JPS62153140A - Taking out of molten iron from rock wool raw material melt - Google Patents

Abstract

PURPOSE:To make it possible to continuously carry out rock wool production operation, by providing a perforable blocking mud in the sidewall of the lowermost part in a furnace on the opposite side of the outflow port of the melt with respect to the center of a smelting furnace and perforating the mud at an optional time to take out the stored molten iron. CONSTITUTION:Blast furnace slag is charged through a charging inlet 4 into the body of an electric furnace 1 and a preheated component adjusting material is then charged from a charging pipe 8 to adjust a raw material melt 17. The furnace body is tilted by hydraulic cylinders 15 and pistons 16 to continuously feed the raw material melt 17 through an outflow port 9 to a fiber machine 10 and produce the aimed rock wool. In the process, iron and iron oxide in the slag are reduced into molten iron 18, which is gradually stored in the lower- most part of the furnace 1 to reach the height of the outflow port 9. Therefore a perforable blocking mud perforable by a perforating machine 19 is provided in the sidewall of the lower- most part of the furance 1 on the opposite side to the outflow port 9 to perforate the mud by the perforating machine 19 for each given amount of the molten slag. The furnace body 1 is tilted to take out the stored molten iron 18. Thereby the operation can be subsequently transferred to fiber making operation without adversely affecting the continuous fiber making operation.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention involves charging molten slag into a melting furnace, adding and mixing a composition adjusting material to the molten slag, and heating and maintaining the molten slag at a constant temperature. The present invention relates to a method for extracting hot metal from inside the furnace in the operation of a melting furnace that produces rock wool by discharging the melt in small quantities.

[Conventional technology]

High-temperature molten slag, which is produced in large quantities from blast furnaces in steel mills, is quenched with water and processed into wooden frame slag, which is used as blast furnace cement, cement mixture, and 1f! ! It is used as a board improvement material, concrete aggregate, etc. In addition, this slag is discharged onto a vast site, cooled, and processed into crushed slag (slow-cooled slag), which is used as a raw material for rock wool in addition to roadbed materials, aggregates, and landfill materials.

Rock wool is manufactured by adding component adjustment materials to crushed slag stone as necessary, remelting it in a melting furnace such as an electric furnace or cupola, and feeding the melted material to a cotton mill, which uses centrifugal force and/or pressure. A method of forming fibers using fluid pressure such as air or steam has been adopted. This conventional method uses crushed slag stone, which is convenient for transporting and storing raw materials, and it is also easy to adjust the chemical composition of rock wool raw materials, but the enormous amount of heat taken out of the blast furnace can be released and used when cooling. As a result, they are being discarded. Therefore, from the viewpoint of energy saving, a method is attracting attention in which the high-temperature molten slab from the blast furnace is directly charged into the electric furnace, and after the composition and temperature are adjusted, it is supplied to the cotton mill. Publication No., Japanese Patent Application Publication No. 5
It is described in JP-A-1-84929, JP-A-59-131534, etc.

In the former method of using slag crushed stone using a cupola, etc., it involves a remelting process, so it is usually a one-batch method, and even if the iron content in the blast furnace slab accumulates at the bottom of the furnace, it is only one batch, and the quantity is If the amount of slag is small and the discharge port is located at the lower end, a method is used in which the slag containing iron is separately discharged and removed at the beginning. In these processes, since there is no reducing action in the furnace, there is no action of reducing the iron oxide in the slag to iron, so the removal of iron content has not been a serious technical problem.

