JPS59147077A - Method for controlling temperature of coke oven - Google Patents

Abstract

PURPOSE:To control the temperature of a coke oven in high accuracy, and to stabilize the operation of the oven, by controlling the heat quantity introduced to the oven at a constant level as far as possible. CONSTITUTION:A number of combustion chambers 4R and carbonization chambers 4C are arranged alternately, and each combustion chamber is supplied with fuel gas from the main fuel pipe 1 through the branch pipe 2, and at the same time, supplied with combustion air through the air valves 5R, 5C and the regenerator 7R. The waste gas generated by combustion is discharged to the common flue through the waste heat valve 10 and the regenerator 7R. The pressure P1 in the main fuel pipe is controlled so as to adjust the difference between P1 and the pressure in the common flue P2 (DELTAPG) to the value designated by the formula (DELTAPSG is the preset pressure difference between P1 and P2 ; T0G is standard absolute temperature of fuel gas; T1G is measured absolute temperature of fuel gas). The average temperature of the coke oven group is determined by measuring the temperatures of plural combustion chambers, and the feeding time of the fuel gas to the combustion chamber is controlled so as to equalize the average temperature to the preset temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling combustion in a coke oven, and more specifically, the present invention relates to a method for controlling combustion in a coke oven, and more specifically, the coke is controlled so that the amount of heat input to the coke oven is kept as constant as possible.

As is well known, a coke oven consists of a large number of combustion chambers and carbonization chambers arranged alternately, and each combustion chamber is supplied with fuel gas through a branch pipe from a fuel gas main pipe, and an air valve and Combustion air is supplied through the regenerator, and combustion waste gas from each combustion chamber is directed to a common flue through the waste heat valve and the regenerator.

Therefore, in the operation of a coke oven, in order to obtain coke with a high quality of 1110%, and furthermore, in order to save energy and energy, it is necessary to increase the l'! !
: It is necessary to manage the combustion of the coke oven so that the temperature of the coke oven is always at the target temperature, but the temperature of the coke oven group is
Accurate combustion management is not always easy because it fluctuates due to fluctuations in the fuel gas supplied to the combustion chamber, the amount of air for combustion, and the moisture content of the charged coal.

For example, the following methods are conventionally known as combustion control methods for coke ovens.

First, it is a prerequisite for combustion management. Methods for controlling fuel gas and combustion air include a flow rate control method, a pressure control method, and the like. Explaining these methods in terms of fuel gas, the former controls the supply amount by a flow rate control valve installed at the fuel main pressure, and the latter controls the supply amount between the fuel main pressure and the common flue pressure. The next step is to measure the temperature of multiple combustion chambers, calculate the average temperature of the coke oven group, and compare the average temperature with the set temperature. A method is known in which the amount of fuel sludge supplied is controlled using any of the methods described above so that .

However, the current state of the art is that such conventionally known methods have not yet achieved satisfactory results, even though strict control is performed.

In view of the above-mentioned circumstances, the inventors of the present invention have conducted intensive studies to provide a more accurate coke oven combustion management method. Even if a pressure control method is adopted, which is superior in that the amount of fuel gas supplied to other combustion chambers does not fluctuate, there is a considerable daily fluctuation, and therefore, as a prerequisite for coke oven temperature control, We learned that it is necessary to keep the amount of heat input as constant as possible.

The present inventors previously proposed a method for controlling uniform heat input into a coke oven in Japanese Patent Application No. Sho kA-/311Sata/, and the present invention is an improvement of this basic invention. The temperature of the coke oven is controlled using a special method.

The present invention will now be described in detail with reference to the accompanying drawings.

First, the uniform heat input control to the coke oven, which is the premise of the present invention, will be explained.

FIG. 1 is a schematic cross-sectional view of a conventional λ-split combustion type Karl Steel coke oven.

In a coke oven, a large number of combustion chambers and carbonization chambers are arranged alternately to form one furnace group, and the furnace group is divided into an extrusion side (R) and a coke f[ll+(0)].

