JP5369489B2 - Method for estimating temperature distribution in coke oven carbonization chamber, method for operating coke oven, and method for producing coke - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for quantitatively estimating temperature distributions inside carbonization chambers and combustion chambers by a simple method without making a great facility/human investment for providing efficient operation of a coke oven and a technology for manufacturing coke with little quality unevenness. <P>SOLUTION: In the estimation method of the temperature distributions inside the coke oven carbonization chambers in a horizontal chamber coke oven wherein a plurality of carbonization chambers and combustion chambers are arranged alternately, carbonization time in the respective carbonization chambers and representative temperature of the combustion chambers heating the carbonization chambers from their both sides are measured, and then the temperature distribution condition occurring in a certain one carbonization chamber is estimated based on the relationship between the carbonization time in each of the carbonization chambers and a mean value of the representative temperature of the combustion chambers heating the carbonization chambers from their both sides. Preferably, the mean value obtained by performing measurement in each of the combustion chambers under the same condition and carrying out measurement a plurality of times during carbonization of coke in the adjacent carbonization chamber is used as the representative temperature of the combustion chambers. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention estimates the temperature distribution in the coke oven carbonization chamber by a simple method and produces an efficient coke oven by controlling the distribution when carbonizing coal in a horizontal chamber furnace coke oven to produce coke. The present invention relates to a method for operating and reducing coke quality variation.

  When producing coke by dry distillation of coal in a horizontal chamber furnace type coke oven, the following steps are generally taken. First, after adjusting the particle size of coal having appropriate properties and optionally partially drying or molding, it is called a carbonizing chamber of a coke oven, for example, having a width of about 0.3 to 0.6 m and a height of about 4 These are inserted into a sealed space of about 8 to 8 m and a length of about 10 to 20 m. The coke oven is installed with about 10 to 50 pairs of this carbonization chamber and brick structures called a combustion chamber, for example, about 0.5 to 1 m wide and the same height and length as the carbonization chamber. The burner structure etc. which can burn gas are installed in the combustion chamber, and the coal charged into the carbonization chamber is heat-distilled with heat from the combustion chamber. By heating for about 15-24 hours, the coal in the carbonization chamber becomes coke at about 1000 ° C., after which the furnace lids installed at both ends in the longitudinal direction of the carbonization chamber are removed, and red hot coke is extruded from one side and cooled. Product coke is obtained.

  In the above process, temperature control of the combustion chamber for supplying heat to the coal is extremely important. This is because an abnormality in temperature in the combustion chamber directly leads to an abnormality in the dry distillation of coal in the carbonization chamber and causes various troubles. For example, if the temperature of the coal in the carbonization chamber becomes uneven due to temperature variation in the combustion chamber and a part of the carbonized portion remains undried, the variation in coke quality will increase, or the heat shrinkage of the carbonized portion will be insufficient. As a result, it is known that an increase in resistance when extruding coke from the carbonization chamber results in operational trouble. Moreover, if the whole furnace temperature is raised in order to eliminate this non-distilled portion, excessive heat will be given to a certain portion, leading to deterioration in thermal efficiency. Furthermore, if the carbonization time of the carbonization chambers having 10 to 50 groups varies due to the occurrence of the temperature distribution as described above, the schedule for extruding coke from the carbonization chamber is disturbed, and it is difficult to perform efficient operation. .

  However, since the carbonization chamber and the combustion chamber are flat structures having a height and a length that are 10 to 40 times each compared to the width, it is not easy to maintain the inside at a uniform and desirable temperature. In particular, it is said that it is extremely difficult to know and control the temperature in a closed carbonization chamber by installing sensors in a coke oven that frequently performs coal charging and coke extrusion operations. I must.

  In addition, a technique of attaching a radiation thermometer to the extrusion ram of the coke extruder and measuring the temperature distribution in the coke oven carbonization chamber length direction using the thermometer (for example, see Patent Document 1), or after completion of dry distillation There is also a technique for sequentially measuring the temperature of red hot coke discharged from the coke oven (see, for example, Patent Document 2), but since both are temperatures of the carbonization chamber wall or red hot coke exposed to the atmosphere after extrusion, there is a temperature error. There is a problem with accuracy.

