KR910006222B1 - Apparatus for measuring silicon amount in molten iron - Google Patents

Abstract

No content.

Description

Silicon amount measuring device in molten iron

1 to 3 are cross-sectional views each showing an embodiment of the present invention.

4a, b, c are cross-sectional views showing embodiments of introduction means;

5 is a cross-sectional view showing the same embodiment of the present invention.

6 is a graph showing the experimental results.

* Explanation of symbols for main parts of the drawings

A: device body B: introduction means

C: temperature drop means 1: cylinder

2: holding battery member 3: molten iron side electrode

4: lead wire side electrode 5: insulated tube

6 coolant 7 bulge

8: small diameter part 9: molten iron side thermocouple

10: introduction charter side thermocouple 11: sampling chamber

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for measuring the amount of silicon in molten iron, and to a silicon amount measuring device capable of easily and quickly and accurately measuring the amount of silicon in molten iron generated in a blast furnace when operating at an ironworks, for example. will be.

Accurately and quickly detecting and measuring element contents such as carbon, oxygen, silicon, phosphorus, and sulfur in molten steel in the steelmaking process is carried out by removing the respective elements or quickly performing a refining process to control the steelmaking industry. Since it is extremely important for shortening, the measuring method and device of each element have been studied.

In particular, in the previous steelmaking process leading to the steelmaking process such as dephosphorization and desulfurization, it is extremely important to accurately grasp the silicon content in the molten iron during the preliminary molten metal pretreatment process such as dephosphorization and desulfurization. .

As a method and apparatus for measuring silicon content, which has been used in the conventional iron making process, a so-called thermoelectric power method for specifying silicon content by measuring the thermoelectric power generated between a pair of electrodes and a sample is known.

However, according to this conventional measuring method, after the sample is taken and solidified to give a temperature difference between the two electrodes due to the generation of thermoelectric power, the sample needs to be partially reheated, and the temperature difference between the two electrodes is balanced. There is a problem that it is difficult to maintain it. In addition, since slug adheres to the surface of the sample and it is considered that it is not the original composition, both electrode setting parts need to be cut and polished with a grinder or the like. As a result, the measurement takes a long time because the measurement is performed via a cumbersome process such as setting and maintaining the temperature difference between the two electrodes by sampling, solidification, cutting, polishing, and reheating.

In addition, according to this measuring method, the crystal structure in the sample at the time of solidification may change significantly due to the slight change in the shape, dimensions, and sampling conditions of the sample. The problem of lack of reliability of the value remained.

As another conventional example, as indicated in Japanese Patent Laid-Open No. 45 (1970) No. 36280, a sample collected in the cylinder is placed by placing a cooling plate at the bottom of the cylinder made of sand and other heat-resistant materials. By cooling this sample from the bottom with a cooling plate, a temperature gradient is generated from the bottom to the top of the sample, and a temperature difference is generated between the two electrodes previously installed through the side wall of the cylinder. The thermoelectric power generated between the sample and the sample is measured.

However, even with this measuring method, the temperature difference between the two electrodes, that is, the temperature gradient of the sample in the cylinder is not limited only by cooling by the cooling plate, and therefore, between the two electrodes having a short and long distance from the cooling plate. It is difficult to maintain the equilibrium temperature difference, and there is a problem that the thermoelectric power value also changes according to the change of the temperature difference, which affects the accuracy of the measurement. The problem that the measurement time is long has been solved since it is introduced into a cooling vessel made of a prepared cylinder and a cooling plate, and the measurement time is long.

The present invention has been developed to solve the above-described conventional method for measuring the amount of silicon, defects left in the apparatus, and the problem is that one of the electrodes is placed in the molten molten iron, and the other is the temperature drop. By placing the sample in a container holding the means or in the introduction charter in the introduction means for introducing the molten iron into the container, the sample is taken as in the conventional measuring method and placed in a separately prepared container, and the positive electrode is set on the collected sample. It does not require any troublesome means of measuring the thermoelectric power by reheating and then reheating or giving a temperature difference between both electrodes during the solidification, and it is made to measure the amount of silicon in the molten iron simply and quickly.

