A method for low return fines sintering

Abstract

The application discloses a low-return ore sintering method, which is characterized by the following steps: through the online monitoring feedback mode, using the section real-time data of the section red layer brightness, the section red layer chroma, the section red layer continuity, the section red layer thickness and the section red layer height in the finished ore vertical section, accurately grasping the residual carbon rate of the material layer, and according to the relationship between the residual carbon rate of the material layer and the surface layer return ore rate, innovatively optimizing and adjusting the sintering ignition process, realizing the combustion of residual carbon at low cost, low energy consumption and low carbon emission, and then significantly reducing the surface layer return ore rate and effectively improving the sintering product rate. In addition, the secondary sintering reaction of the hot finished ore due to residual carbon in the subsequent cooling process can be eliminated, the material blockage phenomenon under the circular cooler can be avoided, and the production safety can be improved.

Description

Technical Field

[0001] This invention relates to iron and steel sintering technology, specifically to a method for sintering with low return ore, and belongs to the field of sintering technology. Background Technology

[0002] In existing iron ore sintering processes, the sintering machine trolley, after being filled with the sintering mixture via a nine-roller feeder, slowly enters the furnace chamber. It first enters the ignition section, where it is heated by the high-temperature flames generated by two rows of gas burners. The coke powder in the mixture is gradually ignited, forming a red-hot combustion zone. Subsequently, it enters the heat preservation section, where it is heated by the medium-temperature flames generated by a row of heat preservation burners. The purpose of this is to maintain the temperature of the freshly sintered high-temperature sinter, preventing the formation of brittle powder due to rapid cooling. One end of the gas burner is connected to a gas pipeline. The gas used is generally industrial metallurgical by-product gas, such as blast furnace gas, converter gas, coke oven gas, blast furnace-converter mixed gas, and blast furnace-coke mixed gas, with a small portion using natural gas. The other end is connected to an air pipeline, introducing air blown in by the combustion blower, which mixes with the gas to form a combustion flame. The ignition furnace is typically installed parallel to the sintering machine trolley, usually about 100-200mm above the trolley's side rails. It consists of three beams (front beam, middle partition beam, and rear beam), two furnace tops (ignition section top and insulation section top), and four side walls (two for the ignition section and two for the insulation section), with a total length generally of 7-9 meters, of which the ignition section is 3-4 meters and the insulation section is 4-5 meters. Ignition is the core and critical step in the sintering machine process. Whether the ignition is uniform, whether the combustion zone is qualified, and whether the ignition furnace has a long enough lifespan all determine the quality indicators, energy consumption indicators, and operating rate indicators of the entire sintering process.

[0003] Currently, due to various limitations in the ignition process of sintering, a significant amount of residual carbon remains on the material surface after ignition. This residual carbon can lead to a reducing atmosphere in localized areas of the material surface, resulting in a reduction in the production of composite calcium ferrite required for normal sintering. Consequently, the amount of ore returned from the sintering material surface increases, making it difficult to further improve the overall yield of the sintering process. Summary of the Invention

[0004] To address the problem of low yield caused by excessive ore return during sintering in existing technologies, this invention provides a method for low-return ore sintering. This method involves monitoring cross-sectional data at the tail of the sintering machine, including the brightness, chroma, continuity, thickness, and height of the red layer in the vertical section of the finished ore. Based on this data, the surface ore return rate and residual carbon rate are calculated. Using this information as a basis, oxygen injection and / or secondary ignition are selectively performed downstream of the ignition furnace at the machine head. This reduces the ore return rate at low cost and effectively improves the sintering yield.

[0005] To achieve the above-mentioned technical objectives, the technical solution adopted by the present invention is as follows:

[0006] A method for sintering low-return ore, the method comprising:

[0007] 1) The trolley containing the sintering material runs from the head to the tail of the sintering machine. During this process, the sintering material is ignited by the furnace at the head of the machine and enters the sintering stage. After sintering is completed, the hot sintered finished ore is discharged from the tail of the sintering machine.

[0008] 2) Real-time monitoring of the vertical cross-section of the hot-sintered finished ore at the tail of the sintering machine yields cross-sectional data including the brightness, chroma, continuity, thickness, and height of the red layer. The surface return rate is then calculated based on this data, and finally, the surface carbon consumption and residual carbon rate are calculated sequentially using the surface return rate.

[0009] 3) Based on the residual carbon content of the material layer, oxygen injection treatment or secondary ignition treatment is carried out on the sintering material entering the sintering stage to reduce the amount of returned ore in the finished ore.

[0010] It should be noted that the continuity of the red layer in the cross-section refers to the continuity in the horizontal direction. Because the red layer (combustion zone) in the sintering material layer is a horizontal, continuous, and stably descending high-temperature zone, the continuity we refer to here means that there should be no breaks in the horizontal direction. For example, the left side of the material layer should have a faster-burning combustion zone below, while the right side should have a slower-burning combustion zone above. The continuity is defined as the percentage obtained by dividing the area of ​​the red layer that is neat and without breaks by the total area of ​​the red layer. The thickness of the red layer in the cross-section refers to the average thickness in the vertical direction. The height of the red dust in the cross-section refers to the average height from the surface of the sintering trolley.

[0011] Preferably, in step 2), the surface ore return rate is calculated based on the obtained cross-sectional data: the calculation formula for the surface ore return rate using the cross-sectional data as a variable is as follows:

[0012]

[0013] In equation (1), C 返矿 α represents the surface ore return rate, in degrees. γ represents the cross-sectional red layer brightness, in degrees. γ represents the cross-sectional red layer chromaticity, in degrees. θ represents the cross-sectional red layer continuity, in degrees. δ represents the cross-sectional red layer thickness, in mm. h represents the cross-sectional red layer height, in mm. a represents the first ore return constant, with a value of 0.8–2. b represents the second ore return constant, with a value of 0.01–1.

[0014] Preferably, in step 2), the surface carbon consumption and the residual carbon rate are calculated sequentially based on the surface return rate: the surface carbon consumption is calculated using the surface return rate as a variable, and then the residual carbon rate is calculated using the surface carbon consumption as a variable.

[0015] W 耗碳 =Q 表层 ×(1-C 返矿 )×j×c (2).

[0016]

[0017] In equations (2)-(3), W 耗碳 Surface carbon consumption, kg / m 2 C 残碳 The residual carbon content of the material layer is %. Q 表层 C represents the total amount of surface sintering material, in kg. 返矿 denoted as surface return ore rate (%), j as unit carbon consumption of sinter (kg / kg), β as solid fuel addition in sinter (kg / t), and c as carbon consumption correction factor (value from 1 to 5).

[0018] Preferably, step 3) includes:

[0019] 301) When the thickness H of the sintered material layer is less than 600 mm and the residual carbon content C of the material layer is less than 600 mm, the sintered material layer is less than 600 mm. 残碳 When <0.3% or when the sintered material layer thickness H≥600mm and the residual carbon content C of the material layer is <0.3%, 残碳 When the content is <0.5%, the sintering material entering the sintering stage is only treated with oxygen spraying.

