JPH1135944A - Method for controlling temperature taper of furnace wall of coke oven - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for controlling the temperature taper of the furnace wall of a coke oven which makes the coking time and soaking time nearly the same in the direction of the furnace length while retaining the temperature distribution in the direction of the furnace length in the carbonizing chamber at an appropriate distribution. SOLUTION: By using the standard deviation σ of the temperature taper of a furnace wall, a waste gas discharge set flow area ratio in each carbonizing chamber is calculated by restricting the size of a deviation of the temperature taper of the furnace wall between the previously set target temperature taper of the furnace wall and the actual temperature taper of the furnace wall and from the flow area ratio per carbonizing chamber, the flow area ratio of the horizontal flues which can minimize the dispersion of the flow area ratio among horizontal flues is obtained to adjust the degree of opening of each damper depending on the flow area ratio.

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 a wall temperature of a coke oven in which a plurality of rows of carbonization chambers and combustion chambers are arranged.

[0002]

2. Description of the Related Art In general, a coke oven forms one oven by a pair of a carbonization chamber and a combustion chamber which are alternately arranged in a plurality of rows in the oven width direction. Usually, 50 to 100 ovens are gathered to form one oven. It constitutes a furnace group. Each combustion chamber is adjacent to a carbonization chamber via a furnace wall (brick wall), and is further divided into 20 to 30 small combustion chambers in the furnace length direction. The bottom of each small combustion chamber is connected to a heat storage chamber. I have.

[0003] Each of the small combustion chambers is supplied with fuel gas and air preheated through a preheating heat storage chamber, and the combustion thereof heats the carbonization chambers on both sides through the furnace wall, thereby carbonizing the coal. Exhaust gas generated in each of the small combustion chambers is drawn down to a heat recovery heat storage chamber and recovered. Exhaust gas discharged to the horizontal flue is directed to the front side of the furnace (hereinafter referred to as “furnace front side”) according to an exhaust gas discharge flow area ratio determined by the degree of opening of dampers (waist dampers) provided at both ends of the horizontal flue. ) And the flow is distributed to the rear side of the furnace (hereinafter, referred to as the "rear side of the furnace"), collected in a flue via respective dampers, and discharged from the chimney to the atmosphere. And the heat storage chamber for preheating and the heat storage chamber for heat recovery,
The switching is alternately performed in a control cycle of 30 minutes. Hereinafter, the heat storage chamber for preheating is referred to as “standing side”, and the heat storage chamber for heat recovery is referred to as “pulling side”.

The carbonization chamber has a width of 400 to 500 mm and a length of 2
It is a room surrounded by bricks of 0 to 30 m and height of 4 to 6 m, and coal is charged from a coal charging inlet on the upper surface of the room. The coke carbonized in the carbonization chamber is extruded from the rear side of the furnace by an extruder and taken out from the front side of the furnace. Usually, the furnace width of the coking chamber is slightly wider at the front side of the furnace than at the rear side of the furnace so that coke can be easily pushed out of the coking chamber. In the carbonization chamber, since heat is supplied from both side walls, carbonization proceeds from both sides, and the point at which carbonization is completed up to the center of the furnace width, that is, the point at which all carbonization is completed is called `` fire fall ''
The time from the charging of coal to this point is called "fire-out time".

[0005] Further, even after the completion of carbonization, coke remains at 2%.
The heat is kept as it is in the carbonization room for about 4 hours. This time is called “place time”. This setting time is used to achieve uniform heating and shrinkage of the coke and to make it easy to extrude. If it is too short, this object cannot be achieved. on the other hand,
If the placing time is too long, it may cause damage to the furnace body such as deformation of the furnace lid, so the placing time must be maintained at an appropriate length. Therefore, in the operation of the coke oven, it is desired that the burn-out time and the setting time of the coal at any position in the furnace length direction of the coking chamber be approximately the same time,
The temperature distribution in the furnace length direction of the coking chamber is adjusted in order to make the burn-down time and the storage time the same. Adjustment of the temperature distribution in the furnace length direction of the coking chamber is performed by the fuel distribution of each small combustion chamber in the furnace length direction, but its control requires a high degree of experience and skill and is extremely difficult.

