JPS6130638A - Method for measuring temperature of molten body in copper converter - Google Patents

Abstract

PURPOSE:To eliminate trouble due to fume generated in a converter, etc. by covering the outer end of the tuyere of a copper converter with a transparent body, regulating the flow rate of gas blown into a molten body in the converter to Mach 1 or above in the standard state at the tip of the tuyere, and measuring the temp. of the molten body with a noncontact type thermometer through the transparent body. CONSTITUTION:A transparent body 12 is fixed in a cap 7 on a tuyere box 1 of a copper converter to form a peeping window. A radiant pyrometer 13 is placed at a position close to the transparent body 12 at the outside of the converter and on the extension of a tuyere pipe 3. Air is sent to the tuyere from a blast pipe 2 so that the flow rate (Nm/sec) of the air blown into the molten body 8 under high pressure is regulated to Mach 1 or above in the standard state at the tip of the tuyere pipe 3, and the temp. of the molten body 8 is measured with the pyrometer 13 through the transparent body 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for measuring the temperature of a hot solution in a copper converter.

[Conventional technology]

Conventionally, to measure the temperature of the solution in a copper converter, an immersion thermometer with a protection tube or a consumable immersion thermometer was used to measure the temperature of the solution in the converter. Methods such as a type optical pyrometer, radiation pyrometer, etc. are installed from near the furnace mouth toward the melt surface.

However, when using a protection tube, the lifespan of the protection tube is short due to thermal shock, mechanical shock, or erosion due to melting, it cannot withstand continuous use for a long period of time, and it is expensive. Consumable thermometers have drawbacks such as inability to perform continuous measurements and high cost. In non-contact optical pyrometers, radiation pyrometers, two-color thermometers, etc., there is a high concentration of dust, fume, etc. between the solution and the measuring instrument, and the concentration changes from moment to moment, resulting in poor accuracy. The drawback was that good measurements could not be made.

On the other hand, in the operation of a copper converter, air or oxygen-enriched air is blown into a molten chain mainly consisting of copper, iron, and sulfur through multiple tuyere openings below the liquid surface, and the iron content is turned into slag. The sulfur content is removed as SO gas to produce blister copper, which is approximately 99% copper. The operating conditions conventionally adopted in this copper converter are a blowing pressure of 0.6 to 1, 2 kg/bm2 (gauge pressure), and a gas flow rate in the tuyere pipe of 60 to 140 kg/bm2 (gauge pressure).
The flow rate is approximately Nm/sea (flow rate under standard conditions). Under these conditions, the behavior of the air or oxygen-enriched air blown into the solution is unstable, the airflow becomes bubbling, and air bubbles are frequently blown back into the tuyere.
At this time, the solution enters the tuyere pipe and the tuyere is blocked.

For this reason, conventional practical-scale copper converters require a so-called punching operation to intermittently punch the tuyeres. The rod is punched manually or by using a punching device equipped with a punching rod, which requires a lot of labor or requires high equipment costs. Theoretically, it is possible to observe the solution in the furnace through the clean blown gas in the mouth, but in reality, it is possible to observe the leakage of high-pressure blown gas from the tuyere end and the gap between the tuyere end opening and the punching rod. Observation is extremely difficult due to the narrow space and the scattering of high-temperature materials when the punching rod is pulled out, and the opening end of the tuyere inside the furnace will be blocked unless the punching rod is used to break through the hole. Even if a viewing window was provided, it would not be practical at all. [Problems to be solved by the invention] The present invention solves the above-mentioned drawbacks and problems, and uses a non-contact type thermometer to measure intermediate fumes, etc. The purpose is to be able to measure the temperature of a solution without being disturbed by

[Means for solving problems]

