JP3335661B2 - Operating method of coke oven - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the operation of a coke oven in which coking coal different in the furnace width direction in a coke oven carbonization chamber is charged to reduce the expansion pressure acting on the actual furnace wall without deteriorating the coke strength. About the method.

[0002]

2. Description of the Related Art When a coal is carbonized in a carbonization chamber of a coke oven, the pressure acting on the furnace wall of the coke oven due to the expansion of the coal is generally referred to as the expansion pressure of the coal. For example, U.S.A. S. Steel Fairf
Like the No. 2 coke oven at the Field Steel Works, the wall of the coke oven is damaged and becomes inoperable (JF McDerm).
ott et al. , Iron & Steel M
aker, 13 (1986), 51), and the expansion pressure management is an important issue in furnace body management.

[0003] In Japan as well, in the future the aging of the furnace body will progress and the strength of the furnace body will decrease, while the introduction of coal pretreatment techniques such as the humidified coal method will increase the coal charging density in the coking chamber. The expansion pressure tends to increase, and there is a concern that the furnace body may be damaged by the expansion pressure. In addition, the coal expansion is considered to be high even from the viewpoint of the raw material, and the degree of coalification is high (the volatile matter content is low)
There is a tendency for the blending ratio of coal to increase, and it is becoming necessary to pay attention to the expansion pressure.

[0004] As a method of reducing the expansion pressure, a method of reducing the coal particle size of the blended coal or adding an inert component such as coke breeze is known. However, when the particle size of the coal is reduced, the charging density is lowered, and the productivity is lowered. In addition, there are problems such as increased dust generation during handling, and this is not a practical method for reducing the expansion pressure. On the other hand, when an inert component is added, there is a problem that the coke strength is significantly reduced.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a coking coal different in the width direction of a coking chamber of a coke oven furnace is charged, and an inert substance is contained in the coking coal charged into the center of the coking chamber. Suppress the expansion pressure without impairing coke strength by using blended coal, blended coal with a high volatile content and a large amount of inactive components in the coal microstructure component, blended coal with small particle size, or blended coal with low cohesion An object of the present invention is to provide a method of operating a coke oven.

[0006]

SUMMARY OF THE INVENTION According to the present invention, when raw coal is charged into a coke oven and dry-distilled, coke breeze, anthracite, semi-anthracite, semi-coke,
A blended coal containing poorly caking coal, such as petroleum coke, is charged, or at the center of the furnace in the furnace width direction, the volatile content is higher than that of a blended coal charged on the wall side. the amount of active ingredient is large coal blend, small coal blend having compared particle size in coal blend to be charged into the wall, also compared to the coal blend to be charged into the wall,
A method of operating a coke oven characterized by charging a coal blend with low cohesion.

[0007]

Hereinafter, the present invention will be described in detail together with the operation.

[0008] With respect to the change with time of the expansion pressure acting on the furnace wall, in the region where the charging density realized by the humidified coal or the preheated coal is high, the expansion pressure when the softened molten layer meets at the center of the carbonization chamber is reduced. It is known that the gas has a remarkably high value (maximum value) and that the pressure of the gas in the softened molten layer is the cause of the expansion pressure. Further, the expansion inert material (coke, anthracite, semi-anthracite, semi-coke, petroleum coke, Do <br/> Isumizai of caking property) or added, by reducing the particle size of the coal itself It is known that the pressure is reduced.

The present inventors have found that in coal having a high volatile content and a large amount of inactive components in the coal microstructure component, the gas pressure in the softened molten layer is reduced. The inventors also
Since the expansion pressure shows a remarkably high value (maximum value) only when the softened molten layer associates at the center of the carbonization chamber, it has been found that if only this maximum value can be reduced, the influence on the furnace body can be reduced as much as possible.

[0010] From these facts, the present inventors have found that, without reducing the expansion pressure throughout the carbonization time, blended coal containing an inert substance near the associating position of the softening molten layer (the center in the width direction of the furnace in the carbonization chamber) or volatile coal High coal content, high content of inert components in coal microstructure component, small particle size coal, low caking coal, and only the gas pressure in the softened molten layer during the softened molten layer association It has been found that by reducing the pressure, the maximum inflation pressure can be reduced without substantially impairing the coke strength.

The present invention has been completed based on the above findings.
That is, different blended coals are charged in the width direction of the coking chamber of the coke oven, and as the blended coal charged into the center of the coking chamber where the softened molten layer meets, the gas pressure in the softened molten layer is low. Maximum expansion by using charcoal (coal coal with high volatile content, large amount of inert component in coal microstructure component, small particle size coal, low caking coal, and coal containing inert substance) It is possible to suppress the pressure.

Since the coke in the center of the carbonization chamber is originally a portion having a large porosity and a low strength,
Only in the center of the carbonization chamber, preferably 10mm-100m
Even if the above-described low-coking coal blend or a coal blend containing an inert substance is used in a region of about m width, the coke strength of the entire coking chamber does not decrease, and the problem of the related art can be solved. It is possible.

