JPH0663334A - Method for preventing discharge of black smoke from coke furnace - Google Patents

Abstract

PURPOSE:To prevent the discharge of black smoke from the chimney of a coke furnace by installing a box which is branched to a dust collecting system and a flue system and is commonly used regardless of odd or even pull on the downstream of the waste gas valve of the coke furnace, providing a dust concn. measuring instrument and operating selector valves by this meter and a timer. CONSTITUTION:The common box 9 for odd/even pull of a combustion chamber branched to the two systems; the flue side 8 and the dust collector side 14 is installed on the downstream of the waste gas valve 5 of the waste gas system of the coke furnace via a pressure regulator 6 on the downstream side of the waste gas valve. The selector valves 7, 12 to the flue system 8 and the dust collection system 14 are reverse operated by the detection by the duct concn. measuring instrument 10 provided in this common box 9 and the operation timer. The operation timer is combined with a coal charge start signal in such a manner. The waste gas is changed over to the dust collector 14 side in the initial period coal charge when the black smoke is liable to be generated. The waste gas is changed over to the flue 8 side when the discharge of the black smoke decreases.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention charges coal into a carbonization chamber of a coke oven and carbonizes the high temperature of the combustion chambers on both sides of the carbonization chamber using the respective partition brick walls as heat transfer bodies. It is related to black smoke emission prevention of the coke oven that prevents black smoke from being emitted from the chimney.

[0002]

2. Description of the Related Art In a coke oven, a carbonization chamber for the dry distillation of coal and a combustion chamber for heating the coal are arranged on both sides of the carbonization chamber through partition walls made of bricks, and the combustion chamber on one side is arranged. Is composed of a large number of kilns in an arrangement of combustion chamber-carbonization chamber-combustion chamber-carbonization chamber-combustion chamber so as to be shared with the adjacent carbonization chamber. In such a state, the coal charged in the carbonization chamber is burned with the fuel gas in the combustion chamber, so that the brick partition wall is reduced to about 1
The temperature is raised to 200 to 1300 ° C., and the coal is carbonized into coke for about 15 to 19 hours. Volatile components in the coal charged by the carbonization are separated from the coal and volatilized to form a gas body, which is guided to the outside of the furnace by an intake blower. Although the intake blower draws a certain negative pressure as described above, the volatile matter during carbonization tends to decrease the most immediately after carbonization. Immediately after that, about 20 mmAq has a characteristic of decreasing to about 0 mmAq as a quadratic curve after about 7 to 12 hours.

On the other hand, the waste gas from the combustion chamber generally gives heat to the brick when passing through the heat storage chamber below the combustion chamber and becomes low temperature and is exhausted, but the dry distillation time of the coke is long as described above. Since it is time, in order to maintain the heat storage capacity of the heat storage chamber, which contributes to the improvement of the combustibility in the combustion chamber and the improvement of thermal efficiency, as shown in FIG. 6, it passes through the odd side exhaust gas valve / even side waste gas valve at regular intervals. It has been switched so that it can be discharged from the chimney through the flue. That is, in the normal coke oven, as shown in FIG. 5, the waste gas burned in the combustion chamber of the coke oven 1 passes through the heat storage chamber 4 below the combustion chamber, and the waste gas valve 5 and the waste air valve lower pressure adjusting valve 6 And is discharged to the atmosphere from the chimney after flowing through the flue 8 arranged in parallel with the furnace group.

FIG. 6 is an explanatory view of a normal type odd / even pulling operation switching, in which a front view of a part of the coke oven and a vertical sectional side view of the combustion chamber / heat storage chamber (left) are combined (FIG. 6 shows the combustion chamber). Although only the case of 2 is illustrated, the same applies to the combustion chamber 2a and other combustion chambers), and FIG. 6 (A) shows odd pulling,
The fuel burned in the combustion chamber 2 receives the heat of the heat storage chamber 4B at the fuel injection port 19a and the air receives the heat of the heat storage chamber 4B at the combustion air injection port 20a to become a high temperature and rapidly burns in the combustion chamber to cause the partition wall as described above. While flowing into the flue 8 through the waste gas valve 5 to heat the heat storage chamber 4A to lower the temperature. And
When a sufficient amount of heat reaches the heat storage chamber 4A after a certain period of time, FIG.
Switching is performed by opening the exhaust gas valve 5a and closing the exhaust gas valve 5 shown in the "even pulling" state of (B). FIG. 6 (B) shows even pulling, which is the reverse of FIG. 6 (A). The fuel that burns in the combustion chamber is the fuel input port 19 and the air is the combustion air input port 20. The heat of the heat storage chamber 4A received in the stroke is received and burned to a high temperature, flows in the direction of the arrow and gives heat to the heat storage chamber 4B, flows through the waste gas valve 5a to the flue 8, and repeats this. The coke having an appropriate quality by such a heating (dry distillation) operation is mechanically extruded outside the furnace by an extruder.

