Method for detecting temperature field and tuyere brick loss of colored smelting furnace bottom refractory

Abstract

The application discloses a non-ferrous smelting furnace bottom refractory temperature field and tuyere brick loss detection method, comprising the following steps: collecting thermocouple temperature and infrared radiation temperature of the tuyere brick to be measured through a thermocouple and an infrared thermometer respectively, wherein the thermocouple temperature is used as the main measured temperature, and the infrared radiation temperature is used as the verification temperature; correcting the infrared radiation temperature to obtain the infrared temperature of the tuyere brick to be measured; performing redundant verification on the thermocouple temperature based on the infrared temperature to determine the optimal temperature; calculating the hot face temperature of the tuyere brick to be measured based on the optimal temperature; and calculating the residual thickness of the tuyere brick to be measured based on the temperature difference between the hot face temperature and the optimal temperature of the tuyere brick to be measured. The application can realize online and continuous monitoring of the non-ferrous smelting furnace bottom refractory temperature field and the tuyere brick loss.

Description

Technical Field

[0001] This application relates to a method for testing tuyeres bricks, and more particularly to a method for testing the temperature field of refractory materials at the bottom of non-ferrous smelting furnaces and the loss of tuyeres bricks. Background Technology

[0002] Currently, non-ferrous smelting furnaces face significant technical shortcomings in monitoring the temperature field of refractory materials at the furnace bottom and the wear of tuyeres: the industry lacks effective online detection methods, relying mainly on manual visual inspection of molten pool surface color changes or fixed blowing times for process switching. This results in the production process being greatly affected by subjective experience and operational fluctuations, making it difficult to accurately control oxidation-reduction reactions. Meanwhile, tuyeres, as key components, are subjected to extreme environments such as high temperatures, thermal shock, slag erosion, and mechanical impacts for extended periods. Their wear status cannot be monitored in real time, and can only be judged through periodic furnace shutdowns for inspection or manual observation. This is not only inefficient and prone to errors, but also poses significant safety hazards such as copper and lead leakage. Furthermore, the temperature field of refractory materials during the baking process of new furnaces cannot be accurately obtained, and moisture discharge is controlled solely by experience-based systems, further increasing the probability of uneven thermal stress damaging the furnace lining during baking. Summary of the Invention

[0003] In view of the shortcomings of the prior art, the purpose of this application is to provide a method for detecting the temperature field of the refractory material at the bottom of non-ferrous smelting furnace and the loss of the tuyeres bricks. This application aims to realize online and continuous monitoring of the temperature field of the refractory material at the bottom of non-ferrous smelting furnace and the loss of the tuyeres bricks.

[0004] To achieve the above objectives, this application provides the following technical solution:

[0005] A method for detecting the temperature field of refractory material at the bottom of a non-ferrous smelting furnace and the loss of tuyer bricks, the method comprising: acquiring the thermocouple temperature and infrared radiation temperature of the tuyer brick to be tested, wherein the thermocouple temperature is used as the primary temperature and the infrared radiation temperature is used as the calibration temperature; correcting the infrared radiation temperature to obtain the infrared temperature of the tuyer brick to be tested; performing redundancy calibration on the thermocouple temperature based on the infrared temperature to determine the optimal temperature; calculating the hot surface temperature of the tuyer brick to be tested based on the optimal temperature; and calculating the residual thickness of the tuyer brick to be tested based on the temperature difference between the hot surface temperature and the optimal temperature.

[0006] Optionally, the correction of the infrared radiation temperature includes: obtaining the emissivity of the blind cavity wall of the air outlet brick under the current operating conditions; and using the infrared radiation temperature and the emissivity of the blind cavity wall of the air outlet brick under the current operating conditions as inputs to a pre-constructed correction formula to calculate the infrared temperature of the air outlet brick under the test.

