JP3179263B2 - Coke production method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing blast furnace coke. More specifically, increase productivity,
The present invention relates to the production of coke for blast furnaces that reduces the amount of fuel used.

[0002]

2. Description of the Related Art Conventionally, in Japanese Unexamined Patent Publication (Kokai) No. 2-194087, the flue temperature is set in the range of 1150 ° C. to 1350 ° C., and the coke temperature
When the temperature reaches within the range of 0 to 900 ° C, the furnace is discharged and C
Immediately after the coke is charged into the DQ, air is introduced into the pre-chamber of the CDQ, and the gas mainly generated from the coke is burned in the pre-chamber, so that the temperature is at least 700 ° C. or higher. A method characterized by heating and firing coke has been proposed. The quality of the coke discharged at low temperature is determined by CDQ.
By performing heating and baking in the pre-chamber, the same physicochemical properties as those of the prior art are guaranteed.

[0003]

SUMMARY OF THE INVENTION Japanese Patent Laid-Open No. 19408/1990
In the low-temperature kiln release technology disclosed in Japanese Patent Publication No. 7, since the carbonization temperature is low,
Coke shrinkage is small, and after completion of carbonization, an increase in extrusion resistance of produced coke becomes a problem. Usually, the coke temperature at the center of the coking chamber is 7
Dry distillation must be performed until the temperature reaches 00-900 ° C. It takes 18 hours or more for the coke temperature in the center of the carbonization chamber to reach 700 to 800 ° C., and such a method alone has advantages in productivity and energy consumption as compared with the conventional method. There are few.

An object of the present invention is to provide a method of manufacturing coke for a blast furnace, which can solve the problems in the prior art as described above. That is, an object of the present invention is to provide a method of manufacturing blast furnace coke which can achieve an improvement in productivity and an improvement in energy saving.

[0005]

The above objects can be attained by blowing air or oxygen from a furnace lid and firing coke at the furnace end before the completion of carbonization. That is, the present invention uses a dry distillation furnace, after carbonizing the coke temperature in the center of the furnace in the furnace width direction to 500 to 700 ° C. at the furnace end, and then blowing air to thereby form a gas between the coke and the generated gas from the coke. The combustion reaction proceeds, and the coke at the furnace end is fired. According to the present invention, the coke temperature at the end of carbonization can be reduced, and the extrusion resistance can be reduced.

[0006]

When the coke temperature is low at the end of the carbonization, the coke does not shrink sufficiently and the gap between the furnace wall and the coke is not secured, so that the extrusion resistance increases. For this reason,
In the method disclosed in JP-A-194087, the lower limit value of the coke temperature at the center of the carbonization chamber at the end of dry distillation is 700 to
Requires 800 ° C. The present inventor believes that the main cause of the extrusion resistance is a delay in coke carbonization of a portion (hereinafter, also referred to as a furnace end) within 1 to 2 m from both the furnace lid (1) and the CS lid (2). I found something. At the end of carbonization, the coke temperature is 200 to 300 at the furnace end compared to the furnace center.
℃ lower, the coke at the furnace end is the main cause of extrusion resistance.

In the present invention, the coke temperature at the center in the furnace width direction at the furnace end is carbonized to 500 to 700 ° C. in the carbonization furnace. The central part of the coke oven in the width direction is calcined in the part, so that the extrusion resistance can be reduced. The blowing of air or oxygen is performed uniformly in the longitudinal direction of the furnace lid, but may be performed only from the lower part of the furnace.

[0008] As for the blowing conditions of air, the blowing flow rate is 4 to 6 Nm ³ / min, and the blowing air temperature is raised at room temperature or by preheating. As the oxygen blowing conditions, the blowing flow rate is 0.8 to 1.3 Nm ³ / min, and the temperature of the blown oxygen is raised at room temperature or by preheating.
Unless the coke temperature at the center of the furnace at the furnace width direction is heated up to at least 500 ° C., the coal is softened and not re-solidified, so there is no crack in the center and air cannot be blown into the carbonization chamber. . In order to shorten the carbonization time, it is more advantageous to set the maximum temperature to 700 ° C. or less.

