JPH01198414A - Apparatus and method for charging raw material in smelting reduction furnace - Google Patents

Abstract

PURPOSE:To automatically exfoliate and remove slag and metal stuck on a chute and to stably execute charging of raw material by assembling mechanism for cleaning inner face of the chute in a metal smelting reduction furnace having the chute for charging the raw material at the side face. CONSTITUTION:At the opening part 9 of upper side wall in a converter type refining furnace 1 charging molten metal 4 and molten slag 5, the chute 10 for charging the raw material is inserted and the raw material 19 in a raw material tank 15 is supplied into the chute 10 through a raw material supplying pipe 16 and by using inclination of the chute 10, the raw material 19 is charged into the refining furnace 1. In this case, the inclination of the chute 10 is decided so as to drop down the raw material at the outside of 1/3 of the radius R of the furnace from the center of the refining furnace 1. Further, the chute 10 is water-cooled and semi-round trough-type, cylindrical or square tubular scraper 29 having tapered-shape at the inner face is fitted. The chute 10 is not eroded by water cooling and the stuck material 30 of slag and stuck on the inner face at the tip part 32 is removed and cleaned by advancing/retreating an acute tip 31 of the scraper 29, and the raw material can be stably supplied without any clogging in the chute.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus and method for charging raw materials such as powdered or lumpy iron ore or carbonaceous material into a smelting reduction furnace.

[Conventional technology]

In order to reduce iron ore to produce hot metal, methods such as using a blast furnace and melting iron ore raw material reduced in a shaft furnace in an electric furnace have been adopted. However, the blast furnace method requires large-scale equipment. Also,,
Since sintered ore is used as the iron source and coke produced by carbonizing highly caking coal, ancillary equipment such as coke oven equipment and sintering equipment is required. Therefore, not only is there a huge equipment cost, but
This method has the drawback of requiring a large amount of energy and labor, leading to a rise in processing costs. On the other hand, the method of reducing iron ore using a shaft furnace requires pre-treatment to pelletize the iron ore, and has the disadvantage that it consumes a large amount of expensive natural gas as a reducing agent and heat source.

As an alternative to such conventional hot metal production techniques, the smelting reduction method is attracting attention. The smelting reduction furnace used in this method was developed for the purpose of producing molten iron alloys using smaller-scale equipment without being restricted by the raw materials used.
There are converters, mixed pig iron furnaces, etc. as disclosed in No.-86794.

In this type of smelting reduction furnace, like conventional metallurgical furnaces for iron making or steel making, lumps of iron ore and carbonaceous materials are fed into the furnace from a charging device placed at the top of the furnace body through an exhaust gas hood and the furnace mouth. etc. are being introduced. However, in a smelting reduction furnace, powdered iron ore or carbonaceous material is mainly charged, and fine powder of 1 ma+ or less is often used because it is desired that the refining reaction proceed rapidly. Therefore, the raw materials that have been introduced are scattered inside the furnace and cannot efficiently reach the slag layer and the molten metal bath.

In addition, the exhaust gas generated inside the smelting reduction furnace is recovered,
Powdered raw materials are advantageous for use in prereduction furnaces, preheating furnaces, exhaust gas boilers, etc., and because they are directly connected to the gas flow,
The exhaust gas hood is hermetically connected to the furnace mouth. Normally, the flow rate of exhaust gas flowing through this exhaust gas hood is high. When raw materials are introduced from a raw material input device opened to such an exhaust gas hood, a large proportion of the raw materials are carried away from the system by being carried away by the flow of exhaust gas.

[Problem to be solved by the invention]

Therefore, in order to increase the consumption efficiency of the input raw materials, a method was implemented in which a raw material input port was opened in the inner wall of the smelting reduction furnace and the raw materials were allowed to fall from the inner wall into the slag layer inside the furnace.

However, when the raw material inlet is opened on the inner wall of the furnace body,
Slag, metal, etc. that are scattered or formed in the furnace adhere to the raw material input port, causing blockage and preventing smooth raw material input. In addition, the parts of the raw material feeding device that come in contact with the raw materials are subject to severe wear, and if the feeding device is equipped with a water cooling mechanism, cooling water may leak from the water cooling mechanism in a short period of time due to partial wear, causing serious accidents. It also becomes.

In order to prevent problems caused by such deposits, it is necessary to always maintain the raw material input section in a clean state. However, since the raw material inlet opens into the furnace, cleaning work becomes troublesome.

