JPS5819415A - Cooling method for stave of blast furnace body - Google Patents

Abstract

PURPOSE:To cool the body of a blast furnace scrupulously in accordance with the heat load of sid body by providing plural cooling systems for the blast furnace to undergo stave cooling, providing by-pass pipes to the respective circulation lines for refrigerants and cooling the refrigerants of the desired systems. CONSTITUTION:A blast furnace 1 is segmented to a plurality in a height direction to form independent stave cooling systems C, D. By-pass pipes C2, D2 provided with coolers C3, D3 are provided to the circulating lines C1, D1 for refrigerants of the respective systems C, D. For example, in the case of using pure cold water in cooling the furnace body with the cooling system C in the shaft part, a shutoff valve C6 is closed and by-pass valves C7, C8 are opened. In the case of using pure hot water in cooling the furnace body with the cooling system D in the bost part, by-pass valves D7, D8 are closed. Thus the furnace body is cooled in accordance with its thermal load under the control of the temp. of the refrigerants by opening or closing the respective vales or regulating their openings, whereby the operations of the blast furnace are stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for cooling a blast furnace body with a staple.

Conventionally, the staple cooling of blast furnaces was initially carried out by evaporative cooling.

In evaporative cooling, the circulating power of circulating water uses the power that rises due to the light specific gravity of water containing steam.
A warm pure water cooling system with a circulation pump was installed.

After that, the cooling capacity was increased and the temperature level of the staple inside the furnace was lowered (Secondly, a cold pure water cooling system was adopted that lowered the temperature of the circulating water inside the system (-cooler) with the aim of generating ancillary materials. It's starting to look like this.

However, the cold pure water cooling system has the following problems. That is, the heat load on the blast furnace staple is not always constant, but varies over time, and there are differences in the height and circumferential directions. (:However, because the cooling is always at the same level, (1) parts that do not need to be strengthened (low heat load parts) are overcooled, and conversely, the inside of the furnace of the staple is completely cooled. This causes problems in high P operation. (2) Since seawater is constantly used for the cooler, energy is wasted.

” The present invention solves these problems and provides a method for cooling a blast furnace body with a staple, which achieves both blast furnace body protection (strengthened cooling) and blast furnace operation stability (prevention of waste disposal).

The present invention will be explained below with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of the present invention.

The present invention is the first rI! C: As shown in J, in a blast furnace of the type in which the furnace body of the blast furnace 1 is cooled by the staple
It is divided into a plurality of parts in the height direction, and an independent cooling system is installed. D and each cooling system 0. Bypass pipes C2 and D2 are provided in the refrigerant circulation paths C1 and Dl of D, and coolers 05. D5 is provided.

Coolers C3 and D3 supply seawater from pipes C4 and D4 to their respective coolers, and bypass pipes C2 and D2 within coolers C3 and D3! /It may be of the type that allows heat exchange with the flowing refrigerant. Also, refrigerant circulation route C! 1. D
2 is equipped with pumps C5 and D5, and a shutoff valve C6.
, D6, and bypass valves C7, C8, Dl, and D8. In the figure, 09 and D9 indicate a drum.

Now, the two bodies are cooled by the stay cooling system 0 formed independently on the shaft part, and the furnace body is cooled by the stay cooling system 0 formed independently in the Bosch part. If it is necessary to perform cooling with normal warm pure water, shut off valve C6 in the shaft section and open bypass valves C7 and 08, and shut off valve D in the Bosch section.
6 and close bypass valves D7 and D8.

When the valves are opened and closed in this way, the refrigerant does not pass through cooler D3 in the Bosch section, so the furnace body is cooled using warm water as a refrigerant, and in the shaft section, the refrigerant passes through cooler 05 and is cooled by seawater. For,? I? The temperature of the stave C2 decreases, and therefore the cooling of the furnace body by the stave C2 in the shaft portion can be strengthened.

Shutoff valves C6, D6, bypass valves C7, C8 according to the present invention
Assuming that Dl and D8'4 have the function of preventing backflow, by adjusting the opening degree of the shutoff valves C6 and D6,
A part of the refrigerant is cooled by cooler 2, and a refrigerant with an intermediate temperature that is a mixture of uncooled refrigerant and cooled refrigerant (it is possible to cool the furnace body from 2, and such cooling is This is effective in performing detailed cooling of the furnace body according to the heat load on the furnace body.

In the present invention, the cooling of the furnace body by the staple can be strengthened or weakened by measuring the shell temperature or the staple temperature at each part of the two blast furnaces and based on the results. This may be done based on the internal temperature measurement results, estimated values, or past blast furnace operation results.

As shown in FIG.
It can also be applied to a structure in which the blast furnace is divided into a hearth center A and a region B, which is a pool of the bosch section and the shaft section, with the blade lorepel L of the blast furnace as a boundary, and a cooling system using an independent staple is formed in each section.

Furthermore, the cooling system according to the present invention is based on MP 2.
If the furnace body is divided into a plurality of sections in the circumferential direction, for example, 2 to 8 sections, and each section is cooled independently according to the present invention, it will be extremely effective for cooling the furnace body.

FIG. 2 is a diagram showing an embodiment of the present invention, and shows the staple temperature of the shaft section, the staple temperature of the Bosch section, and the composition of hot metal when the refrigerant is switched from warm pure water to cold pure water and then from cold pure water to warm pure water. S1] is a diagram schematically showing a change in variation.

As shown in Fig. 2, when the cooling of the shaft part and the Bosch part is switched to cooling with cold pure water according to the present invention C2 at point X in the case where the tape cooling was performed using hot pure water as a refrigerant, The temperature decreases in the shaft and Bosch parts, increasing the cooling of the two bodies.

For this reason, the Bosch portion tends to be overcooled, and attached rocks are likely to form on the inner wall of the stave. Also, if the overload condition continues, the unloading inside the furnace will become unstable, and the [S1]
If the refrigerant is switched to warm pure water again at point Y, the temperature of the shaft part and the Bosch stave will rise, but C2 will remain unchanged until the temperature reaches the temperature at the first time of cooling with warm pure water. Since it takes a long time, we will investigate the cooling effect of the furnace body and the instability of unloading.
[S1] σ is also stabilized.

As described above, according to the present invention, it is possible to finely cool the furnace body of a blast furnace in which the furnace body is cooled by a stave, which is very effective in terms of blast furnace operation.

[Brief explanation of drawings]

Section 1 is a cross-sectional view showing an embodiment of the invention, and FIG. 2 is an embodiment of the invention, showing changes in the temperature of the blast furnace body and the amount of hot iron. 1; Blast furnace 2 Varnish tape 0, D; Stave cooling system C1, Dl; Refrigerant circulation path C2, D2: Bypass pipe C3, D3; Cooler C4, D4; Piping C5, D5; Pump C6, D 6
; Shutoff valve C7, D7 ;
8, D8; Bypass valve C9, D9; Drum - Fig. 2 □ Time

Claims (1)

[Claims] 1. In a blast furnace that performs staple cooling, the blast furnace is divided into a plurality of units in the height direction to form independent staple cooling systems, and a bypass pipe is provided in the refrigerant circulation path of each cooling system. A method for cooling a blast furnace body with a staple, characterized in that a cooler is provided in a bypass pipe, and the refrigerant is cooled through the bypass pipe according to the heat load on the furnace wall. 2. The method for cooling a blast furnace body with a staple according to claim 1, wherein the independent cooling system of the staple is divided in the circumferential direction of the furnace body.