JPH116686A - Method and apparatus for feeding steelmaking material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and apparatus for feeding a steelmaking material wherein operation process is simplified and heat loss or the like is improved by feeding the steelmaking material quantitatively without interrupting operation of a steelmaking furnace. SOLUTION: This method of feeding a steelmaking material comprises an initial feeding step of temporally feeding scraps 1 from a storage tank 12 to a lower cutting chute 24 within a throat part 13, a first pushing step of advancing a lower pusher 42 within a range smaller than a full stroke in order to push the scraps 1' in the lower cutting chute 24 into a furnace body 14, a restoration step of retracting the lower pusher 42 from inside the throat part 13 and a second pushing step of advancing the lower pusher 42 by the full stroke in order to push the scraps 1' remaining in the lower cutting chute 24 into the furnace main body 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for supplying a steelmaking material to a steelmaking furnace for melting a steelmaking material such as scrap.

[0002]

2. Description of the Related Art Generally, an arc furnace for steelmaking is known as a steelmaking furnace for melting scrap (steel raw material) such as waste materials of automobile parts and empty cans with high heat to produce steel. FIG. 9 is a cross-sectional view of a main part of a conventional closed-type steelmaking arc furnace, wherein reference numeral 2 denotes a furnace body, and reference numeral 3 denotes a charging bucket as a steelmaking material supply device.

[0003] The furnace body 2 is a furnace equipped with a furnace for melting the scrap 1 by using an arc generated by an electrode (not shown) as a heat source. The charging bucket 3 is a container for transporting the scrap 1, and is suspended from a movable overhead crane (not shown). The bottom of the loading bucket 3 is a bottom cover 3a which can be freely opened and closed.

In a conventional method for supplying a steelmaking material, a predetermined amount of scrap 1 is first charged into a charging bucket 3 in a scrap yard (not shown). Subsequently, the overhead crane is driven to move the charging bucket 3 to just above the furnace body 2 in a state where the operation is stopped. Here, after the furnace lid 2a of the furnace body 2 is slid to open the opening 2b, the bottom cover 3a of the charging bucket 3 is opened and the scrap 1 is dropped into the furnace body 2. Thereby, the scrap 1 is heated by the arc discharge, and the molten steel 4 is stored at the bottom of the furnace body 2.

[0005]

However, in the conventional steelmaking material supply method and the conventional steelmaking furnace, the operation of the furnace is interrupted, the furnace lid 2a is opened, and a large amount of scrap is supplied to the furnace body 2 at one time. . For this reason, the operation process of the arc furnace becomes complicated, and there is a disadvantage that the steelmaking material cannot be supplied quantitatively.

Further, since the furnace lid 2a is opened each time the scrap 1 is charged, the heat loss increases and the power supply is intermittent. For this reason, power efficiency deteriorates, the power consumption increases, and the voltage fluctuation rate (flicker) increases.

Accordingly, the present invention has been made in view of such circumstances, and the steelmaking material is supplied quantitatively without interrupting the operation of the steelmaking furnace, thereby simplifying the operation process and reducing heat loss and the like. An object of the present invention is to provide a method of supplying a steelmaking material and a supply device of the steelmaking material that can be improved.

[0008]

In order to solve the above-mentioned problems, according to the first aspect of the present invention, when the steelmaking material of the storage tank is supplied into the furnace body through a supply passage by an extrudable portion that can move forward and backward. An initial supply step of supplying the steelmaking material from a storage tank to a retaining portion in a supply passage; and a first extrusion in which the extruding portion is advanced by less than a full stroke to extrude the steelmaking material in the retaining portion into the furnace body. Process and
A return step of retreating the extruding section from the supply passage, and a second extruding step of pushing the extruding section forward with a full stroke and extruding the steelmaking material remaining in the retaining section into the furnace body. Features.

[0009] In the first extrusion step, the lower skirt portion of the steelmaking material deposited in the stagnant portion in a triangular cross section is extruded into the furnace body, and the top portion collapses. In the return step, the extruded portion escapes from the steelmaking material, and the steelmaking material is deposited at a certain height. Therefore, in the second extrusion step, the steel making material is quantitatively extruded into the furnace body by the movement of the extrusion section.

