Method for controlling the volume of a coke pile in the hearth of a blast furnace

Abstract

The application discloses a control method for the volume of a coke pile in a blast furnace hearth, comprising the following steps: obtaining the height from the set taphole channel on the inner side of the hearth to the bottom level of the hearth; obtaining the proportion of the slag-iron volume of the set taphole in the bottom of the hearth according to the total weight of the generated molten iron and the generated slag, the actual weight of the molten iron and the actual weight of the slag discharged through the set taphole of the blast furnace, the total weight of the molten iron and the total weight of the slag not discharged in the hearth, the diameter of the hearth, the density of the molten iron, the density of the slag, the height from the set taphole channel on the inner side of the hearth to the bottom level of the hearth; obtaining the proportion of the volume of the coke pile in the bottom of the hearth; and executing the step of cleaning the coke pile if the proportion of the volume of the coke pile in the bottom of the hearth exceeds a set value. The application is helpful to adjust the activity of the hearth by calculating and controlling the volume of the coke pile in the blast furnace hearth, thereby improving various indexes of the blast furnace and reducing the production cost.

Description

Technical Field

[0001] This invention relates to the field of blast furnace technology, and in particular to a method for controlling the volume of coke pile inside the blast furnace hearth. Background Technology

[0002] The blast furnace hearth is the area in the blast furnace where slag and iron are stored. Inside the hearth, especially in the center, there is a large amount of coke pile. The size of the coke pile directly affects the adjustment of parameters such as the blast furnace hearth blast energy, thus affecting the operating efficiency of the blast furnace.

[0003] However, there is currently no scientific method to determine the size of the coke pile in the center of the hearth. We can only rely on human experience to predict the coke accumulation in the hearth, which lacks accuracy and objectivity. Summary of the Invention

[0004] This invention provides a method for controlling the volume of coke pile in the hearth of a blast furnace, so as to obtain the proportion of the coke pile volume in the center of the hearth, which plays a guiding role in the adjustment of the activity of the blast furnace hearth.

[0005] The method for controlling the volume of coke piles inside the blast furnace hearth includes:

[0006] Based on the actual depth of the set taphole, the theoretical depth of the taphole during design, and the height from the outer taphole to the bottom of the hearth, the height from the inner taphole channel to the bottom of the hearth is obtained.

[0007] Based on the total weight of molten iron and slag generated in the designated taphole area during the blast furnace production period, the actual weight of molten iron and slag discharged from the blast furnace through the designated taphole, the total weight of molten iron and slag not discharged from the hearth, the hearth diameter, molten iron density, slag density, and the height from the designated taphole channel inside the hearth to the bottom horizontal plane of the hearth, the slag-iron volume of the designated taphole is obtained as a percentage of the bottom of the hearth.

[0008] The volume percentage of coke pile at the bottom of the hearth is obtained based on the percentage of slag and iron volume at the set taphole to the bottom of the hearth.

[0009] If the volume ratio of the coke pile at the bottom of the furnace hearth exceeds a set value, then the coke pile cleaning step is performed.

[0010] The technical solution of this invention can accurately calculate and predict coke accumulation in the hearth. Specifically, by utilizing the volume relationship between molten iron and slag generated and discharged within a set time period during blast furnace production, the proportion of slag-iron volume at a set taphole to the bottom of the hearth is obtained, thus yielding the volume proportion of coke pile at the bottom of the hearth. This invention quantifies the volume content of coke pile generated in the hearth region, effectively guiding the adjustment of the internal state of the blast furnace hearth. In summary, by controlling the volume of coke pile in the blast furnace hearth, this invention helps to regulate the activity of the hearth, thereby improving various blast furnace indicators and reducing production costs.

[0011] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a flowchart of a method for controlling the volume of coke pile in the hearth of a blast furnace according to an embodiment of the present invention;

[0014] Figure 2 This is a partial structural schematic diagram of a blast furnace according to an embodiment of the present invention;

[0015] Figure 3 This is a flowchart of a method for obtaining the proportion of slag-iron volume at a set taphole to the bottom of the hearth, according to an embodiment of the present invention.

[0016] Figure 4 This is a flowchart of another method for controlling the volume of coke pile in the hearth of a blast furnace according to an embodiment of the present invention. Detailed Implementation

[0017] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0018] It should be noted that the terminology in the specification, claims, and accompanying drawings of this invention is used to distinguish similar objects and is not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0019] In this embodiment of the invention, a blast furnace is an industrial device used to smelt iron ore to produce pig iron. It is typically constructed of refractory materials and undergoes a chemical reaction at a high internal temperature to reduce the iron in the iron ore into molten iron. Molten iron refers to the liquid state of molten iron generated through a reduction reaction during the blast furnace smelting process; its main component is iron, and it usually contains a certain amount of elements such as carbon, silicon, and manganese. Slag refers to the solid waste or byproduct generated during the blast furnace smelting process, and its components include silicates, aluminates, iron oxides, and other impurities. During production, coke tends to accumulate at the bottom of the blast furnace, affecting its smelting efficiency.

