JP6209899B2 - Furnace port resistance calculation method, flue gas blowing amount calculation method, furnace pressure control device, furnace pressure control program, and furnace pressure control method of converter exhaust gas treatment device - Google Patents

Description

  The present invention relates to a furnace outlet resistance calculation method, an exhaust gas blowout amount calculation method, a furnace pressure control device, a furnace pressure control program, and a furnace pressure control method for a converter exhaust gas treatment device.

  The exhaust gas generated in the converter contains carbon monoxide, which is a combustible gas, at a high concentration, and can be used as a fuel. Moreover, in order to effectively utilize the converter exhaust gas generated intermittently according to the operation, a converter exhaust gas treatment device that is collected in a gas holder and temporarily stored is used.

  In the converter exhaust gas treatment device, in order to efficiently recover the exhaust gas, it is necessary to appropriately control the furnace pressure, which is the differential pressure between the furnace internal pressure and the atmospheric pressure. When the furnace pressure is positive, that is, when the furnace pressure is higher than atmospheric pressure, exhaust gas blows out from the furnace port of the converter, and the amount of exhaust gas recovered itself decreases. On the other hand, when the furnace pressure is negative, that is, when the furnace pressure is lower than the atmospheric pressure, air is sucked from the furnace port, and carbon monoxide is combusted by oxygen in the air, so carbon monoxide contained in the exhaust gas. The concentration of will decrease. Therefore, in order to efficiently recover exhaust gas containing carbon monoxide at a high concentration, it is necessary to control the furnace pressure to near zero.

  For example, Patent Document 1 and Patent Document 2 disclose a method of increasing the recovery amount and recovery rate of carbon monoxide contained in exhaust gas by controlling the furnace pressure by adjusting the opening of the damper. Further, feedback control such as PI (Proportional-Integral) control is adopted for these furnace pressure controls.

JP 2003-342628 A JP-A 61-56220 JP-A-11-287424

と表される。ここで、ｋは、スカートの高さに応じて変化する炉口とスカートとの間の流入抵抗であり、炉口抵抗と呼ばれる（例えば特許文献３を参照）。この炉口抵抗ｋは、転炉排ガス処理装置（プラント）の炉圧制御におけるゲインに直接関係するため、これを用いて、制御パラメータ（ＰＩ制御の比例ゲインや積分時間など）を変更しながらより効率的に炉圧を制御することができる。 By the way, if the furnace pressure is P0 and the amount of air sucked from the furnace port is Fin, the furnace pressure P0 is

It is expressed. Here, k is an inflow resistance between the furnace port and the skirt that changes according to the height of the skirt, and is called a furnace port resistance (see, for example, Patent Document 3). Since this furnace port resistance k is directly related to the gain in the furnace pressure control of the converter exhaust gas treatment device (plant), it can be used while changing the control parameters (proportional gain of PI control, integration time, etc.). The furnace pressure can be controlled efficiently.

  However, air suction from the furnace port occurs only when P0 <0. Therefore, when P0> 0, the furnace port resistance k cannot be obtained from the above equation (1), and the furnace port The resistance k cannot be used for furnace pressure control.

The main present invention for solving the above-mentioned problems is a method for calculating a furnace port resistance between a furnace port and a skirt in a converter exhaust gas treatment apparatus that collects exhaust gas generated in a converter in a gas holder, Concentration data obtained by measuring the concentration of the contained gas, and flow rate data obtained by measuring the exhaust gas flow rate before the measurement time of the concentration data for a first time corresponding to the measurement time difference between the gas concentration and the exhaust gas flow rate, The furnace pressure data obtained by measuring the furnace pressure, which is the difference between the furnace pressure and the atmospheric pressure, for the second time corresponding to the measurement time difference between the gas concentration and the furnace pressure before the measurement time of the concentration data. And when the furnace pressure data indicates air suction from the furnace port, based on the flow rate data and the concentration data, calculate the amount of air sucked from the furnace port, Previous furnace pressure data Based on the intake amount of air, calculates the furnace opening resistance, the furnace when the pressure data does not indicate the suction of air from the furnace port, the calculated throat resistance in the past, the furnace opening a furnace opening resistance calculation method of the converter exhaust gas treatment unit and calculates the resistance.