Therefore, the present invention incorporates a mechanism that cleans the sheet surface of the raw material input section, thereby automatically peeling off adhered slag, metal, etc., and ensuring that raw materials are always input under stable conditions. The purpose of the present invention is to provide a raw material input device and a raw material input method.

[Means to solve the problem]

In order to achieve the purpose, the raw material input device of the present invention has the following features:
A chute provided in a chute insertion opening drilled in an upper furnace wall of a smelting reduction furnace so as to be able to move forward and backward; a scraper inserted into the sheet and movable in the longitudinal direction; and a scraper provided in a vessel wall of the chute. It is characterized by being equipped with a water cooling mechanism.

Here, a scraper having a semicircular gutter-like, cylindrical, or prismatic cross-section can be used. In addition, in order to relatively move the scraper forward and backward along the longitudinal direction of the chute, a sliding device is attached directly to the chute, or a means is adopted in which the scraper is fixed via a support to a lifting device that moves the chute forward and backward. . Further, as this chute, one having a tapered surface formed at the tip can be used.

In addition, when feeding the raw material into the smelting reduction furnace, the furnace wall of the smelting reduction furnace should be placed so that the falling position of the raw material with respect to the slag layer is outside R/3 from the center of the furnace, where R is the radius inside the furnace. This is done by adjusting the amount of protrusion from the inner surface of the furnace body or the charging angle of a chute provided in a continuous manner.

〔Example〕

Hereinafter, the features of the present invention will be specifically explained using examples with reference to the drawings.

FIG. 1 shows a melting reduction furnace equipped with a raw material charging device of the present invention.

The furnace body 1 of the melting reduction furnace is formed into a converter type, is supported by a trunnion bearing 2, and is tilted by a tilting device 3 during tapping, etc.
tilted by. A molten metal bath 4 and a slag layer 5 are formed inside the furnace body 1, and oxygen or an oxygen-containing gas is blown toward the slag layer 5 from an upper blowing lance 6. The exhaust gas and exhaust heat generated within the furnace are recovered by an exhaust gas hood 8 provided above the furnace lower and transported to a subsequent process.

Conventionally, a device was attached to open a part of the exhaust gas hood 8 and introduce raw materials such as granular iron ore and carbonaceous material therein. On the other hand, in this embodiment, a chute insertion opening 9 is provided in the wall surface of the furnace body 1, and the chute 10 of the raw material charging device is made to face the chute insertion opening 9. This chute insertion opening 9 can be opened by pulling out the cover body 10 when raw materials are not being put in, such as when tapping hot water.
It is blocked by 1. Note that the reference number 11a indicates the lid 1.
This is a switching device that performs opening/closing operations.

10 is placed on the lifting platform 12, and the lifting device 13
Towed by. Thereby, the chute 10 enters or retreats into the chute insertion opening 9.

A raw material inlet pipe 14 is connected in the middle of the chute 10, and a raw material supply pipe 16 extending from a raw material tank 15 is detachably connected thereto. Further, an exhaust gas purge pipe 18 for blowing inert gas, which is equipped with a purge valve 17, is opened in the middle of the raw material supply pipe 16. Further, a cutoff valve 20 is provided in the middle of the raw material supply pipe 16 in order to send out the raw material 19 contained in the raw material tank 15 or to stop the supply. Note that, as shown in the figure, the raw material supply pipe 16 can be divided into two parts, and the telescopic pipe 21 and the attachment/detachment device 22 can be provided between them. In this case, from the raw material tank 15
Since fluctuations in the distance to NO can be absorbed by the expandable tube 21, spilling of raw materials and leakage of exhaust gas can be prevented.

-) 10 is an inner tube 23. as shown in FIG. Outer tube 2
4 and a partition pipe 25. A water supply pipe 26 is opened between the inner pipe 23 and the partition pipe 25, and a drain pipe 27 is opened between the partition pipe 25 and the outer pipe 24. Therefore, the cooling water supplied from the water supply pipe 26 passes through the inside of the container wall while cooling the container wall.
It is discharged from the drain pipe 27. Furthermore, a scraper 29 that is slid in the longitudinal direction of the chute 10 by a sliding device 28 is arranged inside the chute 10 . This scraper 29 is formed into a shape corresponding to the inner surface shape of the inner tube 23.