Fuel gas enters the gas duct (3R) from the extrusion side fuel main pipe (/R) through each branch pipe (2R) and three-way cock (-2R'), and is distributed to each combustion chamber (IIR) K. At this time, the supply of fuel gas to the coke side (0) is stopped by the three-way cock (, 2C').

On the other hand, combustion air is supplied through each air valve (&R) and sole flue (AR), and is preheated while passing through a heat storage chamber (7R). after that.

From each air duct 1- (gR), the air is divided into several stages (9 stages in FIG. 1) in the vertical direction and is supplied to each combustion chamber (<=R). Here, the fuel gas and the combustion air come into contact and the fuel gas is combusted.

The combustion waste gas from each combustion v(+R) is transferred to the horizontal flue (9)
(g:o), the air passes through the heat storage chamber and is discharged from the chimney (the common flue and chimney are not shown in FIG. 1).

These gas flows are switched every 20 minutes by a so-called heating switching operation.

The outline of the heating switching operation will be explained as follows based on Figure 1. This figure is a conceptual diagram showing the operation of the band iron in the heating switching operation.

In other words, each air valve (R
,,tG) and waste heat valve (lOR9IOC) are connected,
In addition, each three-way cock (2R'
, , 20') are connected. These iron bands are operated by a drive control mechanism (10θ), and the air valves (, tR) and three-way cocks (,!R') of each combustion chamber on the extrusion side and each waste heat valve (IOC) on the coke side are opened. And conversely, the air valve (40) and three-way cock (, 2) of each combustion chamber on the coke side
The valve opening/closing operation in which the waste heat valves (10R) and the extrusion side waste heat valves (10R) are closed is performed alternately every 20 minutes.

In general, the COG band iron (B) is activated slightly later than the air-gas band iron (A), and the fuel is turned on after combustion air has been reliably supplied. Gas supply is now available.

The coke oven is constructed as described above, and the flow of gas is shown in FIG. 3. That is, the fuel gas (b) passes through the fuel main pipe (1) and enters the combustion chamber (
It is combusted by the supplied combustion air (a) and becomes combustion waste gas (C1) in the common flue (/
2) and is discharged from the chimney (/3).

In such a coke oven, the method of the present invention is based on the differential pressure (△
The fuel main pressure (P, ) is controlled so that po) becomes a value expressed by the following equation (1). - In the above formula, ΔPea is the set differential pressure between the fuel main pressure and the common flue pressure, and any value can be adopted, but in general, it is the design pressure of the fuel gas burner or past operating results. etc., and is appropriately determined by t~. ``OG is the reference absolute temperature of fuel gas, and although it can be arbitrarily determined, the average value of past actual temperatures is usually adopted.
IG is the actually measured absolute temperature of the fuel gas, and is a value continuously measured by an appropriate means.

Control the fuel main pressure (PI) so that the differential pressure (ΔpG) between the fuel main pressure (Pl) and the common flue pressure (P, ) becomes the value expressed by the control formula in (1) above. means to correct the density change due to temperature of the fuel gas and to always keep the mass flow rate (or volumetric flow rate converted to standard conditions) of the fuel gas constant.

In the present invention, the amount of heat input to the coke oven is made as uniform as possible in this way, but when coke oven gas is used as the fuel gas, the above (
It is preferable to use the following (/') in place of the control equation 1) because even more accurate heat input can be achieved.

In the above formula, co is the standard calorie of the fuel coke oven gas, and means the average calorie of the coke oven gas. 0
1 is the actually measured calorie of the same gas, which is a value continuously measured by a calorie meter.

The significance of using the control equation (/') above is to achieve uniform heat input by taking into account changes in the composition of the fuel coke oven gas (in other words, changes in calories). This is unnecessary when using a mixed gas of coke oven gas and blast furnace gas that has been mixed and adjusted so that the calorie content is constant.