According to a second aspect of the present invention, in the first aspect of the invention, in the returning step, the extruding section is moved at a speed higher than the moving speed in the first extruding step and the second extruding step. It is characterized by being moved.
The steelmaking material is continuously supplied to the furnace body by performing the return process at a high speed.

According to a third aspect of the present invention, there is provided an apparatus for supplying a steelmaking material, comprising: a storage tank for storing the steelmaking material; a supply passage for supplying the steelmaking material from the storage tank to a furnace; It is characterized by comprising an extruding portion which can be advanced and retracted from the supply passage to the furnace body, and control means for causing the extruding portion to move alternately in a range smaller than the full stroke and in the full stroke.

In the present invention, the steelmaking material is supplied from the preheating tank into the furnace through the supply passage, and is melted by the high heat in the furnace to produce steel. During this operation, under the control of the control means, a first extrusion step in which the extruding section is advanced in a range smaller than the full stroke to extrude the steelmaking material into the furnace body, and the extruding section is advanced by the full stroke and remains. The second extrusion step of extruding the steelmaking material into the furnace body is performed alternately.

In the first extrusion step, the lower skirt portion of the steelmaking material deposited in the stagnant portion in a triangular cross section is extruded into the furnace body, and at the same time, the top portion collapses and the steelmaking material has a certain height. Deposits. Therefore, in the second extrusion step, the steel making material is quantitatively extruded into the furnace body by the movement of the extrusion section.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a method for supplying a steelmaking material and an apparatus for supplying a steelmaking material according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a sectional view of a main part of a closed-type steelmaking arc furnace according to the present invention, in which reference numeral 12 denotes a preheating tank (storage tank), 13 denotes a throat section (supply passage), and 14 denotes a furnace body. It is. Among these, the supply device of the steelmaking material is schematically constituted by a preheating tank 12 and a throat section 13.

The preheating tank 12 is a hollow shaft-shaped container having an opening at its upper end and serving as a charging port. The preheating tank 12 is, for example, scrap 1 or HBI, which is reduced iron, charged into the furnace body 14.
(Hot briquet iron) or a mixture of scrap and HBI at an appropriate ratio.

Inside the upper part of the preheating tank 12, movable shelves 21, 21 which can be freely opened and closed are mounted.
1 is normally closed to seal the preheating tank 12. An exhaust pipe 2 for discharging exhaust gas is provided in the preheating tank 12.
2, 22 are connected. The bottom portion of the preheating tank 12 is formed gently down to the throat portion 13 side, and forms a scrap cutting chute 23 which is a dropping path for guiding the scrap 1. On the bottom side of the preheating tank 12, an upper pushing means 3 for pushing the scrap 1 to the throat section 13 is provided.
1 is provided.

The upper pushing means 31 includes a rod-shaped upper pusher 32 that can move forward and backward along the inclination of the upper cutout chute 23, an upper pusher storage chamber 33 in which the upper pusher 32 at the standby position is stored, and an upper pusher 32. And an upper hydraulic cylinder 34 to be driven.

The upper end of the throat section 13 has a preheating tank 12
Is connected to the bottom side surface of the
Is connected to a scrap insertion port 15 provided at the top of the scrap 1 to form a supply passage for the scrap 1. Further, the throat section 13 removes high-temperature exhaust gas generated in the furnace body 14 from the preheating tank 1.
The scrap 1 is also preheated by the exhaust gas, leading to a reduction in power consumption.

In the lower portion inside the throat portion 13, a preheating tank 1 is provided.
A lower cut-out chute (retaining portion) 24 is formed to be a horizontal surface for temporarily retaining the scrap 1 extruded from 2. A lower extruding means 41 for extruding the scrap 1 on the lower cutout chute 24 is provided.

The lower pusher 41 has a rod-shaped lower pusher (extrusion section) 42 that can move horizontally along the lower cutout chute 24 and a lower pusher 42 at a standby position.
And a lower hydraulic cylinder 44 for driving the lower pusher 42.

The entire stroke of the lower pusher 42 is set so as to reach the front end of the lower cutout chute 24 when the lower pusher 42 advances to the foremost position. This is to enable the scrap 1 remaining in the lower cutout chute 24 to be extruded into the furnace body 14 without being left.

Further, as shown in FIG. 2, this steelmaking material supply apparatus detects a drive control unit (control means) 51 for controlling the operation of the upper pushing means 31 and a moving amount and a moving speed of the upper pusher 32. Moving amount detecting section 52, and a drive control section (control means) 53 for controlling the operation of the lower pushing means 41.
And a movement detector 54 for detecting the amount and speed of movement of the lower pusher 42.

