Production control method and system for increasing iron and reducing zinc

Abstract

The invention provides a production control method and system for increasing iron and reducing zinc. According to the method, the design accumulation amount of the kiln slag in the water quenching pool is calculated by combining the geometrical characteristics of the kiln slag when the kiln slag is accumulated in the water quenching pool. And the residual kiln slag amount in the water quenching pool is obtained through the total amount of the kiln slag entering the water quenching pool and the taken-out amount of the kiln slag. And the volume ratio of the water quenching pool is calculated according to the residual kiln slag amount and the designed accumulation amount, and the steel smelting strategy is adjusted according to the volume ratio to control the kiln slag amount in the water quenching pool, so that the stability and safety of steel smelting are improved. According to the mode of obtaining the mathematical model used for calculating the volume ratio according to the geometrical characteristics, the parameter obtaining process is simple, the constructed mathematical model is more visual, and the method has higher practicability in the steel smelting process.

Description

Technical Field

[0001] The present application belongs to the technical field of steel smelting, and in particular, relates to a production control method and system for increasing iron and reducing zinc. Background Art

[0002] Iron-containing dust is produced during the steel smelting process. After sintering and agglomeration, the iron-containing dust can be put into the blast furnace for smelting again. However, during the smelting process, since the iron-containing dust contains a certain amount of zinc, the zinc element has a low boiling point and continuously evaporates in the blast furnace to form nodules on the furnace body inside the blast furnace, affecting the furnace condition and the life of the blast furnace.

[0003] In order to reduce the zinc content in iron-containing dust, a rotary kiln can be added during the smelting process to reduce the zinc in the iron-containing dust to gaseous metallic zinc. The metallic zinc combines with oxygen to form zinc oxide dust, which enters the dust collector and is collected. In addition, the rotary kiln also includes the process of slagging raw materials. After the solid slag is produced, it will be discharged into the water quenching pool and fished out by grab cranes and other related equipment.

[0004] The volume of the water quenching tank is limited. If too much slag is contained, it is easy to cause the slag flushing channel to be blocked, which in turn affects the slag discharge of the rotary kiln. In addition, if there is too much slag in the water quenching tank, the slag at the bottom is not easy to be picked up, and it is easy to agglomerate and accumulate, resulting in a reduction in the volume of the water quenching tank. The grab crane used to pick up slag from the water quenching tank has a heavy operating load, so it often needs to be repaired and maintained. The repair and maintenance takes a long time, which easily leads to untimely slag removal and affects the slag discharge process. Therefore, the volume ratio of the water quenching tank can be designed and tested to determine the amount of slag in the water quenching tank, and the time available for repairing the grab crane can also be calculated to improve the stability and safety of the smelting process. The detection of the volume ratio requires obtaining the amount of slag accumulated inside the water quenching tank. The detection of the volume by underwater sonar, laser modeling, underwater camera, etc. is easily affected by environmental interference, and the generated observation model is relatively complex and cannot intuitively reflect the volume ratio. Summary of the invention

[0005] The present application provides a production control method and system for increasing iron and reducing zinc, so as to solve the problem that when detecting the volume ratio of a water quenching tank, the detection equipment is easily disturbed by the environment, and the generated observation model cannot directly reflect the volume ratio of the water quenching tank.

[0006] In a first aspect, the present application provides a production control method for increasing iron and reducing zinc, which is applied to a steel smelting system, wherein the steel smelting system includes a kiln conveyor, a rotary kiln, a grab bucket, and a water quenching tank, including:

[0007] Calculate the designed accumulation amount of the slag in the water quenching tank in combination with the geometric characteristics of the slag when it is accumulated in the water quenching tank;

[0008] The current amount of remaining slag in the water quenching tank is obtained according to the total amount of slag entering the water quenching tank and the amount of slag removed from the water quenching tank; the total amount of slag is positively correlated with the difference between the total amount of raw materials transported by the kiln conveyor and the amount of unreacted raw materials; the amount of slag removed is positively correlated with the amount of slag scooped underwater by the grab bucket in the water quenching tank;

[0009] Calculating the ratio of the remaining slag amount to the designed accumulation amount to obtain the volume ratio inside the water quenching tank;

[0010] The steelmaking strategy is adjusted according to the volume ratio to control the amount of slag in the water quenching tank.

[0011] In some feasible embodiments, the method further includes:

[0012] When the kiln slag is naturally piled up, the geometric body formed between the kiln slag and the lower edge of the rotary kiln through which the slag is flushed is equivalent to the first standard geometric body;

[0013] The part of the first standard geometric body where the slag is not piled up is equivalent to the second standard geometric body;

[0014] Calculating a first volume of the first standard geometric body and a second volume of the second standard geometric body;

[0015] The difference between the first volume and the second volume is calculated to obtain a designed stacking volume.

[0016] In some feasible embodiments, the method further includes:

[0017] Calculate the theoretical slag formation ratio of kiln slag produced by the raw materials during the smelting process according to the exhaust gas composition of the raw materials;

[0018] Obtaining the total amount of raw materials transported by the kiln conveyor and the amount of unreacted raw materials;

[0019] Calculating the difference between the total amount of the raw material and the amount of the unreacted raw material;

[0020] The product of the slag formation ratio and the difference is calculated to obtain the total amount of kiln slag entering the water quenching tank.

[0021] In some feasible embodiments, the step of calculating the theoretical slag formation ratio of slag generated by the raw material during the smelting process according to the exhaust gas composition of the raw material includes:

[0022] The theoretical slag formation ratio is calculated according to the ratio of raw materials discharged in the flue gas; the ratio of raw materials discharged in the flue gas is obtained by the amount of raw materials discharged in the flue gas, the amount of raw materials entering the rotary kiln and the mass of reactants discharged in the flue gas;

[0023] Set the slag ratio correction threshold;

[0024] The theoretical slag formation ratio is corrected according to the slag formation ratio correction threshold value.