FIG. 7 is a graph showing data showing the effect of the uniform heat input control of the present invention, and showing a change over time in the temperature deviation from the reference firing temperature in the lower part of the combustion chamber. The vertical axis is temperature (tl
'), and the horizontal axis shows the date and time. In the figure, the solid line without a plot is the result of the conventional method, and the dotted line is the result of the method of the present invention in which fuel gas is controlled according to the control formula (1),
Further, the solid line connecting the plots is the result of the method of the present invention in which the fuel gas was controlled according to the control formula (/').

As is clear from Figure 7, when using the conventional method, the temperature inside the combustion chamber fluctuates considerably on either side of the reference combustion temperature (indicated as OC in the Figure). However, in the case of the method of the present invention, the change over time is extremely close to the standard firing temperature, and it can be seen that the amount of heat input to the coke oven is always almost constant. The portion exceeding the standard firing temperature (the shaded portion in Fig. 7) means a loss of fuel gas, but in the case of the method of the present invention, as is clear from Fig. 7, this portion is reduced by a small amount. (Therefore, it is also advantageous from the point of view of energy saving.

tr t? Incidentally, the degree of temperature difference between the method of the present invention and the conventional method is specifically shown as follows using the δ value.

Conventional method δ=A, A multi-invention method (in case of control formula (1)) δ-ko1
gchi Same as above (in case of control formula (/')) δ=7.
Section 3 The method of controlling combustion in a coke oven according to the present invention is to control the amount of fuel gas supplied as described above, thereby making the amount of heat input to the coke oven as uniform as possible. However, the contribution ratio of combustion air to heat input is extremely small, and therefore, in the above-mentioned uniform heat input control, fluctuations in mass flow rate due to temperature changes of combustion air can be ignored, but combustion efficiency is increased. In order to achieve even more effective energy savings, it is necessary to perform similar control on combustion air in addition to fuel gas control.

The combustion air is controlled by the atmospheric pressure near the air valve (
Differential pressure (△PA) between Po) and common flue pressure (P2)
This can be easily implemented by controlling the common flue pressure (P2) so that P2 becomes the value expressed by the following equation (c).

In the above formula, ΔPEA is the set differential pressure between the atmospheric pressure near the air valve and the common flue pressure, and any value can be adopted, but it is generally the design pressure of the combustion air burner or the past It will be decided as appropriate, taking into consideration the operational performance of the company. TOA is the reference absolute temperature of combustion air, and usually the average temperature of past results is adopted. T and □ are measured absolute temperatures of the combustion air, which are values continuously measured by appropriate means.

In the present invention, the density change due to temperature of the combustion air is corrected in this way, and the mass flow rate of the combustion air is made constant.
By correcting A by the oxygen concentration in the combustion waste gas (r), it is possible to eliminate fluctuations in the mass flow rate due to changes in factors other than the humidity and temperature of the combustion air, resulting in even higher combustion efficiency. be able to.

Therefore, the above-mentioned correction based on the oxygen concentration of ΔPg is performed by obtaining the relational data between the two in advance, measuring the oxygen concentration in the sequential gas, and using the measured value and the relational data as ΔP1.
This is done by correcting lA, but the lowest value in the moving average value is calculated from the measurement results within the operation time divided at arbitrary equal intervals, and the obtained lowest value is used as the contradictory element concentration and the above-mentioned relationship data. It is preferable to determine ΔPIIA from ΔPt1A and use the ΔPt1A to control the combustion air during the next operation time.

Figure 3 is a graph showing an enlarged view of the change over time in the oxygen concentration in the combustion waste gas in order to explain the concept of the moving average value. In the figure, the vertical axis shows the oxygen concentration (vol, h), the horizontal axis shows the time (8 ec,), and the stepped steps represent the sampling period (-) and sampling time (
y).