As a result of various studies, the inventors determined that the flow rate of the gas injected into the solution from the tip of the tuyere should be set to a standard value in order to prevent clogging of the tuyere during converter operation and eliminate the need for punching, which was previously considered essential. Matsuha 1 or more (3
4.0Nr11/8θC or higher), blowing pressure 2 to 3.5
He discovered that this could be achieved by setting the tuyeres to 1% and filed a patent application No. 58-222884, but when carrying out such operations, the conventional tuyere box was modified and the opening end of the tuyere inside the furnace was changed. By closing the opposite end with a transparent body, the melt inside the furnace can be observed from outside the furnace through this transparent body during the ventilation process, and a non-contact thermometer is installed outside the furnace to monitor the inside of the furnace. It is designed to measure the temperature of the solution, and in the case of a large converter, only a few of the approximately 50 tuyeres that can measure the temperature of the solution are sufficient, so it is possible to measure the temperature of the solution. High-temperature air may be applied to only some of the tuyeres.
Alternatively, all the tuyeres may be blown at high speed and transparent bodies may be attached to only some of them.

The structure of the tuyere used in the method of the present invention will be explained below with reference to the drawings in comparison with a tuyere of conventional structure. Fig. 2 is a cross-sectional view showing the structure of a conventional tuyere, in which 1 is a tuyere box, 2 is a compressed gas blast pipe, 3 is a tuyere pipe in front of a steel pipe, and the converter body 4...
One end of the refractory brick 5 is opened into the furnace.

Reference numeral 6 denotes a steel ball, which serves as a spherical valve to prevent high-pressure gas from leaking from a portion of a cap 7 provided on the opposite side of the opening end of the furnace on the extension of the tuyere pipe 3 of the tuyere box 1. ing. As a result, the high-pressure gas sent from the blast pipe 2 presses the steel ball 6 against the inside of the cap 7, so that almost the entire amount is blown into the converter melt 8 through the tuyere pipe 3. However, at the conventional flow rate in the tuyeres, the tuyeres are successively closed, making a punching operation necessary. FIG. 3 shows a state in which the punching rod is inserted. When the punching rod 9, which is slightly thinner than the inner diameter of the tuyere, is inserted from the cap 7, the steel ball 6 is pushed by the punching rod 9, and the punching rod 9 is pushed into the pocket of the tuyere box. 10, and is placed on the punching rod 9. Although the punching rod 9 breaks the blockage of the tuyere pipe 3, the blown gas leaks from the gap 11 between the punching rod 9 and the cap 7.

In the method of the present invention, since the tuyere flow velocity is set to 1 or higher, the tuyere does not become clogged and there is no need to use the punching rod 9. Therefore, the conventional tuyere box 1 is modified as shown in FIG. Then, a transparent body 12 was attached to the cap 7 of the tuyere box 1 and closed to serve as a viewing window. In this way, dust inside the tuyere box and tuyere pipe can be removed from outside the furnace.
Since the solution in the furnace can be directly observed through clean gas that does not contain fumes, the temperature of the solution in the furnace can be continuously measured by placing, for example, a radiation pyrometer 13 near the transparent body 12 on the extension line of the tuyere. If this pyrometer is fixed to the tuyere box on the tuyere extension line, it can cope with slight tilting of the converter during operation, and it can also be used to prevent the converter from blowing air, such as when discharging slag or blister copper. It is convenient to have a thermometer that can be easily removed since it is not necessary to measure the temperature when tilting it by nearly 90 degrees from the original state.

Transparent body 12 attached to the cap 7 of the tuyere box
The material is not limited to heat-resistant glass, but may be made of any material that can withstand temperature and blowing pressure and has good transparency, such as quartz, crystal, or heat-resistant plastic. Matsuha 1 flow rate
In order to maintain this level, it is preferable to set the air blowing pressure to 2 or more. This is because the blowing pressure is 0.6 like in a conventional converter.
~1.21cg2 blood and tuyere flow rate is 60-1 under standard conditions
40 Nrrv/sθC, the air flow rate is too high with the tuyere diameter and number of tuyeres, so generally the tuyere diameter must be made thinner or the number of tuyeres must be reduced.In order to overcome the air blowing resistance, the air blowing pressure must be increased. It is preferable to leave it there.

