JPH11116964A - Method for removing adhering carbon in coke oven carbonization chamber - Google Patents

Abstract

(57) Abstract: The present invention prevents unnecessary overheating and supercooling of a carbonization chamber, thereby preventing damage to a refractory of a furnace wall and joints, and leaving carbon adhered to the joints. It is an object of the present invention to provide a method for removing adhering carbon in a coke oven charcoal chamber, in which carbon adhering to other parts is reliably removed in a state where the carbon is stuck. SOLUTION: When spraying an oxygen-containing gas from a nozzle inserted into a carbonization chamber to a carbon attached to a carbonization chamber of a coke oven to burn and remove the oxygen-containing gas, the oxygen concentration of the gas is determined by:
Change according to the layer thickness and combustion characteristics of the attached carbon,
Blow the gas.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of operating a coke oven furnace, and more particularly to a technique for removing carbon adhering to a coking chamber.

[0002]

2. Description of the Related Art A carbonization chamber of a coke oven is filled with a hydrocarbon gas containing tar generated in a carbonization process of coal, and this gas is thermally decomposed on a brick surface in a furnace at a high temperature. Generates carbon. This carbon penetrates and grows in pores, joints, or defective portions generated by spalling or the like in the furnace wall brick in the carbonization chamber, and forms a strong adhesion layer. If this carbon layer is left unattended, the coke cake after the dry distillation is pushed out of the carbonization chamber,
The frictional resistance between the coke cake and the carbon layer increases, and if the frictional resistance is remarkable, it becomes impossible to extrude the so-called "clogging". For this reason, in the daily operation of a coke oven, air is periodically blown into the carbonization chamber to remove the carbon layer. However,
In this removal operation, the carbon burns to generate a local high-temperature portion on the furnace wall, and also causes a temperature decrease in the vicinity of the door, which is an air intrusion portion, and a large heat load (overheating or overheating) on the furnace wall brick. Cooling, which caused damage to the furnace body and was regarded as "necessary evil" for coke oven operation.

[0003] As a technique to solve such a situation,
"There is a method in which a plurality of nozzles are inserted into a carbonization chamber, and an oxygen-containing gas is sprayed only at a required position to burn and remove the carbon layer attached thereto. It is difficult to completely remove the mottled carbon, and in some cases, there is a drawback in that it is over-burned and carbon even as joints of the furnace wall brick is removed.

Therefore, Japanese Patent Publication No. Hei 7-91541 discloses that
A method for partially changing the injection condition of the injection gas according to the thickness of the carbon layer was proposed. However, the deposited carbon greatly varies not only in layer thickness but also in properties depending on the location of the coke oven, and thus, in this method, too much carbon is overburned as described above. Japanese Patent Application Laid-Open No. 6-2 / 1994 discloses a combustion and removal method focused on carbon properties.
Japanese Patent No. 48272 discloses that "carbon adhering near a raw coal charging hole is blown off by high-pressure air, and carbon adhering to a furnace wall is burned and removed by air or the like from a low-pressure nozzle."
A method is disclosed. However, in this method, a difference occurs in the amount of air (oxygen) blown to the vicinity of the charging hole and the furnace wall, and carbon near the charging hole is excessively dropped, but the combustibility attached to the furnace wall is low. There is a problem that carbon cannot be sufficiently burned and removed.

[0005]

SUMMARY OF THE INVENTION In view of such circumstances, the present invention prevents unnecessary heating and supercooling of a carbonization chamber, thereby preventing damage to a refractory of a furnace wall and joints, and adhering to the joints. It is an object of the present invention to provide a method for removing adhering carbon in a coke oven charcoal chamber in which carbon adhering to other portions is surely removed with the remaining carbon remaining.

[0006]

Means for Solving the Problems In order to achieve the above object, the inventor investigated the state of adhesion of carbon in the carbonization chamber and reviewed the prior art as described below.
The temperature in the coke oven carbonization chamber is not uniform and ranges from about 50 to 1 from the so-called coke side (the side where the coke cake is extruded) to the machine side (the side where the extruder is installed).
There is a temperature gradient of 00 ° C, and about 20 ~
There is a difference of 80 ° C. In general, the growth rate of carbon deposited in the carbonization chamber is affected by the temperature of the furnace wall, the volatile content of the charged coal, moisture, the flow rate and flow rate of the gas in the furnace, and the like. Is not expected to be uniform. Ideally, the deposited carbon is desirably deposited uniformly on the entire inner wall and ceiling of the furnace and thin enough to replenish the sealing function of the brick joint.

[0007] The inventor conducted an investigation of the distribution of the amount of carbon deposited in the carbonization chamber and the combustion of carbon deposited in various parts of the chamber. As a result, it was confirmed that the distribution of the amount of carbon was as expected as shown in FIG. On the other hand, in order to investigate the combustion characteristics of these carbons having different adhesion states, samples were taken at different positions in the room. After shaping the sample and heating it to 800 ° C. in an electric furnace, the results of a combustion experiment performed by blowing an oxygen-containing gas from one direction showed that the carbon burning rate of each sample was as shown in FIG. It was shown that there was a large difference depending on the sampling position. That is, the sample taken in the thin region (symbol A) of the carbon layer has a low burning rate, while the sample taken in the thick region (symbol B) has a high burning rate. This is because each carbon layer is subjected to various heat histories and forces in the furnace, and specifically, the apparent density (density) and the carbon content of the carbon layers are different.

Further, the inventor has found that in these combustion experiments, the burning speed of each sample increases with the oxygen concentration of the injected gas (see FIG. 2), and as shown in FIG. It was confirmed that it increased with the amount of air blown. Therefore, the inventor reviewed the conventional method for removing adhering carbon based on the results of the above investigations and experiments, and set the conditions of the blowing gas necessary for combustion appropriately, taking into account not only the layer thickness but also the combustion characteristics. It was thought that the combustion could be performed in the carbonization chamber so that the thickness of the carbon layer would be uniform.