[0025] In some feasible embodiments, the step of correcting the theoretical slag formation ratio according to the slag formation ratio correction threshold value includes:

[0026] If the ratio of the slag removal amount to the designed accumulation amount is greater than or equal to the slag formation ratio correction threshold, the correction coefficient is calculated according to the average value of the theoretical value of the slag formation ratio before correction and the current slag formation ratio; the product of the correction coefficient and the theoretical value of the slag formation ratio at the next moment is the slag formation ratio correction value at the next moment;

[0027] If the ratio of the slag removal amount to the designed accumulation amount is less than the slag formation ratio correction threshold, the amount of slag that has been produced is calculated based on the theoretical slag formation ratio.

[0028] In some feasible embodiments, the method further includes:

[0029] Calculating the position of the grab bucket according to the position parameters of the grab bucket when grabbing the kiln slag;

[0030] When it is detected that the grab bucket reaches a preset position after grabbing the slag, the volume of the slag currently grabbed is obtained to obtain the current amount of slag removed.

[0031] In some feasible embodiments, the preset position is located below the water surface of the water quenching pool; the distance between the top of the grab bucket and the water surface of the water quenching pool is a first preset distance, and the distance between the bottom of the grab bucket and the top of the accumulated slag is a second preset distance; the first preset distance and the second preset distance are both greater than 0.

[0032] In some feasible embodiments, the adjusting of the steel smelting strategy according to the volume ratio includes:

[0033] Set the volume ratio threshold;

[0034] If the volume ratio is less than the volume ratio threshold, the input amount of raw materials is increased, and / or the grab bucket is controlled to reduce the frequency of scooping up the kiln slag;

[0035] If the volume ratio is greater than or equal to the volume ratio, the input amount of raw materials is reduced, and / or the grab bucket is controlled to increase the frequency of scooping up the kiln slag.

[0036] In some feasible embodiments, the method further includes:

[0037] The remaining allowable time is calculated according to the designed accumulation amount of the water quenching tank, the current volume ratio, the remaining allowable capacity of the water quenching tank and the average instantaneous value of the weight of the raw materials on the kiln conveyor; the remaining allowable capacity includes the remaining allowable volume and remaining allowable mass of the kiln slag that the water quenching tank can still accommodate; the remaining allowable time is the time required for the kiln slag capacity in the current water quenching tank to reach the designed accumulation amount;

[0038] If the remaining allowed time is greater than the equipment maintenance time, the control performs equipment maintenance on the equipment carrying the grab;

[0039] If the remaining allowed time is less than the equipment maintenance time, the input amount of raw materials is reduced, or the grab bucket is controlled to increase the frequency of scooping slag to reduce the volume ratio of the water quenching tank.

[0040] In a second aspect, the present application provides a production control system for increasing iron and reducing zinc, which is applied to a steel smelting process, wherein the mechanism used in the steel smelting process includes a kiln conveyor belt, a rotary kiln, a grab bucket, and a water quenching tank, including: a simulator and a processor;

[0041] The simulator is used to calculate the designed accumulation amount of the slag in the water quenching tank in combination with the geometric characteristics of the slag when it is accumulated in the water quenching tank;

[0042] The processor is used to obtain the current amount of remaining slag in the water quenching tank according to the total amount of slag entering the water quenching tank and the amount of slag removed from the water quenching tank; the total amount of slag is positively correlated with the difference between the total amount of raw materials transported by the kiln conveyor and the amount of unreacted raw materials; the amount of slag removed is positively correlated with the amount of slag scooped underwater by the grab bucket in the water quenching tank;

[0043] The processor is also used to calculate the ratio of the remaining slag amount to the designed accumulation amount to obtain the volume ratio inside the water quenching tank;

[0044] The processor is also used to adjust the steel smelting strategy according to the volume ratio to control the amount of slag in the water quenching tank.

[0045] It can be seen from the above technical content that the present application provides a production control method and system for increasing iron and reducing zinc. The method calculates the designed accumulation amount of slag in the water quenching pool by combining the geometric characteristics of the slag when it is accumulated in the water quenching pool. And the remaining slag amount in the water quenching pool is obtained by the total amount of slag entering the water quenching pool and the amount of slag taken out. The volume ratio of the water quenching pool is calculated according to the remaining slag amount and the designed accumulation amount, and the steel smelting strategy is adjusted according to the volume ratio to control the amount of slag in the water quenching pool, so as to improve the stability and safety of steel smelting. According to the method of obtaining a mathematical model for calculating the volume ratio based on geometric characteristics, the process of obtaining parameters is simple, the constructed mathematical model is more intuitive, and it is more practical in the process of steel smelting. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the embodiments are briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0047] Figure 1 A schematic diagram of a steel smelting system provided in an embodiment of the present application;

[0048] Figure 2 A schematic diagram of a method for controlling the amount of slag in a water quenching tank in a steel smelting system provided in an embodiment of the present application;

[0049] Figure 3 An equivalent schematic diagram of slag accumulation provided in an embodiment of the present application;

[0050] Figure 4 A schematic diagram of the force acting on the grab bucket under water provided in an embodiment of the present application;

[0051] Figure 5 A schematic diagram of preset position parameters provided in an embodiment of the present application. DETAILED DESCRIPTION

[0052] The following embodiments are described in detail, and examples thereof are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following embodiments do not represent all implementations consistent with the present application. They are only examples of systems and methods consistent with some aspects of the present application as detailed in the claims.

[0053] The water quenching tank can receive the solid slag discharged from the rotary kiln. It is an important part of the "iron increase and zinc reduction" of raw materials in the steel smelting process. The iron increase and zinc reduction can reduce the zinc content entering the blast furnace. After the solid slag is discharged into the water quenching tank, the grab crane and other related mechanical equipment can be operated to pick up the slag. After the slag is discharged into the water quenching tank, it accumulates in a certain geometric shape. As the accumulation amount increases, the distance between the slag and the slag discharge channel outlet of the water quenching tank becomes closer, which can easily lead to outlet congestion, and then the slag cannot be discharged, affecting the normal operation of the production line. In addition, the slag is continuously discharged into the water quenching tank during the operation of the production line. Therefore, too much slag accumulated in the water quenching tank can easily make the bottom slag difficult to be picked up, and then agglomerate and accumulate, affecting the volume of the water quenching tank.

[0054] As shown in the formula, the volume ratio of the water quenching tank refers to the ratio of the amount of slag currently contained in the water quenching tank to the maximum amount of slag that can be contained.

