JPH10168456A - Method for managing temperature of end flue of coke oven - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect abnormal combustion early by quickly detecting a change in the temperature in an end flue. SOLUTION: A thermocouple is inserted into an area at or near the center of an opening formed in a duct which connects an end flue to a regenerator or a horizontal crossroad and situated on the side of the regenerator or the crossroad. The temperature in the atmosphere in the opening on the side of the regenerator or the crossroad is measured. The end flue upper atmosphere temperature Y is determined by using the measured temperature and the predetermined formula: Y=aX+b (a is a coefficient, b is a constant; and X is the temperature of the atmosphere in the opening situated on the side of the regenerator or the crossroad).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling the temperature of an end flu of a coke oven having a large number of combustion chambers.

[0002]

2. Description of the Related Art In a coke oven furnace, a heat storage chamber is provided at a lower portion of a furnace body, and a combustion chamber and a carbonization chamber are alternately arranged above the furnace. Heating of the charged coal in the coking chamber is performed from a combustion chamber consisting of about twenty to thirty flew adjacent via a furnace wall brick. Combustion management of a coke oven is one of the most important tasks from the viewpoint of stabilizing coke quality, reducing calorific value, stabilizing the furnace operation, and preventing damage to the furnace body.
For furnace temperature control, maintain the temperature level of the entire furnace group stably at a temperature corresponding to the operation rate, and properly adjust the temperature distribution in the furnace length, furnace height, and furnace group direction so that coal carbonization proceeds uniformly. It is important to maintain.

[0003] Regarding the temperature distribution in the furnace length direction of the combustion chamber,
The temperature is controlled so as to have a temperature gradient of usually 12 to 15 ° C. per 10 mm of the furnace width along the taper of the furnace width of the coking chamber. However, the end flues on the coke side and the machine side do not have the above-mentioned temperature gradient due to heat loss such as heat dissipation from the furnace end to the outside air and cooling due to contact with the outside air at the furnace opening when the furnace lid is removed. Although it is general and varies depending on the type of coke oven or the like, as shown in FIG. 6, it is common that both ends are lower by about 50 to 150 ° C. than the reference temperature gradient.

[0004] Each flue constituting the combustion chamber is switched by combustion switching for a predetermined time, for example, every 15 to 30 minutes.
The combustion flues are switched to exhaust flues, and the exhaust flues are switched to combustion flues, so that the entire coke oven is heated uniformly. The temperature of flue switched from exhaust to combustion by combustion switching increases with time, but the temperature of flue switched from combustion to exhaust generally decreases with time.

On the other hand, since the combustion chamber is generally made of silica brick mainly composed of SiO ₂ , the end flue on the machine side showing the lowest temperature among the flues constituting the combustion chamber is usually 900 ° C. or more. The temperature of the combustion chamber is controlled so as to maintain the temperature. This is because the SiO ₂ transformation point, which is the main component of the silica brick, is 870 ° C.
When the temperature drops below ℃, the shrinkage of the silica brick increases and the joints of the bricks open, the confidentiality of the carbonization chamber is lost, and the generated gas leaks from the carbonization chamber into the combustion chamber, causing various operational problems such as black smoke generation due to incomplete combustion. Is to be invited.

As a method of controlling the temperature of the combustion chamber of the coke oven, a temperature distribution and a target temperature distribution of the coke oven measured by a temperature sensor installed in a representative flue row of the coke oven to detect a temperature distribution in a furnace length direction are measured. In general, a method of comparing and managing is used. However, in this method, the installed thermocouple not only hinders normal on-furnace work, but also requires quick removal, such as the necessity of removing the thermocouple for inspection when abnormality inside the combustion chamber is suspected. It does not interfere with the treatment. Further, from the viewpoint of early detection of an abnormality inside the combustion chamber, since the ambient temperature at the upper part of the combustion chamber is measured, there is a drawback that the followability is poor.

