JPS604238B2 - Method for detecting carbon adhesion in coke oven carbonization chamber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for detecting the adhesion state of carbon adhering to the wall surface of a carbonization chamber of a coke oven.

In a coke oven, carbonization is carried out by charging coking coal into a carbonization chamber and heating it by burning gas in an adjacent combustion chamber. Carbon adhesion cannot be avoided. When removing coke from the carbonization chamber of the above coke oven,
An extrusion load acts on the extruder, and this load varies depending on the amount of attached carbon, coal quality, coke oven operating conditions, fire-off conditions, etc. In particular, attached carbon is a major factor in increasing the extrusion load, and carbon When the adhesion becomes noticeable, so-called clogging or stagnation occurs, which makes it impossible to extrude coke.

Therefore, it is necessary to remove carbon adhesion before it becomes noticeable. Conventionally, adhering carbon has been detected visually, but it has been impossible to accurately determine the amount and state of adhesion by looking into the high-temperature carbonization chamber.

Therefore, a method was devised to convert the extrusion load of the extruder into an extrusion current and check the change in this extrusion current to detect the state of carbon adhesion.

The relationship model between the extrusion current value and extrusion time in this case is
As shown in the figure, since the coke is ejected from the kiln against the frictional resistance of the coke oven wall, the load on the extruder becomes significantly high at the beginning of ejecting from the kiln, and the coke extrusion movement stops when the peak current value is reached. After that, the current value decreases as the extrusion load decreases.

When the extrusion load is small, it decreases almost smoothly as shown in Figure 1a, but when carbon adhesion is large, the extrusion load increases partially as shown in Figure 1B, and the abnormal current value peaks. appears. However, it is actually almost impossible to detect abnormal current values from the extrusion current pattern on a chart paper of a current recorder attached to the extruder and determine the timing of carbon shedding. In other words, Fig. 2 shows the furnace height 6
The extrusion current pattern on the chart paper of the current recorder before and after carbon scraping and carbon scraping in a skin coke oven shows the change in the abnormal current peak value. The abnormal current peak values before and after scraping hardly change, and the reduction in extrusion load due to the reduction in adhering carbon due to carbon shedding and carbon sloshing cannot be read from the abnormal current peak values.

This indicates that carbon adhesion to the carbonization chamber cannot be determined from the abnormal current peak value, and it is hoped that a method for detecting carbon adhesion that can clearly confirm carbon adhesion to the carbonization chamber will be developed. ing.

In order to eliminate such drawbacks of the conventional methods, the present inventors have conducted various tests and research, and have clearly determined carbon adhesion by expressing the extrusion load from the time-integrated value of electric power or the time-integrated value of current during coke extrusion. He discovered what could be done and completed this invention.

That is, this invention detects the extrusion load applied to the coke extruder of each kiln by converting it into a time-integrated value of electric power or a time-integrated value of current when unloading coke from a coke oven, and The gist is to detect carbon adhesion by comparing it with standard values set for each kiln.

Time integrated value of extrusion load power applied to the coke extruder (
(hereinafter referred to as electric power) can be digitally recorded by installing a power meter in the extruder.

Moreover, the time integrated value of the current may be digitally recorded by installing a current integrator in the extruder. In addition, in coke ovens, there are differences in extrusion load depending on the history of each kiln, so
It is necessary to accumulate the detected power amount or current integrated value for each kiln over a certain period of time to obtain an average value, and set a reference value for each kiln based on this. By comparing the detected values with the set reference values for each kiln, it is possible to determine the amount of carbon adhesion, determine the timing of carbon scraping, and determine the necessity of carbon scraping.

Note that the reason for converting the extrusion load during coke extrusion into the electric energy or current integrated value is because the voltage applied to the extruder is usually approximately constant (for example, 220 V or 440 V).
If the extrusion power changes in response to a change in the extrusion load, the extrusion current naturally changes in proportion to the change in the extrusion power.

