Blast furnace operation method

Abstract

To provide an operation method for a blast furnace that makes high accuracy furnace condition control possible by determining fine powdery coal blowing conditions (for example, an amount of component of the fine powdery coal, an amount of blowing, etc.) appropriately and rapidly.SOLUTION: An aspect of the present invention provides an operation method for a blast furnace including measuring an amount of at least either one of a component of fine powdery coal blown from a blast furnace tuyere or a component of coal that is a raw material of the fine powdery coal at a position between an outlet of a coal bunker storing the coal and an inlet of a distributor that distributes and supplies the fine powdery coal to the blast furnace tuyere. In this aspect, the measurement is conducted by the neutron component analysis or the laser induction breakdown spectroscopy (LIBS).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for operating a blast furnace. [Background technology]

[0002] Conventionally, in blast furnace operation, technologies that have been considered for adjusting the injection conditions of pulverized coal (e.g., the chemical composition of the pulverized coal (specifically, the amount of constituent components) and the injection amount, etc.) taking into account the effect on the furnace conditions of the characteristics of the pulverized coal injected from the blast furnace tuyeres include technologies for controlling the amount of pulverized coal injected based on the amount of constituent components, moisture content, and particle size of the pulverized coal, technologies for adjusting the moisture content of the pulverized coal by adjusting the temperature of the conveying gas, technologies for adjusting the preheating temperature according to the volatile content of the coal, technologies for adjusting the mixing ratio of auxiliary fuel types including pulverized coal according to the blast furnace operation conditions, technologies for adjusting the amount of combustible volatile components in the pulverized coal according to the amount of oxygen in the hot blast, and technologies for changing the amount of SiO2 in the pulverized coal according to the amount of Si in the molten iron.

[0003] For example, Patent Document 1 describes a method for operating a blast furnace in which pulverized coal is injected together with hot air from a blast tuyeres, in which when multiple pulverized coals of different coal types are injected into the blast furnace or when the amount of coke per ton of pig iron (i.e., the coke ratio) is changed, the amount of heat utilized in the blast furnace is calculated in advance from the components of the pulverized coal, and the amount of pulverized coal injected or the amount of oxygen enrichment is changed so that the amount of heat generated in the blast furnace is equal before and after the change in coal type or coke ratio, thereby suppressing furnace heat fluctuations and suppressing an increase in the amount of Si in the molten pig metal.

[0004] Furthermore, as an operating method when using pulverized coal containing multiple coal types, Patent Document 2 describes a method in which the heat amount utilized in the blast furnace is calculated from the components of the pulverized coal, and the amount of pulverized coal injected is changed so that the heat amounts in the blast furnace are equal before and after changing the coal type or coke ratio, while at the same time adjusting the amount of oxygen enrichment taking into account the reaction efficiency of the gas in the furnace. Patent Document 3 describes a method in which the heat value of each type of coal is calculated in advance, and when changing the coal type, the coal types before and after the change are blended, and pulverized coal is injected while gradually changing the coal type in accordance with the difference in heat value. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 11-117009 [Patent Document 2] Japanese Patent Application Publication No. 11-61212 [Patent Document 3] Japanese Patent Application Publication No. 6-264122 Summary of the Invention [Problem to be solved by the invention]

[0006] The techniques described in the above Patent Documents 1 to 3 use analysis values ​​of coal, which is the raw material of pulverized coal, at the time of arrival to determine the pulverized coal injection conditions, so that the target pulverized coal component values ​​set based on the analysis values ​​may deviate from the component values ​​of the pulverized coal actually injected. Coal sampling is generally performed in accordance with the method described in JIS M 8811, in which 20 or 30 samples of 200 to 600 kg are taken from tens of thousands of tons of incoming coal, and then further divided (i.e., small amounts of measurement objects are taken from each sample) for component analysis, so the analysis values ​​do not necessarily fully represent the entire coal used. In addition, the amounts of components of pulverized coal are usually estimated based on the analysis values ​​of components of coal at the time of arrival and the set amount of coal cut out from the coal bin. However, such estimated values ​​cannot be said to fully accurately reflect the amounts of components of pulverized coal actually injected into the blast furnace. The pulverized coal injected into a blast furnace is often formed by blending multiple types of coal. If the estimated amounts of the constituent components of the pulverized coal deviate from the amounts of the constituent components of the pulverized coal actually injected into the blast furnace, the adjustment of the coal blend ratio may not reflect the actual situation, causing the heat balance in the furnace to be disrupted, or the simulation of the heat balance in the furnace using a blast furnace mathematical model that uses the property values ​​of the pulverized coal as input values ​​may not be performed properly.