As another method, as shown in FIG. 7, a thermocouple 73 is embedded in a refractory 72 on the back side of a back stay 71 at a furnace end to measure a temperature, and based on the temperature, a thermocouple 74 is formed. A method of estimating the combustion temperature and controlling the combustion to control the temperature of the end flu (Japanese Patent Laid-Open No.
No. 135485) has been proposed.

[0008]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Application Laid-Open No. 63-13 / 1988
The method disclosed in Japanese Patent No. 5485 can detect a combustion abnormality only when the internal temperature of the refractory on the back side of the backstay changes, and since the internal temperature of the refractory does not change immediately even if a combustion abnormality occurs, There is still a problem of lack of speed.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks of the prior art, to enable monitoring of the temperature of the end flute without disturbing the on-furnace work, and to quickly detect a temperature change in the event of abnormal combustion. It is an object of the present invention to provide a method for controlling the temperature of the coke oven flu, which can be performed and does not hinder the inspection of the inside of the flu.

[0010]

According to a first aspect of the present invention, there is provided a method for controlling the temperature of an end flue, comprising: a duct connecting the end flue with a heat storage chamber or a horizontal intersection; By the thermocouple inserted near,
The ambient temperature of the opening of the duct on the side of the heat storage chamber or the horizontal road is measured, and based on the measured temperature, the ambient temperature Y at the end flew is determined and managed by the following formula (1). Y = aX + b (1) where a: coefficient, b: constant, and X: the ambient temperature of the heat storage chamber of the duct or the opening of the horizontal intersection.

As described above, the thermocouple inserted on the side of the heat storage chamber of the duct connecting the end flue and the heat storage chamber or on the side of the horizontal path of the duct connecting the end flue and the horizontal crossing can be used. By measuring the ambient temperature of the opening at the traffic road side and obtaining and managing the end flue upper temperature Y by the above-mentioned formula (1) based on the measured temperature, the temperature control of the combustion chamber at the end flue can be quickly performed. Can be done.

According to a second aspect of the present invention, there is provided a method for controlling the temperature of an end flue, wherein the thermoelectric device is inserted at or near the center of the opening on the side of the heat storage chamber or on the side of the horizontal intersection on the duct connecting the end flue with the heat storage chamber or the horizontal intersection. The pair is used to measure the ambient temperature of the opening on the side of the heat storage chamber or on the side of the horizontal intersection, and determine the temperature difference (ΔT) when switching from combustion to exhaust and exhaust to combustion at the measured ambient temperature of the opening. If the control value falls below the control value, the end flute is determined to be abnormal combustion and an alarm is output.

As described above, the thermocouple inserted at the center or near the opening of the duct connecting the end flue and the heat storage chamber or on the side of the horizontal crossing of the duct connecting the end flue and the horizontal intersection has the duct. Measurement of the opening ambient temperature on the side of the heat storage chamber or the horizontal intersection, and the temperature difference (ΔT) at the time of switching from combustion to exhaust and exhaust to combustion at the measured opening ambient temperature is equal to or less than a preset control value. In this case, the end flew is determined to be abnormal combustion and an alarm is output, so that the operator can be notified of the abnormal end flue early.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a Coppers-type double coke oven having a horizontal passageway at an intermediate portion between a heat storage chamber and a combustion chamber, a duct which communicates the end flew with the heat storage chamber or the end flew and the horizontal passageway has a horizontal passageway or a horizontal passageway. If a thermocouple is inserted at the center of the opening on the roadway side or in the vicinity of the opening, the ambient temperature of the opening on the heat storage room side or the horizontal roadway side of the duct can be continuously measured. In other types of coke ovens that do not have a horizontal path in the middle between the heat storage chamber and the combustion chamber, a thermocouple is inserted at or near the center of the opening on the heat storage chamber side of the duct that communicates the end flute with the heat storage chamber. This makes it possible to continuously measure the ambient temperature of the opening of the duct on the heat storage chamber side.

