Method for judging and processing suspended material part of blast furnace

Abstract

The present application relates to a kind of judgment method and processing method of blast furnace suspension material position, the judgment method of blast furnace suspension material position is used to judge the position of blast furnace suspension material, the processing method of blast furnace suspension material position, including if upper suspension material control wind speed and increase the coke of maintaining material surface shape, " sit material " by different ways is selected according to different suspension material position, quantitative calculation supplementary net coke weight, determine the distribution of net coke increase way.The present application has the advantages that: different furnace condition recovery method, parameter setting rule, coke adding method are invented for different suspension material position, improve the recovery speed after blast furnace suspension material;In upper suspension material, maintaining material surface shape can speed up subsequent wind process, reduce the possibility of secondary collapse, slide material accident;According to different suspension material position, different ways are selected to reduce wind " sit material ", according to different suspension material position, corresponding wind reduction method is adopted, can as far as possible speed up furnace condition recovery process, realize the optimization of suspension material recovery process.

Description

Technical Field

[0001] This invention relates to the field of iron and steel metallurgy, and in particular to a method for determining and processing the suspended material position in a blast furnace. Background Technology

[0002] Maintaining stable and smooth operation of the blast furnace smelting process is of paramount importance. Accidents such as pipe malfunctions, material collapse, and material suspension severely impact stable blast furnace production, and in severe cases, can lead to major accidents. Material suspension is one of the most common serious abnormalities in blast furnace production caused by deterioration of furnace conditions. It manifests as probe stagnation and a significant increase in hot blast pressure, but is essentially caused by the descent of the burden falling below the combined upward force of local gas buoyancy and furnace wall friction, resulting in the burden ceasing to descend. The causes of material suspension include a series of complex factors such as deterioration of furnace conditions, abnormal gas flow distribution within the furnace, violent fluctuations in the softening zone, slag shedding, blockage of passages after local pipe malfunctions, and deterioration of the physicochemical properties of the burden. In practice, after material suspension occurs, it is necessary to significantly reduce blast and slowly restore the furnace after reducing smelting intensity. This has a significant impact on the blast furnace's pig iron production capacity and fuel consumption. Secondary material suspension or secondary blast reduction due to errors during continuous material suspension or restoration can lead to prolonged abnormal furnace conditions and substantial economic losses.

[0003] Traditional blast furnace charge handling primarily relies on operators' experience to manually "settle" the charge based on the probe readings (settle refers to reducing blast to allow the stagnant charge surface to settle). Charge handling mainly consists of two processes: "settle" and "recovery." Previous methods for handling charge suspension have significant drawbacks:

[0004] 1. Lack of accurate judgment on the location of suspended material. Blast furnace suspended material can be divided into upper suspended material and lower suspended material. The causes and characteristics of the two are different, and the corresponding treatment methods are also different. Operators usually adopt a large reduction of air volume for both upper and lower suspended material, and there is no possibility of optimizing the air volume and recovery progress.

[0005] 2. During the "sit" and "recovery" processes of suspended material, the control of parameters relies entirely on the operator's experience. Summary of the Invention

[0006] The purpose of this invention is to provide a method for determining and processing the suspended material location in a blast furnace, which improves the accuracy of the determination of the suspended material location, allows for differentiated processing according to the suspended material location, enables rapid and stable recovery of the furnace condition after the suspended material is suspended, and reduces the adverse effects of the suspended material on the blast furnace condition.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A method for determining the location of suspended burden in a blast furnace, comprising:

[0009] 1) The presence of one or more of the following characteristics indicates that the location of the blast furnace suspension is in the upper part of the blast furnace body, as follows:

[0010] a. The static pressure on the upper part of the blast furnace body rises to a peak at one or more points, the pressure rise rate is >0.5KPa / s, and the peak time is earlier than the hot blast pressure rise time;

[0011] b. Both the static pressure at the top of the blast furnace body and the static pressure in the belly of the blast furnace showed peak values, but the peak value of the static pressure at the top of the blast furnace body appeared earlier than the rise time of the static pressure in the belly of the blast furnace.

[0012] c. Both the static pressure at the top of the blast furnace body and the static pressure in the belly of the blast furnace showed peak values, but the rate of increase of static pressure at the top of the blast furnace body was greater than the rate of increase of static pressure in the belly of the blast furnace.

