JPH0740825Y2 - Oxygen-fuel burner for steelmaking - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oxygen-fuel burner for steelmaking for melting a material to be melted, for example, scrap in an arc furnace.

[0002]

2. Description of the Related Art In an arc furnace in which an arc is generated between electrodes or between an electrode and a material to be melted, and the material to be melted is melted by utilizing the arc heat or radiant heat, the material to be melted is put into the arc furnace. In order to improve the melting efficiency of scrap, it is necessary to constantly apply combustion flame to cold scrap to promote the collapse of scrap. Therefore, conventionally, there have been proposed one in which many burners are provided on the furnace wall and one in which the burner and the swinging device are combined.

[0003]

[Problems to be Solved by the Invention] However, the former has a problem that the equipment cost rises and the handling becomes complicated, and the latter has a malfunction of the swinging device due to the adhesion of metal to the burner insertion part. However, there is a problem in that it takes a lot of labor to remove the adhered metal.

[0004]

Therefore, the oxygen-fuel burner for steelmaking of the present invention has been made to solve the above-mentioned problems. An oxygen nozzle extending obliquely downward and an oxygen nozzle are formed in one metal block. In addition to forming a plurality of injection ports that arrange fuel nozzles that extend horizontally in the same vertical plane as oxygen and fuel injected from these nozzles intersect,
A second oxygen nozzle extending obliquely downward is provided between these ejection ports, and the ejection port and the second oxygen nozzle are arranged so that the mutual intervals widen in a fan shape toward the ejection side.

[0005]

According to the above oxygen-fuel burner for steelmaking, oxygen and fuel injected from each injection port are expanded in a fan shape. Therefore, the cold scrap thrown into the furnace can be uniformly heated and melted as in the case of the device in which the burner and the swinging device are combined. Further, the oxygen injected from the second oxygen nozzle melts the scrap and further promotes the melting.

[0006]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 3 show an oxygen-fuel burner 1 for steelmaking (hereinafter referred to as "burner 1") according to the present invention,
The main body 2 of the burner 1 is made of a substantially rectangular metal block. Inside the main body 2, the oxygen header 3 is provided in the longitudinal direction.
And a fuel header 4 are formed, and one ends of these are connected to an oxygen supply pipe 5 and a fuel supply pipe 6, respectively. The oxygen header 3 has an oxygen supply chamber 7 extending upward at predetermined intervals.
Oxygen nozzles 8 are formed obliquely downward (depression angle θ ₁ ) from the oxygen supply chamber 7 toward the front surface of the main body 2, and the oxygen nozzles 8 are arranged radially to form the oxygen nozzles 8. The oxygen injected from the fan spreads out like a fan. On the other hand, in the fuel header 4, a fuel nozzle 9 extending substantially horizontally toward the front surface of the main body 2 is formed on the vertical plane including the oxygen nozzle 8, and the tip end of the fuel nozzle 9 and the oxygen nozzle 8 are formed. The injection port 10 is configured. The spread angle θ ₂ of the oxygen nozzle 8 is 30 to 4
5 ° is suitable. In addition, in the main body 2, second oxygen supply chambers 11 are formed between the oxygen supply chambers 7, respectively. From the second oxygen supply chambers 11 toward the front surface of the main body 2 like the oxygen nozzles 8. A second oxygen nozzle 12 extending obliquely downward is formed, and each second oxygen supply chamber 11 is connected to an oxygen supply pipe 13. Furthermore, a cooling water passage 14 is formed in the front portion of the main body 2, and both ends thereof are connected to a cooling water supply pipe 15 and a cooling water discharge pipe 16.