[0020] 302) When the thickness H of the sintered material layer is less than 600 mm and the residual carbon content C of the material layer is less than 600 mm, the sintered material layer is less than 600 mm. 残碳 When ≥0.3% or when the sintered material layer thickness H≥600mm and the residual carbon content C of the material layer is... 残碳 When the content is ≥0.5%, the sintering material entering the sintering stage is subjected to secondary ignition treatment.

[0021] Preferably, in step 301), the amount of oxygen required to treat the sintering material entering the sintering stage by only injecting oxygen is calculated based on the ignition intensity of the ignition furnace and the residual carbon content of the material layer. Then:

[0022]

[0023] In equation (4), Q 氧气 m is the amount of oxygen required for oxygen injection when only oxygen injection is performed. 3 / s. β represents the amount of solid fuel added to the sinter, in kg / t. ω 点火 The ignition intensity of the furnace, in MJ / m³ 2 d is the operating constant for single oxygen injection, with a value ranging from 1 to 5.

[0024] Preferably, in step 302), the ignition time required for secondary ignition treatment of the sinter entering the sintering stage is calculated based on the ignition intensity of the ignition furnace, the residual carbon rate of the sintering layer, the thickness of the sintering layer, and the amount of solid fuel added to the sintering material. Then:

[0025]

[0026] In equation (5), t 二次 ω represents the duration of secondary ignition, in seconds. 点火 The ignition intensity of the furnace, in MJ / m³ 2 β is the amount of solid fuel added to the sinter, in kg / t. e is the second ignition duration constant, with a value ranging from 10 to 100.

[0027] Preferably, in step 302): the time interval required for the die head ignition furnace to ignite the sintering material twice is calculated based on the ignition intensity of the ignition furnace, the residual carbon rate of the material layer, the thickness of the sintering material layer, and the amount of solid fuel added to the sintering material. Then:

[0028]

[0029] In equation (6), t 间隔 The time interval between two ignitions is s. 碳氧 λ is the carbon-oxygen burnout ratio coefficient, ranging from 0.5 to 2. V is the running speed of the sinter, in m / s. λ is the oxygen intake coefficient of the sinter surface, ranging from 20 to 40. f is the ignition interval constant, ranging from 1 to 10.

[0030] Preferably, the sinter is subjected to an oxygen injection treatment after the primary ignition treatment and before the secondary ignition treatment, and / or, the sinter is subjected to a secondary oxygen injection treatment after the secondary ignition treatment. Based on the residual carbon content of the sinter bed, the amount of solid fuel added to the sinter, the duration of the primary ignition, and the duration of the secondary ignition, the required amount of oxygen injected for the primary and secondary oxygen injection treatments is calculated, resulting in:

[0031]

[0032] In equations (7)-(8), Q 一次氧 The amount of oxygen injected in one cycle, m 3 / s. t 一次 The duration of one ignition cycle is measured in seconds (s). Q 二次氧 This refers to the secondary oxygen injection volume, m 3 / s. ζ is the burnout coefficient over time, ranging from 0.1 to 1. π is the carbon-oxygen replacement coefficient, ranging from 10 to 20.

[0033] It should be noted that all formulas in this invention were obtained by the inventor based on experimental and engineering applications, and all calculations were obtained by substituting the converted values ​​into the formulas after conversion (after conversion, only the values ​​are substituted into the formulas, not the units; the units are only used to adjust the magnitude of the values).

[0034] Preferably, the method employs a sintering system with a tail section monitoring mechanism. This sintering system includes a sintering machine, a feeding machine, a primary ignition furnace, a primary oxygen injection mechanism, a secondary ignition furnace, a secondary oxygen injection mechanism, and a tail section monitoring mechanism. According to the direction of the sintering mixture, the feeding machine, primary ignition furnace, primary oxygen injection mechanism, secondary ignition furnace, and secondary oxygen injection mechanism are sequentially arranged on the fume hood of the sintering machine. The tail section monitoring mechanism is located downstream of the tail of the sintering machine.

[0035] Preferably, the tail section monitoring mechanism is an industrial camera.

[0036] Preferably, the primary and secondary ignition furnaces have identical structures, both including a furnace body and burners. The furnace body is mounted on the fume hood of the sintering machine, and a through-hole for the burners, narrow at the top and wide at the bottom, is provided at the top of the furnace body. The bottom end of the burner through-hole communicates with the inner cavity of the fume hood of the sintering machine. The upper part of the burner is connected to the top of the furnace body via a fixing plate and a telescopic rod, and the lower end of the burner extends into the burner through-hole and extends to the bottom end of the burner through-hole. The tilt angle of the burners in the vertical plane is adjusted by the fixing plate and the telescopic rod. Preferably, the furnace body is connected to the frame of the sintering machine or to the ground via a wheeled support frame. The horizontal position of the furnace body on the fume hood of the sintering machine is adjusted by the wheeled support frame in the horizontal direction of the sintering mixture's movement. Preferably, both the primary and secondary ignition furnaces have multiple angle-adjustable burners, which are evenly distributed on the furnace body.

[0037] Preferably, the primary oxygen injection mechanism and the secondary oxygen injection mechanism have the same structure, both including at least one oxygen injection pipe with an independent throttle valve.

[0038] In this invention, addressing the issue of high surface return rate in sintered ore, research has revealed a close correlation between the surface return rate and the residual carbon content of the sintering bed. Generally, a higher residual carbon content leads to a higher surface return rate, and vice versa. The two show a positive correlation. In other words, if the fuel added to the sintering material can be burned as completely as possible, reducing the residual carbon content to near zero (a residual carbon content below 0.1% is considered complete combustion), the surface return rate can be significantly reduced, thereby greatly improving the sintering yield and increasing single-unit capacity. In actual operation, due to fluctuations in the cost of sintered materials, the residual carbon rate of the sintering layer varies even in production systems with relatively constant operating conditions. Therefore, by accurately obtaining the real-time residual carbon rate of the sintering layer based on changes in actual operating conditions and taking targeted measures to remove residual carbon, it is possible to achieve low-cost and efficient removal of residual carbon without increasing energy consumption and carbon emissions, ultimately reducing the amount of returned ore. Based on this objective, this invention has discovered that by real-time monitoring of the vertical cross-section of the hot-sintered finished ore at the tail of the sintering machine, real-time cross-sectional data including the brightness, chroma, continuity, thickness, and height of the red layer can be obtained. Furthermore, the residual carbon rate of the sintering layer can be accurately calculated based on the obtained cross-sectional data. Finally, based on the calculated residual carbon rate, the current sintering process can be improved by adding oxygen injection and / or secondary ignition treatment to achieve basic removal of residual carbon, thereby reducing the amount of returned ore in the finished ore. The calculation process for the residual carbon rate of the material layer is shown in the above formulas (1)-(3).

