JPH11188479A - Heating cover of molten metal container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heating cover to heat a molten metal or a molten metal container with a high-temperature combustion gas without inserting a solid burning into the molten metal container. SOLUTION: To restrain the heat releasing from the inside of a molten metal container 1, a combustion chamber 6a being filled with solid burning 7 is formed on the lower face of a cover 4, an air blowout port 12 is arranged opposite to the chamber 6a on the lower face of a cover 4 to blow in a combustion air so that a high-temperature atmosphere gas inside the container 1 is led in the chamber 6a. An air supply source 15 outside the container and the air blowout port 12a are connected by piping, and the burning 7 is ignited by the holding heat of the high-temperature atmosphere gas being led-in by the blowing air to carry out burning. Then, the generated combustion gas with a high temperature is flown into the container 1 to heat the molten metal and the molten metal container.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to heating during transportation of a container such as a ladle used for transporting molten metal such as hot metal and molten steel, and heating for suppressing a decrease in temperature of the molten metal being transported in the container. Regarding the lid.

[0002]

2. Description of the Related Art Ladles and ladle wheels (hereinafter referred to as ladles) are used as containers for transporting molten metal such as molten iron or molten steel. When transporting molten metal in the ladle, part of the heat of the molten metal is radiated from the open top of the ladle and also to the insulated brick lined in the ladle, so this is suppressed as much as possible It is necessary to.

As a method for suppressing the heat radiation from the ladle upper open surface, as shown in FIG. 5, a lid 53 having a heat insulating material 52 lined on the upper open surface of the ladle 51 during the transportation of molten metal.
It is common to attach In addition, as a method of suppressing heat radiation to the refractory lining 54 of the ladle 51, it is general to raise the temperature of the ladle 51 before receiving the molten metal as much as possible. A method of attaching the lid 53 to the upper open surface of the ladle 51 after tapping and until the molten metal is received next is a simple means. However, in this method, the heat insulating material 5 of the lid 53 is used.
2 and the heat radiation through the heat insulating material 52 are unavoidable, and since a lot of cold air flows into the ladle 51 through the gap between the ladle 51 and the lid 53, the molten metal or the ladle 51 is cooled. Is done.

As means for solving the above problem, FIG.
As shown in FIG. 7, a solid fuel 62 and an oxidant 63 are charged into a molten metal container 61, and the solid fuel 62 is ignited by the retained heat inside the container 61 or by a combustion device installed at the upper opening of the container. For keeping the temperature inside the container 61 constant by combustion of
162264) has been proposed.

[0005]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the method disclosed in Japanese Patent No. 2264, since a part of the solid fuel charged in the container remains unburned, if the solid fuel cannot be discharged and the molten metal is received, the carbon content, the sulfur content, and the like in the solid fuel are reduced. There is a problem that the molten metal is contaminated and the molten steel component changes. Further, at the time of transporting the molten metal, a similar problem occurs when a solid fuel is injected onto the surface of the molten metal in order to maintain the heat of the molten metal.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks of the prior art and eliminate the need for charging a solid fuel into a molten metal container.
The lower side of the lid of the container, that is, the combustion chamber formed in the container is filled with solid fuel, the solid fuel is ignited by the retained heat of the high-temperature atmosphere gas inside the container, and the solid fuel is burned in the combustion chamber to generate An object of the present invention is to provide a heating lid capable of heating a molten metal or a molten metal container by blowing a high-temperature combustion gas into a molten metal surface or a container.