Therefore, in order to reduce the disadvantages due to the non-uniform temperature in the carbonization chamber, it is considered desirable to frequently measure the temperature of the combustion chamber as a heat source at many sites and apply appropriate control.
JP 2006-265273 A JP 58-154789 A

  As described above, in order to reduce the disadvantage caused by the temperature nonuniformity in the carbonization chamber, it is desirable to frequently measure the temperature of the combustion chamber as a heat source at many sites and apply appropriate control. However, increasing the temperature measurement points and frequency leads to an increase in thermometer installation costs, manual temperature measurement costs, and automation costs, so measurements are not always performed with sufficient points. The combustion chamber temperature is constantly monitored at one representative point (in many cases, near the midpoint in the longitudinal direction of the combustion chamber), and the longitudinal temperature distribution is manually measured only when necessary. Only. One of the reasons for operating in such a situation is that a method for obtaining information about the temperature distribution of the combustion chamber and the carbonization chamber by a simple means has not been known.

  Also, it is generally not easy to adjust the temperature distribution in the carbonization chamber (and the combustion chamber that serves as its heat source). That is, normally, in a coke oven, a valve for adjusting the flow rate of fuel gas to the entire combustion chamber is installed, and it is relatively easy to adjust the average temperature of the combustion chamber. A device for controlling the distribution of the gas is not usually provided, and adjustment is performed by adjusting the opening degree of the hole provided in the gas flow path or the position of the brick, so that the temperature distribution is adjusted. It is difficult. Furthermore, when the temperature distribution of the combustion chamber is disturbed due to the damage of the brick structure accompanying the aging of the furnace body, it is not easy to repair the damaged portion. This is because once a brick whose temperature has risen is cooled, cracking occurs due to the shrinkage of the brick. Once the coke oven starts operation, it must be repaired while being heated as much as possible. Thus, since it takes a lot of labor to adjust the temperature distribution, it is important to know which kiln should be preferentially temperature-adjusted among many carbonization chambers, but it occurs in each kiln. There is no known simple method that can quantitatively evaluate the degree of abnormality of the temperature distribution.

  In view of such a current situation, a method for quantitatively estimating the temperature distribution in the carbonization chamber and the combustion chamber is provided by a simple method without making a large facility and human investment, and thus an efficient coke oven. It is an object of the present invention to provide a coke production technique with little variation in operation.

  In order to solve the above problems, the present inventors paid attention to a phenomenon in the carbonization chamber caused by the temperature distribution in the combustion chamber. That is, as a result of various investigations on the possibility of detecting abnormalities in the temperature distribution by observation, considering that the disadvantage caused by the uneven temperature distribution is directly generated based on the phenomenon in the carbonization chamber, The present invention has been completed.

That is, the features of the present invention are as follows.
(1) In a horizontal chamber type coke oven in which a plurality of carbonization chambers and combustion chambers are alternately arranged, the carbonization time in each carbonization chamber and the representative temperature of the combustion chamber that heats each carbonization chamber from both sides are measured. ,
A state of temperature distribution generated in one carbonization chamber is estimated based on a relationship between a carbonization time in each of the carbonization chambers and an average value of representative temperatures of the combustion chambers that heat the carbonization chambers from both sides. A method for estimating the temperature distribution in the coke oven carbonization chamber.
(2) The average value measured several times during the carbonization of coal in the adjacent carbonization chamber is used as the representative temperature of the combustion chamber, measured under the same conditions in each combustion chamber. Coke oven carbonization chamber temperature distribution estimation method.
Coke characterized in that coke chamber temperature adjustment is performed based on the estimated value of temperature distribution obtained using the method for estimating temperature distribution in coke oven carbonization chamber according to (3), (1) or (2). How to operate the furnace.
Using the estimation method for the temperature distribution in the coke oven carbonization chamber described in (4), (1) or (2), the temperature of the carbonization chamber is adjusted based on the obtained estimated value of the temperature distribution, and the coal in the carbonization chamber is A method for producing coke, characterized by dry distillation.

