JPS6135340Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a heating device for heating the lining of a ladle.

Ladles used for receiving molten steel use refractory bricks as an lining, so they must be dried after construction, and the ladle is often preheated to a high temperature of 1000°C or higher before use. Conventionally, the ladle heating device used for drying or preheating the lining has been a simple device with a burner attached to a lid attached to the ladle, but the heat exchange rate was poor and a large amount of heat was used. needed fuel.

This idea solves the above-mentioned conventional drawbacks.
The present invention aims to provide a heating device that can efficiently heat a ladle by passing combustion gas from a burner through an air-permeable solid and converting the sensible heat of the combustion gas into solid radiant heat.

In this invention, the term "breathable solid" refers to a solid made of a fire-resistant material such as metal or ceramic, and formed into a shape having air permeability such as a net, honeycomb, fiber, or porous shape and having an appropriate thickness. This breathable solid can be considered equivalent to a large number of small spheres or small diameter wires, so its effective surface area is extremely large, and when gas is passed through this breathable solid, the convective transfer coefficient is extremely large. .

An embodiment of this invention will be described below with reference to the drawings.

In the figure, 1 is a ladle and 2 is its nozzle hole.
Reference numeral 3 denotes a lid, which is a top plate made of a steel plate with appropriate reinforcement and lined with a heat insulating material, and 4 is a sealing material such as ceramic fiber attached to the portion that engages with the ladle 1. The lid 3 is configured to be detachably attached to the ladle 1 by means of a lifting device (not shown). 5 is a burner attached to the lid 3 with the flame forming side facing the ladle side; 6 is a fuel supply port thereof; 7 is an air supply port thereof; and 8 is an exhaust port bored in the lid 3. Reference numeral 9 denotes a partition made of an air-permeable solid, and in this embodiment, ten layers of stainless steel wire mesh (wire diameter 0.6 mm, 16 meshes) are laminated to form a ventilation plate shape, which is formed into a shell shape. The partition 9 includes a conical side wall portion 10 facing the side wall surface of the ladle 1, a notched disc-shaped bottom wall portion 11 facing the bottom surface of the ladle 1, and a flame forming portion 1 of the burner 5.
2, and a lid 3 that partitions between the flame forming part 12 of the burner and the exhaust port 8.
installed on. Reference numeral 14 denotes a heat exchanger for preheating the air provided between the partition 9 and the lid 3, which has a bent tubular shape and also serves as a support member for the partition 9. 1
5 is a wire that connects the partition 9 and the heat exchanger 14. 16 is an air inlet of the heat exchanger 14, and 17 is an air outlet, which is connected to the air supply port 7 of the burner.

In order to heat the ladle with the device configured as described above, combustion air is introduced into the air inlet 16 with the lid 3 attached to the ladle 1 as shown in the figure, and fuel is supplied to the burner 5. Combustion is performed at As the fuel gas of about 1500°C generated by this combustion flows between the partition 9 and the ladle 1, it heats the ladle 1 by convection heat transfer, passes through various parts of the partition 9, and is discharged from the exhaust port 8. Ru. When the combustion gas passes through the partition 9, the partition 9, which is made of an air-permeable solid with a large surface area, is heated to a high temperature by convection heat transfer, and the ladle 1 is heated by radiation heat transfer from the high-temperature partition 9. be done. The combustion gas after passing through partition 9 is 400
Although the temperature has decreased by approximately .degree. C., the heat exchanger 14 is further heated by convection heat transfer, so preheated air is supplied to the burner 5, and fuel can be saved.

In general, the radiation injection capacity of a solid is sufficiently larger than that of a gas, and since the partition 9 is made of a breathable solid and has an extremely large heat transfer coefficient with the combustion gas, the sensible heat of the combustion gas is transferred to the radiation heat of the partition 9. It is efficiently converted and used effectively for heating the ladle 1. According to the experimental results of the inventors using a ladle with an inner diameter of 900 mm and a height of 1200 mm in two cases with and without partitions 9 using the above device, the exhaust gas temperature at the exhaust port 8 is approximately 1050 degrees Celsius in the case with partitions;
It can be seen that the sensible heat of the exhaust gas, which was conventionally released into the atmosphere at approximately 1250°C without a partition, is effectively used to heat the ladle according to the present invention. In this experiment, the amount of fuel (kerosene) required to heat ladle 1 to the same temperature (1000°C) was approximately 85% less with partitions than without partitions, achieving significant fuel savings. did it. In addition, this breathable solid has the characteristic that even if heat is removed (heat removal) on the gas downstream side of the breathable solid, the temperature on the gas upstream side hardly changes. Even if it is installed in the space inside the ladle on the side, the heating efficiency will not decrease.

In the above embodiment, since the partition 9 is provided with the side wall portion 10 and the bottom wall portion 11 that face the ladle 1, the ladle 1 can be heated almost uniformly and efficiently, but the shape of the partition 9 is different from that of the burner. Shapes other than those described above may be used depending on the arrangement of the partitions 9, the partitions 9 may be made of other breathable solid materials, and the heat exchangers 14 may also be of other types.

As explained above, according to this invention, a partition made of air-permeable solid is provided on the lid attached to the ladle to separate the burner and the exhaust port, so that the radiant heat transfer of the air-permeable solid is improved. This addition provides a ladle heating device with high thermal efficiency, and together with the provision of a heat exchanger for air preheating in the space between the partition and the lid, significant energy savings can be achieved.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a ladle heating device showing an embodiment of the invention, Fig. 2 is a sectional view taken along the line A-A in Fig. 1, and Fig. 3 is a partial plan view taken along the line B-B. be. 3... Lid, 5... Burner, 7... Air supply port,
8...exhaust port, 9...partition, 14...heat exchanger,
17...Air outlet.

Claims (1)

[Scope of utility model registration request] a lid detachably attached to the ladle; a burner attached to the lid with the flame formation side facing the ladle; an exhaust port drilled in the lid; a flame formation side of the burner and the exhaust port. a partition made of a breathable solid attached to the lid to separate the space between the partition and the lid, and an air preheating heat source provided in the space between the partition and the lid and having an outlet pipe connected to the air supply port of the burner. A ladle heating device comprising an exchanger.