The end flu in the present invention is, for example, 1
# 1 in a combustion chamber composed of up to 30 flew
Flue and # 30 flue are end flues. For example, a thermocouple is placed at or near the center of the opening on the side of the heat storage chamber or on the horizontal crossing side of the duct connecting the # 1 flue with the heat storage chamber or the duct connecting the # 30 flue with the horizontal crossing. insert. And
For example, at the time of # 1 flue combustion, # 30 flue is on the exhaust side, and the center of the opening on the side of the heat storage chamber or the horizontal crossway of the duct communicating between # 1 flue and the heat storage chamber or # 30 flue and the horizontal intersection. Atmospheric temperature near the opening is detected, and during # 30 flue combustion, the center or opening of the duct on the heat storage chamber side or horizontal crossing side of the duct connecting the # 1 flue on the exhaust side and the heat storage chamber or the # 30 flue and the horizontal intersection. Detect nearby ambient temperature.

In the end flew, the lowest value of the ambient temperature above the end flew, that is, the ambient temperature above the end flew at the time of switching from exhaust to combustion, and a duct for communicating the end flew with the horizontal intersection or the end flew and the heat storage chamber. If the relationship between the center of the opening on the horizontal traffic path side or the heat storage room side and the ambient temperature near the opening is determined in advance, the opening on the horizontal traffic road side or the heat storage chamber side of the duct connecting the end flute and the horizontal traffic path or the heat storage chamber The ambient temperature above the end flute can be estimated from the ambient temperature near the center or the opening. For example, FIG. 4 shows a horizontal intersection of a duct connecting the end flew and a horizontal intersection with an ambient temperature above the end flew at the time of switching from the exhaust to the combustion of the Coppers double furnace having a furnace height of 7125 mm, a furnace width of 460 mm, and a furnace length of 16500 mm. An example of the relationship with the ambient temperature near the opening on the side is shown. In FIG.
The n number is 50 and the correlation coefficient is 0.525.

In order to manage the end flue temperature, the ambient temperature Y above the end flue is obtained from the relationship between the ambient temperature near the opening on the horizontal intersection side of the duct and the atmosphere temperature Y above the end flue by the following equation (1). , The atmosphere temperature Y above the end flute is controlled to a predetermined value, for example, 900 ° C. or more. Y = aX + b (1) where a: coefficient, b: constant, and X: the ambient temperature of the heat storage chamber of the duct or the opening of the horizontal intersection. For example, FIG.
, The coefficient a = 1.137 and the constant b = −228.
It becomes 8. Since the coefficient a and the constant b vary depending on the type, size, operating conditions, and the like of the furnace, they may be determined in advance for each furnace based on operation results and the like.

From the above results, a thermocouple is inserted and installed at the center of the opening on the side of the heat storage chamber or on the side of the horizontal traffic path or near the opening of the duct connecting the end flute and the heat storage chamber or horizontal traffic path,
Measuring the ambient temperature, ie, the temperature of the exhaust gas from the end flute or the temperature of the fuel gas and combustion air, can be used as an alternative to the measurement of the atmosphere temperature above the end flute. In addition, a thermocouple is inserted and installed at the center of the opening on the heat storage chamber side or horizontal intersection side or near the opening of the duct connecting the end flues with the heat storage chamber or horizontal intersection, and the temperature of the exhaust gas from the end flues or fuel gas and combustion Measure the air temperature, insert a thermocouple through the inspection hole at the top of the end flute, and measure the ambient temperature at the top of the end flute.
As shown in FIG. 5, the pattern of the ambient temperature above the end flute increases with the passage of time when switching from exhaust to combustion, but decreases with the passage of time when switching from combustion to exhaust. On the other hand, the pattern of the ambient temperature at the horizontal passage side opening of the duct, when switched from exhaust to combustion, decreases over time due to the passage of fuel gas or combustion air, and conversely, is switched from combustion to exhaust. As the combustion exhaust gas passes, it rises with the passage of time.

