Sintering finish line adjusting method and system based on sintering abnormity of tail section

Abstract

The invention provides a sintering finish line adjusting method and system based on sintering abnormity of a tail section, and the method comprises the steps: obtaining a visible light imaging picture of the current sintering ore tail section, judging whether the current state is an abnormal sintering state or not according to the visible light imaging picture, and when the current sintering state is the abnormal sintering state, adjusting the sintering finish line. According to the expected sintering finish line and a pre-established position flow algorithm model, a first fuel gas injection flow calculation value corresponding to the fact that the actual sintering finish line is adjusted to the expected sintering finish line in the current state is determined, and when the first fuel gas injection flow calculation value is within the effective flow adjustment range, the actual sintering finish line is adjusted to the expected sintering finish line; and the gas injection adjusting valve is adjusted to adjust the current gas injection flow to the first gas injection flow calculated value. According to the method and the device, when the current state is judged to be the sintering state abnormity through the visible light image, the flow adjusting value corresponding to adjusting the abnormal state to the normal state can be quickly determined through the position flow algorithm model, so that the normal sintering state is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of sintering, and in particular to a sintering finish line adjustment method and system based on abnormal sintering of a tail section. Background Art

[0002] With the rapid development of modern industry, the scale of steel production is getting larger and larger, and energy consumption is also increasing. Energy conservation and environmental protection indicators are becoming more and more important factors to consider in the steel production process. In steel production, iron-containing raw ore needs to be processed by the sintering system before entering the blast furnace for smelting. That is, various powdered iron-containing raw materials are mixed with appropriate amounts of fuel (coal powder, coke powder) and flux, and appropriate amounts of water. After mixing and balling, they are placed on the sintering trolley for roasting, so that a series of physical and chemical changes occur, forming sintered ore that is easy to smelt. This process is called sintering.

[0003] The sintering end point is an important process parameter that reflects the sintering quality, output and cost. The sintering end point can indicate the end point where the material layer on the sintering trolley is roasted, that is, the sintering end position. Controlling the sintering end point at the expected sintering end point position is the key to improving the yield and making full use of the sintering area. If the actual sintering end point is earlier than the expected sintering end point position, it means that there is overburning, and the production capacity of the sintering machine (for example, the sintering area corresponding to the next few fans starting from the actual combustion end point) is not fully utilized, resulting in a reduction in the output / capacity of the sintered ore; if the actual sintering end point lags behind the expected sintering end point position, it means that the mixed material on the sintering trolley has been run to the tail of the machine for unloading before it has time to be completely roasted. At this time, there is still a lot of raw material between the combustion zone corresponding to the actual sintering end point and the bottom material layer, resulting in underburning, which ultimately affects the quality of the sintered ore.

[0004] Prior art Some sintering plants in China have begun to use gas injection technology to improve the sintering end point, that is, injecting gas during the sintering process to replace carbon with gas to participate in the sintering process. Obviously, after the gas participates in the sintering process, it will affect the vertical combustion speed and thus affect the sintering end point. However, the prior art currently does not have a control method to adjust the sintering end point by adjusting the gas, especially no specific adjustment method.

[0005] In view of this, it is necessary to propose a sintering finish line adjustment method and system based on abnormal sintering of the tail section to solve or at least alleviate the above defects. Summary of the invention

[0006] The main purpose of the present invention is to provide a sintering end point line adjustment method and system based on abnormal sintering of the tail section, so as to solve the problem that there is currently no specific quantitative control method for adjusting the sintering end point by adjusting the fuel gas in the prior art, resulting in low adjustment efficiency.

[0007] To achieve the above object, the present invention provides a sintering finish line adjustment method based on abnormal sintering of the tail section, comprising the steps of:

[0008] S1, obtaining a visible light imaging image of the current sintering machine tail section, and judging whether the current state is an abnormal sintering state according to the visible light imaging image; wherein the visible light imaging image is obtained by a visible light imaging device, and the visible light imaging device comprises an inclination sensor for detecting the inclination angle of the sintering trolley at the sintering machine tail wheel and a visible light imaging device for photographing the visible light imaging image of the sintering machine tail section; the inclination sensor is signal-interlocked with the visible light imaging device;

[0009] S2, when the current sintering state is an abnormal sintering state, according to the expected sintering end line and the pre-established position flow algorithm model, the actual sintering end line in the current state is determined to be adjusted to the first gas injection flow calculation value corresponding to the expected sintering end line; wherein the position flow algorithm model includes a mapping relationship between the gas injection flow and the sintering end line;

[0010] S3, when the first gas injection flow rate calculation value is within the effective flow rate adjustment range, adjusting the gas injection regulating valve to adjust the current gas injection flow rate to the first gas injection flow rate calculation value.

[0011] Preferably, the step S1 specifically comprises the steps of:

[0012] S11, judging whether there is a highlighted burning zone area in the visible light imaging image according to the visible light imaging image; when there is a highlighted burning zone area in the visible light imaging image, executing steps S12 to S13; when there is no highlighted burning zone area in the visible light imaging image, determining that the current state is an over-burned sintering state, and entering step S2;

[0013] S12, obtaining the current calculated combustion zone centerline according to the highlighted combustion zone area; wherein the current calculated combustion zone centerline is parallel to the top surface of the bottom material of the trolley;

[0014] S13, determine whether the vertical deviation distance between the current calculated combustion zone centerline and the ideal combustion zone centerline is greater than a preset threshold; when the vertical deviation distance is greater than the preset threshold, determine that the current state is an under-sintering state, and enter step S2; wherein, the ideal combustion zone centerline is the boundary line between the bottom surface of the sintered mixture and the bottom material of the trolley.

