JPH073315A - Top opening shaft furnace - Google Patents

Abstract

PURPOSE:To reduce the stagnation of hot air and dust in a working site and improve the working environment by positioning a suction hole of air for combustion and heating higher than an opening part for charging material to be heated. CONSTITUTION:For example, a cupola 10 arranged in a building is provided with a vertical cylindrical furnace body 12 opened at the upper part and has the charging hole 14 for charging material to be heated of pig iron, iron scrap, etc., and coke, etc. An annular wind box 26 surrounding the outside of the furnace body 12 and connected with tuyeres 24 supplies the air from a blower 28 through an air feeding pipe 30. In the blower 28, a suction pipe 32 connected with the air suction hole is erected at perpendicular upward and this opening part, i.e., the air suction hole 34 of the blower 28 is set at a higher position than the height H-H of the opening part in the charging hole 14. By this method, the blower 28 sucks the air (hot air) existing in the upper space in the building covering the cupola 10, and since this air is supplied in the furnace, the purpose can be accomplished.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaft furnace having an opening for charging a material to be heated in an upper part of a furnace body, and in particular, an upper opening type in which hot air retention is reduced at a work site to improve a working environment It concerns a shaft furnace.

[0002]

BACKGROUND ART Conventionally, a vertical furnace body has been used as a type of melting furnace, heating furnace, etc. On the other hand, there is known a shaft furnace having a structure in which air sucked from the outside by a blower or the like is supplied from the lower part of the furnace body into the furnace as combustion air or as combustion and heating gas.

In a factory equipped with such a shaft furnace, the shaft furnace tends to be housed in the building in recent years from the viewpoint of external environmental maintenance regarding noise, odor, dust, etc., and the working space is open to the outside. The degree is decreasing.
At that time, in a general factory, since the shaft furnace is the equipment with the highest ground clearance, the ceiling height of the building becomes the largest at the installation portion of the shaft furnace.

Therefore, the hot air generated in the shaft furnace and the hot air generated in other equipment such as pouring water arranged in parallel in the shaft furnace tend to gather and stay in the shaft furnace installation portion in the building, resulting in However, there is a problem that the working space around the shaft furnace becomes extremely hot and the working environment is significantly deteriorated.

Moreover, from the upper opening of the shaft furnace,
Dust such as sand adhering to the materials and sub-materials is discharged together with the hot air, so such dust also stays in the building around the shaft furnace, and it sinks and accumulates on the ground.
There was also a problem that the working environment became worse.

[0006] In recent shaft furnaces, a dust collecting port is provided below the inlet of the object to be heated, and an exhaust gas extraction system for collecting dust and the like contained in the gas reaching the upper part of the furnace is added. However, since it is common, the upper opening of the shaft furnace is not blocked, so that the exhaust gas extraction system cannot completely suppress the influence of generated hot air or dust on the work site. . Although a cooler such as a cooler is also adopted as a measure against hot air in the work space, there is a cost problem, and a sufficient environment improvement cannot be achieved by the cooler alone, and an effective system to assist it. The current situation is that there is no such thing.

[0007]

The present invention has been made in view of the above circumstances, and a problem to be solved by the present invention is to eliminate hot air from accumulating in a shaft furnace installation portion. An object is to provide an upper opening type shaft furnace capable of reducing or preventing the deterioration of the work environment due to the above.

Another object of the present invention is to provide an upper opening type shaft furnace which can reduce or prevent the deterioration of the working environment due to the dust by capturing the dust discharged from the upper opening of the shaft furnace. To do.

Further, it is an object of the present invention to provide an upper opening type shaft furnace capable of efficiently and easily achieving such an effect of improving the working environment with equipment having a simple structure. .

[0010]

In order to solve such a problem, a feature of the present invention resides in that in a shaft furnace having an opening for charging a material to be heated in an upper part of a furnace body, air for combustion or heating is provided. The suction port is located above the opening for charging the heat target.

[0011]

In the upper opening type shaft furnace having the structure according to the present invention, suction is performed through the air suction port which is located above the opening for charging the heat target of the furnace body. The generated air is guided downward and supplied as combustion air or combustion and heating gas from the lower part of the furnace body into the furnace.

As a result, the space above the shaft furnace in the building can be ventilated, and the retention of hot air can be reduced or prevented. As a result, the temperature rise in the working space around the shaft furnace can be reduced, The working environment is improved.

Further, in such an upper opening type shaft furnace, since the dust discharged from the shaft furnace is also captured together with the air by the air suction port, the air around the shaft furnace is also cleaned, The working environment is further improved.