Hereinafter, the present invention, the present invention has a means for introducing the molten iron into the device by immersing in the molten iron in the collecting means of the elongated semi-cylindrical grooves, pots, top feed cars, etc. The temperature drop means for imparting the molten iron and the temperature difference is provided by the introduction means and the vehicle body in relation to the introduction means, and the electrodes are placed in the molten iron and in the introduction molten iron in the apparatus or introduction means. Is to measure the amount of silicon in the molten iron by measuring the thermoelectric power generated in the molten iron, and the apparatus includes a sampling chamber which introduces molten iron in the collecting means, and includes electrode bases, lead wires, thermocouples for temperature measurement, etc. It has the function of maintaining the preservation, means of introduction means literally the tube to introduce the molten iron into the collection chamber of the above-mentioned device, It shall collect, as well as function as a conduit of the Interior shall have the ability to help to maintain the conservation charters including within the cylinder.

The temperature lowering means is for cooling the introduction molten iron so as to give a predetermined temperature difference to the introduction molten iron and the molten iron taken into the apparatus sampling chamber and / or the introduction means as the introduction means.

Therefore, this temperature drop means may be provided in or outside the aforementioned apparatus collection chamber and / or introduction means, or the sampling chamber or introduction means itself may be configured as the temperature drop means.

The electrode is installed by placing one side of the molten iron in the sampling means and the other side in the introduction molten iron cooled as the above-described temperature drop means. Both electrodes are separately attached or attached using a common supporting member such as an electric device. Shall be.

According to the silicon amount measuring device in the molten iron of the present invention configured as described above, in the thermoelectric power method for measuring the thermoelectric power generated between the positive electrode and the sample and thereby determining the amount of silicon, The two electrodes are not set and the temperature difference between the two electrodes is not measured, and one of the two electrodes is taken out of the molten iron, and the other is taken into the apparatus collection chamber or the introduction means in which the other is cooled, and in the introduction molten iron cooled as a temperature drop means. It is not necessary to collect the sample molten iron in the furnace by setting it, and it is simply and quickly contained by dipping in the molten iron in the collecting means such as the slot of the long and semi-cylindrical which collects the molten iron from the blast furnace, the pot and the top feed car. The amount of silicon is measured and further, it is possible to drastically shorten the steelmaking industry.

On the other hand, another invention of the present application has a means for immersing in the molten iron and introducing the molten iron into the sampling chamber of the apparatus, and a means for introducing a temperature drop for imparting a temperature difference between the molten iron and the molten iron. It is made by placing the electrode and the thermocouple in the molten iron and in the molten iron inside the apparatus or introduction means, respectively.The amount of silicon in the molten iron is determined by measuring the thermoelectric power generated between the two electrodes. In addition, the temperature difference between the two electrodes in measuring the amount of silicon is measured, and the functions and configurations of the apparatus, the introduction means, the temperature drop means, the electrode, and the like are the same as those of the specific invention described above. In addition to the fact that the amount of silicon contained in the molten iron can be measured simply and quickly in the same manner as the specific invention described above, By measuring the temperature in the molten iron flow rate measuring and at the same time as close to the electrodes for measuring the thermal electromotive force value, checking the temperature difference between the electrodes it is obtained a further higher accuracy than the measurement of silicon content value.

In the present invention, a sampling chamber is provided in the apparatus so that the sample can be used for physical and chemical analysis such as luminescence analysis.

