JPS5953587A - Detection of carbon deposition in coke oven carbonizing chamber - Google Patents

Abstract

PURPOSE:To avoid carbon deposition to the wall of coke oven carbonizing chamber by detecting the degree of deposition through the load applied to the coke extruder on operation. CONSTITUTION:When delivering a coke from oven, for each oven the condition of the carbon deposited to the wall of the carbonizing chamber of the oven is detected by converting the load applied to the coke extruder to the time-cumulative value of electric power or current to compare the value with the standard established for each beforehand based on the respective oven experience, thus leading to the prevention of the carbon deposition due to repeated dry distillation in the chamber.

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.However, due to the repeated carbonization in the carbonization chamber, carbon is deposited on the wall of the carbonization chamber. adhesion cannot be avoided.

When coke is discharged from the carbonization chamber of the above-mentioned coke oven to the kiln, 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 condition, etc. Carbon adhesion is a major factor in increasing extrusion load, and when carbon adhesion becomes noticeable,
So-called clogging, stagnation, etc. occur in which coke cannot be extruded. 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 1 (a), but when carbon adhesion is large, the extrusion load increases locally as shown in Figure 1 (B) and becomes abnormal. A peak of current value appears. However, it is actually almost impossible to read the abnormal current value from the extrusion current pattern on the chart paper of the current recorder attached to the extruder and determine the timing of carbon burn-off.

In other words, Fig. 2 shows the change in abnormal current peak value of the extrusion current pattern of the chart paper of the current recorder before and after carbon burning and carbon scraping in a coke oven with an oven height of 6 m. As shown in , the abnormal current peak values before and after carbon burning off and carbon scraping are almost unchanged, and the reduction in extrusion load due to the reduction of adhering carbon due to carbon burning off and carbon scraping is less than the abnormal current peak value. cannot be read.

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, as a result of various tests and studies, have expressed the extrusion load by the time-integrated value of electric power or the time-integrated value of current during coke extrusion.
They discovered that carbon adhesion could be clearly determined 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 a coke oven, the extrusion load differs depending on the history of each kiln, so the electric energy or current integrated value detected above for each kiln is accumulated over a certain period of time to obtain an average value, and based on this, each kiln is It is necessary to set a reference value for each case.

By comparing the detected values with the set standard values for each kiln, it is possible to determine the amount of carbon adhesion, determine the timing of carbon burning off, and determine whether or not carbon scraping is necessary.

Note that the extrusion load during coke extrusion is converted into electric power or current integrated value because the current applied to the extruder is generally constant (for example, 220V or 440V), so the extrusion load is If the power changes, the extrusion current will naturally change 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 burning off and whether or not carbon scraping is necessary. I can do it.

Currently, in a coke oven with an oven height of 6 m, an oven width of 450 m, and an oven length of 15.56 m, kilns No. 63 to No. 88 are arranged in 3-phase 4-phase ovens every 5 kilns.
The change in extrusion load when the coke extruder is operated at a constant voltage of 40V is illustrated in FIG. 3 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 power consumption for 18 seconds immediately after the start of coke movement between No. 83 (with no carbon adhesion) and No. 83 (with carbon adhesion), the amount of electricity consumed for 18 seconds from the start of coke movement was 189 wh for kiln No. 78 and 3 for kiln No. 83.
22wh, and it is expressed as the amount of power corresponding to the area of the hatched part in the drawing, and the difference is 133w.
Detected as h.

In addition, a method for detecting extrusion load based on electric power was carried out in parallel with the current recorder of the extruder before and after carbon burning off (empty kiln) and carbon scraping 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 is reduced by burning off carbon in an empty kiln or scraping off carbon, the extrusion electric energy clearly decreases in both cases. It is also 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 indicate that the standard value for each kiln can be detected by using the extrusion power amount. This shows that it is possible to formulate a carbon burn-off schedule, etc. by comparing with the above.

Figure 5 shows the "burning group" in the coke oven mentioned above.
This figure shows a comparison of the extrusion power amount when this invention is implemented for each kiln, and the black mark in the figure shows the extrusion power amount and It corresponds well, indicating that the amount of carbon adhesion is 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 that use computers to control combustion,
By inputting the amount of electricity for each kiln into the computer, it is possible to schedule empty kilns, display kilns requiring attention, etc.

As described above, this invention detects the extrusion load at the time of unloading the kiln as the amount of electric power, and compares it with the preset reference amount of electric power 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]

FIGS. 1(a) and 1(b) 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 large amount of carbon adhesion. Figure 2 is a chart showing carbon burn-off in an empty oven in an actual coke oven, and changes in abnormal current peak values of the extrusion current pattern at the time of ejection from the coke oven 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. Applicant Sumikin Chemical Co., Ltd.

Claims (1)

[Claims] When unloading coke from a coke oven, the extrusion load applied to the coke extruder for each kiln is detected by converting it into a time-integrated value of electric power or a time-integrated value of current, and is 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.