Evaluation method of blast furnace smelting speed uniformity based on blast furnace charge surface scanning

Abstract

The present invention relates to a blast furnace smelting speed uniformity evaluation method based on blast furnace charge surface scanning. According to the blast furnace charge surface scanning result, the blast furnace charge surface downward speed, each batch of ore thickness and each batch of coke thickness are calculated to form a blast furnace radial smelting speed curve; according to the blast furnace charge surface distribution characteristics, the charge surface is divided into differentiated areas in the radial direction, and the uniformity evaluation indexes of different areas of the blast furnace are also divided, so as to realize the evaluation of the blast furnace smelting speed uniformity according to the ore-coke ratio distribution of each charge distribution, and can fully consider the segregation effect of the charge layer thickness after each charge distribution.

Description

Technical Field

[0001] The invention relates to a blast furnace smelting speed uniformity evaluation method based on blast furnace charge surface scanning, and belongs to the technical field of blast furnace charge distribution analysis. Background Art

[0002] As a high-temperature, high-pressure, closed reaction vessel, the blast furnace undergoes complex gas-solid-liquid multiphase reactions. Its internal smelting conditions are difficult to monitor based on existing detection equipment and means. The stable and uniform descent of blast furnace charges and the uniform smelting inside the blast furnace are important foundations for the stability, high efficiency, and high yield of the blast furnace. During the blast furnace smelting process, the blast furnace smelting is inevitably unbalanced due to factors such as the blast furnace charge matrix, gas flow distribution, furnace activity, and uneven coal injection at the tuyere. Existing blast furnace operators often make subjective judgments based on blast furnace charge surface probes, charge surface scanning equipment, and their own experience. It is difficult to scientifically and effectively judge the uniformity of the blast furnace smelting speed. In addition, blast furnace operators have many areas of information to focus on and the blast furnace charge surface varies greatly. The accuracy and timeliness of their early warning responses are bound to be affected, often resulting in missing the best time for blast furnace adjustment.

[0003] Patent application 201110108018X provides a method for evaluating the uniformity of the distribution of the bellless blast furnace, which divides the horizontal section of the blocky strip material column of the blast furnace into three areas: the edge area, the middle area and the center area, and uses the parallel circuit analogy method to compare the blocky strip material columns in the three areas to a parallel circuit with three parallel branches, and refers to the calculation method of the parallel resistance to calculate the distribution uniformity index IBH with the ore-coke ratio as the content. The regional division of the patent application is relatively fixed, and the regions are divided according to 25%, 50%, and 25%. The present invention divides different regions according to the actual distribution characteristics of the material surface. In addition, the patent application evaluates the distribution uniformity of the ore-coke ratio. The present invention evaluates the uniformity of the material surface, not only for the ore-coke ratio, but also for the material surface after the ore distribution is completed. In addition, the present invention proposes that the curve difference area used for uniform evaluation is used to evaluate the circumferential distribution uniformity, which is also not available in the patent application.

[0004] Patent application 2020110022854 provides a method and system for judging and warning the uniformity of the descending charge of a blast furnace. In a blast furnace charging cycle with at least two probes in operation, the biased material index X1, the collapse and sliding material index X2, the suspended material index X3 and the uniformity index X4 of the charging are respectively constructed according to the acquired data; the charging stability index Z is constructed using X1, X2, X3 and X4 to comprehensively judge the uniformity of the descending charge of the blast furnace, and an early warning is issued when the index Z exceeds a predetermined threshold. This patent application uses a probe to evaluate the material surface, which has great limitations. The probe is equivalent to evaluating the uniformity of several points on the material surface. Its evaluation effect is prone to large deviations and is not globally representative.