Moreover, in the upper opening type shaft furnace according to the present invention, it can be carried out, for example, by simply extending the intake pipe of a conventionally used blower or the like upward. Since no modification or the like is required, there is an advantage that the implementation is easy and the cost is excellent.

[0015]

EXAMPLES Examples of the present invention will be described below with reference to the drawings in order to more specifically clarify the present invention.

First, FIG. 1 shows a coke cupola 10 as an embodiment of the present invention. Although not clearly shown in the drawing, the cupola 10 is installed in the building and the upper part thereof is covered with the building.

More specifically, the cupola 10 includes a vertical, substantially cylindrical furnace body 12. This furnace body 12
While being opened upward, the upper end side surface is notched in a rectangular window shape, and a charging port 14 for charging a heated object such as pig iron and iron scraps or coke into the furnace is provided.

Further, below the charging port 14, there is provided an exhaust gas extraction part 16 for collecting gas, dust, etc., which has become combustion gas in the furnace body 12 and has reached the upper part. An exhaust gas pipe 18 that guides the collected exhaust gas to a dust collector (not shown) is connected to the exhaust gas extraction unit 16.

On the other hand, at the lower end of the furnace body 12, there is provided a pool 20 for receiving the molten metal melted in the furnace, and the molten metal is discharged from the pool 20 to the outside of the furnace. A gutter 22 is attached.

Further, above the pool 20 is
A plurality of tuyere 24 is arranged to penetrate the furnace wall, and an annular wind box 26 is mounted above these tuyere 24 so as to surround the outside of the furnace body 12, It is connected to each tuyere 24.

Further, the air box 26 is connected to a blower 28 separately installed through an air supply pipe 30. Then, the air supplied from the blower 28 to the wind box 26 through the air supply pipe 30 is blown into the furnace body 12 from the tuyere 24.

Here, the blower 28 is installed on the ground in this embodiment, and the intake pipe 32 connected to the intake port thereof is erected vertically upward. The opening of the intake pipe 32, that is, the intake port 34 of the blower 28 has a height of the opening of the charging port 14 of the furnace body 12 of H−.
It is set to a position higher than H.

Although not clearly shown in the drawing, in this embodiment, a filter is arranged on the intake passage of the intake pipe 32 of the blower 28, and the intake air is removed by the filter. After that, the blower 28 is guided.

In order to carry out the pig iron melting using the cupola 10 having such a structure, as is well known, a material to be heated such as pig iron, coke or the like is charged into the furnace from the charging port 14. On the other hand, the blower 28 compresses the air sucked from the intake port 34 of the intake pipe 32, and supplies the compressed air to the wind box 26 through the air supply pipe 30. Then, the air supplied from the blower 28 to the wind box 26 is blown into the furnace through the tuyere 24 to burn the coke, thereby heating and melting the object to be heated in the furnace body 12, and the basin 20 Drop it on
The molten metal collected in the basin 20 is taken out of the furnace through the tap gutter 22. The air blown into the furnace by the blower 28 becomes combustion gas, and then is collected by the exhaust gas extraction unit 16 and discharged to the outside of the furnace through the exhaust gas pipe 18.

Since the intake port 34 of the intake pipe 32 of the blower 28 is located above the charging port 14 of the furnace body 12, the blower 28 is located in the upper space of the building covering the cupola 10. The air (hot air) present in the furnace is sucked and supplied to the furnace.

Therefore, in the cupola 10 having the above-mentioned structure, the retention of hot air in the upper space of the building can be reduced or prevented, and the ventilation efficiency of the upper space of the building can be improved. It is possible to reduce the temperature rise in the work space around the.

Further, in the cupola 10, since the dust discharged from the upper opening of the furnace body 12 is also sucked and trapped together with the air from the intake port 34, the air around the shaft furnace can be cleaned.

Moreover, in such cupola 10,
It is only necessary to extend the intake pipe 32 of the blower 28 that has been conventionally used upward, and the effect of improving the working environment as described above can be easily enjoyed without requiring any special device or major modification. It also has the great practical advantage of being able to.

Further, in such cupola 10,
It is also possible to position the intake port 34 of the intake pipe 32 of the blower 28 near the upper opening of the furnace body 12 to raise the temperature of the intake air, and thus the temperature of the air blown into the furnace. By thus increasing the temperature of the air blown into the furnace and utilizing the residual heat of the blown air, effects such as improvement of the melting efficiency, improvement of the graphite structure in high temperature melting, or increase of the molten metal temperature can be exhibited. .

Further, in this embodiment, since the filter is arranged on the intake path to the blower 28, the blower 28
Adhesion of dust to the blades, the inner surface of the air supply tube, etc. can be effectively prevented, and good maintenance and durability of the device can be secured.