Next, both inventions of the present application will be described according to specific embodiments. FIGS. 1 to 3 show embodiments of a specific invention, and FIG. 1 is made of a heat-resistant material such as a paper pipe. A heat-resistant cylinder 1 such as ceramic as the introduction means B is fixed at the lower end of the apparatus main body A having the device body A as a storage battery member 2 such as refractory cement, and the storage battery member 2 is introduced. The molten iron side electrode 3 protrudes from the lower end surface of the apparatus main body A and is fixed and installed as the battery retaining member 2. The side electrode 4 is a substantially central portion in the cylinder 1, which is an introduction means, and is positioned from the outer end of the holding member 2 as a temperature drop means to be located deep inside. Hard to be dissolved by molten iron Operating like a high melting point, for example, by using a carbon, Mo, W, surge mid (cermet) and the like.

In Fig. 5, an insulated tube is shown.

According to this embodiment, the electrode 3 is placed in the molten iron by immersing the apparatus body A in the molten iron collected from the blast furnace, and the molten iron rising through the cylinder 1 is cooled as the temperature lowering means C. In this case, as the introduction molten iron in the state of charge in the cylinder 1, a temperature difference is generated between the molten iron and the molten iron and the thermoelectric power is generated between the electrodes 3 and 4, and this is measured as a voltmeter (V). .

Next, FIG. 2 shows that the coolant 6 is provided outside the cylinder 1 as the introduction means B by applying it to the holding member 2, which is described as the temperature drop means C. FIG. An embodiment in which the coolant 6 is fitted to the upper end of the cylinder 1 and is fixed. When the low melting point metal is used as the coolant 6 in the embodiment of FIG. 3, it is used as a molten iron that rises inside the cylinder 1. During the melting of the coolant 6, while the coolant made of the low melting point metal coexists as a solid and a liquid, the temperature is maintained at the melting point of the low melting point metal. Since the temperature difference is maintained at the temperature, the temperature difference between the molten iron and the introduction molten iron, that is, the temperature difference between the two electrodes 3 and 4 can be maintained in an equilibrium state so that the accuracy can be increased.

In addition, the low melting point metal used for the coolant 6 is preferably a pure metal having a low melting point, which is dissolved as a molten iron so that no component change occurs in the introduction molten metal and does not react with Mo or the like used in the electrode 4. It is a condition and it is assumed that Pb or Bi is used.

As another embodiment, for example, in FIG. 3, a part or the whole of the cylinder 1 itself is used as the coolant 6, and the cylinder 1 also has the introduction means B and the temperature lowering means C. It is possible.

In addition, when the cylinder 1 is simply used as the introduction means B, not only the cylindrical shape shown in FIGS. 1 to 3 but also the bulge 7 is formed near the upper part as shown in FIG. 4A. It is possible to control the cooling rate of the introduction charter in the cylinder, and again, as shown in FIG. 4B, by forming a small diameter portion 8 near the lower part, the flow of the introduction charter flowed into the cylinder 1 again flows out. It can prevent.

In addition, as shown in FIG. 4C, it is also possible to form a conventionally known pin sampler in which the upper and lower ends of the cylinder 1 are sealed and the inside is vacuumed.

Next, as a specific embodiment of another invention of the present application, as shown in FIG. 5, the molten iron side thermocouple 9 is protruded downward from the holding member 2, and the electrode 4 in the cylinder 1 is provided. ), The introduction molten iron side thermocouple 10 is provided close to the other side, and the other configuration is the same as that of the embodiment shown in FIG.

The thermocouples 9 and 10 can also be applied to the second and third embodiments described above, and the molten iron side thermocouple 9 together with the molten iron electrode 3 has the original composition, It is necessary to be immersed in the position which displays a temperature, and the introduction ship side thermocouple 10 shall be installed as close as possible to the electrode 4. As shown in FIG.

Thus, the molten iron is measured by measuring the molten iron temperature and the molten iron temperature in the measurement of the thermoelectric power generated between the electrodes 3 and 4 by providing thermocouples 9 or 10 in the molten iron side and the induction molten iron, respectively. It is possible to increase the reliability of the measured thermoelectric power value by measuring the thermoelectric power in a state where the temperature difference between the molten iron and the lead wire is accurately understood.

