JP2003064378A - Method for coke oven operation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for coke oven operation, with which trouble occurrence frequency in coke oven operation can be controlled by using an index to be measured more easily than swelling pressure. SOLUTION: In the production of coke by a coke oven, an index X obtained by a numerical expression (1) X=a×A+b×B+c...(1) (a, b and c are each a constant; A is an index determined by blending of raw materials and is obtained on the basis of at least one of the maximum fluidity (MF) of raw material, volatile matter (VM) on dry ash-free basis of raw material and total inert component amount (TI) of raw material; B is coal feed amount per furnace on anhydrous base) is controlled in a fixed value or smaller than it.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a desirable operation method for dry-coiling coal or the like to produce coke in a coke oven, and more particularly to selection of raw materials, blending method and charging amount.

[0002]

2. Description of the Related Art In a horizontal chamber type coke oven, the following steps are generally carried out when carbonizing carbons to produce coke.

First, the particle size of coal having appropriate properties is adjusted,
If appropriate, after partial drying, it is introduced into the coking oven carbonization chamber. The coke oven is called a carbonization chamber and has a width of about 0.3.
A space of about 0.6 m, a height of about 4 to 8 m, a length of about 10 to 20 m; About 10 to 50 sets are installed alternately. A burner structure or the like is installed in the combustion chamber so that gas can be combusted, and the coal in the carbonization chamber is heated and carbonized by the heat from the combustion chamber. About 1
If heating is continued for 5 to 24 hours, the coal in the carbonization chamber will be about 10
It becomes coke at 00 ° C. After that, the furnace lids installed at both ends of the carbonization chamber in the length direction are removed, and red hot coke is extruded from one side and cooled to obtain product coke.

The structure of the coke oven is composed of bricks, and once the temperature is raised at the start of operation, the heating is continued for about 30 to 50 years without cooling normally. In the unlikely event that the brick is damaged, it must be repaired without cooling the furnace body, so it is generally not easy to repair the brick, which is the coke oven structure, and the coke oven operates smoothly. For that, it is extremely important to prevent damage to the bricks.

Various methods have been proposed for the selection and blending of raw materials, but in many cases, the selection has been made with the aim of obtaining coke having a desired quality (for example, Miyazu et al. Nippon Steel Tube). Technical Report, No. 67, 125, (1
975)). On the other hand, it is known that depending on the raw material blending conditions and operating conditions, it has an unfavorable effect on the brick structure of the furnace body. is there.

For example, Japanese Patent No. 2561211, Japanese Patent Laid-Open No. 7-268348, Japanese Patent Laid-Open No. 10-245566.
Japanese Patent Application Laid-Open No. 11-303661 and Japanese Patent Application Laid-Open No. 11-303661 describe a method for blending raw materials for suppressing expansion pressure in order to prevent damage to the furnace wall due to expansion pressure of coal during coal carbonization.

Further, it is known that if the resistance of the coke extruded from the furnace becomes excessively large, an excessive load is applied to the furnace wall, which may cause damage to the furnace wall. Therefore, the property of the raw material is controlled. Therefore, a method for improving the extrudability of coke has also been proposed. For example, JP-A-7-278
In Japanese Patent No. 562, the maximum expansion pressure is estimated from the properties of the blended coal by a calculation formula, and the value is controlled to cause a clogging (a resistance at the time of extrusion becomes excessive, and coke cannot be discharged from the furnace). Methods to prevent it have been proposed. In Japanese Patent Laid-Open No. 8-283730, the amount of horizontal burnout of coke is obtained in advance in a test furnace.
A method for preventing clogging by controlling the operation by using this is described.

[0008]

Each of the above-described methods of selecting various raw materials for preventing damage to the furnace body has its own problems.

