JPS62244569A - Heating method for vessel for molten steel - Google Patents

Abstract

PURPOSE:To uniformly heat the inside of a vessel for a molten steel and to reduce fuel unit for heating up by vertically moving a combustion device mounted to a cap device of the vessel and drying and preheating the inside of the vessel by the combustion flame thereof. CONSTITUTION:The cap device 2 is put on an upper aperture of the vessel 1 such as ladle and the combustion device 21 and flue 22 are provided to the cap device 2. The combustion device 21 is vertically moved in the vessel 1 during the drying and preheating in the vessel 1 by a lifting deice 3. The combustion flame is generated in the vessel 1 from the combustion device 21 according to the above-mentioned constitution and the combustion device 21 is lifted to dry and preheat the inside of the vessel 1. The exhaust gas generated in this stage is discharged through the flue 22 and the heat of the exhaust gas is recovered by a recuperator 221 provided to the flue 22. Part thereof is used for preheating the supply air to the combustion device 21. The inside of the vessel 1 is thereby uniformly heated and thermal efficiency is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [A] Field of Industrial Application The present invention relates to a method for heating a container such as a ladle for holding or transporting molten metal such as hot metal or molten steel.

Port C) Prior Art A ladle is used as a container for holding or transporting hot metal or molten metal in a molten steel valley. This ladle is lined with an insulating material such as brick, and must be dried and heated to a high temperature before receiving the molten metal.

To this end, conventionally, a combustion device such as a burner is attached to the upper opening of the ladle from the outside to generate a combustion flame, and radiant heat transfer from the flame is used to dry and raise the temperature to a predetermined temperature. therefore.

The flame flows in one direction from the opening of the ladle downwards, making it difficult to dry and heat up evenly and at high speeds. Furthermore, many hot gases dissipate without transferring heat to the ladle. A lot of new cold air flows in and cools the inside of the rll pan. Therefore.

Combustion device installation + (I!l (Upper) is at a high temperature, while the anti-combustion device side (lower) is in the direction of low f grade VC, and it takes a large amount of fuel and time to bring the lower part to the specified temperature. It will take a while.

To solve this problem, attach a lid to the top of the ladle.

A method has been proposed in which a burner is inserted into the ladle by penetrating the lid, and the exhaust gas in the ladle is exhausted to the outside through a flue.

However, in this method, the burner is fixed to the lid to heat up and dry, so the tip of the burner can be heated to a high temperature, but the temperature of the other parts is low.

Inconsistency in the temperature inside the ladle occurs. This results in insufficient drying, especially in the low temperature area at the bottom of the pot. In order to solve this lack of drying, the atmospheric temperature inside the pot is raised, which increases the amount of fuel used.

On the other hand, in order to solve the problem of insufficient heating at the bottom of the pot, a long flame burner (
(Japanese Patent Application Laid-Open No. 1188-1988)
Publication No. 7) has been proposed. However, since this method also completely fixes the burner to the lid, the tip of the burner is overheated and the ladle explodes immediately, leaving the rest of the burner at a low temperature.

Furthermore, if the lid opening/closing device is of a vertical drive type, the ladle can be moved by a crane after the drying session heats up.

If the lid opening/closing device is opened on one side, the long flame burner hits the ladle, making it impossible to move the ladle with a crane.

In order to improve this drawback, it is necessary to separate the lid opening/closing device and the long flame burner. this is.

The work becomes complicated when moving the ladle.

(c) Problems to be Solved by the Invention The problems to be solved by the present invention are to uniformly heat the inside of the container for charging molten metal, prevent explosions caused by the occurrence of a localized high basin portion, and The aim is to reduce the unit consumption of heating fuel.

B) Means for Solving the Problems The method of heating a molten steel container of the present invention involves generating a combustion flame in the container from a combustion device attached to the lid of the steel container to dry and preheat the container. In the method of heating a molten steel container, the inside of the container is heated while changing the distance of 4 from the bottom of the container to the tip of the fuel m3 device,
The above-mentioned 1 river problem has been solved.