The burner 1 is, as shown in FIGS.
Attached to the side wall 18 of the arc furnace 17 at predetermined intervals, the oxygen supply pipes 5 and 13 and the fuel supply pipe 6 are connected to an oxygen supply source and a fuel supply source (neither shown), and these supply pipes 5 , 6, 13 are connected to an air supply source such as a blower via a switching valve. Also, the cooling water supply pipe 1
5 and the cooling water discharge pipe 16 are respectively connected to a cooling water passage (not shown). The installation height of the burner 1 should be as high as possible so that the intersection 21 of the extension line 19 of the oxygen nozzle 8 and the sill level 20 is located outside the pitch circle 23 of the electrode 22 and avoids the influence of splash and metal. preferable.

In the arc furnace 17 in which the burner 1 is installed as described above, a melted material such as scrap (not shown) is charged into the furnace, a predetermined voltage is applied to the electrode 22, and the oxygen nozzle 8 and Oxygen and fuel are injected from the fuel nozzle 9 and burned. Then, between the electrodes 22 or the electrodes 2
The object to be melted is melted by the arc heat or the radiant heat generated between the object 2 and the object to be melted, and the object to be melted is extensively heated by the combustion flame spreading in a fan shape along the arrangement direction of the oxygen nozzle 8. , Its dissolution is promoted. Further, when a predetermined time has elapsed from the start of preheating by the combustion flame (specifically, after 30 to 60 seconds have elapsed), the second oxygen nozzle 1
Oxygen is injected from 2 to heat the material to be melted located between the flames to melt and melt the material to be melted efficiently. Then, when the dissolution processing of the substance to be dissolved is completed, the supply of oxygen to the oxygen nozzle 8 and the second oxygen nozzle 13 and the supply of fuel to the fuel nozzle 9 are cut off, and air is supplied from the blower instead. . However, this air supply is not essential.

The above burner (wide frame burner),
When the arc furnace was equipped with a single-frame burner with only one injection port on the burner body to melt scrap, the burner according to the present invention showed about 10% less burner than the single-frame burner as shown in FIG. 1.3 times (4.5 / 3.4
≈1.3) The result was that the dissolution efficiency was good.

[0010]

As is apparent from the above description, in the burner according to the present invention, since oxygen and fuel are injected in a fan shape from a plurality of injection ports provided in the burner, one burner can cover a wide area. Similarly, the material to be melted can be heated. Also,
Oxygen injected from between the injection ports accelerates melting of the material to be melted, so that the melting is efficiently performed. Further, since the angle of the oxygen nozzle can be appropriately set according to the size and shape of the furnace to make the burner installation height as high as possible, it is possible to prevent the splash and blockage of the injection port by the metal. Furthermore, since a single metal block is provided with a plurality of injection ports, it is not necessary to arrange a large number of burners in the arc furnace, the equipment cost is reduced, and the handling becomes easy.

[Brief description of drawings]

FIG. 1 is a plan view of a burner.

FIG. 2 is a sectional view taken along line II-II of the burner.

FIG. 3 is a sectional view taken along line III-III of the burner.

FIG. 4 is a plan view of an arc furnace.

FIG. 5 is a partial sectional view of an arc furnace.

FIG. 6 is a diagram showing a result of an experiment regarding a dissolution efficiency of a burner.

[Explanation of Codes] 1 ... Oxygen-fuel burner for steelmaking, 2 ... Main body, 3 ... Oxygen header, 4 ... Fuel header, 8 ... Oxygen nozzle, 9 ... Fuel nozzle, 10 ... Injection port, 12 ... Second oxygen nozzle.

Claims (1)

[Scope of utility model registration request] 1. An oxygen nozzle extending obliquely downward and a fuel nozzle extending horizontally in the same vertical plane as the oxygen nozzle are arranged in one metal block so that the oxygen injected from these nozzles intersects with the fuel. A plurality of injection ports are formed, a second oxygen nozzle extending obliquely downward is provided between the injection ports, and the injection ports and the second oxygen nozzles are arranged so that the mutual intervals widen in a fan shape toward the discharge side. An oxygen-fuel burner for steelmaking, which is characterized in that