[0020] Figure 1 This is a flowchart illustrating a method for controlling the volume of coke pile inside a blast furnace hearth, as provided in Embodiment 1 of the present invention. This embodiment is applicable to situations where the volume of the coke pile inside the blast furnace hearth is uncertain. This method can be executed by a device for controlling the volume of the coke pile inside the blast furnace hearth. This control device can be implemented in hardware and / or software and can be configured in a computer device. Figure 1 As shown, the method includes:

[0021] S110. Based on the actual depth of the set taphole, the theoretical depth of the taphole during design, and the height from the outer taphole to the bottom of the furnace hearth, obtain the height from the inner taphole channel to the bottom of the furnace hearth.

[0022] In this embodiment of the invention, the taphole is an opening used to discharge molten iron during the blast furnace smelting process; the blast furnace may include multiple tapholes, for example, including one, two, three or four tapholes; the taphole is one of the tapholes specified in this embodiment of the invention. Figure 2 This is a partial structural schematic diagram of a blast furnace according to an embodiment of the present invention, such as... Figure 2As shown, the blast furnace has furnace walls on both sides, with the taphole penetrating inside the furnace walls. There is a clay sack at the taphole on the inner side of the furnace walls, and coke piles accumulate in the hearth inside the blast furnace. The actual depth of the taphole refers to the actual depth the taphole penetrates into the furnace wall during drilling or machining. The theoretical depth of the taphole in the design refers to the ideal depth calculated based on process requirements and operating parameters during the blast furnace design phase; the theoretical depth of the taphole in the design is the distance from the outer side of the furnace wall to the center point of the bottom of the hearth.

[0023] Optionally, the actual depth of the iron opening can be determined based on the stroke of the drill rod when it passes through the iron opening.

[0024] In this embodiment of the invention, the taphole drill rod is a mechanical device used for drilling holes in the blast furnace taphole. It is typically equipped with a drill bit and a motor, enabling precise drilling operations under high temperature and high pressure conditions. During the drilling process through the taphole (or taphole clay), the drill rod moves downwards along a predetermined path. When the drill rod completely penetrates the taphole and touches the furnace bottom, its stroke length is equal to the actual depth of the taphole. Based on the actual depth of the taphole and the taphole inclination angle, the vertical height H3 of the taphole channel in the hearth region can be calculated. For example, the following formula is used for calculation:

[0025] H3=La×sinβ1

[0026] Where La is the actual depth of the taphole, and β1 is the taphole tilt angle.

[0027] Optionally, based on the actual depth of the set taphole, the theoretical depth of the taphole during design, and the height from the outer taphole to the bottom of the hearth, the height from the inner taphole channel to the bottom of the hearth can be obtained, including calculation using the following formula:

[0028] ΔHa=(L-La)÷L×H0

[0029] Where ΔHa is the height from the inner side of the furnace hearth to the bottom horizontal plane of the furnace hearth, L is the theoretical depth of the tap during design, La is the actual depth of the tap, and H0 is the height from the outer side of the tap to the bottom horizontal plane of the furnace hearth.

[0030] S120. Based on the total weight of molten iron and slag generated in the taphole area during the blast furnace production period, the actual weight of molten iron and slag discharged from the taphole, the total weight of molten iron and slag not discharged from the hearth, the hearth diameter, molten iron density, slag density, and the height from the taphole channel to the bottom of the hearth, the slag-iron volume of the taphole is obtained as a percentage of the bottom of the hearth.

[0031] Here, the hearth diameter refers to the inner diameter of the blast furnace hearth. The iron density refers to the ratio of the mass to the volume of molten iron generated during the blast furnace smelting process; for example, in this embodiment of the invention, the iron density is taken as 7.0 tons / m³. 3 Slag density refers to the ratio of the mass to the volume of slag generated during blast furnace smelting; for example, in this embodiment of the invention, the slag density is taken as 3.0 tons / m³. 3 Iron slag is a shorthand term for the mixture of molten iron and furnace slag. The slag-iron volume refers to the total volume of slag and molten iron generated during the blast furnace smelting process.

[0032] S130. Based on the set percentage of slag and iron volume at the taphole to the bottom of the hearth, obtain the percentage of coke pile volume at the bottom of the hearth.

[0033] In this embodiment of the invention, the volume ratio of the coke pile at the bottom of the hearth refers to the ratio of the volume occupied by the coke pile at the bottom of the blast furnace to the total usable volume.

[0034] The slag-iron volume is the sum of the volume of molten iron that has not been discharged from the blast furnace and the volume of slag that has not been discharged. The hearth contains coke piles and slag-iron, and the sum of their volumes is the volume of the entire bottom of the hearth. Therefore, the volume ratio of the coke pile at the bottom of the hearth can be obtained by setting the proportion of the slag-iron volume at the taphole to the bottom of the hearth.

[0035] S140. If the volume ratio of the coke pile at the bottom of the furnace hearth exceeds the set value, then the coke pile cleaning step is performed.

