JP2023049297A - Coke oven and method for supplying fuel gas to coke oven, and production method of coke - Google Patents

Abstract

To provide a coke oven and a method for supplying fuel gas to the coke oven, and a production method of coke which can increase a temperature of an end flue with a simple structure.SOLUTION: A coke oven includes: a combustion chamber which is configured to include a plurality of flues in an oven width direction to which poor gas or rich gas and combustion air are supplied for combustion; a heat storage chamber through which the poor gas, the combustion air, and exhaust gas after the combustion in the combustion chamber pass and in which the poor gas and the combustion air is preheated with heat of the exhaust gas; and a rich gas horizontal flue which is provided below the combustion chamber so as to extend in the oven width direction and which leads the rich gas to each of the flues. The coke oven is additionally provided with: a bypass line for introducing the poor gas into the rich gas horizontal flue from a poor gas line for supplying the poor gas to the heat storage chamber without passing through the heat storage chamber; and a nozzle for supplying the poor gas introduced from the bypass line to any of the flues.SELECTED DRAWING: Figure 2

Description

The present invention relates to a coke oven, a method of supplying fuel gas to the coke oven, and a method of producing coke.

2. Description of the Related Art A coke oven that carbonizes coal to produce coke is configured by alternately arranging combustion chambers for burning fuel and carbonization chambers for carbonizing charged coal. In addition, a heat storage chamber is arranged below the combustion chamber for reusing combustion exhaust heat.

The coke oven includes a single furnace that uses only coke oven gas (C gas), which is rich gas, as fuel gas, and a blast furnace gas (B gas), which is poor gas, or B gas and C gas in addition to C gas. There is a double furnace that also uses a mixed gas (M gas) of

After the combustion in the combustion chamber of the coke oven, the heat of the exhaust gas is recovered in the heat storage chamber. By preheating the lean gas and air in this heat storage chamber, the exhaust heat of the combustion gas is effectively used. The rich gas (C gas) contains a large amount of hydrocarbon gas, and if it is kept at a high temperature by passing through the heat storage chamber, it may decompose and generate soot, so it is usually burned without preheating. .

The flow of combustion gas in a Carl steel type coke oven 1, which is an example of a double coke oven, will be described with reference to FIG.

First, during lean gas combustion, the M gas and air supplied from the M gas line 50 are separately introduced from the heat valve 11 into the lower horizontal flue 12, preheated in the heat storage chamber 13, and then merged in the combustion chamber 15. are mixed and combusted. Specifically, the combustion chamber 15 is divided into, for example, 35 small chambers called flues 150 . Then, the M gas and air preheated in the heat storage chamber 13 are supplied into the flue 150 from a plurality of heights on the side surface of each flue 150, mixed with each other, and combusted.

As shown in FIG. 1, in the Carl-Steel coke oven 1, the heat storage chamber 13 and the combustion chamber 15 are each partitioned into approximately half in the width direction of the oven. Then, the M gas and air are supplied to the flue 150, which is half of the combustion chamber 15, for combustion. The exhaust gas after combustion flows from each flue 150 through the upper horizontal flue 16 provided above the combustion chamber 15 to the flue 150 in the remaining half of the combustion chamber 15 . In this way, the M-gas and air are supplied to the heat valve 11, the lower horizontal flue 12, the regenerator 13, the flue 150 in one half of the combustion chamber 15, the upper horizontal flue 16, the flue 150 in the other half of the combustion chamber 15, It flows through a heat storage chamber 13 on the opposite side, a lower horizontal flue 12 on the opposite side, a heat valve 11 on the opposite side, and into a chimney (not shown). Then, the flue 150 in which combustion is performed in the combustion chamber 15 is switched to the opposite side about once every several tens of minutes to reduce uneven distribution of heat in the coke oven 1 .

In addition, when B gas cannot be used because the blast furnace is out of operation, etc., rich gas combustion is performed using C gas instead of M gas as the fuel gas. In this case, the C gas supplied from the C gas line 60 is introduced into the C gas horizontal flue 14, is supplied to each flue 150 of the combustion chamber 15 from the gas supply port called the C gas port 141, and is supplied to each flue 150 merges with air and burns. Air and exhaust gas follow the same paths as in lean gas combustion.

Here, in recent years, in the steel industry, as the age of the coke oven increases, the deterioration of the furnace body progresses, and among the flues in the combustion chamber, the end flues at both ends in the furnace width direction are not sufficiently supplied with fuel gas. The temperature drop of the end flue due to this has become a problem.

