JPH07108978B2 - Coke oven carbonization control method - Google Patents

Description

The present invention relates to a carbonization control method for carbonizing carbon by a coke oven.

[Conventional technology]

Conventionally, in order to produce high quality coke in a coke oven, for example, a pretreatment method such as a forming coal blending method or a coal classification and pulverization method has been adopted.

Apart from such a method, a method has recently been proposed in which the heating pattern in the carbonization process is changed to produce high-quality coke or energy is saved.

For example, in JP-A-58-222183, it is clarified that the coke quality is governed by the temperature rising rate in the softening and melting zone of the coal and the temperature of the output kiln coke, and the temperature of the output kiln coke is at the same level as in the normal operation method. While maintaining
A method of setting a heating pattern so that the temperature rising rate is 5 ° C./minute or more is disclosed.

Further, in JP-A-59-179581, a timing for switching from a large flow rate heating at the initial stage of carbonization to a small flow rate heating as a method for improving the coke quality, particularly the strength after hot reaction, while saving energy of about 10%. The charcoal temperature is 350
It is disclosed to be carried out when the temperature reaches ~ 700 ° C.

The former aims at maximizing the effect of improving the quality of coke by using the energy required for carbonization as the level of the normal operation method, and the latter aims at both energy saving and quality improving effect. However, depending on the content of the heating pattern in the carbonization process, it is possible to make the coke quality level equal to normal operation and maximize energy saving.

What kind of heating pattern to use, that is, how to set the respective merits of energy saving and quality improvement effect, depends on the coking coal situation, energy price system, etc. Good.

This selection will result in 100% quality improvement benefits as described above.
% (Energy saving merit is 0%) to 0% (energy saving merit is 100%), but in any case, when producing coke, the operator sets a target value and achieves it. Must.

That is, it is important for coke production to set the quality improvement target value (inevitably, the energy saving target value is determined) and to achieve it.

On the other hand, none of the above proposals describes a general heating pattern, and does not guarantee that the discharged coke is maintained at the target quality. Even in the latter case, when the charging charcoal property (for example, water content) changes, the time to reach a constant temperature in the coal (350 to 700 ° C) changes (that is, the heating rate also changes, The coke quality also changes), so when switching the fuel from a large flow rate to a small flow rate, the temperature in the coal is 350 to 700 ° C.
It does not guarantee that the target coke quality will be obtained.

[Problems to be solved by the invention]

The present invention has a coke quality of a softening / melting zone of coal (approximately 300
Focusing on the fact that it is mainly controlled by both the rate of temperature rise and the temperature of the kiln coke at ~ 500 ° C), the coke production method that guarantees the target coke quality by adopting the carbonization control method that links both Is provided.

[Means for solving problems]

The carbonization control method of the present invention, based on the target coke quality set in the coke oven, sets a target value for the heating rate and the output kiln coke temperature in the softening and melting zone of coal, and the actual value of the heating rate during carbonization. Is calculated by comparing the temperature rise rate with the temperature rise rate, and the target value of the output oven coke temperature is corrected based on the calculated deviation, and the subsequent heating pattern is corrected.

[Examples] Hereinafter, the features of the present invention will be specifically described based on Examples with reference to the drawings.

FIG. 1 is a flow chart for explaining the carbonization control method of the present invention, and FIG.
The figure is a control block diagram, and FIG. 3 is a diagram showing an example of a heating pattern.

1 and 2, the target value of coke quality is
As described above, the operator compares the energy saving level with, for example, the most economical design and determines the target values of the heating rate and the output kiln coke temperature in the softening and melting zone of the coal based on the design.

The following equations are used to determine these two target values.
The CSR indicates the strength of coke after the hot CO ₂ reaction.

Carbonization heat _{(H c) = aT c +} b ...... However, T _c is Dekama coke _{temperature, CSR = cT c + dV c} + e ...... However, V _c is the heating rate.

That is, by designing the amount of dry distillation heat to a certain level, the temperature of the output coke coke is determined, and then the required heating rate is determined from the design value of coke quality (CSR). The formula is determined by the coal properties and is not necessarily limited to the above.