[0007] Optionally, the correction formula is expressed as follows:

[0008]

[0009] in, Indicates the infrared radiation temperature of the blind cavity wall; This indicates the infrared temperature of the air vent brick to be tested; 273 represents the emissivity of the blind cavity wall of the air outlet brick under test under the current operating conditions; 273 represents the conversion constant between Celsius temperature and Kelvin temperature.

[0010] Optionally, the redundancy verification of thermocouple temperature based on infrared temperature includes: synchronously acquiring thermocouple temperature and infrared temperature based on a sliding window; calculating the consensus degree within the sliding window; and determining the reliability of the thermocouple temperature based on the consensus degree.

[0011] Optionally, the consensus degree within the sliding window is calculated by: calculating the difference between the temperature of each thermocouple and the infrared temperature within the sliding window; calculating the statistical characteristics of the sliding window based on the difference, the statistical characteristics including the mean and standard deviation of the difference; and calculating the consensus degree of the sliding window based on the mean and standard deviation.

[0012] Optionally, the consensus degree of the sliding window calculated based on the mean and standard deviation is expressed as:

[0013]

[0014] in, Indicates the degree of consensus; This represents the coverage factor, for example, 2; This represents the mean of the differences; The standard deviation of the difference.

[0015] Optionally, the determination of the reliability of thermocouple temperature based on consensus includes: if the difference between the current thermocouple temperature and the current infrared temperature is less than the consensus, and the consensus is less than a preset consensus, then the thermocouple temperature is determined to be reliable.

[0016] Optionally, the step of calculating the hot surface temperature of the blast furnace brick to be tested based on the optimal temperature includes: obtaining the thermal conductivity and hot surface parameters of the blast furnace brick to be tested, wherein the hot surface parameters include the heat transfer power from the molten pool to the hot surface of the blast furnace brick, the distance from the thermocouple measurement point to the hot surface of the blast furnace brick, the effective heat transfer area of ​​the hot surface of the blast furnace brick, and the cold surface temperature of the blast furnace brick to be tested; and calculating the hot surface temperature of the blast furnace brick to be tested based on the thermal conductivity, hot surface parameters, and optimal temperature.

[0017] Optionally, the hot surface temperature of the air vent brick to be tested can be calculated using the following formula:

[0018]

[0019] in, The heat transfer power from the molten pool to the hot surface of the tuyeres brick; This represents the thermal conductivity value at the current temperature. The effective heat transfer area of ​​the vent brick's hot surface needs to be calculated with corrections based on its conical shape. The correction value for the conical shape is... ; This is the distance from the thermocouple measuring point to the hot surface of the air vent brick; This indicates the optimal temperature.

[0020] Optionally, the residual thickness of the air vent brick to be tested can be calculated using the following formula:

[0021]

[0022] in, The heat transfer power from the molten pool to the hot surface of the tuyeres brick; This represents the thermal conductivity value at the current temperature. The difference between the hot surface temperature of the duct brick and the temperature measured by the thermocouple is expressed in units of... ; 235 represents the effective heat transfer area of ​​the hot surface of the tuyer brick; 235 represents the initial physical distance from the bottom of the temperature measurement blind cavity to the hot surface of the tuyer brick (the surface in contact with the molten pool); 1000 represents the conversion unit coefficient.

[0023] Compared with the prior art, the beneficial effects of this application are as follows:

[0024] This application achieves online and continuous monitoring of the temperature field of the refractory material at the bottom of the non-ferrous smelting furnace and the wear of the tuyeres by real-time acquisition of thermocouple and infrared temperature data, combined with a heat conduction model to accurately calculate the hot surface temperature and residual thickness of the tuyeres bricks. This effectively overcomes the problems of traditional methods that rely on manual experience, have large errors, and low safety, thereby improving the accuracy and reliability of process control. At the same time, it avoids safety accidents such as copper and lead leakage caused by excessive wear of the tuyeres bricks, extends the service life of the refractory material, and ensures the stable and efficient operation of the smelting process. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of the smelting furnace and the arrangement of the tuyer bricks inside the smelting furnace;

[0026] Figure 2 This is a schematic flowchart of a method for detecting the temperature field of refractory material at the bottom of a non-ferrous smelting furnace and the loss of tuyeres bricks, provided in one embodiment of this application.