Therefore, when the operation is continued for a long period of time, the brick walls, which are the respective partitions, undergo thermal transformation due to temperature change.
Mechanical friction during extrusion and deformation due to external force due to extrusion irregularity (clogging) causes a "gap" in the joints between bricks on the brick wall, and the gas produced by carbonization of coal is the waste gas system described above. It flows out into and becomes black smoke from the chimney. That is, each of the combustion chambers adjacent to the carbonization chamber and the brick wall interacts with each other through the joint gap of the brick wall, and when the coke oven tends to age, a gap is likely to be formed in the brick joint. The combustion gas emitted to the atmosphere becomes black smoke.

Since this black smoke causes a problem of "pollution / work environment", it is necessary to take measures against it. Conventionally, as a "black smoke emission prevention measure" for this, a "smoke exhaust system" leading to a chimney
Since there are many opportunities to generate black smoke in the early stage after carbonization due to the installation of an electrostatic precipitator or a bag filter, and the balance between the amount of gas produced by carbonization and the amount of suction blower suctioned as described above, this opportunity is mainly used. There have been methods such as separating into a dust collector system that is installed in a separate system to collect dust, but the equipment will be large in size or equipped to handle with a waste air valve for one unit. Due to the large number, it is difficult to process in a small space.

Therefore, the present invention has conducted a study to eliminate the above-mentioned drawbacks and reliably prevent the emission of black smoke. As a result, a soot dust concentration meter is installed in the vicinity of the coke oven outlet and the smoke emission system is directly controlled by the amount. The present invention has been completed by finding that it is certain that switching to a conventional flue and a dust collecting device can be performed in two series. That is, according to the present invention, a soot concentration meter is provided between the combustion chamber outlet of the coke oven and the flue, and the waste gas valve outlet is branched into the two series, and the switching valve is arranged at each of the two sequences, and the soot concentration meter is instructed. Another object of the present invention is to provide a method for preventing discharge of black smoke in a coke oven, which is characterized in that these valves are switched in reverse operation so as to flow to a flue system or a dust collection system.

[0008]

In order to achieve the above object, a method for preventing black smoke in a coke oven according to the present invention has a large number of carbonization chambers which are heated from adjacent combustion chambers through partition walls.
In a coke oven that discharges waste gas from the combustion chamber from a chimney through a waste gas valve, a common box that is shared downstream of the waste gas valve through an exhaust gas valve downstream side pressure adjusting valve without distinction between odd / even Is installed, and a soot and dust concentration meter that detects soot and dust in the exhaust gas discharged through the exhaust air valve is installed in this, and the downstream side of the common box is branched into two systems, a flue system and a dust collection system. A switching valve is installed, and the detection by a dust concentration meter and the operation timer are used to switch the exhaust air to a dust collection system when there is a large amount of dust, and to discharge it from the flue system to the atmosphere when there is a small amount of dust. When the charcoal start signal is combined with an operation timer, the exhaust air is switched to the dust collector side when black smoke is likely to occur in the initial stage of charcoal charging, and the exhaust air is switched to the flue side when black smoke emission becomes small. Is.