  According to the present invention, the temperature distribution in the carbonization chamber can be known by a low-cost and simple method. In addition, the coke oven can be efficiently operated. Furthermore, coke with little quality variation can be manufactured.

  Hereinafter, an embodiment of the present invention will be described.

  The present invention utilizes the fact that the carbonization state in the carbonization chamber changes with temperature. That is, dry distillation proceeds fast under high temperature conditions, and dry distillation progresses slowly under low temperature conditions. As a result, a difference occurs in the time until the end of dry distillation depending on the heating temperature. When the dry distillation is completed, the conversion reaction from coal to coke is completed, and the gas generation from the coal is almost completed. This can be used to know that the dry distillation of coal has been completed. There are several known methods for determining the end of dry distillation, and in the old days it was often judged by the color when the gas generated from coal was burned. A general method is to measure gas temperature, flow rate, and composition in a line (one for each carbonization chamber). The time from coal charging to the end of carbonization, measured in this way, is referred to herein as “carbonization time”. Note that since the end of dry distillation is sometimes referred to as “fire-off”, the term “fire-off time” is also used, but it is synonymous with “dry distillation time” used in the present invention.

  However, it is impossible to immediately know the temperature distribution in the carbonization chamber by measuring the “dry distillation time” alone. This is because the carbonization time observed in this way first shows the average state of the phenomenon in the carbonization chamber, and secondly, the carbonization time is not limited to the carbonization temperature and its distribution. This is because, since it is affected by the moisture content of the coal to be charged, the bulk density at the time of charging, the quality of the coal, etc., information on the temperature distribution cannot be obtained simply by the length of the carbonization.

  The present inventors have found that the temperature distribution of the carbonization chamber can be known by comparatively analyzing the carbonization time obtained for each carbonization chamber with the carbonization time of other carbonization chambers of the same coke oven group. Here, the coke oven group refers to a group of carbonization chambers operated under almost the same operating conditions in the operation of the coke oven (in many cases, 50 to 50 so that the same operation crew can operate efficiently). It is common to operate with the operating conditions of a carbonization chamber of about 200 kilns.) By analyzing the correlation between the carbonization time of each coking chamber of the coke oven and the typical temperature of the combustion chamber heating the coking chamber, the degree of turbulence in the temperature distribution of the coking chamber is relatively evaluated, and the information Based on this operation, coke is produced. Specifically, the temperature distribution in the carbonization chamber is estimated by this method as follows.

  First, for one carbonization chamber, the representative temperatures of the combustion chambers on both sides that heat the carbonization chamber are measured. And the carbonization time (time from coal charging to the end of carbonization) of the carbonization chamber under the conditions is obtained. Here, the time until the end of the dry distillation can be determined by a known method, but preferably, the rate of decrease in the gas temperature accompanying the decrease in the amount of gas generation is increased with the change in the gas temperature in the riser as an index. It is desirable to measure the end of dry distillation with less error. As for the representative temperature of the combustion chamber, the temperature measured at a substantially central portion in the length direction of the combustion chamber, more specifically, at a point in the range from the midpoint of the length direction of the combustion chamber to a quarter of the length of the combustion chamber. It is desirable to use Here, the position in the height direction for measuring the combustion chamber temperature is most preferably measured by embedding a thermocouple in a brick near the upper portion of the combustion chamber, but a thermocouple installed in the combustion gas flow path or a radiation thermometer The measured temperature value in the combustion chamber may be used. In any case, the temperature measurement part and the measurement method of the combustion chamber need to be measured under the same conditions in each combustion chamber, and substantially the same in each combustion chamber. However, since the temperature of the combustion chamber measured in this way changes with time even during one dry distillation operation, the typical temperature of the combustion chamber is frequently (preferably during dry distillation from charging to kiln removal). It is necessary to use the average value of the measured values (continuous measurement or at least 5 times during one dry distillation). This is because one combustion chamber is structured to heat two carbonization chambers located on both sides of the combustion chamber, so when coal is charged into the carbonization chamber adjacent to the carbonization chamber of interest, Due to heat deprivation and temperature drop, and depending on the side temperature position, combustion switching (switching combustion gas and air flow paths for effective use of heat stored in coke oven heat storage chamber) Because of the temperature fluctuation, the temperature at a certain moment alone is not sufficient to be the representative temperature of the combustion chamber.