[0027] Figure 3 This is a schematic diagram showing the arrangement of the air vent bricks, thermocouples, and infrared thermometers on the air vent bricks.

[0028] Figure 4 This is a schematic diagram showing the changes in thermocouple temperature and infrared temperature of different vent bricks provided in this application.

[0029] The annotations in the attached figures are explained as follows:

[0030] 1. Base brick; 2. Outer brick; 3. Brick core; 4. Thermocouple; 5. Infrared thermometer. Detailed Implementation

[0031] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0032] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in the embodiments of this application are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0033] In this application, unless otherwise expressly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0034] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0035] Figure 1 This is a schematic diagram of the smelting furnace and the arrangement of its internal tuyeres bricks. Figure 1Inside the furnace structure shown, multiple tuyer bricks are evenly arranged along the axial direction of the smelting furnace, and two tuyer bricks are usually symmetrically arranged on the radial section of the furnace body, thus forming two independent groups of permeable elements in the axial direction. Through this structural design, the redox medium can be blown into the molten pool in the furnace in a specific manner, so as to achieve directional stirring and atmosphere control of the reaction process in the molten pool, and ensure that the metallurgical reaction has good uniformity and process coverage in both the axial and radial directions. However, in the current production process of non-ferrous metallurgical smelting furnaces, there are certain technical shortcomings in the monitoring of the thickness and condition of the tuyeres bricks at the bottom of the furnace. On the one hand, due to the lack of effective online detection of the gas-liquid phase temperature near the tuyeres bricks at the bottom of the molten pool, process switching has long relied on manual visual inspection of the molten pool color or fixed time settings, resulting in insufficient control precision of the oxidation-reduction reaction and large process deviations. On the other hand, as a key component, the tuyeres bricks are subjected to complex loads such as severe alternating temperature changes, mechanical impacts, slag erosion, and oxygen-rich scouring over a long period of time, making them prone to thermal shock damage, high-temperature creep, spalling, and even breakage. However, there is a lack of reliable loss detection methods, which means that equipment condition assessment still relies on intermittent, experience-based furnace shutdown inspections. This not only fails to grasp the changes in refractory residual thickness in real time, but also creates serious safety hazards such as copper and lead leakage, severely restricting the continuity, stability, and safety of production.

[0036] To address the above problems, this application provides a method for detecting the temperature field of the refractory material at the bottom of a non-ferrous smelting furnace and the loss of tuyeres bricks, such as... Figure 2 As shown, the method includes the following steps:

[0037] S100: Collects the temperature of the tuyer brick to be tested inside the smelting furnace. This temperature includes thermocouple temperature and infrared radiation temperature.

[0038] Before implementing this step, it is necessary to first conduct performance tests on the standard duct bricks to obtain the corresponding data table of temperature-physical property parameters of the duct bricks, as shown in Table 1:

[0039] Table 1

[0040]

[0041] This application tested the thermal conductivity and specific heat capacity of standard tuyere bricks with the above basic parameters at different temperature points, and obtained the temperature-physical property data table of the standard tuyere bricks as shown in Table 2:

[0042] Table 2

[0043]

[0044] Based on the linear decreasing trend of thermal conductivity with increasing temperature (note: approximately 0.3 W / (m·K) for every 100℃ increase), the thermal conductivity at 1200℃ is 2.6±0.3 W / (m·K), and linearly extrapolated to approximately 2.5±0.3 W / (m·K) at 1230℃. The following calculations use 2.5 W / (m·K) to calculate the heat transfer power at 1230℃ with a hot surface diameter of 210 mm, ranging from 339 W to 486 W. We then take the empirical value of 368 W.