In the latter method, in which the molten slag is placed in an electric furnace or the like, and the components and heating temperature are adjusted to produce Low 2 Coul, not only the iron content in the slab but also the components contained as iron oxide are removed.
Under the reducing action of the electric furnace's carbon electrodes, etc., the iron becomes molten iron and is stored at the bottom. Moreover, in this process, the blast furnace slabs are received batchwise, but the molten material in the furnace flows out continuously, so the iron content in the slabs and the iron content reduced by iron oxide are
If it flows out with the effluent, it will damage the quality of the fiber. If the molten metal is discharged not from the bottom of the furnace, but from the discharge port above, the molten metal will gradually accumulate at the bottom of the furnace. Japanese Patent Publication No. 51-887
As described in Japanese Patent No. 28, in the method of tilting the melting furnace and discharging from the top into the tundish, the iron accumulated at the bottom of the furnace is removed by not discharging the furnace to the end. Moreover, in Japanese Patent Publication No. 53-37929, on the contrary, heating is performed by induction heating using this stored iron bath or by blowing an additive through the metal bath. In such a case,
Naturally, there is no description of how to extract the hot metal.

[Problem that the invention seeks to solve]

This is not a method in which molten slag is charged into an electric furnace, a composition adjusting material such as silica stone is added, and the heating temperature is adjusted, and then the furnace is tilted and discharged from the top, nor is it discharged from the bottom of the furnace. In this method, the molten slab is intermittently supplied by flowing out a substantially constant amount per hour from the outlet slightly above it and directly supplying it to the cotton mill without going through a separate relay furnace or tumble pusher. When the outflow is carried out continuously, the iron content in the slag and the hot metal in which iron oxide has been reduced in the electric furnace gradually accumulate at the lowest end of the furnace. When this gradually accumulates and reaches the height of the outlet, it flows out together with the raw material melt, causing serious problems in cotton manufacturing.The present invention was made to solve this problem.

[Means for solving problems]

In the present invention, a molten slab is charged into a melting furnace, the composition is adjusted, and the furnace is tilted while being heated and maintained within a constant temperature range, so that a substantially constant amount of the molten slab is removed from a discharge port slightly above the bottom of the furnace. In the operation of a furnace that produces rho and fural by flowing out, a hole can be made with a hole-opening machine on the side wall at the bottom of the furnace on the opposite side of the outflow port from the center of the melting furnace, and it is normally closed with a mud. A tap hole is provided that is closed with a tap hole, and a hole is opened with a hole puncher every time a certain amount of molten slag is processed. This is a method for extracting hot metal from a rock wool raw material melt.

Needless to say, this method cannot be applied to a method in which the molten raw material is constantly extracted from the bottom of the furnace, since the molten metal will also flow out from time to time. In addition, in contrast to the method of using tilting to flow the molten metal from the upper end into the tump push or relay furnace, it is sufficient to flow the molten metal from the north end into a container other than the tump push or relay furnace once a certain amount of molten metal has accumulated. Therefore, this is also not applicable.

The uninvented method is to tilt the melting furnace and let the melt flow out in a substantially constant amount from an outlet slightly above the bottom of the furnace (preferably a position 30 to 40% from the bottom of the liquid depth). This is an effective method for In this case, the hot metal in the blast furnace slag and the hot metal produced by reducing iron oxide in the electric furnace accumulate at the bottom of the furnace as the throughput increases. It is clear that high-quality rock wool cannot be produced if this is poured into a cotton mill along with the melt.

In the present invention, a tilting device is used to flow out a fixed amount of the melt, and a hole can be drilled with a hole puncher at the bottom of the furnace on the opposite side to the melt outlet and the center of the furnace. The tap hole is closed with a plug hole, and the hole is opened with a hole puncher every time a certain amount of molten slab is processed. This is to remove the hot metal that has accumulated at the bottom.

Next, referring to the drawings, FIG. 0 is a longitudinal sectional view of an electric furnace suitable for carrying out the method of the present invention.