When the temperature of the end flue drops, the bricks used in the furnace body cool down from an overheated state and shrink, causing cracks and partial collapse, which may damage the furnace body of the coke oven. When the bricks at the end of the heat storage chamber are damaged, the M gas passage in the heat storage chamber through which the M gas supplied to the end flue passes is blocked, the flow rate of the M gas supplied to the end flue is insufficient, and the end flue is damaged. A temperature drop occurs. As a result, the carbonization of the coal at the fireside of the coke oven becomes insufficient, and the yield of coke production deteriorates due to poor coking. Furthermore, due to poor coking of coal at the fireside of the coke oven, clogging occurs sporadically in which the coke cannot be pushed out by the extruder, which also tends to cause damage to the coke oven body. In addition, due to poor coking of coal at the fireside of the coke oven, when the coke is extruded by the extruder, uncoked coal generates a large amount of dust, resulting in environmental deterioration. As described above, the temperature drop of the end flue causes various problems such as damage to the coke oven body, reduction in coke production efficiency, deterioration of the environment, and the like.

As a factor for the temperature drop of the end flue, it is considered that outside air enters the heat storage chamber through the joints of the bricks due to the deterioration of the furnace body, mixes with M gas in the heat storage chamber, and causes abnormal combustion. Specifically, the bricks of the heat storage chamber on the outside air side, that is, on the end flue side are damaged, blocking the path of M gas, and the supply of M gas from the heat storage chamber to the end flue becomes insufficient. It is conceivable that the amount of gas combustion at

In order to improve such problems, for example, as disclosed in Patent Document 1, a method of increasing the temperature of the end flue by installing a burner in the end flue and supplying gas and air has been proposed. It has been put to practical use.

JP-A-8-176550

However, in the conventional technique disclosed in Patent Document 1, there is a problem that a large amount of money is required to install a burner on the end flue and add a fuel switching device accordingly. In addition, the provision of a hole for embedding a burner in the furnace body of the coke oven has also caused a problem that deterioration of the furnace body is likely to progress.

In order to increase the temperature of the flue at the end of the combustion chamber, there is also a method of opening the heat storage chamber and replacing the damaged bricks at the end. Since the furnace body cools down, the deterioration of the furnace body is likely to progress, and the cost is high, so it was difficult to implement.

Therefore, the present inventors have made intensive studies on a method for increasing the temperature of the end flue without modifying the coke oven body, and have arrived at the present invention. An object of the present invention is to provide a coke oven, a method for supplying fuel gas to the coke oven, and a method for producing coke that can raise the temperature of the end flue with a simple configuration in order to solve the above problems. .

In order to solve the above problems, the present invention has the following features.

[1] A combustion chamber configured with a plurality of flues in the width direction of the furnace for burning by being supplied with lean gas or rich gas and combustion air, and combustion in the combustion chamber with the lean gas, the combustion air, and the combustion chamber. and a heat storage chamber through which exhaust gas passes through and preheats the lean gas and the combustion air with the heat of the exhaust gas; and a rich gas horizontal flue leading to each of the flues, wherein the lean gas is fed from a lean gas line that supplies the lean gas to the regenerator without passing through the regenerator. A coke oven further comprising a bypass line leading into a horizontal flue, and a nozzle supplying said lean gas introduced from said bypass line to any of said flues.

[2] The coke oven according to [1], wherein the nozzle is provided below an end flue among the plurality of flues.

[3] The coke oven according to [1] or [2], wherein the nozzle is provided so as to open upward.

[4] The bypass line according to any one of [1] to [3], wherein the bypass line is arranged so as to pass through an inspection port provided at the end of the rich gas horizontal flue in the furnace width direction. coke oven.

[5] The coke oven according to any one of [1] to [4], wherein the lean gas is M gas.

[6] A combustion chamber configured with a plurality of flues in the width direction of the furnace for combustion by being supplied with lean gas or rich gas and combustion air, and combustion in the combustion chamber with the lean gas, the combustion air, and the combustion chamber. and a heat storage chamber through which exhaust gas passes through and preheats the lean gas and the combustion air with the heat of the exhaust gas; a rich gas horizontal flue leading to each of the flues, said fuel gas supplying method for supplying said lean gas and said rich gas to a coke oven comprising: one of said lean gas supplied to said combustion chamber; is introduced into the rich gas horizontal flue from the lean gas line that supplies the lean gas to the heat storage chamber without passing through the heat storage chamber and is supplied to any of the flues, fuel to the coke oven Gas supply method.

[7] The method of supplying fuel gas to a coke oven according to [6], wherein the lean gas introduced into the rich gas horizontal flue from the lean gas line is discharged below the end flue of the combustion chamber.