The other main present invention for solving the above-mentioned problems is a control device for controlling the furnace pressure, which is the differential pressure between the furnace internal pressure and the atmospheric pressure, in the converter exhaust gas treatment apparatus for collecting the exhaust gas generated in the converter in the gas holder. The concentration data obtained by measuring the concentration of the gas contained in the exhaust gas and the exhaust gas flow rate are measured from the measurement time of the concentration data for a first time corresponding to the measurement time difference between the gas concentration and the exhaust gas flow rate. The flow rate data measured before, and the furnace pressure, the furnace pressure data measured before the measurement time of the concentration data for a second time corresponding to the measurement time difference between the gas concentration and the furnace pressure, A furnace port resistance calculating unit that calculates a furnace port resistance between the furnace port and the skirt, a proportional gain setting unit that sets a proportional gain so that the furnace port resistance increases, and the furnace port resistance Is bigger An integration time setting unit that sets an integration time so as to increase, and a PI control unit that outputs a control signal for controlling the furnace pressure to a target value according to the proportional gain and the integration time, and When the furnace pressure data indicates the intake of air from the furnace port, the furnace port resistance calculation unit calculates the amount of air sucked from the furnace port based on the flow rate data and the concentration data. The furnace port resistance is calculated based on the furnace pressure data and the amount of air sucked, and if the furnace pressure data does not indicate air suction from the furnace port, the furnace previously calculated mouth resistance, a furnace pressure control device of the converter exhaust gas treatment unit and calculates as the furnace opening resistance.

  Other features of the present invention will become apparent from the accompanying drawings and the description of this specification.

  According to the present invention, the furnace port resistance during operation can be calculated in real time and used for furnace pressure control and the like.

It is a flowchart explaining the calculation method of the furnace port resistance in one Embodiment of this invention. It is a schematic diagram which shows an example of the measurement time difference of each measurement data. It is a figure which shows an example of a structure of a converter exhaust gas processing apparatus. It is a flowchart explaining the calculation method of the suction | inhalation amount Fin of the air from a furnace port, and the discharge amount Fout of exhaust gas. It is a figure explaining the method of integrating | accumulating the suction amount Fin and the blowing amount Fout, and evaluating the controllability of the furnace pressure control system of a converter exhaust gas processing apparatus. It is a block diagram which shows the structure of the furnace pressure control apparatus of the converter exhaust gas processing apparatus in one Embodiment of this invention.

  At least the following matters will become apparent from the description of this specification and the accompanying drawings.

=== Configuration and Operation of Converter Exhaust Gas Treatment Apparatus ===
Hereinafter, the configuration and operation of the converter exhaust gas treatment apparatus will be described with reference to FIG.

  The converter exhaust gas treatment apparatus shown in FIG. 3 is an apparatus for collecting the exhaust gas generated in the converter 1 in the gas holder 10, and in addition, the skirt 2, the boiler 3, the gas cooling washer 4, the IDF. (Induced Draft Fan: induction fan) 5, three-way valve 6, bypass valve 7, gas diffusion tower 8, recovery valve 9, and damper 11 are included.

  The exhaust gas generated in the converter 1 is collected by a skirt 2 that covers the top of the converter 1. At this time, when the skirt 2 is lowered, the combustion of carbon monoxide at the furnace port is eliminated, and the concentration of carbon monoxide contained in the exhaust gas is increased. Further, since the exhaust gas collected by the skirt 2 has a high amount of dust at a high temperature, the temperature is removed by the boiler 3 and the gas cooling washer 4.

  The exhaust gas from which the temperature has been removed is blown by the IDF 5 and reaches the three-way valve 6. At that time, the exhaust gas flow rate is controlled by adjusting the opening degree of the damper 11, and as a result, the furnace pressure is controlled. The three-way valve 6 switches the flow path of the exhaust gas to the gas holder 10 side or the gas diffusion tower 8 side. When the three-way valve 6 is on the gas holder 10 side, the exhaust gas reaches the gas holder 10 via the recovery valve 9 and is recovered. On the other hand, when the three-way valve 6 is on the gas diffusion tower 8 side, the exhaust gas reaches the gas diffusion tower 8, burns carbon monoxide, and is then diffused into the atmosphere. The converter exhaust gas treatment apparatus is also provided with a bypass valve 7 that guides the exhaust gas to the gas diffusion tower 8 in preparation for a failure of the three-way valve 6.