[0039] In this invention, different methods can be used to treat the material layer according to its residual carbon content. Generally, if the residual carbon content is low, it is only necessary to inject oxygen into the sintering material surface after the first ignition treatment (i.e., a first oxygen injection treatment) to assist combustion and achieve effective combustion of the residual carbon (i.e., the entire sintering process is a sintering mode of first ignition + first oxygen injection). If the residual carbon content is high, the method of injecting oxygen to assist combustion cannot effectively achieve combustion of the residual carbon (the sintering machine has a limited length, making it impossible to perform oxygen blowing operation on the sintering material surface for a long time, and excessive oxygen injection will affect the sintering temperature field). Therefore, it is necessary to perform a second ignition on the sintering material with a high residual carbon content and to finely control the second ignition treatment to achieve efficient combustion of the residual carbon (i.e., the entire sintering process is a sintering mode of first ignition + second ignition). If necessary, oxygen injection and second ignition treatment can also be performed simultaneously.

[0040] In this invention, when the residual carbon rate of the material layer is determined to be low, the residual carbon can be burned off by adding only one oxygen injection treatment. In order to reduce the treatment cost while ensuring the treatment effect, it is necessary to strictly control the amount of oxygen injected. In this invention, the amount of oxygen required to perform only oxygen injection treatment on the sintering material entering the sintering stage is calculated by using the ignition intensity of the ignition furnace and the residual carbon rate of the material layer as independent variables. For the specific calculation formula, please refer to the above formula (4).

[0041] In this invention, when it is determined that the residual carbon rate of the sintering bed is high, a secondary ignition treatment is required to achieve the combustion of the residual carbon. In order to reduce the treatment cost while ensuring the treatment effect, the ignition time of the secondary ignition treatment needs to be strictly controlled. In this invention, the ignition time required for the secondary ignition treatment of the sintering bed entering the sintering stage is calculated by using the ignition intensity of the ignition furnace, the residual carbon rate of the sintering bed, the thickness of the sintering bed, and the amount of solid fuel added to the sintering bed as independent variables. The specific calculation formula is shown in the above formula (5).

[0042] Furthermore, when a secondary ignition process is required, in order to further achieve the best ignition effect of the two ignitions, it is also necessary to control the ignition duration of the first ignition and the time interval between the two ignitions. That is, by using the ignition intensity of the ignition furnace, the residual carbon rate of the material layer, the thickness of the sintering material layer, and the amount of solid fuel added in the sintering material as independent variables, the subsequent sintering material (referring to the sintering material that has not yet passed through the head ignition furnace) is ignited once, and a secondary ignition is performed after a specified time. The specific calculation formula for the ignition interval is given in formula (6) above.

[0043] Furthermore, under the premise of ensuring the complete combustion of residual carbon in the sinter and minimizing ignition energy consumption and carbon emissions, an oxygen injection treatment can be performed on the sinter after the first ignition treatment and before the second ignition treatment, and / or a second oxygen injection treatment can be performed on the sinter after the second ignition treatment. At the same time, the amount of oxygen injected for the two oxygen injection treatments should be reasonably controlled according to the actual working conditions. That is to say, in the two ignition treatment mode, one oxygen injection treatment and / or a second oxygen injection treatment can be added at will. The specific calculation formulas for the amount of oxygen injected for each of the two oxygen injection treatments are shown in the above formulas (7)-(8).

[0044] This invention also provides a sintering system with a tail section monitoring mechanism for the aforementioned sintering method. This system includes a sintering machine (including a frame, trolley, fume hood, wind box, etc., i.e., any type of sintering machine in the prior art) and, sequentially arranged on the sintering machine along the direction of the sintering material, a primary ignition furnace, a primary oxygen injection mechanism, a secondary ignition furnace, a secondary oxygen injection mechanism, and a tail section monitoring mechanism located downstream of the sintering machine tail. Depending on the operating conditions, it can meet the needs of various sintering modes (such as primary ignition + primary oxygen injection mode, primary ignition + secondary ignition mode, primary ignition + primary oxygen injection + secondary ignition + secondary oxygen injection mode, etc.), enabling low-energy-consumption sintering of sintered mixtures with different properties while ensuring the quality of the sintered product.

[0045] In this invention, the existing ignition burners in sintering ignition and heat preservation furnaces use gas ignition, resulting in a distinct columnar flame with varying temperatures in the outer flame, inner flame, and flame core. Furthermore, the temperature difference between areas with and without flame is significant, easily leading to uneven ignition of the iron ore sintering material surface. This frequently causes localized over-melting or under-melting, resulting in increased overall sintering energy consumption and carbon emissions. To address this issue, this invention designs a rotatable and adjustable ignition burner. Specifically, the upper part of the burner is connected to the furnace body via an angle adjustment mechanism, and the lower end of the burner extends into a pre-designed through-hole in the furnace body, narrow at the top and wide at the bottom. The angle adjustment mechanism mainly includes a fixing plate for securing the burner and at least two telescopic rods (the telescopic rod structure can be any existing technology capable of lifting and lowering, for example, the telescopic rod includes a drive motor, a cylinder, and a piston rod; the cylinder is located on the top surface of the furnace body, and the drive motor is located on the cylinder). One side is connected to the cylinder, and the bottom end of the piston rod is connected to the cylinder, while its top end is hinged to the bottom surface of the fixed plate. By adjusting the height of the two telescopic rods, the fixed plate is tilted at a certain angle relative to the horizontal plane, which in turn causes the burner to tilt to a certain extent in the vertical direction. By adjusting the alternating height of the two telescopic rods, the burner can swing back and forth in the vertical direction, allowing the high-temperature flame sprayed by the burner to move back and forth on the sintering material surface, thereby improving the heat transfer uniformity of the sintering material surface and ensuring the uniformity of ignition of the sintering material. It should be noted that, depending on the size of the sintering material surface, the sintering ignition furnace is designed with several evenly distributed, angle-adjustable burners to ensure uniform ignition of the entire sintering material surface.

[0046] In this invention, the running speed of the sintering material is generally relatively stable during the sintering process. However, due to fluctuations in the composition of the sintering material, when two-stage ignition is required, to achieve precise control of the time interval between the two ignitions, both the primary ignition furnace and / or the secondary ignition furnace are designed to be freely movable along the running direction of the sintering material on the sintering machine. That is, given a fixed running speed of the sintering material, the time interval between the two ignitions is adjusted by changing the distance between the primary and secondary ignition furnaces. Preferably, only the secondary ignition furnace is designed as a freely movable mechanism. Specifically, the secondary ignition furnace is supported and moved by a wheeled frame with wheels. The support points are the frame of the sintering machine or the ground. If necessary, guide rails can be laid on the frame of the sintering machine or the ground to ensure the stable and rapid horizontal movement of the secondary ignition furnace.