[0045] In this step, such as Figure 3 As shown, the tuyer brick includes a base brick 1, a sleeve brick 2, and a brick core 3. The base brick 1 is installed at the oxidation-reduction tuyer inside the furnace body, and a through groove is provided in its center. The brick core 3 passes through the oxidation-reduction tuyer and the through groove. The sleeve brick 2 is fitted around the outer periphery of the brick core 3 and is located in the through groove. In order to implement temperature monitoring, this application drills two axial blind cavities with a depth of about 220 mm to 235 mm along the cold side to the hot side of each tuyer brick (for example, measuring 10 tuyer bricks). A redundant temperature measurement system consisting of a thermocouple and an infrared thermometer is embedded in the two blind cavities respectively. The thermocouple is used to directly measure the internal temperature of the brick core 3 and uses it as the main measurement temperature. The infrared thermometer is used to measure the infrared radiation temperature of the wall of the blind cavity and uses it as the calibration temperature.

[0046] For example, in a specific process stage (such as the mid-oxidation stage of the tuyer brick), this application uses thermocouples and infrared thermometers installed in the blind cavity to collect the thermocouple temperature of the tuyer brick under test and the infrared radiation temperature of the blind cavity wall in real time, as shown in Table 3:

[0047] Table 3

[0048]

[0049] It should be noted that the infrared thermometer measures the infrared radiation temperature of the wall surface of the blind cavity of the air vent brick under test, not the actual physical temperature of the air vent brick. According to the Stefan-Boltzmann law, the radiant power of the blind cavity wall is proportional to the fourth power of its surface temperature, that is:

[0050]

[0051] in, This represents the radiated power per unit area of ​​the blind cavity wall. Indicates the emissivity of the blind cavity wall; This represents the Stefan-Boltzmann constant; This represents the absolute temperature of the wall of the blind cavity, expressed in Kelvin (K).

[0052] S200: Corrects the infrared radiation temperature to obtain the infrared temperature of the air vent brick to be tested;

[0053] In this application, the infrared thermometer measures the infrared radiation temperature of the blind cavity wall. This temperature assumes the brick at the air vent being tested is a blackbody (emissivity). However, in reality, the emissivity of the blind cavity wall is less than 1. Therefore, it is necessary to obtain the emissivity of the blind cavity wall of the air outlet brick under the specific process stage described above. This emissivity can be obtained through the following process:

[0054] Under the same laboratory conditions as the specific process stage mentioned above, the inner wall of the blind cavity was polished with 200-grit abrasive to control the surface roughness within the range of 5μm to 15μm, so as to eliminate the influence of surface condition differences on emissivity. Subsequently, using a blackbody radiation source or a standard infrared thermometry calibration device, the radiation temperature and the actual temperature of the blind cavity wall were compared and measured at a specific infrared wavelength (2μm to 3μm). The emissivity value of the blind cavity wall under this specific process stage was calculated to be 0.74 to 0.75.

[0055] Furthermore, based on the emissivity at this specific process stage, the infrared radiation temperature of the blind cavity wall is corrected to the infrared temperature of the air outlet brick under test. The corrected formula is expressed as follows:

[0056]

[0057] in, Indicates the infrared radiation temperature of the blind cavity wall; This indicates the infrared temperature of the air vent brick to be tested; The emissivity of the blind cavity wall of the air outlet brick under test is given under the current operating conditions. For example, it can be taken as 0.74 to 0.75 (single-wave infrared, wavelength 2μm to 3μm); 273 represents the conversion constant between Celsius temperature (°C) and Kelvin temperature (K).

[0058] After correcting the infrared radiation temperatures shown in Table 3 based on the above formula, the infrared temperatures of the air vent bricks to be tested can be obtained as shown in Table 4:

[0059] Table 4

[0060]

[0061] As shown in Table 4, the corrected infrared temperature and thermocouple temperature of the tested air vent brick are on the same order of magnitude, making them comparable and thus reliable data sources for input into subsequent models to calculate the residual thickness of the air vent brick. It should be noted that if the infrared radiation temperature of the blind cavity wall is not corrected, the measured temperature of the blind cavity will be significantly lower than expected, leading to severe distortion of the hot surface temperature calculated using the heat conduction formula, ultimately making it impossible to accurately estimate the residual thickness of the tested air vent brick.