  When plotting the carbonization time of the carbonization chambers of the plurality of kilns and the average value of the representative temperatures of the combustion chambers on both sides thereof, for example, in one day of operation, a graph as shown in FIG. 1 is obtained. The period during which such plotting is performed is preferably a period in which the raw materials and operating conditions are substantially constant, and it is more preferable to use data for one day or a period in which all the operating carbonization chambers take a round. The meaning of the regression line in this plot is the average degree of shortening of the carbonization time due to an increase in the combustion chamber representative temperature. In this method, the relative magnitude of the turbulence of the temperature distribution can be evaluated by making a comparison between the carbonization chambers under almost the same operating conditions except for the state of the carbonization chamber.

  In general, it is known that increasing the temperature of the combustion chamber shortens the carbonization time. However, if the temperature distribution in the combustion chamber is large due to aging, etc., the simple method can be used to reduce the carbonization time and combustion. It becomes difficult to obtain a good correlation between the room temperatures. The inventors have found out that the above conditions are preferable as a result of investigating which temperature is used as the representative temperature of the combustion chamber, and found that this condition is preferable. This is a major advance from the technology.

  Based on the plot of FIG. 1 obtained in this way, the temperature distribution of each carbonization chamber is estimated. That is, it can be determined that the carbonization chamber located on or near the regression line is in an average state of the furnace group. However, the carbonization chamber located on the upper side of the regression line shows that the carbonization time is required for the combustion chamber temperature, and there is a portion where the temperature is lower than the representative temperature in the carbonization chamber. It can be estimated that a dry distillation delay has occurred. On the other hand, it is presumed that there is a part having a higher temperature than the representative temperature in the carbonization chamber located below the regression line. In any case, the carbonization chamber plotted farther from the regression line is estimated to have a larger temperature distribution in the carbonization chamber, and such a carbonization chamber can be adjusted or repaired by known methods, or manual temperature control can be strengthened. If it is understood that it is necessary to carry out the operation improvement based on this information, an efficient operation of the coke oven can be achieved, and the disturbance of the coke quality due to the temperature distribution can be suppressed.

  The plot in FIG. 2 is obtained by plotting the carbonization time of the carbonization chambers of the plurality of kilns same as that in FIG. 1 and the average value of the representative temperature of the combustion chambers on both sides thereof in one day of operation. Here, the carbonization time is determined based on the decreasing tendency of the temperature measured in the riser section, and the combustion chamber representative temperature is embedded in the brick near the upper portion of the combustion chamber space in the center in the combustion chamber length direction. It is the average value over the carbonization time of the temperature measured using the measured thermocouple, and the average of the representative temperatures of the combustion chambers on both sides of the carbonization chamber is plotted on the horizontal axis.

  FIG. 3 shows the temperature distribution in the longitudinal direction of the combustion chambers on both sides of the carbonization chamber indicated by point A in FIG. This temperature is measured manually from a plurality of inspection ports (1 to 17) installed in the upper part of the combustion chamber using a radiation thermometer. Therefore, the value of the thermocouple installed to obtain the representative temperature is obtained. Higher temperature. In general, the carbonization chamber has a larger coke outlet side (CS) than the side where the extruder is installed (PS), so the amount of coal is higher in the vicinity of CS and the temperature of the combustion chamber is set higher. However, the temperature distribution in FIG. 3 is in the normal range. Moreover, although the temperature near the both ends of the combustion chamber is slightly lowered due to heat radiation, it is still in a normal range.

