JP2921381B2 - Electric furnace with rotating pre-tropics - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric furnace provided with a rotating pre-tropical zone for a material to be melted.

[0002]

2. Description of the Related Art Preheating of an object to be melted in an electric furnace is not easy.
Heretofore, for example, an apparatus as shown in FIG. 7 has been used. The lysate 8 such as steel scrap 7 is conveyed to the preheating zone 20 by instrumentation necessity conveyor 21, dissolved in an electric furnace main assembly 1 is preheated with hot exhaust gas generated from an electric furnace body 1 during refining . The material 8 to be melted, such as preheated steel chips, is
1 discharges from the pre-tropical zone 20 to the electric furnace main body 1.
In FIG. 7, reference numeral 1a denotes an exhaust gas outlet, and 4 denotes an exhaust gas suction port.
I'm a quote fan.

[0003]

In the apparatus shown in FIG. 7, the conveyed material 8 is conveyed into the pre-tropical zone 20 by the conveyor 21, so that the clogging of the dissolved object 8 in the pre-tropical zone 20 is prevented. 8 had to be reduced. Follow
The ceiling wall of the pre-tropical zone 20 and the surface of the material 8
There are gaps where high-temperature exhaust gas passes
Thus, the efficiency of heat exchange with the material to be melted 8 is as low as about 50%,
A sufficient preheating effect of the material to be melted 8 was not obtained. The present invention
Has been made in view of these circumstances, and its purpose is to
Efficient removal of substances to be dissolved by exhaust gas generated from the electric furnace body
An object of the present invention is to provide an electric furnace which can be preheated.

[0004]

Means and Action for Solving the Problems Solving the above issues
The electric arc furnace according to the present invention for performing
Between the exhaust gas outlet of exhaust gas and the fan for exhaust gas suction
An electric furnace having a pre-tropical zone for pre-heating an object;
A discharge band, which is open to an exhaust gas discharge port of the electric furnace body,
Rotating cylinder that is rotatable about the center by joining this discharge zone
And this rotary cylinder, and the upstream side in the flow direction of the material to be melted
And a charging zone having a charging port for the material to be melted therein.
The rolling cylinder is on the horizontal surface with the inlet side of the melt
It is inclined, and the rotating cylinder rotates,
It is characterized by being filled with a melt. Soshi
In the discharge zone, the material to be melted is discharged into the electric furnace body.
Independent discharge mechanism such as conveyor and pusher for
Is preferably provided.

Hereinafter, the present invention will be described with reference to FIGS. 1 and 2 corresponding to an embodiment. Flue gas exhaust outlet 1a of the electric furnace body 1
An electric furnace having a pre-tropical zone A for preheating the material to be melted 8 between the gas and the exhaust gas suction fan 4 , the pre-tropical zone A is inclined with respect to a horizontal plane with the charging port 6 side of the material to be melted 8 as an upper portion. and, and a rotatable rotary cylinder 3 to the center as an axis, and joined to the electric furnace body 1 one, and a discharge zone 2 for joining the other to the rotary cylinder 3, the dissolution on the upstream side of the flow of the melt 8 It has a charging port 6 for the object 8 and a charging band 5 in contact with the rotary cylinder 3.

The material to be melted 8 charged by the charging conveyor 9 from the charging inlet 6 enters the rotary cylinder 3 by its own weight. The rotary cylinder 3 rotates around the center as an axis. The to-be-dissolved substance 8 is filled in the rotary cylinder 3 while moving upward in the rotary cylinder 3 while being lifted upward with its rotation. FIG. 2 shows this filling situation, and the filling is performed by the mechanism described below. When the rotating cylinder 3 rotates, the rotating cylinder 3 and the material to be melted 8 are rotated.
Alternatively, the material to be melted 8 is lifted upward due to friction between the materials to be melted 8. Dissolved material 8 lifted upward
Because the rotary cylinder 3 is inclined, it falls from the initial position to the discharge zone 2 side. If there is a space in the place where the melt 8 falls, if there is a space, the melt 8 is carried to the front discharge zone 2 side by repeating this, and drops and deposits on the discharge zone 2. Further, while rotating the rotary cylinder 3,
Is loaded into the rotary cylinder 3, the melted material 8 that has fallen and accumulated in the discharge zone 2 forms a heap, and the melted material 8 discharged from the rotary cylinder 3 is blocked, and The discharge speed becomes slower, and the to-be-dissolved substance 8 fills the rotary cylinder 3.

