JPH0153716B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for reliably determining the completion of coke generation, the so-called burnout, when carbonizing coal in a coke oven. In a coke oven, coal is sequentially charged into a large number of adjacent carbonization chambers.
Carbonization is carried out at high temperatures around ℃, and when the carbonization is complete, the coke produced is extruded from the carbonization chamber using an extruder, but before this extrusion operation it is necessary to determine whether or not the carbonization has been completed. The completion of this carbonization is usually called hiochi.

Conventional fire detection is done by a skilled person known as a fire watcher.The method is to open the top cover of the coke oven's gas riser pipe and observe the color of the gas coming out of it. I was determining whether it would fall or not.

However, this method not only requires skill as described above, but also poses a problem in determining when to open the top cover. In other words, if you happen to open the top cover after carbonization is completed, the effect on the coke produced will be small; however, if you open the top cover before carbonization is completed, outside air will flow into the carbonization chamber, causing the coke to deteriorate. This can have a serious negative impact on the quality of coke, and in extreme cases it may not be possible to obtain coke of the desired quality. Therefore, it has been desired to be able to determine whether the fire has fallen off without opening the top cover and without requiring a skilled person.

As a simple method for determining whether a coke oven has flamed out, a relational expression Y'=a'X'+b' can be used between the maximum temperature of the generated gas
There is a method of determining fire-fall by utilizing the fact that (see Japanese Patent Publication No. 46-6497), or a method of determining fire-fall by using the relationship between the elapsed time after coal charging at the time of fire-fall A method for determining fire fall by utilizing the relational expression Y″=a″X″+b″ that holds between
103902) has already been proposed.

However, in both methods, burnout is determined primarily from the generated gas temperature, which changes relatively rapidly at the end of carbonization (i.e., the maximum gas temperature or the gas temperature at the time of burnout), so there is large variation. There is a drawback that the accuracy of judgment is not sufficient.

As a result of various studies aimed at improving the shortcomings of these conventional fire-fall determination methods, the present inventors found that
This has led to the present invention.

That is, the present invention measures the temperature of the gas generated during carbonization in a coke oven at a fixed point from the gas riser pipe to just before the dispersion pipe, and calculates the average temperature in a substantially flat area as the gas temperature changes over time. Relational expression between X and the temperature Y of the same gas at the time of fire loss: Y=aX+b
(In the formula, both a and b are constants determined by the furnace structure, operating temperature, and charging coal conditions such as the moisture content and amount of charging coal.)
During carbonization, the temperature of the same gas is successively measured while operating, and the temperature of the same gas at the time of fire-off, Y ₁ , is determined based on the above-mentioned relational expression from the measured value of the average temperature in the substantially horizontal area obtained at that time, X _{1 .} This is a method to determine whether the fire has fallen by detecting the

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 1 is a partial longitudinal cross-sectional view of an example of a coke oven used in carrying out the present invention.
In the figure, 1 is a carbonization chamber, and 2 is a gas riser pipe for guiding the gas generated in the carbonization chamber 1 to a gas collecting main pipe 6. The rising pipe 2 is connected to the collecting main pipe 6 through its bend part 4. , and a top cover 3 is attached to the riser pipe 2. 8 is a liquid dispersion pipe;
Cooling water (ammonium water) is sprayed from the liquid spray pipe 8 to cool the generated gas. 5 is a thermometer provided in the bend portion 4, and for example, an electric thermocouple is used. The thermometer 5 is preferably provided at the bend 4 of the riser pipe as shown. The reason for this is that the gas temperature at the bend section is lower than that at the riser pipe section, so it is preferable for thermometers such as electric thermocouples, and because the gas temperature at the bend section is more stable than at the riser section, the gas temperature This is because it is possible to more clearly understand the virtually flat range of changes over time. However, if the thermometer is measured after the riser pipe and just before the sprinkler pipe,
It is also possible to provide it at a location other than the bend section, for example, in the middle of the ascending section of the ascending pipe. 7 indicates produced coke.

Charging raw coal using a coke oven as shown in Figure 1 (hereinafter referred to as "charging").
If the temperature of the generated gas is measured sequentially over time from the time of heating until the end of the fire, the temperature changes as shown in Figure 2. That is, the temperature of the generated gas rises rapidly within a relatively short period of time after carbonization, then the temperature gradient gradually becomes gentler, and eventually there is almost no temperature rise or a very small temperature rise. A substantially horizontal and linear temperature gradient section A is reached, and this temperature gradient section A continues for a relatively long time. In this specification, the range of such a substantially horizontal and linear temperature gradient section A is defined as a "substantially horizontal region." After passing through this virtually flat area, the generated gas temperature rises somewhat rapidly again and reaches the highest temperature point B within a relatively short period of time, and then the gas temperature rapidly decreases linearly, and this rapid There is a fire drop point C in the descending area.