  In contrast, FIGS. 4 and 5 show temperature distributions similarly measured in the carbonization chambers at points B and C in FIG. In the carbonization chamber at point B, the temperature drop at the end is greater than at the center of the combustion chamber. That is, it can be seen that the temperature distribution is disturbed compared to the normal temperature distribution (in the case of FIG. 3). Conversely, at the point C, the temperature in the center of the combustion chamber has decreased. For confirmation, a thermocouple was inserted between the center of the carbonization chamber and the vicinity of the furnace lid, and the temperature of the coke layer at the end of dry distillation was measured. In the carbonization chamber A, the temperature difference between the center and the furnace lid was 100 ° C. On the other hand, in the carbonization chamber at point B, the temperature difference was 260 ° C., and the variation in temperature distribution was large. In this manner, it is possible to determine which carbonization chamber and the temperature distribution of the combustion chamber serving as its heat source are abnormal from the plot of FIG.

  Ten samples of coke were sampled from coke produced in the carbonization chamber A and the carbonization chamber B in FIG. 2, and the coke strength (DI150 / 15) of each sample was measured by the JIS method. At this time, the average intensity was almost equal to 84.0 for A and 84.1 for B, but the range of variation in the measured value from the highest value to the lowest value among the 10 samples was 0.6 for A. Whereas B was 1.1. From this, it can be seen that the coke sample produced in the carbonization chamber with a disturbed temperature distribution has a large variation in strength. In addition, after adjusting the temperature distribution of the carbonization chamber of B at a later date by replacing the nozzle plate (parts for controlling fuel gas distribution), the same sampling was performed again, and the strength was measured. The range of variation was 0.5, and the variation in coke strength was also improved by improving the temperature distribution.

The graph which shows the average relationship between dry distillation time and a combustion chamber typical temperature. The graph which shows the average relationship between dry distillation time and a combustion chamber typical temperature. The graph which shows the length direction temperature distribution of the combustion chamber in the carbonization chamber with a normal temperature distribution. The graph which shows the length direction temperature distribution of the combustion chamber in the carbonization chamber (B) with abnormal temperature distribution. The graph which shows the length direction temperature distribution of the combustion chamber in the carbonization chamber (C) with abnormal temperature distribution.

Claims (3)

In a horizontal chamber furnace type coke oven in which a plurality of carbonization chambers and combustion chambers are alternately arranged,
While measuring the carbonization time in each carbonization chamber ,
The temperature of each combustion chamber that heats each carbonization chamber from both sides is measured a plurality of times during the dry distillation of coal in each carbonization chamber under the same conditions in each combustion chamber, and the average value of the measured temperatures is measured for each combustion Used as a typical room temperature,
The measured dry distillation time on the vertical axis, to create a graph plotted on the horizontal axis the average of the representative temperature of the combustion chamber on both sides of the carbonization chamber wherein the drying distillation time is measured,
From the graph, create a regression line representing the carbonization time as an average value of the representative temperature,
The carbonization chamber located on or near the regression line is determined to be in the average state of the furnace group (hereinafter referred to as point A),
The carbonization chamber located on the upper side of the regression line is determined to have a portion having a temperature lower than the representative temperature in the carbonization chamber (hereinafter referred to as point B),
The carbonization chamber located below the regression line was generated in one carbonization chamber by determining that a portion having a temperature higher than the representative temperature exists in the carbonization chamber (hereinafter referred to as point C) . estimation method for a coke oven carbonization chamber temperature distribution, characterized in that to estimate the state of the temperature distribution. Using the method for estimating the temperature distribution in the coke oven carbonization chamber according to claim 1, estimating the temperature distribution in the coking chamber,
A method for operating a coke oven, wherein the temperature of the carbonization chambers at points B and C is adjusted so that the temperature distribution of the carbonization chambers at points B and C becomes the temperature distribution at point A. Using the method for estimating the temperature distribution in the coke oven carbonization chamber according to claim 1, estimating the temperature distribution in the coking chamber,
The coke is characterized in that the temperature in the carbonization chamber at point B and C is adjusted so that the temperature distribution in the carbonization chamber at point B and C is the temperature distribution at point A, and the coal in the carbonization chamber is carbonized. Production method.

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