[0055]

[0056] Among them, V t is the amount of slag accumulated in the water quenching pool at time t, V 0 is the designed accumulation amount of kiln slag in the water quenching tank, η t is the volume ratio of the water quenching tank. Therefore, in order to improve the stability and safety of the production line during operation, the volume ratio of the water quenching tank can be used to detect the amount of slag accumulation inside the water quenching tank, and then adjust the smelting strategy on the production line. However, when detecting the amount of slag accumulation in the water quenching tank, underwater cameras, underwater sonar and other detection methods are easily affected by environmental interference, and the equipment is easily corroded, and needs to be replaced frequently, resulting in increased costs. The detection method of 3D laser scanning modeling generates a more complex observation model that is not easy for operators to understand, making it difficult to make timely judgments on the production form based on the current model.

[0057] In view of the above problems, if Figure 1 and Figure 2 As shown, the present application provides a production control method for increasing iron and reducing zinc, which is applied to a steel smelting system, wherein the steel smelting system includes a kiln conveyor, a rotary kiln, a grab bucket, and a water quenching tank, and the method includes:

[0058] S100: Calculating the designed accumulation amount of the slag in the water quenching tank in combination with the geometric characteristics of the slag when it is accumulated in the water quenching tank;

[0059] The designed accumulation volume is the maximum amount of slag that can be accommodated in the water quenching pool, which can include the volume occupied by the slag in the water quenching pool and the weight of the slag. Among them, the volume occupied by the slag can more intuitively reflect the relationship between the slag and the outlet of the slag flushing channel of the rotary kiln, and form a volume ratio with the current amount of slag in the water quenching pool, so as to adjust the smelting strategy by detecting the volume ratio.

[0060] When the slag is deposited in the water quenching tank, it will be deposited in a similar geometric shape due to its own density, gravity, buoyancy and other factors. Therefore, the designed deposit volume can be calculated by geometric analysis based on the geometric characteristics of the slag when it is deposited. For example, in some embodiments, the slag is deposited in a shape similar to a cone. The maximum bottom area and height of the cone can be obtained by combining multiple factors such as the outlet of the slag discharge channel and the scooping depth of the grab bucket, and the volume of the cone can be calculated as the designed deposit volume.

[0061] Describing the amount of slag accumulation with geometric characteristics can reduce the difficulty of constructing a mathematical model of the water quenching pool volume ratio. It also improves the practicality of the constructed mathematical model, making it easier to understand and adjust the smelting strategy based on the constructed mathematical model to improve the stability and safety of the production line.

[0062] In some embodiments, the method for obtaining the designed stacking volume includes:

[0063] When the kiln slag is naturally piled up, the geometric body formed between the kiln slag and the lower edge of the rotary kiln through which the slag is flushed is equivalent to the first standard geometric body;

[0064] The part of the first standard geometric body where the slag is not piled up is equivalent to the second standard geometric body;

[0065] Calculating a first volume of the first standard geometric body and a second volume of the second standard geometric body;

[0066] The difference between the first volume and the second volume is calculated to obtain a designed stacking volume.

[0067] like Figure 3 As shown, when the kiln slag is accumulated in the water quenching pool, its natural accumulation state is approximately a missing corner cone. In order to prevent the outlet of the rotary kiln's slag flushing channel from being blocked, when the height of the missing part of the missing corner cone is set to be consistent with the lower edge of the slag flushing channel, the corresponding natural accumulation state is the designed accumulation amount. The volume of the missing corner cone can be obtained by subtracting the volume of the complete cone from the volume of the missing part, and the missing part as a whole can be approximately regarded as a triangular cone. That is, the first standard geometric body is a cone, and the second standard geometric body is a triangular cone. By calculating the volume difference between the cone and the triangular cone, the designed accumulation amount can be obtained.

[0068] The formula for calculating the cone is as follows:

[0069]

[0070]

[0071]

[0072] Where D is the distance between the slag flushing channel and the bottom of the water quenching pool; W is the design width of the water quenching pool; A is the repose angle of the slag, that is, the minimum angle between the free surface and the horizontal plane when the free surface of the powder accumulation body is in the ultimate state of equilibrium.

[0073] The formula for calculating the volume of a triangular pyramid is as follows:

[0074] AC=2*O′C=2*D*cotA

[0075] BO′=D*cotA

[0076]

[0077]

[0078] Among them, O′O, O′C, BO′, and AC can all be measured values ​​obtained according to actual stacking conditions, so as to be used to calculate the volume of the missing part.

[0079] After calculating the volume of the cone and the missing part, we can call the formula:

[0080] V 0 =V 锥 -V 缺

[0081] Among them, V 锥 is the volume of the cone, V 缺 It is the volume of the missing part of the cone. The designed stacking volume can be obtained by subtracting the volume of the cone from the volume of the triangular pyramid.

[0082] In the process of obtaining the designed accumulation volume through geometric features, it is only necessary to measure the length and height inside the water quenching tank and calculate it in combination with the size design parameters of the water quenching tank. The operation is simple and there is no need to call too many equipments, which reduces the difficulty of obtaining the designed accumulation volume.

[0083] S200: obtaining a current amount of remaining slag in the water quenching tank according to a total amount of slag entering the water quenching tank and an amount of slag removed from the water quenching tank;

[0084] The total amount of slag is positively correlated with the difference between the total amount of raw materials transported by the kiln conveyor and the amount of unreacted raw materials. During the transportation of raw materials, the raw materials are first placed on the kiln conveyor and transported to the rotary kiln by the kiln conveyor. Therefore, the total amount of raw materials includes the raw materials participating in the chemical reaction in the rotary kiln and the raw materials to be transported / reacted on the kiln conveyor. The slag is produced by the chemical changes of the raw materials in the rotary kiln, that is, the more raw materials participating in the reaction, the more slag there is. The total amount of raw materials participating in the reaction can be obtained by subtracting the total amount of raw materials input from the raw materials to be reacted on the kiln conveyor.

[0085] The slag removal amount is positively correlated with the amount of slag removed by the grab bucket underwater in the water quenching tank. The slag removal amount is the total amount of slag removed at the current moment. When the grab bucket removes the slag in the water quenching tank, it can only remove a certain amount of slag each time. When the same grab bucket is used to remove slag, the amount of slag removed each time will not change significantly. Therefore, the more times the grab bucket is removed, the more slag will be removed.