[0036] In this embodiment of the invention, the set value refers to the maximum allowable value preset for the volume ratio of coke pile at the bottom of the hearth; when the volume ratio of coke pile exceeds the set value, measures need to be taken to restore the normal operation of the blast furnace. Cleaning the coke pile is an important part of blast furnace maintenance. It can improve the airflow channel, enhance the airflow distribution in the furnace, improve fuel combustion efficiency, and thus increase the output of molten iron; at the same time, it reduces wear on the inside of the hearth and extends the service life of the blast furnace and related equipment.

[0037] When the volume percentage of coke pile at the bottom of the hearth exceeds a set value, it indicates excessive coke accumulation, which obstructs normal airflow, affects fuel combustion and chemical reactions, leads to incomplete reduction of the burden, and reduces blast furnace efficiency. It also causes abnormal internal pressure, increasing safety risks. Therefore, when the volume percentage of coke pile exceeds the set value, the coke pile should be cleaned immediately to ensure the normal operation of the blast furnace.

[0038] Optionally, hot washing of the furnace or increasing the blast energy of the furnace hearth can be used to clean the coke pile and maintain the coke pile in the furnace hearth within a set range.

[0039] In this embodiment of the invention, the hot furnace cleaning method is a technique for cleaning and maintaining the internal equipment of a blast furnace. It uses high-temperature gas or liquid to clean scale, coke, and other impurities inside the furnace, thereby maintaining the blast furnace's operating efficiency and safety. The method of increasing the blast furnace hearth blast energy refers to improving the airflow distribution and reaction conditions within the blast furnace by increasing the efficiency and flow rate of the blast.

[0040] The technical solution of this invention utilizes the volume relationship between molten iron and slag generated and discharged within a set time period during blast furnace production. This allows for the determination of the proportion of slag-iron volume at the taphole to the bottom of the hearth, thereby obtaining the volume proportion of coke pile at the bottom of the hearth. This quantifies the volume content of coke pile generated in the hearth region, effectively guiding the adjustment of the internal state of the blast furnace hearth. Furthermore, the coke pile cleaning step effectively reduces the volume of coke pile within the hearth. In summary, this invention, by controlling the volume of coke pile within the blast furnace hearth, helps regulate the hearth's activity, thereby improving various blast furnace indicators and reducing production costs.

[0041] Figure 3 This is a flowchart illustrating a method for obtaining the percentage of slag-iron volume at a designated taphole to the bottom of the hearth, according to an embodiment of the present invention. Based on the above embodiments, alternative methods may be used, such as... Figure 3 As shown, the method for obtaining the proportion of slag-iron volume at a set taphole to the bottom of the hearth includes the following steps:

[0042] S131. Based on the total weight of the generated molten iron and the actual weight of the discharged molten iron, obtain the total weight of the molten iron that was not discharged from the hearth.

[0043] In this embodiment of the invention, the total weight of molten iron generated refers to the total mass of molten iron generated through the reduction reaction during the blast furnace smelting process. The actual weight of molten iron discharged refers to the mass of molten iron actually discharged from the blast furnace taphole. The total weight of molten iron not discharged from the hearth refers to the total mass of molten iron that has been generated inside the blast furnace but has not yet been discharged.

[0044] Alternatively, the following formula can be used for calculation:

[0045] Qa1=M1-M3

[0046] Where Qa1 is the total weight of molten iron that has not been discharged, M1 is the total weight of molten iron generated, and M3 is the weight of molten iron that has actually been discharged.

[0047] S132. Based on the weight of the generated slag and the actual weight of the discharged slag, obtain the weight of the slag that was not discharged from the hearth.

[0048] In this embodiment of the invention, the generated slag weight refers to the total mass of waste or by-products generated through chemical reactions during the blast furnace smelting process. The actual discharged slag weight refers to the mass of slag actually discharged from the blast furnace slag outlet within a specific time period. The slag weight not discharged from the hearth refers to the total mass of slag that has been generated inside the blast furnace but has not yet been discharged.

[0049] Alternatively, the following formula can be used for calculation:

[0050] Qa2=M2-M4

[0051] Where Qa2 is the weight of slag not discharged, M2 is the weight of generated slag, and M4 is the weight of slag actually discharged.

[0052] S133. Based on the total weight of the molten iron that has not been discharged, the diameter of the hearth, the density of the molten iron, and the density of the slag, the height of the molten iron remaining in the hearth is obtained.

[0053] In this embodiment of the invention, the height of the residual molten iron level in the hearth refers to the height occupied by the molten iron that has not been discharged, when the blast furnace contains only the corresponding weight of the molten iron. The volume of the residual molten iron in the hearth can be obtained based on the relationship between the total weight of the molten iron and the density of the molten iron. The bottom surface of the blast furnace hearth is circular, and the interior of the blast furnace hearth can be regarded as a cylinder. Since molten iron is a liquid, the volume occupied by the molten iron in the blast furnace can also be regarded as a cylinder. Therefore, when the volume of the residual molten iron in the hearth and the diameter of the hearth are known, the height of the residual molten iron level in the hearth can be obtained using the formulas for the area of ​​a circle and the volume of a cylinder.