1 is the electric furnace main body, 2 is the electrode, 3 is the stirring gas introduction pipe, 4
5 is a blast furnace slag charging port, 5 is a charging device thereof, 6 is a stopper, and 7 is a steel car for transporting blast furnace slag. Reference numeral 8 denotes a charging pipe for a component adjusting material such as preheated silica stone. 9 is an outlet for the rock wool raw material melt, and 10 is a cotton making machine. 11 is a curved smooth surface attached to the lower part of the electric furnace; 12 is a guide roller that rotates in contact with the smooth surface 11; 13 is a base; 14 is a load cell that supports the base 13 at four locations; Keep the overall weight constant at 4. 15 is a fluid cylinder that tilts the electric furnace;
16 is its piston. 17 is the internal raw material melt;
18 is hot metal stored at the bottom. Reference numeral 19 is a hole-opening machine used in the present invention, and the hole 20 of the electric furnace main body l, which is normally blocked with blockage mud, is opened to the time when hot metal 18 is stored in the furnace based on the amount of blast furnace slag processed. The molten pig iron 18 is discharged by tilting the furnace to the left. When all of the stored hot metal 18 is discharged and the effluent turns into molten slag, mud is forced into the opening 20 using a plugging machine such as a mud gun to close it. Of course, in actual operation, it is most preferable to tilt the iron slightly to the left and collect the molten metal in the left corner before drilling the hole.

[Effect]

Instead of pouring out from the upper end of the furnace, the hot metal settles to the bottom of the molten raw material and is extracted from the bottom, so the separation is clear and wasteful molten raw material can be discharged together with the molten metal. No, the raw material is always discharged from the outlet slightly above the bottom of the furnace, so there is no chance of molten metal getting mixed into the raw material despite the tilting method. In addition, since the entire furnace is tilted, only the hot metal can be discharged more efficiently than when holes are opened at the bottom of the furnace, and the tilting device for discharging raw materials can be used in the opposite direction. This made it possible to directly supply cotton from the electric furnace to the cotton mill without going through any relay furnaces, such as those used to separate molten iron.

[Example] A portion of blast furnace slag 1001 was charged into an electric furnace, and preheated silica stone was charged and stirred. TL electric furnace heating, standard temperature 1
Start tilting the furnace from within the range of 470 ± 20°C, and pour out the raw material melt at a substantially constant rate per hour from the outlet in the range of 30 to 40% below the depth of the liquid from the bottom of the furnace. It was supplied to a cotton mill to produce rock wool. When the charging amount reached 75 parts by weight, the furnace was substantially uprighted, 25-1 part of blast furnace slag transported by steel weight from the blast furnace was charged, the preheated silica stone was additionally stirred, and the furnace was heated again. Tilting was started and this was repeated.

At the stage of processing 500 tons of blast furnace slag, a hole is made with a hole puncher at the bottom of the furnace on the opposite side of the outlet from the center of the furnace.
The furnace was tilted backward in this direction and the stored hot metal was extracted.

〔effect〕

As explained above, according to the method of the present invention, since the molten slag whose composition has been adjusted is not discharged from the uppermost end of the furnace, there is an advantage that there is no need for a relay furnace such as a tum pusher in the middle. In addition, in the method of discharging from the lowest part of the furnace,
The hot metal in the slag and the hot metal produced by quintupling iron oxide would flow out together with the slag, causing a serious hindrance to the cotton-making operation, but this does not happen. As described above, this method has advantages over other conventional methods, but the hot metal does not have an outlet, and during the processing of a large amount of molten slag, it accumulates at the bottom of the furnace and eventually rises to the height of the discharge port. When using the method of the present invention, the tilting device of the furnace body is used in the opposite direction, and a tap hole is opened in the side wall of the furnace bottom every time a certain amount of slag is processed to extract hot metal. This has the great effect of allowing the continuous cotton-making operation to be carried out with almost no adverse effect on the continuous cotton-making operation. In addition, hot metal continuously settles to the bottom of the furnace during cotton milling, and in this state, the furnace body is tilted in the opposite direction to the cotton milling process and extracted, so the separation of the hot metal and raw materials is clear, and only the hot metal is removed. It is not necessary to discharge a large amount of raw material melt. Furthermore, since the raw material discharge port is located sufficiently higher than the bottom of the furnace, it is possible to leave the hot metal until it has accumulated to a certain extent, reducing the possibility of interrupting the continuous cotton milling operation. Because I will take advantage of it.