[0007] As described above, conventional operating methods that rely on the component analysis values ​​of coal when it arrives do not allow for sufficiently accurate determination of the component amounts of the pulverized coal actually injected into the blast furnace, so there was a demand for pulverized coal injection technology that would enable more precise control of furnace conditions.

[0008] One aspect of the present invention aims to solve the above problems and provide a method for operating a blast furnace that enables high-precision control of furnace conditions by appropriately and quickly determining pulverized coal injection conditions (e.g., the amounts of constituent components of the pulverized coal, the injection amount, etc.). [Means for solving the problem]

[0009] The present invention includes the following aspects. [1] A method for operating a blast furnace, comprising measuring the amount of at least one of the components of pulverized coal injected from a blast furnace tuyere and the components of the coal that is a raw material for the pulverized coal, at a position between the outlet of a coal bin that stores the coal and the inlet of a distributor that distributes and supplies the pulverized coal to the blast furnace tuyere. [2] The method for operating a blast furnace according to the above-mentioned [1], wherein the components to be measured are one or more selected from the group consisting of C (carbon), H (hydrogen), O (oxygen), N (nitrogen), S (sulfur), ash, volatile matter and moisture. [3] A method for operating a blast furnace according to [1] or [2] above, wherein the measurements are carried out at time intervals of 240 minutes or less. [4] The method for operating a blast furnace according to any one of [1] to [3] above, wherein the measurement is carried out by neutron beam component analysis or laser-induced breakdown spectroscopy (LIBS). [5] The method for operating a blast furnace according to any one of [1] to [4] above, further comprising adjusting a blend ratio of multiple types of coal based on the results of the measurement so that the pulverized coal injected from the blast furnace tuyere has a predetermined amount of constituent components. [6] A method for operating a blast furnace according to any one of [1] to [5] above, comprising performing a blast furnace operation simulation using the results obtained by the measurement as input values ​​for a blast furnace mathematical model. [7] A method for operating a blast furnace as described in [6] above, comprising calculating an average value of the results obtained by the measurement for each predetermined time period, and using the average value as the input value. Effect of the Invention

[0010] According to one aspect of the present invention, the amount of constituent components of pulverized coal or the coal that is the raw material thereof injected into a blast furnace can be grasped without delay and accurately, thereby enabling highly accurate furnace condition control. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram illustrating an example of a configuration of a blast furnace pulverized coal injection facility. [Diagram 2] FIG. 2 is a graph showing the change over time in the C (carbon) content in coal in Example 1. [Diagram 3] FIG. 3 is a graph showing the change over time in RAR (reducing agent ratio) calculated from the C (carbon) content shown in FIG. 2. [Figure 4] FIG. 2 is a graph showing the change over time in the C (carbon) content in coal in Comparative Example 1. [Diagram 5] FIG. 5 is a graph showing the change over time in RAR (reducing agent ratio) calculated from the C (carbon) content shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, exemplary aspects of the present invention (sometimes referred to as the present embodiment in this disclosure) will be described, but the present invention is not limited to the following aspects.

[0013] One aspect of the present invention provides a method for operating a blast furnace, which includes measuring the amount of at least one of the components of pulverized coal injected from a blast furnace tuyere and the components of the coal that is the raw material for the pulverized coal (hereinafter, these are collectively referred to as "constituents in pulverized coal / coal") at a position between the outlet of a coal bin that stores the coal and the inlet of a distributor that distributes and supplies the pulverized coal to the blast furnace tuyere.