[0086] Based on the above characteristics, the remaining slag amount can be obtained by the total amount of slag entering the water quenching tank and the amount of slag removed from the water quenching tank. The remaining slag amount is the amount of slag in the current water quenching tank. Among them, the method for calculating the total amount of slag entering the water quenching tank includes:

[0087] Calculate the theoretical slag formation ratio of kiln slag produced by the raw materials during the smelting process according to the exhaust gas composition of the raw materials;

[0088] Obtaining the total amount of raw materials transported by the kiln conveyor and the amount of unreacted raw materials;

[0089] Calculating the difference between the total amount of the raw material and the amount of the unreacted raw material;

[0090] The product of the slag formation ratio and the difference is calculated to obtain the total amount of kiln slag entering the water quenching tank.

[0091] In the process of steel smelting, the slag formation ratio refers to the ratio of the mass of the raw material forming slag to the mass of the raw material before entering the rotary kiln. Slag is the product generated by the raw material during the smelting process, but because the composition of slag is relatively complex and it is not easy to extract after being discharged into the water quenching tank, it is not appropriate to calculate the total amount of slag by combining the mass of the components in the slag with the reaction equation. However, during the reaction of the raw material, part of the redundant product is slag, which is discharged into the water quenching tank; the other part of the redundant product is discharged with the flue gas. Therefore, based on the collected flue gas, the mass of each element in the flue gas can be extracted, and then the mass of the raw material discharged through the flue gas after the reaction can be obtained.

[0092] Therefore, the theoretical slag formation ratio of kiln slag can be:

[0093] k 1 =1-k 烟

[0094] Among them, k 1 is the theoretically calculated slag ratio.

[0095] The total amount of raw materials refers to the total amount of raw materials input at the current moment, and the amount of unreacted raw materials refers to the material inventory in the slag-forming process, that is, the raw materials that are being transported on the kiln conveyor and have not yet entered the rotary kiln. Because the process from the raw materials entering the rotary kiln to the execution of the slag-forming process is a continuous process, the amount of raw materials that have participated in the slag-forming process up to the current moment can be obtained by subtracting the total amount of raw materials input from the current amount of unreacted raw materials. Furthermore, the total amount of kiln slag generated can be obtained by comparing the amount of raw materials participating in the slag-forming process with the theoretical slag-forming ratio.

[0096] The total amount of kiln slag generated is calculated according to the formula:

[0097] M 产 =(M 入窑胶带机 -C 成渣 )*k 1

[0098] Among them, M 产 M is the total amount of slag discharged into the water quenching tank by time t; 入窑胶带机 C is the total amount of material transported by the kiln conveyor until time t; 成渣 It is the material inventory in the slag forming process.

[0099] In some embodiments, after the raw materials enter the rotary kiln, the flue gas generated includes elements that can form gaseous state after combustion, such as carbon, zinc, and water. Therefore, by collecting these elements in the flue gas, the mass of these gaseous elements formed by the raw materials can be calculated, and then the mass of solid slag formed by the raw materials can also be calculated. That is, according to the flue gas exhaust components of the raw materials, the theoretical slag formation ratio of the slag generated by the raw materials during the smelting process is calculated, including:

[0100] The theoretical slag formation ratio is calculated according to the ratio of raw materials discharged in the flue gas; the ratio of raw materials discharged in the flue gas is obtained by the amount of raw materials discharged in the flue gas, the amount of raw materials entering the rotary kiln and the mass of reactants discharged in the flue gas;

[0101] Set the slag ratio correction threshold;

[0102] The theoretical slag formation ratio is corrected according to the slag formation ratio correction threshold value.

[0103] As shown in the above formula, the theoretical slag ratio can be calculated by finding the ratio of raw materials discharged from the flue gas. The ratio of raw materials discharged from the flue gas can be obtained from the mass of discharged carbon, water, dust and zinc, as shown in the formula:

[0104] m 烟 =m 烟·c +m 烟·H2O +m 烟·dust +m 烟·Zn

[0105]

[0106] m 烟·H2O =v 烟 *(H 2 O) 烟 %

[0107] m 烟·dust =v 烟 *(dust) 烟 %

[0108] m 烟·Zn =m 料 *(Zn) 料 %

[0109] Among them, m 烟 is the amount of raw material discharged from the flue gas; m 料 is the amount of raw materials entering the rotary kiln; m smoke·c, m 烟·dust 、m 烟·Zn are the components of the raw materials discharged from the flue gas (C, H 2 0. The amount of dust (dust), Zn); C 式量 , C, CO, and CO 2 The chemical molecular formula weight; v 烟 is the amount of exhaust gas; (co) 烟 %、(co 2 ) 烟 %)、(H 2 O) 烟 %、(dust) 烟 % is CO, CO in flue gas 2 , H 2 O, dust content; (Zn) 料 % is the Zn content in the raw material. 料 is the mass of raw materials reacted.

[0110] By summing up the various components of the raw materials discharged from the flue gas, we can get the amount of raw materials discharged from the flue gas, that is, m 烟 And, the proportion of raw materials discharged from flue gas can be further obtained:

[0111]

[0112] Among them, k 烟 It is the proportion of raw materials discharged from the flue gas.

[0113] According to the ratio of raw materials discharged from the flue gas, the theoretical slag ratio can be obtained:

[0114] k 1 =1-k 烟

[0115] Among them, k 1 is the theoretically calculated slag ratio.

[0116] The reaction of raw materials in the rotary kiln will be affected by environmental factors such as temperature, so the material composition in the flue gas will change as the reaction proceeds. Therefore, relying solely on the theoretical slag ratio to calculate the amount of generated slag will result in a large error. Therefore, it is necessary to dynamically adjust the theoretical slag ratio according to the reaction conditions (the amount of raw materials input, the amount of slag removed, and the amount of stored slag) to improve the accuracy of the slag ratio, thereby obtaining a more accurate amount of generated slag and improving the accuracy of the volume ratio.

