A sintering finish line adjustment method and system based on abnormal sintering of tail section

Abstract

The present invention provides a method and system for adjusting the sintering end line based on abnormal sintering at the tail section of the sintering machine. By obtaining a visible light imaging image of the current sintering machine tail section and judging whether the current state is an abnormal sintering state based on the visible light imaging image, when the current sintering state is an abnormal sintering state, 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 based on the expected sintering end line and a pre-established position flow algorithm model. 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 quickly determine the flow adjustment value corresponding to adjusting the abnormal state to the normal state through the position flow algorithm model when it is determined that the current state is an abnormal sintering state through the visible light image, thereby ensuring a normal sintering state.

Description

Technical Field

[0001] The present 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 growing, and energy consumption is also increasing. Energy conservation and environmental protection indicators are becoming increasingly important considerations in the steel production process. In steel production, iron-containing raw ore needs to be processed through a sintering system before entering the blast furnace for smelting. This is to process various powdered iron-containing raw materials, add appropriate amounts of fuel (coal powder, coke powder) and flux, add an appropriate amount of water, mix and pelletize, and then place them on a sintering trolley for roasting. This process causes a series of physical and chemical changes to occur, forming a 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. It indicates 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 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, 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 decrease in the sintered ore output / capacity. If the actual sintering end point lags behind the expected sintering end point, it means that the mixed material on the sintering trolley has run to the tail of the machine for unloading before it has had 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] Some sintering plants in China have begun using gas injection technology to improve the sintering endpoint. This involves injecting gas during the sintering process, replacing carbon with gas. While the addition of gas to the sintering process significantly affects the vertical combustion velocity and, consequently, the sintering endpoint, there is currently no control method, particularly a specific method, for adjusting the sintering endpoint by regulating the gas.

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

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

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

[0008] S1, obtaining a visible light imaging image of the current sintering machine tail section, and determining whether the current state is an abnormal sintering state based on 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 a tilt sensor for detecting the tilt angle of the sintering trolley on the sintering machine tail wheel and a visible light imaging device for capturing the visible light imaging image of the sintering machine tail section; the tilt sensor and the visible light imaging device are signal-linked;

[0009] S2, when the current sintering state is an abnormal sintering state, determining, based on a desired sintering end line and a pre-established position flow algorithm model, that the actual sintering end line in the current state is adjusted to a first calculated value of the gas injection flow rate corresponding to the desired sintering end line; wherein the position flow algorithm model includes a mapping relationship between the gas injection flow rate and the sintering end line;

[0010] S3: When the first gas injection flow rate calculation value is within the effective flow rate adjustment range, regulating 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 includes the steps of:

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

[0013] S12, obtaining a currently calculated combustion zone centerline based on the highlighted combustion zone area; wherein the currently calculated combustion zone centerline is parallel to the top surface of the bottom material paved on 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", 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 zones;

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

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

[0019] S134, when the number is less than the preset number, determine the current state as an abnormal sintering state and enter step S2; when the number is greater than or equal to the preset number, determine the current state as a normal sintering state, and maintain the current state 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 center line of the current calculated combustion zone and the center line of the ideal combustion zone 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.

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

[0023] When the current sintering state is normal, 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 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 at 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, and the gas injection device is provided in the gas injection area, wherein:

[0026] The gas injection device includes 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 regulating valve is installed on the gas injection main pipe; each of the gas injection branch pipes is connected to the gas injection main pipe, and a plurality of burners 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 includes 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 taking a visible light image of the cross section of the tail wheel 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 runnable 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 method and system for adjusting the sintering end line based on abnormal sintering at the tail section of the sintering machine. By obtaining a visible light imaging image of the current sintering machine tail section and judging whether the current state is an abnormal sintering state based on the visible light imaging image, when the current sintering state is an abnormal sintering state, 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 based on the expected sintering end line and a pre-established position flow algorithm model. 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 visible light images to determine that the current state is an abnormal sintering state. The advantages of visible light are that it is intuitive, clear, and easy to detect, analyze, and interpret. After determining that the sintering state is abnormal, 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 a 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 following briefly introduces the drawings required for use in the embodiments or the description of the prior art. 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 any creative work.

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

[0034] Figure 2 Schematic diagram of the sintered ore formation process in the prior art;

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

[0036] Figure 4 This is the second cross-sectional schematic diagram of the sinter formation process in the prior art;

[0037] Figure 5 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 Schematic diagram of formation of sintered ore by gas injection in one embodiment of the present invention;

[0041] Figure 9 Schematic diagram of the actual sintering section of the ideal sintering section of the present invention;

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

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

[0044] Figure 12 This is a schematic diagram of an actual sintering cross section in one embodiment of the present invention;

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

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

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

[0048] Figure 16 This is a flowchart diagram of steps including steps 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 and 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 intended to limit the present invention.