[0005] In summary, the existing patents and prior art for evaluating the uniformity of blast furnace charge surface make it difficult to evaluate the circumferential smelting speed in the blast furnace. Judging only the downward speed of the blast furnace charge surface is difficult to reflect the actual smelting conditions inside the blast furnace. In particular, there will inevitably be certain differences in the blast furnace charge surface after each charge distribution in the blast furnace, which will also affect the evaluation of the downward speed of the blast furnace circumferential charge surface. Summary of the invention

[0006] In order to solve the above problems, the present invention discloses a method for evaluating the uniformity of blast furnace smelting speed based on blast furnace charge surface scanning, and its specific technical scheme is as follows:

[0007] The blast furnace smelting speed uniformity evaluation method based on blast furnace charge surface scanning comprises the following steps:

[0008] Step 1: Select the blast furnace to be tested, select the scanning height and scanning point within the blast furnace charge height range, and scan the blast furnace charge surface;

[0009] Step 2: The blast furnace is charged batch by batch, with coke charged first and ore charged next in each batch;

[0010] Step 3: First, coke the blast furnace. After coke is laid, scan the blast furnace at least twice with a time interval between adjacent times, calculate the downward speed of coke, continue to scan at intervals, calculate the downward speed of multiple cokes, and then obtain multiple coke downward speed curves until the blast furnace is laid, and record the time;

[0011] Step 4: After the blast furnace is ore-laid, scan the blast furnace more than twice with a time interval between adjacent scans, calculate the ore's downward speed, continue scanning at intervals, calculate the downward speeds of multiple ores, and then obtain the downward speed curves of multiple ores until the blast furnace is coked, and record the time;

[0012] Step 5: Repeat steps 3 and 4, continue production and monitoring;

[0013] Step 6: Calculate the coke thickness under this coke laying operation by using the last scan before coking and the first scan after coking. According to the multiple sets of data in step 5, obtain the thickness change curve of the coke layer.

[0014] Step 7: Use the last scan before ore laying and the first scan after ore laying to calculate the ore thickness under this ore laying operation, and reciprocate multiple sets of data according to step 5 to obtain the thickness change curve of the ore layer;

[0015] Step 8: Calculate the blast furnace smelting speed;

[0016] Step 9: Circumferential area division of blast furnace charge surface: According to the blast furnace charge matrix, the blast furnace is gradually divided into several circumferential areas from the center to the outside;

[0017] Step 10: Establish evaluation indicators based on the uniformity of the blast furnace charge surface and the circumferential smelting uniformity of the blast furnace, and establish evaluation indicators based on the blast furnace charge distribution matrix and the charge surface descending speed;

[0018] Step 11: Evaluate the uniformity of the circumferential smelting speed of the blast furnace according to the uniformity evaluation index in step 10, and count the maximum difference of the curves in different regions and the area between the curves;

[0019] Step 12: Based on the segregation of the blast furnace smelting speed determined in step 11, cumulative statistics are performed. If 50% segregation exists in this area for 8 consecutive hours, an instruction to adjust the blast furnace's distribution system is issued to the blast furnace, prompting the blast furnace operator to adjust the blast furnace in time; if 50% segregation exists for 3 consecutive days, the operator is warned to empty the tank or stop the wind to repair the distribution equipment.

[0020] Furthermore, in step 1, laser scanning or radar scanning is selected;

[0021] When laser scanning is used, multiple scanning points are selected on the scanning height surface of the blast furnace, installed according to the division evaluation curve, and the material surface is scanned according to the division evaluation curve;

[0022] When performing radar scanning, the entire material surface is scanned first, and then the data on the evaluation curve is extracted according to the division evaluation curve.

[0023] Furthermore, in steps 3 and 4, when the i-th batch of materials is laid, the blast furnace coke laying operation is first performed. After the coke laying is completed, the result of the first scan of the material surface is y 1 (i), time is t 1 (i) The result of the second scan is y 2 (i), time is t 2 (i) The result of the third scan is y 3 (i), time is t 3(i) Monitor in sequence until the blast furnace ore distribution operation is carried out. After the ore distribution is completed, the result of the first scan of the material surface is y' 1 (i) Time is t' 1 (i) The result of the second scan is y' 2 (i) Time is t' 2 (i) The result of the third scan is y' 3 (i) Time is t' 3 (i) Monitor in sequence until the next coking operation of the blast furnace is carried out;

[0024] Then the downward speed v of the i-th batch of materials after coking is C (i) is:

[0025]

[0026]

[0027] Calculate sequentially until the last set of data;

[0028] Each set of data obtains a set of material surface downward velocity curves after coking at adjacent moments;

[0029] The downward speed v of the i-th batch of materials after ore distribution O (i) is:

[0030]

[0031]

[0032] Calculate sequentially until the last set of data;

[0033] Each set of data obtains a set of downward velocity curves of the material surface after ore distribution at adjacent moments.