  In this way, the exhaust gas generated in the converter 1 is collected in the gas holder 10 according to the state of the three-way valve 6 or is diffused from the gas diffusion tower 8 to the atmosphere. The exhaust gas stored in the gas holder 10 is mixed with other by-product gas and then used in a heating furnace or a power generation system.

Furthermore, various sensors are attached to the converter exhaust gas treatment apparatus. For example, a furnace pressure gauge 21 for measuring the furnace pressure P0 is disposed in the duct above the skirt 2. Further, in the boiler 3 which is a path of the exhaust gas before the temperature reduction and dust removal, a CO analyzer 22 for measuring the concentration of carbon monoxide (hereinafter referred to as CO concentration) R1 contained in the exhaust gas, and the concentration of carbon dioxide (hereinafter referred to as CO concentration). A CO ₂ analyzer 23 for measuring R2 (referred to as CO ₂ concentration). On the other hand, in the path of the exhaust gas after the temperature reduction and dust removal by the boiler 3 and the gas cooling washer 4, a flow meter 24 for measuring the exhaust gas flow rate F1 and an O ₂ analysis for measuring the concentration of oxygen (O ₂ ) contained in the exhaust gas. A total of 25 is arranged.

In addition, the measurement data by each sensor changes according to the opening degree of the damper 11. FIG. By adjusting the opening degree of the damper 11, the exhaust gas flow rate F1 and the furnace pressure P0 are controlled, and as a result, the gas concentration measured by each analyzer (22, 23, 25) also changes. When nitrogen is blown into the furnace from the bottom of the converter 1, the nitrogen blowing amount (hereinafter referred to as N ₂ blowing amount) F < _b > 2 is used in calculating the furnace port resistance.

=== Calculation method of furnace opening resistance ===
Hereinafter, with reference to FIG. 1 and FIG. 2, the calculation method of the furnace port resistance in one Embodiment of this invention is demonstrated.

There is a measurement time difference between the measurement data of each sensor depending on the position of each sensor and the time required for gas analysis in each analyzer. For example, when the amount of exhaust gas generated or the concentration of gas contained in the exhaust gas changes at a certain time, the furnace pressure P0, which is the difference between the furnace pressure and the atmospheric pressure, and the amount of nitrogen blown into the furnace F2 are: The change is reflected with almost no time difference. On the other hand, in the exhaust gas flow rate F1 measured in the flow path between the gas cooling washer 4 and the IDF 5, the change is reflected with a delay corresponding to the movement time Ta of the exhaust gas. Further, the CO concentration R1 and CO ₂ concentration R2, so that the amount corresponding change in the analysis time Tb (> Ta) of each analyzer is reflected with a delay.

Therefore, as shown in FIG. 2, for the CO concentration R1 (t) and the CO ₂ concentration R2 (t) measured at time t, the exhaust gas flow rate F1 (t-t1) measured at time t-t1, and It is necessary to use the furnace pressure P0 (t-t2) measured at time t-t2 and the N ₂ injection amount F2 (t-t2) in association with each other. Here, the first time t1 is the CO concentration R1, CO ₂ concentration R2, corresponds to the measured time difference between the exhaust gas flow rate F1, is t1 = Tb-Ta. On the other hand, the second time t2 is the CO concentration R1, CO ₂ concentration R2, corresponds to the measured time difference between the furnace pressure P0, which is t2 = Tb.

As shown in FIG. 1, in calculating the furnace port resistance k (t) at time t, first, the CO concentration R1 (t), the CO ₂ concentration R2 (t), the exhaust gas flow rate F1 (t-t1), the furnace pressure P0 (t−t2) is acquired (S11). Incidentally, CO concentration R1 (t), CO ₂ concentration R2 (t) corresponds to the density data, the exhaust gas flow rate F1 (t-t1) corresponds to the flow rate data, furnace pressure P0 (t-t2) is furnace pressure data It corresponds to.