[0054] Alternatively, the following formula can be used for calculation:

[0055] Hq1=Qa1÷ρ1÷(π*0.5D*0.5D)

[0056] Where Hq1 is the height of the molten iron that has not been drained, Qa1 is the total weight of the molten iron that has not been drained, ρ1 is the density of the molten iron, and D is the diameter of the hearth.

[0057] S134. Based on the weight of the undischarged slag, the diameter of the hearth, the density of the molten iron, and the density of the slag, the height of the slag surface remaining in the hearth is obtained.

[0058] In this embodiment of the invention, the slag surface height of the slag remaining in the hearth refers to the height occupied by the undischarged slag when the blast furnace contains only the corresponding weight of undischarged slag. The volume of the slag remaining in the hearth can be obtained based on the relationship between the weight of the undischarged slag and the slag density. The bottom surface of the blast furnace hearth is circular, and the interior of the blast furnace hearth can be regarded as a cylinder. The slag is considered to be uniformly distributed inside the hearth, that is, the volume occupied by the slag in the blast furnace can also be regarded as a cylinder. Therefore, when the volume of the slag remaining in the hearth and the diameter of the hearth are known, the slag surface height of the slag remaining in the hearth can be obtained based on the formula for the area of ​​a circle and the formula for the volume of a cylinder.

[0059] Alternatively, the following formula can be used for calculation:

[0060] Hq2=Qa2÷ρ2÷(π*0.5D*0.5D)

[0061] Where Hq2 is the height of the slag surface before discharge, Qa2 is the weight of the slag before discharge, ρ2 is the slag density, and D is the diameter of the hearth.

[0062] S135. Based on the height of the residual molten iron level in the hearth, the height of the residual slag level in the hearth, and the height from the set tap hole to the bottom of the hearth, the proportion of the slag-iron volume at the set tap hole to the bottom of the hearth is obtained.

[0063] In this embodiment of the invention, slag refers to a mixture of molten iron and slag. The bottom surface of the blast furnace hearth is circular, and the interior of the blast furnace hearth can be considered as a cylinder. The volume occupied by the molten iron and slag inside the blast furnace can also be considered as a cylinder. The base area of ​​the cylinder is fixed. According to the formula for the volume of a cylinder: the volume of a cylinder equals the base area * the height, the proportion of the slag volume to the bottom of the hearth is the ratio of the sum of the molten iron level and the slag level to the height from the set taphole to the horizontal plane at the bottom of the hearth.

[0064] Alternatively, the following formula can be used for calculation:

[0065] K1 = (Hq1 + Hq2) ÷ ΔHa × 100%

[0066] Wherein, K1 is the percentage of the slag-iron volume at the taphole to the bottom of the hearth, Hq1 is the height of the residual molten iron level in the hearth, Hq2 is the height of the residual slag level in the hearth, and ΔHa is the height from the taphole channel inside the hearth to the horizontal plane at the bottom of the hearth.

[0067] Optionally, based on the set percentage of slag and iron volume at the taphole to the bottom of the hearth, the percentage of coke pile volume at the bottom of the hearth is obtained, including calculation using the following formula:

[0068] Ya = 1 - K1

[0069] Where Ya is the volume percentage of the coke pile at the bottom of the hearth, and K1 is the volume percentage of the slag and iron at the taphole at the bottom of the hearth.

[0070] In this embodiment of the invention, if the volume ratio of the bottom of the furnace hearth is 1, that is, the total volume ratio of the slag, iron and coke pile that has not been discharged in the furnace hearth is 1, the volume ratio of the slag and iron to the bottom of the furnace hearth is K1, and the bottom of the furnace hearth only contains slag, iron and coke pile, so the volume ratio of the coke pile is 1-K1.

[0071] Figure 4 This is a flowchart of another method for controlling the volume of coke pile in the hearth of a blast furnace according to an embodiment of the present invention. Based on the above embodiments, such as... Figure 4 As shown, before step S110, which obtains the height from the set iron tap hole to the bottom of the furnace hearth based on the actual depth of the set iron tap, the theoretical depth of the iron tap during design, and the height from the set iron tap outside to the bottom of the furnace hearth, the process further includes: S150, obtaining the height of the slag and iron liquid level generated inside the furnace hearth, and determining whether a coke pile is generated inside the furnace hearth based on the height of the slag and iron liquid level.

[0072] If there is coke pile, then execute step S110: based on the actual depth of the set taphole, the theoretical depth of the taphole during design, and the height from the outer taphole to the bottom of the hearth, obtain the height from the set taphole channel to the bottom of the hearth. If there is no coke pile, then wait for the set time length and then execute step S150 again.

[0073] Optionally, methods for obtaining the height of the molten slag and iron generated in the hearth may include:

[0074] The height of the molten iron level inside the furnace is obtained based on the total weight of the molten iron, the density of the molten iron, and the diameter of the furnace hearth.