In addition, as an experimental example of the present invention, an apparatus body in which Mo is used for electrodes 3 and 4, and thermocouples 9 and 10 are additionally installed under the same conditions as described above in the embodiment of FIG. A) is used, and the thermoelectric power value is measured while the apparatus main body is immersed in the molten iron and the temperature difference between the molten iron and the molten iron in the cylinder 1 is set at 400 ° C. The results of this experiment are shown in FIG. As shown in the graph, it was found that the measured value substantially coincided with the curve in the figure, and the thermoelectric power measured value indicated the amount of silicon displayed on the horizontal axis.

The experimental results show that the silicon content decreases as the thermoelectric power value increases, and the silicon content change is large with respect to the change in the thermoelectric power value, especially 0.2- around the content of 0.3-1.0%. Even if a slight change of the 0.4mV thermoelectric power value indicates that the silicon content changes by 0.1-0.25%, this means that the thermoelectric power measurement requires a highly accurate measurement value.

According to the specific invention in the present application made as described above, a means for introducing molten iron into the apparatus is provided, and a temperature drop means for providing a predetermined temperature difference between the molten iron and the molten iron is provided in relation to the introducing means. In addition, the measuring device is arranged by placing electrodes in the molten iron and in the molten iron in the apparatus or introduction means.In actual measurement, the measurement is carried out in the molten iron in the collecting means such as grooves, pots and toe-feed cars of elongated semi-cylindrical bodies. By immersing the device itself, one electrode can be positioned in the molten iron and the other electrode can be positioned in the introduction molten iron introduced into the apparatus and / or into the introduction means as an introduction means, and the introduction chart is a temperature drop means. As a result of cooling to impart a temperature difference between the molten iron and the thermoelectric power generated between the two electrodes Since the content of silicon in the molten iron can be determined by measurement, the molten iron is taken as a sample and placed in a separately prepared container to be solidified, cut, polished, and then reheated or a temperature difference is generated between both electrodes during solidification. Compared to measurement, it is unnecessary to collect molten iron, flow into a separately prepared container, solidify or cut, grind, reheat, and so on. By simply immersing in the molten iron in the means, it is possible to quickly measure the thermoelectric power, that is, the silicon content, and to measure the thermoelectric power value according to the slight change of the sample size, shape, and sampling conditions. No error occurs, and in the present invention, the temperature difference between the molten iron and the molten iron It is possible to prevent non-uniformity in the thermal electromotive force obtained from the change in the temperature difference between from being maintained in equilibrium compared to the measurement method by the conventional sampling the electrodes.

In addition, according to the second invention, in addition to the effects of the specific invention described above, by measuring the temperature of the portion close to the electrode of the molten iron and the introduction molten iron, the measurement of the thermoelectric power, that is, the measurement of the amount of silicon in a state where the temperature difference between the two electrodes is accurately known In doing so, the accuracy of the measured thermoelectric power value can be increased.

Claims (2)

A means (B) for immersing in the molten iron and introducing the molten iron into the apparatus, and installing a temperature lowering means (C) for introducing a predetermined temperature difference between the molten iron and the molten iron into the introduction means itself or in relation to the introduction means. In addition, the apparatus for measuring the amount of silicon in the molten iron which arranges the electrodes (3) and (4), respectively, in the molten iron and in the introduction molten iron in the apparatus or introduction means, and determines the amount of silicon by measuring the thermoelectric power generated between the two electrodes. . A means (B) for immersing in the molten iron and introducing the molten iron into the apparatus, and installing a temperature lowering means (C) for introducing a predetermined temperature difference between the molten iron and the molten iron in the introduction means itself or in relation to the introduction means. In addition, by placing electrodes 3, 4 and thermocouples 9, 10, respectively in the molten iron and in the molten iron in the apparatus or introduction means, by measuring the thermoelectric power generated between the two electrodes, A silicon amount measuring device in a molten iron, characterized in that the amount of silicon is determined and the temperature difference between the two electrodes when measuring the amount of silicon is measured.

Images