[0013]

【Example】

Example 1 In Experiment 1, blended coal A in which four types of coal (crushed particle size-3 mm 85%) as shown in Table 1 were blended at a ratio as shown in Table 2, the total amount, furnace width 400 mm, height 600 mm ,
Charge density 0.85d in test coke oven 600mm long
The mixture was charged at ry-t / m ³ and carbonized at a furnace temperature of 1250 ° C. for 18 hours, and the expansion pressure in the coal carbonization process was measured.

On the other hand, in Experiment 2, as shown in FIGS. 1 (a) to 1 (c), the coal charging hopper 1 was modified so that coal blend A was supplied to the furnace wall side and coke breeze (particle size: 0.5% or less 98%). Blended coal B containing 5% was charged into the center, and the expansion pressure was measured in the test furnace described above. At this time, the charging density is 0.85 dry-
t / m ³ , and the weight ratio of blended coals A and B is A 90%
B was set to 10%.

The coke after carbonization is dry-fired with nitrogen gas, and the drum strength (according to JIS K 2151)
And the strength after reaction (strength after reaction with carbon dioxide at 1100 ° C. for 2 hours).

The results of the above test are shown in FIG.

In contrast to Experiment 1, Experiment 2 in which the present invention was implemented
In this example, the expansion pressure was substantially the same until about 12 hours when the softened molten layer was associated, but the maximum expansion pressure at the time when the softened molten layer was associated was reduced by almost half. In this case, it is also found that the coke strength hardly decreased.

Example 2 In Experiment 1, blended coal A shown in Table 2 was carbonized in the same test coke oven as in Example 1, and the expansion pressure in the coal carbonization process was measured.

On the other hand, in experiment 2, a coal charging hopper 1 modified as shown in FIGS. 1 (a) to 1 (c) was used, and the coal blend D was placed on the furnace wall side. Blended coal C having a large amount of inactive components in the tissue components was charged into the center, and the inflation pressure was measured. At this time, the weight ratio of the blended coals C and D was C 50% D 50%. When C and D are mixed in equal amounts, the result becomes the same as A.

The coke after carbonization was subjected to dry fire extinguishing with nitrogen gas, and the drum strength and post-reaction strength were measured as in Example 1.

Table 4 shows the results of the above test.

In contrast to Experiment 1, Experiment 2 in which the present invention was implemented
In, the maximum expansion pressure at the time of associating the softened molten layer was reduced by about 20%. Also, in this case, it can be seen that the coke strength hardly changes.

[0023]

[Table 1]

[0024]

[Table 2]

[0025]

[Table 3]

[0026]

[Table 4]

[0027]

As described above, according to the present invention, different coking coals are inserted in the width direction of the coking chamber of the coke oven of the coke oven type so that the coke strength can be reduced without reducing the coke strength. Can be suppressed. Therefore, according to the present invention, stable coke oven operation can be continued while avoiding furnace body damage due to expansion pressure, and it is possible to increase the use of high inertia coal having a high expansion pressure and a high degree of coalification. Range can be expanded. In addition, even in an environment in which the bulk density of coal is increased due to charging of humidified coal or preheated coal and the maximum expansion pressure is increased, application of the present invention suppresses the maximum expansion pressure and increases productivity. Is possible, and the economic effect is great.

[Brief description of the drawings]

FIG. 1 is a view showing a hopper for charging different coals in a furnace width direction in an embodiment, FIG. 1 (a) is a front view,
(B) is a plan view, and (c) is a side view.

FIG. 2 is a graph showing the change over time of the expansion pressure.

[Explanation of symbols]

 1: hopper

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) C10B 47/10 C10B 57/04

Claims (4)

(57) [Claims] When a raw coal is charged into a room-type coke oven and carbonized, a coal blend containing a carbon material having poor caking properties is charged into a region of 10 mm to 100 mm in a central portion in a furnace width direction. A method of operating a coke oven characterized by the above-mentioned. 2. When charging raw coal in a room-type coke oven and dry-distilling the coal, a coal having a higher volatile content in a 10 mm to 100 mm region in the central part in the furnace width direction than a blended coal charged on the wall side.
A method for operating a coke oven, comprising charging a coal blend containing a large amount of inert components in a microstructure component . 3. A coal blend having a smaller particle size than a coal blend charged into a wall in a 10 mm to 100 mm region in a central portion in a furnace width direction when raw coal is charged into a room-type coke oven and carbonized. A method for operating a coke oven characterized by charging a coke oven. 4. When charging raw coal in a room-type coke oven and dry-distilling it, a coking coal of a coking coal charged into a wall of 10 mm to 100 mm at the center in the furnace width direction is used as compared with coal blended into a wall . A method of operating a coke oven characterized by charging low blended coal.