[0015] Preferably, after the step S13 of "determining whether the vertical deviation distance between the center line of the current calculated combustion zone and the center line of the ideal combustion zone is greater than a preset threshold value", the following steps are further included:

[0016] S131, when the vertical deviation distance is less than or equal to a preset threshold, evenly dividing the visible light imaging image along the width direction of the sintering trolley into a plurality of visible light partitions;

[0017] S132, determining whether each of the visible light partitions has a corresponding sub-highlight burning zone area;

[0018] S133, counting the number of visible light subareas having the sub-highlight burning area, and determining whether the number is less than a preset number;

[0019] S134, when the number is less than the preset number, the current state is determined to be an abnormal sintering state, and the process goes to step S2; when the number is greater than or equal to the preset number, the current state is determined to be a normal sintering state, and the current state is maintained to continue production.

[0020] Preferably, the visible light imaging image is evenly divided into six visible light partitions along the width direction of the sintering trolley, and the preset number is set to three.

[0021] Preferably, after "determining whether the vertical deviation distance between the current calculated combustion zone centerline and the ideal combustion zone centerline is greater than a preset threshold value" in step S13, it also includes the following steps: when the vertical deviation distance is less than or equal to the preset threshold value, judging the current state as a normal sintering state, and maintaining the current state to continue production.

[0022] Preferably, the step S1 further includes the following steps:

[0023] When the current sintering state is a normal state, maintaining the current sintering state and continuing production;

[0024] When the current sintering state is an abnormal sintering state, an early warning instruction is sent to the target object. Preferably, the volume of the fuel gas blown into the sintering material surface is at most 0.8% of the volume of the air entering the sintering material surface.

[0025] The present invention also provides a sintering finish line adjustment system based on abnormal sintering of the tail section, comprising a sintering machine body, a gas injection device, a visible light imaging device and a control system, wherein the sintering machine body comprises a material distribution area, an ignition furnace area and a holding furnace area, a gas injection area is provided downstream of the holding furnace area, and the gas injection device is provided in the gas injection area, wherein:

[0026] The gas injection device comprises a gas injection main pipe and a plurality of gas injection branch pipes arranged in parallel along the width direction of the sintering trolley; the gas injection main pipe is provided with the gas regulating valve; each of the gas injection branch pipes is connected to the gas injection main pipe, and a plurality of fuel nozzles for injecting gas toward the top surface of the sintering material layer are installed at the bottom of each gas injection branch pipe;

[0027] The visible light imaging device comprises an inclination sensor for detecting the inclination angle of the sintering trolley at the tail wheel of the sintering machine and a visible light imaging device for photographing a visible light imaging image of the tail section of the sintering machine; the inclination sensor is signal-linked with the visible light imaging device;

[0028] The gas injection device and the visible light imaging device are both connected to the control system, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the sintering finish line adjustment method based on abnormal sintering of the tail section are implemented as described above.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The present invention provides a sintering end line adjustment method and system based on abnormal sintering of the tail section of the machine, by obtaining the visible light imaging image of the current sintering machine tail section, and judging whether the current state is an abnormal sintering state according to the visible light imaging image, when the current sintering state is an abnormal sintering state, according to the expected sintering end line and the pre-established position flow algorithm model, the actual sintering end line in the current state is adjusted to the first gas injection flow calculation value corresponding to the expected sintering end line, and when the first gas injection flow calculation value is within the effective flow adjustment range, the gas injection regulating valve is adjusted to adjust the current gas injection flow to the first gas injection flow calculation value. The present application can use the visible light image to determine that the current state is an abnormal sintering state. The advantages of visible light are intuitive, clear, and easy to detect, analyze and interpret. After determining that it is an abnormal sintering state, the position flow algorithm model is used to quickly determine the flow adjustment value corresponding to adjusting the abnormal state to the normal state, thereby ensuring the normal sintering state.

[0031] In addition, the present invention adjusts the sintering end point position through gas injection, and there is no need to frequently adjust the sintering machine speed or material layer thickness or fan air volume, which can ensure that the sintering system as a whole is in a stable production state. As long as the stability of the fuel is guaranteed, the stability of the sintering working state can be guaranteed, which is more in line with the needs of actual production. In addition, by replacing carbon with gas, it has the effect of energy saving and emission reduction, and is more environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0033] Figure 1 It is a process flow chart of a sintering system in the prior art;

[0034] Figure 2 It is a schematic diagram of the sintered ore formation process in the prior art;

[0035] Figure 3 It is one of the cross-sectional schematic diagrams of the sintering ore formation process in the prior art;

[0036] Figure 4 The second schematic cross-sectional view of the sintering ore formation process in the prior art;

[0037] Figure 5 A schematic diagram of sintering cross-section formation and imaging in one embodiment of the present invention;

[0038] Figure 6 A side view of a schematic diagram of the overall structure of an embodiment of the present invention;

[0039] Figure 7 A top view of a schematic diagram of the overall structure of an embodiment of the present invention;

[0040] Figure 8 A schematic diagram of the formation of gas injection sintered ore in one embodiment of the present invention;

[0041] Fig. 9 is a schematic diagram of an actual sintering section of an ideal sintering section of the present invention;

[0042] Fig.10 Schematic diagram of visible light imaging of an actual sintered cross section of an ideal sintered cross section of the present invention;

[0043] Fig.11 is a schematic diagram of visible light imaging of an actual sintered cross section in one embodiment of the present invention;

[0044] Fig.12 A schematic diagram of an actual sintering cross section in one embodiment of the present invention;

[0045] Fig.13 is a schematic diagram of secondary image processing in one embodiment of the present invention;

[0046] Fig.14 is a schematic diagram of a flow chart in one embodiment of the present invention;

[0047] Fig.15 This is a flow chart of the specific steps included in step S1 in one embodiment of the present invention;

[0048] Fig.16 This is a flowchart diagram of the steps included after "determining whether the vertical deviation distance between the current calculated combustion zone centerline and the ideal combustion zone centerline is greater than a preset threshold" in step S13 in one embodiment of the present invention.