[0007] the lysate was filled 8 dissolved in an electric furnace main assembly 1, is preheated in the secondary combustion of the flame of the high-temperature exhaust gas and the exhaust gas generated in the smelting, it is discharged into an electric furnace body 1. This discharge method to the electric furnace body 1 includes rotating the rotary cylinder 3,
Alternatively, this is achieved by providing an independent discharge mechanism in the discharge band 2 irrespective of the rotation of the rotary cylinder 3. Independent discharge mechanism
By installing, the filling of the to-be-dissolved substance 8 in the rotating cylinder 3
And discharge of the material 8 to be melted into the electric furnace main body 1 independently.
I can.

By providing spiral grooves or projections in the rotary cylinder 3, the filling efficiency by rotation is improved, and it is also effective to install them.

[0009]

(Embodiment 1) FIG. 1 is a longitudinal sectional view showing one embodiment of the present invention. Preheating body
A is a rotating cylinder 3 rotatably around an axis, one of them in contact with the exhaust gas outlet 1a of the side wall of the electric furnace body 1, a discharge zone 2 which is in contact with the rotating cylinder 3 and the other, of the lysate 8 on the upstream side of the flow it consists has a spout 6 of the lysate, the rotating cylinder 3 in contact SoIritai 5. Furthermore , branch off from charging zone 5
Flue 7 is provided Te, the flue 7 exhaust gas suction fan 4 for sucking the hot waste gas generated from the electric furnace body 1 is eclipsed set <br/>. Rotating cylinder 3 constituting the main body of the preheating zone A is
It is installed at an angle of 10 degrees with respect to the horizontal plane with the inlet 6 side as the upper part. The rotating cylinder 3 has an outer diameter of 3 m and a length of 20 m.
The rotation speed is up to 5 rpm.

The material to be melted 8 charged through the charging port 6 enters the rotary cylinder 3 by its own weight. The rotating cylinder 3 is rotated by a rotating mechanism (not shown). The object 8 to be melted is filled into the rotary cylinder 3 to the ceiling by rotation. Dissolved substance 8 filled
Is efficiently preheated by high-temperature exhaust gas generated by melting and refining in the electric furnace main body 1 and a flame of secondary combustion of the exhaust gas, and is discharged to the electric furnace main body 1. This discharge is achieved by rotating the rotary cylinder 3, and the discharge speed of the melt 8 to the electric furnace main body 1 in this embodiment is controlled to 0 to 5 Ton / min by changing the rotation speed of the rotary cylinder 3. It was possible.

FIG. 3 shows the relationship between the average filling rate of the melt 8 in the rotary cylinder 3 and the rate of temperature rise of the melt 8. Dissolved material 8
Was changed to 100, 95, 90, 85, and 80%, and the temperature of the material to be dissolved 8 was continuously measured. In this case, the rotating cylinder 3 is not rotating in order to keep the average filling rate constant.
The horizontal axis in FIG. 3 shows the average filling rate of the substance 8 in the rotating cylinder 3, and the vertical axis shows the substance filling at a certain time when the average filling rate of the substance 8 is 100%. The figure shows the specific heating rate when the heating rate of 8 is set to 1, and the higher the specific heating rate, the faster the heating, that is, the better the preheating efficiency. According to this figure, the average filling rate of the material to be dissolved 8 is 85 to 80%.
Becomes less, heating rate and the average fill factor as compared with the case of 100% is less than half, also correspondingly be sufficient preheating efficiency can be obtained when the average filling factor of the melt 8 is not less than 90%
It was . In the case of rotation, the preheating efficiency is further improved by making the temperature uniform by the rotation, and the preheating efficiency is further improved.

Accordingly, the present invention provides a method for dissolving the material 8 in the rotary cylinder 3.
Can be 90% or more, and sufficient preheating efficiency can be obtained.

(Embodiment 2) FIG. 4 shows a plate-like conveyor 11 as a discharge mechanism ,
1 shows an embodiment provided in FIG. A plate-like conveyor 11 that is slidable on the bottom surface of the discharge zone 2 in the direction of the discharge port 1a is arranged, and other configurations are the same as those of the first embodiment.

The present embodiment is the same as the first embodiment until the completion of preheating of the material 8 to be melted. The discharge mechanism to the electric furnace main body 1 after the completion of preheating is different. The melt 8 is discharged to the electric furnace main body 1 when the plate-shaped conveyor 11 folds back and forth.

The rotating cylinder 3 is moved by the sliding of the plate-shaped conveyor 11.
Can be discharged to the electric furnace main body 1 without being affected by the rotation of the rotating furnace 3. The rotation of the rotating barrel 3 only needs to control the filling of the material to be melted into the rotating barrel 3, and a stable filling rate can always be obtained. Was.