[0051] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall 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 various 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 for descriptive purposes only and should not 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" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such 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 in the figure: Various raw materials are proportioned in the batching chamber to form a mixture. The mixture enters the mixer for mixing and pelletizing. Then, it is evenly distributed on the sintering machine trolley by the circular roller feeder and the nine-roller distributor to form a sintering mixture layer. The ignition fan and the ignition fan start the ignition furnace, which ignites the sintering mixture on the top layer of the sintering machine trolley. The ignited combustion zone begins to move from top to bottom. 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 cooled in an annular cooler. Finally, it is screened and sized into whole particles before being sent to the blast furnace or finished ore bin. Among them, the oxygen required for the sintering process is provided by the main exhaust fan. A number of vertically arranged side-by-side bellows are arranged under the sintering machine trolley. Below the bellows is a horizontally placed large flue (or flue). The large flue 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 mixture on the sintering machine trolley, the corresponding position of the sintering machine trolley relative to the head of the sintering machine 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 mixture 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 the bottom material layer, the mixed material layer, the combustion zone layer and the sintered ore layer from bottom to top. Figure 4 As shown in the figure, when the combustion zone moves to the bed material layer, the materials in the sintering machine trolley have all been roasted into sintered ore. The corresponding position at this time 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 point where the bottom of the combustion zone just contacts 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 is produced, fuel utilization is high, sintering efficiency is high, and sintered ore quality 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 in the figure, the speed at which the combustion zone moves downward is called the sintering speed, which is represented by LV and is in mm.min-1. The thickness of the material layer on the sintering machine is represented by H and is in mm. There is a base material under the sintering mixture, which is a finished sintered ore of a certain particle size. The thickness can be represented by PH and is in mm. 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 the sintering process begins, 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 or second to last wind box 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 sintering material surface is ignited 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, during 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 sintering trolley speed; 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. These adjustment methods have the technical problem of being 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 equipment wear and energy consumption.

[0064] Please refer to Figure 5-13 Through the study of sintering technology, it was 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 point position. Specifically, after the gas is sprayed onto the sintering material surface, it enters the sintering material layer along with the air. When the gas reaches the temperature area above the solid combustion zone where the temperature is higher than the gas combustion point, the gas is ignited, forming 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 research on sintering technology, it has been found that during the sintering process, the permeability of sintered ore varies from place to place on the sintering machine car. Therefore, the sintering endpoint in actual production is not an ideal straight line (the ideal sintering endpoint line), and the bright line reflected in visible light is also not an ideal straight line. In actual production, sintering that is ahead of the ideal sintering endpoint line can be considered premature, and the production capacity of the sintering machine is not fully utilized, resulting in reduced sintered ore production. Sintering that is behind the ideal sintering endpoint line can be considered over-sintering, which ultimately affects the quality of the sintered ore.

[0066] Please refer to Figure 5-7 The present invention provides a sintering finish line adjustment system based on abnormal sintering at 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, and the gas injection device is provided in the gas injection area, wherein:

[0067] The gas injection device includes 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 regulating valve is installed on the gas injection main pipe; each of the gas injection branch pipes is connected to the gas injection main pipe, and a plurality of burners 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 includes 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 taking a visible light image of the cross section of the tail wheel 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 runnable 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 follows.

[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 the gas injection branch pipe is arranged opposite the trolley track and is used to inject 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 the external fuel storage device. As long as the stable supply of fuel is guaranteed, the 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 sintered 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 entire piece of sintered ore on the tilting trolley slides off the trolley. The sintered ore cross section of the adjacent sintering machine trolley can be fully displayed in front of the camera. The schematic diagram of the sintering cross section formation and imaging can be referred to in the attached figure. Figure 9-12 As shown:

[0073] Therefore, a tilt 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 sintering machine trolley reaches the inclination angle A, the visible light camera will take a picture of the cross section of the sintering machine tail, thereby obtaining a visible light image of the cross section of the sintering machine tail. In other embodiments, those skilled in the art may also use 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 uniformly arranging, the effect of the entire sintering end point controlled by gas injection is made more accurate (each partition can be adjusted by controlling it separately). In other embodiments, those skilled in the art can also adaptively adjust the spacing between the plurality of gas injection pipes, or adaptively adjust the spacing between the plurality of burner nozzles on each gas injection branch pipe. In addition, by uniformly arranging, it is convenient for each sub-partition (one gas injection branch pipe can be set to correspond to one sub-partition), and targeted adjustments can be made to the sub-partitions, thereby adjusting the uniformity of the sintered ore.