[0013] 2) The following characteristics indicate that the location of the blast furnace suspension is in the lower part of the blast furnace body:

[0014] The static pressure in the blast furnace belly or the hot blast pressure shows a peak increase, with a pressure increase rate >0.5 kPa / s, while the static pressure in the blast furnace body decreases or shows no significant change.

[0015] Methods for handling blast furnace suspending points where the current blast furnace operation is determined to be in a state of suspension include:

[0016] S1. If it is upper suspended material, control the wind speed and increase the coke to maintain the shape of the material surface.

[0017] S2. Select different methods to reduce airflow and "settle the material" according to different parts of the suspended material;

[0018] S3. Quantitatively calculate and supplement the net coke weight;

[0019] S4. Determine the method of adding coke to the fabric.

[0020] In S1, the wind speed is controlled as follows:

[0021] Reduce the blast furnace inlet air volume to a value of 100–500 m³ / min. The blast furnace top pressure setpoint decreases as the air volume is reduced, eventually decreasing to P2, as shown in the following formula:

[0022]

[0023] In formula ①, P2 represents the setpoint of the blast furnace top pressure after blast reduction, in kPa; P1 represents the setpoint of the blast furnace top pressure before blast reduction, in kPa. 热2 This represents the hot blast pressure value after the blast furnace blast rate is reduced, and the unit is kPa. The value represents the hot blast pressure before the blast furnace blast rate is reduced, in kPa; η represents the top pressure coefficient for the suspended charge furnace condition, a dimensionless unit, with a value of 0.3 to 0.8.

[0024] In S1, there are two methods to maintain the shape of the coke surface: Method 1 and Method 2, as follows:

[0025] Method 1: The net coke feeding method adopts a single-ring feeding method. The tilting angle of the single-ring feeding is the weighted average of the tilting angles and the number of feeding rings of all rings in the current blast furnace feeding matrix, except for the central coke feeding.

[0026] Method 2: The clean-burning fabric adopts a single-ring fabric method, and the tilting angle of the single-ring fabric is α:

[0027] First, based on infrared imaging of the material surface at the top of the furnace, determine the location of point Q, which has the largest temperature drop before and after the material is suspended within the circumferential cross-section of the furnace throat.

[0028] The distance r from point Q to the center point of the furnace throat is obtained according to the cloth landing point formula, as follows:

[0029]

[0030] In Formula ②: t is the falling time of the furnace charge after leaving the chute, in seconds; v2 is the velocity of the furnace charge when leaving the chute, in m / s; l is the effective length of the chute, in meters; α is the chute inclination angle, in degrees; and w is the angular velocity of the chute, in rad / s.

[0031]

[0032] In formula ③: v0 is the initial velocity of the furnace charge after falling into the chute, in m / s; λ is the velocity loss coefficient; v2 is the velocity of the furnace charge when leaving the chute, in m / s; g is the acceleration due to gravity, in m / s²; l is the effective length of the chute, in m; α is the chute inclination angle, in °; μ is the friction coefficient between the furnace charge and the chute; w is the angular velocity of the chute, in rad / s.

[0033]

[0034] In formula ④: v0 is the material flow velocity before falling into the chute, in m / s; F is the measured flow rate of the furnace charge at the throttle valve, in m³ / s; S is the projected area of ​​the throttle valve, in m²; l S d0 represents the perimeter of the throttle valve, in meters; d0 represents the average particle size of the furnace charge, in meters.

[0035] Calculate the tilt angle α corresponding to the landing radius r of point Q;

[0036] Finally, according to the tilting angle α, the coke single-ring fabric is placed on the ring at the position of the point with the maximum temperature drop (i.e., point Q).

[0037] In S2, during the "charging" process, the blast furnace top pressure is maintained at 10% to 30% higher than the top pressure during conventional charging and air reduction by reducing the manual opening of the blast furnace top TRT bypass valve group.

[0038] Different methods of reducing air pressure are adopted depending on the location of the suspended material to accelerate the blast furnace return air process. The details are as follows: 1) When the suspended material is in the upper part:

[0039] Change the blast furnace top pressure regulation to manual and set the valve opening to 55%-85% of the TRT manual valve opening during non-accident shutdown and reduced blast conditions of the blast furnace.

[0040] The air volume is reduced to 30%-80% of the full air volume using a vent valve, and the process ends when the material collapses as the probe stops moving.