(Embodiment 3) FIGS. 5A and 5B show an embodiment of a device for rotating a discharge band 2 as a discharge mechanism. The discharge zone 2 is cylindrical ,
It is installed at an angle to the horizontal plane with the charging inlet 6 side as the upper part. Further, the discharge zone 2 is configured to be rotatable 90 degrees to both sides about the axis by a rotation mechanism (not shown). Other configurations are the same as those of the first embodiment.

The present embodiment is the same as the first embodiment until the completion of preheating of the material 8 to be melted, and the discharging mechanism to the electric furnace main body 1 after the completion of preheating is different. The melt 8 is rotated 90 degrees on both sides about the axis of the discharge zone 2 and discharged to the electric furnace main body 1.

The discharge can be performed by the rotation of the discharge zone 2 without affecting the rotation of the rotary cylinder 3. The rotation of the rotary cylinder 3 only needs to control the filling of the material to be dissolved into the rotary cylinder 3, and is always stable. A filling factor could be obtained.

(Embodiment 4) FIG. 6 shows a pusher 1 at the rear of the discharge zone 2 as a discharge mechanism.
2 shows an embodiment in which 2 is arranged, and the other configuration is the same as that of the first embodiment.

The present embodiment is the same as the first embodiment up to the completion of the preheating of the material 8 to be melted, and the discharging mechanism to the electric furnace body 1 after the completion of the preheating differs. The material 8 to be melted which has been preheated and deposited in the discharge zone 2 is discharged to the electric furnace main body 1 by the pusher 12.

The discharge can be performed by the pusher 12 at the rear of the discharge zone 2 without affecting the rotation of the rotary cylinder 3, and the rotation of the rotary cylinder 3 may be controlled only by filling the rotary cylinder 3 with the material to be dissolved. A stable filling rate was always obtained.

[0022]

As is evident from the foregoing description, by rotating the rotary cylinder by introducing the lysate into rotary cylinder which constitutes the main body of the preheating zone, increasing the packing ratio of the lysate, the preheating efficiency of the lysate Was significantly improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an electric furnace having a rotating pre-tropical zone according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing a state in which a substance to be dissolved is filled into a rotating cylinder up to a ceiling.

FIG. 3 is a graph showing a relationship between an average filling rate of a substance to be dissolved in a rotary cylinder and a rate of temperature rise of the substance to be dissolved in a first embodiment.

FIG. 4 is a sectional view showing a discharge mechanism according to a second embodiment of the present invention.

FIG. 5 shows a discharge mechanism according to a third embodiment of the present invention;
(A) is a sectional view of a discharge mechanism, (b) is a cross <br/> view of X-Y cross section.

FIG. 6 is a sectional view showing a discharge mechanism according to a fourth embodiment of the present invention.

FIG. 7 is a cross-sectional view showing an example of a conventional electric furnace having a pre-tropical zone.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Electric furnace main body 1a Exhaust gas discharge port 2 Discharge zone A Preliminary tropical zone 3 Rotary cylinder 4 Exhaust gas suction fan 5 Charging zone 6 Charging inlet 7 Flue 8 Melted material 9 Conveyor for charging 10 Conveyor for discharging 11 Pusher for discharging

Claims (5)

(57) [Claims] To 1. A between the flue gas discharge outlet of the electric furnace body and the exhaust gas suction fan, in an electric furnace having a preheating zone for preheating the lysate, the preheating zone, the electric furnace body waste gas a discharge zone which is open to the scan discharge <br/> outlet, joined to the discharge zone, a rotatable rotary cylinder as the axis center, joined to the rotating cylinder, upstream of the flow direction of the melt to be to have a spout of the lysates
The rotating cylinder is inclined with respect to a horizontal plane with the charging inlet side of the material to be melted as an upper portion, and the rotating cylinder rotates.
An electric furnace equipped with a rotating pre-tropical zone , wherein the rotating cylinder is filled with a substance to be melted . 2. The electric furnace according to claim 1 , wherein a discharge mechanism is provided in the discharge zone to discharge the material to be melted into the electric furnace main body. 3. The electric device with a rotating pre-tropical zone according to claim 2 , wherein the discharge mechanism is a plate-shaped conveyor provided on the bottom surface of the discharge band so as to be slidable toward the discharge port. Furnace. 4. The discharge mechanism is 90 ° on both sides about the axis.
3. The electric furnace with a rotating pre-tropical zone according to claim 2 , wherein the rotatable discharge zone is provided. 5. The electric furnace according to claim 2 , wherein the discharge mechanism is a pusher attached to a rear part of the discharge zone.