[0075] Please see the attached Figures 14-16 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 based on 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 on the sintering machine tail wheel and a visible light imaging device for shooting the visible light imaging image of the sintering machine tail section; the inclination sensor is signal-linked 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 shooting or by a visible light imaging device, as long as it is a method that can obtain the visible light imaging image of the current sintering machine tail section. 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 highlight, 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 a 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. Since the pre-established position flow algorithm model includes a mapping relationship between the gas injection flow and the sintering end line, the corresponding first gas injection flow calculation value can be calculated when the expected sintering end line is known, and the gas injection flow in the current state is adjusted to this value, 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] Among them, 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 sintering trolley speed, c is the thickness of the solid combustion zone, k1 is the heat transfer coefficient, h is the gas combustion heat, t is the gas injection duration, m is the material amount per unit sintering machine, 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, causing its initial temperature to increase by ΔT compared to 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 transfer downward and add to the material below the solid combustion zone; among them, the initial temperature increase ΔT of the material near the solid combustion zone to be ignited 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 carried 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 sintered ore layer, the gas combustion zone, the sintered ore layer between the gas-solid combustion zone, the solid combustion zone, and the mixed material layer; the flue gas is heated by the sintered 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. As 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; where 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, but can be considered a constant under stable operating conditions of the same sintering machine); ΔT: initial temperature increase of the solid combustion zone material caused by gas fuel, unit: K; m: material quantity 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 the 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, we can know that the heat of P2 is transferred to the material layer below the combustion zone. 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 material above the gas combustion zone will not be heated by the heat provided by the gas combustion zone, and the amount of heated material below the gas combustion zone is m*(z / H), and the duration is t;

[0095] Formula 6a can be derived

[0096]

[0097] T2: Initial temperature of the material; 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 the sintering material 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 z of the material layer under the gas combustion zone gradually decreases as the sintering machine moves forward. In the gas injection range, the average value can be 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 can obtain:

[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's important to note that the combustion of sintered solid fuels primarily involves four processes: 1. Preheating of charcoal powder; 2. Volatile analysis; 3. Combustion of volatiles; and 4. Residual carbon combustion. The latter three processes, involving complex coupled heat and mass transfer and chemical reactions, can be collectively referred to as the full combustion process. The total solid fuel combustion time, tt, can be roughly considered the sum of the time t1 required for the charcoal powder to reach its ignition point due to residual heat, and the time t2 required for the charcoal powder to fully burn. The effect of gas injection on the solid fuel combustion rate is primarily manifested in increasing the initial reactant temperature, thereby reducing the preheating time t1. Once solid fuel combustion begins, the full combustion time t2 remains unchanged.

[0107] Before and after gas injection, the heat transfer coefficient between the sintering material bed 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: heating rate of material layer, unit K / s;

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

[0111]

[0112] Obviously, the fuel thickness in the solid combustion zone divided by the total time of solid fuel combustion is the combustion velocity of the solid combustion zone moving downward, and the 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 can obtain:

[0121]

[0122] Right now

[0123]

[0124] Substituting Equation 12 into Equation 10, we obtain:

[0125]

[0126] Substituting Equation 15 into Equation 3, we obtain:

[0127]

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

[0129]

[0130] Here are some examples:

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

[0132] When the gas injection flow rate is 0Nm 3 / s can be calculated as follows:

[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 distribution position 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 25 mm and the material layer is considered to be 800 mm, the calculated position is 74.06 m. This matches the actual situation and shows that the above formula 16 is accurate.

[0136] As another example, when the gas injection flow rate is 0.006 Nm 3 / s can be calculated as follows:

[0137]

[0138] As another example, when the gas injection flow rate is 0.005 Nm 3 / s can be calculated as follows:

[0139]

[0140] The accuracy of Formula 16 can be verified through the above specific examples, which also shows 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 actual application, considering issues such as gas safety, the maximum volume fraction of gas injection is 0.8%, that is, gas injection has an effective injection flow rate range. It is understandable 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 / s. 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 calculated gas injection flow rate value, thereby adjusting the corresponding actual sintering end line to the desired sintering end line position. If the calculated first gas injection flow rate value is not within the effective flow rate adjustment range, an alarm can be issued to the target object to facilitate timely handling of the abnormal situation.