[0041] After the material collapses, quickly return air at 200-400 m³ / min to accelerate the furnace condition recovery process, and then gradually increase the air volume to restore the air volume;

[0042] 2) When the suspended material is at the bottom:

[0043] Change the blast furnace top pressure regulation to manual and set the valve opening to 40% to 60% of the TRT manual valve opening under non-accident shutdown and reduced blast conditions of the blast furnace.

[0044] The air volume is reduced to 30%-80% of the full air volume using a vent valve, and the process ends when the material collapses as the probe stops moving.

[0045] After the material collapses, do not immediately return the airflow. Wait until the probe descends evenly without stagnation, and the material continues to slide for 5-10 minutes or more before gradually increasing the airflow to restore the air volume.

[0046] In S3, the net coke weight is calculated quantitatively using the following formula:

[0047]

[0048] In formula ⑤, M 焦L1 represents the total net coke mass that needs to be replenished after the blast furnace is suspended, in tons (t); L2 represents the deepest material line detected by each probe after the blast furnace collapse, in meters (m); L1 represents the normal set material line of the blast furnace, in meters (m); T2 represents the maximum value of the temperature points at the top of the blast furnace during the blast furnace collapse process, in degrees Celsius (°C); T1 represents the maximum value of the temperature points at the top of the blast furnace before the blast furnace collapse, in degrees Celsius (°C); a represents the coke replenishment coefficient based on the blast furnace's daily fuel ratio and coke mass, with a value range of 0.5-1.5, dimensionless; b represents the coke replenishment coefficient based on the pipeline stroke, with a value range of 0.5-1.7, dimensionless; m1 represents the batch weight of coke charged into the blast furnace before the collapse, in tons / batch.

[0049] The net coke batch number can be obtained using formula ⑤, as follows:

[0050] N = M 焦 / m1 ⑥

[0051] In formula ⑥, N represents the number of net coke batches, N is an integer, and the unit is batch; the net coke weight of each batch is set to M. 焦 / N tons, so that the total weight of N batches of net coke is M. 焦 .

[0052] In S4, the formula for calculating net coke is added to formula ④ as follows:

[0053] M 焦 =A+B ⑦

[0054] A=(L2-L1) / 0.5·a·m1 ⑧

[0055] B=(T2-T1) / 150·b·m1 ⑨

[0056] In formulas ⑦-⑨, A represents the net coke from the material replenishment line and B represents the net coke from the heat source replenished by the pipeline.

[0057] The method of adding clean-burning fabric is as follows:

[0058] 1) The calculation formula for the upper suspended material is as follows:

[0059] NA = A / m1 ⑩

[0060] In formula 10, NA represents the number of batches of net coke in the collapse replenishment line, that is, how many batches or tanks of net coke need to be added to the collapse replenishment line. NA is an integer, and the unit is batch. The net coke of NA tanks in the collapse replenishment line is distributed according to the coke ring position inclination angle of the original blast furnace distribution matrix. The net coke B part of the pipeline supplementary heat source is NB = (N-NA) batches of net coke distributed according to the original blast furnace matrix ring position minus the center ring position. The net coke B part of the pipeline supplementary heat source is distributed in the blast furnace annular zone area.

[0061] 2)Lower hanging material

[0062] When N≥3, take 1 to 2 batches of net coke fabric at the center angle, and the remaining net coke fabric is laid out according to the original fabric matrix.

[0063] When N<3, each batch of net coke is laid out in the original fabric matrix.

[0064] The center angle is the tilt angle of the ring where the center focus of the fabric matrix is ​​located.

[0065] Compared with the prior art, the beneficial effects of the present invention are:

[0066] 1. Determine the location of the suspended material in the blast furnace (including the upper and lower parts of the suspended material). Identify the location of the suspended material and take different blasting recovery measures to accelerate the furnace condition recovery process and improve the stability and economy of the furnace condition after recovery. Identifying the location of the suspended material is a necessary condition for analyzing the cause of the suspended material and taking correct and targeted measures to adjust the furnace condition.

[0067] 2. For different suspended material locations, different furnace condition recovery methods, parameter setting rules, and coke addition methods were invented to minimize suspended material loss and improve the recovery speed of blast furnace after suspended material.

[0068] 3. Maintaining the shape of the material surface during the upper suspension process can accelerate the subsequent air supply process, reduce pig iron production loss, and reduce the possibility of secondary collapse and slippage accidents.