As described above, since the carbonization chamber is slightly widened from the rear side of the furnace to the front side of the furnace, the amount of coal charged is distributed in the furnace length direction according to the furnace width. Further, the exhaust system of the exhaust gas generated in the combustion chamber is complicated as schematically shown in FIG. 4, and it is extremely difficult to control the temperature distribution in the furnace length direction of the coking chamber.

That is, in FIG. 4, in the first half cycle of combustion (when the heat storage chamber (i) is on the pulling side), the exhaust gas generated in the combustion chamber (i) and the combustion chamber (i + 1) passes through a path shown by a solid line. It is drawn down to the heat storage chamber (i) and discharged to the horizontal flue (i). The exhaust gas discharged to the horizontal flue (i) is distributed to the furnace front side and the furnace rear side according to the exhaust gas discharge flow area ratio determined by the opening degree of the damper provided on the front side and the rear side of the furnace. Through the flue.

In the second half cycle of combustion (when the heat storage chamber (i-1) and the heat storage chamber (i + 1) are on the pulling side), the combustion chamber (i-
The exhaust gas generated in 1) and the combustion chamber (i) is drawn down to the heat storage chamber (i-1) via a path shown by a broken line, and is discharged to the horizontal flue (i-1). Further, the exhaust gas generated in the combustion chamber (i + 1) and the combustion chamber (i + 2) is drawn down to the heat storage chamber (i + 1) via a path shown by a broken line, and is discharged to the horizontal flue (i + 2).
It is discharged to 1). Horizontal flue (i-1) and horizontal flue (i
Exhaust gas discharged to the horizontal flue (i)
-1) and the flow rate of exhaust gas is determined according to the opening ratio of the damper provided on the front side and the rear side of the furnace of the horizontal flue (i + 1), and the flow rate is distributed between the front side and the rear side of the furnace. Released into the stack.

Therefore, the exhaust gas generated in the combustion chamber (i) and the combustion chamber (i + 1) on both sides of the carbonization chamber (i)
It is referred to as "each carbonization chamber exhaust gas." ) In the first half cycle of combustion, the flow rate is distributed between the front side and the rear side of the furnace according to the ratio of exhaust gas discharge and circulation area of the horizontal flue (i).
The flow rate is distributed between the front side of the furnace and the rear side of the furnace according to the ratio of the exhaust gas flow area of the horizontal flue (i-1) and the horizontal flue (i + 1).

As described above, the exhaust system of the exhaust gas generated in the combustion chamber is connected to the two adjacent combustion chambers, and the change in the flow rate of the exhaust gas flowing between the front side and the rear side of the horizontal flue is connected to the horizontal flue. The combustion state of each of the small combustion chambers. As a result, three carbonization chambers (i), (i-1), (i)
The temperature distribution in the furnace length direction of +1) changes, and the burnout time in the furnace length direction changes. Therefore, accurate control is difficult unless the change in the temperature distribution in the furnace length direction due to the opening degree operation of the damper is quantitatively grasped. As a result, coal carbonization is not performed as intended, and the burnout time in the furnace length direction of the coking chamber differs, so that the coal at any position in the furnace length direction of the coking chamber is burned until the required storage time has elapsed. It is necessary to continue the process, which wastes fuel and causes furnace body damage such as deformation of the furnace lid.

[0011] Therefore, in order to make the temperature distribution in the furnace length direction of the coking chamber proper, conventionally, when extruding carbonized coke, the furnace wall temperature in the furnace direction of the coking chamber is measured by a furnace wall thermometer provided in the extruder. Skilled workers repeat the damper opening adjustment based on experience to obtain a proper temperature distribution, so that the distribution is measured and the furnace wall temperature distribution in the furnace length direction is made an appropriate distribution based on the measurement result. ing.

[0012]

However, such a conventional method requires a skilled worker, and the opening and closing operations of the damper vary depending on the experience and skill of the worker. The temperature distribution in the furnace length direction was affected by this, and the burnout time varied in the furnace length direction, which was far from optimal furnace operation.

