JP6299675B2 - Converter gas recovery device and converter gas recovery method - Google Patents

Description

  The present invention relates to a converter gas recovery device and a converter gas recovery method for recovering converter gas generated from a converter.

  Conventionally, by-product gases such as blast furnace gas and converter gas generated when iron and steel (same as pig iron and steel) are manufactured in steelworks, heating of coke ovens and steel materials installed in the same steelworks are used. It is used as a heating fuel (ie, combustion gas) when rolling. In such a steelworks, a by-product gas holder that stocks a predetermined amount for each by-product gas is installed in order to cope with a case where the amount of by-product gas generated and the amount of by-product gas used are not synchronized. For example, the by-product gas holder includes a converter gas holder that collects and stores converter gas generated in the blowing process of the converter.

  Generally, a converter gas holder includes a piston that can be raised and lowered according to the amount of stored converter gas inside the holder body, and a converter is provided in a gas storage space formed inside the holder body as the piston moves up and down. Store gas. In such a converter gas holder, the height of the piston with respect to a reference surface such as a floor surface (hereinafter referred to as a holder level) is determined in accordance with the amount of stored converter gas. For example, when the converter gas generated in the process of blowing is recovered from the converter into the converter gas holder, and as a result, the amount of stored converter gas in the converter gas holder increases, the holder level is accordingly increased. Increase (rise). On the other hand, the converter gas discharged from the converter gas holder is supplied to equipment in the steelworks (hereinafter referred to as converter gas combustion equipment) that uses the converter gas as the combustion gas as described above. When the amount of converter gas stored in the furnace gas holder decreases, the holder level decreases (decreases) accordingly.

  Temporarily, the amount of converter gas generated, that is, the amount of converter gas recovered by the converter gas holder, is reduced in the converter gas holder due to unexpectedly overlapping blowing in the same period between the converters in the steel works. When the amount of the converter gas is excessively increased compared to the supply amount of the converter gas supplied to the converter gas combustion facility, the holder level increases to exceed the upper limit value of the facility constraint of the converter gas holder. In this case, the converter gas holder cannot store the converter gas, and is finally forced to diffuse the converter gas into the atmosphere. As a result, the converter gas recovery efficiency deteriorates.

  In addition, the amount of converter gas recovered by the converter gas holder is changed to the amount of converter gas supplied from the converter gas holder to the converter gas combustion facility due to an unexpected delay in the blowing of the converter. In contrast, when the amount is excessively reduced, the holder level is reduced to be below the lower limit value of the equipment restriction of the converter gas holder. In this case, in the converter gas holder, there is a danger of stopping the equipment because the piston inside the converter gas holder excessively descends and reaches the floor.

  Therefore, in order to collect converter gas efficiently and stably, it is extremely important to control the holder level within the upper and lower limits of the equipment restrictions of the converter gas holder. As a conventional technique related to such holder level control, for example, a gas fluctuation amount due to a misprediction is estimated from a past dispersion measurement value within a gas generation time constant, and the estimated gas fluctuation amount is converted into a converter in a converter gas holder. There is a control method for predicting the influence on the gas storage amount and correcting and controlling the holder level so that it falls within the upper and lower limits of the converter gas holder while evaluating the holder level based on this prediction (see Patent Document 1). ).

JP-A 63-26492

  However, with the above-described conventional technology, it is difficult to predict with high accuracy the blowing operation timing of the converter, which often varies greatly due to the influence of troubles in the steelworks. For this reason, the predicted value of the recovery amount of the converter gas recovered in the converter gas holder is greatly deviated from the actual recovery amount, and thus the holder level may not be properly controlled. is there. As a result, the converter gas recovery amount as described above is excessive or low, and it becomes difficult to recover the converter gas efficiently and stably.

  The present invention has been made in view of the above circumstances, and ensures a stable operation of converter gas recovery and converter gas recovery device and converter gas capable of recovering converter gas efficiently. The purpose is to provide a collection method.