[0069] 4. Select different methods for reducing airflow to "settle the material" according to different suspended material locations. Based on the different characteristics of the suspended material locations, adopt corresponding airflow reduction methods to accelerate the furnace condition recovery process as much as possible and optimize the suspended material recovery process.

[0070] 5. Based on the specific collapse depth L2-L1, the weight of the net coke to be replenished is quantitatively calculated. Based on the change in furnace top temperature T2-T1, the degree of gas flow pipeline is quantitatively calculated, and the weight of net coke required for the pipeline stroke is calculated. The weight of the net coke to be replenished is calculated in a comprehensive manner, which can avoid excessive or insufficient coke addition, resulting in fuel oversupply or undersupply, and secondary fluctuations in the furnace conditions that follow.

[0071] 6. Determine the material distribution method for increasing clean coke, and innovatively differentiate between clean coke A for supplementing collapsing material and clean coke B for supplementing heat source through pipeline. The material distribution method is more scientific, effectively improves the actual effect of coke, and maximizes the effect of clean coke in supplementing blast furnace heat and improving the permeability of the material layer.

[0072] 7. Reduce the adverse effects of suspended material on blast furnace conditions and avoid long-term abnormal blast furnace conditions. Detailed Implementation

[0073] The present invention will now be described in detail, but it should be noted that the implementation of the present invention is not limited to the following embodiments.

[0074] The following embodiments are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operation processes. However, the scope of protection of the present invention is not limited to the following embodiments. Unless otherwise specified, the methods used in the following embodiments are conventional methods.

[0075]

Example 1

[0076] Taking a certain steel plant 3200m 3 Taking a blast furnace as an example, when the hot blast pressure in the blast furnace increases from 413 kPa to 417 kPa, briquettes become suspended, and the probe stops. The method for determining the location of the briquetted material suspension in the blast furnace is as follows:

[0077] Determine the position of the suspended material

[0078] Analysis of the static pressure values ​​in the blast furnace body revealed four monitoring points for static pressure. These points were located at the 10th cooling wall section and the lower part of the furnace body. At three of these monitoring points, the static pressure increased from 280 kPa to 283 kPa, exhibiting the following characteristics:

[0079] ① The static pressure of the furnace body shows a peak, with a rise rate of 0.6 kPa / s. 0.6 kPa / s > 0.5 kPa / s, and the static pressure of the furnace body rises earlier than the air pressure.

[0080] ② Both the static pressure at the top of the furnace body and the static pressure in the belly of the furnace body reached their peak values, but the peak value of the static pressure at the top of the furnace body appeared earlier than the rise time of the static pressure in the belly of the furnace body.

[0081] ③ The rate of increase of static pressure in the upper part of the furnace body is greater than the rate of increase of static pressure in the belly of the furnace. Among the two static pressure curves, the slope of the static pressure curve in the furnace body is significantly greater than that in the static pressure curve in the belly of the furnace. Alternatively, the rate of increase of pressure can be calculated by dividing the pressure increase value by the pressure increase time.

[0082] If the static pressure of the furnace body meets any one of the three characteristics, it can be determined that the suspended material is suspended from the top.

[0083] If a peak increase occurs in the static pressure of the furnace belly or the hot air pressure, with a pressure increase rate > 0.5 kPa / s, while the static pressure of the furnace body decreases or shows no significant change, it can be clearly determined that the material is suspended in the lower part of the furnace.

[0084] The treatment methods for the suspended charge area in a blast furnace are as follows:

[0085] Step 1:

[0086] Suspended material at the top, controlling wind speed and increasing coke surface shape:

[0087] After determining the location of the suspended charge, the blast furnace immediately reduced the blast furnace inlet air volume by 400 m³ using an electric blower. 3 / At min, the blast furnace blast pressure decreased from 417 kPa to 392 kPa; the current furnace top pressure is in automatic adjustment mode, with a set value of 235 kPa, and the blast furnace pressure decreased by 400 m. 3 The blast furnace inlet air volume and its top pressure setting value should be reduced by 18 kPa according to the conventional reduced air volume operation, and is set to 217 kPa; the furnace top pressure reduction value after using the air volume reduction method of this patent is only 30-80% of the conventional reduced air volume operation. Selecting a top pressure reduction coefficient of 0.5, then according to formula ①, as shown below:

[0088]

[0089] In formula ①, P2 represents the set value of the blast furnace top pressure after blast reduction, in kPa; P1 represents the set value of the blast furnace top pressure before blast reduction, in kPa. In this example, P1 = 235 kPa. 热2 This represents the hot blast pressure value after reducing the blast furnace air pressure, in kPa; P 热1 The value represents the hot blast pressure before the blast furnace blast rate is reduced, in kPa; η represents the top pressure coefficient for the suspended charge furnace condition, a dimensionless unit, with a value of 0.3 to 0.8.