[0049] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings in conjunction with the embodiments. DETAILED DESCRIPTION

[0050] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0051] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0053] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0054] In order to enable those skilled in the art to fully understand the technical solution of this application, it should be known that the sintering system mainly includes a sintering machine trolley, a mixer, a main exhaust fan, an annular cooler and other equipment. Figure 1As shown: various raw materials are proportioned in the batching room to form a mixture. After the mixture enters the mixer for mixing and balling, it is evenly spread on the sintering machine trolley through the round roller feeder and the nine-roller distributor to form a sintering mixture layer. The ignition fan and the ignition fan start the ignition furnace, and the sintering mixture on the top layer of the sintering machine trolley is ignited in the ignition furnace. The ignited combustion zone begins to move from top to bottom, and the mixture passing through the combustion zone is roasted into sintered ore. This is the sintering process. The sintered ore obtained after sintering is crushed by a single roller crusher and then cooled in an annular cooler. Finally, it is sent to the blast furnace or finished ore bin after screening and granulation. Among them, the oxygen required for the sintering process is provided by the main exhaust fan. A number of vertically arranged bellows are arranged under the sintering machine trolley. Below the bellows is a horizontally placed large flue (or flue), which is connected to the main exhaust fan. The negative pressure wind generated by the main exhaust fan through the large flue and the bellows passes through the trolley to provide combustion-supporting air for the sintering process.

[0055] Please refer to Figure 2-4 During the sintering process, the ignited combustion zone moves from top to bottom, and the moving speed of the combustion zone is the vertical sintering speed. The sintering machine trolley moves from the head to the tail of the sintering machine, and the moving speed of the sintering machine trolley is the sintering machine speed. When the combustion zone moves to the bottom of the sintering machine trolley mixture, the corresponding position of the sintering machine trolley relative to the sintering machine head is the sintering end point. Figure 2 As shown in the figure, with the movement of the sintering machine trolley, the combustion zone gradually moves downward, and the mixed material passing through the combustion zone is roasted into sintered ore; Figure 3 As shown in the figure, during the sintering process, the materials in the sintering machine car can be divided into a bottom material layer, a mixed material layer, a combustion zone layer and a sintering ore layer from bottom to top. Figure 4 As shown, when the combustion zone moves to the bed material layer, the materials in the sintering machine trolley have all been roasted into sintered ore. At this time, the corresponding position is the sintering end position, which is generally represented by the bellows number. Optionally, the combustion zone layer has a certain thickness, and the sintering end position can be understood as the bottom of the combustion zone just touching the bed material layer. When the sintering end position is controlled at the second to last bellows or the first to last bellows, no raw meal will be produced, the fuel utilization rate is high, the sintering efficiency is high, and the quality of the sintered ore is good.

[0056] In one embodiment of the present invention, the sintering end position is controlled to be the target sintering end position when the position of the second to last bellows or the first to last bellows is set. Figure 6 As shown, the speed at which the combustion zone moves downward is called the sintering speed, which is represented by LV, in millimeters.min-1; the thickness of the material layer on the sintering machine is represented by H, in millimeters; there is a base material under the sintering mixture, which is a finished sintered ore of a certain particle size, and its thickness can be represented by PH, in millimeters; in the process of stable sintering production, the sintering speed is considered to be a constant value. After the sintered ore passes through the ignition furnace and starts the sintering process, its sintering time ST (in min) is

[0057] ST = (H-PH) / LV (1)

[0058] Controlling the sintering end point to the target sintering end point position is an important means of sintering control. During the sintering process, after the mixed material is laid on the sintering machine trolley, controlling the sintering end point at the last bellows or the second to last bellows of the sintering machine can achieve the most reasonable use of the sintering machine area. The corresponding sintering section at this time is as follows Figure 4 As shown; that is, the ideal sintering end position can be regarded as a position point within a fixed distance from the ignition position of the sintering material surface; that is, the moving distance S of the rear car after the ignition of the sintering material surface has an optimal value S0, and the position corresponding to S0 is the target sintering end position.

[0059] like Figure 2 As shown in the figure, within the sintering time ST, the relationship between the sintering machine trolley moving distance S (unit: m), the sintering machine trolley speed SV (unit: m / min), and the sintering time ST is shown in formula 2:

[0060] S=ST*SV (2)

[0061] Available

[0062]

[0063] In summary, the existing technologies for adjusting the sintering end point can be divided into three categories: the existing methods for adjusting the sintering end point are relatively simple. The first is to adjust the sintering end point by controlling the speed of the sintering trolley; the second is to adjust the sintering end point by controlling the sintering main exhaust fan system (negative pressure, air volume); the third is to adjust the sintering end point by controlling the thickness of the sintering material layer. There is a technical problem that these adjustment methods are too dependent on the main structure of the sintering system. This dependence is reflected in, for example, that adjusting the machine speed will cause frequent changes in the equipment state and the equipment will be in an unstable working state. If the thickness of the material layer is adjusted frequently, it will cause fluctuations in output / capacity. If the fan air volume is adjusted frequently, it will also cause the equipment to be in an unstable working state, increasing the technical problems of equipment wear and energy consumption.