[0034] Furthermore, the specific calculation process of steps 6 and 7 is as follows:

[0035] The coke thickness ΔC(i) of the i-th batch is:

[0036] ΔC(i)=|y 1 (i) -y' last (i-1)+v O (i-1)(t 1 (i)-t' last (i-1))|

[0037] The thickness of the ore of the i-th batch ΔO(i) is:

[0038] ΔO(i)=|y' 1 (i)-y last (i-1)+vC (i)(t' 1 (i)-t last (i-1))|

[0039] (i-1) represents the i-1th batch of materials, and last represents the last scanning result before ore or coke is placed.

[0040] Furthermore, the step 8 is specifically as follows:

[0041] When the blast furnace is carrying out the coke laying operation, the smelting speed of the blast furnace is:

[0042]

[0043] When the blast furnace is carrying out the ore distribution operation, the smelting speed of the blast furnace is:

[0044]

[0045] v C (i) is the downward velocity of the coke layer between two adjacent scans after the i-th batch of materials is coked, v O (i) The downward speed of the ore layer between two adjacent scans after the i-th batch of materials is laid.

[0046] Furthermore, in step 9, the circumferential area of ​​the blast furnace charge surface is divided into: a central coke area, an intermediate ring area and a marginal ore area from the center to the edge.

[0047] Furthermore, the step 10: based on the evaluation index of the uniformity of the blast furnace material surface and the blast furnace circumferential smelting uniformity, the evaluation index is established based on the blast furnace material distribution matrix and the material surface downward speed, specifically:

[0048] The central focus area is: the maximum difference between the two radial smelting speed curves does not exceed 5, and the area between the curves does not exceed 5 / 2*(the radius length of the central focus area);

[0049] The middle annular zone is: the maximum difference between the two radial smelting speed curves does not exceed 10, and the area between the curves does not exceed 10 / 2*(the difference between the maximum radius and the minimum radius of the middle annular zone);

[0050] The marginal mining area is: the maximum difference between the two radial smelting speed curves does not exceed 10, and the area between the curves does not exceed 10 / 2*(the difference between the maximum radius and the minimum radius of the marginal mining area).

[0051] Furthermore, the step 11 is specifically as follows: in the same region, when the maximum difference between the two scanning results is greater than the uniformity evaluation index, or the area difference of the scanning curve is greater than the uniformity evaluation index, it is determined that segregation exists in the region;

[0052] In the same region, only when the maximum difference between the current and the next two scanning results is not greater than the uniformity evaluation index and the area difference of the scanning curve is less than the uniformity evaluation index, it is determined that there is no segregation in this region.

[0053] Furthermore, the divided evaluation curve is a line where multiple diameters are located on the blast furnace scanning plane, and the scanning plane is divided into multiple evaluation units through the line.

[0054] The beneficial effects of the present invention are:

[0055] The present invention is based on the blast furnace charge surface scanning technology and proposes a blast furnace smelting speed uniformity evaluation method. According to the blast furnace charge surface scanning result, the blast furnace charge surface downward speed, the ore thickness of each batch and the coke thickness of each batch are calculated to form a blast furnace radial smelting speed curve; according to the blast furnace charge surface distribution characteristics, the charge surface is divided into differentiated areas in the radial direction, and the uniformity evaluation indicators of different areas of the blast furnace are also divided, so as to realize the evaluation of the blast furnace smelting speed uniformity according to the ore-coke ratio distribution of each charge distribution.

[0056] The present invention can perform circumferential evaluation of the smelting speed in the blast furnace according to the blast furnace charge surface conditions in real time. The existing evaluation system based on the scanning of the charge surface in the furnace can evaluate the smelting speed in different areas in real time according to the thickness of ore and coke after each charging and the falling speed of the charge surface, and can fully consider the segregation effect of the charge layer thickness after each charging.

[0057] The division of radial material surface areas in the blast furnace of the present invention can fully take into account the different characteristics of ore and coke thickness distribution under different material distribution matrices, and the evaluation of material surface downward speed and smelting speed is bound to be different. The material distribution in the present invention is a typical center coke + platform funnel material distribution mode, which is gradually divided into three areas from the center of the blast furnace to the outside. The distribution characteristics of ore and coke in different areas are bound to be different. The evaluation of the center and edge of the blast furnace in sections can more accurately reflect the real situation of each area, and the monitoring results can be used in reverse to correctly guide the material distribution operation and the material distribution amount of each area. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 This is a schematic diagram of the process of the present invention, taking two scans after coke placement and ore placement as an example.