[0014] The components in pulverized coal / coal include C (carbon), H (hydrogen), O (oxygen), N (nitrogen), S (sulfur), Ash (ash content), VM (volatile matter) and moisture. T-Fe, SiO2, Al2O3, MgO, CaO, Na and K contained in the ash content may be further measured. The measurement target in the method of this embodiment is at least one of the components in pulverized coal / coal, and in one aspect, the component to be measured is C (carbon). C is a major element in pulverized coal and coal, and has a large effect on the furnace condition of a blast furnace in terms of heat value, so it is suitable as a component to be measured. Therefore, in one aspect, C (carbon) in pulverized coal or coal is selected as the component to be measured in pulverized coal / coal, and the C (carbon) content of the pulverized coal or coal is used as an index of the amount of the component in the pulverized coal or coal. The components in the pulverized coal / coal can be measured by a conventionally known measuring method, for example, the proximate analysis method is specified in JIS M 8812.

[0015] The method of the present embodiment may have the following unique advantages over conventional blast furnace operation methods. Conventionally, the amount of constituents of pulverized coal injected into a blast furnace from a blast furnace pulverized coal injection facility was only estimated based on the component analysis value at the time of coal arrival and the set amount of coal cut from the coal bin. Such an estimated value cannot be said to reflect the amount of constituents of pulverized coal actually injected into a blast furnace with sufficient accuracy, and the component analysis only at the time of coal arrival has a low measurement frequency (for example, once every few days), so that even if the type of pulverized coal and / or the injection amount are changed based on such an estimated value, it is difficult to appropriately and quickly control the furnace condition. On the other hand, in the method of the present embodiment, the amount of pulverized coal / constituents in coal is actually measured at a portion of the blast furnace pulverized coal injection facility relatively close to the blast furnace, and further, the actual measurement can be performed at any interval, and therefore at a short interval as desired (for example, once within 240 minutes). According to the above-mentioned actual measurement, the measurement time interval can be set arbitrarily without being bound by the timing of coal arrival, and in addition, the type and / or injection amount of pulverized coal can be adjusted based on the actual measurement value rather than the estimated value. In addition, based on the actual measurement value, the set coke ratio of the charge, and the blast conditions such as the blast volume, blast oxygen, blast moisture, and blast temperature can also be adjusted. Therefore, according to the method of the present embodiment, the properties of the pulverized coal actually injected into the blast furnace can be grasped without delay and accurately, so that even when the total calorific value is expected to change due to the fluctuation in the amounts of the constituent components of the pulverized coal injected into the blast furnace, the blast furnace can be operated stably by appropriately and quickly executing the operation action to control it to a constant value. Stable operation of the blast furnace contributes to the reduction of the RAR (reducing agent ratio).

[0016] The inventors of the present invention measured the C (carbon) content of coal on the conveyor after it was cut out from the coal bin in the blast furnace pulverized coal injection equipment using a neutron beam component analyzer during the conventional process from coal arrival to blast furnace injection (see Comparative Example 1 in the [Example] section below), and discovered that the C content value of the coal flowing on the conveyor and the RAR value calculated based on it fluctuated greatly over time. The inventors of the present invention also discovered that, depending on the type of coal, the above-mentioned fluctuation over time may have a certain period (for example, a period of about 1 to 4 hours). When the C content of coal, which is the raw material of the pulverized coal injected into the blast furnace, fluctuates over time, the RAR (reducing agent ratio) of the blast furnace fluctuates over time in conjunction with this, and operational action (for example, change in coal blend ratio, pulverized coal injection amount, etc.) is required to return the RAR to the target value. According to the study by the present inventors, depending on the type of coal, the range of the time-dependent variation in the RAR due to the time-dependent variation in the C content in the coal can be as much as several kg / t, so reducing the time-dependent variation in the C content in the pulverized coal is important for reducing the RAR through stable operation of the blast furnace. In the method of this embodiment, being able to set the measurement interval for the amount of pulverized coal / constituent components in the coal to a short time is advantageous in that the above-mentioned time-dependent variation in the C content in the coal can be accurately grasped and operational actions to deal with it can be appropriately and quickly taken.