[0007]

According to a first aspect of the present invention, there is provided a heating lid for a molten metal container, wherein a combustion chamber filled with solid fuel is formed on a lower surface of the lid for suppressing heat radiation from inside the molten metal container. An air outlet for injecting combustion air into the combustion chamber to blow in the high-temperature atmosphere gas in the molten metal container is provided on the lower surface of the lid facing the combustion chamber, and an air supply source outside the container and the air injection port are connected. The solid fuel is ignited and burned by the retained heat of the high-temperature atmosphere gas connected and drawn in. In this manner, a combustion chamber filled with solid fuel is formed on the lower surface of the lid, and the solid fuel is retained by the heat of the high-temperature atmosphere gas in the molten metal container drawn when the combustion air is blown into the combustion chamber from the air discharge port. If the fuel is ignited and burned, the generated high-temperature combustion gas flows into the container, the solid metal does not remain in the container, the molten metal and the molten metal container are heated, and the molten metal is contaminated. Can prevent the change of the molten steel component.

According to a second aspect of the present invention, there is provided a heating lid for a molten metal container according to the first aspect of the present invention, wherein the temperature of the mixed gas of the drawn high-temperature atmosphere gas and combustion air is the ignition temperature of the solid fuel. In the following cases, the solid fuel ignited in advance is charged into the combustion chamber on the lower surface of the lid. in this way,
When the temperature of the mixed gas of the drawn high-temperature atmosphere gas and the combustion air is equal to or lower than the ignition temperature of the solid fuel, the solid fuel ignited in advance is filled in the combustion chamber on the lower surface of the lid to supply the combustion air. The fuel is burned, and the generated high-temperature combustion gas flows into the container, the solid fuel does not remain in the container, the molten metal and the molten metal container are heated, and the molten steel component due to contamination of the molten metal is heated. Changes can be prevented.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The combustion chamber formed on the lower surface of the lid in the present invention is composed of side walls on both sides in the longitudinal direction in which refractories are lined on both sides, a floor and a hanging wall which is guided downward by collision of combustion gas. A combustion gas discharge port is provided on the hanging wall side, and a combustion air discharge port is provided on the lower surface of the lid at an opening opposite to the hanging wall. Further, a coke charging port which can be closed by a closing flange is provided at an upper portion of the combustion chamber. This combustion chamber has a structure in which an opening is provided in a lid, the combustion chamber is fitted into the opening, the upper part is closed with a closing flange, and coke can be replenished to each combustion chamber by removing the closing flange.

[0010] The number of combustion chambers formed on the lower surface of the lid is set at one or more places in accordance with the size of the ladle and the like.
It is advantageous to install at a plurality of places because the temperature of each part in the ladle can be made uniform.

In the present invention, the air supply source outside the container may be a combustion air fan driven by a power source of a truck that transports electricity generated by a small generator provided on the upper surface of the lid or a ladle, or on the truck. An installed high pressure air cylinder can be used.

As the solid fuel to be charged into the combustion chamber on the lower surface of the lid according to the present invention, coke, coal, briquette, charcoal, charcoal and the like can be used, but coke is the simplest operation.

The temperature in the molten metal container is low, and the temperature of the mixed gas of the combustion air and the high-temperature atmosphere gas is lower than the ignition temperature of the solid fuel, for example, the ignition temperature of coke is 550 to 65.
When the temperature is 0 ° C. or lower, the solid fuel may be charged into the combustion chamber in a state where the solid fuel is ignited in advance. The filling of the solid fuel into the combustion chamber is not particularly limited as long as the solid fuel can be charged into the combustion chamber, but the solid fuel can be taken in and out by putting the solid fuel in a basket and opening the upper closing flange to load the solid fuel. Is easy.

[0014]

Embodiment 1 Hereinafter, details of a heating lid of a molten metal container according to the present invention will be described with reference to FIGS. FIG. 1 is a side sectional view of a ladle equipped with a heating lid of the present invention, FIG. 2 is a plan view of FIG. 1, and FIG. 3 is a sectional view taken along line AA of FIG.