[0059] Figure 2 It is a schematic diagram of the material surface fitting curve in an embodiment of the present invention.

[0060] Figure 3 Schematic diagram of material surface velocity curve in an embodiment of the present invention.

[0061] Figure 4 Schematic diagram of ore and coke thickness curve in an embodiment of the present invention.

[0062] Figure 5 It is a schematic diagram of the iron ore smelting speed curve in an embodiment of the present invention.

[0063] Figure 6 It is a schematic diagram of the material level evaluation curve in the blast furnace in an embodiment of the present invention.

[0064] Figure 7 Schematic diagram of the division of circumferential areas of the material surface in a blast furnace in an embodiment of the present invention.

[0065] Figure 8 It is a schematic diagram of comparing radial smelting speeds of blast furnaces in an embodiment of the present invention. DETAILED DESCRIPTION

[0066] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0067] The blast furnace smelting speed uniformity evaluation method based on blast furnace charge surface scanning comprises the following steps:

[0068] Step 1: Select the blast furnace to be tested, select the scanning height and scanning point within the blast furnace charge height range, and scan the blast furnace charge surface.

[0069] Select Laser Scan or Radar Scan.

[0070] When laser scanning is used, multiple scanning points are selected on the scanning height surface of the blast furnace, installed according to the division evaluation curve, and the material surface is scanned according to the division evaluation curve.

[0071] When performing radar scanning, the entire material surface is scanned first, and then the data on the evaluation curve is extracted according to the division evaluation curve.

[0072] In order to more accurately reflect the material surface conditions, the present invention divides the material surface into multiple evaluation units, divides the evaluation curve into multiple diameter lines on the blast furnace scanning plane, and the interval between adjacent straight lines is the evaluation unit interval.

[0073] Step 3: First, coke the blast furnace. After coke is laid, scan the blast furnace at least twice with a time interval between the two times, calculate the downward speed of coke, continue to scan at intervals, calculate the downward speed of multiple cokes, and then obtain multiple downward speed curves of coke until the blast furnace is laid, and record the time;

[0074] Step 4: Scan the ore in the blast furnace more than twice with a time interval between the two times, calculate the downward speed of the ore, continue scanning at intervals, calculate the downward speeds of multiple ores, and then obtain the downward speed curves of multiple ores until the blast furnace is coked, and record the time.

[0075] In steps 3 and 4, when the i-th batch of materials is laid, the blast furnace coke laying operation is first performed. After the coke laying is completed, the result of the first scan of the material surface is y 1 (i), time is t 1 (i) The result of the second scan is y 2 (i), time is t 2 (i) The result of the third scan is y 3 (i), time is t 3 (i) Monitor in sequence until the blast furnace ore distribution operation is completed. After the ore distribution is completed, the result of the first scan of the material surface is y' 1 (i) Time is t' 1 (i) The result of the second scan is y' 2 (i) Time is t' 2 (i) The result of the third scan is y' 3 (i) Time is t' 3 (i) Monitor in sequence until the blast furnace coke laying operation begins.

[0076] Then the downward speed v of the i-th batch of materials after coking is C (i) is:

[0077]

[0078]

[0079] Calculate sequentially until the last set of data;

[0080] The downward speed v of the i-th batch of materials after ore distribution O (i) is:

[0081]

[0082]

[0083] Calculate sequentially until the last set of data.

[0084] Step 5: Repeat steps 3 and 4, continue production and monitoring;

[0085] Step 6: The last scan before coking and the first scan after coking are used to calculate the coke thickness under this coking operation, and obtain a thickness variation curve of the coke layer;

[0086] Step 7: Use the last scan before ore laying and the first scan after ore laying to calculate the ore thickness under this ore laying operation and obtain the thickness change curve of the ore layer.

[0087] The specific calculation process of steps 6 and 7 is:

[0088] The coke thickness ΔC(i) of the i-th batch is:

[0089] ΔC(i)=|y 1 (i) -y' last (i-1)+v O (i-1)(t 1 (i)-t' last (i-1))|

[0090] The thickness of the ore of the i-th batch ΔO(i) is:

[0091] ΔO(i)=|y' 1 (i)-y last (i-1)+v C (i)(t' 1 (i)-t last (i-1))|

[0092] (i-1) represents the i-1th batch of material.