[8] The method of supplying fuel gas to a coke oven according to [6] or [7], wherein the lean gas introduced from the lean gas line into the rich gas horizontal flue is discharged upward.

[9] introducing the lean gas from the lean gas line into the rich gas horizontal flue so as to pass through an inspection port provided at the end of the rich gas horizontal flue in the furnace width direction; [8] A method for supplying fuel gas to a coke oven according to any one of [8].

[10] The method of supplying fuel gas to a coke oven according to any one of [6] to [9], wherein the lean gas is M gas.

[11] A method for producing coke, comprising producing coke using the method for supplying fuel gas to a coke oven according to any one of [6] to [10].

According to the coke oven, the method for supplying fuel gas to the coke oven, and the method for producing coke according to the present invention, part of the lean gas is directly fed from the lean gas line into the rich gas horizontal flue without passing through the heat storage chamber. can be introduced. Therefore, even if the coke oven deteriorates and the poor gas supply to the end flue becomes insufficient, the end flue can increase the gas combustion amount of the end flue with a simple configuration without modifying the coke oven body. Flue temperature can be effectively increased.

FIG. 1 is a diagram showing the flow of fuel gas in a Karl steel coke oven. FIG. 2 is an enlarged view showing the main part of the coke oven of the present invention. FIG. 3 is a graph showing the effect of the coke oven and the method of supplying fuel gas to the coke oven of the present invention. FIG. 4 is a graph showing the effects of the coke oven and the method of supplying fuel gas to the coke oven of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, with reference to drawings, embodiment of the coke oven of this invention, the method of supplying fuel gas to a coke oven, and the method of manufacturing coke is described in detail.

FIG. 1 shows a cross section of the coke oven 1 of this embodiment in the oven width direction. Arrows in FIG. 1 indicate the flow of combustion gas within the coke oven 1 . The coke oven 1 of the present embodiment uses both coke oven gas (C gas), which is rich gas, and blast furnace gas (B gas), which is poor gas, or a mixed gas (M gas) of B gas and C gas. This is the double furnace used.

The combustion chambers 15 are alternately arranged adjacent to the carbonization chambers (not shown) in the lengthwise direction of the furnace to form a furnace cluster. As shown in FIG. 1, the combustion chamber 15 of the coke oven 1 is provided with a large number of flues 150 in the width direction of the furnace, and each flue 150 contains M gas (poor gas) or C gas (rich gas) and air (combustion air) are supplied for combustion.

A heat storage chamber 13 is provided below the combustion chamber 15 . The heat storage chamber 13 is provided with a passage through which the M gas, air, and the exhaust gas after combustion in the combustion chamber pass, and the M gas and the air are preheated by the heat of the exhaust gas. Below the heat storage chamber 13, a lower horizontal flue 12 is provided for separately introducing the M gas and air preheated in the heat storage chamber 13. As shown in FIG.

The coke oven 1 of the present embodiment is a two-part Carl-Steel-type coke oven, and each of the heat storage chamber 13 and the combustion chamber 15 is located approximately in the center in the oven width direction on the extruder side and the fire extinguisher side. It is split in two. In the coke oven 1, the direction of introduction of the fuel gas is switched to the opposite direction at regular time intervals, for example, once every several tens of minutes, and combustion is alternately repeated on the extruder side and the fire extinguisher side. Above the combustion chamber 15, an upper horizontal flue 16 is provided through which exhaust gas after combustion in each flue 150 passes.

An M gas line (poor gas line) 50 through which the M gas supplied to the coke oven 1 passes, and a C A gas line (rich gas line) 60 is provided.

Below the combustion chamber 15 and between the heat storage chamber 13, there is a C gas horizontal flue (rich gas horizontal flue) 14 that guides the C gas supplied from the C gas line 60 to each flue 150. , are provided so as to extend in the furnace width direction. C gas contains a large amount of hydrocarbon gas, and if it is passed through the heat storage chamber 13, it may decompose and generate soot. 14 directly into each flue 150 of combustion chamber 15 for combustion.

During lean gas combustion, the M gas and air supplied from the M gas line 50 are separately introduced from the heat valve 11 into the lower horizontal flue 12, preheated in the heat storage chamber 13, and then introduced into the combustion chamber 15. be done. Specifically, the M gas and air preheated in the heat storage chamber 13 are supplied into the flue 150 from a plurality of heights on the side surface of each flue 150, mixed with each other, and combusted.