The sampling period (-), sampling time (y), and number of samples within the sampling time can be determined arbitrarily, taking into account the analytical characteristics of the oxygen concentration in the waste gas, which is affected by the structure of the coke oven, basic operating conditions, etc. For example, the sampling period is determined! From the range of -AO seconds, the sampling time is from the range of /-/0 minutes,
Further, the number of samplings can be selected from the range of 10 to /θθ.

Figure 5 shows that within an arbitrary operation time (A+ rAt...
This is a graph plotting the moving average value of the oxygen concentration for each step (the moving average value in step (1) in Figure 7 corresponds to the plot (1) in Figure S). The axis shows the oxygen concentration (vol, %), and the horizontal axis shows the operating time band (HR). A certain amount of operation time is required to obtain an appropriate moving average value, and furthermore, if the operation time is too short, the effect of the correction of ΔPIIA by the oxygen concentration will not appear, so these should be taken into account. Although it is determined as appropriate, it is usually in the range of 30 minutes to a hour. However, in the present invention, the lowest value of the moving average value (the value marked with a horizontal line in the figure) in an arbitrary operation time band (for example, A+ in Figure N) is determined, and ΔP13A is calculated based on this value. The correction value is applied to the next operation time band (for example, A
This method is used to control the combustion air in step 2).

Correction using the oxygen concentration trap of ΔPFIA is performed based on relational data between the two obtained in advance; for example, relational data as shown in FIG. 4 may be employed. No. 6
The figure shows the relationship between the two, with the vertical axis representing the correction value (Pα) of ΔPIIA and the horizontal axis representing the oxygen concentration.
The value is set as Pα and added to ΔPI'lA.

FIG. 3 shows data showing the effect of the present invention on combustion efficiency, and is a graph showing changes over time in the oxygen concentration in the combustion waste gas. The vertical axis shows the oxygen concentration (VOl, CH), and the horizontal axis shows the date and time. In the figure.

The solid line without plots is the result of the conventional method, the dotted line is the result of the method of the present invention in which combustion air is controlled according to the control formula (2), and the solid line connecting the plots is the result of the control formula ( , 2) is the result of the method of the present invention when ΔP[]A in 2) is corrected by the oxygen concentration in the waste gas.

As is clear from Figure 3, when using the conventional method, the oxygen concentration in the waste gas is the value specified as the appropriate oxygen concentration (
In Fig. 3, left v01. H) Yoshi also fluctuates considerably on the excessive side.

In other words, combustion of fuel gas is carried out by supplying an appropriate amount of combustion air, which is the theoretical amount plus a certain excess amount, but in the conventional method in which the mass flow rate of combustion air fluctuates, the amount of supplied air In order to prevent the generation of black smoke that occurs when the amount of air drops below the appropriate amount, air is always supplied in excess of the appropriate amount.

On the other hand, in the case of the method of the present invention, the value changes close to the appropriate oxygen concentration, and in particular, it can be seen that the method of the present invention in which ΔPIIA is corrected almost matches the appropriate oxygen concentration. The part i exceeding the appropriate oxygen concentration corresponds to an unnecessary amount of air, but in the method of the present invention, this part is extremely small, and therefore the combustion efficiency is extremely high.

The method of the present invention measures the temperature of a plurality of combustion chambers in a coke oven controlled so that the amount of heat input to the coke oven is as constant as possible as described above, and calculates the average temperature of the coke oven group. The main feature is that the supply time of combustion gas to the combustion chamber is controlled so that the calculated average temperature and the set temperature of the coke oven group are equal.

By doing so, it is possible to eliminate variations in the coke oven temperature due to changes in the moisture content of charged coal, etc., and achieve highly accurate combustion control.

The temperature of the combustion chamber can be easily measured, for example, by using a thermocouple inserted and fixed into the flue nozzle above the coke oven. It is necessary to measure the temperature of the combustion chamber.