[0017] In the method of this embodiment, the amount of pulverized coal / coal constituents is measured at a position between the outlet of the coal bin and the inlet of the distributor in the blast furnace pulverized coal injection equipment. FIG. 1 is a diagram for explaining an example of the configuration of a blast furnace pulverized coal injection equipment. Referring to FIG. 1, in the blast furnace pulverized coal injection equipment 10, after arrival, coal, which is a raw material of pulverized coal, is temporarily stored in a raw coal yard for each coal type, and then a required amount is cut out and stored in a coal bin. For example, when there are two types of coal, the first coal type may be stored in the raw coal yard 101a and then in the coal bin 102a, and the second coal type may be stored in the raw coal yard 101b and then in the coal bin 102b. Thereafter, the coal is cut out at an appropriate timing and transported by the transport conveyors 1a and 1b, appropriately blended, and then transported by the transport conveyor 1c, and pulverized by the pulverizer 103 to become pulverized coal. The pulverized coal is dried while being pneumatically transported by high-temperature gas, passes through a bag filter (not shown), and is temporarily stored in a hopper 104. It is then transferred to a transfer tank 105, pneumatically transported again by compressed air, passes through a bag filter (not shown), and is stored in a hopper 106. It is then transported by high-pressure nitrogen gas via an adjustment tank 107, a supply tank 108, etc., passes through a distributor 109 that distributes the gas to each tuyere of the blast furnace, and is injected into the blast furnace from a blast furnace tuyere 110.

[0018] Since tens to hundreds of tons of coal are usually stored in the coal bins 102a and 102b for a long time, if the amount of constituents in the coal is measured at a position upstream of the outlet of the coal bins 102a and 102b (i.e., the raw coal yards 101a and 101b side), there is a long time lag until the coal subjected to the measurement becomes pulverized coal and is actually injected into the blast furnace, and the measurement result is not reflected promptly and appropriately in the operation action. On the other hand, in the method of the present embodiment, the amount of pulverized coal / constituents in the coal is measured between the outlet of the coal bins 102a and 102b and the inlet of the distributor 109, so the time lag is short and the measurement result can be reflected promptly and appropriately in the thermal action, which is advantageous.

[0019] The measurement position for the amount of pulverized coal / constituents in coal is preferably close to the blast furnace in order to reduce the time lag between measurement and injection into the blast furnace. The measurement position can be determined according to the purpose, and may be, for example, (1) on the conveyor leading from the coal bin outlet to the pulverizer, and / or (2) a position between the pulverized coal and the pulverizer, where the pulverized coal is air-transported from the pulverizer to the distributor. At the position (1), the amount of constituents in the coal is measured, and at the position (2), the amount of constituents in the pulverized coal is measured. Note that, since multiple tanks are usually arranged between the position (1) and the blast furnace tuyere, and the pulverized coal is temporarily stored in each tank, measurement at the position (2) may be more advantageous.

[0020] Among the above positions (1) and (2), a more suitable measurement position is selected depending on the object to be measured. For example, regarding the above position (1), a single type of coal can be measured on the transport conveyors 1a and 1b in FIG. 1, and a mixture of coals can be measured on the transport conveyor 1c in FIG. 1. In addition, examples of the above position (2) include a position between the pulverizer 103 and the hopper 104, and a position between the transfer tank 105 and the hopper 106. From the viewpoint of proximity between the measurement position and the blast furnace, the vicinity of the inlet of the distributor 109 is particularly preferable, but since multiple supply tanks 108 are usually provided in preparation for equipment trouble, multiple devices are required when measuring at a position between the supply tank 108 and the distributor 109.