[0062] also, Figure 4 Table 4 shows the thermocouple and infrared temperature variation curves for different vent bricks. Figure 4 It can be seen that the two have the same overall trend and the same magnitude, but there are significant differences at individual points (such as wind tunnel brick 3), which verifies the necessity of subsequent redundant verification.

[0063] In summary, after the infrared thermometer receives the infrared energy radiated from the wall of the blind cavity and outputs the apparent temperature, it is physically corrected by introducing the emissivity of the material surface. The correction formula is then used to convert it into the true physical temperature, thereby eliminating the measurement deviation caused by the non-blackbody radiation characteristics and ensuring the accuracy and reliability of the temperature at the blind cavity. This provides effective input for subsequent temperature field modeling and loss analysis.

[0064] S300: Redundancy verification of thermocouple temperature based on infrared temperature, specifically including the following steps:

[0065] S301: Synchronous acquisition of thermocouple temperature and infrared temperature based on sliding window;

[0066] In this step, this embodiment maintains a fixed-length, first-in-first-out (FIFO) data buffer of length N (e.g., N=5) as a sliding window. Thermocouple temperatures are synchronously acquired during each sampling period. and corrected infrared temperature And form a new data pair ( , The data is then pushed into the window. When the amount of data in the window exceeds the length N, older data will be automatically removed, thus ensuring that the window always retains the synchronous measurement data of the most recent N periods, providing the latest data for subsequent consensus analysis.

[0067] S302: Calculate the consensus level within the sliding window;

[0068] In this step, the first step is to calculate the difference between the temperature of each thermocouple and the infrared temperature within the sliding window:

[0069]

[0070] Subsequently, the statistical characteristics of the entire sliding window, namely the mean of the differences, are calculated based on the differences in each set of data. and standard deviation This leads to a consensus:

[0071]

[0072] in, Indicates the degree of consensus; This represents the coverage factor, for example, 2.

[0073] S303: Determine the reliability of thermocouple temperature based on consensus.

[0074] In this step, the thermocouple temperature at the current moment is first calculated. and current infrared temperature The difference Then, the difference and consensus and the pre-set consensus level (For example, at 30℃) The following comparisons are made:

[0075] like and If the thermocouple temperature is found to be reliable, then the optimal temperature can be obtained by weighted average calculation.

[0076]

[0077] in, Indicates the preset weight; Indicates the optimal temperature; This indicates the current thermocouple temperature; This indicates the current infrared temperature.

[0078] If the above conditions are not met, the thermocouple temperature is determined to be unreliable. In this case, an infrared temperature alarm can be triggered, and the infrared temperature will be used as the optimal temperature.

[0079] In summary, the consensus-based redundancy verification method proposed in this application verifies the system stability by comparing the macroscopic characterization (consensus degree C) with the microscopic deviations of the current thermocouple temperature and infrared temperature. By combining these technologies, the system can complete its self-assessment of credibility without the need for a precise physical model, relying solely on the inherent consistency of the data. This reduces computational complexity while giving the system dual robustness against slow drift and transient anomalies, as well as the ability to make adaptive decisions in response to different operating conditions.

[0080] S400: Calculate the hot surface temperature of the tuyer brick to be tested based on the optimal temperature, that is, the temperature of the contact surface between the tuyer brick to be tested and the molten pool.

[0081] First, based on the estimated temperature at the current stage of the process, select the corresponding thermal conductivity from Table 2 ( ) and specific heat capacity.