[0075] In this embodiment of the invention, the height of the molten iron level generated in the hearth refers to the height occupied by the molten iron when the furnace contains only the corresponding weight of the generated molten iron. The volume of the molten iron generated in the hearth can be obtained based on the relationship between the total weight of the generated molten iron and the density of the molten iron. The bottom surface of the blast furnace hearth is circular, and the interior of the blast furnace hearth can be regarded as a cylinder. Since molten iron is a liquid, the volume occupied by the molten iron in the blast furnace can also be regarded as a cylinder. Therefore, when the volume of the molten iron generated in the hearth and the diameter of the hearth are known, the height of the molten iron level generated in the hearth can be obtained using the formulas for the area of ​​a circle and the volume of a cylinder.

[0076] Alternatively, the following formula can be used for calculation:

[0077] H1 = M1 ÷ ρ1 ÷ (π * 0.5D * 0.5D)

[0078] Where H1 is the height of the molten iron generated in the hearth, M1 is the total weight of the generated molten iron, ρ1 is the density of the molten iron, and D is the diameter of the hearth.

[0079] The height of the slag surface inside the hearth is obtained based on the weight of the generated slag, the slag density, and the diameter of the hearth.

[0080] In this embodiment of the invention, the slag surface height generated in the hearth refers to the height occupied by the generated slag when only the corresponding weight of the generated slag is contained inside the blast furnace. The volume of the generated slag in the hearth can be obtained based on the relationship between the weight of the generated slag and the slag density. The bottom surface of the blast furnace hearth is circular, and the interior of the blast furnace hearth can be regarded as a cylinder. The slag is considered to be uniformly distributed inside the hearth, that is, the volume occupied by the slag in the blast furnace can also be regarded as a cylinder. Therefore, when the volume of the generated slag in the hearth and the diameter of the hearth are known, the slag surface height generated in the hearth can be obtained based on the formula for the area of ​​a circle and the formula for the volume of a cylinder.

[0081] Alternatively, the following formula can be used for calculation:

[0082] H2 = M2 ÷ ρ2 ÷ (π * 0.5D * 0.5D)

[0083] Where H2 is the height of the slag surface generated in the hearth, M2 is the weight of the generated slag, ρ2 is the slag density, and D is the diameter of the hearth.

[0084] The height of the molten iron and slag in the hearth is obtained by measuring the height of the molten iron and the height of the slag in the hearth; where slag and slag are a mixture of molten iron and slag.

[0085] In this embodiment of the invention, slag iron refers to a mixture of molten iron and slag. Therefore, the liquid level of slag iron generated in the hearth is the sum of the liquid level of molten iron and the slag level in the hearth.

[0086] Alternatively, the following formula can be used for calculation:

[0087] H = H1 + H2

[0088] Where H is the height of the molten iron and slag generated in the hearth, H1 is the height of the molten iron generated in the hearth, and H2 is the height of the slag generated in the hearth.

[0089] The technical solution of this invention obtains the slag-iron molten metal level in the hearth by measuring the total weight of the generated molten iron, the weight of the generated slag, the slag density, and the hearth diameter. This facilitates subsequent judgment of the taphole's working status and allows for timely adjustments to the blast furnace status based on changes in the slag-iron molten metal level, thereby optimizing the overall operation of the blast furnace.

[0090] Optionally, after obtaining the slag-iron molten iron level in the hearth based on the height of the molten iron level and the height of the slag level, the method further includes:

[0091] Based on the height of the molten iron level generated in the hearth, the height of the molten slag and iron level generated in the hearth, and the height from the taphole channel set on the inside of the hearth to the horizontal plane at the bottom of the hearth, it can be determined whether coke piles are generated inside the hearth.

[0092] In this embodiment of the invention, the product discharged from the taphole can be detected by a detection device. Based on the type of product discharged from the taphole, combined with the height of the molten iron level generated in the hearth, the height of the slag and iron level generated in the hearth, and the height from the taphole channel set on the inside of the hearth to the bottom of the hearth, it can be determined whether there is coke pile inside the hearth.

[0093] If the height of the taphole channel inside the hearth from the bottom of the hearth is lower than the height of the molten iron generated inside the hearth, then the taphole channel inside the hearth is below the molten iron surface, and it is impossible to determine whether there is coke pile.

[0094] If the height of the taphole channel inside the hearth from the bottom of the hearth is higher than the height of the molten iron generated inside the hearth but lower than the height of the molten slag and iron generated inside the hearth, and the liquid discharged from the taphole contains molten iron, then there will be coke piles inside the hearth.

[0095] If the height of the taphole channel inside the hearth from the bottom of the hearth is higher than the height of the molten slag and iron generated inside the hearth, and the liquid discharged from the taphole contains at least one of molten iron or slag, then there is a coke pile inside the hearth.

[0096] The technical solution of this invention determines whether coke piles are generated inside the furnace hearth by combining the type of product discharged from the taphole with the height of the molten iron level generated inside the furnace hearth, the height of the slag and iron level generated inside the furnace hearth, and the height of the taphole channel inside the furnace hearth to the bottom horizontal plane. This provides guidance for subsequent operations and ensures the safe and efficient operation of the blast furnace.