[0047] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0048] 1. This invention accurately grasps the residual carbon rate of the material layer through online monitoring and feedback. Based on the relationship between the residual carbon rate of the material layer and the surface return rate, the sintering ignition process is innovatively optimized and adjusted to achieve the combustion and removal of residual carbon with low cost, low energy consumption, and low carbon emissions. This can significantly reduce the surface return rate and effectively improve the sintering yield.

[0049] 2. This invention reduces the surface return rate by lowering the residual carbon content of the material layer, while also eliminating the secondary sintering reaction caused by residual carbon in the subsequent cooling process of the hot finished ore, avoiding material jamming at the bottom of the annular cooler, and improving production safety.

[0050] 3. The system provided by this invention has a simple structure, and through the design of the angle-adjustable ignition burner, it can achieve uniform heating of the sintering material surface, avoid the phenomenon of local over-melting or over-rawness of the raw material surface, and help reduce the return ore rate and increase the sintering yield. Attached Figure Description

[0051] Figure 1 This is a schematic diagram of the sintering method of the present invention.

[0052] Figure 2 This is a system structure diagram of the method used in this invention.

[0053] Figure 3 This is an enlarged schematic diagram of the ignition furnace of the system described in this invention.

[0054] Attached reference numerals: 1: Sintering machine; 2: Material feeder; 3: Primary ignition furnace; 4: Primary oxygen injection mechanism; 5: Secondary ignition furnace; 6: Secondary oxygen injection mechanism; 7: Tail section monitoring mechanism; 8: Furnace body; 9: Burner; 10: Burner through hole; 11: Fixing plate; 12: Telescopic rod; 13: Wheeled upright. Detailed Implementation

[0055] The technical solution of the present invention will be illustrated below with examples. The scope of protection sought by the present invention includes, but is not limited to, the following embodiments.

[0056] Example 1

[0057] like Figures 1-2 As shown, a method for sintering with low return ore density:

[0058] 1) The trolley containing the sintering material runs from the head to the tail of the sintering machine 1. During this process, the sintering material is ignited by the primary ignition furnace 3 and enters the sintering stage. After sintering is completed, the hot sintered finished ore is discharged from the tail of the sintering machine 1.

[0059] 2) At the tail of sintering machine 1, the vertical cross-section of the hot-sintered finished ore is monitored in real time by a tail section monitoring mechanism to obtain cross-sectional data including the brightness, chroma, continuity, thickness, and height of the red layer. Then, the surface return rate is calculated based on the obtained cross-sectional data, and finally, the surface carbon consumption and residual carbon rate are calculated based on the surface return rate.

[0060] 3) Based on the residual carbon rate of the material layer, the sintering material entering the sintering stage is treated with oxygen by a single oxygen injection mechanism 4 to reduce the amount of returned ore in the finished ore.

[0061] Example 2

[0062] like Figures 1-2 As shown, a method for sintering with low return ore density:

[0063] 1) The trolley containing the sintering material runs from the head to the tail of the sintering machine 1. During this process, the sintering material is ignited by the primary ignition furnace 3 and enters the sintering stage. After sintering is completed, the hot sintered finished ore is discharged from the tail of the sintering machine 1.

[0064] 2) At the tail of sintering machine 1, the vertical cross-section of the hot-sintered finished ore is monitored in real time by a tail section monitoring mechanism to obtain cross-sectional data including the brightness, chroma, continuity, thickness, and height of the red layer. Then, the surface return rate is calculated based on the obtained cross-sectional data, and finally, the surface carbon consumption and residual carbon rate are calculated based on the surface return rate.

[0065] 3) Based on the residual carbon rate of the material layer, the sintering material entering the sintering stage is subjected to secondary ignition treatment using a secondary ignition furnace 5 to reduce the amount of returned ore in the finished ore.

[0066] Example 3

[0067] like Figures 1-2As shown, a method for sintering with low return ore density:

[0068] 1) The trolley containing the sintering material runs from the head to the tail of the sintering machine 1. During this process, the sintering material is ignited by the primary ignition furnace 3 and enters the sintering stage. After sintering is completed, the hot sintered finished ore is discharged from the tail of the sintering machine 1.

[0069] 2) At the tail of sintering machine 1, the vertical cross-section of the hot-sintered finished ore is monitored in real time by a tail section monitoring mechanism to obtain cross-sectional data including the brightness, chroma, continuity, thickness, and height of the red layer. Then, the surface return rate is calculated based on the obtained cross-sectional data, and finally, the surface carbon consumption and residual carbon rate are calculated based on the surface return rate.

[0070] 3) Based on the residual carbon rate of the material layer, the sintering material entering the sintering stage is subjected to a first oxygen injection treatment by a primary oxygen injection mechanism 4 and a secondary ignition treatment by a secondary ignition furnace 5 in order to reduce the amount of returned ore in the finished ore.

[0071] Example 4

[0072] like Figures 1-2 As shown, a method for sintering with low return ore density:

[0073] 1) The trolley containing the sintering material runs from the head to the tail of the sintering machine 1. During this process, the sintering material is ignited by the primary ignition furnace 3 and enters the sintering stage. After sintering is completed, the hot sintered finished ore is discharged from the tail of the sintering machine 1.

[0074] 2) At the tail of sintering machine 1, the vertical cross-section of the hot-sintered finished ore is monitored in real time by a tail section monitoring mechanism to obtain cross-sectional data including the brightness, chroma, continuity, thickness, and height of the red layer. Then, the surface return rate is calculated based on the obtained cross-sectional data, and finally, the surface carbon consumption and residual carbon rate are calculated based on the surface return rate.

[0075] 3) Based on the residual carbon rate of the material layer, the sintering material entering the sintering stage is subjected to secondary ignition treatment using a secondary ignition furnace 5 and secondary oxygen injection treatment using a secondary oxygen injection mechanism 6 in sequence to reduce the amount of returned ore in the finished ore.

[0076] Example 5

[0077] like Figures 1-2 As shown, a method for sintering with low return ore density:

[0078] 1) The trolley containing the sintering material runs from the head to the tail of the sintering machine 1. During this process, the sintering material is ignited by the primary ignition furnace 3 and enters the sintering stage. After sintering is completed, the hot sintered finished ore is discharged from the tail of the sintering machine 1.

[0079] 2) At the tail of sintering machine 1, the vertical cross-section of the hot-sintered finished ore is monitored in real time by a tail section monitoring mechanism to obtain cross-sectional data including the brightness, chroma, continuity, thickness, and height of the red layer. Then, the surface return rate is calculated based on the obtained cross-sectional data, and finally, the surface carbon consumption and residual carbon rate are calculated based on the surface return rate.

[0080] 3) Based on the residual carbon rate of the material layer, the sintering material entering the sintering stage is subjected to a first oxygen injection treatment by a primary oxygen injection mechanism 4, a secondary ignition treatment by a secondary ignition furnace 5, and a secondary oxygen injection treatment by a secondary oxygen injection mechanism 6 in sequence to reduce the amount of returned ore in the finished ore.

