JPH0452411B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for measuring the properties of sintered ore, in which each composition of the macrostructure and microstructure of sintered ore is quantified, and these quantities are used to determine the reducibility, reduction powderability, etc. The objective is to quickly and accurately measure the properties of sintered ore.

It is known that the physical properties of sintered ore are closely related to the sintered ore structure, and for this reason, various property measurement methods focusing on sintered ore properties have been proposed. Typical examples include the so-called Permagnag method, in which a sample is placed in a cylinder equipped with a coil, and changes in the resonant frequency that occur depending on the proportion of magnetite contained in the sample are used, and the magnetic susceptibility of the sample is used. There are several methods to do this, and all of these methods have in common that only iron oxides such as hematite and magnetite can be quantified. However, it is thought that the physical properties of sintered ore do not simply depend on the amount of iron oxide, but also on the presence of other structures such as calcium ferrite, slag, pores, and even secondary hematite in hematite. It is questionable whether the above method, which does not involve quantification, can serve as a sufficient guideline for management of actual operations. In addition, according to the inventors' studies, the physical properties of sintered ore are closely related not only to its microstructure but also to its macrostructure, including this macrostructure. It has been found that without an overall analysis of the tissue, it is not possible to adequately measure its physical properties. However, all of the conventional measurement methods, including the above methods, target the microstructure of sintered ore, and that is, only a part of the composition within that structure. There is still no example of focusing on the microstructure, analyzing it, and applying it to measuring the properties of sintered ore.

The present invention was devised in view of the current situation, and its basic features are as follows. First, the specified measurement range of the sintered ore sample is subdivided into small sections to obtain images of the microstructure for each section, and the microstructure ratio is measured based on the difference in reflectance between the images of each section through image processing. , magnetite,
In addition to determining the microstructure of minerals represented by compositions such as calcium ferrite and slag,
The microstructure ratio of the entire measurement range is determined from the tissue ratio of all these sections. On the other hand, in determining the macrostructure ratio, which is divided into the original ore part where the ore does not melt and retains its original shape, the sintered part where the ore melts and solidifies once, and the macropores with a diameter of 250μ or more, For each section, from the amount of hematite (H), the amount of magnetite (M), the amount of calcium ferrite (C), and the amount of slag (S), the section has an area ratio of (H + M + C + S) 10% to the section area. is the pore area, (H+M+C+S)>10%
Of which (H/(H+M+C)) 35% and (H
+M)/(H+M+C) 55% section is former mining department,
The other sections are determined to be sintered parts, and the macrostructure ratio of the entire measurement range is determined from the structure ratio of all these sections. Then, the sintered ore properties are measured based on the relationship between the composition ratio in the macrostructure and microstructure and the sintered ore properties, which have been determined in advance.By doing this, the sintered ore structure can be measured. It becomes possible to quickly and accurately measure properties based on overall discrimination and quantification.

The physical properties of sintered ore, such as room temperature strength, hot strength, reducibility, and reduction pulverizability, are strongly correlated not only with the microstructure of hematite and magnetite, but also with the macrostructure of the original ore and macropores. As described above, the present invention involves quantifying the structures and pores of both the microstructure and macrostructure of sintered ore. The present inventors have already proposed a method of measuring the properties of sintered ore by quantifying each composition of both the microstructure and macrostructure of sintered ore, similar to the present invention. In this method, both the macrostructure and the microstructure were imaged, and the tissue ratio was obtained by processing each image. In contrast, the present invention is characterized by omitting macrostructure imaging and image processing and quantifying microstructures and macrostructures based only on microstructure images, thereby speeding up measurements. can do.

In the present invention, first, imaging of the microstructure of a sample is performed. Here, microstructures include hematite, magnetite, calcium ferrite, slag,
It means a structure in which micropores with a diameter of less than 250μ can be discerned. Moreover, the macrostructure refers to a structure in which the original ore part, sintered part, and macropores can be distinguished. Imaging of the microstructure defines the measurement range of the sample, subdivides this measurement range into small sections, and is performed for each section. This imaging is performed using an ITV camera or the like through a microscope with a magnification of about 50 to 400 times. To explain in more detail an example of the process up to such imaging, for example, from actual sintered ore,
A sample approximately 10 mm square is sampled, embedded in resin, and diamond polished or equivalently polished. The measurement range is defined as 9 mm x 9 mm, and this is divided into small sections of approximately 250 μ x 250 μ, and each section is imaged.

For each image obtained in this way, the tissue proportion based on the difference in reflectance is measured. In the microstructure, the reflectance of light differs depending on the structure, and hematite, magnetite, calcium ferrite, slag, and pores are identified in order of the highest reflectance, and the area ratio of these for each section is determined.

On the other hand, regarding the macrostructure, the structure ratio is measured from the above-mentioned microstructure ratio. That is, it is determined which structure in the macrostructure each section corresponds to from the composition ratio in the microstructure of each section quantified as described above. The macrostructure of each section is determined as follows from the hematite amount (H), magnetite amount (M), calcium ferrite amount (C), and slag amount (S) measured for each section.

()(H+M+C+S) If it is 10%, it is the stomata.

() (H+M+C+S)＞10%, (H/
(H+M+C)) 35% and (H+M)/(H
+M+C) 55% is former mining department.

() Among (H+M+C+S)>10%, cases other than () are sintered parts.

