TWI385352B - A ladle preheating apparatus - Google Patents

Description

Pouring bucket preheating device

The present invention relates to a bucket preheating device for preheating the internal ambient gas of an empty ladle.

In a ladle that is conveyed by receiving molten steel, in order to preheat the internal environment gas, a regenerative burner is generally used. The regenerative burner has a regenerator and a main nozzle through which the combustion air and the combustion exhaust gas can pass, and the heat of the combustion exhaust gas recovered by the regenerator is used as a preheating source of the combustion air. Regarding this regenerative burner, for example, Patent Document 1 and Patent Document 2 are known.

Patent Document 1 discloses a single-stage regenerative burner in which a regenerative burner is provided with a plurality of regenerators. Further, at each specific time, the regenerator through which the combustion exhaust gas passes and the regenerator through which the combustion air passes are switched, and the heat recovered by the combustion exhaust gas through the regenerator is used to heat the combustion air.

However, the capacity of a single-type regenerative burner has its limits, and when it is used in steelmaking equipment, it is difficult to be used as a preheating operation for a large ladle. In order to solve this problem, one of the alternate combustion type regenerative burners is known.

Patent Document 2 discloses an alternating type regenerative burner, and in a heating operation stage of a molten metal container such as a ladle, a cover of the pair of regenerative burners is provided, and is covered in an opening of the melt container. The nozzles of the regenerative burners alternately perform the injection and exhaust of the flame at a certain timing.

At this time, the main nozzles of the pair of regenerative burners are arranged in the radial direction at a predetermined distance from the center of the cover. Further, each of the main nozzles is opened downward. Therefore, the flame of the regenerative burner is ejected in the vertical direction from the eccentric position of the center of the cover by the main nozzle.

(Patent Document 1) Japanese Patent Laid-Open Publication No. 2001-27412

(Patent Document 2) Japanese Patent No. 3680252

However, in the preheating operation of the conventionally-operated mixing bucket of the regenerative burner, the regenerative burner from the combustion side ejects the flame in the vertical direction, so that the lower side of the regenerative burner on the combustion side The area is heated to a higher temperature than the area on the lower side of the non-combustion side regenerative burner.

Further, since the pair of regenerative burners are alternately combusted, often only one of the regenerative burners is combusted, and the combustion side is switched at a constant interval. Therefore, the area heated by the high temperature constantly changes, the internal temperature of the melt container is unstable, and the internal environment gas cannot be uniformly heated. In particular, in the preheating operation of the pouring bucket for receiving the molten steel, it is necessary to keep the molten steel material in a stable state, and it is necessary to eliminate the temperature difference of the internal environmental gas.

The present invention has been made in view of the above problems, and an object thereof is to provide a bucket preheating apparatus capable of uniformly preheating an internal environment gas of an empty ladle.

The bucket preheating device of the present invention is provided with a bucket cap that can close the opening portion of the ladle which is conveyed by the molten steel material, and the bucket cap is installed with one of the alternate combustions for preheating the internal environment gas of the empty drum. For a regenerative burner, the regenerative burner is provided with a burner nozzle in which a flame can be ejected in the ladle, and in the preheating device of the ladle, the pair of burner nozzles are from the barrel cap The center is disposed at an equally spaced position in the diameter direction, and at the same time, in order to uniformly preheat the inside of the ladle, a flame is ejected from the center of the lid to descend on the axis of the height direction.

The aforementioned pair of regenerative burners are arranged to be point-symmetric with respect to each other with respect to the center of the aforementioned tub cover.

The longitudinal side portions of the pair of regenerative burners are arranged to face each other.

The bucket preheating device of the invention can uniformly preheat the internal environment gas of the empty ladle.

Hereinafter, a suitable embodiment of the bucket preheating apparatus of the present invention will be described in detail with reference to the accompanying drawings. As shown in FIGS. 1 to 4, the ladle preheating apparatus 1 of the present embodiment basically has a tub 2 that can be transported by receiving molten steel, and is provided with a tub cover 4 that can close the opening 3 thereof. In order to preheat the internal environment gas of the empty ladle 2, it is installed with one of the alternating combustion right side regenerative burner 5 and the left regenerative burner 6, while the regenerative burners 5, 6 are provided with the pouring The burner nozzles 5a, 6a of the flame f can be ejected in the tub 2, and in the ladle preheating device 1, a pair of burner nozzles 5a, 6a are disposed at equal intervals from the center C1 of the tub cover 4 at a diameter In the direction, at the same time, in order to uniformly preheat the inside of the ladle 2, a flame f is ejected from the axis X of the center C1 of the tub cover 4 descending in the height direction (vertically downward).