Each of the drive control units 51 and 53 is connected to each signal line so that a signal from the operation monitoring unit 55 is input, and the movement amount detection units 52 and 54 are input signals to the operation monitoring unit 55. Signal lines are connected as described above.

Next, a method for supplying a steelmaking material according to the present invention will be described. The method for supplying the steelmaking material includes an initial supply step, a first extrusion step, a return step, and a second extrusion step.

First, in the initial supply step, as shown in FIG. 1, the loading bucket 3 into which the scrap 1 has been loaded is lowered to enter through the loading port 12a of the preheating tank 12, and the bucket bottom cover 3a is opened. . Thereby, the scrap 1 falls and is stored on the movable shelves 21 and 21.

Next, the movable shelves 21 and 21 are opened, and the scrap 1 is charged into the preheating tank 12. Thus, the inside of the preheating tank 12 is filled with the scrap 1 as shown in FIG.
In this state, the scrap 1 remains in the preheating tank 12 and is not supplied to the throat section 13.

Then, as shown in FIG. 4, the upper pusher 32 is advanced into the preheating tank 12 by the upper hydraulic cylinder 34 (see FIG. 8). Thus, the scrap 1 in the preheating tank 12 is pushed out from the upper cutout chute 23, and a part of the scrap 1 falls into the lower cutout chute 24. The extruded scrap 1 'is deposited on the lower cutout chute 24 in a triangular cross section.

The amount of scrap 1 cut from the upper cut chute 23 is proportional to the amount of movement of the upper pusher 32. Therefore, the moving amount of the upper pusher 32 is appropriately set in advance corresponding to the amount of the scrap 1 that can be melted at one time in the furnace body 14.

In the first extruding step, as shown in FIG. 5, the lower hydraulic cylinder 44 moves the lower pusher 42 to a range smaller than the entire stroke, for example, 0.30 L to 0. It is advanced by a moving distance (intermediate stroke) of 85L (see FIG. 8).

The lower pusher 42 extrudes the scrap 1 ′ little by little from the tip of the triangle 1, that is, the lower skirt. In addition, the lower pusher 42 penetrates into the lower part of the mountain of the scrap 1 ′ so that the top portion of the scrap 1 ′ collapses on the lower pusher 42.

In the return step, as shown in FIG. 6, the lower pusher 42 is retracted to the standby position of the lower pusher storage chamber 43 (see FIG. 8). At this time, when the lower pusher 42 comes out of the scrap 1 "from the scrap 1" which has collapsed, the scrap 1 "falls on the lower cutout chute 24 to form a mountain whose upper portion is substantially flat.

In this return step, the lower pusher 4
2 is controlled to retreat at a higher speed than the moving speed of the lower pusher 42 in the first extrusion process and the second extrusion process. Although the supply of the scrap 1 is not performed in the return step, the interruption of the supply of the scrap 1 can be minimized by shortening the time required for the return step.

In the second extrusion step, as shown in FIG.
The lower pusher 42 is advanced by the lower hydraulic cylinder 44 with a full stroke (see FIG. 8). Since the front end of the lower pusher 42 is set so as to reach the front end of the lower cutout chute 24 when the lower pusher 42 moves in the entire stroke, all the scrap 1 ″ remaining in the lower cutout chute 24 is removed from the furnace body 14 ( Extruded to Fig. 1).

[0034] Since the upper portion of the scrap 1 "is deposited as a flat mountain, the scrap 1" is quantitatively dropped into the furnace body 14 with the movement of the lower pusher 42. The lower pusher 42 is moved in the return process. Since the speed is set lower than the speed, the scrap 1 is cut out little by little and supplied to the furnace body 14.

Thereafter, the lower pusher 42 is returned to the standby position of the lower pusher storage chamber 43. This return operation is also performed at a high speed, and interruption of the supply of the scrap 1 can be minimized.

One cycle consisting of the initial supply step, the first extrusion step, the return step, and the second extrusion step is sequentially repeated. As described above, the operation process can be simplified, and the scrap 1 is continuously and quantitatively reduced little by little.
4 will be supplied.