[0090] According to formula ①, P2 = 235(1-0.5+0.5*392 / 417) = 227 kPa, so the furnace top pressure is set to 227 kPa.

[0091] Since the suspended material is located at the top, 1-2 batches of coke need to be added to maintain the shape of the material surface, in order to accelerate the subsequent recovery of the blast furnace condition.

[0092] The method of adding coke to maintain the shape of the material surface can be either method one or method two:

[0093] Method 1: Use single-ring fabric

[0094] The tilting angle is the weighted average of the tilting angles and the number of charging rings of all ring positions in the current charging matrix of the blast furnace, excluding the center coke charging, as shown in Table 1.

[0095] Table 1. Material distribution matrix used in the suspension of a 3200m³ blast furnace at a steel plant.

[0096]

[0097] According to the above matrix method one, the tilting angle of the single ring material feeding is: (41.8°*6+39.2°*7+36.5°*5+33.7°*4+30.8°*4) / 26=37.1°. The batch of clean coke is fed into the furnace in a single ring at a tilting angle of 37.1°.

[0098] Method 2: Using a single-ring fabric method

[0099] The tilting angle is as follows: Based on the infrared imaging of the material surface at the top of the furnace, first determine the position of the point (Q point) where the temperature value drops the most before and after the material is suspended in the circumference of the furnace throat; then calculate the tilting angle of the chute corresponding to the radius L between the position of Q point and the center of the furnace throat; finally, according to the tilting angle of the chute, the coke is distributed in a single ring on the ring where the temperature drop point is located.

[0100] The specific steps are as follows:

[0101] Infrared imaging of the blast furnace top revealed that the temperature drop was greatest at a location with a radius r = 3.6m from the center of the furnace throat, decreasing from 132℃ to 71℃. Based on the formula for the charge placement point, the result is as follows:

[0102] The distance r from point Q to the center point of the furnace throat is obtained according to the cloth landing point formula, as follows:

[0103]

[0104] In Formula ②: t is the falling time of the furnace charge after leaving the chute, in seconds; v2 is the velocity of the furnace charge when leaving the chute, in m / s; l is the effective length of the chute, in meters; α is the chute inclination angle, in degrees; and w is the angular velocity of the chute, in rad / s.

[0105]

[0106] In formula ③: v0 is the initial velocity of the furnace charge after falling into the chute, in m / s; λ is the velocity loss coefficient; v2 is the velocity of the furnace charge when leaving the chute, in m / s; g is the acceleration due to gravity, in m / s²; l is the effective length of the chute, in m; α is the chute inclination angle, in °; μ is the friction coefficient between the furnace charge and the chute; w is the angular velocity of the chute, in rad / s.

[0107]

[0108] In formula ④: v0 is the material flow velocity before falling into the chute, in m / s; F is the measured flow rate of the furnace charge at the throttle valve, in m³ / s; S is the projected area of ​​the throttle valve, in m²; l S d0 represents the perimeter of the throttle valve, in meters; d0 represents the average particle size of the furnace charge, in meters.

[0109] The tilting angle α corresponding to the landing point radius r = 3.6m was calculated to be 35°. The tilting angle of the blast furnace chute was manually set to 35°, and the clean coke was distributed into the blast furnace in a single ring to achieve precise distribution of the coke that maintains the shape of the material surface on the annular area where the temperature drop maximum point Q is located.

[0110] In this case, since the infrared imaging of the furnace top showed a significant temperature drop area, it was specifically chosen to add one batch of coke to maintain the shape of the material surface, and the second method of addition was adopted.

[0111] Step Two:

[0112] Reduce airflow and "settle material" according to the upper suspended material:

[0113] The furnace top pressure regulation was switched to manual. During non-accident shutdowns and reduced blast, the TRT bypass valve group's valve opening was set to 100%. Therefore, after reducing blast, the blast furnace TRT bypass valve group needed to be manually opened to 55%–85% of its normal opening, thus setting the valve opening to 60% to ensure a significant reduction in the actual flow velocity in all areas of the furnace during the charging process. After stopping oxygen enrichment, pulverized coal injection, and furnace top water injection according to the conventional charging procedure, the venting valve was used to reduce the air volume to 30%–0% of the full blast capacity in one go, until the stagnant probe showed signs of material collapse. After the collapse, a rapid return airflow of 200–400 m³ was initiated. 3 / min, to accelerate the air supply process and then gradually increase the air volume to restore the air volume.