[0064] Please refer to Figure 5-13 Through the study of sintering technology, it is found that during the sintering process, injecting gas into the sintering material and using gas instead of carbon to participate in the sintering process can affect the vertical combustion speed, thereby affecting the sintering end position. Specifically, after the gas is sprayed onto the sintering material surface, it enters the sintering material layer with the air. When the gas reaches the temperature area above the solid combustion zone that is higher than the gas combustion point, the gas is ignited to form a gas combustion zone suspended above the solid combustion zone; the gas combustion zone will burn downward synchronously with the solid combustion zone, and the heat released by the gas combustion zone will be quickly conducted downward and superimposed on the solid combustion zone, thereby accelerating the combustion speed of the solid combustion zone and increasing the combustion temperature of the solid combustion zone.

[0065] Please refer to Figure 11-13 Through the study of sintering technology, in the process of sintering ore generation, because the air permeability of sintering ore at various places on the sintering machine trolley is not exactly the same, the sintering end point in actual production will not be an ideal straight line (ideal sintering end line), and the bright line reflected in visible light is not an ideal straight line. In actual production, those in front of the ideal sintering end line can be considered as premature sintering, and the production capacity of the sintering machine is not fully utilized, resulting in a decrease in the output of sintered ore. Those behind the ideal sintering end line can be considered as over-sintering, which ultimately affects the quality of sintered ore.

[0066] Please refer to Figure 5-7 The present invention provides a sintering end line adjustment system based on abnormal sintering of the tail section, comprising a sintering machine body, a gas injection device, a visible light imaging device and a control system. The sintering machine body comprises a material distribution area, an ignition furnace area and a holding furnace area. A gas injection area is provided downstream of the holding furnace area. The gas injection device is provided in the gas injection area.

[0067] The gas injection device comprises a gas injection main pipe and a plurality of gas injection branch pipes arranged in parallel along the width direction of the sintering trolley; the gas injection main pipe is provided with the gas regulating valve; each of the gas injection branch pipes is connected to the gas injection main pipe, and a plurality of fuel nozzles for injecting gas toward the top surface of the sintering material layer are installed at the bottom of each gas injection branch pipe;

[0068] The visible light imaging device comprises an inclination sensor for detecting the inclination angle of the sintering trolley at the tail wheel of the sintering machine and a visible light imaging device for photographing a visible light imaging image of the tail section of the sintering machine; the inclination sensor is signal-linked with the visible light imaging device;

[0069] The gas injection device and the visible light imaging device are both connected to the control system, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the sintering finish line adjustment method based on abnormal sintering of the tail section are implemented as described below.

[0070] Optionally, the gas injection zone is arranged adjacent to the insulation furnace zone, a gas injection device is provided in the gas injection zone, and a gas injection branch pipe is arranged opposite to the trolley track and is used to spray gas to the trolley on the trolley track passing through the gas injection zone.

[0071] In addition, the gas injection main pipe is connected to an external fuel storage device. As long as a stable supply of fuel is ensured, a stable sintering working state can be guaranteed.

[0072] It should be noted that the tilt sensor is interlocked with the visible light imaging device signal. The sintering machine trolley carries sintered ore and moves forward under the drive of the sintering head and tail wheels. At the sintering tail wheels, the sintering machine trolley begins to tilt, and the continuous sintering material surface begins to break from the tilt of the trolley. When the tail wheel drives the trolley to reach the tilt angle A, the tilt sensor can capture this angle, and the whole piece of sintered ore on the tilting trolley slides off the trolley. The sintered ore section of the adjacent sintering machine trolley can be fully displayed in front of the camera. The schematic diagram of the sintering section formation and imaging can be referred to in the attached figure. Figure 9-12 As shown:

[0073] Therefore, an inclination sensor can be installed on the tail wheel of the sintering machine to track the inclination angle A of the sintering machine trolley. When the inclination angle A of the sintering machine trolley is reached, the visible light camera takes a picture of the sintering machine tail section, thereby obtaining a visible light imaging image of the sintering machine tail section. In other embodiments, those skilled in the art can also choose other technical means, as long as they can capture the unloading section between two adjacent sintering machine trolleys.

[0074] In a preferred embodiment, the plurality of gas injection branch pipes are evenly arranged along the width direction of the sintering machine trolley, and the plurality of burner nozzles of each gas injection branch pipe are evenly arranged along the length direction of the gas injection branch pipe. By evenly arranging, the effect of the entire sintering end point controlled by gas injection is more accurate (each partition can be adjusted by individually controlling each partition). In other embodiments, those skilled in the art can also adaptively adjust the spacing distance between the plurality of gas injection pipes, or adaptively adjust the spacing distance between the plurality of burner nozzles on each gas injection branch pipe. In addition, by evenly arranging, it is convenient for each sub-partition (one gas injection branch pipe can be set to correspond to one sub-partition), and targeted adjustment of the sub-partition can be achieved, thereby adjusting the uniformity of the sintered ore.

[0075] Please see attached Figures 14 to 16 The present invention provides a sintering finish line adjustment method based on abnormal sintering of the tail section, comprising the steps of:

[0076] S1, obtain the visible light imaging image of the current sintering machine tail section, and judge whether the current state is an abnormal sintering state according to the visible light imaging image; wherein, the visible light imaging image is obtained by a visible light imaging device, and the visible light imaging device includes an inclination sensor for detecting the inclination angle of the sintering trolley at the sintering machine tail wheel and a visible light imaging device for photographing the visible light imaging image of the sintering machine tail section; the inclination sensor is signal-interlocked with the visible light imaging device; it should be noted that the visible light imaging image of the present application can be obtained by manual photography, or by a visible light imaging device, as long as the visible light imaging image of the current sintering machine tail section can be obtained. The visible light imaging device can be a camera shooting device, or a video monitoring device, preferably a camera shooting device, and then the acquired image information is processed as follows:

[0077] It should be noted that the brightness of visible light is positively correlated with temperature. Therefore, the pixels in the visible light imaging image whose brightness is higher than the set value (the set value can be set to the brightness value corresponding to the temperature range of the combustion zone) can be set to highlighted, and the pixels in the visible light imaging image whose brightness is lower than or equal to the set value can be set to black, thereby obtaining a visible light imaging image.