Then, from the macrostructure of each section obtained in this manner, the proportion of the macrostructure in the entire measurement range, that is, the respective proportions of the original ore part, the sintered part, and the macropores are quantified. As described above, in the present invention, the sample preparation, measurement work, etc. required for actual macrostructure measurement can be completely omitted without actually measuring the macrostructure ratio.

As described above, the composition ratio of the microstructure and macrostructure in the sample is determined, and the sintered ore properties are determined based on the relationship between the composition ratio in the microstructure and macrostructure determined in advance and the sintered ore properties. However, as mentioned above, by obtaining both the micro and macro structure ratios (micro: actual value, macro: estimated value), it is possible to obtain 2, which has a strong correlation with the properties of sintered ore.
Next, the tissue proportion of hematite can be determined.
In other words, the so-called secondary hematite (included in the sintered part in the macro composition), which is hematite excluding the original ore part, that is, the hematite in the original ore, is reduced to magnetite and oxidized to hematite again by sintering. Although there is a strong correlation with the pulverization rate, the reflectance of the secondary hematite is the same as that of the hematite in the original ore, and therefore it is difficult to distinguish between the two by image processing alone, let alone the macrostructure. It's impossible. In the present invention, from the above determined original ore structure and hematite structure in the microstructure,
(Amount of hematite) - (Original ore amount) = (Amount of secondary hematite)
The amount of secondary hematite can be determined by (area ratio). Then, each quantitative analysis value obtained as above, that is, hematite, magnetite, calcium ferrite, slag, and micropores in the microstructure, the original ore part, sintered part, and macropores in the macrostructure, and 2 Next, each physical property of the sintered ore is calculated based on each quantitative analysis value of hematite, and, for example, the reduction rate is calculated based on the quantitative analysis value of the macropores.

Specifically, an automated measurement system is used for the above process. This system is a microscope,
It includes an imaging device and a processing device for performing image processing and a series of calculations based on the image processing, and quantifies each composition through a series of processes from images of the microstructure taken through a microscope and performs physical calculations based on this. Calculate the properties and display them. For this reason, the processing device stores in advance the relationship between each reflectance and each structure component, and finally an index indicating the properties of the sintered ore is determined by calculation according to each structure component.

Figure 1 shows such an automated measurement system, where 1 is a microscope, 2 is a television camera,
3 is a camera controller, 4 is an electronic computer that performs the above calculation processing, 5 is a monitor television, 6 is a hard copy, 7 is a plotter, 8 is a line printer, 9
is a disk file. According to these measurement systems, the image reflected by the microscope 1 is converted into a video signal by the television camera 2, and this is sent to the computer 4. The electronic computer detects each brightness level using pixels divided into approximately 65,000 pixels per field of view, and performs geometric and statistical calculations to determine the proportion of each microstructure and the sintered ore based on this. An index indicating the properties is required. The results of such calculations are displayed on a monitor television, hard copy, plotter, line printer, etc., and the measured data is stored in a disk file, etc. Note that when imaging the sample, the brightness is measured using a standard reflector before and after the imaging, and the reflectance of the tissue is calibrated.

FIGS. 2 and 3 show an example of investigating the relationship between sintered ore structure and properties using the method of the present invention. Of these, Figure 2 shows the relationship between macropore quantitative analysis and reduction rate, and Figure 3 shows the relationship between secondary hematite quantitative analysis value and reduction powdering rate. A strong correlation is observed between the structure and properties of . And in the present invention,
For example, (reduction rate) = a x (macropore quantitative analysis value) (reduction powdering rate) = a x (secondary hematite quantitative analysis value) -b x (original ore quantitative analysis value) + c *However, a, Each physical property is determined by an expression such as b, c...constants.

As described above, according to the present invention, when measuring the properties of sintered ore, not only the microstructure of sintered ore but also the composition of macrostructure and even secondary hematite are used as measurement factors, and each of these structures is Quantification and measurement of sintered ore properties, imaging of the microstructure, quantification of the structure ratio by image processing, and quantification of the macrostructure ratio based on the microstructure ratio to determine the overall structure ratio of the sintered ore. Since we adopted a series of processes to determine the physical properties based on this, we were able to quickly and accurately measure the properties of sintered ore, such as reduction powderability and reducibility. Feedback to actual operations is quick and accurate, and sintered ore with good properties can be produced, so this invention has great industrial effects.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an example of a measurement system used for implementing the present invention. FIG. 2 shows the relationship between macropore quantitative analysis values and reduction rate. FIG. 3 shows the relationship between the secondary hematite quantitative analysis value and the reduction powdering rate.

Claims (1)

[Claims] 1. The specified measurement range of the sintered ore sample is subdivided into small sections to obtain images of the microstructure of each section, and the composition ratio based on the difference in reflectance of each image is measured to determine the hematite, In addition to determining the microstructure proportions represented by compositions such as magnetite, calcium ferrite, and slag, the microstructure proportions of the entire measurement range are determined from the structure proportions of all these sections. In calculating the differentiated macrostructure ratio, for each section, from the amount of hematite (H), amount of magnetite (M), amount of calcium ferrite (C), and amount of slag (S), (H + M + C +
S)≦10% section is stomata, (H+M+C+S)>
Among the 10% sections, sections with (H/(H+M+C))≧35% and (H+M)/(H+M+C))≧55% are determined to be former ore areas, and the other sections are determined to be sintered areas. The macrostructure ratio of the entire measurement range was determined from the structure ratio of all sections, and the sintered ore properties were measured based on the relationship between the composition ratio in the microstructure and macrostructure determined in advance and the sintered ore properties. A method for measuring the properties of sintered ore.