と算出される。 Next, when the furnace pressure P0 (t−t2) <0 and the intake of air from the furnace port is indicated (S12: YES), the exhaust gas flow rate F1 (t−t1), the CO concentration R1 (t ), A flow rate of nitrogen (hereinafter referred to as N ₂ flow rate) F3 (t) contained in the exhaust gas is calculated based on the CO ₂ concentration R2 (t) (S13). Here, assuming that the gas contained in the exhaust gas is substantially only nitrogen, carbon monoxide, and carbon dioxide, the N ₂ flow rate F3 (t) is

Is calculated.

と算出される。ここで、Ｒ０は、空気中の窒素の濃度であり、約７８％である。一方、転炉１の底部から炉内に窒素が吹き込まれていない場合（Ｓ１４：ＮＯ）には、

と算出される（Ｓ１７）。 Next, when nitrogen is blown into the furnace from the bottom of the converter 1 (S14: YES), an N ₂ blowing amount F2 (t−t2) is acquired (S15), and an N ₂ flow rate F3 (t ) And the N ₂ blowing amount F2 (t−t2), the air suction amount Fin (t) from the furnace port is calculated (S16). The N ₂ blowing amount F2 (t−t2) corresponds to the blowing amount data. The suction amount Fin (t) is

Is calculated. Here, R0 is the concentration of nitrogen in the air and is about 78%. On the other hand, when nitrogen is not blown into the furnace from the bottom of the converter 1 (S14: NO),

Is calculated (S17).

と算出される。ここで、炉圧Ｐ０（ｔ−ｔ２）＜０であるため、炉口抵抗ｋ（ｔ）＞０である。式（２），（３），（５）より、転炉１の底部から炉内に窒素が吹き込まれている場合（Ｓ１４：ＹＥＳ）には、

となる。一方、式（２），（４），（５）より、転炉１の底部から炉内に窒素が吹き込まれていない場合（Ｓ１４：ＮＯ）には、

となる。 Finally, the furnace port resistance k (t) is calculated based on the furnace pressure P0 (t−t2) and the suction amount Fin (t) (S18). The furnace resistance k (t) is

Is calculated. Here, since furnace pressure P0 (t−t2) <0, furnace opening resistance k (t)> 0. From the formulas (2), (3), and (5), when nitrogen is blown into the furnace from the bottom of the converter 1 (S14: YES),

It becomes. On the other hand, from the formulas (2), (4), and (5), when nitrogen is not blown into the furnace from the bottom of the converter 1 (S14: NO),

It becomes.

と算出すればよい（Ｓ１９）。 On the other hand, when the furnace pressure P0 (t−t2) ≧ 0 and no suction of air from the furnace port is indicated (S12: NO), since exhaust gas is blown out from the furnace port, the equation (6), The furnace port resistance k (t) cannot be calculated from (7). Therefore, in this case, the furnace port resistance calculated last from the equations (6) and (7) is calculated as the furnace port resistance k (t). Here, assuming that the furnace port resistance k (t) is calculated for each predetermined measurement cycle Δt, the furnace port resistance k (t) in this case is the furnace port resistance k (t−Δt) in the previous measurement cycle. )Using,

(S19).

  In this way, whether the air is sucked from the furnace port (P0 <0) or the exhaust gas blows out from the furnace port (P0 ≧ 0), the furnace port resistance during operation can be calculated in real time.

  In the present embodiment, when exhaust gas is blown out from the furnace port, the furnace port resistance calculated last in a state where air is sucked from the furnace port is calculated as the furnace port resistance k (t). However, it is not limited to this. The furnace port resistance k (t) when exhaust gas is blown out from the furnace port may be calculated by other methods based on the furnace port resistance calculated in the past. For example, the furnace port resistance in each measurement cycle is stored in the storage means for a predetermined period, and when exhaust gas is blown out from the furnace port, the moving average value for the predetermined period is set as the furnace port resistance k (t). It may be calculated. At this time, the storage means may always store the furnace port resistance in each measurement cycle, or may store only the furnace port resistance calculated in a state where air is sucked from the furnace port.

=== Method for evaluating the controllability of the furnace pressure control system ===
Hereinafter, a method for evaluating the controllability of the furnace pressure control system of the converter exhaust gas treatment apparatus using the calculated furnace port resistance will be described with reference to FIGS. 4 and 5.

  As shown in Fig. 1, by calculating the furnace port resistance during operation in real time, not only the amount of air sucked in from the furnace port, which was conventionally possible, but also the amount of exhaust gas discharged from the furnace port is calculated. can do.