[0117] In some embodiments, the production time is short, the amount of raw materials input, the amount of slag removed, and the amount of stored slag are all small, so the total amount of kiln slag generated can be calculated using the theoretical slag formation ratio. In other embodiments, the production time is long, the amount of raw materials input, the amount of slag removed, and the amount of stored slag are all large after the cumulative values ​​are large, and the total amount of kiln slag generated by the practical theoretical slag formation ratio calculation will have a large error, so the theoretical slag formation ratio needs to be corrected to improve the accuracy of the calculated total amount of kiln slag generated. The slag formation ratio correction threshold can be used to trigger the step of slag formation ratio correction. By setting the slag formation ratio correction threshold, the theoretical slag formation ratio can be corrected in time according to the reaction situation after the production progress reaches a certain level, so as to improve the calculation accuracy of the total amount of kiln slag generated, thereby improving the accuracy of the volume ratio.

[0118] According to the definition of slag formation ratio and the above theoretical slag formation ratio calculation formula, we can also get the formula:

[0119]

[0120] Where, k' is the correction value of slag formation ratio; M 捞渣 M is the total weight of the slag removed from the water quenching tank; 存渣 It is the weight of the residual slag in the water quenching tank.

[0121] Therefore, according to M 捞渣 With M 存渣 The slag formation ratio correction threshold is formulated based on the relationship between the slag formation ratio and the slag formation ratio correction threshold, and then the step of determining whether to perform the slag formation ratio correction is performed according to the slag formation ratio correction threshold. That is, the step of correcting the theoretical slag formation ratio according to the slag formation ratio correction threshold includes:

[0122] If the ratio of the slag removal amount to the designed accumulation amount is greater than or equal to the slag formation ratio correction threshold, the correction coefficient is calculated according to the average value of the theoretical value of the slag formation ratio before correction and the current slag formation ratio;

[0123] According to the above formula, as the production time increases, M 捞渣 The value will be much larger than M 存渣 , M 存渣 The maximum value of is the weight of the volume corresponding to the designed accumulation amount. However, when the production time increases to a certain extent, M can be ignored when calculating the correction value of the slag formation ratio. 存渣 Therefore, the slag ratio correction threshold can be set:

[0124]

[0125] Among them, M v0 is the weight of the kiln slag reaching the designed accumulation amount; β is the slag formation ratio correction threshold.

[0126] In some embodiments, β is at least 100, so that the slag ratio correction threshold can clearly distinguish whether the theoretical slag ratio needs to be corrected. v0 Relative to M 捞渣 It can be ignored, so the total amount of kiln slag generated by calculating the theoretical slag ratio will have a significant error. Therefore, when it is detected that the slag ratio correction threshold β is at least 100, the theoretical slag ratio needs to be corrected according to the correction coefficient.

[0127] The correction factor can be obtained according to the following formula:

[0128]

[0129] ˉ

[0130] Among them, k 1 is the average value of the theoretically calculated slag ratio when making corrections; α is the correction coefficient; k' is the slag ratio correction value. k' is M 捞渣 The value is much larger than M 存渣 The slag formation ratio correction value is calculated in real time based on the slag removal amount, slag storage amount (equivalent to the designed storage amount) and the amount of reacted raw materials. Therefore, its accuracy is higher than the theoretical slag formation ratio that does not consider the relationship between the slag removal amount and the slag storage amount. Combined with the above formula, k' can also be obtained according to the following formula:

[0131]

[0132]

[0133] Among them, ρ 渣 is the density of kiln slag; V 总渣 is the total volume of slag removed from the water quenching tank; ρ 水 is the density of water; m is the weight value obtained by the weighing sensor; m 斗 Indicates the quality of the grab; is time T 成渣 The average value of the instantaneous value of the weight of the material on the kiln conveyor; T 成渣 The time required for the slag forming process.

[0134] The slag formation ratio correction value takes into account the quantitative relationship between the slag removal amount and the stored slag amount, and is calculated based on parameters such as the actual kiln slag amount and the slag removal amount, which is more in line with the actual production situation. It is understandable that the theoretical value of the slag formation ratio will change significantly with the increase of production time, but after the slag formation ratio correction threshold is triggered during the production process, the slag removal amount is much greater than the stored slag amount, and the accuracy of the slag formation ratio correction value will always be closer to the actual production situation than the slag formation ratio theoretical value. The correction coefficient at the moment of triggering the slag formation ratio correction threshold can be used continuously after the slag formation ratio correction threshold is triggered, that is, the correction coefficient can still represent the numerical relationship between the theoretical value and the correction value of the slag formation ratio when the two change.

[0135] When the production time reaches a certain length, the average value of the theoretical slag ratio during this production time can be used to represent the theoretical slag ratio at the current moment; the product of the correction coefficient and the theoretical value of the slag ratio at the current moment is the corrected slag ratio at the current moment.

[0136] If the ratio of the slag removal amount to the designed accumulation amount is less than the slag formation ratio correction threshold, the amount of slag that has been produced is calculated based on the theoretical slag formation ratio.

[0137] In some embodiments, if the slag formation ratio correction threshold is not triggered, the total amount of kiln slag generated can be calculated using the slag formation ratio theoretical value, and whether the slag formation ratio correction threshold is triggered is continuously detected. After the slag formation ratio correction threshold is triggered, the slag formation ratio theoretical value is corrected.

[0138] The slag ratio correction threshold is set according to the quantitative relationship between the slag removal amount and the stored slag amount, which is closer to the actual production situation. The slag ratio correction threshold is used to divide the total amount of generated slag into two situations. Before the slag ratio correction threshold is triggered, the total amount of slag generated is calculated by the theoretical slag ratio; after the slag ratio correction threshold is triggered, the total amount of slag generated is calculated according to the theoretical slag ratio at the current moment and the correction coefficient. Using different slag ratios according to changes in production conditions is conducive to improving the accuracy of calculating the total amount of generated slag, and then improving the accuracy of volume ratio calculation.

[0139] When calculating the slag removal amount, it is necessary to accumulate the total amount of kiln slag removed by the grab bucket each time. The method includes:

[0140] Calculating the position of the grab bucket according to the position parameters of the grab bucket when grabbing the kiln slag;

[0141] When it is detected that the grab bucket reaches a preset position after grabbing the slag, the volume of the slag currently grabbed is obtained to obtain the current amount of slag removed.