[0093] Step 8: Calculate the smelting rates of the coke layer and the ore layer to obtain the blast furnace smelting rate;

[0094] When the blast furnace is carrying out the coke laying operation, the smelting speed of the blast furnace is:

[0095]

[0096] When the blast furnace is carrying out the ore distribution operation, the smelting speed of the blast furnace is:

[0097]

[0098] v C (i) is the downward velocity of the coke layer between two adjacent scans after the i-th batch of materials is coked, v O (i) The downward speed of the ore layer between two adjacent scans after the i-th batch of materials is laid.

[0099] The smelting speed reflects the speed of blast furnace smelting. If the consumption rate of ore and coke is fast, it can indirectly indicate that the smelting is fast. If the consumption rate of ore and coke is slow, it can indirectly indicate that the smelting is slow.

[0100] Step 9: Division of circumferential areas of the blast furnace charge surface: Based on the blast furnace charge matrix, it is divided from the center of the blast furnace to the edge in sequence: central coke area, middle ring area and edge ore area.

[0101] Step 10: Establish evaluation indicators based on the uniformity of the blast furnace charge surface and the circumferential smelting uniformity of the blast furnace, and establish evaluation indicators based on the blast furnace charge distribution matrix and the charge surface descending speed;

[0102] Based on the evaluation index of blast furnace material surface uniformity and blast furnace circumferential smelting uniformity, the evaluation index is established based on the blast furnace material distribution matrix and material surface downward speed.

[0103] The central focus area is: the maximum difference between the two radial smelting speed curves does not exceed 5, and the area between the curves does not exceed 5 / 2*(the radius length of the central focus area). Figure 8 The radius of the center focus area is 1400, and the area between the curves does not exceed 3500 (5 / 2*1400=3500).

[0104] The middle annular zone is: the maximum difference between the two radial smelting speed curves does not exceed 10, and the area between the curves does not exceed 10 / 2*(the difference between the maximum radius and the minimum radius of the middle annular zone); Figure 8 The difference between the maximum and minimum radii of the middle ring zone is 2600, so the area between the curves does not exceed 13000.

[0105] (10 / 2*2600=13000).

[0106] The marginal mining area is: the maximum difference between the two radial smelting speed curves does not exceed 10, and the area between the curves does not exceed 10 / 2*(the difference between the maximum radius and the minimum radius of the marginal mining area). Figure 8 The difference between the maximum radius and the minimum radius of the middle marginal mining area is 1400, and the area between the curves does not exceed 7000 (10 / 2*1400=7000).

[0107] Step 11: Evaluate the uniformity of the circumferential smelting speed of the blast furnace according to the uniformity evaluation index in step 10, and count the maximum difference of the curves in different regions and the area between the curves;

[0108] In the same area, when the maximum difference between the two scanning results is greater than the uniformity evaluation index, or the area difference of the scanning curve is greater than the uniformity evaluation index, it is determined that segregation exists in this area;

[0109] In the same region, only when the maximum difference between the current and the next two scanning results is not greater than the uniformity evaluation index and the area difference of the scanning curve is less than the uniformity evaluation index, it is determined that there is no segregation in this region.

[0110] Step 12: Based on the segregation of the blast furnace smelting speed determined in step 11, cumulative statistics are performed. If 50% segregation exists in this area for 8 consecutive hours, an instruction to adjust the blast furnace's distribution system is issued to the blast furnace, prompting the blast furnace operator to adjust the blast furnace in time; if 50% segregation exists for 3 consecutive days, the operator is warned to empty the tank or stop the wind to repair the distribution equipment.

[0111] See also Figure 8 , Figure 8 The two curves do not overlap, indicating segregation. The larger the area of ​​the non-overlapping region, the greater the segregation.