  As shown in FIG. 4, when the furnace pressure P0 (t−t2) <0 and air suction from the furnace port is indicated (S21: YES), the suction is performed from the equations (3) and (4). The amount Fin (t) can be calculated and used (S22).

と算出することができる。 On the other hand, when the furnace pressure P0 (t−t2) ≧ 0 and air suction from the furnace port is not indicated (S21: NO), the furnace port resistance k (t) and the furnace pressure P0 (t−t2) ) To calculate the amount Fout (t) of exhaust gas discharged from the furnace port (S23). The blowout amount Fout (t) is

Can be calculated.

  Then, the suction amount Fin and the blowout amount Fout calculated in this way can be integrated and used as a controllability evaluation index of the furnace pressure control system of the converter exhaust gas treatment apparatus. As shown in FIG. 5, first, each integrated value is reset at the start of operation, and then the integration is started at the start of exhaust gas recovery, and the integration is stopped at the end of recovery. At this time, the suction amount Fin is integrated while air is sucked from the furnace port (P0 <0), and the blowout amount Fout is integrated while exhaust gas is blown from the furnace port (P0 ≧ 0).

  As described above, the amount of carbon monoxide contained in the exhaust gas is reduced both when air is sucked from the furnace port and when exhaust gas blows out from the furnace port. Therefore, it can be evaluated that the exhaust gas containing carbon monoxide at a high concentration is more efficiently recovered as the integrated value of the suction amount Fin and the blowout amount Fout is smaller.

  In this way, by calculating not only the amount of air sucked from the furnace port, but also the amount of exhaust gas discharged from the furnace port using the furnace port resistance, those integrated values are used as evaluation indexes for the converter exhaust gas treatment device. The controllability of the furnace pressure control system can be evaluated. Thereby, for example, a plurality of operations in one day can be compared, or operations in the same time zone on a plurality of operation days can be compared.

=== Configuration of Furnace Pressure Control Device ===
Hereinafter, with reference to FIG. 6, the structure of the furnace pressure control apparatus of the converter exhaust gas processing apparatus in one Embodiment of this invention is demonstrated.

  The furnace pressure control device 30 shown in FIG. 6 includes a furnace port resistance calculation unit 301, a proportional gain setting unit 302, an integration time setting unit 303, a PI control unit 304, and a communication unit, which are connected to each other via a bus 309. 305, an input unit 306, an output unit 307, and a storage unit 308 are configured. The function of the furnace pressure control device 30 can be realized by a computer 300 including a communication unit 305, an input unit 306, an output unit 307, a storage unit 308, and a bus 309.

The communication unit 305 can communicate with the sensors and the damper 11 of the converter exhaust gas treatment device. The communication unit 305 receives the furnace pressure P0 from the furnace pressure meter 21, the CO concentration R1 from the CO analyzer 22, the CO ₂ concentration R2 from the CO ₂ analyzer 23, the exhaust gas flow rate F1 from the flow meter 24, and the N from the converter 1. Each of the _two blowing amounts F2 is received. Each received measurement data is stored in the storage unit 308 as time series data.

The furnace opening resistance calculating section 301, the furnace pressure P0 (t-t2), CO concentration R1 (t), CO ₂ concentration R2 (t), exhaust gas flow rate _{F1 (t-t1), N} 2 blow amount F2 (t- t2) is input. Further, the furnace port resistance k (t) output from the furnace port resistance calculation unit 301 is input to the proportional gain setting unit 302 and the integration time setting unit 303. Further, the proportional gain Kp output from the proportional gain setting unit 302 and the integration time Ti output from the integration time setting unit 303 are input to the PI control unit 304. The control signal MV output from the PI control unit 304 is transmitted from the communication unit 305 to the damper 11.

=== Operation of the furnace pressure control apparatus ===
Hereinafter, the operation of the furnace pressure control device of the converter exhaust gas treatment device in the present embodiment will be described.