Therefore, measuring either the extrusion power or the extrusion current corresponds to a change in the extrusion load, and measuring the electric energy or current integrated value during extrusion can represent the total extrusion load. Therefore, compared to the conventional method of checking furnace wall carbon adhesion by abnormal peak values of extrusion current or extrusion power, the extrusion load The size of the carbon is clarified, and the carbon adhesion is determined by comparing it with the standard amount set for each kiln based on the history of each kiln, so it is possible to determine the exact timing of carbon scraping and whether carbon scraping is necessary. Can be done.

Now, in a coke oven with a furnace height of 6, a furnace depth of 450 mm, and an oven length of 15.56 mm, the coke extruder is operated with a constant voltage of 440 V in 3 phases every 5 furnaces from 6 to 3. Figure 3 shows the change in extrusion load when the extrusion load is changed using a conventional extrusion current pattern.

In this invention, the extrusion load is detected by converting it into the electric energy or the time integrated value of the current.
Comparing the amount of electric power for 1 neck sand from immediately after the start of coke movement between No. 8 (without carbon adhesion) and No. 8 (with carbon adhesion), the electric power of Kiln No. 7 was 18 h, and that of Kiln No. 83 was 32 h.
This is expressed as the amount of power corresponding to the area of the hatched part in the drawing, and the difference is detected as 13s h.

In addition, a method for detecting the extrusion load based on the amount of electric power was carried out in parallel with the current recorder of the extruder before and after carbon burning (empty kiln) and carbon scraping as shown in FIG.

The results are shown in FIG. Note that the dashed-dotted line in Figure 4 is
The standard values set for each kiln are shown. As shown in Figure 4,
According to this invention, which converts and displays the extrusion load into electric energy, when the adhering carbon decreases due to carbon burn-off and carbon scraping in an empty kiln, the extrusion electric energy clearly decreases, and each It was lower than the standard value set for each kiln, which corresponds well to carbon adhesion. This shows that increases and decreases in carbon adhesion, which cannot be detected using the abnormal current peak values of conventional extrusion current recorders, can be detected by using the extrusion power amount, and also can be compared with the standard value for each kiln. This shows that by comparing the results, it is possible to formulate a carpon burnout schedule, etc. Figure 5 shows
This is a comparison of the extrusion power amount when this invention is implemented for each kiln of each "kiln exit group" in the coke oven described above, and the ■ mark in the figure indicates the case where empty kilns have been operated for the past year. This corresponds well with the extrusion power amount for the kilns that did not use this method, indicating that the amount of carbon deposited was large.

By comparing the extrusion power amount of each kiln with the preset reference power amount for each kiln, the transition of carbon adhesion can be clearly detected and carbon management can be quantified. In addition, in coke ovens where combustion management is carried out by computer, the amount of electricity for each oven is input into the computer,
It is possible to schedule empty kilns, display kilns that require attention, etc. As mentioned above, this invention detects the extrusion load at the time of unloading the kiln as the amount of electricity and compares it with the preset reference amount of electricity for each kiln to determine carbon adhesion. Compared to the conventional method, it is possible to clarify changes in the amount of carbon adhesion, quantify carbon management, and accurately judge carbon adhesion.

[Brief explanation of drawings]

Figures 1a and 1b are charts showing extrusion current patterns during coke exit from a coke oven, where a shows a case where there is little carbon adhesion and b shows a case where there is a lot of carbon adhesion. Figure 2 is a chart showing carbon scraping due to an empty oven in an actual coke oven, and changes in the abnormal current peak value of the extrusion current pattern when the coke oven is discharged before and after carbon scraping.
The figure is a chart comparing extrusion current patterns in actual coke ovens for each kiln, Figure 4 is a diagram showing changes in the extrusion power amount of this invention corresponding to Figure 2, and Figure 5 is a diagram according to this invention. It is a chart showing the extrusion power amount of each kiln for each kiln output group of a coke oven. Figure 2 Figure 4 Figure 1 Figure 5 Ship

Claims (1)

[Claims] 1 When unloading coke from a coke oven, the extrusion load applied to the coke extruder for each kiln is converted into a time-integrated value of electric power or a time-integrated value of current, which is then detected and set in advance for each kiln based on the history of each kiln. A method for detecting carbon adhesion in a coke oven carbonization chamber, characterized by detecting carbon adhesion by comparing it with a reference value.