[0142] The weight of the slag picked up by the grab bucket is roughly the same each time. In order to ensure the picking efficiency, reduce the number of times the grab bucket is used and protect the grab bucket and related equipment, the grab bucket is used to reach the full grab rate each time. The total amount of slag picked up can be obtained by accumulating the weight of the slag picked up by the grab bucket each time. When the grab bucket moves the picked up slag to the location where the slag is stored, it is not conducive to measuring the weight of the picked up slag, which is easy to reduce the calculation efficiency, and then cause the volume ratio detection system to respond slowly. Therefore, when the grab bucket reaches the full grab rate, the slag mass can be measured by the weighing sensor set on the grab bucket.

[0143] In some embodiments, the grab bucket will also take out some water in the water quenching tank when taking out the slag, so the weight measured by the weighing sensor is too large. In order to offset the weight of this part of water, the preset position can be set below the water surface of the water quenching tank, that is, after the grab bucket takes out the slag and before it comes out of the water, the weighing measurement of the slag is triggered by setting the preset position.

[0144] like Figure 4 As shown in the figure, the force of the grab bucket under water can be expressed as:

[0145] F 拉 +F 浮 =G 斗 +G 渣

[0146] Right now:

[0147] mg+ρ 水 V 渣 =m 斗 g+m 渣 g=m 斗 g+ρ 渣 V 渣

[0148] Then the amount of slag removed from the water quenching tank can be obtained:

[0149]

[0150] Among them, F 拉 —Grab bucket wire rope tension, F 拉 =mg, m is the weight value obtained by the weighing sensor, g is the acceleration of gravity; Ffloat - the buoyancy of the slag under water, F 浮 =ρ 水 V 渣 , ρ 水 is the density of water, V 渣 is the volume of kiln slag; G 斗 — Gravity of the grab bucket, G 斗 =m 斗 g,m 斗 Indicates the quality of the grab; G 渣is the gravity of the grab bucket, G 渣 =m 渣 g=ρ 渣 V 渣 g,m 渣 Indicates the mass of kiln slag, ρ 渣 is the density of kiln slag; V 渣 The volume of slag taken out by the grab bucket each time. After obtaining the current volume of slag taken out, the total volume of slag taken out can be obtained by accumulating the number of times the slag has been taken out up to the current moment.

[0151] The key to the process of obtaining the volume of slag is to test the volume of the slag when the grab is below the water surface of the water quenching tank. That is, the volume and quality of the slag scooped by the grab are tested only when the grab is at the preset position. Therefore, by detecting whether the grab has reached the preset position, it can be determined whether to test the volume and quality of the slag scooped.

[0152] When judging whether the grab bucket has reached the preset position, a comprehensive judgment can be made based on the top and bottom of the grab bucket, the water surface height of the water quenching pool, and the height of the natural accumulation of slag, that is, the preset position is below the water surface of the water quenching pool; the distance between the top of the grab bucket and the water surface of the water quenching pool is a first preset distance, and the distance between the bottom of the grab bucket and the top of the accumulated slag is a second preset distance; the first preset distance and the second preset distance are both greater than 0.

[0153] In some embodiments, assuming that the height of the accumulated slag is H and the height of the grab is H 斗 , the depth of water in the water quenching tank is H 水 , the first preset distance is H 1 , the second preset distance is H 2 .like Figure 5 As shown, H, H 斗 , H 水 , H 1 , H 2 The relationship between them conforms to the formula:

[0154] H=H 水 -H 斗 -H 1 -H 2

[0155] Among them, the depth of water and the height of the grab are both known values. The depth of water can be measured in advance, and the height of the grab can be obtained according to the type of grab used. The first preset distance and the second preset distance are preset distances. The first preset distance can be 0.5m, and the second preset distance can be 1m. The first preset distance and the second preset distance are used to jointly limit the preset position, which can avoid the path of the slag falling from the slag flushing channel into the water quenching pool when the grab reaches the full grab rate and stays underwater waiting for slag detection, so as to prevent the slag flushed out of the slag flushing channel from affecting the detection accuracy of the slag picked up by the grab. At the same time, it can ensure that the picked up slag is all underwater, so the mass of the water picked up in the grab can be offset by model calculation, so that only the mass of the picked up slag is obtained.

[0156] It is understandable that in H 斗 , H 水 , H 1 , H 2 When both are known or pre-set, H is also a fixed value or a range value that allows small fluctuations. 斗 , H 水 , H 1 , H 2 The calculated H is used to determine whether the grab bucket has reached the preset position.

[0157] Through H, H 斗 , H 水 , H 1 , H 2 These parameters, which are relatively easy to obtain, limit the preset position, thereby ensuring that after the grab bucket has scooped up the kiln slag, a mathematical model can be established underwater to calculate the amount of kiln slag scooped up. The process of obtaining parameters is relatively easy, which reduces the difficulty of calculating the amount of kiln slag scooped up each time. At the same time, calculating the amount of kiln slag scooped up in the grab bucket underwater can reduce the influence of the water scooped up when scooping up the kiln slag on the calculation of the kiln slag amount, and improve the calculation accuracy of the amount of kiln slag scooped up each time.

[0158] S300: Calculating the ratio of the remaining slag amount to the designed accumulation amount to obtain the volume ratio inside the water quenching tank;

[0159] According to the definition of the water quenching tank volume ratio, the ratio of the remaining slag volume to the designed accumulation volume can be obtained, and the ratio is the volume ratio inside the water quenching tank. According to the volume ratio, the steelmaking strategy can be adjusted to ensure production efficiency and improve the stability and safety of the steelmaking system.

[0160] S400: adjusting the steelmaking strategy according to the volume ratio to control the amount of slag in the water quenching tank.

[0161] By detecting the volume ratio, the current slag accumulation in the water quenching tank can be detected. For example, the production efficiency of the current production line can be obtained based on the internal slag accumulation. It can also be used to calculate the time when the slag in the water quenching tank reaches the designed accumulation amount, so as to perform equipment maintenance based on the time difference.

[0162] In some embodiments, when adjusting the steelmaking strategy according to the volume ratio, it includes:

[0163] Set the volume ratio threshold;

[0164] If the volume ratio is less than the volume ratio threshold, the input amount of raw materials is increased, and / or the grab bucket is controlled to reduce the frequency of scooping up the kiln slag;

[0165] If the volume ratio is greater than or equal to the volume ratio, the input amount of raw materials is reduced, and / or the grab bucket is controlled to increase the frequency of scooping up the kiln slag.