  Control of the converter exhaust gas treatment device by the furnace pressure control device 30 includes furnace port resistance calculation processing by the furnace port resistance calculation unit 301, proportional gain setting processing by the proportional gain setting unit 302, integration time setting processing by the integration time setting unit 303, And a control signal output process by the PI control unit 304. As described above, the function of the furnace pressure control device 30 can be realized by the computer 300. For example, by causing the computer 300 to execute a furnace pressure control program, it is possible to execute furnace port resistance calculation processing, proportional gain setting processing, integration time setting processing, and control signal output processing.

  In the furnace port resistance calculation process, the furnace port resistance k (t) during operation is calculated in real time as shown in FIG. In the proportional gain setting process and the integration time setting process, the proportional gain Kp and the integration time Ti are set using the calculated furnace port resistance k (t), respectively.

  Here, if the furnace port resistance k is small, even if the furnace pressure P0 is small, the air suction amount Fin and the exhaust gas blowing amount Fout from the furnace port increase. That is, when the furnace port resistance k is small, the gain in the furnace pressure control of the plant is small, and it is necessary to operate many operation ends. Therefore, it is necessary to increase the proportional gain Kp of the PI control unit 304 and reduce the integration time Ti. On the other hand, when the furnace port resistance k is large, the gain in the furnace pressure control of the plant becomes large, and it is necessary to operate the operation end with a small amount. Therefore, it is necessary to reduce the proportional gain Kp of the PI control unit 304 and increase the integration time Ti.

  Therefore, in the proportional gain setting process, the proportional gain Kp is set to be smaller as the furnace port resistance k is larger, and in the integration time setting process, the integration time Ti is set to be larger as the furnace port resistance k is larger. In the control signal output process, the control signal MV for controlling the furnace pressure P0 to the target value is output in accordance with the set proportional gain Kp and the integration time Ti, and the opening of the damper 11 is adjusted, so that the exhaust gas is discharged. The flow rate F1 and the furnace pressure P0 are controlled.

  Thus, the furnace pressure can be controlled more efficiently by setting the control parameter for PI control using the furnace opening resistance.

As described above, in the method of calculating the furnace port resistance in the converter exhaust gas treatment apparatus, when the furnace pressure P0 (t−t2) <0, the exhaust gas flow rate F1 (t−t1), the CO concentration R1 (t), The suction amount Fin (t) is calculated based on the CO ₂ concentration R2 (t), and the furnace port resistance k (t) is calculated based on the furnace pressure P0 (t-t2) and the suction amount Fin (t). When the pressure P0 (t−t2) ≧ 0, it is possible to calculate the furnace port resistance k (t) based on the furnace port resistance calculated in the past. Even when exhaust gas blows out from the furnace, the resistance of the furnace port during operation is calculated in real time and used for furnace pressure control and the like.

Further, by calculating the N ₂ flow rate F3 (t) based on the exhaust gas flow rate F1 (t−t1), the CO concentration R1 (t), and the CO ₂ concentration R2 (t), the N ₂ flow rate F3 (t), air The suction amount Fin (t) can be calculated based on the nitrogen concentration R0 in the inside.

Moreover, when nitrogen is blown into the furnace from the bottom of the converter 1, the difference between the N ₂ flow rate F3 (t) and the N ₂ blowing amount F2 (t−t2) and the nitrogen concentration R0 in the air based on the bets, by calculating the _{N 2} flow rate F3 (t), _{N 2} flow rate F3 (t), based on the nitrogen concentration R0 in the air, it is possible to calculate the intake amount Fin (t).

  Further, not only the air suction amount Fin (t) from the furnace port but also the furnace port resistance k (t) and the furnace pressure P0 (t-t2) when the furnace pressure P0 (t−t2) ≧ 0. Then, the controllability of the furnace pressure control system of the converter exhaust gas treatment apparatus is calculated using the integrated value of the calculated suction amount Fin and the blowout amount Fout as an evaluation index by calculating the blowout amount Fout (t) of the exhaust gas from the furnace port. Can be evaluated.

  Further, as described above, in the furnace pressure control device 30 for controlling the furnace pressure of the converter exhaust gas treatment device, the proportional gain Kp is set to be smaller and the integration time Ti is set to be larger as the furnace port resistance k is larger. Thus, whether the air is sucked from the furnace port or the exhaust gas is blown out from the furnace port, the furnace port resistance during operation can be calculated in real time to control the furnace pressure more efficiently.

