JPH10245612A - Blasting equipment for blast furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide blasting equipment for a blast furnace which can efficiently enrich oxygen at the suction side of a blower without using an oxygen compressor, etc., and also, can stably operate by lowering the suction temp. of the blower to reduce the blasting power. SOLUTION: The blast furnace blasting equipment is constituted by arranging at least one piece of supplying nozzle 7 in the suction hole 2 of the blower 1 for blasting the air into the blast furnace 9 through a hot stove 5 or in a duct 3 at the suction side so as to supply liquid oxygen or liquid air in a tank 6 into this nozzle through a piping 6a. By this method, the temp. of the blasting air in the blower 1 is lowered, and the blasting power in the blower 1 is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blast furnace blower capable of reducing the power of a blower for blowing air to a blast furnace through a hot blast stove.

[0002]

2. Description of the Related Art In a process of manufacturing pig iron in a blast furnace, as shown in FIG. 2, air sucked from a suction port 12 of a blower 11 through a suction side duct 13 is supplied to a blower duct 14 as shown in FIG.
Is sent to a hot blast stove 15 via a blast furnace, where the temperature is raised to a predetermined temperature.
Is blown into In the above process,
In order to increase the tapping amount of the blast furnace 17, oxygen enrichment is performed in which oxygen is mixed with air blown in the process leading to the blast furnace 17. In FIG. 2, the oxygen enrichment was pressurized by an oxygen compressor 19 from an oxygen tank 18 to a blow duct 14 between the blower 11 and the hot stove 15 or to a blow duct 16 between the hot stove 15 and the blast furnace 17. In general, gas oxygen is blown through the oxygen introduction pipe 20 to perform the process.

[0003] By the way, the blowing power of the blower is obtained by a theoretical calculation formula shown by the following equation (1).

[0004]

(Equation 1)

[0005] In the above equation, since the air volume is managed in a standard state, it can be obtained by the following equation (2).

[0006]

(Equation 2)

[0007] Therefore, the variation of the value of the suction temperature T ₁ changes the result of the air volume Q _N.

Therefore, in the air blower shown in FIG. 2, the air blowing power of the blower 11 fluctuates due to the fluctuation of the atmospheric temperature, and the blowing air power is greatly increased especially in summer where the air temperature is high as compared with winter. For oxygen enrichment, blower 1
In order to introduce gaseous oxygen into the blower duct 14 or 16 located on the discharge side of the blower 1, the blower 1 is
It is necessary to make the oxygen pressure higher than the discharge pressure of the air by the method (1), and the cost of equipment and power for the oxygen compressor 19 is high.

Therefore, conventionally, in oxygen enrichment, a method of sending gaseous oxygen adjusted to a pressure lower than the discharge pressure of the blower into the blown air to the suction side of the blower for the purpose of omitting the oxygen compressor is disclosed in Japanese Patent Application Laid-Open No. H11-157572. It is disclosed in Japanese Patent Application Laid-Open No. 47-18707. Also, JP-A-6-306431 discloses that
In order to efficiently enrich oxygen by preventing oxygen drift in the configuration in which the oxygen compressor is omitted, a large number of gaseous oxygen that blow gas oxygen in a direction substantially perpendicular to the flow of the blown air are provided on both side walls of the suction duct of the blower. A device provided with a nozzle opening is disclosed.

[0010]

However, Japanese Patent Application Laid-Open No. 47-18707 and Japanese Patent Application Laid-Open No. 6-30
No. 6431 is a disclosure of a technique in which the oxygen compressor related to oxygen enrichment is omitted, and no consideration has been given to reducing the blowing power of the blower and operating it stably. In other words, simply enriching gas oxygen on the suction side of the blower does not cause a special change in the suction temperature of the blower due to gas oxygen enrichment.Therefore, in the conventional oxygen enrichment method and apparatus, the blowing power of the blower is reduced. It could not be reduced.

SUMMARY OF THE INVENTION The present invention has been made to meet the above-mentioned demand, and it is possible to efficiently enrich oxygen on the suction side of a blower without using an oxygen compressor or the like and to reduce the suction temperature of the blower. It is an object of the present invention to provide a blast furnace blower capable of reducing the blower power and stably operating the blower.

[0012]

In order to achieve the above object, the present invention provides a blower with a nozzle for blowing liquid oxygen or liquid air on the suction side. And
The temperature of the air sucked into the blower by liquid oxygen or liquid air supplied through the nozzle decreases.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION A blast furnace blower of the present invention is a blast furnace blower having a blower for blowing air to a blast furnace through a hot blast stove, wherein the suction from the air suction port or from the suction port to the suction portion of the blower is provided. At least one nozzle is provided in the middle of the side duct, and liquid oxygen or liquid air in the tank is supplied to the nozzle via a pipe.