[0081] Example 6

[0082] A sintering system with a tail section monitoring mechanism, such as Figure 2 As shown, the system includes a sintering machine 1, a feeding machine 2, a primary ignition furnace 3, a primary oxygen injection mechanism 4, a secondary ignition furnace 5, a secondary oxygen injection mechanism 6, and a tail section monitoring mechanism 7. According to the direction of the sintering mixture, the feeding machine 2, primary ignition furnace 3, primary oxygen injection mechanism 4, secondary ignition furnace 5, and secondary oxygen injection mechanism 6 are sequentially arranged on the fume hood of the sintering machine 1. The tail section monitoring mechanism 7 is located downstream of the tail of the sintering machine 1.

[0083] Example 7

[0084] Repeat Example 6, as follows Figure 2As shown, the primary ignition furnace 3 and the secondary ignition furnace 5 have the same structure, both including a furnace body 8 and burners 9. The furnace body 8 is mounted on the fume hood of the sintering machine 1, and a through-hole 10, narrow at the top and wide at the bottom, is provided on the top of the furnace body 8. The bottom end of the burner through-hole 10 is connected to the inner cavity of the fume hood of the sintering machine 1. The upper part of the burner 9 is connected to the top of the furnace body 8 through a fixing plate 11 and a telescopic rod 12, and the lower end of the burner 9 extends into the burner through-hole 10 and extends to the bottom end of the burner through-hole 10. The tilt angle of the burner 9 in the vertical plane is adjusted by the fixing plate 11 and the telescopic rod 12. The furnace body 8 is connected to the frame of the sintering machine 1 or to the ground through a wheeled support frame 13. In the horizontal direction of the sintering mixture, the horizontal position of the furnace body 8 on the fume hood of the sintering machine 1 is adjusted by the wheeled support frame 13. Both the primary ignition furnace 3 and the secondary ignition furnace 5 have multiple angle-adjustable burners 9, which are evenly distributed on the furnace body 8. The primary oxygen injection mechanism 4 and the secondary oxygen injection mechanism 6 have the same structure, each including at least one oxygen injection pipe with an independent throttle valve. The tail section monitoring mechanism 7 is an industrial camera.

[0085] Application Example 1

[0086] The system described in Example 7 was used to sinter a batch of sintered material, wherein the sintered material layer thickness H was 580 mm, the amount of solid fuel added β in the sintered material was 48 kg / t, and the ignition intensity ω of the ignition furnace was... 点火 20 MJ / m 2 The running speed V of the sinter is 0.03 m / s, and the first ignition time is 90 s. Under the current operating conditions, the following were detected in the vertical cross-section of the hot-sintered finished ore in this batch: the brightness α of the cross-section red layer is 0.8 degrees, the chromaticity γ of the cross-section red layer is 1.2 degrees, the continuity θ of the cross-section red layer is 75%, the thickness δ of the cross-section red layer is 38 mm, the height h of the cross-section red layer is 490 mm, the unit carbon consumption j of the sinter is 0.05 kg / kg, and the total amount of surface sinter is Q. 表层 The value is 500 kg, the first return ore constant a is 1.5, the second return ore constant b is 0.05, and the carbon consumption correction coefficient c is 1.6.

[0087] Under the current operating conditions, the surface return rate C is calculated according to formulas (1)-(3). 返矿 Surface carbon consumption W 耗碳 and surface residual carbon rate C 残碳 Real-time values:

[0088]

[0089] W 耗碳 =Q 表层 ×(1-C 返矿 )×j×c=500×(1-0.105)×0.05×1.6=35.8

[0090]

[0091] That is, the surface ore return rate under the current operating conditions is 0.105%, and the surface carbon consumption is 35.8 kg / m³. 2 The surface residual carbon rate is approximately 0.25%; due to C 残碳 If the value is less than 0.3, the current sintering process is adjusted to the sintering mode described in Example 1. The operating constant d for single oxygen injection is set to 1.2, and the amount of oxygen required for single oxygen injection is calculated using formula (4):

[0092]

[0093] That is, the amount of oxygen required for single-aeration treatment under the current operating conditions is 0.72m³. 3 / s. After a sintering process that included one ignition and one oxygen injection treatment, the residual carbon rate in the sintered finished product was detected to be 0.13%, and the final surface return rate was approximately 0.089%.

[0094] Application Example 2

[0095] The system described in Example 7 was used to sinter a batch of sintered material, wherein the sintered material layer thickness H was 580 mm, the amount of solid fuel added to the sintered material β was 50 kg / t, and the ignition intensity of the ignition furnace was ω. 点火 21 MJ / m 2 The running speed V of the sinter is 0.03 m / s, and the first ignition time is 90 s. Under the current operating conditions, the following were detected in the vertical cross-section of the hot-sintered finished ore in this batch: the brightness α of the cross-section red layer is 1 degree, the chromaticity γ of the cross-section red layer is 1.5 degrees, the continuity θ of the cross-section red layer is 75%, the thickness δ of the cross-section red layer is 40 mm, the height h of the cross-section red layer is 500 mm, the unit carbon consumption j of the sinter is 0.05 kg / kg, and the total amount of surface sinter is Q. 表层 The weight is 450 kg, the first return ore constant a is 1.2, the second return ore constant b is 0.07, and the carbon consumption correction coefficient c is 1.2.

[0096] Under the current operating conditions, the surface return rate C is calculated according to formulas (1)-(3). 返矿 Surface carbon consumption W 耗碳 and surface return rate C 残碳 Real-time values:

[0097]

[0098] W 耗碳 =Q 表层 ×(1-C 返矿)×j×c=450×(1-0.308)×0.05×1.2=18.68

[0099]

[0100] That is, the surface ore return rate under the current operating conditions is approximately 0.308%, and the surface carbon consumption is 18.68 kg / m³. 2 The surface residual carbon rate is approximately 0.63%; due to C 残碳 If the value is greater than 0.3, then the current sintering process is adjusted to the sintering mode described in Example 2: the carbon-oxygen burnout ratio coefficient E is set. 碳氧 =1.5, oxygen intake coefficient of sintered material surface λ = 28, second ignition duration condition constant e = 90, ignition interval condition constant f = 4, and the second ignition duration and the time interval between the two ignitions required for the second ignition process are calculated by formulas (5), (6), and (7):

[0101]

[0102] The time interval between the two ignitions under the current operating conditions is approximately 225 seconds, and the secondary ignition time required for the secondary ignition process is approximately 41 seconds. After the sintering process, which includes the first ignition and the second ignition, the residual carbon rate in the sintered finished product was detected to be 0.11%, and the final surface return rate was 0.076%.