This chute 10 is made to protrude into the inside of the furnace body 1 from the chute insertion opening 9, and blowing is performed without charging the raw material 19 contained in the raw material tank 15. That is, the raw material 19 is transferred from the raw material tank 15 to the raw material supply pipe 16° and the raw material inlet pipe 14.
．． It is fed into the furnace through a chute 10. At this time, slag and metal particles flying into the furnace tend to adhere to the tip of the chute 10. If such deposits 30 exist, the raw material 19 will not slide smoothly on the surface of the chute 10, and the raw material will not be fed smoothly.

Therefore, the sliding device 28 is driven and the scraper 29 is moved periodically or when an adverse effect due to the deposits 30 is expected.
-) advance in the longitudinal direction of 10; As a result, the tip 31 of the scraper 29 protrudes from the tip 32 of the scraper 10, as shown by the dashed line in FIG.

Therefore, the deposits 30 adhering to the inner surface of the chute 10 from the solid line position to the dashed-dotted line position of the tip portion 31 are scraped off by the scraper 29 and sent into the furnace.

As the material of the scraper 29, a material having heat resistance and wear resistance is used, such as heat resistant steel.

Heat-resistant cast iron, stainless steel, high-strength steel, FCD, ceramic tube or ceramic liner, etc. are used.

Further, as the scraper 29, in addition to the semicircular gutter shape shown in FIG. 2, a cylindrical or rectangular tube shape (not shown) can be used. FIG. 3 shows an example of this.

That is, the cylindrical scraper 33 is arranged inside the chute 10 so as to be movable forward and backward. The cylindrical scraper 33 is provided with an opening 34 having a predetermined length in the axial direction so that the inside thereof is connected to the raw material inlet pipe 14 in either the forward position or the backward position. The raw material 19 cut out from the raw material tank 15 is transferred to the raw material supply pipe 16. Raw material inlet pipe 14. It is sent into the inside of the cylindrical scraper 33 through the opening part 34, and the tip part 3 of the
From 2 onwards, it is put into the furnace.

The cylindrical scraper 33 is in sliding contact with the entire inner surface of the chute 10. Therefore, even if the deposit 30 is attached to the upper inner surface of the chute 10, for example, it is scraped off and returned to the furnace while the cylindrical scraper 33 moves to the position shown by the dashed line.

Furthermore, although not shown in the drawings, when the chute 10 is made into a square shape, it goes without saying that the same effect can be obtained even if a square tubular scraper is employed.

Scraper 29 or cylindrical scraper 33 shot 1
As a method for sliding it with respect to 0, instead of the sliding device 28, the movement when the Shiny) 10 is extracted from the furnace body 1 can be used. FIG. 4 shows an example of this.

As the blowing progresses, the amounts of the molten metal bath 4 and the slag layer 5 increase. Therefore, usually, the furnace body 1 is tilted by the tilting device 3 to tap the hot water or tap the slag.

At this time, from the chute insertion opening 9 of the furnace body 1, -N
o and close the chute insertion opening 9 with the lid 11. This removal of the shi, -) 10 is performed by hoisting the lifting platform 12 up and down with the lifting device 13.

Therefore, a support 35 is erected on a part of the lifting device 13, and a scraper 29 is attached to this support 35. As this scraper 29, either a semicircular gutter shape as shown in FIG. 2, a cylindrical shape or a rectangular tube shape as shown in FIG. 3 can be used. With this configuration, the scraper 29 is relatively inserted into the chute 10 when the shaft 10 is retracted. As a result, the second
As explained with reference to the drawings and FIG. 3, the deposits adhering to the inner surface of the chute 10 are removed by the scraper 29 and returned to the furnace.

Further, it is preferable that the tip of the chute 10 has a tapered surface 36 as shown in FIG. With this tapered surface 36, even if slag or metal adheres to the outer surface of the chute 5-) 10 and the inner surface of the chute insertion opening 9, the taper between the outer surface of the chute 10 and the inner surface of the chute insertion opening 9 is maintained. It can be configured to be easy to pull out depending on the surface. As a result, the work of pulling out the seat 10 from the chute insertion opening 9 becomes easier. As a result, shoot 10
There is no need to ultimately cut off the tip of the cylindrical shell 10 in order to tilt the furnace body 1 because it becomes impossible to pull it out due to deposits.