It should be noted that JP-A-3-247693 discloses that
Sole flew (horizontal flue) at the front and rear of the furnace,
A method for controlling a furnace length temperature distribution of a coke oven, which divides into an end flue system and a middle flue system, and installs a damping pressure adjusting damper in each of them to control a temperature distribution in a furnace length direction, is proposed. However, this control method is intended to control the temperature distribution in the furnace length direction in consideration of the thermal compensation of the end flue, and the characteristics of the coke oven, that is, the heat storage chamber, the carbonization chamber, and the combustion chamber are one. No consideration is given to the fact that they interfere with each other as a process and form a mutual interference system, and their control performance is limited.

Japanese Unexamined Patent Publication (Kokai) No. 63-238191 discloses a unit heating system comprising a heat storage chamber, a combustion chamber, and a carbonization chamber.
A temperature sensor such as a thermocouple is installed in the representative combustion chamber row of the furnace group composed of ~ 100 furnaces, and the pressure reduction of the furnace front side and the furnace rear side is adjusted so that the actual temperature distribution in the furnace length direction is maintained at the target temperature distribution. A method for controlling the temperature distribution of a coke oven for controlling the opening of a damper for a coke oven has been proposed.

However, in order to implement this control method, it is necessary to install temperature sensors in the furnace length direction of all the combustion chamber rows in the direction of the furnace group, which requires a large facility cost.
Also, in this control method, the above-mentioned Japanese Patent Laid-Open No.
Similar to the control method presented in Japanese Patent No. 47693,
No consideration is given to the characteristics of the coke oven, that is, the fact that the heat storage chamber, the carbonization chamber, and the combustion chamber interfere with each other as a single process and form a mutual interference system. There is.

The present invention has been made in view of such a situation, and the temperature distribution in the furnace length direction of the coking chamber is maintained at an appropriate distribution so that the burn-out time and the placing time in the furnace length direction are substantially the same. It is an object of the present invention to provide a method of controlling a furnace wall temperature taper of a coke oven which can save energy in a short time.

[0017]

According to a first aspect of the present invention, there is provided a coke oven wall temperature taper control method according to the first aspect of the present invention. A plurality of combustion chambers for heating are alternately provided in the furnace width direction, and a flow path for supplying fuel gas and air to each of the combustion chambers and a horizontal flue for passing exhaust gas discharged from each of the combustion chambers are provided. In the method of controlling the wall temperature taper of a coke oven having a rear damper provided at the end of the horizontal flue at the rear of the furnace and a front damper provided at the end of the horizontal flue at the front of the furnace,
When extruding the carbonized coke, the furnace wall temperature taper is detected from the furnace wall temperature distribution in the furnace length direction measured by the furnace wall thermometer provided in the extruder, and the standard deviation of the furnace wall temperature taper is used in advance. Calculate the exhaust gas discharge set flow area ratio for each carbonization chamber by restricting the magnitude of the control wall deviation of the furnace wall temperature taper between the determined target furnace wall temperature taper and the actual furnace wall temperature taper. The ratio of the exhaust gas discharge set flow area ratio of the horizontal flue to minimize the variation of the horizontal flue exhaust gas discharge flow area ratio from the ratio, and the opening degree of the rear and front dampers based on the exhaust gas discharge set flow area ratio To determine. Here, the “exhaust gas discharge and distribution area ratio for each carbonization chamber” refers to the opening area ratio of these horizontal flues when three horizontal flues are related to one carbonization chamber,
The “exhaust gas discharge and distribution area ratio between horizontal stacks” refers to the opening area ratio between the rear damper on the rear side of the furnace and the front damper on the front side of the furnace.