The pair of regenerative burners 5, 6 are arranged to be point-symmetric with respect to each other with respect to the center C1 of the tub cover 4.

The ladle 2 that is subjected to the high-temperature molten steel material and transported to the next step is formed into a substantially circular shape, and an opening portion 3 that can access the molten steel material is formed above the ladle 2. Although the ladle 2 is generally 3 m in diameter and 3.5 m in depth, the size of the ladle 2 is not limited thereto, and it may be formed to be larger or smaller than this.

The nozzle 2 has an opening portion 3 and a substantially circular shape having a substantially planar shape, and is provided with a tub cover 4 that can open and close the opening portion 3 so as to be closable. On the upper surface of the lid 4, at approximately equal intervals in the circumferential direction, four wire holes 7 through which a wire W can be inserted are provided. When the wire W is inserted into the wire hole 7, the lid 4 is opened and closed by a crane or the like. The wire hole 7 is not limited to four, as long as the bucket cover 4 can be lifted in a balanced manner.

On the top of the lid 4, in order to preheat the internal ambient gas of the empty ladle 2 in front of the steel, an alternating right side regenerative burner 5 and a left regenerative burner 6 are mounted.

The regenerative burners 5 and 6 each have burner nozzles 5a and 6a, and communication passages 5b and 6b, and heat storage bodies 5c and 6c. Specifically, the burner nozzles 5a and 6a that can eject the flame f are provided at the tips of the regenerative burners 5 and 6, and the communication passages 5b and 6b are connected to the rear of the burner nozzles 5a and 6a. Therefore, the communication passages 5b and 6b are connected to the rear side of the regenerative burners 5 and 6, and the regenerators 5c and 6c through which the combustion air and the exhaust gas pass are provided.

Although not shown, an air supply pipe that can supply combustion air and an exhaust pipe that discharges exhaust gas are connected to the rear of the heat storage bodies 5c and 6c. In order to allow the combustion air and the exhaust gas to flow therein, the heat storage bodies 5c and 6c are stacked, for example, a heat storage material having a ceramic honeycomb structure, or a plurality of ceramic spherical heat storage materials, or a plurality of ceramics stacked. The tube or the like is composed of a weight.

The burner nozzles 5a and 6a of the regenerative burners 5 and 6 are connected to the fuel supply pipe 8 at the upper portion thereof. The fuel supply pipe 8 supplies a fuel such as a liquid or a gas. Inside the burner nozzles 5a and 6a, a pilot burner (not shown) is provided, and the fuel supplied by the primary fuel supply pipe (not shown) and the primary air supply pipe (not shown) The air supplied is often generated once in the burner nozzles 5a, 6a. The burner nozzles 5a and 6a of the regenerative burners 5 and 6 use a primary flame of a pilot burner (not shown) as an ignition source, and the fuel and fuel air supplied by the fuel supply pipe 8 are directed toward A flame f is ejected from the pouring tub 2. The pilot burners need not be provided in the burner nozzles 5a, 6a, and may be provided, for example, next to the burner nozzles 5a, 6a.

The regenerative burners 5, 6 are alternately combusted. For example, the burner nozzle 5a of the right side regenerative burner 5 in the non-combustion state sucks the high-temperature exhaust gas burned by the left-side regenerative burner 6 in the combustion state, and the exhaust gas is made by the communication path 5b. The regenerator 5c is heated and then exhausted from the exhaust pipe. When the right regenerative burner 5 is switched to the combustion state, the combustion air supplied from the air supply pipe is heated to a high temperature by the heated regenerator 5c, and is supplied from the fuel supply pipe 8. The fuel is ignited by a primary flame of a pilot burner (not shown), and a high temperature flame f is ejected from the burner nozzle 5a into the ladle 2.

Here, as shown in FIG. 2, when one diameter direction of the tub cover 4 is made into B, and the upper side is made into the upper side, and the lower side is made into the lower side, the regenerative burners 5 and 6 are used. The right regenerative burner 5 is attached to the right side of the respective equidistant positions of the center C1 in the diameter direction B, and the left regenerative burner 6 is attached to the left side. Further, the right side regenerative burner 5 and the left regenerative burner 6 have their longitudinal directions parallel to each other and are provided at approximately a right angle with respect to the diameter direction B of the tub cover 4.