[0082] Secondly, since thermocouple temperature is generally more direct and reliable, this application prioritizes using thermocouple temperature as the input value for calculating the optimal temperature of the hot surface of the vent brick, while infrared temperature can be used for verification and backup. For example, if the thermocouple is broken, drifted, or damaged, its reading will be abnormal. In this case, the system can automatically detect this abnormality and trigger an alarm, while simultaneously switching to using infrared temperature measurement values ​​for calculation, ensuring that the entire detection process is uninterrupted.

[0083] Specifically, the hot surface temperature of the vent brick to be tested can be calculated using the temperature field model shown below:

[0084]

[0085]

[0086]

[0087] in, This is the heat transfer power from the molten pool to the hot surface of the tuyer brick, for example, 368W; This represents the thermal conductivity value at the current temperature. The value represents the difference between the hot and cold surfaces of the air vent brick being tested, expressed in units of... ; The effective heat transfer area of ​​the hot surface of the air vent brick to be tested needs to be corrected according to its conical shape. The correction value for the conical shape is... ; This is the distance from the thermocouple measuring point to the hot surface of the vent brick, for example, 0.235m.

[0088] It should be noted that thermal conductivity The value is determined according to different process stages, as shown in Table 5:

[0089] Table 5

[0090]

[0091] The hot surface temperatures of the air vent bricks calculated using the formula above are shown in Table 6.

[0092] Table 6

[0093]

[0094] S500: Calculate the residual thickness of the air outlet brick to be tested based on the temperature difference between the hot surface temperature and the optimal temperature.

[0095] In this step, the loss of the vent brick (reduction in thickness) will cause a change in thermal resistance, which will affect the temperature at the measuring point. By inferring the thermal resistance using a known heat transfer model, the current thickness of the vent brick can be calculated.

[0096] This application utilizes the calculated hot surface temperature The difference between the temperature of the thermocouple and the optimal temperature And based on the formula shown below, the residual thickness of the duct brick to be tested at the current process stage is calculated:

[0097]

[0098] Where 235 represents the initial physical distance from the bottom of the temperature measurement blind cavity to the hot surface of the tuyeres brick (the surface in contact with the molten pool); 1000 represents the conversion unit coefficient.

[0099] Given the standard thickness of the tuyeres brick, the residual thickness of the tuyeres brick at a specific process stage (such as the middle stage of oxidation) is calculated based on the above formula, as shown in Table 7:

[0100] Table 7

[0101]

[0102] To verify the accuracy of the residual thickness data of the wind tunnel bricks calculated based on the scheme described in this application, this application constructs a multi-level, mutually corroborating comprehensive verification system, specifically including the following three methods:

[0103] 1. Pre-production benchmark verification: Before product production, standard vent brick samples with specific compositions and physical properties are sent to a nationally accredited engineering center for laboratory calibration. This process simulates high-temperature conditions and accurately measures the thermophysical parameters of the material (such as thermal conductivity and specific heat capacity), thereby establishing an accurate and reliable initial data benchmark for the calculation model and ensuring the scientific validity of the theoretical model.

[0104] 2. Periodic Verification During Production: During idle periods or maintenance, high-precision 3D laser scanning technology is used to perform non-contact measurements on the inner wall of the furnace lining. This allows for the acquisition of macroscopic morphology and consumption data for the entire furnace lining area, including the tuyere bricks. This provides an intuitive and comprehensive spatial comparison and verification of the residual thickness data provided by the calculation model, effectively assessing the overall wear status of the furnace lining.

[0105] 3. Final Verification After Offline: When the vent bricks reach the end of their service life and need to be replaced, the actual residual thickness of the bricks is precisely measured. This measured data is then precisely compared with the final set of residual thickness data calculated by the system before offline replacement. This closed-loop verification is the most direct and authoritative evidence to verify the accuracy of the calculation method and provides valuable feedback data for continuous optimization of the model algorithm.

[0106] Through the above-mentioned full lifecycle verification process of "benchmark establishment before production - cycle comparison during production - final verification after offline", the reliability of the residual thickness data obtained in this application is fully demonstrated, providing solid data support for safety early warning and precise maintenance in industrial applications.