[0112] A specific embodiment of the present invention is given below in conjunction with the accompanying drawings. This embodiment takes only two scans after ore and coke are placed as an example to show the actual operation process of this patent:

[0113] The first step is to select the blast furnace to be tested. Figure 6 Install a laser scanning instrument according to the division evaluation curve shown, and scan the material surface according to the division evaluation curve; Figure 6 There are 4 evaluation curves in the blast furnace, which can be increased or decreased according to actual requirements. The more accurate the material surface evaluation is, the more evaluation curves are needed. After the scanning equipment is installed, the equipment is calibrated to obtain the scanning results of the blast furnace material surface. Figure 6 By dividing the evaluation curve, multiple radial distribution curves of the material surface can be obtained, such as Figure 2 As shown, the horizontal axis is the distance from the inner periphery of the blast furnace to the center of the blast furnace in the radial direction of the blast furnace, and the vertical axis is the distance from the material surface to the 0 material line;

[0114] The second step is to set a reasonable material surface scanning procedure and scanning time interval; Figure 1 As shown in the figure, for the i-th batch of material distribution, the blast furnace first performs the coke distribution operation. After the coke distribution is completed, the result of the first scan of the material surface is y 1 (i), time is t 1 (i) The result of the second scan is y 2 (i), time is t 2 (i) During the blast furnace ore distribution operation, after the ore distribution is completed, the result of the first scan of the material surface is y' 1 (i) Time is t' 1 (i) The result of the second scan is y' 2 (i) Time is t' 2 (i);

[0115] The third step is to calculate the downward speed of the material surface. The downward speed of the material surface of the i-th batch of materials after coking is:

[0116]

[0117] The downward speed of the i-th batch of materials after ore distribution is:

[0118]

[0119] Get as Figure 3 The downward speed curve of the material surface is shown.

[0120] The fourth step is to calculate the thickness of the coke layer of the ore. The thickness of the ore of the i-th batch is:

[0121] The coke thickness ΔC(i) of the i-th batch is:

[0122] ΔC(i)=|y 1 (i) -y' 2 (i-1)+v O (i-1)(t 1 (i)-t' 2 (i-1))|

[0123] The thickness of the ore of the i-th batch ΔO(i) is:

[0124] ΔO(i)=|y' 1 (i)-y 2 (i-1)+v C (i)(t' 1 (i)-t 2 (i-1))|

[0125] Get as Figure 4 Coke and ore thickness curves shown.

[0126] Step 5: Calculate the smelting speed:

[0127] When the blast furnace is carrying out the coke laying operation, the smelting speed of the blast furnace is:

[0128]

[0129] When the blast furnace is carrying out the ore distribution operation, the smelting speed of the blast furnace is:

[0130]

[0131] Get as Figure 5 Blast furnace smelting speed shown.

[0132] Step 6: The circumferential area division of the blast furnace charge surface. According to the blast furnace charge distribution matrix, the blast furnace is divided into several areas along the radial direction. For example, in this embodiment, according to the blast furnace charge distribution matrix and Figure 4 Medium ore coke surface distribution radial material surface distribution thickness, such as Figure 7 As shown, the blast furnace is gradually divided into three areas outward from the center. Area 1 has a radius of 1400mm and is defined as the central focus area. Area 2 is an intermediate ring area with an inner diameter of 1400mm and an outer diameter of 4000mm. The remaining part is the edge mine area.

[0133] The seventh step is to establish evaluation indicators for the uniformity of the downward flow of the blast furnace charge surface and the uniformity of the circumferential smelting of the blast furnace.

[0134] Area 1: Central focus area stipulates that the maximum difference between the two radial smelting speed curves does not exceed 5, and the area between the curves does not exceed 3500 (5 / 2*1400=3500);

[0135] Area 2: The middle annular zone, the maximum difference between the two radial smelting speed curves does not exceed 10, and the area between the curves does not exceed 13000 (10 / 2*2600=13000);

[0136] Area 3: The marginal mine area stipulates that the maximum difference between two radial smelting speed curves shall not exceed 10, and the area between the curves shall not exceed 7000 (10 / 2*1400=7000).

[0137] Step 8: Evaluate the uniformity of the smelting speed in the circumferential direction of the blast furnace according to the uniformity evaluation index in step 7, and count the maximum difference of the curves in different regions and the area between the curves. Figure 8 As shown, Figure 5 The smelting speed curve is symmetrical along the center. Figure 8 The medium cyan area is the area between the two curves.