In the above configuration, when liquid oxygen or liquid air is blown into the blown air, a latent heat component for evaporating the liquid oxygen or liquid air and a sensible heat component until the liquid oxygen or the liquid air is mixed with the air and reaches thermal equilibrium after the evaporation. Only, the temperature of the air sucked into the blower decreases. As described above, the power of the blower is reduced by reducing the suction temperature as described above.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a blast furnace blower according to the present invention will be described below with reference to FIG. FIG. 1 shows an outline of a facility arrangement around a blast furnace. 1 is a suction duct 2 from the suction port 2
Is a blower that sends air sucked in through the air blower 4 to the hot blast stove 5 through the blower duct 4. In the blast furnace blower of the present embodiment, a supply nozzle 7 for blowing liquid oxygen or liquid air supplied from a liquid oxygen or liquid air tank 6 is provided in the suction side duct 3 of the blower 1. The liquid oxygen or liquid air tank 6 is connected by a pipe 6a. In addition, in the figure, 8 is a ventilation duct that connects the hot blast stove 5 and the blast furnace 9.

For example, if the temperature of the air sucked into the blower 1 is 3
When the temperature is 0 ° C., the blowing air amount is 3917 Nm ³ / min,
The blowing pressure is 3.18 kg / cm ² and the blowing efficiency is 86%
When the blower 1 is used, the blower power in the conventional example shown in FIG. 2 is 14,761 kW as a result of dividing the value calculated from the above-described equation by the blower efficiency.

On the other hand, in the blast furnace blower having the above structure, when the atmospheric temperature is 30 ° C., the specific heat is 0.3134 kcal / Nm ³ · ° C. and the saturation temperature is -183 ° C. Has a latent heat of vaporization of 72.8 kcal / N.
When m ³ liquid oxygen is blown at 87 Nm ³ / min, by blowing the liquid oxygen, the latent heat for vaporization and the suction temperature are reduced by the amount of sensible heat mixed with air to reach thermal equilibrium. The suction temperature of the blower 1 became 20 ° C. When the suction temperature is 20 ° C.,
The power for blowing 004 Nm ³ / min was 14,600 kW as a result of calculation in the same manner as described above.

As described above, by blowing the liquid oxygen into the suction side duct 3 of the blower 1, when the blower 1 sucks, the atmospheric temperature of 30 ° C. is reduced to 20 ° C., and when the suction temperature is 20 ° C. As compared with the conventional example, the blowing power of the blower 1 was able to reduce the blowing power by about 160 kW despite the increased flow rate by blowing oxygen. Furthermore, in the case of the blast furnace blower having the above configuration, the oxygen compressor provided for blowing oxygen into the blower discharge side can be omitted.

The inventor of the present invention has set the blower 1 having the above-mentioned setting.
In the case where the above liquid oxygen is blown (this embodiment),
The yearly comparison was made with the case (conventional example) not so. The following table is partially shown in April (spring), August (summer), 1
The results for January (autumn) and January (winter) are shown.

[0020]

[Table 1]

As described above, by injecting liquid oxygen, in this embodiment, the atmospheric suction temperature is decreased by about 10 ° C. on average with respect to the conventional example, whereby the average is about 160 ° C./month.
A power reduction of 5 kW was achieved, and as a result, although not shown in the table, a power reduction of 1200 MWh could be realized annually. Especially in summer, liquid oxygen (or liquid air)
By adjusting the amount of enrichment, there is no power difference from winter, and stable operation can be performed throughout the year.

In the above embodiment, liquid oxygen is blown. However, if liquid air is blown from the supply nozzle 7 through the pipe 6a using the liquid oxygen tank 6 as a liquid air tank, the flow rate of the blower 1 increases. As a result, only the temperature of the blower 1 is reduced, so that the blowing power can be further reduced. Further, in the blast furnace blower of the present invention, the position of the liquid oxygen or liquid air blowing,
There is no particular limitation as long as it is between the suction port 2 of the blower 1 and the blower 3, but the number, arrangement, and blowing performance of the supply nozzles 7 are such that the oxygen concentration distribution after blowing is uniform in the blowing air. Should be considered. Furthermore, since the blast furnace blower of the present invention does not require a special configuration for controlling the blower 1 itself, it is easy to implement.

[0023]

As described above, the blast furnace blower of the present invention
Since liquid oxygen or liquid air is blown into the suction side of the blower, the suction temperature of the blower is reduced, so that the blowing power can be reduced. Can operate. Further, in the blast furnace blower of the present invention, the point where the liquid oxygen or liquid air is blown is on the suction side of the blower, so that the oxygen compressor required for oxygen enrichment can be omitted, and cost reduction can be achieved. Can contribute to.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing an arrangement of facilities around a blast furnace employing a blast furnace blower of the present invention.

FIG. 2 is a view schematically showing an arrangement of equipment around a blast furnace according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Blower 2 Suction port 3 Suction side duct 5 Hot blast stove 6 Liquid oxygen (or liquid air) tank 6a piping 7 Supply nozzle 9 Blast furnace

Claims (1)

[Claims] In a blast furnace blower having a blower for blowing air to a blast furnace through a hot blast furnace, at least one nozzle is provided in the middle of an air suction port or a suction side duct from the suction port to a suction portion of the blower. A blast furnace blower, wherein liquid oxygen or liquid air in a tank is supplied to the nozzle via a pipe.