[0103] Application Example 3

[0104] The system described in Example 7 was used to sinter a batch of sintered material, wherein the sintered material layer thickness H was 680 mm, the amount of solid fuel added β in the sintered material was 55 kg / t, and the ignition intensity of the ignition furnace was ω. 点火 25 MJ / m 2 The running speed V of the sinter is 0.05 m / s, and the first ignition time is 90 s. Under the current operating conditions, the following were detected in the vertical cross-section of the hot-sintered finished ore in this batch: the brightness α of the cross-section red layer is 1.5 degrees, the chromaticity γ of the cross-section red layer is 1 degree, the continuity θ of the cross-section red layer is 80%, the thickness δ of the cross-section red layer is 35 mm, the height h of the cross-section red layer is 600 mm, the unit carbon consumption j of the sinter is 0.05 kg / kg, and the total amount of surface sinter is Q. 表层 The weight is 500 kg, the first return ore constant a is 1.5, the second return ore constant b is 0.05, and the carbon consumption correction coefficient c is 1.5.

[0105] Under the current operating conditions, the surface return rate C is calculated according to formulas (1)-(3). 返矿 Surface carbon consumption W 耗碳 and surface return rate C 返矿 For the actual value:

[0106]

[0107] W 耗碳 =Q 表层 ×(1-C 返矿 )×j×c=500×(1-0.163)×0.05×1.5≈31.4

[0108]

[0109] That is, the surface ore return rate under the current operating conditions is approximately 0.163%, and the surface carbon consumption is approximately 31.4 kg / m³. 2 The surface residual carbon rate is approximately 0.43%; due to C 残碳 If the value is less than 0.5, the current sintering process is adjusted to the sintering mode described in Example 1: the operating constant d for single oxygen injection is set to 1.1, and the amount of oxygen required for oxygen injection treatment is calculated using formula (4):

[0110]

[0111] That is, under the current operating conditions, the amount of oxygen required for single-aeration treatment is approximately 1.04 m³. 3 / s. After a sintering process that included one ignition and one oxygen injection treatment, the residual carbon rate in the sintered finished product was detected to be 0.26%, and the final surface return rate was 0.11%.

[0112] Application Example 4

[0113] The system described in Example 7 was used to sinter a batch of sintered material, wherein the sintered material layer thickness H was 680 mm, the amount of solid fuel added to the sintered material β was 60 kg / t, and the ignition intensity ω of the ignition furnace was... 点火 24 MJ / m 2 The running speed V of the sinter is 0.04 m / s, and the first ignition time is 90 s. Under the current operating conditions, the following were detected in the vertical cross-section of the hot-sintered finished ore in this batch: the brightness α of the cross-section red layer is 3.6 degrees, the chromaticity γ of the cross-section red layer is 3 degrees, the continuity θ of the cross-section red layer is 50%, the thickness δ of the cross-section red layer is 40 mm, the height h of the cross-section red layer is 550 mm, the unit carbon consumption j of the sinter is 0.05 kg / kg, and the total amount of surface sinter is Q. 表层 The weight is 480 kg. The first return ore constant a is 1.4, and the second return ore constant b is 0.01. The carbon consumption correction factor c is taken as 1.

[0114] Under the current operating conditions, the surface return rate C is calculated according to formulas (1)-(3). 返矿 Surface carbon consumption W 耗碳 and surface return rate C 返矿 Real-time values:

[0115]

[0116] W 耗碳 =Q 表层 ×(1-C 返矿 )×j×c=480×(1-0.669)×0.05×1≈7.94

[0117]

[0118] That is, the surface ore return rate under the current operating conditions is approximately 0.669%, and the surface carbon consumption is approximately 7.94 g / m³. 2 The surface residual carbon rate is approximately 0.87%; due to C 残碳 If the value is greater than 0.5, then the current sintering process is adjusted to the sintering mode described in Example 2: the carbon-oxygen burnout ratio coefficient E is set. 碳氧 =1.8, oxygen intake coefficient of sintered material surface λ = 26, second ignition time condition constant e = 90, ignition interval condition constant f = 4, and the second ignition time t required for the second ignition treatment is calculated by formulas (5), (6), and (7). 二次 and the time interval t between the two ignitions 间隔 :

[0119]

[0120]

[0121] The time interval between the two ignitions under the current operating conditions is approximately 361 seconds, and the secondary ignition time required for the secondary ignition process is approximately 46 seconds. After the sintering process, which includes the first ignition and the second ignition, the residual carbon rate in the sintered finished product was detected to be 0.38%, and the final surface return rate was 0.21%.

[0122] Application Example 5

[0123] The system described in Example 7 was used to sinter a batch of sintered material, wherein the sintered material layer thickness H was 680 mm, the amount of solid fuel added to the sintered material β was 60 kg / t, and the ignition intensity ω of the ignition furnace was... 点火 24 MJ / m 2 The running speed V of the sinter is 0.04 m / s, and the first ignition time is 90 s. Under the current operating conditions, the following were detected in the vertical cross-section of the hot-sintered finished ore in this batch: the brightness α of the cross-section red layer is 3.1 degrees, the chromaticity γ of the cross-section red layer is 3.8 degrees, the continuity θ of the cross-section red layer is 52%, the thickness δ of the cross-section red layer is 42 mm, the height h of the cross-section red layer is 555 mm, the unit carbon consumption j of the sinter is 0.05 kg / kg, and the total amount of surface sinter is Q. 表层The weight is 480 kg, the first return ore constant a is 1.4, the second return ore constant b is 0.01, and the carbon consumption correction coefficient c is 1.

[0124] Under the current operating conditions, the surface return rate C is calculated according to formulas (1)-(3). 返矿 Surface carbon consumption W 耗碳 and surface return rate C 返矿 For the actual value:

[0125]

[0126] W 耗碳 =Q 表层 ×(1-C 返矿 )×j×c=480×(1-0.72)×0.05×1≈6.72

[0127]

[0128] That is, the surface ore return rate under the current operating conditions is approximately 0.72%, and the surface carbon consumption is approximately 6.72 g / m³. 2 The surface residual carbon rate is approximately 0.888%; due to C 残碳 If the value is greater than 0.5, then the current sintering process is adjusted to the sintering mode described in Example 3: the carbon-oxygen burnout ratio coefficient E is set. 碳氧 =1.8, oxygen intake coefficient of sintered material surface λ = 26, second ignition time condition constant e = 90, ignition interval condition constant f = 3, burnout coefficient ζ = 0.2, carbon-oxygen replacement coefficient π = 18; and the second ignition time t required for the second ignition treatment is calculated by formulas (5), (6), (7), and (8). 二次 The time interval t between two ignitions 间隔 And the amount of oxygen injected in a single treatment, Q. 一次氧 :

[0129]

[0130]

[0131] That is, the time interval between the two ignitions under the current operating conditions is approximately 277 seconds, the secondary ignition time required for the secondary ignition process is approximately 47 seconds, and the amount of oxygen injected for the primary oxygen injection process is 1.96 m³. 3 / s. After a sintering process that included one ignition, one oxygen injection, and a second ignition, the residual carbon rate in the sintered finished product was detected to be 0.32%, and the final surface return rate was 0.17%.