That is, in the method of controlling the furnace wall temperature taper of the coke oven according to the present invention, the difference between the furnace wall temperature and the burn-out time has a linear relationship, and the difference in the burn-out time between the front side and the rear side of the furnace is reduced. It is made by paying attention to the fact that there is an appropriate temperature difference. As shown in FIG. 7, by appropriately maintaining the furnace wall temperature taper (furnace wall temperature difference) between the furnace front side and the furnace rear side, This is based on the finding that the burn-down time and the placing time in the furnace length direction of the coking chamber can be made substantially the same. In FIG. 7, the horizontal axis represents the furnace wall temperature taper (furnace wall temperature difference) between the front side and the rear side of the furnace, and the vertical axis represents the difference in the burnout time (T _max ) between the front side and the rear side of the furnace. ing.

According to a second aspect of the present invention, in the coke oven wall temperature taper control method according to the first aspect, the standard deviation is used as a dead zone of the oven wall temperature taper control deviation. .

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to FIGS. 1 is an external view of a main part of a coke oven, FIG. 2 is an explanatory diagram of a main part of a flow path of the coke oven, FIG. 3 is a cross-sectional view showing an arrangement of a carbonization chamber and an extruder, and FIG. FIG. 5 is a schematic diagram of an exhaust system of exhaust gas generated in the combustion chamber. FIG. 5 is a block diagram showing a structure of a furnace wall temperature taper control system in a method of controlling a furnace wall temperature taper of a coke oven according to one embodiment of the present invention. FIG. 3 is a diagram showing a step response of a furnace wall temperature taper to a carbonization cycle.

FIG. 1 shows the internal structure of the coke oven in a partially sectioned state for easy understanding.

As shown in FIG. 1, a coking chamber 1 into which coal is charged and a combustion chamber 2 for heating the coking chamber 1 from both sides are alternately arranged in the Z-axis direction (furnace width direction). , Each of which is provided in large numbers. Each combustion chamber 2 is formed from a plurality of small combustion chambers connected in the furnace length direction.
As shown in FIGS. 1 and 2, a heat storage chamber 3 is provided below the carbonization chamber 1. The heat storage chamber 3 guides supplied fuel gas and air to the combustion chamber 2, and exhaust gas generated by combustion. To the flue 4 via the horizontal flue 7. Therefore,
The heat storage chamber 3 through which the high-temperature exhaust gas passes is heated thereby to accumulate heat, so that the fuel gas and the air guided to the combustion chamber 2 are preliminarily heated in the heat storage chamber 3 and easily burn. In the present embodiment, the flow path through which the fuel gas and the air pass and the horizontal flue 7 through which the exhaust gas passes are alternately switched at a control cycle of 30 minutes. In FIG. 1, reference numeral 5 denotes a furnace lid.

[0023] As shown in FIG.
Coal that has been charged into the carbonization chambers 1 through a and has been carbonized, that is, coke that has been carbonized, is extruded from the rear side of the furnace by an extruder 20 shown in FIG. 3, and is taken out of the furnace from the furnace front side. The ram of the extruder 20 is provided with three optical fibers 21 in the furnace height direction in order to measure the furnace wall temperature in the coking chamber 1 at a position corresponding to each small combustion chamber in the furnace length direction. . These optical fibers 21 are provided for guiding the light at the ram tip 20 a to the outside of the furnace. The light guided to the outside of the furnace by the optical fibers 21 is a radiation temperature (not shown) provided on the extruder 20. Incident on the meter. The radiation thermometer and the optical fiber 21 form a furnace wall thermometer. The extruder 20 is provided with a ram movement amount detector (not shown) that outputs a signal each time the ram tip 20a moves by a predetermined amount.

Therefore, the temperature measuring position is detected based on the signal output from the ram movement detector, and the optical fiber 21 is switched every time the temperature measuring position becomes a predetermined position adjacent to each small combustion chamber in the furnace length direction. By measuring the temperature with the radiation thermometer used, the furnace wall temperature distribution in the furnace length direction of the coking chamber can be measured.

Next, the configuration of the main part of the flow path of the coke oven will be described.
This will be described with reference to FIG. The flow rate of the air 11 is adjusted by the air cock 12, and the switching cock 13, the horizontal pipe 8a
And, it is supplied to the heat storage chamber 3 and the combustion chamber 2 through the under jet pipe 9a. The fuel gas (MG) 14, which is a mixture of coke gas COG and blast furnace gas BFG having different calories, is adjusted in flow rate by a fuel gas cock 15, and passes through a switching cock 16, a horizontal pipe 8g, and an under jet pipe 9g to store heat in the heat storage chamber 3. From the combustion chamber 2.