Furthermore, in this embodiment, since the blower 28 is installed on the ground, a large-scale structure is not required to support the blower, and noise reduction of the blower is easy. There are advantages such as.

Incidentally, in order to confirm the effect of improving the working environment, the coke cupola was operated under the conditions shown in the following [Table 1].

[0033]

As a result, in the workplace on the second floor, where the temperature is particularly high, it is possible to lower the environmental temperature by 10 ° C or more as compared with the conventional cupola (in which the intake port of the blower is located above the ground), and ventilation is possible. Ability is 3.5 times / in the conventional cupola
What was hr was improved to 5.1 times / hr,
confirmed. Note that the ventilation capacity is the capacity of the dust collector or blower (for example, the flow velocity in the duct of the straight line section as much as possible,
It is calculated by measuring the temperature) and divided by the building volume. In addition, it is possible to reduce the capacity of the dust collector connected to the exhaust gas extraction unit 16 by the suction effect of dust or the like by the blower.
^The same level of dust collection effect achieved with a dust collector with a capacity of ³ / hr, 24% less than that, 1600
It was confirmed that it could be obtained using a dust collector with a capacity of 0 m ³ / hr. Furthermore, the temperature of the air blown into the furnace is
It was also confirmed that it is possible to raise the temperature by 30 to 40 ° C. as compared with the conventional cupola, whereby a rise in tapping temperature of 5 to 10 ° C. is achieved.

The embodiments of the present invention have been described in detail above, but these are literal examples, and the present invention should not be construed as being limited to such specific examples.

For example, in the above-described embodiment, the blower 28 is installed on the ground, and the intake pipe 32 that is long in the vertical direction is used, so that the intake port 34 becomes the inlet 1 of the furnace body 12.
It was located above 4, but the blower 28
You may install it in a high place and use a short intake pipe.

Further, the intake port 34 of the blower 28 may be located above the charging port 14, and its specific position is appropriately determined according to the structure of the cupola, the shape of the building, etc. It should be done.

Further, in the above-mentioned embodiment, one specific example of applying the present invention to the coke cupola is shown. In addition to this, solid fuel other than coke, liquid fuel such as heavy oil, and gaseous fuel such as natural gas are used. The present invention can be effectively applied to a cupola and a shaft furnace such as various melting furnaces and heating furnaces other than the cupola.

The upper opening type shaft furnace to which the present invention is applied may be any one as long as the opening for charging the object to be heated is provided in the upper part of the furnace body. The present invention can also be applied to the case where the opening is formed on the side surface of the furnace body and the flue extending above the opening is provided. Even in a shaft furnace equipped with such a flue, since hot air is discharged from the opening for charging the heated object, the air is blown above the opening for charging the heated object. It suffices that the suction port is located, and the effect of the present invention can be effectively exhibited even when the suction port is below the opening of the flue.

Although not listed one by one, the present invention is
Based on the knowledge of those skilled in the art, it can be implemented in various modified, modified, and improved modes, and
It goes without saying that all such embodiments are included in the scope of the present invention without departing from the spirit of the present invention.

[Brief description of drawings]

FIG. 1 is a front view showing a coke cupola as an embodiment of the present invention.

[Explanation of symbols]

 10 Cupola 12 Furnace Body 14 Inlet 24 Tuyere 26 Wind Box 28 Blower 30 Air Pipe 32 Intake Pipe 34 Intake Port

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Shoichi Sakai 1-2-22 Nakasaishibacho, Kakamigahara-shi, Gifu Prefecture (72) Masato Mishima 4-1-12-1 Nakasaimarketcho, Kakamigahara-shi, Gifu Sunny Heights Hana Mizuki (72) Mitsuyasu Nakajima 19-18 Sakurada-cho, Atsuta-ku, Nagoya-shi, Aichi Toho Gas Co., Ltd. (72) Kenjiro Nakajima 19-18 Sakurada-cho, Atsuta-ku, Nagoya-shi, Aichi Toho Gas Co., Ltd. (72) Inventor Tatsuya Suzuki 19-18 Sakurada-cho, Atsuta-ku, Nagoya-shi, Aichi Toho Gas Co., Ltd. (72) Inventor Takashi Tentaka 2 Kano-Sakai-cho, Gifu-shi, Gifu Prefecture

Claims (1)

[Claims] 1. A shaft furnace having an opening for charging an object to be heated in an upper part of a furnace body, wherein a suction port for air for combustion or heating is located above the opening for charging an object to be heated. An upper opening type shaft furnace characterized by being hardened.