  Further, in a program for causing a computer to execute processing corresponding to the furnace port resistance calculation unit 301, the proportional gain setting unit 302, the integration time setting unit 303, and the PI control unit 304 of the furnace pressure control device 30, By setting so that the proportional gain Kp decreases and the integration time Ti increases as k increases, the furnace port resistance during operation can be calculated in real time, and the furnace pressure can be controlled more efficiently.

  Also, by setting the proportional gain Kp to be smaller and the integration time Ti to be larger as the furnace port resistance k is larger, the furnace port resistance during operation is calculated in real time and the furnace pressure is controlled more efficiently. can do.

  In addition, the said embodiment is for making an understanding of this invention easy, and is not for limiting and interpreting this invention. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes equivalents thereof.

1 Converter 2 Skirt 3 Boiler 4 Gas-cooled washing machine 5 IDF (attraction fan)
6 Three-way valve 7 Bypass valve 8 Gas diffusion tower 9 Recovery valve 10 Gas holder 11 Damper 21 Furnace pressure gauge 22 CO (carbon monoxide) analyzer 23 CO ₂ (carbon dioxide) analyzer 24 Flow meter 25 O ₂ (oxygen) analyzer 30 Furnace pressure control device 300 Computer 301 Furnace port resistance calculation unit 302 Proportional gain setting unit 303 Integration time setting unit 304 PI (proportional / integration) control unit 305 Communication unit 306 Input unit 307 Output unit 308 Storage unit 309 Bus

Claims (7)