The air flow rate and the fuel gas flow rate supplied to the furnace group constituted by collecting 50 to 100 unit heating systems including the carbonization chamber 1, the combustion chamber 2 and the heat storage chamber 3 are controlled by flow controllers 17 and 18.
Is adjusted by the flow rate. These flow controllers 17, 1
In 8, these set flow rates (target flow rates) are controlled by a process computer (not shown) to adjust the flow rates.
The exhaust gas generated in the combustion chamber 2 passes through a horizontal flue (sole flue portion) 7 and opens dampers (waist dampers) 6a and 6b which are one example of a front damper and a rear damper provided on the rear side and the front side of the furnace. The flow rate is distributed to the front side of the furnace and the rear side of the furnace according to the ratio of the exhaust gas discharge and circulation area determined by the degree, and is discharged to the flue 4 through the dampers 6a and 6b.
Actuators are connected to the dampers 6a, 6b, respectively, and the opening of the dampers 6a, 6b can be adjusted by the operation of these actuators. These actuators are operated by a process computer (not shown) to set these opening degrees (target opening degrees).
Is controlled to adjust each damper opening.

The structure of the furnace wall temperature taper control system according to the present invention will be described with reference to FIG. A furnace wall temperature taper control system shown in FIG. 5 is constructed in the process computer. The process computer adjusts and controls the degree of opening of each damper 6a, 6b according to the processing procedure described below after the completion of the charging of coal in each coking chamber. Note that the numbers in the circles at the upper left of each block shown in FIG. 5 indicate processing steps described below.

(Step 1) The furnace wall temperature taper is detected from the furnace wall temperature distribution in the furnace length direction measured when extruding the coke that has been carbonized.

The method of detecting the furnace wall temperature taper is as follows: 1) As described above, the temperature measurement position is detected based on the signal output from the ram displacement detector, and the temperature measurement position is set in each small combustion chamber in the furnace length direction. Each time a predetermined position adjacent to the position is reached, the temperature of the furnace wall at that time is measured with a radiation thermometer using three optical fibers 21, and the temperature distribution in the furnace height direction (upper, middle, lower) is determined. I do. 2) Fit a primary straight line to the measured furnace wall temperature distribution data. 3) The inclination of the linear line, that is, the temperature in front of the furnace is θ
_CS, the furnace rear-side temperature as θ _PS, furnace wall temperature taper Δθ
Δθ = θ _CS −θ _PS (1) is detected.

(Step 2) Using the furnace wall temperature taper Δθ detected in Step 1, a standard deviation σ with respect to the furnace core average furnace wall temperature taper is calculated, and this standard deviation σ is calculated as the furnace wall temperature taper control deviation (( Target furnace wall temperature taper)
(Actual furnace wall temperature taper)).

(Step 3) A deviation between a predetermined target furnace wall temperature taper and an actual furnace wall temperature taper is obtained, and the magnitude of the deviation is restricted by the dead zone set in Step 2, thereby obtaining a furnace wall temperature taper control deviation. Ask for. Assuming that the target furnace wall temperature taper is Δθ _{, ref} , the actual furnace wall temperature taper is Δθ _{, i} , and the standard deviation of the furnace wall temperature taper is σ, C _i = Δθ _{, ref} −Δθ _{, i} . as · (2), a deviation C _i between the target furnace wall temperature taper and actual furnace wall temperature tapered, | C _i | when ≦ sigma, when _{E i = 0 C i> σ} , E i = C i When −σ C _i <−σ, the magnitude of the deviation C _i is restricted by E _i = C _i + σ (3) to determine the furnace wall temperature taper control deviation E _i . Here, the subscript i represents the carbonization chamber number.