[0009]

In the coke oven, since the carbonization time for high temperature carbonization of coal is long, the combustibility in the combustion chamber is improved, the thermal efficiency is improved, and the heat storage capacity of the heat storage chamber is maintained. Therefore, as shown in FIG. 3 and FIG. This is called "odd / even drawing" and switches the flow path of the exhaust gas at regular intervals to prevent variations in the amount of heat stored. This will be described with reference to FIG. 3. FIG. 3A shows an odd-numbered pulling when the dust concentration is low, but the fuel that burns in the combustion chamber is the fuel inlet, and the air is the combustion air inlet. It receives the heat of the heat storage chamber 4B and becomes a high temperature, which rapidly burns in the combustion chamber to heat the partition wall, flows in the direction of the arrow and gives heat to the heat storage chamber 4A, becomes a low temperature, and passes through the waste gas valve 5 to the flue. Flowing. When a sufficient amount of heat is applied to the heat storage chamber 4A after a certain period of time, the exhaust gas valve 5 shown in the "even pulling" state at the time of low soot concentration in FIG. It is switched by opening 5a.

FIG. 4 (A) shows even pulling when the concentration of soot is low, but this shows the reverse state of FIG. 3 (A), and the combustion gas flows in the direction of the arrow to store heat. Heat is applied to the chamber 4B, flows through the exhaust valve to the flue, and is repeated. If there is a problem such as a gap in the brick partition wall here, the produced gas during carbonization will flow into the exhaust system and become black smoke. Therefore, as shown in FIGS. 3 and 4, Install a common box that is common for odd / even pull exhaust air,
The flue system and the dust collection system located downstream of it are branched into two series, and a soot concentration meter is installed in this common box, and the detection valves (instructions) reverse the valves of the flue system and the dust collection system. By doing so, the system is switched to the dust collection system when the soot concentration is high and to the flue system when the soot concentration is low.

In this way, the black smoke emission signal, which differs depending on various damage states of each kiln of the coke oven, is equipped with a common box for odd / even drawing which makes the exhaust gas valve outlet and later common, and the number of facilities is reduced. When the amount of soot is small due to the detection signal of the soot and dust concentration meter equipped with it, the flue system switching valve is opened, that is, the dust collection system switching valve is closed and the amount of soot is large. When the flue system switching valve is closed, that is, the dust collection system switching valve is opened, the dust concentration in the exhaust gas of the coke oven can be known directly with a dust concentration meter, and when the dust concentration is high. Only black smoke dust can be collected, so when the coke ovens are managed individually and the total soot dust content of the entire furnace group is low, the dust collection blower inlet damper can be closed with the aggregate value of the signal values to save energy. As a result, operating costs can be further reduced.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic plan view showing an example of the apparatus of the present invention, FIG. 2 is a schematic cross-sectional view (the same parts as those in the prior art are designated by the same reference numerals), 1 is a coke oven, 2, 2a, 2
b, 2c, 2d are combustion chambers, 3, 3a, 3b, 3c are carbonization chambers, 4 are heat storage chambers, 5, 5a, 5b, 5c are waste gas valves, 6 is a waste air valve downstream pressure control valve, 7 is Flue system switching valve, 8 is a flue, 9 is a common box for odd / even pulling, 10 is a dust concentration meter, 12 and 12a are dust collecting system switching valves, 13 is a dust collecting system inlet duct, 14 is a dust collector, 15 is a dust collecting blower inlet damper, 16 is a dust collecting blower, 17 is a dust collecting system outlet duct, 1
8 is a chimney, 19 and 19a are fuel inlets, and 20 and 20a are combustion air inlets.

As described above, the equipment structure of the coke oven 1 is such that the carbonization chambers 3, 3a, 3b, 3c are divided by brick partition walls, and the combustion chambers 2, 2a, 2b, 2c, 2d are provided on both sides. Arranged in such a way that it consists of 30 to 100 gates per furnace group. Further, the dust collecting system side of the odd / even pull common box 9 provided at the lower part of both waste gas valves of the one furnace and one system is connected to the dust collecting system duct 13 via the dust collecting system switching valve 12. And, as shown in FIG. 1, normally, the exhaust gas burned in the combustion chamber is
The exhaust gas valves 5, 5a, 5b, 5c and the exhaust gas valve downstream side pressure adjusting valve 6 (see FIG. 2) are adjusted to flow to the flue 8 installed parallel to the furnace group, and further from the chimney 18. Since it is discharged to the atmosphere and the dry distillation time of coke is long as described above, in order to maintain the heat storage capacity of the heat storage chamber that contributes to the improvement of the combustibility in the combustion chamber and the improvement of thermal efficiency, as shown in FIGS. This is called "odd / even drawing" to switch the flow path of the exhaust gas at regular intervals to prevent variations in the amount of heat stored.