(Function) The present invention has made it possible to continuously measure the temperature of the solution inside the converter furnace, so even if the temperature does not indicate the true temperature, it is possible to at least know the change in relative temperature.
Using this, it is possible to control the charging amount for cold opening and minimize fluctuations in the solution temperature.

Since the reaction in the converter is an exothermic reaction, there is excess heat, and generally scraps, smoke, etc. are charged from the furnace opening during operation to maintain the molten metal within an appropriate temperature range. If the temperature is too high, the bricks will be severely damaged, and if the temperature is too low, the separation of the wrinkles and the cracks will be poor and the solution will be scattered more, which is undesirable. However, until now it has been impossible or difficult to measure the temperature continuously, and large fluctuations in the temperature of the molten metal have been unavoidable. Powdered smoke ash can be blown into the molten metal while controlling its amount to avoid fluctuations in the temperature of the molten metal.

(Example) PS converter with a plating capacity of 6 t/time (brick internal dimension 1.5 mφ
1.7 mL) with four tuyeres with an inner diameter of 21 m/m, and
U53.5% by weight of a and Ot were charged and the oxygen concentration was 34.
% oxygen-enriched air was blown at a rate of 1750 Nm/H, the flow velocity at the tip of the tuyere 1 was 351 N+r4/sθC
(Matsuha 1.03). Silicate ore was added as a solvent and the forging period was divided into two times and air was blown for 65 minutes.

After slow flowing, air is blown during the steelmaking stage to produce powdered flash smelting furnace smoke (Ou
28.6%, 87.8%, Fe 7.5%, SiO5,
7%) 550 to 9 cold open, blowing air at a rate of 5 to 80 ky for 1 minute through three tuyere whose tuyere caps are transparent and not closed for 3 to 42 minutes after the start of air blowing during the copper making period. The temperature of the solution was blown into a predetermined pattern. Figure 4 shows the fluctuations in the radiation pyrometer reading at that time. This copper making period ended in 60 minutes.

[Comparative example]

0u54.1wt% wrinkles 6.1 in the same converter as in the example
200 kg, 10 minutes after the start of air blowing in the copper making period, 3 minutes after the start of air blowing in the copper making period. 100 later
After 20 minutes, 200 kg (500 kg in total) of cold open air was charged through the furnace mouth, and the temperature was measured from the tuyere using a radiation pyrometer. The results are also shown in FIG.

(Effects of the Invention) As is clear from Fig. 4, when the cold opening is charged intermittently from the furnace mouth as in the conventional method, the temperature of the melt in the furnace changes significantly. It has a wide range of uses, not just for measurement, but also for providing feedback to the appropriate charging amount for cold opening as mentioned above, making it possible to stabilize the temperature of the molten metal in the converter. .

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a tuyere of a copper converter for carrying out the method of measuring the solution temperature of a copper converter according to the present invention, Fig. 2 is a cross-sectional view of a tuyere of a conventional copper converter, and Fig. 3 is a cross-sectional view of a tuyere of a conventional copper converter. Fig. 2 is a cross-sectional view showing the state of the tuyere during punching, and Fig. 4 is a diagram showing the solution temperature control state when operating using the measuring method of the present invention and during conventional operation. . 1.Tuyere box, 2.Blow pipe, 3.Tuyere pipe, 1
．．・・Converter furnace body, 5.・Refractory bricks, 6.・Steel balls, 7.・
Cap, 8. Converter melt, 9. Punching rod, 10. Pocket part, 11.
・Gap, 12...Transparent body, 13...Radiation pyrometer.

Claims (1)

[Claims] (1) At least a part of the tuyere of the copper converter is closed at the outside end of the tuyere with a transparent material, and the flow rate at the tip of the tuyere of the gas blown into the solution is set to the standard state flow rate (Nm/sec). ), a method for measuring the temperature of a solution in a copper converter, characterized in that the temperature of the solution in the furnace is measured with a non-contact thermometer by blowing air into the tuyere with a Matsuha of 1 or more, and through the transparent body.