  In order to solve the above-described problems and achieve the object, a converter gas recovery apparatus according to the present invention recovers and stores a converter gas generated by blowing a converter, and the converter A level meter that measures a holder level that increases or decreases according to the amount of converter gas stored in the gas holder, a converter gas blower that supplies the converter gas from the converter gas holder to a converter gas combustion facility, and the converter The scheduled value of the holder level scheduled for the converter gas holder is set between the upper limit value and the lower limit value of the holder level based on the blowing schedule of the converter and the operation schedule of the converter gas combustion facility The actual level of the start of the blowing of the converter is calculated based on the holder level setting unit to be operated and the operation results before and after the start of the blowing of the converter. Said converter And a prediction processing unit for predicting the gas recovery execution period of the gas, and in the gas recovery execution period, the measured value of the holder level by the level meter is larger than the expected value of the holder level, and the holder level When the amount of time change of the measured value is larger than the amount of time change of the expected value of the holder level, the output of the converter gas blower is controlled so as to increase the supply amount of the converter gas to the converter gas combustion facility. In the non-recovery period other than the gas recovery execution period, the measured value of the holder level is smaller than the scheduled value of the holder level, and the time change amount of the measured value of the holder level is the holder level. Is smaller than the amount of time change of the scheduled value, the output of the converter gas blower is controlled so as to reduce the supply amount of the converter gas to the converter gas combustion facility. Characterized by comprising a control unit.

  Further, in the converter gas recovery apparatus according to the present invention, in the above invention, when the measured value of the holder level reaches a lower limit value of the holder level during the non-recovery period, the control unit Of the converter gas blower so as to stop the supply of the converter gas to the converter gas combustion facility during a period from when the measured value of the holder level reaches the lower limit value of the holder level to the start time of the gas recovery execution period. It is characterized by controlling the output.

  Further, the converter gas recovery apparatus according to the present invention is the converter gas combustion apparatus according to the above invention, wherein the control unit performs the converter gas combustion when the start time of the gas recovery execution period is earlier than the blowing operation schedule. Increasing the supply amount of the converter gas to the facility so that the measured value of the holder level at the start time of the gas recovery execution period is less than the planned value of the holder level and equal to or greater than the lower limit value of the holder level. The output of the converter gas blower is controlled.

  Further, the converter gas recovery method according to the present invention recovers and stores the converter gas generated by blowing the converter in the converter gas holder, and converts the converter gas combustion equipment from the converter gas holder by the converter gas blower. In the converter gas recovery method of supplying the converter gas to the converter, the amount of storage of the converter gas in the converter gas holder based on the blowing operation schedule of the converter and the operation schedule of the converter gas combustion facility A setting process step for setting a predetermined value of the holder level that is planned for the converter gas holder as a holder level that increases or decreases in accordance with the value between an upper limit value and a lower limit value of the holder level, and blowing of the converter Based on the operation results before and after the start, the actual blowing start time of the converter is calculated, and the gas recovery execution period of the converter gas generated by the blowing started at the actual blowing start time is predicted. In the prediction processing step, and in the gas recovery execution period, the measured value of the holder level by the level meter is larger than the expected value of the holder level, and the time change amount of the measured value of the holder level is the holder. If the level is larger than the amount of change over time, the output of the converter gas blower is controlled so as to increase the supply amount of the converter gas to the converter gas combustion facility, and it is outside the gas recovery execution period. In a certain non-recovery period, the measured value of the holder level is smaller than the planned value of the holder level, and the time change amount of the measured value of the holder level is compared to the time change amount of the planned value of the holder level. A control step of controlling an output of the converter gas blower so as to reduce a supply amount of the converter gas to the converter gas combustion facility. The features.

  The converter gas recovery method according to the present invention is the converter gas recovery method according to the above invention, wherein, in the non-recovery period, the control step is performed when the measured value of the holder level reaches a lower limit value of the holder level. Of the converter gas blower so as to stop the supply of the converter gas to the converter gas combustion facility during a period from when the measured value of the holder level reaches the lower limit value of the holder level to the start time of the gas recovery execution period. It is characterized by controlling the output.