In addition, when B gas cannot be used because the blast furnace is out of operation, etc., rich gas combustion is performed using C gas instead of M gas as the fuel gas. In this case, the C gas supplied from the C gas line 60 is supplied to each flue 150 of the combustion chamber 15 from the C gas port 141 provided at the lower end of each flue 150 through the C gas horizontal flue 14 . Then, it joins with air supplied from a plurality of heights on the side surface inside each flue 150 and burns.

FIG. 2 shows a partially enlarged view of the coke oven 1 of this embodiment. As shown in FIG. 2, in the coke oven 1 of the present embodiment, the cover (cross piece) of the heat valve 11 that introduces the M gas from the M gas line 50 to the lower horizontal flue 12 is attached to the distributor 17 with branches. A modified bypass line 18 is provided to directly introduce the M gas from this distributor 17 into the C gas horizontal flue 14 . The bypass line 18 is composed of a flexible hose or pipe, and a nozzle 19 is provided at the tip of the bypass line 18 . M gas is supplied from this nozzle 19 to one of the plurality of flues 150 in the combustion chamber 15 .

In the present embodiment, as shown in FIG. 2, the nozzle 19 has an L-shaped shape, and is opened upwardly so that the nozzles 19 are arranged below the end flues 150a at both ends in the furnace width direction among the plurality of flues 150. is provided in That is, the nozzle 19 is provided directly below the C gas port 141 provided at the lower end of the end flue 150a so as to open toward the C gas port 141. As shown in FIG. If the tip of the bypass line 18 is simply arranged near the end flue 150 a without using the nozzle 19 , the M gas introduced from the bypass line 18 is widely diffused into the C gas horizontal flue 14 and reaches all the flues 150 . As a result, the temperature of the end flue 150a cannot be effectively raised. On the other hand, as described above, by providing the nozzle 19 below the end flue 150a or providing it so as to open upward, the end flue 150a and the flue 150 in the vicinity thereof can be selectively M gas from the nozzle 19 can be additionally supplied. As a result, it is possible to easily and effectively raise the temperature of the end flue 150a where the supply amount of M gas is insufficient and the flue 150 in the vicinity thereof.

In addition, as in this embodiment, by additionally supplying M gas from the nozzle 19 installed in the C gas horizontal flue 14, compared to the case where only the end flue 150a is heated by a burner etc., only the end flue 150a In addition, the effect of simultaneously raising the temperature of several flues adjacent to this is also obtained.

In addition, the bypass line 18 is inserted into a multipurpose window (inspection port) 140 used for cleaning and inspection of the C gas horizontal flue, which is provided at the end of the C gas horizontal flue 14 in the furnace width direction. 140 is arranged. By doing so, even in the existing coke oven, if the distributor 17, the bypass line 18 and the nozzle 19 are added, the coke oven and the method for supplying fuel gas to the coke oven and the method for producing coke according to the present invention can be applied.

Further, the method of supplying fuel gas to the coke oven of the present embodiment supplies M gas and C gas to the coke oven 1 having the above configuration. Specifically, the M gas introduced into the C gas horizontal flue 14 from the M gas line 50 is discharged below the end flue 151 of the combustion chamber 15 . The M gas introduced into the C gas horizontal flue 14 from the M gas line 50 is discharged upward. Then, the M gas is introduced from the M gas line 50 into the C gas horizontal flue 14 so as to pass through the multi-purpose window 140 provided at the end of the C gas horizontal flue 14 in the furnace width direction.

Further, the method for producing coke according to the present embodiment is carried out by producing coke using the above-described method for supplying fuel gas to a coke oven.

In the above-described embodiment, an example in which the present invention is applied to a Karl steel coke oven has been described, but the coke oven, the method for supplying fuel gas to the coke oven, and the method for producing coke according to the present invention may be applied to other types. It can also be applied to a chamber furnace type coke oven.

Tests were conducted using an actual coke oven to confirm the effects obtained by the coke oven, the method for supplying fuel gas to the coke oven, and the method for producing coke according to the present invention. A coke oven in which the temperature of the end flue 150a is constantly low was selected as a test object. A distributor 17, a bypass line 18 and a nozzle 19 were added to the coke oven according to the above-described embodiment. The nozzle was installed facing upward only directly below the C gas port 141 of the end flue 150a closest to the extruder. Then, before and after adding the distributor 17, the bypass line 18, and the nozzle 19, the introduction direction of the fuel gas is switched to the opposite direction every 20 minutes, and combustion is alternately repeated on the extruder side and the fire engine side. A lean gas combustion of coke oven 1 was performed. After adding the distributor 17, the bypass line 18 and the nozzle 19, M gas was additionally supplied from the nozzle 19 to the end flue 150a. The temperature of 35 flue 150 in the oven width direction of the coke oven 1 was measured before adding the distributor 17, the bypass line 18 and the nozzle 19, one day after adding, and two days after adding.