(Step 4) From the carbonization cycle of the horizontal flue (from charging coal to extruding coke), calculate the average carbonization chamber exhaust gas discharge and circulation area ratio from the carbonization chamber average. Based on FIG. 4 schematically showing the heating system of the coke oven, as described above, the exhaust gas generated in both combustion chambers (i) and (i + 1) of the carbonization chamber (i) is horizontal in the first half cycle of combustion. According to the flue gas discharge / circulation area ratio of the flue (i), the flow rate is distributed between the front side and the rear side of the furnace, and in the latter half cycle, the ratio of the flue gas discharge / circulation area of the horizontal flue (i-1) and the horizontal flue (i + 1) Thus, the flow rate is distributed between the furnace front side and the furnace rear side. Therefore, horizontal flue (i-
1), (i), and (i + 1), the average ratio of the exhaust gas discharge / circulation area of each dry distillation cycle is SR _i−1 , SR _i , and SR _{i + 1.
i is obtained} by DR _i = 0.5 × SR _i + 0.25 × (SR _i-1 + SR _{i + 1} ) (4)

(Step 5) Using the furnace wall temperature taper control deviation obtained in step 3, calculate the exhaust gas discharge set flow area ratio for each carbonization chamber such that the actual furnace wall temperature taper is maintained at the target furnace wall temperature taper. .

FIG. 6 is a diagram showing the step response of the furnace wall temperature taper when the ratio of exhaust gas discharge and circulation area per carbonization chamber is changed stepwise in the dry distillation cycle 0 shown on the horizontal axis.
In FIG. 6, the furnace wall temperature taper is an S-shaped step response without overshoot. Therefore, the discrete-time PI control (proportional-integral control) is applied to the calculation of the exhaust gas discharge set distribution area ratio for each carbonization chamber such that the actual furnace wall temperature taper is maintained at the target furnace wall temperature taper. The calculation of the exhaust gas discharge setting flow area ratio for each carbonization chamber is as follows: 1) Using the furnace wall temperature taper control deviation determined in step 3, the adjusted flow rate ΔDR _i of the exhaust gas discharge flow area ratio for each carbonization chamber
ΔDR _i = KP × [E _i (k) −E _i (k−1)] + KI × E _i (k) (5) Here, KP is a discrete-time proportional control gain, and KI is a discrete-time integral control gain.
Based on the step response of the furnace wall temperature taper shown in (1), the furnace wall temperature taper control is performed, and the control gain is adjusted to determine them. K represents a carbonization cycle.

2) Using the allowable maximum value ΔDR _max of the adjusted flow rate of the exhaust gas discharge / circulation area ratio for each carbonization chamber, the magnitude of the adjusted flow rate ΔDR _i calculated in 1) is restricted. | ΔDR _i | ≦ ΔDR
_max and those not satisfied are set to | ΔDR _i | = ΔDR _max . 3) using dry distillation cycle average coking chamber for each exhaust gas discharge flow area ratio DR _i obtained in Step _{4, DR i, SV = DR} i + ΔDR i ················ ( 6) Calculate the exhaust gas discharge set distribution area ratio DRi _{, SV} for each carbonization chamber so as to maintain the actual furnace wall temperature taper at the target furnace wall temperature taper.

(Step 6) The set flow area ratio DR _{i, SV of the} exhaust gas discharge per carbonization chamber calculated in step 5 up to now
From this, an exhaust gas discharge set distribution area ratio of the horizontal flue that minimizes the variation in the exhaust gas discharge distribution area ratio between the horizontal flue is determined. The exhaust gas discharge setting distribution area ratio that realizes the exhaust gas discharge setting distribution area ratio for each carbonization chamber that maintains the actual furnace wall temperature taper at the target furnace wall temperature taper includes the carbonization chamber realized by the exhaust gas discharge setting distribution area ratio. The exhaust gas discharge / circulation area ratio should be as close as possible to the exhaust gas discharge set distribution area ratio DRi _{, SV} for each carbonization chamber calculated by equation (6), and the load on each heat storage chamber should be as uniform as possible. That is,
It is required that the variation of the set flow area ratio between the flue gas and the horizontal flue be as small as possible. The following equation (7) can be used as the evaluation function.