[0114] Step 3:

[0115] The increase in net coke weight was determined through calculation:

[0116] The increase in net coke quantity is determined by formula ②. After the blast furnace "seat charging" blast reduction, the maximum material depth is 3. # The probe depth is 4.6m, and the material line depth before blast reduction is 1.5m. Significant pipe travel occurred during the collapse process. The highest temperature at the four furnace top points increased from 133℃ before collapse to 389℃. According to formula ②, L2 = 4.6 m; L1 = 1.5 m; T2 = 389℃; T1 = 133℃; the batch weight of coke charged into the blast furnace is 15.37 tons. Based on experience, the coke replenishment coefficients for collapse and pipe travel are a = 0.6 and b = 0.7, respectively. The formula for calculating the increase in net coke weight is as follows:

[0117]

[0118]

[0119] Calculate the required increase in net coke concentration (M). 焦 If the quantity is 75.5 tons, then the net number of coke batches is N = 75.5 / 15.37 = 4.9, rounded down to 5 batches.

[0120] N = M 焦 / m1 ⑥

[0121] Based on N=5, the net coke weight for each batch is set to M. 焦 If the weight is / N tons, then the net weight of each batch of coke is 75.5 / 5 = 15.1 tons;

[0122] The actual increase in net coke was 5 batches, each batch weighing 15.1 tons, for a total weight of 75.5 tons.

[0123] Step Four:

[0124] Determine the method of increasing the net coke concentration using the following fabric:

[0125] Calculate the added net coke weight M in formula ② 焦 Divided into two parts:

[0126] A = (L2 - L1) / 0.5 * a * m1 = 3.72 × 15.37 = 57.18 tons

[0127] B = (T2 - T1) / 150·b·m1 = 18.36 tons

[0128] The specific material distribution method for the upper suspended coke is as follows:

[0129] Upper suspension material: N A =A / m1=57.18 / 15.37=3.72, N A Take the integer part and select 4 batches; take part A and select N. A Clean coke in the blast furnace, according to the original charging matrix (Table 1), part B, N B =NN A =5-4=1 batch of clean coke is calculated by subtracting the center ring position from the matrix ring position in Table 1 (converted to Table 2); the clean coke of part B (1 batch) is distributed in the blast furnace annular zone area.

[0130] Table 2. Matrix of Net Coke Placement for Supplementary Heat Source in Pipeline Stroke of a Steel Plant's 3200m³ Blast Furnace

[0131]

[0132] If the problem is a lower suspension of material: Since N≥3, the coke can be laid in a tilted position at the center angle (10°) for 1-2 batches, and the remaining coke can be laid in the normal matrix of Table 1.

[0133] Between each batch of clean coke, 3 to 10 batches of ore are spaced out, and then the blast furnace is returned to its normal return air procedure.

[0134] This invention addresses the identification of blast furnace charge suspension points (including upper and lower suspension points), clearly defining these points and enabling targeted blasting recovery measures to accelerate furnace condition recovery and improve stability and economy after recovery. Clearly identifying the suspension point is essential for analyzing the causes of charge suspension and subsequently implementing correct and targeted furnace condition adjustments. Different furnace condition recovery methods, parameter setting rules, and coke addition methods are invented for different suspension points to minimize charge loss and improve the recovery speed after charge suspension. Maintaining the charge surface shape in upper suspension accelerates subsequent blasting, reduces pig iron production loss, and minimizes the possibility of secondary charge collapse and slippage accidents. Different blasting reduction methods are selected based on the suspension point, and corresponding blasting reduction measures are implemented according to the different characteristics of each suspension point. This method can accelerate the furnace condition recovery process as much as possible and optimize the suspended material recovery process. Based on the specific collapse depth L2-L1, the weight of the supplementary collateral coke is quantitatively calculated. Based on the furnace top temperature change T2-T1, the degree of gas flow pipeline is quantified, and the weight of collateral coke required for the pipeline stroke is calculated. The comprehensive calculation of the supplementary collateral coke weight can avoid excessive or insufficient coke addition leading to fuel overload or underload, and the resulting secondary fluctuations in furnace condition. The method of increasing collateral coke distribution is determined, innovatively differentiating between supplementary collateral coke (A) and collateral coke used for pipeline heat source replenishment (B). This more scientific distribution method effectively improves the actual effect of coke, maximizing the effect of collateral coke in supplementing blast furnace heat and improving the permeability of the material bed. It reduces the adverse effects of suspended material on blast furnace condition and avoids long-term furnace condition abnormalities.