  Further, the converter gas recovery method according to the present invention is the converter gas combustion method according to the above invention, wherein the control step is performed when the start time of the gas recovery execution period is earlier than the blowing operation schedule. Increasing the supply amount of the converter gas to the facility so that the measured value of the holder level at the start time of the gas recovery execution period is less than the planned value of the holder level and equal to or greater than the lower limit value of the holder level. The output of the converter gas blower is controlled.

  ADVANTAGE OF THE INVENTION According to this invention, while ensuring the stable operation of converter gas collection | recovery, there exists an effect that converter gas can be collect | recovered efficiently.

FIG. 1 is a diagram illustrating a configuration example of a converter gas recovery apparatus according to an embodiment of the present invention. FIG. 2 is a diagram showing an example of a converter blowing operation schedule in the embodiment of the present invention. FIG. 3 is a diagram illustrating an example of a blowing operation schedule that is unexpectedly changed due to a trouble or the like during actual operation of each converter. FIG. 4 is a flowchart showing an example of the converter gas recovery method according to the embodiment of the present invention. FIG. 5 is a diagram for specifically explaining each process of the converter gas recovery method according to the embodiment of the present invention.

  Hereinafter, preferred embodiments of a converter gas recovery apparatus and a converter gas recovery method according to the present invention will be described in detail with reference to the accompanying drawings. Note that the present invention is not limited to the embodiment. Moreover, the drawings are schematic, and it should be noted that the relationship between the dimensions of each element, the ratio of each element, and the like may differ from the actual ones. Even between the drawings, there are cases in which portions having different dimensional relationships and ratios are included. Moreover, in each drawing, the same code | symbol is attached | subjected to the same component.

(Converter gas recovery device)
First, the structure of the converter gas recovery apparatus concerning embodiment of this invention is demonstrated. FIG. 1 is a diagram illustrating a configuration example of a converter gas recovery apparatus according to an embodiment of the present invention. As shown in FIG. 1, a converter gas recovery apparatus 1 according to an embodiment of the present invention includes a converter gas holder 2 that recovers and stores converter gas, and a level meter that measures the holder level of the converter gas holder 2. 3, a combustion diffusion tower 4 that dissipates excess converter gas that cannot be recovered in the converter gas holder 2, and a converter gas blower that supplies the converter gas in the converter gas holder 2 to the converter gas combustion facility 30. 5, a gas recovery pipe 6 for converter gas recovery, and a gas supply pipe 7 for converter gas supply. Further, the converter gas recovery apparatus 1 includes an input unit 8 for inputting various information, a computer 9 for performing various processes for controlling the holder level, and output control of the converter gas blower 5 to appropriately control the holder level. The control part 10 which performs is provided.

  The converter gas holder 2 is equipment for collecting and storing converter gas generated by blowing the converter. Specifically, the converter gas holder 2 includes a cylindrical holder body (not shown) and a piston (not shown) that can be raised and lowered according to the amount of the converter gas flowing into the holder body. Prepare. The converter gas holder 2 collects and stores the converter gas in a gas storage space formed inside the holder body as the piston moves up and down. In the present embodiment, the converter gas holder 2 is blown from each of the plurality of converters 20 (for example, the first converter 21, the second converter 22, the third converter 23, and the fourth converter 24). The converter gas 15 is recovered, and the recovered converter gas 15 is stored. The holder level of such a converter gas holder 2 increases (increases) with an increase in the storage amount of the converter gas 15 collected in the converter gas holder 2, and with a decrease in the storage amount of the converter gas 15. Decrease (decrease).

  Here, the above-mentioned holder level is a value indicating the height of the piston with respect to a reference surface such as a floor surface in the converter gas holder 2. Such a holder level includes an upper limit value Lmax and a lower limit value Lmin due to equipment restrictions of the converter gas holder 2. In the situation where the holder level exceeds the upper limit value Lmax, there is a risk that the converter gas holder 2 may be destroyed due to an internal piston colliding with the ceiling of the holder body. Therefore, the converter gas holder 2 cannot collect and store the converter gas 15. Further, in a situation where the holder level is lower than the lower limit Lmin, the converter gas holder 2 may be destroyed due to the installation of a piston inside the converter gas. As a result, the converter gas holder 2 may be stopped. There is.