That is, each combustion chamber of a coke oven is different due to the difference in the progress of the carbonization process between adjacent carbonization chambers. Therefore, it is necessary to measure the temperature in all combustion chambers (for example, between SO and IOO) of a coke oven group, or to measure an appropriate number of combustion chambers so that the average temperature of the coke oven group can be obtained by canceling out the fluctuations due to differences in the carbonization process. It is necessary to measure the temperature of the room.

As mentioned above, the average temperature of a coke oven group is obtained by measuring the temperature of multiple combustion chambers, but the temperature measurement in each combustion chamber is done by keeping the temperature measurement point, specifically the insertion position of the thermocouple, constant. It is preferable to carry out the measurement under the same conditions, and the average temperature may be calculated by processing each temperature measurement result or by serially synthesizing the outputs of thermocouples to directly obtain the average temperature. .

In the method of the present invention, the temperature of the coke oven is controlled by controlling the supply time of fuel gas to the combustion chamber so that the average temperature of the coke oven group measured as described above is equal to the set temperature of the coke oven group. Take control.

The outline of combustion switching in a coke oven has already been explained, but j′J
The detailed explanation according to the block diagram below is as follows;
) is started by opening the extrusion side waste heat valve (/(7)
R) extrusion side switching work that is completed by the "open" operation, and 1
The process is started by opening the extrusion side waste heat valve (lθR).
It is distinguished from the coke side switching operation which is completed by opening the coke side waste heat valve (/(70)), and these operations are normally repeated alternately at intervals of λθ minutes.

But is the fuel gas actually supplied by the woman? The time during which the combustion is performed is a specific time within the above 20 minutes, for example, on the extrusion side,
The method of the present invention controls this time, which is the time from opening to closing.

That is, in the present invention, data relating to increases and decreases in combustion time given to the temperature difference between the average temperature of the coke oven group and the set temperature is prepared in advance, and based on this relational data, a
It controls the production of the OG band iron, thereby controlling the supply time of fuel gas to the combustion chamber.

As the combustion time increase/decrease relationship data, for example, relationship data as shown in FIG. 9 can be used. In this figure, the temperature difference (C) is plotted on the horizontal axis, and the increase/decrease time (seconds) is plotted on the vertical axis, and the relationship between the two is expressed by the line 1a, which is f-%. Such data can be easily created based on past operational results and experience.

However, various methods can be adopted for measuring the temperature of the combustion chamber and controlling the combustion time, but usually, for example, it is inserted and fixed from each representative flue nozzle on the coke side and the extrusion side. The temperature measured by the thermocouple at an appropriate time during non-combustion, that is, during the period when combustion waste gas is flowing, is used as a value, and this result is used to calculate the next combustion time,
Therefore, when using the measured value on the coke side, it is necessary to control the fuel gas supply time to the combustion chamber on the coke side.

As described above, the method θ of the present invention involves controlling the supply time of fuel gas to the combustion chamber in a coke oven in which the amount of heat input to the coke oven is controlled to be as constant as possible. Specifically, these controls are performed using a computer,
For example, this can be done automatically by a table system as follows.

First, a fuel gas control system for controlling heat input into a coke oven will be explained based on the above-mentioned FIG. 3. For convenience, FIG. 3 shows the automatic control system on the extrusion side; therefore, in practice, exactly the same system is adopted on the coke side.

Install a pressure control valve (/su), a temperature detector (/3), a calorie detector (//;), and a pressure detector (/7) at appropriate positions in the fuel main pipe (/l). , common flue (/2)
Install a pressure detector (2/) at an appropriate position. In addition,
As the calorie detector (/A), for example, an automatic Junkers method is used, which burns a certain amount of fuel gas, heats water, and calculates the calorie value of the fuel gas based on the rate of increase in temperature. .

Using a calculator (7g), set differential pressure (ΔpH(+)
, standard feed temperature of fuel gas (To, ) and standard calorie
(00) in advance, and input the measurement result from the temperature detector (/event) into the actual measured absolute temperature signal (Tt.) and (7) from the calorie detector (/6). i1'l of
The II determination result is input as the measured calorie signal (C1). A computer is used to perform arithmetic processing using the control formula (/') K described above to calculate the differential pressure (Δp0) between the fuel main pressure and the common flue.