As described in detail, the right regenerative burner 5 has a burner nozzle 5a positioned at a proper interval on the right side from the center C1 in the diameter direction B, and its longitudinal direction is substantially at right angles to the diameter direction B, and The lower side of the burner nozzle 5a is disposed toward the heat storage body 5c. Further, in the left regenerative burner 6, the position of the burner nozzle 6a is set to the left side from the center C1 in the diameter direction B, and is equally spaced from the burner nozzle 5a on the right side, and the longitudinal direction thereof is substantially perpendicular to the diameter direction B. At a right angle, it is disposed toward the heat storage body 6c on the upper side of the burner nozzle 6a.

In the present embodiment, the arrangement of the regenerative burners 5, 6 is set to the longitudinal direction of the right regenerative burner 5 and the left regenerative burner 6 and the diameter direction B of the lid 4 with respect to the lid 4 It is substantially at right angles, but the center C1 of the lid 4 is not limited to the above setting as long as the regenerative burners 5, 6 are arranged to be point-symmetric with each other.

Further, the burner nozzles 5a, 6a are set to have an angle toward the axis X, and the flame f ejected from the burner nozzles 5a, 6a is directed toward the axis X from the center C1 of the tub cover 4 in the height direction downward. Squirting. In particular, it is preferable to set the burner nozzles 5a and 6a such that the flame f is angled toward the intermediate position C2 in the depth direction of the ladle 2.

Next, the action of the ladle preheating apparatus 1 of the present embodiment will be described. In use, a pair of regenerative burners 5, 6 mounted on the lid 4 of the empty ladle 2 are directed toward the axis X in the ladle 2. The flame f is ejected alternately and burns. After preheating for a predetermined period of time, the steel drum W is lifted by lifting the lid 4 by a crane or the like, and the molten steel material is received and conveyed toward the next step.

The bucket preheating device 1 of the present embodiment is such that the burner nozzles 5a, 6a are angled, and the flame f is directed toward the axis X from the center C1 of the lid 4, and Compared with the preheating operation of the ladle preheating device with a pair of alternating regenerative burners, the flame f is not ejected from the central axis X to the left or right side, but can be sprayed on the central axis of the ladle 2 The peripheral portion on the axis X is heated and allows the inside of the ladle 2 to be uniformly preheated.

Further, by ejecting the high-temperature flame f toward the peripheral portion of the intermediate position C2 in the depth direction of the ladle 2, as shown in FIG. 1, the hot air swirls inside the ladle 2. Thereby, heat can be distributed throughout the corners of the ladle 2, and the internal ambient gas of the ladle 2 can be heated more efficiently at a uniform temperature.

In the present embodiment, when the regenerative burners 5 and 6 are arranged to be point-symmetric with respect to the lid 4, the regenerative burners 5 and 6 containing one of the weights to the heat accumulators 5c and 6c can be made relatively The bucket cover 4 is balancedly arranged. Therefore, it is not necessary to provide a large-scale device such as a balance weight for adjusting the weight balance of the lid 4, and a simple method such as lifting the wire on several portions of the lid 4 can be used. The lid 4 is opened and closed in a balanced manner. Further, since the tub cover 4 can be weight-balanced, it is possible to prevent deformation of the tub cover 4 even if, for example, ribs or the like are not formed on the tub cover 4 for preventing deformation.

In the present embodiment, a pair of regenerative burners 5, 6 are used. Therefore, it is also applicable to a large ladle as compared with the configuration described in the prior art in which a single-stage regenerative burner is provided at the center of the lid. Specifically, although the single-type type can only ensure a capacity of up to 200,000 Kcal/hr, a pair of regenerative burners 5 and 6 can secure a capacity of 500,000 Kcal/hr or more, which can correspond to a small or even large size. The barrel 2 is poured to uniformly preheat the inside of the ladle 2.

Next, a first modification of the bucket preheating apparatus 1 of the present embodiment will be described. In the first modification, the pair of regenerative burners 5 and 6 are disposed on the tub cover 4 so as to face each other in the longitudinal direction side portions thereof.

As will be described in more detail with reference to Fig. 5, the right regenerative burner 5 is the same as that of Fig. 2, and the burner nozzle 5a is disposed in the diameter direction B at an appropriate interval from the center C1 of the lid 4. In particular, in the present modification, the longitudinal direction of the right regenerative burner 5 has a constant angle with respect to the diameter direction B and is arranged in parallel with respect to the other diameter direction D. Further, the burner nozzle 6a of the left regenerative burner 6 is disposed in the diameter direction B from the center C1 of the tub cover 4 and the right burner nozzle 5a at equal intervals, and the longitudinal direction thereof is arranged in the diameter direction D in parallel. That is, it is disposed in parallel with the right side regenerative burner 5.