It is preferable to charge the raw material 190 using this chute 10 in the range from R/3 to the inner wall, where the radius inside the furnace is R, as shown in FIG. This range is less affected by the blowing gas ejected from the top blowing lance 6, and the raw material 19 introduced from the chute 10 falls freely onto the slag layer 5. In addition, since the raw material 19 passes through the relatively gentle slag layer 5, the charging efficiency of the raw material 19 is improved, and the raw material 19 is not blown up by the blowing gas or carried away by the scattering of slag or molten metal.

Further, the raw material 19 falling near the furnace wall also acts as a shield against the high heat in the center, thermally protecting the inner wall of the furnace body 1. As a result, it also helps to extend the life of the furnace body 1.

In addition, in the above example, one sheet for the furnace body 1,
- The case where the holder 10 is attached has been explained. However, the present invention is not limited to this, and for example, the slag layer 5
Of course, a plurality of holes 10 can be provided through the furnace wall so as to uniformly supply the raw material 19 to the furnace wall.

〔Effect of the invention〕

As explained above, in the present invention, a chute insertion opening is provided in the furnace wall of a smelting reduction furnace, and powdered and lumpy iron ore is passed through the chute disposed in the opening.

Raw materials such as carbonaceous materials are put into the furnace. Therefore, the rate at which the input raw materials are carried away by the exhaust gas rising in the furnace is drastically reduced, and the raw materials are efficiently consumed in the smelting reaction. At this time, the slag, metal, etc. adhering to the inner surface of the shinito can be removed by a scraper, so the inner surface of the shinito is kept clean and raw materials can be fed smoothly. Furthermore, the charged raw materials have the effect of blocking the amount of heat dissipated from the high-temperature atmosphere at the center of the furnace, so they also serve to thermally protect the furnace walls.

[Brief explanation of the drawing]

FIG. 1 shows a smelting reduction furnace equipped with a chute according to a first embodiment of the present invention, FIG. 2 shows details of the chute, and FIGS. 3 to 5 are diagrams for explaining other embodiments. It is a diagram. 1: Furnace body 2: Trunnion bearing 3: Tilting device 4: Molten metal bath 5 Nislag layer
6: Top blowing lance 7: Furnace mouth 8:
Exhaust gas hood 9 Nijiate insertion opening 10 Nijiate 11: Lid 11a: Lid opening/closing device 1
2: Elevating platform 13: Elevating device 14: Raw material inlet pipe 15: Raw material tank 16: Raw material supply pipe
17: Purge valve 18: Exhaust gas purge pipe 19
: Raw material 20: Cut-out valve 21: Telescopic pipe 22:
Attachment/detachment device 23: Inner tube 24: Outer tube
25: Partition pipe 26: Water supply pipe 27
: Drain pipe 28: Sliding device 29: Scraper 30: Deposits 31: Scraper tip 32: Chute tip 33: Cylindrical scraper 3
4: Opening 35: Support 36: Taber surface
R: Furnace Radius Patent Applicant: Nippon Steel Co., Ltd. Representative: Mr. Kojiro
Masu (2 others) Figure 1 Figure 2 Figure 3 Figure 19〉;;L30 ,, (j, j Figure 4

Claims (1)

[Scope of Claims] 1. A chute provided in a chute insertion opening drilled in an upper furnace wall of a smelting reduction furnace so as to be freely advanced and retractable; a scraper inserted into the chute and movable in the longitudinal direction; A raw material input device for a smelting reduction furnace, characterized by comprising a water cooling mechanism provided on a wall of a chute. 2. A raw material charging device for a melting reduction furnace, wherein the scraper according to claim 1 has a semicircular gutter-like cross section. 3. A raw material charging device for a melting reduction furnace, wherein the scraper according to claim 1 has a cylindrical or prismatic cross section. 4. A raw material charging device for a melting reduction furnace, comprising a sliding device for moving the scraper according to claim 1 along the longitudinal direction of a chute. 5. In order for the scraper to relatively enter the inside of the chute when the chute is retracted as described in claim 1,
A raw material feeding device for a smelting-reduction furnace, characterized in that a scraper is fixed via a support to an elevating device that advances and retreats a chute. 6. A raw material charging device for a melting and reduction furnace, wherein the chute according to claim 1 has a tip portion having a tapered surface. 7. The falling position of the raw material with respect to the slag layer is
A smelting reduction characterized by adjusting the amount of protrusion from the inner surface of the furnace body of a chute provided through the furnace wall of the smelting reduction furnace so that it is outside R/3 from the center of the furnace. How to feed raw materials into the furnace.