JPH11228971A - Method for operating coke oven - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the load on a coke oven wall in coke pushing in order to extend the life of a coke oven and to reduce the pushing resistance in order to achieve stable operation. SOLUTION: This method is characterized in that a coal blend is mixed with 0.5-10 wt.% lump coke having a lump size of 40-200 mm and the resultant mixture is charged into a coke oven, then carbonized, and pushed out or in that a coal blend to be charged into a coke oven through a charging port at the side of a pusher is mixed with 0.5-10 wt.% lump coke having a lump size of 40-200 mm and the resultant mixture is carbonized and pushed out.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for operating a coke oven.

[0002]

2. Description of the Related Art In the operation of a coke oven, when the coke is discharged from the oven (when the coke is extruded by the extruder), the load current value of the extruder is monitored to control the extrudability. . If the load current value of the extruder increases and the extrusion load increases, the force acting on the furnace wall of the coke oven also increases, and if such a high load is repeated in the long term, there is a risk that the furnace wall may be damaged. Have been. Damage to the furnace wall will not only severely hinder production, but also increase the cost of coke production due to the enormous repair costs. In some cases, coke may be stuck in the furnace during extrusion and may not move at all. This phenomenon is called a blockage and is one of the serious troubles that occur during the operation of the coke oven. If this clogging occurs, not only will the coke oven wall be damaged, but also the coke production as a furnace group will be reduced due to interruptions in operations and changes in the charging schedule, and the coke oven will be placed until it can be extruded. As the time increases, the amount of heat consumed also increases, leading to an increase in coke production costs.

[0003] As a method of reducing the extrusion resistance and avoiding the clogging, for example, the shrinkability of the coal blend after dry distillation re-solidification is determined by measuring the coalification degree parameter of the coal blend, the elapsed time after re-solidification, and the charging time. (Japanese Unexamined Patent Publication (Kokai) No. 3-273091), by measuring the burnout in the vertical or horizontal direction in advance using a test coke oven, (Japanese Patent Application Laid-Open No. 5-339580) and a method for controlling the secondary shrinkage obtained from the measurement of the coke bed height during carbonization in a practical operation to a predetermined value or more (Japanese Patent Application Laid-Open No. 6-339580).
271865), the relationship between the blending of coal and the secondary vertical burn-out rate was previously determined using a test furnace, and the relationship between the secondary vertical burn-out rate and the required extrusion pressure during coke cake extrusion in a room-type coke oven. And adjusting the blending of the coal charged into the coke oven so that the required extrusion pressure is equal to or less than the control value (JP-A-8-283732).
JP-A-6-27185), or an extrusion method for reducing the extrusion resistance by pushing the furnace wall side from a position 1/4 of the width of the carbonization chamber from the furnace wall of the coke cake (JP-A-6-27185).
No. 7) is known.

[0004] In order to realize the above method, it is essential to restrict the type of coal and the operating conditions of the blended coal. However, as the coke oven is aged, there is a need for prevention of clogging and reduction of extrusion resistance. In the current situation of ever-increasing levels, there is a need for a method for drastically reducing extrusion resistance in order to achieve energy-saving and low-cost production.

[0005]

SUMMARY OF THE INVENTION The present invention significantly reduces the load on the coke oven wall when coke is discharged from the coke oven, prevents damage to the coke oven wall, and reduces the cost of repairing the coke oven wall. It is another object of the present invention to provide a method of operating a coke oven, which extends the life of the coke oven and prevents a clogging, thereby enabling a stable operation without a production obstacle.

[0006]

According to the present invention, in order to solve the above-mentioned problems, 0.5 to 10% by weight of lump coke having a particle size of 40 to 200 mm is mixed into a blended coal and charged into a coke oven. After that, it is characterized by extruding, and the particle size of the blended coal charged from the inlet of the extruder is 40 to 200 mm.
Of 0.5 to 10% by weight of coke, and after carbonization,
This is a method of operating a coke oven characterized by extruding.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The present inventor has invented a method of increasing horizontal burnout by reducing the gap at the center of the coking chamber after the coal in the center of the coking oven has been re-solidified. It is known that horizontal burnout defined by the gap between the coke oven wall 4 and the surface of the coke cake 1 starts to occur after the coal in the center of the coke oven carbonization chamber is re-solidified. Sponge coke is formed in the central part of the coke oven carbonization chamber, and the coke cake 1 is usually not connected. The coke cake in the coking chamber shrinks toward the center of shrinkage, resulting in a gap near the furnace wall and a gap in the center of the coking chamber (FIG. 1). The gap width in the vicinity of the furnace wall and the gap width in the central part of the carbonization chamber differ depending on where the shrinkage center is, but a gap of approximately the same width is formed in the vicinity of the furnace wall and in the center. As described above, if the center of contraction of the coke cake can be set at the center of the carbonization chamber, the gap at the center of the carbonization chamber can be reduced, and the gap near the furnace wall (horizontal burning reduction) can be increased. The present invention has been completed based on these findings.