[0078] S2, when the current sintering state is an abnormal sintering state, the actual sintering end line in the current state is determined to be adjusted to the first gas injection flow calculation value corresponding to the expected sintering end line according to the expected sintering end line and the pre-established position flow algorithm model; wherein the position flow algorithm model includes the mapping relationship between the gas injection flow and the sintering end line; it is worth noting that the position flow algorithm model of the present application is obtained through pre-theoretical derivation and verified through specific examples (specific examples below), and has high calculation accuracy. Therefore, when the expected sintering end line is known, the corresponding first gas injection flow calculation value can be calculated, and the gas injection flow in the current state is adjusted to this value, so that the corresponding actual sintering end line can be adjusted to the expected sintering end line position.

[0079] Furthermore, the “location flow algorithm model” in step S2 is specifically:

[0080]

[0081] Wherein, S is the sintering end line, Q is the theoretical calculated value of the gas injection flow rate corresponding to the sintering end line S; H is the total thickness of the material layer on the sintering trolley, PH is the thickness of the bottom material layer, SV is the speed of the sintering trolley, c is the thickness of the solid combustion zone, k1 is the heat transfer coefficient, h is the gas combustion heat, t is the duration of gas injection, m is the unit sintering machine material amount, z is the material layer thickness below the gas combustion zone, and Cp is the average specific heat capacity of the sintering material.

[0082] Specifically, in order to further illustrate the location flow algorithm model and facilitate those skilled in the art to understand the location flow algorithm model of the present application, the derivation process of the model is now specifically described:

[0083] First, according to the heat balance formula, the heat release power of gas fuel burning in the material layer can be calculated by formula 4:

[0084] P1=Q*h Formula 4

[0085] Where: P1: fuel heating power, unit W; Q: gas fuel flow, unit Nm 3 / s; h: Combustion heat of gas fuel, unit J / Nm 3 ;

[0086] It can be understood that part of the heat released by the combustion of the gas fuel will be directly transferred to the solid combustion zone with a thickness of c located in the lower layer, so that its initial temperature will be increased by ΔT compared with the conventional sintering temperature; part of the heat will pass through the solid combustion zone in the form of flue gas sensible enthalpy, continue to be transferred downward and add to the materials under the solid combustion zone; among them, the initial temperature increase ΔT of the material to be ignited near the solid combustion zone can be calculated by Formula 5 and Formula 6:

[0087] Secondly, the heat generated by combustion is carried away by the flue gas, heating the material under the combustion zone. After the flue gas passes through the material and solid combustion zone, the flue gas temperature will rise. By comparing the flue gas temperature of the bellows before gas injection and the flue gas temperature of the bellows after gas injection, the heat carried away by the flue gas and the heat left in the material can be calculated.

[0088] The heat remaining in the material heats all the materials below the gas combustion zone. The ratio of the heat remaining in the material to the heat taken away by the flue gas can be calculated, and the temperature rise of the material can be calculated. The gas combustion zone gradually moves downward, that is, the solid material heated by the heat of the gas combustion zone gradually decreases as the sintering machine moves forward. The flue gas passes through the sintering ore layer, the gas combustion zone, the sintering ore layer between the gas-solid combustion zone, the solid combustion zone, and the mixed material layer; the flue gas is heated by the sintering ore layer and gradually increases in temperature; after passing through the gas combustion zone and the solid combustion zone, the temperature increases and heats the lower layer materials. Because the gas combustion zone and the solid combustion zone gradually move downward, the heated lower layer materials gradually decrease;

[0089] According to the heat balance formula P2=k1*P1, (Formula 5) the heat P2 directly transferred from the gas combustion to the material below the gas combustion zone is determined; wherein P2 is the heat directly transferred from the gas combustion to the material, in units of W;

[0090] According to the formula Determine the initial temperature increase ΔT of the material to be ignited near the solid combustion zone caused by gas combustion;

[0091] Where: P2: heat directly transferred to the material by gas combustion, unit W; k1: transfer coefficient, dimensionless; (slightly different for different sintering machines, it can be regarded as a constant under the stable working condition of the same sintering machine); ΔT: initial temperature increase of solid combustion zone material brought by gas fuel, unit K; m is the material amount per unit sintering machine, unit kg; z: thickness of the material layer under the gas combustion zone, unit m; H: total thickness of the material layer, unit m; Cp: average specific heat capacity of sintering material, unit J / (kg*K); t: duration of gas injection, unit s;

[0092] The specific derivation process of formula 6 is as follows:

[0093] From the derivation of formula 5, it can be seen that the heat of P2 is transferred to the material layer below the combustion zone, and the thickness of the material layer below the combustion zone is Z; the total thickness of the material layer is H;

[0094] During the gas injection period, the materials above the gas combustion zone will not be heated by the heat provided by the gas combustion zone, and the amount of heated materials below the gas combustion zone is m*(z / H), and the duration is t;

[0095] Formula 6a can be derived

[0096]

[0097] T2: Initial material temperature; T1: Temperature of the material after being heated by the gas combustion zone

[0098] ΔT=T1-T2

[0099] Substituting formula 4 and 6a into formula 6, we can obtain:

[0100]

[0101] In formula 7, the transfer coefficient k1, the combustion heat of gas fuel h, and the average specific heat capacity Cp of sintering materials can be regarded as constants. Under the condition of stable production of the sintering machine, the total thickness of the material layer H, the material amount per unit sintering machine m, and the gas injection time t can be regarded as constants. The thickness of the material layer z under the gas combustion zone gradually decreases as the sintering machine moves forward. In the gas injection range, the average value can be taken as 0.75*H~0.85*H. The coefficient K1 can be obtained as shown in formula 8:

[0102] According to the formula P1 = Q*h, the formula P2 = k1*P1 and the formula Determine

[0103] Substituting formula 8 into formula 7, we get:

[0104] ΔT=K1*Q Formula 9

[0105] It can be seen from Formula 9 that when the sintering machine speed is stable, the initial temperature rise value of the solid combustion zone material under the gas combustion zone and the gas flow rate can be approximately regarded as a linear relationship.