[0107] Furthermore, to verify the accuracy and reliability of the temperature field model and the method for calculating the residual thickness of the tuyeres bricks proposed in this application, this application actually measured the temperature of the molten pool surface surging point at the furnace inspection hole using a Fluke Raytek 3iPlus handheld infrared thermometer, obtaining the actual process temperatures shown in Table 8:

[0108] Table 8

[0109]

[0110] Calculations show that, as shown in Table 8, the average error between the furnace outside temperature and the tuyer brick hot surface temperature calculated based on the aforementioned temperature field model is ≤0.25%. This extremely low error rate fully verifies the high accuracy and reliability of the temperature field model established in this application. It should be noted that, although in practical applications, differences in process conditions, furnace volume, design materials, and tuyer arrangement may have some impact on the absolute value of a single measurement, the core of this application lies in establishing a universal dynamic monitoring system. By following the device configuration and data acquisition and analysis methods provided in this application, and optimizing parameters through initial calibration, continuous dynamic monitoring of the refractory temperature field at the bottom of the molten pool and the residual thickness of the tuyer brick can be accurately achieved, effectively overcoming the influence of individual differences.

[0111] It should be noted that, firstly, the measured data used in this application are from on-site collection from two 480t anode furnaces. Although there are differences in process conditions, furnace volume, design materials, and tuyeres arrangement between different furnaces, which may affect some individual measured values, the device configuration and data processing method provided in this application, combined with initial parameter calibration and dynamic optimization, can still effectively achieve continuous and dynamic monitoring of the refractory temperature field at the bottom of the molten pool and the residual thickness of the tuyeres bricks. Secondly, the core of this application lies in introducing thermal conductivity as a key parameter to characterize the heat conduction behavior of the tuyeres bricks along the airflow direction (blown into the molten pool from the bottom of the furnace). The tuyeres bricks involved are a specific type of refractory material, with its core mainly composed of 55% MgO, 20% Cr2O3, and 2% FeCO3, fired at high temperatures, and possessing the following properties: compressive strength ≥30 MPa, reheat linear shrinkage ±0.1% (1500℃, 3h), and bulk density ≥3.25 g / cm³. 3The thermal shock resistance (water cooling at 1000℃) is ≥20 cycles, the apparent porosity is ≤14.5%, the linear expansion rate is 0.7% (1000℃), and the load softening temperature is ≥1650℃. Furthermore, to ensure the accuracy of infrared temperature measurement, the inner wall of the blind cavity where the infrared temperature measuring device is located is polished with 200-mesh abrasive, with the roughness controlled between 5μm and 15μm to eliminate the interference of different sample surface conditions on the emissivity calibration results. Finally, the redundant configuration of thermocouples and infrared temperature measuring elements used in this application has the following two advantages: First, it fully utilizes the complementary characteristics of the two types of elements, enabling it to adapt to changes in working conditions such as shrinkage of masonry materials, brick melting or fracture, and timely triggering of alarms; second, through mutual comparison and verification of the two temperature measurement data, it improves the reliability of temperature field reconstruction and calculation of the residual thickness of the tuyeres bricks, providing solid data support for metallurgical process analysis and optimization.

[0112] This application establishes a redundant temperature measurement system consisting of thermocouples and infrared thermometers inside each tuyer brick in a non-ferrous smelting furnace. By collecting the internal temperature of the tuyer brick in real time and combining it with pre-calibrated refractory thermal conductivity parameters, a temperature field calculation model is established to dynamically calculate the refractory temperature distribution at the bottom of the molten pool and the real-time residual thickness curve of the tuyer brick. This enables online monitoring of the critical oxidation-reduction process temperature and accurate assessment of the tuyer brick wear status, effectively solving the process control deviations and safety risks caused by traditional reliance on manual experience judgment, and thus helping to improve production continuity and process stability.