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

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

[0144] S12, obtaining the current calculation combustion zone center line according to the highlighted combustion zone area; wherein, the current calculation combustion zone center line 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 calculation combustion zone center line, the current calculation combustion zone center line that can represent the position of the highlighted combustion zone area is obtained through the highlighted combustion zone area. It can be understood that the method of obtaining the current calculation combustion zone center line 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 calculation combustion zone center line 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 components 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 completely 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 seen from this that the preset threshold value in this embodiment is set to ensure that the ideal sintering state is as close 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 value, 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 value, 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 it is 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 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:

[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 zones;

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

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

[0151] S134, when the number is less than the preset number, determine the current state as an abnormal sintering state and enter step S2; when the number is greater than or equal to the preset number, determine the current state as a normal sintering state, and maintain the current state 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, which affects 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 along the width of the sintering trolley into six visible light zones, with the preset number being three. In other embodiments, those skilled in the art may also set the preset number to other values. Furthermore, it should be noted that a more detailed visible light zone division facilitates analysis of 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 normal, maintaining the current sintering state and continuing production;

[0157] When the current sintering state is an abnormal sintering state, a 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 a message 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 description 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: Including steps: S1, obtaining a visible light imaging image of the current sintering machine tail section, and determining whether the current state is an abnormal sintering state based on 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 a tilt sensor for detecting the tilt angle of the sintering trolley on the sintering machine tail wheel and a visible light imaging device for capturing the visible light imaging image of the sintering machine tail section; the tilt sensor and the visible light imaging device are signal-linked; S2, when the current state is an abnormal sintering state, determining, based on a desired sintering end line and a pre-established position flow algorithm model, that the actual sintering end line in the current state is adjusted to a first calculated value of the gas injection flow rate corresponding to the desired sintering end line; wherein the position flow algorithm model includes a mapping relationship between the gas injection flow rate and the sintering end line; S3, when the first gas injection flow rate calculated value is within the effective flow rate adjustment range, regulating the gas injection regulating valve to adjust the current gas injection flow rate to the first gas injection flow rate calculated value; The location flow algorithm model in step S2 is specifically: Among them, 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 sintering trolley speed, c is the thickness of the solid combustion zone, k1 is the heat transfer coefficient, h is the gas combustion heat, t is the gas injection duration, m is the material amount per unit sintering machine, z is the material layer thickness below the gas combustion zone, and Cp is the average specific heat capacity of the sintering material.

2. The sintering finish line adjustment method based on abnormal sintering at 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 combustion zone in the visible light image according to the visible light image; if there is a highlighted combustion zone in the visible light image, executing steps S12 to S13; if there is no highlighted combustion zone in the visible light image, determining that the current state is an over-burned sintering state, and proceeding to step S2; S12, obtaining a currently calculated combustion zone centerline based on the highlighted combustion zone area; wherein the currently calculated combustion zone centerline is parallel to the top surface of the bottom material paved on 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 at the tail section according to claim 2 is characterized in that: 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", 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 zones; S132, determining whether each of the visible light subareas has a corresponding sub-highlight burning zone area; S133, counting the number of visible light subareas having the sub-highlight combustion zone area, and determining whether the number is less than a preset number; S134, when the number is less than the preset number, determine the current state as an abnormal sintering state and enter step S2; when the number is greater than or equal to the preset number, determine the current state as a normal sintering state, and maintain the current state to continue production.

4. The sintering finish line adjustment method based on abnormal sintering at the tail section according to claim 3 is characterized in that: The visible light imaging image is evenly divided into six visible light subareas 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 at 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 step is also included: when the vertical deviation distance is less than or equal to the preset threshold, 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 at the tail section according to claim 1 is characterized in that: The step S1 further includes the following steps: When the current state is normal, maintaining the current sintering state and continuing production; When the current 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 at the tail section according to claim 1 is characterized in that: The volume of the 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 at the tail section, characterized in that: It includes a sintering machine body, a gas injection device, a visible light imaging device and a control system. The sintering machine body includes 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, wherein: The gas injection device includes a gas injection main pipe and a plurality of gas injection branch pipes arranged in parallel along the width direction of the sintering trolley; a gas regulating valve is installed on the gas injection main pipe; each of the gas injection branch pipes is connected to the gas injection main pipe, and a plurality of burners 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 includes 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 taking a visible light image of the cross section of the tail wheel 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 runnable 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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