(e) Implementation example FIG. 1 is an explanatory diagram showing the method of the present invention.

A lid device 2 is placed on the upper opening of the ladle container 1. Is container 1 hot metal or Keiko 4? It is a plow that holds or transports molten gold. The container 1 must be dried and heated to a high temperature before receiving the molten gold.

The lid device 2 is made up of a combustion device 21 and a flue 22. The combustion device t211d may be a conventional long burner.

The combustion device 21 uses, for example, coke oven gas as fuel. The flue 22 guides exhaust gas generated within the container to the outside of the container. A recuperator 221 is provided in the middle of the flue 22.

Recovers heat from exhaust gas. A portion of the heat recovery is used to preheat the feed air to the combustion device 1.

The combustion device No. 1 uses a lifting device 6 to dry and dry the inside of the container 1.
It moves up and down inside the container 1 when the temperature rises. The lifting device 6 may be a single hoist or a hydraulic cylinder.

The vertical distance and vertical cycle of the combustion device 21 are determined empirically based on the repair status of the container (container history), its rotation rate (standby time), and the like.

Next, an example in which the method of the present invention was actually applied to a ladle will be shown below.

In the full-length pot 1 with a capacity of 161 J ton/CH, a long burner is used as the heating device 21 to heat the pot 1000 mm from the pot 1 and 300 mm (60 minute pitch (for example, the first 60 minutes) between the pot 1 and the bottom. It was driven for 60 minutes at 1,000 liters from the bottom of the pot, and at 3,000 m from the bottom of the pot.

the result? r: Shown in FIG. 2 and Table 1. Pot bottom temperature If
(B C1mm from the inner surface) was rarely 550℃ at the end of drying with the conventional method, but with the method of the present invention, it rose significantly to 800℃, and the temperature inside the pot was 1000℃ with the conventional method. However, in the method of the present invention, 9L]O'
C, and the internal temperature difference was significantly improved. The heating time for drying to satisfy the pot bottom temperature e550℃ was 24 f(r) in the conventional method, but it was 16 h in the method of the present invention.
r, and before using fuel gas, it is only about half of the conventional amount.

・In particular, in order to raise the temperature at the bottom of the pot, the shorter the distance from the bottom of the pot to the tip of the burner, the more effective it is to raise the temperature.
When the temperature rises locally, the bricks at the bottom of the pot explode, causing
4.4 Not possible [This will be the fth item. On the other hand, if the distance from the bottom of the burner to the tip of the burner is greater than the bottom of the pot, the rise of the bottom of the pot will be poor, exhaust gas loss will increase, and thermal efficiency will deteriorate.

Therefore, in the present invention, in order to prevent local heating of the bottom of the pot, the upper part of the burner is turned on.

This improves thermal efficiency and saves fuel gas by shortening heating time.

(F) Effects According to the method of the present invention, it is possible not only to simply save energy, but also to equalize the temperature of the container lining bricks, prevent explosions, and extend the life of the wear bricks. Furthermore, since the heating time can be shortened, the unit consumption of heating fuel can be reduced, and the container can be operated more freely.

The method of the present invention can be applied not only to the steel receiving ladle but also to the application of containers for high-temperature molten materials such as the fA ladle, torpedo main tree, and tundish.

[Brief explanation of drawings]

FIG. 1 is a detailed explanatory diagram of the present invention. FIG. 2 is a graph showing the effect of the method of the present invention. 1: Six vessels 2: Lid device 6: Lifting device 21: Combustion device 22: Flue 221: Recuperator.

Claims (1)

[Claims] A heating method for a molten steel container in which a combustion flame is generated in the container from a combustion device attached to a lid device of the molten steel container to dry and preheat the inside of the container. A method for heating a molten steel container, characterized by heating the inside of the container while changing a distance.