[0113] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A method for detecting the temperature field of refractory material at the bottom of a non-ferrous smelting furnace and the loss of tuyeres bricks, characterized in that, The method includes: The thermocouple temperature and infrared radiation temperature of the air vent brick to be tested were collected respectively, with the thermocouple temperature as the main measured temperature and the infrared radiation temperature as the calibration temperature. The infrared radiation temperature is corrected to obtain the infrared temperature of the air vent brick to be tested; Redundancy verification of thermocouple temperatures based on infrared temperature is performed to determine the optimal temperature. This redundancy verification includes: Thermocouple temperature and infrared temperature are simultaneously acquired using a sliding window. Calculating the consensus level within the sliding window includes: Calculate the difference between the temperature of each thermocouple and the infrared temperature within the sliding window; The statistical characteristics of the sliding window are calculated based on the difference, including the mean and standard deviation of the difference. The consensus level of the sliding window is calculated based on the mean and standard deviation, and is expressed as: in, Indicates the degree of consensus; This represents the coverage factor, which is 2. This represents the mean of the differences; The standard deviation of the difference; The reliability of thermocouple temperature is determined based on consensus, including: If the difference between the current thermocouple temperature and the current infrared temperature is less than the consensus level, and the consensus level is less than the preset consensus level, then the thermocouple temperature is determined to be reliable. The hot surface temperature of the air vent brick to be tested is calculated based on the optimal temperature. The residual thickness of the air vent brick is calculated based on the temperature difference between the hot surface temperature and the optimal temperature.

2. The method according to claim 1, characterized in that, The correction of the infrared radiation temperature includes: Obtain the emissivity of the blind cavity wall of the air outlet brick under the current operating conditions; The infrared temperature of the air outlet brick under test is calculated by using the infrared radiation temperature and the emissivity of the blind cavity wall of the air outlet brick under the current operating conditions as inputs to the pre-constructed correction formula.

3. The method according to claim 2, characterized in that, The corrected formula is expressed as follows: in, Indicates the infrared radiation temperature of the blind cavity wall; This indicates the infrared temperature of the air vent brick to be tested; 273 represents the emissivity of the blind cavity wall of the air outlet brick under test under the current operating conditions; 273 represents the conversion constant between Celsius temperature and Kelvin temperature.

4. The method according to claim 1, characterized in that, The calculation of the hot surface temperature of the air vent brick based on the optimal temperature includes: The thermal conductivity and hot surface parameters of the blast furnace brick to be tested are obtained. The hot surface parameters include the heat transfer power from the molten pool to the hot surface of the blast furnace brick, the distance from the thermocouple measurement point to the hot surface of the blast furnace brick, the effective heat transfer area of ​​the hot surface of the blast furnace brick, and the cold surface temperature of the blast furnace brick to be tested. The hot surface temperature of the air vent brick to be tested is calculated based on thermal conductivity, hot surface parameters, and optimal temperature.

5. The method according to claim 4, characterized in that, The hot surface temperature of the air vent brick to be tested is calculated using the following formula: in, The heat transfer power from the molten pool to the hot surface of the tuyeres brick; This represents the thermal conductivity value at the current temperature. The effective heat transfer area of ​​the vent brick's hot surface needs to be calculated with corrections based on its conical shape. The correction value for the conical shape is... ; This is the distance from the thermocouple measuring point to the hot surface of the air vent brick; This indicates the optimal temperature.

6. The method according to claim 1, characterized in that, The residual thickness of the air vent brick to be tested is calculated using the following formula: in, The heat transfer power from the molten pool to the hot surface of the tuyeres brick; This represents the thermal conductivity value at the current temperature. This represents the difference between the hot surface temperature of the tuyer brick and its optimal temperature, expressed in units of... ; 235 represents the effective heat transfer area of ​​the hot surface of the vent brick; 235 represents the initial physical distance from the bottom of the temperature measurement blind cavity to the hot surface of the vent brick; 1000 represents the conversion unit coefficient.

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