[0132] Application Example 6

[0133] The system described in Example 7 was used to sinter a batch of sintered material, wherein the sintered material layer thickness H was 680 mm, the amount of solid fuel added to the sintered material β was 60 kg / t, and the ignition intensity ω of the ignition furnace was... 点火 24 MJ / m 2 The running speed V of the sinter is 0.04 m / s, and the first ignition time is 90 s. Under the current operating conditions, the following were detected in the vertical cross-section of the hot-sintered finished ore in this batch: the brightness α of the cross-section red layer is 3.1 degrees, the chromaticity γ of the cross-section red layer is 3.8 degrees, the continuity θ of the cross-section red layer is 52%, the thickness δ of the cross-section red layer is 42 mm, the height h of the cross-section red layer is 555 mm, the unit carbon consumption j of the sinter is 0.05 kg / kg, and the total amount of surface sinter is Q. 表层 The weight is 480 kg, the first return ore constant a is 1.4, the second return ore constant b is 0.01, and the carbon consumption correction coefficient c is 1.

[0134] Under the current operating conditions, the surface return rate C is calculated according to formulas (1)-(3). 返矿 Surface carbon consumption W 耗碳 and surface return rate C 返矿 For the actual value:

[0135]

[0136] W 耗碳 =Q 表层 ×(1-C 返矿 )×j×c=480×(1-0.72)×0.05×1≈6.72

[0137]

[0138] That is, the surface ore return rate under the current operating conditions is approximately 0.72%, and the surface carbon consumption is approximately 6.72 g / m³. 2 The surface residual carbon rate is approximately 0.888%; due to C 残碳 If the value is greater than 0.5, then the current sintering process is adjusted to the sintering mode described in Example 4: the carbon-oxygen burnout ratio coefficient E is set. 碳氧 =1.8, oxygen intake coefficient of sintered material surface λ = 26, second ignition time condition constant e = 90, ignition interval condition constant f = 3, burnout coefficient ζ = 0.2, carbon-oxygen replacement coefficient π = 18; and the second ignition time t required for the second ignition treatment is calculated by formulas (5), (6), (7), and (9). 二次 The time interval t between two ignitions 间隔 And the amount of secondary oxygen injection Q required during secondary oxygen injection treatment. 二次氧 :

[0139]

[0140]

[0141] That is, the time interval between the two ignitions under the current operating conditions is approximately 277 seconds, the secondary ignition time required for the secondary ignition process is approximately 47 seconds, and the secondary oxygen injection volume required for the secondary oxygen injection process is approximately 1.44 m³. 3 / s. After a sintering process that included primary ignition, secondary ignition, and secondary oxygen injection, the residual carbon rate in the sintered finished product was detected to be 0.26%, and the final surface return rate was 0.12%.

[0142] Application Example 7

[0143] The system described in Example 7 was used to sinter a batch of sintered material, wherein the sintered material layer thickness H was 680 mm, the amount of solid fuel added to the sintered material β was 60 kg / t, and the ignition intensity ω of the ignition furnace was... 点火 24 MJ / m 2 The running speed V of the sinter is 0.04 m / s, and the first ignition time is 90 s. Under the current operating conditions, the following were detected in the vertical cross-section of the hot-sintered finished ore in this batch: the brightness α of the cross-section red layer is 3.1 degrees, the chromaticity γ of the cross-section red layer is 3.8 degrees, the continuity θ of the cross-section red layer is 52%, the thickness δ of the cross-section red layer is 42 mm, the height h of the cross-section red layer is 555 mm, the unit carbon consumption j of the sinter is 0.05 kg / kg, and the total amount of surface sinter is Q. 表层 The weight is 480 kg, the first return ore constant a is 1.4, the second return ore constant b is 0.01, and the carbon consumption correction coefficient c is 1.

[0144] Under the current operating conditions, the surface return rate C is calculated according to formulas (1)-(3). 返矿 Surface carbon consumption W 耗碳 and surface return rate C 返矿 For the actual value:

[0145]

[0146] W 耗碳 =Q 表层 ×(1-C 返矿 )×j×c=480×(1-0.72)×0.05×1≈6.72

[0147]

[0148] That is, the surface ore return rate under the current operating conditions is approximately 0.72%, and the surface carbon consumption is approximately 6.72 g / m³. 2 The surface residual carbon rate is approximately 0.888%; due to C 残碳If the value is greater than 0.5, then the current sintering process is adjusted to the sintering mode described in Example 5: the carbon-oxygen burnout ratio coefficient E is set. 碳氧 =1.8, oxygen intake coefficient of sintered material surface λ = 26, second ignition time condition constant e = 90, ignition interval condition constant f = 3, burnout coefficient ζ = 0.2, carbon-oxygen replacement coefficient π = 18; and the second ignition time t required for the second ignition treatment is calculated by formulas (5), (6), (7), (8), and (9). 二次 The time interval t between two ignitions 间隔 The amount of oxygen injected in a single treatment, Q. 一次氧 And the amount of secondary oxygen injected, Q, required during secondary oxygen injection treatment. 二次氧 :

[0149]

[0150] That is, the time interval between the two ignitions under the current operating conditions is approximately 277 seconds, the secondary ignition time required for the secondary ignition process is approximately 47 seconds, and the amount of oxygen injected for the primary oxygen injection process is 1.96 m³. 3 / s, the secondary oxygen injection volume required for secondary oxygen injection treatment is approximately 1.44m³ / s. 3 / s. After a sintering process that included one ignition + one oxygen injection + two ignitions + two oxygen injections, the residual carbon rate in the sintered finished product was detected to be 0.16%, and the final surface return rate was 0.08%.

[0151] Comparative Example 1

[0152] Example 1 was repeated, but with only one ignition treatment. The residual carbon content in the sintered product was detected to be approximately 0.105%, and the final surface return rate was 0.27%.

[0153] Comparative Example 2

[0154] Example 3 was repeated, but with only one ignition treatment. The residual carbon content in the sintered product was detected to be approximately 0.308%, and the final surface return rate was 0.39%.

Claims

1. A method for sintering low-return ore, characterized in that: The method includes: 1) The trolley containing the sintering material runs from the head to the tail of the sintering machine. During this process, the sintering material is ignited by the furnace at the head of the machine and enters the sintering stage. The hot sintered finished ore formed after sintering is discharged from the tail of the sintering machine. 2) Monitor the vertical cross-section of the hot-sintered finished ore in real time at the tail of the sintering machine to obtain cross-sectional data including the brightness, chroma, continuity, thickness, and height of the red layer; then calculate the surface return rate based on the obtained cross-sectional data, and finally calculate the surface carbon consumption and residual carbon rate based on the surface return rate. 3) Based on the residual carbon content of the material layer, oxygen injection treatment or secondary ignition treatment is carried out on the sintering material entering the sintering stage to reduce the amount of returned ore in the finished ore.