[0009] The present invention embodies this idea, and sprays an oxygen-containing gas from a nozzle inserted into a carbonization chamber of carbon adhering to the carbonization chamber of a coke oven to burn and remove the gas. The method according to claim 1, wherein the oxygen concentration is changed according to the thickness of the deposited carbon and the combustion characteristics, and then the gas is blown to remove the deposited carbon in the coke oven carbonization chamber.

[0010] The present invention also provides an oxygen-containing gas blown from a nozzle inserted into a coking chamber to the carbon adhering to the carbonization chamber of the coke oven to burn and remove the gas. A method for removing carbon deposits in a coke oven carbonization chamber, characterized in that the gas is blown while changing according to the layer thickness and combustion characteristics of the coke oven.

In the present invention, the carbon adhering to the coke oven carbonization chamber is burned and removed by the above-described method, so that a necessary portion can be burned and removed under appropriate conditions. As a result, unnecessary overheating and overcooling of the carbonization chamber, and damage to the refractory of the furnace wall and joints due to this can be prevented.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In carrying out the present invention, it is necessary to know in advance the distribution of the amount of deposited carbon as shown in FIG. 1 and the combustion characteristics of the carbon layers existing in the respective regions A, B and C. . In consideration of these two conditions, it is determined under what conditions (in the present invention, the oxygen concentration and the flow rate of the blowing gas) the combustion in each region is performed, and the oxygen-containing gas is blown according to the conditions.

Specifically, the distribution of the amount of deposited carbon can be determined by various methods, for example, by measuring the change in the room temperature of a coke oven using a room temperature measuring instrument. It can be obtained by using the accumulated data of the combustion experiment results of the sample. Then, the combustion conditions are determined in consideration of the combustion characteristics in the attached amount distribution as follows.

(T _A / R _A ) = (T _B / R _B ) = (T _C
/ R _C ) = constant. _{Here, T A, T B, T} C: Coke A, B, thickness _{C (mm) R A, R} B, R C: Coke A, B, the burning rate of C (m
m / min) In the present invention, the oxygen concentration of the oxygen-containing gas blown from the nozzle to the carbon layer while changing the nozzle position in each region based on the combustion conditions determined in this way (Invention 1)
Alternatively, the carbon layer is burned by changing the flow rate (Invention 2). At this time, the temperature of the deposited carbon in the furnace is 800 ° C. or higher, and sufficient combustion of carbon occurs even if a normal-temperature gas is blown. In the present invention,
In order to minimize the burning of carbon on joints between bricks, the burning time is determined so that the carbon layer thickness after burning becomes 1 mm.

The method for removing carbon according to the present invention was carried out in a carbonization chamber having the carbon deposition amount distribution shown in FIG. 1, and the results are shown in Tables 1 and 2. Here, Table 1
Table 2 shows the results of the invention in which the oxygen concentration of the blowing gas is changed, and Table 2 shows the results of the invention in which the flow rate of the gas is changed. In addition, Tables 1 and 2 show the conventional cases where “the oxygen-containing gas having a constant oxygen concentration is simply blown into the carbonization chamber at a constant flow rate” and “when only the thickness distribution is considered”. Are also shown. In addition, the carbon thickness after combustion shown in Table 1 and Table 2 is an average value of carbon thickness actually measured at 15 places in the carbonization chamber after burning carbon in each case.

[0016]

[Table 1]

[0017]

[Table 2]

From any of the tables, it can be seen that the application of the carbon removing method according to the present invention makes the adhesion of carbon uniform and thin over the entire inner wall of the furnace, and its effectiveness is higher than other methods. it is obvious. Furthermore, the time required to carry out the carbon removing method according to the present invention was less than 10 minutes, which was able to be reduced by about 30% as compared with the conventional example and the comparative example. Also,
The electric power at the time of coke extrusion was reduced by about 20% as compared with the conventional case, and a smooth and stable operation of the coke oven became possible.

[0019]

As described above, according to the present invention, it is possible to burn and remove carbon so as to remain thin and uniform in each part in the coke oven carbonization chamber. Further, according to the present invention, there is no occurrence of damage due to local supercooling of the furnace body or remaining due to uneven combustion of carbon.
Furthermore, carbon removal work can be performed more efficiently in a shorter time than before, and as a result, it is expected to greatly contribute to solving the problems of productivity reduction and acceleration of furnace body damage due to carbon adhesion trouble. .

[Brief description of the drawings]

FIG. 1 is a side view showing a distribution example of an amount of carbon attached to a wall surface of a coke oven carbonization chamber.

FIG. 2 is a diagram showing the relationship between the burning rate and oxygen concentration of a sample collected from adhered carbon.

FIG. 3 is a diagram showing the relationship between the burning rate of a sample collected from adhered carbon and the flow rate of blowing gas.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Coalization room 2 Ceiling 3 Charcoal charging port 4 Furnace gas riser 5 Door

Claims (2)

[Claims] 1. An oxygen-containing gas is blown from a nozzle inserted into a carbonization chamber to a carbon attached to a carbonization chamber of a coke oven to burn and remove the oxygen-containing gas. A method for removing adhering carbon in a coke oven carbonization chamber, wherein the gas is blown after changing according to combustion characteristics. 2. An oxygen-containing gas is blown from a nozzle inserted into the carbonization chamber onto the carbon deposited in the coke oven carbonization chamber to burn and remove the oxygen-containing gas. A method for removing adhering carbon in a coke oven carbonization chamber, wherein the gas is blown after changing according to combustion characteristics.