube 23 to ensure sample stability and prevent oxidation of the sample 24. The visual system 1 consists of filters and three cameras, one camera using the VIS-NIR spectral range as a reference, the second using VIS-NIR technology with a tuned filter for contrast, and the third using SWIR with a tuned filter. The system is placed above the optical access port of the vertical electric furnace 8 at room temperature 25°C, with the lens placed vertically and forty centimeters from the sky blue window 16. The position of the visual system on the optical access port of the vertical electric furnace 8 is determined by a mechanical translator 26. The three cameras use 50 mm lenses, providing an ideal field of view, focused on the inside of the vertical electric furnace 8. The processed sample 24 corresponds to 13 products coexisting in the TC furnace, matte with a copper grade of 75%, mainly composed of copper sulfides Cu2S and iron sulfides FeS, a product coexisting with slag mainly formed by olivine slag 2FeO·SiO2 and magnetite from the PS converter, blister copper with a copper grade of more than 98.5%, and "mazamorra", a mixture of iron oxide mechanically entrained with a small amount of copper in a magnetite structure. These samples were placed in recrystallized alumina crucibles, which were then placed in a larger crucible 25.

[0109] To measure both the slag-matte and blister-matte combinations, the vertical electric furnace temperature was raised to 1300°C to melt all materials and a 100-frame video was produced for each narrow-band tuned filter.

[0110] The images of the two melts were processed to determine the contrast of the recorded intensities between each phase. To this end, the contrast between phase 1 and phase 2 for each wavelength λ was quantified using the “Michelson contrast method” according to the equation CM(λ) = |I1(λ)-I2(λ)| / (I1(λ)+I2(λ)), where I1(λ) represents the image intensity and I1(λ) and I2(λ) are calculated as the average intensity of a circular area within the crucible for each phase, respectively.

[0111] Figures 3 to 5Represents the contrast between the white matte and slag phases as a function of the spectral band and the central wavelength for each narrowband tuned filter. It can be seen that for this object phase the reference VISNIR camera achieves a contrast value of 7.7 without optical filters. Furthermore, the maximum contrast value achieved with the image is 9.6, corresponding to a VISNIR camera with a 1000nm narrowband tuned filter. The maximum contrast value is 24.6% higher than the reference value. In comparison, the human spectral sensitivity is in the range of 400-700nm, within which the highest contrast is achieved at 700nm with a contrast value of 6, so the maximum contrast achieved with the VISNIR camera with the tuned filters is also 60% higher than the highest contrast achieved within the human spectral sensitivity range.

[0112] Figures 6 to 8 Figure 1 shows the contrast between blister copper and matte phases as a function of the spectral band and the central wavelength of each narrowband tuning filter. It can be seen that for this object phase the reference VISNIR camera achieves a contrast value of 26.1 without optical filters. Furthermore, the maximum contrast value achieved with the image is 38.8, which corresponds to a SWIR camera with a 1560nm narrowband tuning filter. The maximum contrast value is 48.6% higher than the reference value. In comparison, the spectral sensitivity of humans is in the range of 400-700nm, within which the highest contrast is achieved at 700nm with a contrast value of 18.0, so the maximum contrast achieved with the SWIR camera with the tuning filter is also 115% higher than the highest contrast achieved within the human spectral sensitivity range.