2. The method according to claim 1, characterized in that: In step 2), the surface ore return rate is calculated based on the obtained cross-sectional data: The formula for calculating the surface ore return rate using cross-sectional data as a variable is as follows: In equation (1), C 返矿 α is the surface ore return rate, %; γ is the cross-sectional red layer brightness, degrees; γ is the cross-sectional red layer chromaticity, degrees; θ is the cross-sectional red layer continuity, %; δ is the cross-sectional red layer thickness, mm; h is the cross-sectional red layer height, mm; a is the first ore return constant, with a value of 0.8 to 2; b is the second ore return constant, with a value of 0.01 to 0.

1.

3. The method according to claim 1 or 2, characterized in that: In step 2), the surface carbon consumption and residual carbon rate are calculated sequentially based on the surface return rate: the surface carbon consumption is calculated using the surface return rate as a variable, and then the residual carbon rate is calculated using the surface carbon consumption as a variable. W 耗碳 =Q 表层 ×(1-C 返矿 )×j×c (2); In equations (2)-(3), W 耗碳 Surface carbon consumption, kg / m 2 ; C 残碳 The residual carbon content of the material layer is expressed as a percentage (%); Q 表层 The total amount of surface sintering material, in kg; C 返矿 denoted as surface return rate (%); j represents the unit carbon consumption of the sinter (kg / kg); β represents the amount of solid fuel added to the sinter (kg / t); and c represents the carbon consumption correction factor, ranging from 1 to 5.

4. The method according to any one of claims 1-3, characterized in that: Step 3) includes: 301) When the thickness H of the sintered material layer is less than 600 mm and the residual carbon content C of the material layer is less than 600 mm, the sintered material layer is less than 600 mm. 残碳 When <0.3% or when the sintered material layer thickness H≥600mm and the residual carbon content C of the material layer is <0.3%, 残碳 When the content is <0.5%, the sintering material entering the sintering stage is only treated with oxygen spraying. 302) When the thickness H of the sintered material layer is less than 600 mm and the residual carbon content C of the material layer is less than 600 mm, the sintered material layer is less than 600 mm. 残碳 When ≥0.3% or when the sintered material layer thickness H≥600mm and the residual carbon content C of the material layer is... 残碳 When the content is ≥0.5%, the sintering material entering the sintering stage is subjected to secondary ignition treatment.

5. The method according to claim 4, characterized in that: In step 301), based on the ignition intensity of the ignition furnace and the residual carbon content of the material layer, the amount of oxygen required for oxygen injection when only oxygen injection is applied to the sintering material entering the sintering stage is calculated. Therefore: In equation (4), Q 氧气 m is the amount of oxygen required for oxygen injection when only oxygen injection is performed. 3 / s; β is the amount of solid fuel added to the sinter, kg / t; ω 点火 The ignition intensity of the furnace, in MJ / m³ 2 d is the operating constant for single oxygen injection, with a value of 1 to 5.

6. The method according to claim 4 or 5, characterized in that: In step 302), the ignition time required for secondary ignition treatment of the sinter entering the sintering stage is calculated based on the ignition intensity of the ignition furnace, the residual carbon rate of the sintering bed, the thickness of the sintering bed, and the amount of solid fuel added to the sintering material. Then: In equation (5), t 二次 The duration of secondary ignition is s; ω 点火 The ignition intensity of the furnace, in MJ / m³ 2 ; β is the amount of solid fuel added to the sinter, kg / t; e is the second ignition duration constant, with a value of 10 to 100.

7. The method according to claim 6, characterized in that: In step 302): the time interval required for the ignition furnace to ignite the sintering material twice is calculated based on the ignition intensity of the ignition furnace, the residual carbon content of the sintering layer, the thickness of the sintering layer, and the amount of solid fuel added to the sintering material. Therefore: In equation (6), t 间隔 The time interval between two ignitions is s; E 碳氧 λ is the carbon-oxygen burnout ratio coefficient, with a value of 0.5 to 2; V is the running speed of the sinter, m / s; λ is the oxygen intake coefficient of the sinter surface, with a value of 20 to 40; f is the ignition interval constant, with a value of 1 to 10.

8. The method according to claim 7, characterized in that: After the first ignition treatment and before the second ignition treatment, the sinter was subjected to an oxygen injection treatment, and / or, after the second ignition treatment, the sinter was subjected to a second oxygen injection treatment; based on the residual carbon content of the material layer, the amount of solid fuel added to the sinter, the duration of the first ignition, and the duration of the second ignition, the amount of oxygen required for the first and second oxygen injection treatments is calculated, and then: In equations (7)-(8), Q 一次氧 The amount of oxygen injected in one cycle, m 3 / s;t 一次 The duration of one ignition cycle, s; Q 二次氧 This refers to the secondary oxygen injection volume, m 3 / s; ζ is the burnout coefficient, with a value of 0.1 to 1; π is the carbon-oxygen replacement coefficient, with a value of 10 to 20.

9. The method according to any one of claims 1-8, characterized in that: The method employs a sintering system with a tail section monitoring mechanism: the sintering system with a tail section monitoring mechanism includes a sintering machine (1), a feeding machine (2), a primary ignition furnace (3), a primary oxygen injection mechanism (4), a secondary ignition furnace (5), a secondary oxygen injection mechanism (6), and a tail section monitoring mechanism (7); according to the direction of the sintering mixture, the feeding machine (2), the primary ignition furnace (3), the primary oxygen injection mechanism (4), the secondary ignition furnace (5), and the secondary oxygen injection mechanism (6) are sequentially arranged on the fume hood of the sintering machine (1); the tail section monitoring mechanism (7) is located on the downstream side of the tail of the sintering machine (1); Preferably, the tail section monitoring mechanism (7) is an industrial camera.

10. The method according to claim 9, characterized in that: The primary ignition furnace (3) and the secondary ignition furnace (5) have the same structure, both including a furnace body (8) and a burner (9); the furnace body (8) is set on the fume hood of the sintering machine (1), and a through burner through hole (10) with a narrow top and wide bottom is opened on the top of the furnace body (8), the bottom end of the burner through hole (10) is connected to the inner cavity of the fume hood of the sintering machine (1); the upper part of the burner (9) is connected to the top of the furnace body (8) through a fixing plate (11) and a telescopic rod (12), and the lower end of the burner (9) extends into the burner through hole (10) and extends to the burner through hole (12). The bottom end of 0); the tilt angle of the burner (9) in the vertical plane is adjusted by the fixing plate (11) and the telescopic rod (12); preferably, the furnace body (8) is connected to the frame of the sintering machine (1) or to the ground by the wheeled upright (13), and the horizontal position of the furnace body (8) on the sintering machine (1) fume hood is adjusted by the wheeled upright (13) in the horizontal direction of the sintering mixture operation; preferably, both the primary ignition furnace (3) and the secondary ignition furnace (5) have multiple angle-adjustable burners (9), and the multiple burners (9) are evenly distributed on the furnace body (8); and / or The primary oxygen injection mechanism (4) and the secondary oxygen injection mechanism (6) have the same structure, both including at least one oxygen injection pipe with an independent throttle valve.

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