Thereby, the regenerative burners 5 and 6 can be accommodated in the tub cover 4 without being exposed from the outer periphery of the tub cover 4. Therefore, it is not necessary to have a large space to set the bucket preheating device 1. In particular, when comparing the smaller size of the bucket preheating device 1 and the like with respect to the tub cover 4 such as the regenerative burners 5, 6, the installation space of the ladle preheating device 1 can be made small by the above configuration. Chemical. Further, since the regenerative burners 5, 6 are not exposed from the tub 4, they can freely set the mounting position of the wire holes 7.

Next, a second modification of the bucket preheating apparatus 1 of the present embodiment will be described. In the second modification, as shown in Fig. 6, the fuel supply pipe 8' is provided between the right burner nozzle 5a and the left burner nozzle 6a. Further, the spark plug 9 is provided beside the fuel supply pipe 8'.

The high-temperature combustion air a alternately ejected from the right burner nozzle 5a and the left burner nozzle 6a, when the fuel for the combustion air a and the fuel supply pipe 8' is ignited by the spark plug 9, is directed toward the ladle 2 A flame f is generated on the axis X of the central axis.

By the flame f described above, the peripheral portion on the axis X of the central axis of the ladle 2 is heated, and the inside of the ladle 2 can be uniformly preheated. Further, by ejecting the high-temperature flame f to the peripheral portion of the intermediate position C2 in the depth direction of the ladle 2, the hot air swirls inside the ladle 2. Thereby, as in the above embodiment, high-temperature heat can be distributed throughout the corners of the ladle 2, and the internal ambient gas of the ladle 2 can be heated more efficiently at a uniform temperature.

1. . . Pouring bucket preheating device

2. . . Pour bucket

3. . . Opening

4. . . Bucket cover

5, 6. . . Regenerative burner

5a, 6a. . . Burner nozzle

5b, 6b. . . Connected road

5c, 6c. . . Heat accumulator

7. . . Wire hole

8, 8’. . . Fuel supply pipe

9. . . Spark plug

a. . . Combustion air

B, D. . . Diameter direction

C1. . . Bucket center

C2. . . Middle position of the lid depth

f. . . flame

W. . . Steel wire

X. . . Axis

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a side cross-sectional view showing a preferred embodiment of a bucket preheating apparatus of the present invention.

Figure 2 is a plan view showing the ladle preheating device of Figure 1.

Figure 3 is a cross-sectional view taken along line A-A of Figure 2.

Fig. 4 is a side view showing the state in which the bucket lid of Fig. 2 is suspended by a crane.

Fig. 5 is a plan view showing a first modification of the bucket preheating apparatus of the present invention.

Fig. 6 is a side sectional view showing a second modification of the bucket preheating device of the present invention.

1. . . Pouring bucket preheating device

2. . . Pour bucket

3. . . Opening

4. . . Bucket cover

5. . . Regenerative burner

5a. . . Burner nozzle

5b. . . Connected road

5c. . . Heat accumulator

6. . . Regenerative burner

6a. . . Burner nozzle

6b. . . Connected road

6c. . . Heat accumulator

8. . . Fuel supply pipe

C2. . . Middle position of the lid depth

f. . . flame

X. . . Axis

Claims (2)

A bucket preheating device, characterized in that: a pair of left and right combustion air ejection nozzles are provided for closing a lid of an opening of a pouring bucket that is conveyed by a molten steel material, and the inside of the empty pouring bucket is uniformly formed for the purpose of generating a preheating flame having a regenerator that heats the supplied combustion air by heating the exhaust gas to be sucked, and alternately ejects combustion air into the pail; and a fuel supply pipe provided in the Between the combustion air ejection nozzles, fuel is supplied into the ladle so that a flame is ejected from the center of the tub cover toward the axis falling in the height direction; and the pair of left and right combustion air ejection nozzles are disposed. To be inclined toward the above-mentioned axis, the flame is directed toward the intermediate position in the depth direction of the ladle, and the hot air caused by the ejected flame is swirled inside the ladle. The ladle preheating apparatus according to claim 1, wherein the pair of combustion air ejection nozzles are disposed at equal intervals in a diameter direction from a center of the tub cover.