[0021] The measurement method is not particularly limited, but suitable examples include neutron beam component analysis and laser-induced breakdown spectroscopy (LIBS). Since neutron beams have excellent material permeability, neutron beam component analysis may be suitable for measurement at the position (1) above where the size of the measurement target may be large. On the other hand, laser-induced breakdown spectroscopy has excellent measurement accuracy and is particularly useful when precise measurement is required. For example, when the measurement results at the position (2) above are applied to a blast furnace mathematical model, the use of laser-induced breakdown spectroscopy may be suitable. In the blast furnace pulverized coal injection equipment 10, one or more measuring devices may be used. In addition, when the transport path of pulverized coal or coal branches into multiple paths, the arrangement of the measuring devices may be designed in various ways according to the purpose, such as installing a measuring device at a position just before the branch to save on the number of devices installed.

[0022] The measurement device may be arranged to directly measure the pulverized coal or coal on the conveying line (i.e., in-line measurement), or may be arranged to measure a collected sample, such as a sample of pulverized coal or coal led to a bypass line branched off from the conveying line. Direct measurement of the pulverized coal or coal on the conveying line is preferred in terms of the representativeness of the measurement results and the simplicity of the process.

[0023] The measurement of the pulverized coal / coal constituents may be performed at a preset time interval. In one embodiment, the measurement time interval may be preferably 240 minutes or less, or 180 minutes or less, or 150 minutes or less, or 120 minutes or less, or 90 minutes or less, or 60 minutes or less, or 30 minutes or less, or 10 minutes or less, or 5 minutes or less from the viewpoint of precise blast furnace control. The shorter the measurement time interval, the more desirable it is, but from the viewpoint of reducing the labor and cost involved in the measurement, it may be, for example, 1 minute or more. Note that, for example, the above-mentioned (1) measurement on the conveyor continuing from the coal bin outlet to the pulverizer may be performed at a time interval according to the timing of the coal being cut out from the coal bin (usually a batch process), and in one embodiment, the measurement time interval may be 1 minute or more, 5 minutes or more, 10 minutes or more, 30 minutes or more, or 60 minutes or more.

[0024] The measurement results of the amount of pulverized coal / constituents in coal can be used, for example, for calculation of blending ratios for blending multiple types of coal, various calculations for use in blast furnace mathematical models, etc. In one embodiment, the average value of the measurement results for each preset time period may be calculated, and then the average value may be used in the above calculations. For example, the measurement format may be appropriately set, such as calculating the average value for each 60 minutes from the results obtained from measurements at preset time intervals of 60 minutes or less (for example, 1 minute intervals, 5 minute intervals, 10 minute intervals, etc.).

[0025] (Application to coal blend ratio calculation) In one embodiment, the blend ratio of multiple types of coal is adjusted so that the pulverized coal injected from the blast furnace tuyeres has a preset amount of the constituent components based on the measurement results of the amount of pulverized coal / constituent components in the coal. The measurement results may be used for calculating the blend ratio directly or as an average value for each preset time period as described above. The blend ratio can be adjusted by increasing or decreasing the amount of coal cut from each coal bin.

[0026] When the measurement results of the amount of pulverized coal / coal constituents are used to adjust the coal blend ratio, it is preferable that the measurement be performed close to the coal bin. From this viewpoint, it is preferable to perform the measurement at the above-mentioned (1) position on the transport conveyor leading from the coal bin outlet to the crusher. The method for determining the coal blend ratio is as follows: - A method of measuring the coals before blending (for example, on the conveyors 1a and 1b in FIG. 1), calculating an average value (weighted average value) from the measured values ​​of each coal, and increasing or decreasing the amount of each coal cut out from the coal bin based on the measured values ​​of each coal so that the average value falls within a target range of the constituent components of the pulverized coal; and - A method of measuring the amount of each coal discharged from the coal bin after blending the coals (for example, on the transport conveyor 1c in FIG. 1) and increasing or decreasing the amount of each coal discharged from the coal bin based on the amount of each component of each coal that has been separately determined (the analysis value of each coal when it is received, the amount of each component of each coal measured at a position upstream of the coal bin outlet, etc.) so that the measured value falls within a target range of the amount of each component of the pulverized coal; Examples include: For example, when the amount of coal components is measured at the above-mentioned position (1) on the transport conveyor leading from the coal bin outlet to the crusher, the net change in the amount of coal components (i.e., the change actually occurring on site) can be accurately determined, taking into account not only the change over time in the amount of coal components but also the error from the set value for the amount of coal cut from the coal bin.