Further, since the furnace body 14 is not opened, the heat loss is small and the power needs to be continuously supplied, so that the power efficiency is improved, the power consumption is reduced, and the voltage fluctuation rate (flicker) is suppressed. Can be.

In FIG. 2, the upper pusher 32
The moving amount and moving speed of the lower pusher 42 and the furnace body 1
In accordance with the scrap dissolution amount of No. 4, it can be appropriately changed by input from the operation monitoring unit 55 shown in FIG.

The operation monitor 55 is supplied with signals relating to the moving speed and the amount of movement of the upper and lower pushers 32, 42, and the operator can monitor the operation status of the arc furnace by displaying the operation monitor 55. it can.

In this embodiment, the case where two extruding means 31 and 41 are provided has been described. However, it may be constituted by only the lower extruding means or may be constituted by three or more extruding means. . Further, in this embodiment, the upper and lower pushers 32, 42 are driven by the hydraulic cylinders 34, 44, but other driving means, for example, an electric type may be used.

[0041]

As described above, according to the first aspect of the present invention, after the steelmaking material is formed into a substantially flat mountain in the first extrusion step and the return step, the steelmaking material is formed in the third extrusion step. Is extruded into the furnace body, so that the steelmaking material can be continuously and quantitatively supplied to the furnace body in small amounts in a simple operation process. Further, since it is not necessary to open the furnace, heat loss is reduced, power efficiency is improved, power consumption is reduced, and flicker can be suppressed.

According to the second aspect of the present invention, the time required for the return step can be shortened, so that the steelmaking material can be continuously supplied to the furnace body.

According to the third aspect of the present invention, the steelmaking material is made into a substantially flat mountain by moving the extruding portion in a range smaller than the entire stroke, and then the steelmaking material is transferred to the furnace body by moving the extruding portion in the entire stroke. Since it is extruded, the steelmaking material can be continuously and quantitatively supplied to the furnace body little by little.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a steelmaking material supply apparatus according to the present invention.

FIG. 2 is a block diagram showing a configuration of a steelmaking material supply device according to the present invention.

FIG. 3 is a sectional view (1/5) showing a method for supplying a steelmaking material according to the present invention.

FIG. 4 is a sectional view (2/5) showing a method for supplying a steelmaking material according to the present invention.

FIG. 5 is a sectional view (3/5) showing a method for supplying a steelmaking material of the present invention.

FIG. 6 is a sectional view (4/5) showing a method for supplying a steelmaking material according to the present invention.

FIG. 7 is a sectional view (5/5) showing a method for supplying a steelmaking material according to the present invention.

FIG. 8 is a diagram illustrating the operation of each pusher in the method for supplying a steelmaking material according to the present invention.

FIG. 9 is a view showing a conventional method of supplying a steelmaking material.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Scrap 2 Furnace body 3 Charging bucket 12 Preheating tank 13 Throat part 14 Furnace body 15 Scrap inlet 23 Upper cutout chute 24 Lower cutout chute 31 Upper pushing means 32 Upper pusher 33 Upper pusher storage chamber 34 Upper hydraulic cylinder 41 Lower pushing means 42 Lower pusher 43 Lower pusher storage chamber 44 Lower hydraulic cylinder 51,53 Drive controller 53,54 Movement detector 55 Operation monitor

Claims (3)

[Claims] 1. An initial supply step of supplying the steelmaking material in a storage tank to a furnace body through a supply passage through a supply passage by an extrudable part that is capable of moving forward and backward, wherein the steelmaking material is supplied from the storage tank to a storage section in a supply passage. A first extrusion step of advancing the extruding section within a range smaller than the entire stroke to extrude the steelmaking material of the stagnation section into the furnace body, a return step of retracting the extruding section from within the supply passage, and A second extrusion step of moving the steelmaking material remaining in the stagnation section forward with the entire stroke and extruding the steelmaking material into the furnace body. 2. The method according to claim 1, wherein in the returning step, the extruding section is moved at a speed higher than a moving speed in the first extruding step and the second extruding step.
Supply method of the steel making material described. 3. A storage tank for storing the steelmaking material, a supply passage for supplying the steelmaking material from the storage tank to the furnace body, and an extrudable portion that pushes out the steelmaking material from the supply passage to the furnace body. And a control means for causing the extruder to alternately move the extruder in a range smaller than the full stroke and in the full stroke.