[0138] In region 1, the maximum difference is 1.1<5, and the area between the two curves is 283<3500;

[0139] The maximum difference in region 2 is 13.1>10, and the area between the two curves is 13156>13000;

[0140] In region 3, the maximum difference is 3.3<10, and the area between the two curves is 3121<7000;

[0141] Therefore, in area 2, that is, the middle ring zone with an inner diameter of 1400mm and an outer diameter of 4000mm, there is downward segregation of the material surface or segregation of the smelting speed.

[0142] The ninth step is to make cumulative statistics based on the segregation of the blast furnace smelting speed determined in the eighth step. If there is 50% segregation in this area for 8 consecutive hours, an instruction to adjust the distribution system of the blast furnace can be issued to prompt the blast furnace operator to adjust the blast furnace in time; if there is 50% segregation for 3 consecutive days, the operator can be warned to empty the tank or stop the wind to repair the distribution equipment.

[0143] The present invention adopts a three-region differentiated evaluation method. The coke thickness in region 1 is significantly greater than the ore thickness, and its surface descending speed and smelting speed are significantly different from those in other regions. Figure 4 and Figure 8 It can also be verified that the evaluation indicators used are lower than those of region 2 and region 3, and the application of this type of evaluation indicator is more scientific.

[0144] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A method for evaluating uniformity of blast furnace smelting speed based on blast furnace charge surface scanning, characterized in that: The following steps are involved: Step 1: Select the blast furnace to be tested, select the scanning height and scanning point within the blast furnace charge height range, and scan the blast furnace charge surface; Step 2: The blast furnace is charged batch by batch, with coke charged first and ore charged next in each batch; Step 3: First, coke the blast furnace, and then scan the blast furnace more than twice with a time interval between adjacent scans, calculate the downward speed of coke, continue to scan at intervals, calculate the downward speed of multiple cokes, and then obtain multiple coke downward speed curves until the blast furnace is ore-laid, and record the time; Step 4: After the blast furnace is ore-laid, scan the blast furnace more than twice with a time interval between adjacent scans, calculate the ore's downward speed, continue scanning at intervals, calculate the downward speeds of multiple ores, and then obtain the downward speed curves of multiple ores until the blast furnace is coked, and record the time; Step 5: Repeat steps 3 and 4, continue production and monitoring; Step 6: Calculate the coke thickness under this coke laying operation by using the last scan before coking and the first scan after coking. According to the multiple sets of data in step 5, obtain the thickness change curve of the coke layer. Step 7: Use the last scan before ore laying and the first scan after ore laying to calculate the ore thickness under this ore laying operation, and reciprocate multiple sets of data according to step 5 to obtain the thickness change curve of the ore layer; Step 8: Calculate the blast furnace smelting speed; Step 9: Circumferential area division of blast furnace charge surface: According to the blast furnace charge matrix, the blast furnace is gradually divided into several circumferential areas from the center to the outside; Step 10: Establishing evaluation indexes for uniformity of blast furnace charge surface downward movement and uniformity of blast furnace circumferential smelting, and establishing evaluation indexes based on blast furnace charge distribution matrix and charge surface downward movement speed; Step 11: Evaluate the uniformity of the circumferential smelting speed of the blast furnace according to the uniformity evaluation index of step 10, and count the maximum difference of the radial smelting speed curves in different areas and the area between the curves; Step 12: Based on the segregation of the blast furnace smelting speed determined in step 11, cumulative statistics are performed. If 50% segregation exists in this area for 8 consecutive hours, an instruction to adjust the blast furnace's distribution system is issued to the blast furnace, prompting the blast furnace operator to adjust the blast furnace in time; if 50% segregation exists for 3 consecutive days, the operator is warned to empty the tank or stop the wind to repair the distribution equipment.

2. The method for evaluating blast furnace smelting rate uniformity based on blast furnace charge surface scanning according to claim 1, characterized in that: Select laser scanning or radar scanning in step 1; When laser scanning is used, multiple scanning points are selected on the scanning height surface of the blast furnace, installed according to the division evaluation curve, and the material surface is scanned according to the division evaluation curve; When scanning by radar, the entire material surface is scanned first, and then the data on the evaluation curve is extracted according to the division evaluation curve; The divided evaluation curve is a line where multiple diameters are located on the blast furnace scanning plane, and the scanning plane is divided into multiple evaluation units through the line.