[0097] Based on the above embodiments, in order to better understand the technical solutions provided by the embodiments of the present invention, the embodiments of the present invention also provide a specific implementation process using specific numerical values. For example, the method for controlling the volume of coke pile in the blast furnace hearth is implemented in the following manner:

[0098] Based on the iron ore grade and fuel composition of the blast furnace feed, the weight of slag and iron generated in real time during the blast furnace smelting process can be obtained, with a slag ratio of 300 kg / t. The blast furnace hearth diameter D = 10 meters, and the bottom horizontal plane inside the hearth is fixed at zero.

[0099] During blast furnace production, within a set time period, the rate of blast furnace smelting and producing molten iron is S = 5t / min, the total slag and iron discharge time t is 100 minutes, and the total weight of molten iron generated in the hearth is M1: M1 = S * t = 100 * 5 = 500 tons. The weight of the generated slag is proportional to the total weight of the generated molten iron, and is taken as 0.300 times, that is, the weight of the generated slag is M2: M2 = 500 × 0.300 = 150 tons.

[0100] Based on the total weight of the molten iron, its density, and the diameter of the hearth, the height H1 of the molten iron level inside the hearth is obtained, where the density ρ1 of the molten iron is taken as 7 tons / m³. 3 The furnace hearth diameter D is 10 meters: H1 = M1 ÷ ρ1 ÷ (π * 0.5D * 0.5D) = 500 ÷ 7 ÷ (3.14 * 0.5 * 10 * 0.5 * 10) = 0.91 meters; Based on the weight of the generated slag, the slag density, and the furnace hearth diameter, the slag surface height H2 generated inside the furnace hearth is obtained, where the slag density ρ2 is taken as 3.0 tons / m³. 3 The hearth diameter D is taken as 10 meters: H2 = M2 ÷ ρ2 ÷ (π * 0.5D * 0.5D) = 150 ÷ ​​3.0 ÷ (3.14 * 0.5 * 10 * 0.5 * 10) = 0.64 meters; the height H of the molten iron and slag surface generated in the hearth is the sum of the height H1 of the molten iron surface and the height H2 of the slag surface: H = H1 + H2 = 0.91 + 0.64 = 1.55 meters. This height is a theoretical height; due to the coke pile in the center of the hearth, the actual height of the molten iron surface in the hearth will definitely be greater than 1.55 meters.

[0101] Designate taphole A as the taphole location, and calculate the percentage of slag and iron volume at taphole A relative to the bottom of the hearth:

[0102] Determine the values ​​of the known variables: During the taphole opening process, based on the stroke of the taphole drill rod when it passes through the taphole, the actual depth La of taphole A is obtained: La = 3.0 meters; the theoretical depth L of taphole A during design is 3.3 meters; the height H0 from the outer taphole of taphole A to the horizontal plane at the bottom of the hearth is 3.5 meters; the diameter of the taphole channel Da = 50 mm = 0.05 meters; the taphole inclination angle β1 is 10°.

[0103] Based on the above variable values, the vertical height H3 of the taphole channel in the hearth area can be obtained: H3 = La × sinβ1 = 3.0 × 0.1736 = 0.5208 meters. Since taphole A is on the outside, the starting point on the furnace wall is fixed. The height ΔHa from the taphole channel inside the hearth to the bottom horizontal plane of the hearth can be obtained as: ΔHa = (L - La) ÷ L × H0 = (3.3 - 3.0) ÷ 3.3 × 3.5 ≈ 0.318 meters. Therefore, ΔHa < H1, indicating that the taphole channel inside the hearth is below the molten iron surface, and it is impossible to determine whether there is coke buildup.

[0104] After tap A is opened, at time t1 (0:00), slag and iron begin to be discharged from the hearth. As the discharge time increases, the weight of the slag and iron discharged from tap A is measured dynamically in real time. At time t3 (1:40), air is supplied to the blast furnace tap, indicating that the slag and iron molten level in the hearth is lower than the height from the tap A channel inside the hearth to the bottom of the hearth, thus sealing the tap. During the 100 minutes from t1 to t3, the actual weight of molten iron discharged from the blast furnace is M3 = 480 tons, and the actual weight of slag discharged is M4 = 132 tons. The actual height of the discharged molten iron liquid level H4 is: H4 = M3 ÷ ρ1 ÷ (π * 0.5D * 0.5D) = 480 ÷ 7 ÷ (3.14 * 0.5 * 10 * 0.5 * 10) = 0.87 meters; the actual height of the discharged slag liquid level H5 is: H5 = M4 ÷ ρ2 ÷ (π * 0.5D * 0.5D) = 132 ÷ 3.0 ÷ (π * 0.5 * 10 * 0.5 * 10) = 0.56 meters; the actual total height of the discharged slag and iron liquid level is H4 + H5 = 0.87 + 0.56 = 1.43 meters.

