JP2560387Y2 - Burner for powder injection into blast furnace - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a burner used for blowing powder fuel from a tuyere into a blast furnace.

[0002]

2. Description of the Related Art In a blast furnace operation, injecting pulverized coal from a tuyere can reduce pig iron cost and coke, which is the main fuel of the blast furnace, and consequently reduce the amount of coke produced. This is a very important technology that will also extend the life of the reactor.

However, pulverized fuel such as pulverized coal has the disadvantage that it has a slower burning rate than heavy oil and contains unburned components such as ash, so that various measures must be taken when injecting. . Speaking of ash, the ash in pulverized coal is melted by the heat of combustion, but this melt adheres and accumulates at the tip of the pulverized coal blowing burner, narrowing the pulverized coal feed path. It becomes difficult to maintain stable blowing, and eventually it is also difficult to maintain a stable furnace condition. Therefore, prevention of ash adhesion is an important issue in the pulverized coal blowing operation.

[0004]

However, since the conventional pulverized coal injection burner only blows out the cooling medium from the outer peripheral portion of the tip of the pulverized coal feed path, depending on the type of pulverized coal, As shown in FIG. 2, there is a problem that the ash 2 adheres to the outer peripheral portion of the tip portion of the burner 1 for pulverized coal injection.
The removal of the ash 2 is a very troublesome operation of hitting the base end of the burner 1 during operation. Note that FIG.
Reference numeral 3 denotes a blow pipe, and reference numeral 4 denotes a blast furnace tuyere.

An object of the present invention is to solve the problems of the conventional burner and to provide a burner for blowing powder into a blast furnace, which can effectively prevent ash adhering to the tip of the burner. .

[0006]

In order to achieve the above object, a powder burner for blowing powder into a blast furnace according to the present invention is inserted into a blow pipe for blowing hot air connected to a tuyere of a blast furnace. In a powder injection burner provided so that the tip portion penetrates through the outer peripheral wall, an inner cylinder serving as a powder supply path for guiding a solid-gas two-phase flow, and cooling is performed on an outer peripheral portion of the inner cylinder. In addition to the double cylinder configuration with the outer cylinder forming the medium passage, a cooling medium ejection hole is provided in the distal end wall and the outer peripheral wall of the distal end of the outer cylinder.

[0007]

In the burner for blowing powder into a blast furnace according to the present invention, a cooling medium ejection hole is provided also at a tip outer peripheral wall of an outer cylinder forming a cooling medium passage with an outer peripheral wall of an inner cylinder. Conventionally, the ash attached and deposited on the tip of the burner can be blown off by the cooling medium ejected from the ejection hole.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a burner for blowing powder into a blast furnace according to the present invention will be described with reference to an embodiment shown in FIG. FIG. 1 is a partial cross-sectional view of one embodiment of a tip portion, which is a main part of a burner for blowing powder into a blast furnace according to the present invention.

In FIG. 1, reference numeral 11 denotes an inner cylinder formed by a powder supply path 12 for guiding a solid-gas two-phase flow of a carrier gas such as N ₂ or air and, for example, pulverized coal. Is provided with an outer tube 14 so as to form an annular space defined by the outer peripheral surface of the inner tube 11 and the cooling medium passage 13.

[0010] 15 is a coolant jetting holes for jetting N ₂ or air or the like provided suitable number to the front end wall portion 14a of the outer cylinder 14, the shape is oval, appropriate shape of a circular shape, or the like Is fine. The hole may be straight as shown in FIG. 1 or may be tapered so that the cooling medium faces inward or outward.

Numeral 16 denotes cooling medium ejection holes provided at an appropriate number on the outer peripheral wall portion 14b at the distal end portion of the outer cylinder 14, where ash is likely to adhere.
Similarly to the above, the shape may be an appropriate shape such as a circle or an ellipse. The hole may be straight as shown in FIG. 1 or may be tapered so that the cooling medium is directed forward or backward, as described above.

In this embodiment, the cooling medium ejection holes 15
Although 16 has been disclosed as being arranged in a row in the same diameter or at the same distance from the tip, it may be provided in a staggered manner or in a plurality of rows.

In order to confirm the effect of the burner for blowing powder according to the present invention, the burner having the structure shown in FIG.
was used as the pulverized coal blown burner in blast furnace m ^3, in the conventional burner having no cooling medium injection hole, adhering ash of pulverized coal to the distal portion, it is taken measures such as tapping the base end portion of the burner Even with the coal type that had to be used, the use of the burner of the present invention enabled stable pulverized coal injection to be continued without taking any measures.

[0014]

As described above, the powder burner for blowing powder into the blast furnace according to the present invention also cools the outer peripheral wall of the outer cylinder, which forms the cooling medium passage with the outer peripheral wall of the inner cylinder. Since the medium ejection hole is provided, the ash which has conventionally adhered to and deposited at the tip of the burner can be blown off by the cooling medium ejected from the ejection hole, and therefore, the pulverized coal can be stably stably without taking any measures. Can be continued. That is, by using the burner of the present invention, labor saving of the blast furnace operation and stable maintenance of the blast furnace condition can be achieved.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of an embodiment of a tip portion, which is a main part of a burner for blowing powder into a blast furnace according to the present invention.

FIG. 2 is an explanatory diagram of a problem of a conventional burner for pulverized coal injection.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Inner cylinder 12 Powder supply path 13 Cooling medium passage 14 Outer cylinder 15, 16 Cooling medium ejection hole

Claims (1)

(57) [Scope of request for utility model registration] 1. A powder-injection burner, which is provided so as to penetrate an outer peripheral wall of the blowpipe into a hot-air blowpipe connected to a tuyere of a blast furnace, so that a tip end of the blowpipe is blown by a solid-air gas burner. A double cylinder comprising an inner cylinder forming a powder supply path for guiding a phase flow and an outer cylinder forming a cooling medium passage on the outer periphery of the inner cylinder, and a tip wall portion and a tip portion of the outer cylinder A burner for blowing powder into a blast furnace, wherein a cooling medium ejection hole is provided in an outer peripheral wall portion.