[0166] The volume ratio threshold can be a specific value or a range value including an upper limit and a lower limit. The role of the volume ratio threshold is not limited to adjusting the amount of slag in the water quenching tank. It is also possible to adjust the raw material input and equipment call according to whether the current amount of slag in the water quenching tank reaches the volume ratio threshold.

[0167] For example, when it is detected that the current volume ratio of the water quenching tank exceeds the upper limit of the volume ratio threshold, it can be judged that the amount of slag currently generated is too much, and then it can be judged that the amount of raw materials input is too much. The amount of slag generated can be reduced by reducing the amount of raw materials input, and then the volume ratio can be restored to a normal level. In some embodiments, the increase in the amount of raw materials input is to increase the output, so it is not appropriate to reduce the volume ratio by reducing the amount of raw materials input. The amount of slag in the water quenching tank can be reduced by increasing the frequency of grabbing, thereby reducing the volume ratio.

[0168] For another example, when it is detected that the current volume ratio of the water quenching tank is lower than the lower limit of the volume ratio threshold, it can be judged that the amount of slag currently generated is too small, and then it can be judged that the amount of raw materials input is too small, which is easy to reduce production efficiency. Therefore, the volume ratio can be increased by increasing the amount of raw materials input to achieve the effect of improving production efficiency. In some embodiments, the frequency of grabbing slag can also be reduced to protect the equipment and extend the service life of the grab and related equipment.

[0169] In some embodiments, the method for adjusting the steelmaking strategy according to the volume ratio further includes:

[0170] Calculating the remaining allowable time according to the designed accumulation amount of the water quenching tank, the current volume ratio, the remaining allowable capacity of the water quenching tank and the average instantaneous value of the weight of the raw materials on the kiln conveyor belt;

[0171] If the remaining allowed time is greater than the equipment maintenance time, performing equipment maintenance on the equipment carrying the grab;

[0172] If the remaining allowed time is less than the equipment maintenance time, the input amount of raw materials is reduced, or the grab bucket is controlled to increase the frequency of scooping slag to reduce the volume ratio of the water quenching tank.

[0173] The remaining allowable capacity includes the remaining allowable volume and remaining allowable mass of the slag that the water quenching tank can accommodate; the remaining allowable time is the time required for the slag capacity in the current water quenching tank to reach the designed accumulation amount.

[0174] The remaining allowable time refers to the time during which the production line can operate normally without removing the slag from the water quenching tank. Therefore, the remaining allowable time can also be the time required for the slag in the water quenching tank to reach the designed accumulation volume, which can be calculated according to the following formula:

[0175] V x =(1-η t )*V 0

[0176]

[0177]

[0178] Where x is the time required for the slag in the water quenching pool to reach the designed accumulation amount; V x M is the volume of slag that can be accommodated in the water quenching pool; x The water quenching tank can also accommodate the mass of kiln slag; The average value of the instantaneous value of the weight of the material on the kiln conveyor belt.

[0179] According to the above formula, the expression of the remaining allowed time x can be obtained:

[0180]

[0181] Mechanical equipment equipped with a grab bucket needs to perform multiple maintenance steps such as replacing the reducer, wire rope pulley block, adding lubricating oil, etc. during maintenance, so it may take a long time. However, after calculating the remaining allowable time based on the volume ratio, a strategy for equipment maintenance can be formulated based on the remaining allowable time. In some embodiments, if the remaining allowable time is greater than the equipment maintenance time, the equipment equipped with the grab bucket can be fully maintained. In other embodiments, if the remaining allowable time is less than the equipment maintenance time, it means that the current volume in the water quenching tank is relatively high, and the amount of accumulated slag is large, and the volume ratio needs to be reduced as soon as possible. Therefore, the volume ratio can be reduced by reducing the input of raw materials or increasing the frequency of grab bucket scooping to increase the remaining allowable time for equipment maintenance. It can be understood that in the case of tight production demand, the equipment can also be partially maintained according to the remaining allowable time to improve time utilization.

[0182] The present application also provides a production control system for increasing iron and reducing zinc, which is applied to the steel smelting process. The mechanism used in the steel smelting process includes a kiln conveyor belt, a rotary kiln, a grab bucket and a water quenching tank, including: a simulator and a processor;

[0183] The simulator is used to calculate the designed accumulation amount of the slag in the water quenching tank in combination with the geometric characteristics of the slag when it is accumulated in the water quenching tank;

[0184] The processor is used to obtain the current amount of remaining slag in the water quenching tank according to the total amount of slag entering the water quenching tank and the amount of slag removed from the water quenching tank; the total amount of slag is positively correlated with the difference between the total amount of raw materials transported by the kiln conveyor and the amount of unreacted raw materials; the amount of slag removed is positively correlated with the amount of slag scooped underwater by the grab bucket in the water quenching tank;

[0185] The processor is also used to calculate the ratio of the remaining slag amount to the designed accumulation amount to obtain the volume ratio inside the water quenching tank;

[0186] The processor is also used to adjust the steel smelting strategy according to the volume ratio to control the amount of slag in the water quenching tank.

[0187] It can be seen from the above technical content that the present application provides a production control method and system for increasing iron and reducing zinc. The method calculates the designed accumulation amount of slag in the water quenching pool by combining the geometric characteristics of the slag when it is accumulated in the water quenching pool. And the remaining slag amount in the water quenching pool is obtained by the total amount of slag entering the water quenching pool and the amount of slag taken out. The volume ratio of the water quenching pool is calculated according to the remaining slag amount and the designed accumulation amount, and the steel smelting strategy is adjusted according to the volume ratio to control the amount of slag in the water quenching pool, so as to improve the stability and safety of steel smelting. According to the method of obtaining a mathematical model for calculating the volume ratio based on geometric characteristics, the process of obtaining parameters is simple, the constructed mathematical model is more intuitive, and it is more practical in the process of steel smelting.

[0188] Similar parts between the embodiments provided in this application can be referenced to each other. The specific implementation methods provided above are only a few examples under the general concept of this application and do not constitute a limitation on the protection scope of this application. For those skilled in the art, any other implementation methods expanded based on the scheme of this application without creative work belong to the protection scope of this application.