[0027] (Application to input values ​​of blast furnace mathematical model) In one embodiment, a blast furnace operation simulation is performed using the measurement results of the amount of pulverized coal / coal constituents as an input value of a blast furnace mathematical model. In this case, it is preferable that the measurement position is close to the blast furnace, and from this viewpoint, it is preferable to perform the measurement at the position (2) while the pulverized coal is air-transported from the pulverizer to the distributor. The input value may be the result obtained by the measurement as it is, or as an average value for each preset time as described above. In addition, since the average composition of pulverized coal is generally input to the blast furnace mathematical model, it may be preferable to measure the average composition of the mixture at the position (2). When the amount of pulverized coal / coal constituents is measured at a position closer to the blast furnace, the effect of the time lag from the measurement to the blast furnace injection is small, so that a precise simulation can be performed by directly using the measurement results as an input value of the blast furnace mathematical model. EXAMPLES

[0028] The following examples further illustrate exemplary embodiments of the present invention, but the present invention is not limited to these examples.

[0029] [Example 1] Two types of coal having the amounts of constituent elements shown in Table 1 below were used as raw materials for pulverized coal. Pulverized coal was produced using blast furnace pulverized coal injection equipment with the configuration shown in Figure 1, and the pulverized coal was injected into a blast furnace. Simulation tests were conducted under the following conditions to examine the changes in the C content and RAR over time in the coal.

[0030] [Table 1]

[0031] Coal A was carried into raw coal yard 101a of blast furnace pulverized coal injection equipment 10 shown in FIG. 1, and coal B was carried into raw coal yard 101b. Then, coal A was stored in coal bin 102a and coal B was stored in coal bin 102b. Then, each coal was cut out from the coal bin, transported by conveyors 1a and 1b, and blended to obtain coal A: coal B = 50:50 (mass ratio), then transported by conveyor 1c and pulverized by pulverizer 103 to obtain pulverized coal. The pulverized coal was transported to distributor 109 via bag filter (not shown), hopper 104, transfer tank 105, bag filter (not shown), hopper 106, adjustment tank 107, and supply tank 108, and was injected into the blast furnace from blast furnace tuyeres 110.

[0032] A neutron beam component analyzer was placed on the transport conveyor 1c to measure the C content of the coal (i.e., a mixture of coal A and coal B) flowing on the transport conveyor 1c. The measurement interval was 1 minute, and the total measurement time was 12 hours.

[0033] The average value of the C content in coal obtained by the above measurement was calculated every 60 minutes, and the blend ratio of coal A:coal B was finely adjusted every 60 minutes so that the average value was constant. Specifically, based on the increase or decrease over time of the average value calculated every 60 minutes, if the average value increased, the ratio of coal A, which has a relatively high C content among coal A and coal B, was reduced, and if the average value decreased, the ratio of coal A was increased, thereby adjusting the blending ratio (mass basis) of coal A to the total of coal A and coal B within the range of 50%±5 to 15%. FIG. 2 is a diagram showing the time-dependent variation of the C content in coal in Example 1. FIG. 2 shows the measured value, the moving average value every 60 minutes calculated from the measured value, and the average value over the total measurement time (i.e., 12 hours) calculated from the measured value. FIG. 3 is a diagram showing the time-dependent variation of the RAR (reducing agent ratio) calculated from the C (carbon) content shown in FIG. 2, and shows the value calculated from the measured value of the C content shown in FIG. 2 and its moving average value every 60 minutes. The RAR is calculated by using the influence coefficient of the RAR fluctuation, which is calculated in advance by heat and mass balance calculation when the C content in coal fluctuates. Specifically, it is assumed that the pulverized coal ratio increases by 2 kg / t when the C content in coal decreases by 1%, and that the pulverized coal ratio decreases by 2 kg / t when the C content in coal increases by 1%.