[0106] It should be noted that the combustion of sintered solid fuel mainly includes four processes: 1. Preheating of carbon powder; 2. Volatile analysis; 3. Combustion of volatiles; 4. Combustion of residual carbon. The latter three processes involving complex heat transfer, mass transfer and chemical reaction coupling can be collectively referred to as the full combustion process. The total time tt of solid fuel combustion can be approximately regarded as the sum of the time t1 for the carbon powder residual heat to reach the ignition point temperature and the time t2 for the carbon powder to be fully burned. The effect of gas injection on the combustion rate of solid fuel is mainly manifested in increasing the temperature of the starting reactants, thereby reducing the preheating time t1. After the solid fuel starts to burn, the full combustion time t2 remains unchanged.

[0107] Before and after gas injection, the heat transfer coefficient between the sintering material layer and the high-temperature gas can be approximately considered unchanged. Therefore, the preheating time t1 can be calculated by formula 10:

[0108]

[0109] Where: Tc: ignition point temperature of carbon powder, unit K; T0: initial temperature of combustion zone material before injection, unit K; ΔT: initial temperature increase of combustion zone material caused by gas injection, unit K; V: material layer heating rate, unit K / s;

[0110] Therefore, the total time tt of solid fuel combustion can be calculated using formula 11:

[0111]

[0112] Obviously, the fuel thickness in the solid combustion zone divided by the total time of solid fuel combustion is the combustion speed of the solid combustion zone moving downward, and formula 12 can be obtained:

[0113]

[0114] Substituting Formula 9 into Formula 11, we get:

[0115]

[0116] Typical values ​​of relevant parameters are shown in Table 1

[0117] Table 1: Typical values ​​of relevant parameters

[0118]

[0119]

[0120] Substituting typical values ​​into formula 13, we get:

[0121]

[0122] Right now

[0123]

[0124] Substituting formula 12 into formula 10, we get:

[0125]

[0126] Substituting Formula 15 into Formula 3, we get:

[0127]

[0128] According to formula 16, the location flow algorithm model of this application is obtained:

[0129]

[0130] Here are some examples:

[0131] The material layer thickness of a sintering machine is H = 0.7m, the bottom material layer thickness is PH = 0.1m, the unit sintering machine material quantity is 250kg, the sintering trolley speed is SV = 0.035m / s, the solid combustion zone thickness is c = 0.03m, the bottom material layer thickness is PH = 0.1m, the average specific heat capacity of the sintering material is Cp = 1600J / (kg*K), the gas injection time is 500s, the transfer coefficient is k1 = 0.35, and the unit gas combustion heat is h = 30000000J / Nm 3 ;

[0132] When the gas injection flow rate is 0Nm 3 / s, we can calculate:

[0133]

[0134] The total length of the sintering machine is 90 meters, the length of a single wind box is 4 meters, the length from the material distribution to the ignition position is 10 meters, the length from the starting position of the solid combustion zone to the gas injection position is 10 meters, and the length of the gas injection section is 20 meters;

[0135] Without considering gas injection, the ideal sintering end point is at the tail of the sintering machine, that is, 90-14=76 meters; if the combustion zone thickness is considered to be 25mm and the material layer is considered to be 800mm, the calculated position is 74.06m; matching the actual situation, it can be seen that the above formula 16 is accurate.

[0136] As another example, when the gas injection flow rate is 0.006 Nm 3 / s, we can calculate:

[0137]

[0138] As another example, when the gas injection flow rate is 0.005 Nm 3 / s, we can calculate:

[0139]

[0140] The accuracy of Formula 16 can be verified through the above specific examples, which also illustrates that the position flow algorithm model of the present application has high accuracy and can be used to guide the adjustment of the gas injection flow rate.

[0141] S3, when the first gas injection flow rate calculation value is within the effective flow rate adjustment range, adjust the gas injection regulating valve to adjust the current gas injection flow rate to the first gas injection flow rate calculation value. Specifically, in practical applications, considering the safety of gas and other issues, the maximum volume fraction of gas injection is 0.8%, that is, gas injection has an effective injection flow rate range. It can be understood that if the current gas injection flow rate is too large, there will be a gas safety problem. In a specific example, the effective flow rate adjustment range is set at 0.005~0.1Nm 3 In other words, when the calculated value of the first fuel gas injection flow rate is between 0.005 and 0.1 Nm 3 / s, the gas injection regulating valve is adjusted to adjust the current gas injection flow rate to the first gas injection flow rate calculation value, and the corresponding actual sintering end line can be adjusted to the expected sintering end line position. If the first gas injection flow rate calculation value is not within the effective flow rate adjustment range, an alarm reminder can be issued to the target object so that the abnormal situation can be handled in time.