A method of calculating a furnace port resistance between a furnace port and a skirt in a converter exhaust gas treatment apparatus that collects exhaust gas generated in a converter in a gas holder,
Concentration data obtained by measuring the concentration of gas contained in the exhaust gas and the exhaust gas flow rate were measured prior to the measurement time of the concentration data for a first time corresponding to the measurement time difference between the gas concentration and the exhaust gas flow rate. The flow rate data and the furnace pressure, which is the differential pressure between the furnace pressure and the atmospheric pressure, were measured prior to the concentration data measurement time for a second time corresponding to the measurement time difference between the gas concentration and the furnace pressure. Furnace pressure data,
If the furnace pressure data indicates air inhalation from the furnace port,
Based on the flow rate data and the concentration data, calculate the amount of air sucked from the furnace port,
Based on the furnace pressure data and the air suction amount, calculate the furnace port resistance,
If the furnace pressure data does not indicate air inhalation from the furnace port,
The calculated throat resistance in the past, throat resistance calculation method of the converter exhaust gas treatment unit and calculates as the furnace opening resistance. A furnace port resistance calculation method for a converter exhaust gas treatment apparatus according to claim 1,
If the furnace pressure data indicates air inhalation from the furnace port,
Based on the flow rate data and the concentration data, the flow rate of nitrogen contained in the exhaust gas is calculated,
Based on the flow rate of nitrogen and the concentration of nitrogen in the air, the amount of air suction is calculated,
A furnace port resistance calculation method for a converter exhaust gas treatment apparatus, wherein the furnace port resistance is calculated based on the furnace pressure data and the air suction amount. A furnace port resistance calculation method for a converter exhaust gas treatment device according to claim 2,
When the furnace pressure data indicates the suction of air from the furnace port, when nitrogen is blown from the bottom of the converter,
Further acquiring the amount of nitrogen blown from the bottom of the converter, the amount of blown gas measured before the measurement time of the concentration data for the second time,
Based on the flow rate data and the concentration data, the flow rate of nitrogen contained in the exhaust gas is calculated,
Based on the difference between the flow rate of the nitrogen and the blowing amount data and the concentration of nitrogen in the air, the amount of air sucked is calculated,
A furnace port resistance calculation method for a converter exhaust gas treatment apparatus, wherein the furnace port resistance is calculated based on the furnace pressure data and the air suction amount. If the furnace pressure data does not indicate air inhalation from the furnace port,
The exhaust gas from the furnace port is calculated based on the furnace port resistance calculated by the furnace port resistance calculation method of the converter exhaust gas treatment apparatus according to any one of claims 1 to 3 and the furnace pressure data. An exhaust gas amount calculation method for a converter exhaust gas treatment apparatus, characterized in that the air amount is calculated. A control device for controlling a furnace pressure which is a differential pressure between a furnace internal pressure and an atmospheric pressure in a converter exhaust gas treatment apparatus that collects exhaust gas generated in a converter in a gas holder,
Concentration data obtained by measuring the concentration of gas contained in the exhaust gas and the exhaust gas flow rate were measured prior to the measurement time of the concentration data for a first time corresponding to the measurement time difference between the gas concentration and the exhaust gas flow rate. Based on the flow rate data and the furnace pressure, the furnace pressure data measured before the measurement time of the concentration data for a second time corresponding to the difference in measurement time between the gas concentration and the furnace pressure, A furnace port resistance calculation unit for calculating the furnace port resistance between the mouth and the skirt;
A proportional gain setting unit that sets the proportional gain so that the furnace port resistance is increased,
An integration time setting unit for setting the integration time so as to increase as the furnace port resistance increases;
A PI control unit that outputs a control signal for controlling the furnace pressure to a target value according to the proportional gain and the integration time;
Have
The furnace port resistance calculation unit
If the furnace pressure data indicates air inhalation from the furnace port,
Based on the flow rate data and the concentration data, calculate the amount of air sucked from the furnace port,
Based on the furnace pressure data and the air suction amount, calculate the furnace port resistance,
If the furnace pressure data does not indicate air inhalation from the furnace port,
The calculated throat resistance in the past, the furnace pressure control device of the converter exhaust gas treatment unit and calculates as the furnace opening resistance. A control program for controlling a furnace pressure, which is a differential pressure between an internal pressure and an atmospheric pressure in a converter exhaust gas treatment apparatus that collects exhaust gas generated in a converter in a gas holder,
On the computer,
Concentration data obtained by measuring the concentration of gas contained in the exhaust gas and the exhaust gas flow rate were measured prior to the measurement time of the concentration data for a first time corresponding to the measurement time difference between the gas concentration and the exhaust gas flow rate. Based on the flow rate data and the furnace pressure, the furnace pressure data measured before the measurement time of the concentration data for a second time corresponding to the difference in measurement time between the gas concentration and the furnace pressure, Furnace port resistance calculation processing for calculating the furnace port resistance between the mouth and the skirt;
A proportional gain setting process for setting a proportional gain so as to decrease as the furnace port resistance increases;
An integration time setting process for setting the integration time so as to increase as the furnace opening resistance increases;
Control signal output processing for outputting a control signal for controlling the furnace pressure to a target value according to the proportional gain and the integration time;
And execute
The furnace port resistance calculation process is:
If the furnace pressure data indicates air inhalation from the furnace port,
Based on the flow rate data and the concentration data, calculate the amount of air sucked from the furnace port,
Based on the furnace pressure data and the air suction amount, calculate the furnace port resistance,
If the furnace pressure data does not indicate air inhalation from the furnace port,
A furnace pressure control program for a converter exhaust gas treatment apparatus, wherein the furnace port resistance is calculated based on a furnace port resistance calculated in the past. A method for controlling a furnace pressure, which is a differential pressure between a furnace internal pressure and an atmospheric pressure in a converter exhaust gas treatment apparatus that collects exhaust gas generated in a converter in a gas holder,
Concentration data obtained by measuring the concentration of gas contained in the exhaust gas and the exhaust gas flow rate were measured prior to the measurement time of the concentration data for a first time corresponding to the measurement time difference between the gas concentration and the exhaust gas flow rate. Flow rate data, and furnace pressure data obtained by measuring the furnace pressure before the measurement time of the concentration data for a second time corresponding to the measurement time difference between the gas concentration and the furnace pressure,
If the furnace pressure data indicates air inhalation from the furnace port,
Based on the flow rate data and the concentration data, calculate the amount of air sucked from the furnace port,
Based on the furnace pressure data and the air suction amount, calculate the furnace port resistance between the furnace port and the skirt,
If the furnace pressure data does not indicate air inhalation from the furnace port,
Based on the furnace port resistance calculated in the past, calculate the furnace port resistance,
Set the proportional gain so that the furnace opening resistance is smaller,
Set the integration time so that the larger the furnace opening resistance,
A furnace pressure control method for a converter exhaust gas treatment apparatus, wherein a control signal for controlling the furnace pressure to a target value is output according to the proportional gain and the integration time.

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