JP2007016257A - Structure for furnace wall of blast furnace - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make mitigation of a heat stress acted on the lower end surface of a copper stave, in the case of being a constitution arranging the copper stave on refractory bricks supporting a cooling table. <P>SOLUTION: The refractory brick 5 for supporting the cooling table 6 and the copper stave 3 arranged on the upper surface of the refractory brick 5, are arranged and the lower end part of the copper stave 3 is set far back to about 100-300 [mm] to the surface on the inside of a furnace at the most upper part of the refractory brick 5 to form a step part 10 on the most upper surface of the refractory brick 5. In this way, according to a blast furnace operation, the stuck material 11 functioned as the heat insulating wall on the step part 10, can be piled up and stuck, and the heat stress acted on the lower end surface of the copper stave 3 can be mitigated. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a blast furnace wall structure for producing pig iron.

  The blast furnace body has profiles such as morning glory above the tuyere (Bosch), furnace belly (berry), and hearth (shaft). This profile is determined empirically according to the movement of the solid, liquid and gas in the furnace. For example, the furnace chest angle and the morning glory angle are determined in consideration of the charge in the lower part of the furnace, the increase in volume due to the gas temperature increase, and the like. In such a blast furnace body, for example, Patent Document 1 proposes a blast furnace wall structure in which a furnace wall upper part is cooled by a stave method and a furnace wall lower part is cooled by a cooling disk method.

JP-A-8-199211

  However, as shown in FIG. 3, when the stave 103 is arranged on the refractory brick 102 that supports the cooling plate 101, the lower end surface of the stave 103 is adjacent to the refractory brick 102, so that the lower end surface is heated. It becomes easy to receive stress. As a result, the lower end surface of the stave 103 is repeatedly subjected to thermal stress, and particularly when there is a welded portion on the lower end surface of the stave 103, the welded portion may be damaged and water leakage may occur.

  The present invention has been made in view of the above points, and in the case where the stave is arranged on the refractory brick that supports the cooling plate, the thermal stress acting on the lower end surface of the stave can be alleviated. The purpose is to.

  A blast furnace wall structure according to the present invention includes a support body that supports a cooling plate, and a copper stave disposed on an upper surface of the support body, and a lower end portion of the copper stave is located inside the uppermost furnace of the support body. It is characterized in that a step portion is formed on the uppermost surface of the support body with a depth of about 100 to 300 [mm] with respect to the surface.

  According to the present invention, the lower end portion of the copper stave is recessed about 100 to 300 [mm] with respect to the uppermost furnace inner surface of the support so that a stepped portion is formed on the uppermost surface of the support. Therefore, the deposit functioning as a heat insulating wall can be deposited on the stepped portion, and the thermal stress acting on the lower end surface of the copper stave can be reduced.

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a diagram showing a portion from the tuyere to the morning glory of the blast furnace furnace wall structure of the present embodiment. In the upper area of the morning glory, a copper stave 3 is installed inside the iron skin 1 via a castable 2. The copper stave 3 has an appropriate angle that increases in diameter as it goes upward. The copper stave 3 has a strip-like brick portion 3a on the inner surface of the furnace, and is cooled by cooling water flowing from a cooling water supply device (not shown) provided outside the iron shell 1.

  In FIG. 2, the internal structural example of the copper stave 3 is shown. As shown in the figure, a cooling water channel 3b is formed inside the copper stave 3. In that case, openings are formed on the upper and lower end surfaces of the copper stave 3 in order to perform drilling from the upper and lower end surfaces of the copper stave 3. The Therefore, the plug 3c is fitted into these openings and is welded (welded portion 3d). Thus, when there exists the welding part 3d in the lower end surface of the copper stave 3, when the lower end surface receives a thermal stress repeatedly, there exists a possibility that the welding part 3d may be damaged especially.

  Returning to FIG. 1, refractory bricks 5 are stacked inside the iron shell 1 as a support for the cooling panel 6 in the lower region of the morning glory above the tuyere 4. The furnace inner surface of the refractory brick 5 has an appropriate angle that increases in diameter as it goes upward, that is, from the tuyere 4 side toward the copper stave 3 side.

  Furthermore, in the lower region of the morning glory above the tuyere 4, support portions 7 for supporting the cooling board 6 are arranged in a staggered manner. The support part 7 is a hole penetrating from the iron skin 1 to the furnace inner surface of the refractory brick 5, and the cooling panel 6 can be inserted into each support part 7 from the outside of the iron skin 1. That is, the cooling boards 6 are arranged in about 4 to 5 stages (4 stages in the illustrated example) at appropriate intervals (preferably at equal intervals) in the circumferential direction of the blast furnace.

  Between the copper stave 3 and the castable 2 and the refractory brick 5, an irregular refractory 9 for absorbing expansion of the refractory brick 5 and the like is provided.

  Here, as shown in FIG. 1, the angle of the copper stave 3 is made to stand up to the angle of the furnace inner surface of the refractory brick 5, and the lower end of the copper stave 3 is placed on the furnace inner surface of the uppermost refractory brick 5. On the other hand, the depth is about h = 100 to 300 [mm] (positioned in the direction outside the furnace). Therefore, the step portion 10 is formed on the uppermost surface of the refractory brick 5.

  In the blast furnace structure described above, the lower end of the copper stave 3 is recessed about 100 to 300 [mm] with respect to the furnace inner surface of the uppermost refractory brick 5, and the step is formed on the uppermost surface of the refractory brick 5. Since the portion 10 is formed, the deposit 11 (thermal conductivity of 1 to 2 W / m · ° C.) can be deposited on the step portion 10 along with the operation of the blast furnace. And since this deposit | attachment 11 functions as a heat insulation wall, the thermal stress which acts on the lower end surface of the copper stave 3 can be relieve | moderated, and the welding part 3d of the lower end surface of the copper stave 3 can be protected from a thermal stress.

  In this case, the width of the stepped portion 10 is set to 100 to 300 [mm]. If the width is less than 100 [mm], the thickness of the deposit 11 becomes thin, and a sufficient heat insulating effect cannot be obtained. This is because the thermal stress acting on the lower end surface of the copper stave 3 cannot be sufficiently relaxed. Further, if it exceeds 300 [mm], the step at the boundary between the profile formed by the cooling plate 6 and the refractory brick 5 and the profile formed by the copper stave 3 becomes too large, and the charge is stable. This is because the descent may be hindered.

  In addition, since the upper end surface of the copper stave 3 is strongly cooled adjacent to another copper stave, the thermal stress is small and there is no possibility that the welded portion 3d is damaged.

  As mentioned above, although this invention was demonstrated with various embodiment, this invention is not limited only to these embodiment, A change etc. are possible within the scope of the present invention.

It is a partial sectional view of the blast furnace structure of this embodiment. It is a figure which shows the internal structure of a copper stave. It is a figure for demonstrating the case where the surface of a copper stave and the furnace inner surface of a refractory brick are made flush.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Iron skin 2 Castable 3 Copper stave 4 Tuyere 5 Fireproof brick 6 Cooling board 7 Support part 9 Indeterminate refractory 10 Step part 11 Deposit

Claims (2)

A support that supports the cooling plate;
A copper stave disposed on the upper surface of the support,
The lower end of the copper stave is recessed about 100 to 300 [mm] with respect to the furnace inner surface of the uppermost part of the support, and a step is formed on the uppermost surface of the support. Blast furnace wall structure.   The blast furnace wall structure according to claim 1, wherein a profile of a lower region of morning glory is formed by the cooling plate, and a profile of an upper region of morning glory is formed by the copper stave.

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