As described above, in the normal operation, the switching of the combustion chamber from the combustion to the exhaust and the exhaust to the combustion is repeatedly performed at regular intervals, and the temperature difference is in the range of about 100 to 150 ° C. Therefore, the combustion exhaust gas always passes through the duct that connects the end flute and the heat storage chamber or the duct that connects the end flute and the horizontal intersection. By installing a pair and determining the temperature difference (ΔT) at the time of switching from combustion at ambient temperature to exhaust and from exhaust to combustion, and comparing it with a preset control value, it is possible to quickly grasp the combustion state of end flew. If it is less than the control value, it is determined that the combustion is abnormal, and if an alarm is output, the operator can be notified of the abnormal combustion of the end flew at an early stage.

[0020]

【Example】

Example 1 Furnace height 7125 mm, furnace width 460 mm, furnace length 16500 m
m coppers double furnace, the method of the present invention is shown in FIG.
As shown in (1), a thermocouple 4 was inserted and installed in the vicinity of the opening on the side of the horizontal intersection 2 of the duct 3 that communicates the cork side end flue 1 (# 30 flue) with the horizontal intersections 2 and 2. For comparison, a thermocouple was inserted and installed from the furnace inspection hole of the cork side end flu 1 (# 30 flu) as a conventional method. Then, the air port 5 and the poor gas port 6 of the end flu 1 (# 30 flu) are closed using a brick, and the air port 5 and the poor gas port 6 are clogged, so that the fuel gas and the combustion air do not flow in the same manner. The state was reproduced, and the temperature of end flute 1 was lowered. The temperature of the end flute 1 in this case is shown in FIG. 2 with A being the upper atmosphere and B being the atmosphere near the opening of the duct 3 on the side of the horizontal intersection 2. For comparison, the result of measuring the temperature change of the combustion port of the same end flute 1 from the inspection hole on the furnace with a radiation thermometer is shown as C in FIG. In FIG. 1, reference numeral 7 denotes a heat storage chamber, 8 denotes a carbonization chamber, and 9 denotes a combustion chamber.

As shown in FIG. 2, a remarkable temperature drop (ΔT) is apparently caused by the stoppage of the gas. However, the duct 3 connecting the end flute 1 and the horizontal intersection 2 has an opening near the horizontal intersection 2 side. In the waveform B of the thermocouple of the present invention inserted and installed, the temperature difference due to normal combustion switching is about 100 to 150.
Although it is about ° C., it is clearly apparent that the temperature difference almost disappeared by stopping the gas. On the other hand, in the waveform A of the thermocouple above the end flute in the conventional method, the temperature change due to the gas stop is not remarkably shown as compared with the waveform B of the present invention. Therefore, the method of the present invention is effective for quickly detecting a change in the temperature of the end flute.

Example 2 At the coke side end flue (# 30 flue) of a Coppers double furnace with the same furnace height of 7125 mm, furnace width of 460 mm and furnace length of 16500 mm as in Example 1, the combustion port was clogged with foreign matter and abnormal combustion occurred. FIG. 3 shows a temperature change in the case of incomplete combustion. In FIG. 3, A is the upper ambient temperature of the end flew, B is the ambient temperature near the opening on the horizontal crossing side of the duct connecting the end flew and the horizontal intersection, and C is the temperature change of the combustion port of the end flew. It is the result measured by the radiation thermometer from the inspection hole on the furnace. As shown in FIG. 3, even when switching from exhaust to combustion, the temperature of the end flute is reduced without increasing, and thereafter, when switching from combustion to exhaust, the temperature of the end flute further decreases. In this way, by obtaining the temperature difference ΔT ′ after the combustion switching, when a predetermined control value, for example, a temperature difference ΔT ′ of the end flute of 30 ° C. or less is detected, if an alarm is output, the operator is notified of the end difference. The flue combustion abnormality can be notified at an early stage.