A separate drive device for discharging hot metal is not required. By establishing such a method for extracting hot metal, the present invention can directly supply raw materials from a steel car to a cotton mill via only an electric furnace. This made possible an extremely simple system, and its industrial effects were significant.

[Brief explanation of drawings]

The figure is a longitudinal sectional view of an electric furnace suitable for carrying out the method of the present invention. ■... Electric furnace body (melting furnace) 9... Outflow 1 io... Cotton mill 18... Hot metal 19... Hole punch 20... Hole opening (tapping port) Patent Applicant: Nippon Steel Chemical Co., Ltd.Same applicant: Nippon Steel Corporation, Procedure No. 7 j'
691 No. 2, Title of the invention: Method for extracting hot metal from melted rock wool raw material 3, Person making the amendment 4, Agent 5, Date of amendment order Voluntary 6, Number of parts increased by the amendment 11 None 7, Amendment Supplement to the subject matter ii: Contents 1) Specification: The "Claims" of: shall be corrected as shown in the attached sheet. 2) Delete "tilting the furnace body in the direction opposite to the outflow side to the cotton milling machine" from lines 4 to 5 on page 6 of the specification. 3) The following sentence 1 between page 6, line 7 and line 8 of the specification:
Add π. To remove the hot metal after drilling, if the raw material outlet to the cotton machine or the bottom of the furnace is sufficiently high enough that enough hot metal can be stored, the melting furnace should be placed in an upright position or on the side of the cotton machine or the opposite side. If it is possible to open the tap hole even in the inclined state of By tilting in the opposite direction to the side, hot metal can be extracted properly. 4) Delete [Tilt the furnace body in the direction opposite to the outflow side to the cotton milling machine] from line 10 to line 11 of page 7 of page 1 of the specification. 5) Add the following communication between the 12th line and the 13th line on page 7 of the specification δ medium temperature. Note: When it is necessary to remove hot metal before it accumulates at the bottom of the furnace, the loss of raw materials in the furnace is minimized by tilting the furnace body in the direction opposite to the outflow side to the cotton mill and removing the hot metal. It is possible to extract only the hot metal. Claims (1) Charge molten slag into a melting furnace and adjust the composition,
In the operation of a furnace that manufactures rock wool by tilting the furnace while heating and maintaining it within a constant temperature range, the molten material is flowed out one step at a time from an outlet slightly above the bottom of the furnace.
A tap hole is provided on the bottom side wall of the furnace, opposite the outlet from the center of the melting furnace, so that it cannot be opened with a hole puncher and is always closed with a blocking mat. A method for extracting hot metal from a rock wool raw material melt, characterized by extracting hot metal accumulated at the bottom of a hole-opening furnace using a hole-opening machine every time molten slag is processed. Method for extracting hot metal from rock wool raw material melt.

Claims (1)

[Claims] The molten slag is charged into the melting furnace, the composition is adjusted, and the furnace is tilted while heating and maintained within a certain temperature range to allow the molten material to flow out in substantially constant amounts from the outlet slightly above the bottom of the furnace. In the operation of a furnace for manufacturing rock wool, a hole can be drilled with a hole-opening machine on the side wall at the bottom of the furnace on the opposite side of the outlet from the center of the melting furnace, and it is always closed with a plugging mud. A tap hole is provided, and a hole is drilled with a hole punching machine after a certain amount of molten slag is processed.The furnace body is tilted in the opposite direction to the outflow side to the cotton milling machine, and the molten pig iron stored at the bottom of the furnace is extracted. Features: A method for extracting hot metal from melted rock wool raw material.