If either the generated gas temperature Y at the fire-fall point C or the elapsed time T after coal charging at the fire-fall point C can be known, the fire-fall can be easily determined. The method described in the above-mentioned Japanese Patent Publication No. 46-6497 is a method of measuring and detecting the generated gas temperature Y at the flame-fall point C from the maximum temperature of the generated gas based on the above-mentioned relational expression, and determining the fire-fall. The method described in Publication No. 49-103902 is a method of calculating the generated gas temperature at the target fire-fall time based on the above relational expression and determining the fire-fall. Since the determination is based on the generated gas temperature, which changes rapidly, the accuracy of the determination is not sufficient.

However, according to the research of the present inventors, there is a close relationship between the average temperature X in the above-mentioned substantially horizontal area and the generated gas temperature Y at the time of fire-fall, that is, the relational expression Y=aX+b (in the formula , a, and b are constants determined by the furnace structure, operating temperature, and charging coal conditions such as the moisture content of the charging coal and the amount of charging coal.) It was found that the following holds true.

Therefore, if the constants a and b in the above relational expression are determined in advance in a preliminary operation, then during actual operation, the gas temperature Y at the time of fire-fall in the operation can be calculated from the measured average temperature in the substantially horizontal area X ₁ . ₁ can be easily detected, so it is easy to determine whether the fire has fallen. Moreover, since the average temperature Y in the substantially horizontal region is the gas temperature in a region that occurs in a relatively stable state from the early to middle stages of carbonization, there is little variation, so the method of the present invention that makes judgments based on this , higher determination accuracy can be obtained compared to the above two known methods.

Figure 3 shows the relationship between the average gas temperature (°C) in the substantially horizontal region and the generated gas temperature (°C) at the time of fire-off in a number of model operations, and Figure 4 shows the relationship between the maximum generated gas temperature (°C) in similar model operations. ) and the temperature of the generated gas at the time of fire-off (°C). Figure 5 shows the relationship between the elapsed time after coal loading at the time of fire-off (hr) and the temperature of the generated gas at the time of fire-off (°C) in a similar model operation. This is a plot of actual measurements of the relationships between the two. Note that the temperatures of these generated gases were all measured at the bend portion of the gas riser tube, that is, using the thermometer 5 shown in FIG. In the case of FIG. 3, the variation in measured values is significantly smaller than in the cases of FIGS. 4 and 5. This shows that the determination method of the present invention provides a more accurate determination result than the two known methods.

To determine fire failure using the method of the present invention, a preliminary operation is performed under model operating conditions for each furnace, and a third
The values of the constants a and _b in the above relational expression are determined in advance by collecting the measured data shown in the figure, and in actual operation, the actual value of the average gas temperature in the substantially horizontal region It is sufficient to detect the generated gas temperature Y ₁ at the time of the fire and determine that the flame has fallen at the time when the actual measured value of the generated gas temperature becomes the same value as Y ₁ . In both the model operation and the actual operation, the higher the frequency of gas temperature measurement, the higher the determination accuracy.

Thus, when using the method of the present invention, it is possible to easily determine whether a fire has occurred simply by measuring the temperature of the gas generated during carbonization, which eliminates the conventional method of determining whether a fire has occurred by opening the top cover of the gas riser pipe and observing the flame. There is no risk of degrading the quality of the produced coke, there is no risk of environmental deterioration or energy loss due to gas leakage, and no skill is required. Furthermore, the above-mentioned Japanese Patent Publication No. 46-6497 and Japanese Patent Application Laid-open No. 49
-A more accurate determination result can be obtained compared to the known determination method described in Publication No. 103902.

[Brief explanation of drawings]

Fig. 1 is a partial longitudinal cross-sectional view of an example of a coke oven used to carry out the present invention, and Fig. 2 is a drawing showing the relationship between the generated gas temperature and the elapsed time after carbonization. be. Furthermore, Fig. 3 is a diagram showing the relationship between the average temperature of the substantially horizontal region of the generated gas and the temperature of the generated gas at the time of fire-fall, and Figure 4 is a diagram showing the relationship between the maximum temperature of the generated gas and the temperature of the generated gas at the time of fire-fall. FIG. 5 is a drawing showing the relationship between the elapsed time after coal loading at the time of fire-off and the generated gas temperature at the time of fire-off. Each symbol in the drawings is as shown below. 1... Carbonization chamber, 2... Gas riser pipe, 3... Top cover, 4... Riser pipe bend, 5... Thermometer, 6... Gas collecting main pipe, 7... Produced coke, 8... Sprinkle pipe, A...
Horizontal temperature gradient section, B... Maximum temperature point, C... Fire drop point, T... Elapsed time after coal loading at fire drop, Y... Generated gas temperature at fire drop.

Claims (1)

[Scope of Claims] 1. The temperature of the gas generated during carbonization in a coke oven is measured at a fixed point from the gas riser pipe to just before the dropper pipe, and the average of the substantially flat range of the change in gas temperature over time is determined. Relational expression between temperature
It is a constant determined by the furnace structure, operating temperature, and charging coal conditions such as the moisture content of the charging coal and the amount of charging coal. )
During carbonization, the temperature of the gas is successively measured while the operation is carried out, and from the measured value of the average temperature in _the substantially horizontal area obtained at that time A method of detecting the gas temperature Y ₁ to determine whether the flame has fallen off. 2. The method according to claim 1, wherein the temperature of the generated gas is measured at a gas riser bend section.