Pressure detector (/7) and (,!/
) and the deviation of both signals (ΔP
G), and calculate the deviation signal and the differential pressure (8P) from the computer.
G) Control the pressure and i14 valve (glue) so that the signal intensity matches.

Next, a control system for the combustion amount will be explained.

A pressure control valve (2θ) and an oxygen concentration meter (2, 2) are installed at appropriate positions in the common flue (/). On the other hand, a pressure detection ji (2/') is installed near the air valve. Calculator (7g)
The set differential pressure (△PIIA), reference temperature (ToA), and relationship data between the set differential pressure and oxygen concentration are stored in advance, and the results are measured using a thermometer (23) installed near the air valve!・Input 17 as the measured absolute temperature signal (TIA) of the combustion air. In the computer, the above control equation (,7
) to calculate the base PF (ΔPA) of the atmospheric pressure near the air valve and the common flue pressure. Input the measurement signals from the pressure detector (2/) and (s/') into the pressure regulating valve (2), and calculate the 1 degree difference (△PA) between both signals.
Calculate the deviation signal and the differential pressure (△PA) from the computer.
Pressure regulating valve (,20) so that the signal magnitudes match
control.

On the other hand, the measurement signal from the oxygen concentration meter (C2) is sent to the computer (7).
g), perform arithmetic processing to calculate the lowest moving average value within a predetermined operation time, and create a control formula from the obtained lowest oxygen concentration and pre-stored relationship data between set differential pressure and oxygen concentration. The set differential pressure (ΔP8A) in (2) is legally stored, and in the next operation time, the above-mentioned calculation process is performed using the set differential pressure to calculate the atmospheric pressure near the air valve and the common flue pressure. Calculate the differential pressure (ΔPA) of , and control the pressure regulating valve (2) accordingly.

Next, a control system for the fuel gas supply time will be explained based on the above-mentioned FIG. 1.

Several thermocouples (not shown in the figure) are inserted and fixed into each combustion chamber (4") on the extrusion side and each combustion chamber (4") on the coke side. 11 The constant results are converted into a computer (/
0 / ) are input continuously.

The calculator (/θ/) has 1. In advance? Data related to increases and decreases in baking time are stored, and the input actual measured temperature signal (, =
) to calculate the average temperature of the coke oven group,
The thickness and weight loss of the shade baking time are calculated from the first shift and the above related data.

The N4 dynamic control mechanism (10θ) controls the next combustion 1 according to the combustion time increase/decrease input signal (y) from the computer (/lλ/).
Switching work, for example, because the extrusion side is in a combustion state,
and control the time from opening to closing of the extrusion side cock (, 7R'). The drive control mechanism (100) receives the fuel from the computer (/θ/) in the same manner.

The supply time of fuel gas to the combustion chamber is controlled by sequentially controlling the time from the coke side cock (2C') Hi'l to the closing time according to the dawn time increase/decrease input signal sequence (γ).

As explained above, the method of the present invention controls the temperature of the coke oven after controlling the amount of heat input to the coke oven to be as constant as possible. For example, it is possible to obtain coke of stable quality, achieve energy savings, and achieve highly accurate combustion control in a coke oven.Therefore, the present invention makes a significant contribution to the field of coke production.