That is, in the method of using the expansion pressure as a management index of the raw material mixture, the measurement is complicated. In order to measure the expansion pressure during coal carbonization, generally, several tens of kg or more of coal is used, and a test carbonization furnace having a special furnace wall for measuring the generated pressure is required. Such a test carbonization furnace is also required when determining the amount of horizontal burnout in the technique disclosed in Japanese Patent Laid-Open No. 8-283730.

The present invention solves such a problem and provides a coke oven operating method capable of controlling the frequency of trouble occurrence in coke oven operation using an index that is easier to measure than the expansion pressure. To aim.

[0011]

Means for Solving the Problems The present inventor has studied the evaluation of coke extrudability using an index that is easier to measure than expansion pressure. As a result, the index A obtained based on at least one of the maximum fluidity of the raw material, the ashless standard volatile content of the raw material, and the total amount of inert components of the raw material, and the charging amount B have a great influence on the occurrence of extrusion trouble. I found out that. Then, it was found that the index X obtained from the index A and the charging amount B has a correlation with the occurrence frequency of trouble rather than the measured expansion pressure, and the invention of the method for operating a coke oven described below was reached. It was

That is, the invention of claim 1 is a method for operating a coke oven, which is characterized in that when the coke is produced in the coke oven, the index X obtained by the equation (1) is controlled to be a certain value or less. , The above-mentioned subject was solved.

[0013]

[Formula 3] X = a × A + b × B + c ········ (1)

Where a, b and c are constants.

A is an index determined by the blending of the raw materials, and is used as at least one of the maximum fluidity (MF) of the raw materials, the anhydrous ashless standard volatile matter (VM) of the raw materials, and the total amount of the inactive components (TI) of the raw materials. Required based on

B is the amount of coal charged per kiln on a dry basis.

Raw material maximum fluidity (MF), raw material anhydrous ashless standard volatile matter (VM), total raw material inactive ingredient content (TI)
And, the numerical values necessary for the calculation of the coal charging amount per kiln on the anhydrous basis are the values obtained in the daily analysis of the raw material coal, and according to the present invention, in a coke oven without performing a complicated carbonization test. It is possible to predict the trouble frequency and prevent the damage to the furnace body caused thereby. In addition, by considering the amount of coal charged, the trouble frequency can be predicted more accurately.

The present inventor also calculated the following γ on the basis of the curve of the cubic equation using anhydrous ashless standard volatile matter (VM) for the raw plain coal and the cubic equation For specific brands that do not apply, the following α and β are calculated by classifying based on the maximum fluidity (MF), anhydrous ashless standard volatile matter (VM) of the raw material, and total inactive ingredient amount (TI) of the raw material. It was found that the index X having a correlation with the trouble occurrence frequency can be calculated with higher accuracy by calculating the index A by doing so.

That is, the invention of claim 2 is characterized in that, in the method for operating a coke oven according to claim 1, the index A is calculated by the following mathematical expression (2).

[0020]

[Equation 4]

It is possible to more accurately calculate the index X by predicting α, β, γ and calculating the index A by classifying the materials for each brand of raw material, and thus predicting the trouble frequency. Also, α of coal that does not apply to the above case classification,
β and γ are set to 0.

[0022]

DETAILED DESCRIPTION OF THE INVENTION A method of operating a coke oven according to an embodiment of the present invention will be described below.

First, as for the raw material to be charged into the coke oven, a value required for calculation is obtained for each handle. Specifically, MF
Is the method shown in JISM8801, VM is JISM
8812 is measured by the method shown in 8812.
816 is calculated from I and SF among the results of the fine structure component analysis of coal obtained by the method shown in FIG.

[0024]

[Equation 5] TI = I−g × SF + MM ... (3) (g is a constant, MM is a value calculated by the method described in JISM8810 explanation)

Next, the raw materials are classified by brand into those belonging to α, β and γ and those other than that, and each is calculated by the following formula.