[0105] When air comes in through the taphole, the slag and iron below the height of the bottom of the hearth cannot be discharged. The total weight of the molten iron that is not discharged in the hearth is Qa1: Qa1=M1-M3=500-480=20 tons. The height of the molten iron remaining in the hearth, Hq1, is Hq1=Qa1÷ρ1÷(π*0.5D*0.5D)=20÷7.0÷(3.14*0.5*10*0.5*10)=0.036 meters. The weight of the slag that has not been discharged from the hearth is Qa2: Qa2 = M2 - M4 = 18 tons. The height of the slag surface remaining in the hearth is Hq2: Hq2 = Qa2 ÷ ρ2 ÷ (π * 0.5D * 0.5D) = 18 ÷ 3.0 ÷ (3.14 * 0.5 * 10 * 0.5 * 10) = 0.076 meters. The slag and iron remaining at the bottom of the hearth occupy the total height of the hearth by Hq1 + Hq2 = 0.036 + 0.076 = 0.112 meters.

[0106] The above steps yielded a height ΔHa from the A-tap channel inside the hearth to the horizontal plane at the bottom of the hearth, which is 0.318 meters. Therefore, the percentage K1 of the slag and iron volume at the A-tap to the bottom of the hearth is: K1 = (Hq1 + Hq2) ÷ ΔHa × 100% = (0.036 + 0.076) ÷ 0.318 × 100% = 35%. Thus, the percentage Ya of the coke pile at the bottom of the hearth is: Ya = 1 - K1 = 1 - 35% = 65%. Conclusion: After the slag and iron are discharged from the A-tap, the percentage of the coke pile at the bottom of the hearth is 65%. The decision to perform the coke pile cleaning step is based on the set coke pile volume threshold.

[0107] As slag and iron are discharged from multiple tapholes in the blast furnace, the volume ratio of coke pile at the bottom of the hearth increases, and the results more accurately reflect the coke pile situation in the hearth during blast furnace production. As the coke pile at the bottom of the hearth continues to increase, it becomes more difficult to make the actual taphole depth of the blast furnace deeper, and the blast furnace needs to perform coke pile cleaning operations.

[0108] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0109] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for controlling the volume of coke pile in the hearth of a blast furnace, characterized in that, include: Based on the actual depth of the set taphole, the theoretical depth of the taphole during design, and the height from the outer taphole to the bottom of the hearth, the height from the inner taphole channel to the bottom of the hearth is obtained. Based on the total weight of molten iron and slag generated in the designated taphole area during blast furnace production, the actual weight of molten iron and slag discharged from the designated taphole, the total weight of molten iron and slag not discharged from the hearth, the hearth diameter, molten iron density, slag density, and the height from the designated taphole channel to the bottom of the hearth, the slag-iron volume at the designated taphole is calculated as a percentage of the hearth bottom. Specifically, the total weight of molten iron not discharged from the hearth is calculated based on the total weight of molten iron generated and the actual weight of molten iron discharged; the total weight of slag not discharged from the hearth is calculated based on the generated slag. The weight of the slag not discharged from the hearth is obtained from the weight of the molten iron and the actual weight of the discharged slag. The height of the residual molten iron level in the hearth is obtained based on the total weight of the undischarged molten iron, the diameter of the hearth, the density of the molten iron, and the density of the slag. The height of the residual slag level in the hearth is obtained based on the weight of the undischarged slag, the diameter of the hearth, the density of the molten iron, and the density of the slag. The percentage of the slag-iron volume at the designated taphole to the bottom of the hearth is obtained based on the height of the residual molten iron level, the height of the residual slag level, and the height from the taphole opening to the bottom of the hearth. The volume percentage of coke pile at the bottom of the hearth is obtained based on the percentage of slag and iron volume at the set taphole to the bottom of the hearth. If the volume ratio of the coke pile at the bottom of the furnace hearth exceeds a set value, then the coke pile cleaning step is performed; The step of obtaining the height from the inner side of the furnace hearth to the inner bottom of the furnace hearth based on the actual depth of the set taphole, the theoretical depth of the taphole during design, and the height from the outer taphole to the bottom horizontal plane of the furnace hearth includes: calculating using the following formula: ΔHa=(L-La)÷L×H0 Wherein, ΔHa is the height from the inner side of the furnace hearth to the bottom horizontal plane of the furnace hearth, L is the theoretical depth of the tap during the design, La is the actual depth of the tap, and H0 is the height from the outer side of the tap to the bottom horizontal plane of the furnace hearth. The method further includes, before obtaining the height from the inner side of the furnace hearth to the inner bottom of the furnace hearth based on the actual depth of the set taphole, the theoretical depth of the taphole during design, and the height from the outer taphole to the bottom of the furnace hearth, the following steps: The height of the molten iron level inside the furnace is obtained based on the total weight of the generated molten iron, the density of the molten iron, and the diameter of the furnace hearth. The height of the slag surface generated inside the furnace hearth is obtained based on the weight of the generated slag, the slag density, and the diameter of the furnace hearth. The slag-iron level generated in the hearth is obtained based on the height of the molten iron and the height of the slag generated in the hearth; wherein the slag-iron is a mixture of the molten iron and the slag.