[Brief explanation of the drawing]

□ Fig. 7 is a schematic cross-sectional view of a Karl Steel coke oven. (d) shows the distribution branch pipe, (d) shows the combustion chamber, and (l) shows the waste heat valve. Fig. 2 is a conceptual diagram showing the operation of the band iron during heating switching work, and in the figure, (A) shows the air - Band iron for waste gas, (B)
is the band iron for COG, (10θ) is the drive control mechanism, (/θl
) indicates a calculator. Note that the same symbols as in FIG. 1 have the same meanings (the same applies to the following figures). FIG. 3 is a conceptual diagram showing the flow of gas, and in the figure (a
) indicates the flow of combustion air, (b) indicates the flow of fuel gas, (0) indicates the flow of combustion waste gas, and (/Y) indicates the common flue. Figure d: This is a graph showing an enlarged view of the change over time in the oxygen concentration in the combustion waste gas.
ol, h), and the horizontal axis shows time (sec,). -6,
,1,-,In the same figure, the step d, the sampling period (-) in the moving average value, and the sampling time (y
). Figures 1 and 2 are graphs showing the moving average value of oxygen concentration, in which the vertical axis represents the oxygen concentration (vol, h), and the horizontal axis i,
indicates the operation time () (R). FIG. 6 is a graph showing the oxygen concentration and the correction value (PEA) of ΔPBA. FIG. 7 is a graph showing the change in temperature deviation from the reference firing temperature at the lower part of the combustion chamber over time, and the vertical axis is the temperature (C
), and the horizontal axis shows the date and time. FIG. g is a graph showing the change over time in the oxygen concentration in the combustion waste gas, where the vertical axis shows the oxygen concentration and the horizontal axis shows the date and time. Figure 9 shows an example of data related to the increase/decrease in combustion time with respect to the temperature difference between the average temperature of the coke oven group and the set temperature. Shows the temperature difference (C). Applicant: Mitsubishi Chemical Industries, Ltd. Agent: Patent attorney: Yo Hase - (and 7 others) 2 Figure 10 / 3 Figure procedural amendment (self-motivated) 1 Indication of the case Showa Sg. Patent Application No. 223 and 2
No. 2 Name of the invention Coke oven temperature ill! 1
ift-11 method; 3 Supplementary ``Person who does E. Relationship between 11 cases Applicant (,59g) Mitsubishi Chemical Industries, Ltd., 1 agent 〒100 5 Subject of supplementation Seiwa°'s ``Details of the invention explanation”,
Published by II (5?11i King's content (11th specification, !? line λ from the bottom of page 751 et al. page 1)
B10 “Fuel scum temperature depends on IC...”
It means everything. '' to ``Mass flow rate of fuel gas (or volumetric flow rate converted to standard state)'f: Means to be kept constant.More preferably, correction for density change due to temperature of fuel gas is added.Density change When the above correction is made, the control equation (1) above is expressed as the following equation.'' )2) In the third to second lines from the bottom of page 2 of the specification, "means" is replaced with "means."More preferably, the change in density due to temperature of fuel coke oven gas It is a good idea to make a correction.If the density change is corrected, the above (11 control equation is expressed by the following equation) is corrected. 7 from the third row from the bottom
Line U is like this for combustion air...
In this way, the mass flow of the fuel air is made constant, and more preferably, the density change due to the temperature of the fuel air is controlled. It is advisable to add a correction amount.If the correction of the density change is added, the control equation (2) above is expressed by the following equation.

Claims (1)

[Claims] (1) A large number of combustion chambers and carbonization chambers are arranged alternately,
Fuel gas is supplied to each combustion chamber through a branch pipe from the main fuel pipe, and combustion air is also supplied through an air valve and a heat storage chamber, and combustion waste gas from each combustion chamber is supplied through a waste heat valve and a heat storage chamber. In a coke oven bank in which the fuel is discharged to a common flue through a heat storage chamber, ■The differential pressure (ΔPG) between the fuel main pressure (P, ) and the common flue pressure (P2) is as follows (1). The fuel main pressure (Pl) is controlled so as to be equal to the value expressed by the formula (where △PB
, -1 is the set pressure difference between the fuel main pressure and the common flue pressure -T
Reference absolute temperature of oa Fi fuel gas, TI! (l is the measured absolute temperature of the fuel gas) ■ Measure the temperature of multiple combustion chambers to calculate the average temperature of the coke oven group, and set the temperature so that the average temperature and the set temperature of the coke oven group are equal.