1 to 3, reference numeral 1 denotes an inner diameter of about 3200.
a ladle having a 200 mm refractory 3 lined inside a steel shell 2 having a height of about 3800 mm and a thickness of 30 mm, a lid 4 having a refractory 5 lined on the lower side to be attached to an upper open surface of the ladle 1, Reference numerals 6a and 6b denote combustion chambers in which coke 7 is filled in a lower surface position where two places of the lid 4 are opened, and the combustion chambers 6a and 6b are longitudinal side walls 8a and 8b lined with refractory on both sides. And floors 9a, 9b and hanging walls 10a, 10b (10b is not shown) which are guided downward by collision of the combustion gas, and combustion gas discharge ports 11a, 11b are provided on the side of the hanging walls 10a, 10b. The combustion air discharge ports 12a and 12b are arranged at the openings on the opposite sides of the hanging walls 10a and 10b. Further, on the upper part of the lid 4, a closing flange 13 is provided.
Coke filling ports 14a, 14b closed at a, 13b
The combustion chambers 6a and 6b can be refilled with coke 7 by removing the closing flanges 13a and 13b.

Reference numeral 15 denotes a small generator 1 arranged on the upper surface of the lid 4.
6 is a combustion air fan that is driven by electricity generated by driving the air flow control device 6. Air flow control valves 17a and 17b for adjusting the amount of combustion air to a predetermined flow rate, an air flow meter 18a,
It is connected to the combustion air discharge ports 12a and 12b via piping 18b. By driving the small generator 16 to generate electricity to start the combustion air fan 15, the air flow control valves 17a and 17b, the air flow meters 18a and 18b
A predetermined amount of combustion air is discharged from the combustion air discharge ports 12a and 12b through the combustion chamber 6a and supplied to the combustion chambers 6a and 6b while drawing in the high-temperature atmosphere gas in the ladle 1. The coke 7 in the combustion chambers 6a, 6b is ignited and burns, and the high-temperature combustion gas is discharged from the hanging walls 10a,
10b, the fuel gas outlet 11
a, 11b.

With the above construction, after continuous casting is completed, the empty ladle 1 from which the residue has been discharged is transported to a standby position beside the converter in order to receive the next molten steel in a converter (not shown). During 60 minutes, the upper open surface of the ladle 1 is closed with the lid 4, the closing flanges 13a and 13b are opened, and
25 kg of lump coke of 50 mm to 50 mm each in each combustion chamber 6
After filling the floors 9a and 9b of the a and 6b and closing the closing flanges 13a and 13b again, the small generator 16 is driven to generate electricity to start the combustion air fan 15 and the combustion air. Is discharged at 270 Nm ³ / Hr from the combustion air discharge ports 12 a and 12 b, respectively, and ignites and burns the coke 7 in the combustion chambers 6 a and 6 b by the retained heat of the high-temperature atmosphere gas in the ladle 1 and completes residue discharge. The average ambient temperature in the pot immediately after and the average ambient temperature in the pan when it reached the standby position next to the converter were measured. For comparison, the same temperature measurement was performed for the case where only the lid was attached and transported.

As a result, when the conventional ladle 1 was transported with only the lid attached, the average ambient temperature in the pan immediately after the completion of the discharge of the residue after the end of the continuous casting was about 1200 ° C. When it reached the horizontal standby position, it had dropped to about 800 ° C. On the other hand, when the heating lid of the present invention is applied, the average atmospheric temperature in the pot at the time of reaching the standby position next to the converter is about 1200 ° C., which is the same as immediately after the completion of the residue discharge, and the inside of the ladle 1 It was possible to suppress a drop in the ambient temperature.

Example 2 Next, using the same ladle 1 and heating lid as in Example 1, as shown in FIG. 4, the molten steel 19 received from the converter was transferred to the continuous casting facility by the ladle 1 for 30 minutes. In the meantime, the upper open surface of the ladle 1 is closed with a heating lid, the closing flanges 13a, 13b are opened, and 25 kg of lump coke having a particle size of 30 to 50 mm is placed on the floors 9a, 9b of the combustion chambers 6a, 6b, respectively. After closing the closing flanges 13a and 13b again, the small generator 16 is driven to generate electricity and the combustion air fan 15
Is started and the combustion air is discharged from the combustion air discharge ports 12a and 12a.
b and discharge at 540 Nm ³ / Hr respectively.
Combustion chambers 6a, 6b
The coke 7 in the inside was ignited and burned, the molten steel 19 was heated, and the temperature of the molten steel was lowered for 30 minutes to be transported to the continuous casting facility. For comparison, the same temperature measurement was performed for the case where only the lid shown in FIG. 5 was attached and transported.