[0037]

(Equation 1)

Here, maxf is the number of combustion chambers in the furnace group (= the number of carbonized chambers in the furnace group + 1), DR _{i, SV} is the ratio of the set flow area of exhaust gas discharge per carbonization chamber in the carbonization chamber (i), SR _{i, SV} Is the set exhaust gas discharge area ratio of the horizontal flue (i) corresponding to the carbonization chamber (i),
Ja is the error with respect to the distribution area ratio of flue gas emission per carbonization chamber, Jb is the evaluation of the variation in the distribution area ratio of flue gas discharge between horizontal flue, and ω is the weighted evaluation value of Ja and Jb It is. The set flow area ratio of exhaust gas discharge is determined by simultaneously solving the following equation (8) so as to minimize the evaluation values of Ja and Jb shown in the above equation (7).

[0039]

(Equation 2)

For example, when 55 furnaces are assembled to form one furnace group, it is given by the following equation (9).

[0041]

(Equation 3)

Here, the coefficient matrix G shown in the equation (9) is a general matrix. In order to obtain the set flow area ratio of the exhaust gas emission from the horizontal flue, the inverse matrix calculation method of the general matrix is used to calculate SR _SV = ( G ^T × G ^-1 ) × G ^T × DR _SV ... (10) Here, T on the right shoulder means transposition, and -1 means an inverse matrix. In addition, SR _SV is an exhaust gas discharge setting distribution area ratio vector of the horizontal flue, and DR _SV is an exhaust gas discharge setting distribution area ratio vector of each carbonization chamber.

(Step 7) A predetermined calculation is performed based on the ratio of the set area of exhaust gas discharge in the horizontal flue and the area of exhaust gas discharge and flow on the front and rear sides of the horizontal flue used up to the current control. Of the dampers provided on the front side and the rear side of the furnace are determined and determined.

(Step 8) Output the set opening of each damper to an actuator for adjusting the opening of the damper.
Adjust the damper opening. By controlling the opening degree of the damper provided on the front side and the rear side of the furnace of each horizontal flue according to the deviation between the target furnace wall temperature taper and the actual furnace wall temperature taper by the above control, the carbonization chamber By keeping the temperature distribution in the furnace length direction at an appropriate distribution, it is possible to make the burn-out time and the placing time in the furnace length direction almost the same time. In the description of the present invention, the opening of the dampers provided on the front side and the rear side of the furnace is adjusted by automatic control. However, for example, those set values are provided to an operator by an operation guide. Then, those adjustments may be made by an operator.

[0045]

EXAMPLES In order to verify the effects of the present invention, a soft simulator for simulating the temperature field behavior of the coke oven described above was constructed and a soft evaluation experiment was performed. FIG. 8 shows the results of the simulation of the control of the furnace wall temperature taper. The horizontal axis of the drawing is the carbonization cycle, and FIGS. 8 (a), (b) and (c) are the furnace wall temperature tapers on the front side and the rear side of the furnace, and the target temperature taper is shown by a broken line. Shown by solid line. On the other hand, FIGS. 9 (d), (e), and (f) show the distribution of burn-out time (T _max ) in the furnace length direction when the furnace wall temperature taper control is performed. Is indicated by a broken line, and the burn-out time in front of the furnace is indicated by a solid line.

8 (a), 8 (b) and 8 (c), according to the method for controlling the furnace wall temperature taper of the coke oven according to one embodiment of the present invention, the furnace wall temperature taper is controlled to start up ( It can be seen that, after the carbonization cycle 1), the target value was set to the target value with almost sufficient accuracy in about 10 cycles. FIG.
According to (d), (e) and (f), according to the method of controlling the furnace wall temperature taper of the coke oven according to one embodiment of the present invention,
The difference in the burn-out time (T _max ) between the front side and the rear side of the furnace decreases with the deviation from the target value of the furnace wall temperature taper. It turns out that it is the same time.