[0142] As a preferred embodiment of the present invention, step S1 specifically includes the following steps:

[0143] S11, judging whether there is a highlighted burning zone area in the visible light imaging image according to the visible light imaging image; when there is a highlighted burning zone area in the visible light imaging image, executing steps S12 to S13; when there is no highlighted burning zone area in the visible light imaging image, determining that the current state is an over-burned sintering state, and entering step S2;

[0144] S12, obtaining the current calculated combustion zone centerline according to the highlighted combustion zone area; wherein the current calculated combustion zone centerline is parallel to the top surface of the bottom material of the trolley; in order to facilitate quantification of the distance between the highlighted combustion zone area and the current calculated combustion zone centerline, the highlighted combustion zone area is used to obtain the current calculated combustion zone centerline that can represent the position of the highlighted combustion zone area. It can be understood that the method of obtaining the current calculated combustion zone centerline from the highlighted combustion zone area can be a rough calculation or a more accurate calculation method. In order to facilitate quantification of the distance between the highlighted combustion zone area and the top surface of the bottom material of the sintering trolley, the current calculated combustion zone centerline of the present application is parallel to the top surface of the bottom material of the sintering trolley, that is, a horizontal line parallel to the top surface of the bottom material of the sintering trolley.

[0145] S13, determine whether the vertical deviation distance between the current calculated combustion zone centerline and the ideal combustion zone centerline is greater than a preset threshold; when the vertical deviation distance is greater than the preset threshold, determine that the current state is an under-sintering state, and enter step S2; wherein, the ideal combustion zone centerline is the boundary line between the bottom surface of the sintered mixture and the bottom material of the trolley.

[0146] It is worth noting for those skilled in the art that the sintered ore formation process is a process in which the sintering combustion zone gradually moves downward. The combustion temperature of the sintering combustion zone is about 1250°C. The sintering mixture is mixed with various ingredients such as fuel, flux, iron ore, etc. After the sintering material surface is ignited at the ignition furnace at the head of the sintering machine, a combustion zone with a thickness of about 20 to 30 mm is formed. Various mixtures in the combustion zone are formed after high-temperature roasting to form sintered ore. After the combustion zone gradually moves downward to the bottom of the sintering trolley to lay the bottom material layer, the combustion zone will no longer move downward, and the fuel in the area passed by the combustion zone has been burned; in the process of the combustion zone gradually moving downward, the sintering trolley is also moving toward the tail of the machine. Under ideal conditions, when the sintering trolley moves to the appropriate area at the tail of the sintering machine, the combustion zone reaches the bottom material layer. At this time, the utilization rate of the sintering area is the highest, which is most beneficial to production. It can be known that the preset threshold in this embodiment is set to ensure that the sintering state is as close to the ideal state as possible. Therefore, when the vertical deviation distance between the center line of the current calculation combustion zone and the center line of the ideal combustion zone is greater than the preset threshold, it means that after the sintering trolley moves to the set position at the tail of the sintering machine, the combustion zone is still a certain distance away from the bottom material layer, indicating that there are still many raw ores between the current calculation combustion zone and the center line of the ideal combustion zone that have not been effectively sintered, that is, the current actual sintering end line lags behind the target sintering end line, and this state should be regulated at this time. On the contrary, when the vertical deviation distance is less than or equal to the preset threshold, it means that the sintering mixture between the current calculation combustion zone and the center line of the ideal combustion zone is less (within the acceptable range in this field) or all of them are effectively sintered, that is, it is determined that the current actual sintering end point is within the tolerance range of the target sintering end point, and the current state is maintained to continue production.

[0147] As a preferred embodiment, after "determining whether the vertical deviation distance between the center line of the current calculated combustion zone and the center line of the ideal combustion zone is greater than a preset threshold" in step S13, the following steps are also included:

[0148] S131, when the vertical deviation distance is less than or equal to a preset threshold, evenly dividing the visible light imaging image along the width direction of the sintering trolley into a plurality of visible light partitions;

[0149] S132, determining whether each of the visible light partitions has a corresponding sub-highlight burning zone area;

[0150] S133, counting the number of visible light subareas having the sub-highlight burning area, and determining whether the number is less than a preset number;

[0151] S134, when the number is less than the preset number, the current state is determined to be an abnormal sintering state, and the process goes to step S2; when the number is greater than or equal to the preset number, the current state is determined to be a normal sintering state, and the current state is maintained to continue production.

[0152] It should be noted that when the vertical deviation distance is less than or equal to the preset threshold, the sintering state may still be an abnormal state (for example, uneven cross-section along the sintering trolley) or it may be a normal state. This implementation determines whether each of the visible light partitions has a corresponding sub-highlight combustion zone area, counts the number of visible light partitions with the sub-highlight combustion area, and determines whether the number is less than the preset number. When the number is less than the preset number, it means that the visible light partitions are relatively scattered and uneven, thereby affecting the quality of the sintered ore, and the current state is determined to be an abnormal sintering state. When the number is greater than or equal to the preset number, it is determined that the visible light partitions are relatively uniform, and the current state is determined to be a normal sintering state, and the current state is maintained to continue production.

[0153] As a specific example, the visible light imaging image is evenly divided into six visible light partitions along the width direction of the sintering trolley, and the preset number is set to three. In other embodiments, those skilled in the art may also set the preset number to other numbers. In addition, it should be noted that the more detailed the visible light partitions are, the more helpful it is to analyze the cross-sectional uniformity of the sintered ore.

[0154] Furthermore, after "determining whether the vertical deviation distance between the current calculated combustion zone centerline and the ideal combustion zone centerline is greater than a preset threshold value" in step S13, the step of: when the vertical deviation distance is less than or equal to the preset threshold value, determining that the current state is a normal sintering state, and maintaining the current state to continue production.