[0026]

[Equation 6]

However, f is f = f1 × VM ³ + f2 × V
The larger value of the numerical value calculated by M ² + f3 × VM + f4 and 0. Here, for example, f1 = 0.2 to 0.4, f
2 = −30 to −10, f3 = 400 to 600, f4 = −
Numerical values of 50,000 to -3000 can be used, and more specifically, f1 = 0.2969, f2 = -21.
The numerical values of 6, f3 = 517.8 and f4 = -4076 can be used. That is, f = 0.2969 × VM ³
The calculation formula of −21.6VM ² + 517.8VM-4076 can be used.

When a plurality of brands are included, α and β are calculated by using the total of the mixture ratios. γ is obtained by finding f for each brand and adding up the numerical values obtained by multiplying the brand. From the above, the index A determined by the blending of the raw materials can be obtained.

Further, the mixing ratio of B and each brand is obtained from the operating conditions of the coke oven, and the value of X is calculated according to the equation (1).

[0030]

[Formula 7] X = a × A + b × B + c ······ (1)

Here, a, b and c are constants (regression coefficients) obtained by regression.

The obtained X is compared with a preset reference value, and if the X is smaller, the operation is carried out, and if the X is larger, the blending ratio of each brand is adjusted. Depending on whether B is adjusted or not, the operation condition is set so that the value of X becomes equal to or less than the reference value and the operation is performed.

Here, the reference value necessary for comparison with X may be determined based on the relationship between X and the trouble frequency from the operation results (for example, the upper limit value of the trouble frequency to the value of X). The desired value may be set based on theoretical consideration, or may be set in consideration of the safety factor in those values.

[0034]

[Example] X when varying the properties of the blended coal and the amount of coal
Figure 1 shows the correlation between the occurrence frequency of coke extrusion problems. From this figure, it can be seen that X calculated by the equation (1) has a good correlation with the frequency of occurrence of extrusion trouble. For example, if you set the allowable trouble frequency to 5%,
It is understood that the blended coal composition and the charging amount should be controlled so that the value of X is about 6 or less.

[0035]

Comparative Example The expansion pressure was measured for the same blended coal for which X was obtained in the examples, and the result of investigating the correlation with extrusion trouble is shown in FIG. Comparing FIG. 1 and FIG. 2, it can be seen that the correlation between the inflation pressure and the trouble occurrence frequency shown in FIG. 2 is smaller than the correlation between X and the trouble frequency shown in FIG. It is understood that the trouble occurrence can be estimated more accurately by the method according to the present invention shown in the embodiment, as compared with the case where the trouble occurrence is estimated only by the expansion pressure.

[0036]

According to the present invention, it is possible to control the frequency of occurrence of troubles in the operation of a coke oven without using a complicated means of measuring the expansion pressure. That is, the method of the present invention has an effect of contributing to the extension of the life of the coke oven by avoiding the operational failure, the production reduction, etc. due to the trouble and preventing the damage of the coke oven.

[Brief description of drawings]

FIG. 1 is a graph showing a correlation between an index X of the present invention and a trouble occurrence frequency.

FIG. 2 is a graph showing a correlation between a conventional expansion pressure and a trouble occurrence frequency.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hidekazu Fujimoto             1-2-1, Marunouchi, Chiyoda-ku, Tokyo             Main Steel Pipe Co., Ltd. F-term (reference) 4H012 LA03

Claims (2)

[Claims] 1. A method of operating a coke oven, which comprises controlling an index X, which is obtained by the formula (1), to a certain value or less when producing coke in the coke oven. [Formula 1] X = a × A + b × B + c (1) where a, b, and c are constants. A is an index determined by the blending of the raw materials, and is determined based on at least one of the maximum fluidity (MF) of the raw materials, the anhydrous ashless standard volatiles (VM) of the raw materials, and the total amount of inert components (TI) of the raw materials. To be B is the amount of coal charged per kiln on a dry basis. 2. The coke oven operating method according to claim 1, wherein the index A is obtained by the following mathematical expression (2). [Equation 2]