2. The method for controlling the volume of coke pile in the blast furnace hearth according to claim 1, characterized in that, The method for obtaining the actual depth of the set iron tap includes: The actual depth of the set iron opening is obtained based on the stroke of the drill rod when the opening machine drills through the iron opening.

3. The method for controlling the volume of coke pile in the blast furnace hearth according to claim 1, characterized in that, The height of the molten iron level inside the furnace is obtained based on the total weight of the generated molten iron, the density of the molten iron, and the diameter of the furnace hearth, using the following formula: H1 = M1 ÷ ρ1 ÷ (π * 0.5D * 0.5D) Wherein, H1 is the height of the molten iron generated in the hearth, M1 is the total weight of the generated molten iron, ρ1 is the density of the molten iron, and D is the diameter of the hearth. And / or, the height of the slag surface generated inside the furnace hearth is obtained based on the weight of the generated slag, the slag density, and the diameter of the furnace hearth, using the following formula: H2 = M2 ÷ ρ2 ÷ (π * 0.5D * 0.5D) Wherein, H2 is the height of the slag surface generated in the hearth, M2 is the weight of the generated slag, ρ2 is the density of the slag, and D is the diameter of the hearth. And / or, the height of the molten iron and slag generated in the hearth is obtained based on the height of the molten iron surface and the height of the slag surface, using the following formula: H = H1 + H2 Wherein, H is the height of the molten iron slag generated in the hearth, H1 is the height of the molten iron generated in the hearth, and H2 is the height of the slag surface generated in the hearth.

4. The method for controlling the volume of coke pile in the blast furnace hearth according to claim 1, characterized in that, After obtaining the slag-iron molten iron level in the hearth based on the molten iron level and the slag level in the hearth, the method further includes: Based on the height of the molten iron level generated in the hearth, the height of the molten slag and iron level generated in the hearth, and the height from the taphole channel set on the inner side of the hearth to the horizontal plane at the bottom of the hearth, it is determined whether coke piles are generated inside the hearth.

5. The method for controlling the volume of coke pile in the blast furnace hearth according to claim 1, characterized in that... The total weight of molten iron remaining in the hearth is calculated based on the total weight of the generated molten iron and the actual weight of the discharged molten iron, using the following formula: Qa1=M1-M3 Where Qa1 is the total weight of the molten iron that has not been discharged, M1 is the total weight of the generated molten iron, and M3 is the weight of the molten iron that has actually been discharged. And / or, the weight of the undischarged slag in the hearth is obtained based on the weight of the generated slag and the weight of the actually discharged slag, using the following formula: Qa2=M2-M4 Where Qa2 is the weight of the undischarged slag, M2 is the weight of the generated slag, and M4 is the weight of the actually discharged slag. And / or, the height of the residual molten iron level in the hearth is obtained based on the total weight of the undischarged molten iron, the diameter of the hearth, and the density of the molten iron, using the following formula: Hq1=Qa1÷ρ1÷(π*0.5D*0.5D) Wherein, Hq1 is the height of the molten iron that has not been drained, Qa1 is the total weight of the molten iron that has not been drained, ρ1 is the density of the molten iron, and D is the diameter of the hearth. And / or, the height of the residual slag surface inside the furnace hearth is obtained based on the weight of the undischarged slag, the diameter of the furnace hearth, and the density of the slag, calculated using the following formula: Hq2=Qa2÷ρ2÷(π*0.5D*0.5D) Wherein, Hq2 is the height of the slag surface that has not been discharged, Qa2 is the weight of the slag that has not been discharged, ρ2 is the density of the slag, and D is the diameter of the hearth. And / or, the percentage of slag-iron volume at the designated taphole relative to the bottom of the hearth is calculated based on the height of the residual molten iron level in the hearth, the height of the residual slag level in the hearth, and the height from the taphole opening on the inner side of the hearth to the horizontal plane at the bottom of the hearth, using the following formula: K1 = (Hq1 + Hq2) ÷ ΔHa × 100% Wherein, K1 is the proportion of the slag and iron volume of the set taphole to the bottom of the hearth, Hq1 is the height of the residual molten iron level in the hearth, Hq2 is the height of the residual slag level in the hearth, and ΔHa is the height from the set taphole channel inside the hearth to the horizontal plane at the bottom of the hearth.

6. The method for controlling the volume of coke pile in the blast furnace hearth according to claim 1, characterized in that, The step of obtaining the volume ratio of the coke pile at the bottom of the hearth based on the ratio of the slag and iron volume at the set taphole to the bottom of the hearth includes: calculating using the following formula: Ya = 1 - K1 Where Ya is the volume percentage of the coke pile at the bottom of the hearth, and K1 is the volume percentage of the slag and iron at the set taphole at the bottom of the hearth.

7. The method for controlling the volume of coke pile in the blast furnace hearth according to claim 1, characterized in that, If the volume ratio of the coke pile at the bottom of the furnace hearth exceeds a set value, the step of cleaning the coke pile is performed, including: The coke pile is cleaned by using hot furnace washing or increasing the kinetic energy of the furnace hearth blower, and the coke pile in the furnace hearth is kept within a set range.

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