[0023]

According to a first aspect of the present invention, there is provided a method for controlling the temperature of an end flue, the method comprising the steps of: connecting the end flue to a heat storage chamber; Using the inserted thermocouple, the ambient temperature of the opening of the duct on the side of the heat storage chamber or on the side of the horizontal intersection is measured, and based on the measured temperature, the end flue upper temperature Y is obtained and managed according to the above-mentioned equation (1). By doing
It is possible to quickly control the temperature of the combustion chamber at the end flew.

According to a second aspect of the present invention, there is provided a method for controlling the temperature of an end flue, wherein the duct connects the end flue with the heat storage chamber or the duct which connects the end flue with the horizontal intersection has a horizontal intersection. Using the inserted thermocouple, measure the ambient temperature of the opening on the side of the heat storage chamber of the duct or on the side of the horizontal intersection, and find the temperature difference (ΔT) when switching from combustion to exhaust and from exhaust to combustion at the measured ambient temperature of the opening. If the value becomes equal to or less than a preset management value, it is determined that the end flew combustion is abnormal, and an alarm is output, whereby the end flew combustion abnormality can be detected early and notified to the operator.

[Brief description of the drawings]

FIG. 1 shows a case in which a thermocouple is installed on a horizontal intersection side of a duct connecting an end flute and a horizontal intersection in the method of the present invention in Example 1, wherein FIG. 1A is a schematic front view, and FIG. The figure is a schematic perspective view showing the installation of thermocouples on the horizontal road.

FIG. 2 is a graph showing combustion of end flues, an exhaust timing, and a temperature change of each part before and after gas stop in the first embodiment.

FIG. 3 is a graph showing combustion of end flues, exhaust timing, and temperature changes of respective parts before and after port clogging in a second embodiment.

FIG. 4 is a graph showing an example of a relationship between an upper temperature of an end flute and a horizontal intersection temperature.

FIG. 5 is a graph showing an example of changes in end flue combustion and exhaust timing, an upper temperature of the end flew, and a horizontal intersection temperature.

FIG. 6 is a graph showing an example of a flue temperature gradient in a furnace length direction.

FIG. 7 is a plan view of the end flues for explaining the temperature control method of the end flues disclosed in Japanese Patent Application Laid-Open No. 63-135485.

[Explanation of symbols]

 1, 74 end flue 2 horizontal intersection 3 duct 4, 73 thermocouple 5 air port 6 poor gas port 7 heat storage room 8 carbonization room 9 combustion chamber 71 back stay 72 refractory

Claims (2)

[Claims] In a method for controlling the temperature of a coke oven end flue, a thermocouple inserted into or near a center of an opening on a regenerator side or a horizontal traverse side of a duct communicating the end flue with a heat storage chamber or a horizontal intersection is provided. A coke oven end characterized by measuring an ambient temperature of an opening at a side of a heat storage room or a side of a horizontal road, and obtaining and managing an ambient temperature Y at an end flew based on the measured temperature according to the following equation (1). Flue temperature management method. Y = aX + b (1) where a: coefficient, b: constant, and X: the ambient temperature of the heat storage chamber of the duct or the opening of the horizontal intersection. 2. A method for controlling the temperature of a coke oven end flute according to claim 1, wherein said heat storage means includes a thermocouple inserted at a center or in the vicinity of an opening of a duct connecting said end flute and a heat storage chamber or a horizontal intersection. The ambient temperature of the opening on the room side or the horizontal road side is measured, and the temperature difference (ΔT) at the time of switching from combustion to exhaust and from exhaust to combustion at the measured ambient temperature of the opening is obtained. A method for controlling the temperature of a coke oven flu, wherein the flu is determined to be abnormal combustion and an alarm is output.