Claims

1. A process for determining a current blast furnace operating condition as a blast furnace suspension site where a suspension phenomenon occurs, characterized in that, Comprise: 1) the following features appear more than one, for judging the position of the suspension material in the blast furnace is located in the upper part of the blast furnace, as follows: a. The static pressure of the upper part of the blast furnace appears one or more rising peaks, and the rising rate of the pressure is higher than that of the hot blast pressure, and the time of the peak is earlier than that of the hot blast pressure. b, the static pressure of the upper part of the blast furnace and the static pressure of the bosh of the blast furnace all appear peak, but the peak of the static pressure of the upper part of the blast furnace appears earlier than the static pressure of the bosh of the blast furnace rises; c, the static pressure of the upper part of the blast furnace and the static pressure of the bosh of the blast furnace all appear peak, but the static pressure of the upper part of the blast furnace rises faster than the static pressure of the bosh of the blast furnace; 2) the following features appear, for judging the position of the suspension material in the blast furnace is located in the lower part of the blast furnace, as follows: The static pressure of the bosh of the blast furnace or the hot blast pressure appears a rising peak, and the pressure rising rate is >0.5kPa / s, while the static pressure of the blast furnace decreases or has no obvious change; The processing method further comprises: S1, if it is upper suspension material, control the wind speed and increase the coke for maintaining the shape of the material surface; S2, select different ways to reduce the wind according to the different positions of the suspension material; S3, quantitatively calculate the supplementary net coke weight; S4, determine the way of increasing net coke distribution; In S1, the content of controlling the wind speed is as follows: The blast furnace inlet air volume is reduced, and the value is: The blast furnace top pressure set value is reduced with the blast volume reduction, and the top set value is reduced to The formula is as follows: ① In formula ①, represents the blast furnace top pressure set value after reducing the blast, with the unit of kPa, represents the blast furnace top pressure set value before reducing the blast, with the unit of kPa; represents the hot blast pressure value after reducing the blast of the blast furnace, with the unit of kPa; represents the hot blast pressure value before reducing the blast of the blast furnace, with the unit of kPa; represents the top pressure reduction coefficient of the suspended material furnace condition, with the unit of dimensionless, and the value is 0.3~0.

8.

2. The method of treating a high furnace suspension zone as defined in claim 1, characterized in that, In S1, the way of increasing the coke for maintaining the shape of the material surface includes way one and way two, and the contents are as follows: Way one: the net coke distribution side adopts single ring distribution, and the tilting angle of the single ring distribution is the weighted average of all ring positions in the current distribution matrix of the blast furnace except the center coke addition and the number of distribution rings; Way two: the net coke distribution side adopts single ring distribution, and the tilting angle of the single ring distribution is α: Firstly, according to the infrared imaging of the top material surface, the position of the point Q with the largest temperature drop value before and after the suspension material in the throat circular cross section is determined; The distance length r of the point Q from the center point of the throat is obtained, and the distribution point formula is as follows: ② In formula (2): is the falling time of the furnace burden after leaving the chute, in seconds, is the speed of the furnace burden when leaving the chute, in meters per second; is the effective length of the chute, in meters; is the inclination angle of the chute, in degrees; is the angular velocity of the chute, in radians per second; ③ In formula 3: is the initial velocity of the furnace charge after falling into the chute, with the unit of m / s; is the velocity loss coefficient; is the velocity of the furnace charge when leaving the chute, with the unit of m / s; is the gravitational acceleration, with the unit of ; is the effective length of the chute, with the unit of m; is the inclination angle of the chute, with the unit of °; is the friction coefficient between the furnace charge and the chute; is the angular velocity of the chute, with the unit of rad / s; ④ In formula (4): is the velocity of the material stream before falling into the chute, in m / s; is the measured flow rate of the furnace charge when passing through the throttle, in ; is the projected area of the throttle, in ; is the length of the perimeter of the throttle, in m; is the average particle size of the furnace charge, in m; The tilting angle α corresponding to the distribution point radius r of the point Q is calculated; Finally, according to the tilting angle α, the coke is single ring distributed on the ring at the position of the point Q with the largest temperature drop value.