3. The method for evaluating blast furnace smelting rate uniformity based on blast furnace charge surface scanning according to claim 1, characterized in that: In the steps 3 and 4, when the i-th batch of materials is laid, the blast furnace coke laying operation is first carried out. After the coke laying is completed, the result of the first scan of the material surface is y1(i), and the time is t1(i). The result of the second scan of the material surface is y2(i), and the time is t2(i). The result of the third scan of the material surface is y3(i), and the time is t3(i). The monitoring is carried out in sequence until the blast furnace ore laying operation is carried out. After the ore laying is completed, the result of the first scan of the material surface is y'1(i), and the time is t'1(i). The result of the second scan of the material surface is y'2(i), and the time is t'2(i). The result of the third scan of the material surface is y'3(i), and the time is t'3(i). The monitoring is carried out in sequence until the blast furnace carries out the next coke laying operation; Then the downward speed v of the i-th batch of materials after coking is C (i) is: Calculate sequentially until the last set of data; Each set of data obtains a set of material surface downward velocity curves after coking at adjacent moments; The downward speed v of the i-th batch of materials after ore distribution O (i) is: Calculate sequentially until the last set of data; Each set of data obtains a set of downward velocity curves of the material surface after ore distribution at adjacent moments.

4. The method for evaluating blast furnace smelting rate uniformity based on blast furnace charge surface scanning according to claim 3, characterized in that: The specific calculation process of steps 6 and 7 is: The coke thickness ΔC(i) of the i-th batch is: ΔC(i)=|y1(i)-y' last (i-1)+v O (i-1)(t1(i)-t' last (i-1))| The thickness of the ore of the i-th batch ΔO(i) is: ΔO(i)=|y'1(i)-y last (i-1)+v C (i)(t'1(i)-t last (i-1))| (i-1) represents the i-1th batch of materials, and last represents the last scanning result before ore or coke is placed.

5. The method for evaluating blast furnace smelting rate uniformity based on blast furnace charge surface scanning according to claim 4, characterized in that: The step 8 is specifically as follows: When the blast furnace is carrying out the coke laying operation, the smelting speed of the blast furnace is: v c (i)∈{v C1 (i),v C2 (i)……v Clast (i)} When the blast furnace is carrying out the ore distribution operation, the smelting speed of the blast furnace is: v O (i)∈{v O1 (i),v O2 (i)……v Olast (i ) } v C (i) is the downward velocity of the coke layer between two adjacent scans after the i-th batch of materials is coked, v O (i) The downward speed of the ore layer between two adjacent scans after the i-th batch of materials is laid.

6. The method for evaluating blast furnace smelting rate uniformity based on blast furnace charge surface scanning according to claim 1, characterized in that: In step 9, the circumferential area of ​​the blast furnace charge surface is divided into: a central coke area, an intermediate ring area and a marginal ore area from the center to the edge.

7. The method for evaluating blast furnace smelting rate uniformity based on blast furnace charge surface scanning according to claim 6, characterized in that: The step 10: establishing the evaluation index of the uniformity of the blast furnace material surface downward movement and the uniformity of the blast furnace circumferential smelting. The evaluation index is established based on the blast furnace material distribution matrix and the material surface downward movement speed. Specifically, the evaluation index is: The central focus area is: the maximum difference between the two radial smelting speed curves does not exceed 5, and the area between the curves does not exceed 5 / 2*(the radius length of the central focus area); The middle annular zone is: the maximum difference between the two radial smelting speed curves does not exceed 10, and the area between the curves does not exceed 10 / 2*(the difference between the maximum radius and the minimum radius of the middle annular zone); The marginal mining area is: the maximum difference between the two radial smelting speed curves does not exceed 10, and the area between the curves does not exceed 10 / 2*(the difference between the maximum radius and the minimum radius of the marginal mining area).

8. The method for evaluating blast furnace smelting rate uniformity based on blast furnace charge surface scanning according to claim 7, characterized in that: The step 11 is specifically as follows: in the same region, when the maximum difference between the two scanning results is greater than the uniformity evaluation index, or the area difference of the scanning curve is greater than the uniformity evaluation index, it is determined that segregation exists in the region; In the same region, only when the maximum difference between the current and the next two scanning results is not greater than the uniformity evaluation index and the area difference of the scanning curve is less than the uniformity evaluation index, it is determined that there is no segregation in this region.

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