[0034] [Comparative Example 1] Based on the component analysis using a neutron beam component analyzer, but without adjusting the coal blend ratio, the same procedure as in Example 1 was performed to examine the changes over time in the C content and RAR in the coal. The results are shown in Figures 4 and 5.

[0035] Comparing Example 1 (FIGS. 2 and 3) with Comparative Example 1 (FIGS. 4 and 5), in Example 1, by fine-tuning the coal blend ratio based on the measured value of the C content in the coal obtained by neutron beam component analysis, it was found that the fluctuation over time of the C content was reduced compared to Comparative Example 1, and therefore the fluctuation over time of the RAR was reduced. More specifically, in Comparative Example 1, the measured values ​​of the C content ranged from about 70% to about 92%, the moving average value every 60 minutes ranged from about 80% to about 87%, the measured values ​​of the RAR ranged from about -25 kg / t to about 18 kg / t, and the moving average value every 60 minutes ranged from about -5 kg / t to about 7 kg / t, whereas in Example 1, the measured values ​​of the C content were within the range of about 76% to about 92%, the moving average value every 60 minutes ranged from about 81% to about 84%, the measured values ​​of the RAR were within the range of about -12 kg / t to about 20 kg / t, and the moving average value every 60 minutes ranged from about -3 kg / t to about 5 kg / t.

Claims

1. A method for operating a blast furnace, comprising measuring the amount of at least one of the components of pulverized coal injected from a blast furnace tuyere and the components of coal that is a raw material for the pulverized coal at a position between an outlet of a coal bin that stores the coal and an inlet of a distributor that distributes and supplies the pulverized coal to the blast furnace tuyere, The method of operating a blast furnace, wherein the measurements are performed at time intervals of 240 minutes or less.

2. The method for operating a blast furnace according to claim 1 , wherein the measurement is performed by neutron beam component analysis or laser-induced breakdown spectroscopy (LIBS).

3. A method for operating a blast furnace, comprising measuring the amount of at least one of the components of pulverized coal injected from a blast furnace tuyere and the components of coal that is a raw material for the pulverized coal at a position between an outlet of a coal bin that stores the coal and an inlet of a distributor that distributes and supplies the pulverized coal to the blast furnace tuyere, A method for operating a blast furnace, wherein the measurement is performed by neutron beam component analysis or laser-induced breakdown spectroscopy (LIBS).

4. The method for operating a blast furnace according to any one of claims 1 to 3, further comprising performing a blast furnace operation simulation using the results obtained by the measurement as input values ​​for a blast furnace mathematical model.

5. A method for operating a blast furnace, comprising measuring the amount of at least one of the components of pulverized coal injected from a blast furnace tuyere and the components of coal that is a raw material for the pulverized coal at a position between an outlet of a coal bin that stores the coal and an inlet of a distributor that distributes and supplies the pulverized coal to the blast furnace tuyere, A method for operating a blast furnace, comprising: performing a simulation of blast furnace operation by using the results obtained by the measurement as input values ​​for a mathematical model of the blast furnace.

6. The method for operating a blast furnace according to claim 4 or 5, further comprising: calculating an average value of the results obtained by the measurement for each preset time period; and using the average value as the input value.

7. The component to be measured is one or more selected from the group consisting of C (carbon), H (hydrogen), O (oxygen), N (nitrogen), S (sulfur), ash, volatile matter and moisture. The method for operating a blast furnace according to any one of claims 1 to 6.

8. The blast furnace operation method according to any one of claims 1 to 7, further comprising adjusting a blend ratio of a plurality of types of coal so that the pulverized coal injected from the blast furnace tuyere has a predetermined amount of constituent components based on the results obtained by the measurement.

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