[0047]

As described above, the method for controlling the furnace wall temperature taper of the coke oven according to the first and second aspects of the present invention provides a method for controlling the furnace wall temperature taper deviation between the target furnace wall temperature taper and the actual furnace wall temperature taper. Accordingly, the opening degree of the front and rear dampers provided on the front side and the rear side of the furnace in each coking chamber is adjusted, so that the temperature distribution in the furnace length direction of the coking chamber is maintained at an appropriate distribution, and the fire in the furnace length direction is maintained. The falling time and the placing time can be made substantially the same time, so that unnecessary fuel consumption can be reduced, and the cause of damage to the furnace body such as deformation of the furnace lid can be avoided, and the furnace life can be extended. In the coke oven wall temperature taper control method according to claim 2, the standard deviation is used as a dead zone of the furnace wall temperature taper control deviation, so that the amount of adjustment of the opening of the front and rear dampers can be adjusted. As a result, the size of the actuator can be reduced.

[Brief description of the drawings]

FIG. 1 is an external view of a main part of a coke oven.

FIG. 2 is an explanatory diagram of a configuration of a main part of a flow path of a coke oven.

FIG. 3 is a sectional view showing an arrangement of a carbonization chamber and an extruder.

FIG. 4 is a schematic diagram of an exhaust system of exhaust gas generated in a combustion chamber.

FIG. 5 is a block diagram showing a structure of a furnace wall temperature taper control system in a method for controlling a furnace wall temperature taper of a coke oven according to one embodiment of the present invention.

FIG. 6 is a diagram showing a step response of a furnace wall temperature taper to a carbonization cycle.

FIG. 7 is a graph showing a result of a simulation performed using a coke oven temperature field simulator and showing a relationship between a furnace wall temperature taper on a furnace front side and a furnace wall side on a furnace rear side and a burn-out time difference.

FIG. 8 is a graph showing an example of the present invention using a coke oven temperature field simulator.

FIG. 9 is a graph showing an example of the present invention using a coke oven temperature field simulator.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Coalization chamber 1a Coal loading inlet 2 Combustion chamber 3 Thermal storage chamber 4 Flue stack 5 Furnace lid 6a Damper (rearward damper) 6b Damper (front damper) 7 Horizontal flue 8a Horizontal pipe 8g Horizontal pipe 9a Under jet pipe 9g Under jet pipe 11 Air 12 Air cock 13 Switching cock 14 Fuel gas 15 Fuel gas cock 16 Switching cock 17 Flow controller 18 Flow controller 20 Extruder 20a Ram tip 21 Optical fiber

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Keihachiro Tanaka 1-9-4 Nihonbashi Honcho, Chuo-ku, Tokyo Inside Nippon Steel Elex Co., Ltd.

Claims (2)

[Claims] 1. A plurality of carbonization chambers for charging and dry-distilling coal, and combustion chambers for heating the carbonization chambers from both sides are alternately provided in a furnace width direction. A rear damper is provided at the end of the horizontal flue at the rear of the furnace and at the end of the horizontal flue at the front of the furnace, including a flow path for supplying air and a horizontal flue for passing exhaust gas discharged from each of the combustion chambers. In the method of controlling the furnace wall temperature taper of a coke oven having a front damper, the furnace wall temperature taper is determined from the furnace wall temperature distribution in the coking chamber furnace length direction measured by a furnace wall thermometer provided in an extruder when extruding carbonized coke. Detecting and standardizing the furnace wall temperature taper using the standard deviation of the furnace wall temperature taper and restricting the magnitude of the furnace wall temperature taper control deviation between the target furnace wall temperature taper and the actual furnace wall temperature taper, and setting the exhaust gas discharge setting distribution for each carbonization chamber. Calculate the area ratio and calculate the carbonization The flue gas discharge set distribution area ratio of the horizontal flue that minimizes the variation of the flue gas discharge distribution area ratio between horizontal flue is determined from the exhaust gas discharge set distribution area ratio per room,
A method for controlling a temperature of a furnace wall taper of a coke oven, comprising determining an opening degree of each of the rear and front dampers based on the set flow area ratio of the exhaust gas discharge. 2. The system according to claim 1, wherein the standard deviation is used as a dead zone of the furnace wall temperature taper control deviation.
A method for controlling a furnace wall temperature taper of a coke oven as described in the above.