FIG. 3 (A) is an explanatory diagram of the operation switching of the present invention for low-dust concentration odd-numbering, and FIG. 3 (B) is an illustration for switching high-dust concentration odd-numbering, and FIG. 4 (A). The figure is an explanatory diagram of the operation switching of the low soot concentration even pulling of the present invention, and the same (B) is an explanatory diagram of operation switching of the high dust concentration even pulling (FIGS. 3 and 4 show only the case of the combustion chamber 2, The same applies to the combustion chamber 2a and other combustion chambers), and this will be described with reference to FIGS. 3 and 4 for "odd / even drawing".
Although the drawing shows odd drawing, the fuel burned in the combustion chamber is at the fuel inlet 19a and the air is the combustion air inlet 20.
At a, the heat of the heat storage chamber 4B is received and becomes a high temperature, and rapidly burns in the combustion chamber 2 to heat the partition wall as described above, and in the direction of the arrow, heat is applied to the heat storage chamber 4A to become a low temperature. Through the exhaust valve 5 to the flue 8.

When sufficient heat is applied to the heat storage chamber 4A after a certain period of time, the exhaust gas valve 5 is closed and the exhaust air valve 5a is opened as shown in the even-numbered state of FIG. 4 (A). Change 4 (A) shows even pulling, which is the reverse of FIG. 3 (A), in which the fuel that burns in the combustion chamber is the fuel inlet 19 and the air is the combustion air inlet 20. Then, the heat of the heat storage chamber 4A, which has received heat in the previous process, is received and burns to a high temperature.
It flows in the direction of the arrow to give heat to the heat storage chamber 4B, and then to the flue 8 through the exhaust gas valve 5a, and this is repeated.

If a problem occurs such as a gap being formed in a brick partition wall, the gas produced during carbonization will flow into the exhaust system and produce black smoke. An odd / even pull common box 9 that is commonly used for odd / even waste air is installed via the downstream pressure control valve 6, and the common box 9 is used to measure the dust concentration in the waste gas. A soot and dust concentration meter 10 (see FIG. 2) is provided, and the downstream side of the common box 9 is branched into two systems, a flue system and a dust collection system, and the flue system switching valve 7 and the dust collection system that respectively operate in reverse. The switching valve 12 is provided to install a simple mechanism for one furnace and one system for each kiln.

As shown in FIG. 3 and FIG. 4, when the dust concentration is low, there is no distinction between “odd / even pull” operation in the common box after the exhaust gas valve downstream side pressure control valve outlet, and when the dust concentration is low (in FIG. A) Figure,
Alternatively, as shown in FIG. 4 (A), the flue system switching valve 7 may be opened and flowed to the flue 8. If the dust concentration is high, FIG. 3 (B) or FIG. B) Flue system switching valve 7 as shown
Close and allow the dust collection system to exhaust. That is, the flue system switching valve 7 is provided with an operation function of "disconnecting or communicating" the flow to the flue 8, and "disconnecting / disconnecting" the normal exhaust system.
By adding the function of "through", the dust collection system switching valve 12 is provided with an operation function of "off or through" to the dust collection system for the purpose of collecting black smoke.

In this way, the "black smoke emission signal" differs depending on various damage states of each kiln of the coke oven,
Equipped with a common box 9 for odd / even pulling that shares the exhaust gas valve downstream side pressure control valve outlet and later, so that when there is little dust due to the detection signal of the dust concentration meter 10 installed in it regardless of odd / even pulling Indicates that the flue system switching valve 7 is open, that is, the dust collection system switching valve 12 is closed. When the amount of soot and dust is large, the flue system switching valve 7 is closed, that is, the dust collection system switching valve 12 is opened, and the soot and dust concentration in the coke oven exhaust gas is directly known by the soot and dust concentration meter 10 and installed. Not only the timer control at the time of charcoal, but black smoke dust can be collected only when the dust concentration is high due to damage to the furnace wall.