According to the present invention, the coke temperature at the end of carbonization can be reduced to 500 ° C. For example, when carbonization is performed to a coke temperature of 800 ° C. at a furnace width of 450 mm in a carbonization furnace, a carbonization time of 17 hours is required. One hour can be saved in 16 hours. Further, by this, the total energy consumption can be reduced by 6% as compared with the case of starting the furnace at 800 ° C. The furnace end coke temperature must be at least 700 ° C. to keep the extrusion resistance within allowable operating limits. The rate of temperature rise of the furnace end by blowing air or oxygen is 100
It rapidly decreases at 0 to 1100 ° C. For the above reasons, the upper and lower limits of coke at the furnace end after blowing air or oxygen are 7
00 to 1100 ° C. The coke oven used in the present invention is not limited to a room coke oven, and a vertical oven may be used.

[0010]

FIG. 1 shows an embodiment of the present invention. Furnace width 450
mm, a furnace length of 15.7 m and a furnace height of 6.5 m, the carbonization was carried out at a flow temperature of 1100 ° C. until the coke temperature in the center of the furnace width became 880 ° C., and the carbonization time was 1
It took 8 hours (Comparative Example). When the coke temperature in the furnace width direction center coke temperature in the area within 1 to 2 m from both the PS furnace lid (1) and the CS furnace lid (2) is 500 ° C., the carbonization time is 16 hours and 2 hours. Was reduced (Example of the present invention).

The coke temperature at the center in the furnace width direction is 880.
The extrusion current of the extruder at ℃ (the coke temperature at the furnace end was 730 ° C) was 187A at the maximum. On the other hand, after the coke temperature of the center of the furnace at the furnace end in the furnace width direction was carbonized to 500 ° C., the PS furnace lid (1) and the CS furnace lid (2) were moved from the furnace bottom to the center in the furnace width direction and from the furnace bottom in the furnace height direction, respectively. .5m, 2.
The air blowing flow rate is 4.8 Nm ³ through an air blowing hole (3) having an inner diameter of 100 mm installed at a position of 5 m or 4.5 m.
/ Min by blowing air for 10 minutes,
The temperature at the center of the coke in the furnace width direction up to 2 m from the S and CS furnace ends rose to 1000 ° C., and after this firing, the extrusion current of the extruder reached 150 A at maximum, and was within the allowable range of the extrusion current. The coke properties were DI = 8
4.5, CSR = 58.0 secured. According to the example of the present invention, the carbonization time can be reduced by 2 hours, and the total energy consumption can be reduced by 11%.

[0012]

As described above, according to the present invention, air is blown from the furnace lid before firing and the coke is baked, so that the carbonization time is 2 times shorter than that of dry distillation up to the coke temperature of 880 ° C. in the center in the furnace width direction. It achieves a reduction in time and energy consumption of about 11%, and is promising as a method for producing blast furnace coke.

[Brief description of the drawings]

FIG. 1 is a schematic side view of one embodiment of the present invention.

[Explanation of symbols]

 1 Extruder side (PS) furnace lid 2 Coke side (CS) furnace lid 3 Air blow hole

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-112686 (JP, A) JP-A-2-194087 (JP, A) JP-A-3-296597 (JP, A) JP-A 7-112 90278 (JP, A) JP-A-7-113079 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C10B 57/00 C10B 57/02 C10B 57/14 C10B 25/06

Claims (1)

(57) [Claims] 1. A coke oven comprising a PS furnace lid (1) and a CS
After the coke in the center of the furnace width direction within a range of 1 to 2 m from both furnace lids of the furnace lid (2) is carbonized to a temperature of 500 to 700 ° C., the PS furnace lid (1) and the CS furnace lid (2) A method for producing coke, characterized in that the coke is fired to 700 to 1100 ° C by blowing air or oxygen from a pipe of a lid.