3. The method of treating a high furnace suspension zone as defined in claim 1, wherein, In S2, during the "settling material" process, the manual opening degree of the TRT bypass valve group of the blast furnace top is reduced to maintain the blast furnace top pressure 10%-30% higher than the conventional settling material reduction wind pressure; According to the different positions of the suspension material, different settling material reduction wind ways are adopted to speed up the blast furnace back wind process, and the contents are as follows: 1) when the suspension material position is upper suspension material: The blast furnace top pressure regulation is changed to manual, and the valve opening degree is set to 55%-85% of the TRT manual valve opening degree under the non-accident shutdown and reduction wind state of the blast furnace; The air volume is reduced to 30%-80% of the full wind state by the air release valve at one time, and the process ends when the stagnant probe appears material collapse; Rapidly return air 200~400m 3 / min after the material collapse to speed up the furnace condition recovery process, then gradually increase the air volume to restore the air volume. 2) when the suspension material position is lower suspension material: The blast furnace top pressure regulation is changed to manual, and the valve opening degree is set to 40%-60% of the TRT manual valve opening degree under the non-accident shutdown and reduction wind state of the blast furnace; The air volume is reduced to 30%-80% of the full wind state by the air release valve at one time, and the process ends when the stagnant probe appears material collapse; After the material collapse, the air cannot be directly recovered, and the probe is lowered evenly without stagnation and sliding material for 5-10 minutes before gradually increasing the air volume to restore the air volume.

4. The method of treating a high furnace suspension zone as defined in claim 1, wherein, In S3, the formula for quantitatively calculating the supplementary net coke weight is as follows: ⑤ In formula (5), represents the net coke total mass that needs to be supplemented after the hanging material, with the unit of ton (t); represents the deepest material line detected by each probe after the material collapse, with the unit of meter (m); represents the normal set material line of the blast furnace, with the unit of meter (m); represents the maximum value in the blast furnace top temperature point during the blast furnace collapse process, with the unit of Celsius degree (°C); represents the maximum value in the blast furnace top temperature point before the blast furnace collapse, with the unit of Celsius degree (°C); a represents the collapse depth coke supplement coefficient, which is determined by the daily fuel ratio of the blast furnace and the coke quality, and the value range is 0.5-1.5, with the unit of dimensionless; b represents the pipeline stroke coke supplement coefficient, which is determined by the daily fuel ratio of the blast furnace and the coke quality, and the value range is 0.5-1.7, with the unit of dimensionless; represents the blast furnace charging coke batch weight before the collapse, with the unit of ton / batch; Through formula ⑤, the net coke batch number is obtained, and the formula is as follows: ⑥ In formula (6), N represents the number of net coke batches, N is an integer, and the unit is batch; the weight of each batch of net coke is set as The total weight of N batches of net coke is .

5. The method of treating a high furnace suspension zone as defined in claim 4, characterized in that, In S4, the calculation formula of the net coke is as follows: ⑦ ⑧ ⑨ In formulas ⑦-⑨, A represents the net coke of the material line of the material falling, and B represents the net coke of the pipeline stroke of the heat source; The material distribution mode for increasing the net coke has the following contents: 1) Upper material suspension, and the calculation formula is as follows: ⑩ In formula (10), NA represents the number of batches of net coke required for the collapsed material replenishing line, i.e. the number of batches or tanks of net coke required for the collapsed material replenishing line, NA is an integer, and the NA tanks of net coke for the collapsed material replenishing line are charged according to the coke ring position angle of the original charging matrix of the blast furnace, and the net coke B part of the pipeline travel heat source is charged according to the coke ring position angle of the original charging matrix of the blast furnace The batch net coke is charged according to the coke ring position angle of the original matrix of the blast furnace, and the net coke B part of the pipeline travel heat source is charged in the annular zone of the blast furnace. 2) Lower material suspension When N≥3, 1-2 batches of net coke are distributed at the center angle, and the remaining net coke is distributed according to the original distribution matrix ring position. When N<3, each batch of net coke is distributed according to the original distribution matrix ring position.

6. The method of treating a high furnace suspension zone as defined in claim 5, wherein, The center angle is the tilting angle of the ring position where the center of the distribution matrix is added with coke.

Images