FIG. 3 shows the temperature distribution of each flue 150 before the addition of the distributor 17, the bypass line 18 and the nozzle 19, one day after the addition, and two days after the addition. Flue numbers in FIG. 3 indicate the order of the flues 150 counted from the extruder side.

As shown in FIG. 3, after the application of the present invention, that is, on the first day and the second day after the addition of the distributor 17, the bypass line 18 and the nozzle 19, the temperature of the entire combustion chamber 15 was maintained while the nozzle 19 The temperature of the end flue 150a immediately above and several flues 150 adjacent to the end flue 150a could be effectively raised.

Further, in the same coke oven, five combustion chambers 15 in which the temperature of the end flue 150a is constantly low were selected, and distributors 17, bypass lines 18 and nozzles 19 were added for each of these five combustion chambers 15. Then, the temperature of the end flue 150a of the coke oven 1 was measured before and after the distributor 17, the bypass line 18 and the nozzle 19 were additionally installed. FIG. 4 shows the five-day average temperature of the end flue 150a in each of the five combustion chambers before and after adding the distributor 17, bypass line 18, and nozzle 19 in comparison. As shown in FIG. 4, in all five combustion chambers, the temperature of the end flue 150a could be effectively increased after the bypass line 18 was installed.

1 coke oven 11 heat valve 12 lower horizontal flue 13 heat storage chamber 14 C gas horizontal flue (rich gas horizontal flue)
140 multi-purpose window (inspection door)
141 C gas port 15 combustion chamber 150 flue 150a end flue 16 upper horizontal flue 17 distributor 18 bypass line 19 nozzle 50 M gas line (lean gas line)
60 C gas line (tomi gas line)

Claims (11)

a combustion chamber configured with a plurality of flues in the width direction of the furnace for burning by being supplied with poor gas or rich gas and combustion air;
a heat storage chamber through which the lean gas, the combustion air, and the exhaust gas after combustion in the combustion chamber pass, and preheating the lean gas and the combustion air with the heat of the exhaust gas;
A coke oven comprising a rich gas horizontal flue provided to extend in the furnace width direction below the combustion chamber and guiding the rich gas to each of the flues,
a bypass line that introduces the lean gas from a lean gas line that supplies the lean gas to the heat storage chamber into the rich gas horizontal flue without passing through the heat storage chamber;
a nozzle for supplying the lean gas introduced from the bypass line to any of the flues. 2. The coke oven according to claim 1, wherein said nozzle is provided below an end flue of said plurality of flues. 3. The coke oven according to claim 1, wherein said nozzle is provided so as to open upward. The coke oven according to any one of claims 1 to 3, wherein the bypass line is arranged so as to pass through an inspection port provided at the end of the rich gas horizontal flue in the oven width direction. The coke oven according to any one of claims 1 to 4, wherein the poor gas is M gas. a combustion chamber configured with a plurality of flues in the width direction of the furnace for burning by being supplied with poor gas or rich gas and combustion air;
a heat storage chamber through which the lean gas, the combustion air, and the exhaust gas after combustion in the combustion chamber pass, and preheating the lean gas and the combustion air with the heat of the exhaust gas;
supplying the lean gas and the rich gas to a coke oven comprising a rich gas horizontal flue that is provided below the combustion chamber and extends in the oven width direction and guides the rich gas to each of the flues. A fuel gas supply method comprising:
A portion of the lean gas supplied to the combustion chamber is introduced into the rich gas horizontal flue from a lean gas line that supplies the lean gas to the heat storage chamber without passing through the heat storage chamber. A method of supplying fuel gas to a coke oven, supplying to any of 7. A method of supplying fuel gas to a coke oven according to claim 6, wherein said lean gas introduced into said rich gas horizontal flue from said lean gas line is discharged below said end flue of said combustion chamber. 8. The method of supplying fuel gas to a coke oven according to claim 6 or 7, wherein said lean gas introduced into said rich gas horizontal flue from said lean gas line is discharged upward. 9. The lean gas is introduced into the rich gas horizontal flue from the lean gas line so as to pass through an inspection port provided at the end of the rich gas horizontal flue in the furnace width direction. 2. A method of supplying fuel gas to a coke oven according to claim 1. The method of supplying fuel gas to a coke oven according to any one of claims 6 to 9, wherein said poor gas is M gas. A method for producing coke, comprising producing coke using the method for supplying fuel gas to a coke oven according to any one of claims 6 to 10.

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