Hereinafter, the present invention will be described specifically. When the lump coke 2 is not mixed, the coke cakes 1 on both sides shrink independently toward their respective shrinking centers, so that a gap is generated at the center of the coking chamber (FIG. 1). On the other hand, when lump coke 2 is mixed with blended charcoal, lump coke is incorporated into the coke cake structure when the blended coal is coked to form coke cake 1, and is integrated at the center of the coking chamber on both walls. Of coke cake. As a result, the movement of the coke cake 1 on both walls is constrained by the lump coke 2, and the coke cake on both walls shrinks around the connection part of the lump coke, that is, the vicinity of the center of the carbonization chamber as a contraction center. The gap at the center is reduced (FIG. 2). Since the total shrinkage of the coke cake is substantially constant depending on the operating conditions, the gap near the furnace wall (horizontal burning reduction) increases as the gap at the center of the coking chamber decreases. It is known that the greater the horizontal burnout, the lower the extrusion resistance, and the above method can reduce the extrusion resistance.

Regarding the mixing ratio of the lump coke 2, the upper limit of 10% by weight is determined by the maximum mixing ratio which does not lower the coke strength. In some cases, it may be necessary to adjust the coal mix to maintain coke quality. The lower limit of 0.5% by weight is the minimum amount required to provide the effect of increasing burnout. Further, the size of the lump coke to be mixed is determined by the minimum value of 40 mm, which is the lower limit, from the minimum size required to connect the coke lump on both sides in the center of the coking chamber. The upper limit of 200 mm is the maximum particle size of the lump coke produced in the actual furnace.

In the coke oven, the pushing load is maximized when the coke cake in the coke oven coking chamber starts to move. At this time, the coke cake 1 on the extruder 5 side is compressed and the coke cake wall 4 is pressed. Is transmitted. Therefore, as shown in FIG. 3, by mixing lump coke only in the blended coal charged from the charging port 9 on the extruder side, the horizontal burnout of the coke near the extruder-side furnace lid is increased. It is also possible to reduce extrusion resistance during coke extrusion.

[0011]

Example 1 In an actual furnace with a furnace height of 6 m, (1) when lump coke is not blended,
(2) When 3% by weight of lump coke is blended in all blended coal,
(3) The difference in extrusion resistance was compared when 5% by weight of lump coke was blended into the blended coal charged from the loading port on the extruder side. Furnace height 1m, furnace length 1m, furnace width 42
In a 5 mm test coke oven, horizontal burnout and extrusion resistance were measured for (1) non-blended coke and (2) 3 wt% of lump coke blended in all blended coal. Lump coke having an average particle size of 80 mm was used.
As shown in FIG. 4, in the test furnace, it can be seen that the horizontal burnout increases due to the lump coke blending and the extrusion resistance decreases. Further, in the actual furnace, the lump coke can be mixed into all the blended coal, or the lump coke can be blended into the blended coal charged from the charging port 9 on the extruder side, whereby the extrusion resistance can be reduced. Was.

[0012]

According to the present invention, the load acting on the coke oven wall when the coke is discharged from the coke oven can be remarkably reduced, and the clogging can be prevented. This enables stable operation,
The cost of repairing the furnace wall and extending the life of the furnace can be achieved by avoiding furnace wall damage due to blockage, and the economic effect is large.

[Brief description of the drawings]

FIG. 1 is a view showing that a gap (horizontal burnout) near a furnace wall and a gap in a central portion of a carbonization chamber exist when the present invention is not implemented.

FIG. 2 is a diagram showing that horizontal burnout is increased by the present invention.

FIG. 3 is a diagram showing a method of mixing lump coke only in blended coal charged from a charging inlet on an extruder side in the present invention.

FIG. 4 is a diagram showing that horizontal burnout increases and extrusion resistance decreases according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Coke cake 2 Lump coke 3 Coke oven carbonization room 4 Furnace wall 5 Extruder 6 Charging hopper 7 Normal charging 8 Lump coke mixed charging 9 Charging inlet

Claims (2)

[Claims] 1. A method for operating a coke oven, characterized in that lump coke having a particle size of 40 to 200 mm is mixed with blended coal in an amount of 0.5 to 10% by weight, charged into a coke oven, extruded after carbonization, and extruded. 2. Mixing coke having a particle size of 40 to 200 mm with a coke of 0.5 to 10 to a blended coal charged from a charging inlet on an extruder side.
A method of operating a coke oven, comprising mixing by weight, extruding after carbonization.