Further, the waste air valve downstream side pressure adjusting valve 6 in the figure is
In addition to the characteristics of many coke ovens and the conventional exhaust system to the chimney, a valve capable of absorbing and adjusting the difference in the piping resistance value of the black smoke dust collection system according to the present invention is provided, so that the coke oven combustion is subtle. by the Do adjusted, is effective in reducing and low NO _X reduction of fuel consumption rate is also the help of an ideal combustion control.

[0020]

The present invention has the above-described structure, and is provided on the downstream side of the exhaust gas valve of the exhaust gas system that exits from the combustion chamber of the coke oven through the heat storage chamber.
Through the exhaust air valve downstream side pressure control valve, a common box that is divided into two systems, a dust collection system and a flue system, is installed, and a dust concentration meter is installed. By operating the series dust collection system switching valve and the flue system switching valve, it is possible to reliably detect the amount of soot dust depending on the condition of each coke oven.
You can switch to the flue side and reliably prevent black smoke from being emitted from the chimney. In addition, the combination of the coal-charging start signal and the operation timer can reliably handle the main target period in which black smoke is likely to occur in the initial stage of coal-charging. In addition, the above-mentioned odd / even pulling common box is installed to provide a soot concentration meter, and by detecting the soot concentration in the coke oven waste gas, black smoke dust can be collected only when the soot concentration is high. When the total dust content of the entire furnace group is low, the dust collection blower inlet damper is closed by the aggregate value of the signal values to save energy and further reduce operating costs. Further, according to the method of the present invention, it is necessary to switch all the exhaust gas valves to the dust collecting system, and to switch the exhaust gas valves one by one and adjust the pressure without passing through the exhaust gas valves due to pulling. Equipped with an odd / even pull common box as compared with the conventional method and apparatus, the number of equipment can be reduced by half, control can be facilitated, and operation complexity and apparatus waste can be reduced. There is.

[Brief description of drawings]

FIG. 1 is a schematic plan view showing an embodiment of the device of the present invention.

FIG. 2 is a schematic vertical sectional view of FIG.

FIG. 3A is an explanatory diagram of an odd-numbered operation switching of a low soot concentration in the present invention, and FIG. 3B is an explanatory diagram of an odd-numbered operation switching of a high soot concentration in the present invention.

FIG. 4A is an explanatory diagram of odd-numbered operation switching of low soot concentration in the present invention, and FIG. 4B is an explanatory diagram of even-numbered operation switching of high soot concentration in the present invention.

FIG. 5 is a schematic cross-sectional view of a normal type coke oven.

FIG. 6 is an explanatory diagram of odd / even pull operation switching of the same normal type.

[Explanation of symbols]

 1 Coke oven 2,2a, 2b, 2c, 2d Combustion chamber 3,3a, 3b, 3c Carbonization chamber 4,4A, 4B Heat storage chamber 5,5a, 5b, 5c Waste gas valve 6 Waste gas valve Downstream pressure control valve 7 Flue system switching valve 8 Flue 9 Common box for odd / even pulling 10 Dust concentration meter 12 Dust collecting system switching valve 13 Dust collecting system inlet duct 14 Dust collector 15 Dust collecting blower inlet damper 16 Dust collecting blower 17 Dust collecting System outlet duct 18 Chimney 19, 19a Fuel inlet 20, 20a Combustion air inlet

Front page continuation (72) Inventor Shujiro Takada 519-14 Shimomitsubashicho, Yamatokoriyama City, Nara Prefecture

Claims (1)

[Claims] 1. A coke oven having a large number of carbonization chambers heated from adjacent combustion chambers via partition walls and discharging exhaust gas from the combustion chambers from a chimney via a exhaust gas valve. A common box is installed downstream of the exhaust gas valve via the pressure control valve on the downstream side without distinction between odd number and even number, and a soot and dust concentration meter for waste gas is installed in this box, and the downstream side of the common box is the flue system. And a dust collection system are divided into two systems, and a switching valve is arranged in each of the two systems, and by the detection by the dust concentration meter and the operation timer,
When the amount of soot is large, the waste air is switched to a dust collection system, and when the amount of soot is small, it is switched so that it is discharged to the atmosphere from the flue system. A black smoke emission prevention method for the coke oven that switches the exhaust air to the dust collector side when it is easy to come out and switches the exhaust air to the flue side when the black smoke emission becomes low.