As a result, in the case where the conventional ladle was transported with only the lid attached, the molten steel temperature was raised from 1660 ° C. to 1610 ° C. within 30 minutes of being transported from the converter to the continuous casting facility.
The temperature dropped by 0 ° C. On the other hand, when the heating lid of the present invention is applied, the temperature of the molten steel during 30 minutes of transport from the converter to the continuous casting facility is reduced from 1660 ° C. to 1615 ° C. and 45 ° C., and the temperature drop of the molten steel 18 is reduced. 5 ° C. could be suppressed.

[0021]

According to the first aspect of the present invention, the heating lid of the molten metal container forms a combustion chamber filled with solid fuel on the lower surface of the lid,
The solid fuel is ignited and burned by the retained heat of the high-temperature atmosphere gas in the molten metal container drawn when the combustion air is blown from the air discharge port into the combustion chamber, so that the generated high-temperature combustion gas enters the container. As a result, the molten metal and the molten metal container are heated without the solid fuel remaining in the container, and the change of the molten steel component due to contamination of the molten metal can be prevented.

The heating lid of the molten metal container according to the second aspect of the present invention is characterized in that when the mixed gas temperature of the drawn high-temperature atmosphere gas and the combustion air is lower than the ignition temperature of the solid fuel, By filling the combustion chamber on the lower surface of the lid, if the combustion air is supplied, the solid fuel burns, and the generated high-temperature combustion gas flows into the container,
The molten metal and the molten metal container are heated without the solid fuel remaining in the container, so that a change in the molten steel component due to contamination of the molten metal can be prevented.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a ladle equipped with a heating lid of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a side sectional view of a ladle and a heating lid used in Example 2.

FIG. 5 is a side sectional view of a conventional ladle and a lid.

FIG. 6 is an explanatory view of a method of preheating a ladle disclosed in a conventional Japanese Patent Application Laid-Open No. 61-162264.

[Explanation of symbols]

 1,51 Ladle 2 Iron 3,5,7,54 Refractory 4,53 Lid 6a, 6b Combustion chamber 7 Coke 8a, 8b Side wall 9a, 9b Floor 10a, 10b Hanging wall 11a, 11b Combustion gas discharge port 12a , 12b Combustion air discharge port 13a, 13b Closing flange 14a, 14b Coke filling port 15 Combustion air fan 16 Small generator 17a, 17b Air flow control valve 18a, 18b Air flow meter 19 Molten steel 52 Insulation material 61 Molten metal container 62 Solid fuel 63 Oxidizer

Claims (2)

[Claims] 1. A combustion chamber filled with a solid fuel is formed on a lower surface of a lid to suppress heat radiation from inside a molten metal container, and combustion air is drawn into the combustion chamber so as to draw a high-temperature atmosphere gas in the molten metal container. An air outlet for blowing air is provided on the lower surface of the lid facing the combustion chamber, and an air supply source outside the container is connected to the air outlet by piping, and solid fuel is ignited by the retained heat of the high-temperature atmosphere gas drawn into the blown air. A heating lid for a molten metal container characterized by burning. 2. When the temperature of a mixed gas of the drawn high-temperature atmosphere gas and combustion air is equal to or lower than the ignition temperature of the solid fuel,
2. A heating lid for a molten metal container according to claim 1, wherein a solid fuel ignited in advance is filled in a combustion chamber on a lower surface of the lid.