Claims

1. A production control method for increasing iron and reducing zinc, applied to a steel smelting system, wherein the steel smelting system comprises a kiln conveyor, a rotary kiln, a grab bucket and a water quenching tank, characterized in that: include: Calculate the designed accumulation amount of the slag in the water quenching tank in combination with the geometric characteristics of the slag when it is accumulated in the water quenching tank; The current amount of remaining slag in the water quenching tank is obtained according to the total amount of slag entering the water quenching tank and the amount of slag removed from the water quenching tank; the total amount of slag is positively correlated with the difference between the total amount of raw materials transported by the kiln conveyor and the amount of unreacted raw materials; the amount of slag removed is positively correlated with the amount of slag scooped underwater by the grab bucket in the water quenching tank; Calculating the ratio of the remaining slag amount to the designed accumulation amount to obtain the volume ratio inside the water quenching tank; The steelmaking strategy is adjusted according to the volume ratio to control the amount of slag in the water quenching tank.

2. The control method according to claim 1, characterized in that: Also includes: When the kiln slag is naturally piled up, the geometric body formed between the kiln slag and the lower edge of the rotary kiln through which the slag is flushed is equivalent to the first standard geometric body; The part of the first standard geometric body where the slag is not piled up is equivalent to the second standard geometric body; Calculating a first volume of the first standard geometric body and a second volume of the second standard geometric body; The difference between the first volume and the second volume is calculated to obtain a designed stacking volume.

3. The control method according to claim 1, characterized in that: Also includes: Calculate the theoretical slag formation ratio of kiln slag produced by the raw materials during the smelting process according to the exhaust gas composition of the raw materials; Obtaining the total amount of raw materials transported by the kiln conveyor and the amount of unreacted raw materials; Calculating the difference between the total amount of the raw material and the amount of the unreacted raw material; The product of the slag formation ratio and the difference is calculated to obtain the total amount of kiln slag entering the water quenching tank.

4. The control method according to claim 3, characterized in that: The method of calculating the theoretical slag formation ratio of kiln slag generated by the raw material in the smelting process according to the exhaust gas composition of the raw material includes: The theoretical slag formation ratio is calculated according to the ratio of raw materials discharged in the flue gas; the ratio of raw materials discharged in the flue gas is obtained by the amount of raw materials discharged in the flue gas, the amount of raw materials entering the rotary kiln and the mass of reactants discharged in the flue gas; Set the slag ratio correction threshold; The theoretical slag formation ratio is corrected according to the slag formation ratio correction threshold value.

5. The control method according to claim 4, characterized in that: The step of correcting the theoretical slag formation ratio according to the slag formation ratio correction threshold value comprises: If the ratio of the slag removal amount to the designed accumulation amount is greater than or equal to the slag formation ratio correction threshold, the correction coefficient is calculated according to the average value of the theoretical value of the slag formation ratio before correction and the current slag formation ratio; the product of the correction coefficient and the theoretical value of the slag formation ratio at the next moment is the slag formation ratio correction value at the next moment; If the ratio of the slag removal amount to the designed accumulation amount is less than the slag formation ratio correction threshold, the amount of slag that has been produced is calculated based on the theoretical slag formation ratio.

6. The control method according to claim 1, characterized in that: Also includes: Calculating the position of the grab bucket according to the position parameters of the grab bucket when grabbing the kiln slag; When it is detected that the grab bucket reaches a preset position after grabbing the slag, the volume of the slag currently grabbed is obtained to obtain the current amount of slag removed.

7. The control method according to claim 6, characterized in that: The preset position is located below the water surface of the water quenching pool; the distance between the top of the grab bucket and the water surface of the water quenching pool is a first preset distance, and the distance between the bottom of the grab bucket and the top of the accumulated slag is a second preset distance; the first preset distance and the second preset distance are both greater than 0.

8. The control method according to claim 1, characterized in that: When adjusting the steelmaking strategy according to the volume ratio, it includes: Set the volume ratio threshold; If the volume ratio is less than the volume ratio threshold, the input amount of raw materials is increased, and / or the grab bucket is controlled to reduce the frequency of scooping up the kiln slag; If the volume ratio is greater than or equal to the volume ratio, the input amount of raw materials is reduced, and / or the grab bucket is controlled to increase the frequency of scooping up the kiln slag.

9. The control method according to claim 1, characterized in that: Also includes: The remaining allowable time is calculated according to the designed accumulation amount of the water quenching tank, the current volume ratio, the remaining allowable capacity of the water quenching tank and the average instantaneous value of the weight of the raw materials on the kiln conveyor; the remaining allowable capacity includes the remaining allowable volume and remaining allowable mass of the kiln slag that the water quenching tank can still accommodate; the remaining allowable time is the time required for the kiln slag capacity in the current water quenching tank to reach the designed accumulation amount; If the remaining allowed time is greater than the equipment maintenance time, performing equipment maintenance on the equipment carrying the grab; If the remaining allowed time is less than the equipment maintenance time, the input amount of raw materials is reduced, or the grab bucket is controlled to increase the frequency of scooping slag to reduce the volume ratio of the water quenching tank.

10. A production control system for increasing iron and reducing zinc, applied to the steel smelting process, wherein the mechanism used in the steel smelting process includes a kiln conveyor, a rotary kiln, a grab bucket and a water quenching tank, characterized in that: include: Emulators and processors; The simulator is used to calculate the designed accumulation amount of the slag in the water quenching tank in combination with the geometric characteristics of the slag when it is accumulated in the water quenching tank; The processor is used to obtain the current amount of remaining slag in the water quenching tank according to the total amount of slag entering the water quenching tank and the amount of slag removed from the water quenching tank; the total amount of slag is positively correlated with the difference between the total amount of raw materials transported by the kiln conveyor and the amount of unreacted raw materials; the amount of slag removed is positively correlated with the amount of slag scooped underwater by the grab bucket in the water quenching tank; The processor is also used to calculate the ratio of the remaining slag amount to the designed accumulation amount to obtain the volume ratio inside the water quenching tank; The processor is also used to adjust the steel smelting strategy according to the volume ratio to control the amount of slag in the water quenching tank.

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