[0113] The standard parts used in the present invention can all be purchased from the market, and special-shaped parts can be customized according to the description in the specification and the drawings. The specific connection methods of each part adopt conventional means such as mature bolts, rivets, welding, etc. in the prior art. Machinery, parts and equipment all adopt existing technologies and conventional models, which will not be described in detail here. The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field. Although the embodiments of the present invention have been shown and described, it can be understood by ordinary technicians in this field that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles of the present invention. The scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A system for judging the end point of slag discharge in a pyrometallurgical furnace, comprising an outer cover (3), characterized in that: The device also comprises a visual system (1), a computer (2), a cooling system (4), a power supply (5), a supporting structure (6) and a peripheral device (7); the visual system (1), the computer (2), the cooling system (4), the power supply (5) and the peripheral device (7) are all arranged on the outer cover (3); the visual system (1) and the peripheral device (7) are connected to the computer (2); the visual system (1), the computer (2) and the cooling system (4) are all connected to the power supply (5); the supporting structure (6) is arranged outside the outer cover (3); and the supporting structure (6) is used to support the outer cover (3); The visual system (1) comprises a camera and a tuned narrowband filter, the tuned narrowband filter is connected to the camera, the camera is connected to a computer (2), an image acquisition end of the visual system (1) is located outside the outer cover (3), and the visual system (1) is used to digitally integrate the filtered electromagnetic spectrum emitted by the melt out of the furnace and transmit it to the computer (2) for processing; The cooling system (4) operates in a high temperature environment and is used to dissipate heat from components inside the system so that the temperature of the components inside the system remains within an operating range; The power supply (5) comprises a voltage regulator, a battery and a charging module, and the power supply (5) is used to supply power to the visual system (1), the computer (2) and the cooling system (4); The peripheral device (7) is arranged outside the outer cover (3), and the operation interface of the peripheral device (7) is provided with analysis software; the analysis software is used to quantify the proportion of each phase in the system field of view, determine the appropriate time to stop slag discharge by analyzing the change of the copper stripping amount according to the threshold value defined by the user, and generate an audio-visual alarm through the display and audio interface of the computer (2) to indicate the cessation of the slag discharge operation, and in addition, the digital signal indicating the end point of the slag discharge operation is transmitted to the control room via wired or wireless communication; The analysis software includes an image acquisition module, a region of interest selection module, a pixel calculation module and a visualization module; 1. Image acquisition module: used to digitize scene signals to generate useful data that can be processed; Second, the region of interest selection module: used to obtain useful information from the acquired scene and identify the regions corresponding to the different objects under study; 3. Pixel calculation module: used to estimate the area of ​​each phase in the slag discharge process in real time and generate its percentage indication; 4. Visualization Module: Allows operators to visualize the slag removal process on the hardware interface screen, obtain real-time information about copper loss, view information on historical copper loss, and configure image acquisition rate, allowed copper loss threshold, and activate and stop slag removal alarm parameters.

2. A system for judging the slag discharge endpoint of a pyrometallurgical furnace according to claim 1, characterized in that: The visual system (1) comprises three cameras: a) A reference camera using VISNIR technology; b) a contrast-enhancing camera using VISNIR technology and equipped with a narrowband filter tuned to 1000 nm for distinguishing the phases of tapped white matte-slag, matte / white matte-slag in the electric furnace and matte-slag in the flash smelting furnace; c) A contrast-enhancing camera using short-wave infrared (SWIR) technology with a narrow-band filter at 1560 nm for phase differentiation in the blister copper-matte discharge from the PS converter and the flash smelting furnace.

3. A system for judging the slag end point of a pyrometallurgical furnace according to claim 2, characterized in that: Each camera is connected to a focal length lens according to the distance between the camera and the slag removal operation, adjusting the field of view of the slag removal process, zooming in and generating detailed and clear images within a safe distance.

4. A system for judging the slag discharge endpoint of a pyrometallurgical furnace according to claim 1, characterized in that: The cooling system (4) operates at a temperature above 40°C.

5. The system for judging the slag end point of a pyrometallurgical furnace according to claim 1, characterized in that: When in use, the measurement and slag discharge endpoint judgment system is pointed at the slag discharge chute of the furnace or converter at a distance of 5-30m to adjust the slag discharge field of view and generate an image of the material flowing through or out of the slag discharge chute.

6. A system for judging the slag end point of a pyrometallurgical furnace according to claim 1, characterized in that: The analysis software uses silicon-based and indium gallium arsenide-based sensors for VISNIR and SWIR band capture, and image capture is performed periodically, every certain number of seconds, determined by the user.

7. A system for judging the slag end point of a pyrometallurgical furnace according to claim 1, characterized in that: The measurement and slagging endpoint determination system captures the necessary spectral information in a non-invasive and remote manner, providing real-time information on operating conditions that can be used for process decision making.

8. The system for judging the slag end point of a pyrometallurgical furnace according to claim 1, characterized in that: The principle of the measurement and slag discharge endpoint judgment system is based on analyzing a series of slag discharge images, in which the phase is identified by spectral comparison integrated by the visual system (1).

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