Next, a heating pattern that achieves these two target values is generated. This generation is based on the simulation result of the coke oven heat transfer model.

This heating pattern may be the flow rate of heating fuel,
It may be generated as the carbonization furnace temperature (combustion chamber temperature).

FIG. 3 shows a case where the carbonization furnace temperature is generated.

When the coal is charged into the coke oven, heating and dry distillation are advanced according to the heating pattern, and the actual heating rate in the softening and melting zone of the coal is detected. Next, the actual temperature increase rate is compared with the target temperature increase rate, and the deviation (deviation) of the coke quality from the target value due to this deviation is calculated. This calculation is performed based on the above formula.

The actual heating rate can be detected by inserting several thermocouples in the width direction of the kiln and measuring the temperature of the heating. In addition to this, there is a strong link with the heating rate. It may be estimated from various carbonization phenomena (for example, the changing point of the water content in the generated gas, the changing point of the gas composition, the gas temperature, the gas flow rate, etc.).

Next, in order to correct the deviation (deviation) of the coke quality from the target value, the target firing coke temperature is modified,
Based on this, the subsequent heating pattern is corrected. The target kiln coke temperature is corrected based on the formula.

The temperature of the kiln coke may be detected and calculated by a radiation thermometer provided in the coke guide vehicle, a furnace wall temperature provided in the extruder ram head, or the like. Then, the deviation between the actual output kiln coke temperature and the target output kiln coke temperature is taken into the generation of the heating pattern in the next cycle, and the deviation can be minimized. Further, the deviation between the target temperature increase rate and the actual temperature increase rate is also incorporated in the heating pattern generation in the next cycle.

The example of FIG. 3 shows the carbonization time for 11 coke ovens.
It shows the results of applying the present invention during 24-hour operation.

That is, this example is an example in which the actual value of the heating rate is estimated and detected at 15 hours and 30 minutes after the coal is charged, and the subsequent heating pattern is changed in accordance with the deviation from the target value.

The operation specifications at this time are shown in Table 1 together with other cases.

Due to the modification of the heating pattern in the latter half, the coke quality (CSR) without modification is -1.2 to + relative to the target value.
The change was maintained at ± 0.2% while the change was 0.7%, and the effect could be clearly recognized.

In addition, the deviation of the actual heating rate from the target heating rate in Table 1 is due to normal coal properties (water, volatile matter, charging amount, etc.).
Occurs within the change range of.

〔The invention's effect〕

As described above, in the present invention, the coke satisfying the target coke quality is surely produced by incorporating the temperature rising rate and the temperature of the output kiln coke as control factors in the temperature range in which coal softens and melts. It becomes possible to do.

[Brief description of drawings]

FIG. 1 is a flow chart showing control in the embodiment of the present invention, FIG. 2 is a block diagram showing a control system used therein, and FIG.
The figure is a diagram showing an example of a heating pattern.

Front Page Continuation (72) Takashi Sato Inventor Takashi Sato 1-1-1, Edamitsu, Hachimanto-ku, Kitakyushu, Fukuoka Prefecture (72) Yoichi Naganuma 1618 Ida, Nakahara-ku, Kawasaki-shi, Kanagawa Address: Nippon Steel & Co., Ltd. First Technology Research Institute (72) Inventor Keihachiro Tanaka 1618, Ida, Nakahara-ku, Kawasaki-shi, Kanagawa Nippon Steel & Co., Ltd. First Technology Research Institute (56) References 56-72076 (JP, A) JP-A-52-12201 (JP, A) JP-A-58-222183 (JP, A)

Claims (2)

[Claims] 1. In a coal carbonization process using a coke oven, target values are set for the temperature rising rate and the output coke temperature in the temperature range in which the charged coal softens and melts, and the heating pattern is set based on the target values. The actual value of the heating rate at the time is compared with the target value of the heating rate to obtain a deviation, and a subsequent heating pattern including the output kiln coke temperature is corrected based on the obtained deviation. Coke oven dry distillation control method. 2. A dry distillation control method for a coke oven, which comprises correcting the heating pattern for the next cycle based on the temperature rise rate and the deviation of the coke temperature in the output kiln according to claim 1.