[0155] As another preferred embodiment, the step S1 further includes the following steps:

[0156] When the current sintering state is a normal state, maintaining the current sintering state and continuing production;

[0157] When the current sintering state is an abnormal sintering state, an early warning reminder instruction is sent to the target object. The preset alarm instruction includes: one or more of issuing a prompt voice instruction, issuing an alarm instruction, sending information to a server or a target account, and cutting off the power of the sintering machine system.

[0158] Preferably, the volume of the fuel gas blown into the sintering material surface is at most 0.8% of the volume of the air entering the sintering material surface.

[0159] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A sintering finish line adjustment method based on abnormal sintering of the tail section, characterized in that: Includes steps: S1, obtaining a visible light imaging image of the current sintering machine tail section, and judging whether the current state is an abnormal sintering state according to the visible light imaging image; wherein the visible light imaging image is obtained by a visible light imaging device, and the visible light imaging device comprises an inclination sensor for detecting the inclination angle of the sintering trolley at the sintering machine tail wheel and a visible light imaging device for photographing the visible light imaging image of the sintering machine tail section; the inclination sensor is signal-interlocked with the visible light imaging device; S2, when the current sintering state is an abnormal sintering state, according to the expected sintering end line and the pre-established position flow algorithm model, the actual sintering end line in the current state is determined to be adjusted to the first gas injection flow calculation value corresponding to the expected sintering end line; wherein the position flow algorithm model includes a mapping relationship between the gas injection flow and the sintering end line; S3, when the first gas injection flow rate calculation value is within the effective flow rate adjustment range, adjusting the gas injection regulating valve to adjust the current gas injection flow rate to the first gas injection flow rate calculation value.

2. The sintering finish line adjustment method based on abnormal sintering of the tail section according to claim 1 is characterized in that: The step S1 specifically includes the following steps: S11, judging whether there is a highlighted burning zone area in the visible light imaging image according to the visible light imaging image; when there is a highlighted burning zone area in the visible light imaging image, executing steps S12 to S13; when there is no highlighted burning zone area in the visible light imaging image, determining that the current state is an over-burned sintering state, and entering step S2; S12, obtaining the current calculated combustion zone centerline according to the highlighted combustion zone area; wherein the current calculated combustion zone centerline is parallel to the top surface of the bottom material of the trolley; S13, determine whether the vertical deviation distance between the current calculated combustion zone centerline and the ideal combustion zone centerline is greater than a preset threshold; when the vertical deviation distance is greater than the preset threshold, determine that the current state is an under-sintering state, and enter step S2; wherein, the ideal combustion zone centerline is the boundary line between the bottom surface of the sintered mixture and the bottom material of the trolley.

3. The sintering finish line adjustment method based on abnormal sintering of the tail section according to claim 2 is characterized in that: After "determining whether the vertical deviation distance between the center line of the current calculated combustion zone and the center line of the ideal combustion zone is greater than a preset threshold" in step S13, the following steps are also included: S131, when the vertical deviation distance is less than or equal to a preset threshold, evenly dividing the visible light imaging image along the width direction of the sintering trolley into a plurality of visible light partitions; S132, respectively determining whether each of the visible light partitions has a corresponding sub-highlight burning zone area; S133, counting the number of visible light subareas having the sub-highlight burning area, and determining whether the number is less than a preset number; S134, when the number is less than the preset number, the current state is determined to be an abnormal sintering state, and the process goes to step S2; when the number is greater than or equal to the preset number, the current state is determined to be a normal sintering state, and the current state is maintained to continue production.

4. The sintering finish line adjustment method based on abnormal sintering of the tail section according to claim 3 is characterized in that: The visible light imaging image is evenly divided into six visible light partitions along the width direction of the sintering trolley, and the preset number is set to three.

5. The sintering finish line adjustment method based on abnormal sintering of the tail section according to claim 2 is characterized in that: The step S13 further includes the following steps after "determining whether the vertical deviation distance between the center line of the current calculated combustion zone and the center line of the ideal combustion zone is greater than a preset threshold value": when the vertical deviation distance is less than or equal to the preset threshold value, determining that the current state is a normal sintering state, and maintaining the current state to continue production.

6. The sintering finish line adjustment method based on abnormal sintering of the tail section according to claim 1 is characterized in that: The step S1 further includes the following steps: When the current sintering state is a normal state, maintaining the current sintering state and continuing production; When the current sintering state is an abnormal sintering state, an early warning reminder instruction is sent to the target object.

7. The sintering finish line adjustment method based on abnormal sintering of the tail section according to claim 1 is characterized in that: The volume of the fuel gas blown into the sintering material surface is at most 0.8% of the volume of the air entering the sintering material surface.

8. A sintering finish line adjustment system based on abnormal sintering of the tail section, characterized in that: The invention comprises a sintering machine body, a gas injection device, a visible light imaging device and a control system. The sintering machine body comprises a material distribution area, an ignition furnace area and a heat preservation furnace area. A gas injection area is arranged downstream of the heat preservation furnace area. The gas injection device is arranged in the gas injection area. The gas injection device comprises a gas injection main pipe and a plurality of gas injection branch pipes arranged in parallel along the width direction of the sintering trolley; the gas injection main pipe is provided with the gas regulating valve; each of the gas injection branch pipes is connected to the gas injection main pipe, and a plurality of fuel nozzles for injecting gas toward the top surface of the sintering material layer are installed at the bottom of each gas injection branch pipe; The visible light imaging device comprises an inclination sensor for detecting the inclination angle of the sintering trolley at the tail wheel of the sintering machine and a visible light imaging device for photographing a visible light imaging image of the tail section of the sintering machine; the inclination sensor is signal-linked with the visible light imaging device; The gas injection device and the visible light imaging device are both connected to the control system, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of the sintering finish line adjustment method based on abnormal sintering of the tail section as described in any one of claims 1 to 7 are implemented.

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