  The level meter 3 is a facility for measuring a holder level that increases or decreases in accordance with the storage amount of the converter gas 15 in the converter gas holder 2, and is provided in the converter gas holder 2. The level meter 3 continuously measures the holder level of the converter gas holder 2 along the time series, and transmits the measured value of the holder level (hereinafter referred to as the measured holder level as appropriate) to the control unit 10 each time. To do.

The combustion stripping tower 4 is for preventing equipment destruction of the converter gas holder 2 due to excessive recovery (that is, excessive storage amount) of the converter gas 15. Specifically, the combustion-dissipating tower 4 has a gas storage capacity (for example, 70,000 [Nm ³ (normal) of the converter gas holder 2) among the converter gases 15 collected from the converters 20 to the converter gas holder 2. Excess excess over Lube)]) is burned and released. At this time, the combustion stripping tower 4 burns excess converter gas 15 into the atmosphere after burning. Thereby, the combustion stripping tower 4 prevents the situation where the piston in the converter gas holder 2 collides with the ceiling of the holder main body and the equipment of the converter gas holder 2 is destroyed.

  The converter gas blower 5 is a facility for supplying the converter gas 15 from the converter gas holder 2 to the converter gas combustion facility 30. The converter gas blower 5 operates based on the control of the control unit 10 and supplies the converter gas 15 stored in the converter gas holder 2 to the converter gas combustion facility 30. At this time, the supply amount of the converter gas 15 supplied from the converter gas holder 2 to the converter gas combustion facility 30 by the converter gas blower 5 is controlled by the control unit 10.

  The gas recovery pipe 6 is a pipe for recovering the converter gas 15 from the plurality of converters 20 to the converter gas holder 2. In the present embodiment, as shown in FIG. 1, the gas recovery pipe 6 includes the first converter 21, the second converter 22, the third converter 23, the fourth converter 24, and the converter gas holder 2. Communicate with. In this state, the gas recovery pipe 6 supplies the converter gas 15 generated from each of the first converter 21, the second converter 22, the third converter 23, and the fourth converter 24 to the inside of the converter gas holder 2. To distribute. On the other hand, when the on-off valve (not shown) of the combustion stripping tower 4 is opened, the gas recovery pipe 6 communicates the converters 20 and the converter gas holder 2 with the combustion stripping tower 4. In this state, the gas recovery pipe 6 circulates the converter gas 15 from at least one of the plurality of converters 20 and the converter gas holder 2 into the combustion diffusion tower 4.

  The gas supply pipe 7 is a pipe for supplying the converter gas 15 from the converter gas holder 2 to the converter gas combustion facility 30. In the present embodiment, as shown in FIG. 1, the gas supply pipe 7 communicates the converter gas holder 2 with the inlet side of the converter gas blower 5, and the outlet side of the converter gas blower 5 with the converter gas combustion. The facility 30 is communicated. The gas supply pipe 7 distributes the converter gas 15 discharged from the converter gas holder 2 by the suction action of the converter gas blower 5 into the converter gas blower 5. Further, the gas supply pipe 7 circulates the converter gas 15 sent from the converter gas blower 5 by the blowing action of the converter gas blower 5 into the converter gas combustion facility 30.

  The input unit 8 is configured using input devices such as input keys and a mouse. The input unit 8 inputs various types of information to the control unit 10 in response to the operator's operation. For example, the information input to the control unit 10 by the input unit 8 includes instruction information for instructing the start or end of the output control of the converter gas blower 5.

  The computer 9 performs processing such as calculation for controlling the holder level of the converter gas holder 2 for collecting and storing the converter gas 15. In the present embodiment, as shown in FIG. 1, the computer 9 includes a holder level setting unit 9 a that sets a planned holder level during operation of the converter gas holder 2, and a plurality of converter gases 20 to a converter gas 15. And a prediction processing unit 9b for predicting an actual period of collecting the data.

  The holder level setting unit 9a sets a holder level that is planned when the converter gas holder 2 receives and discharges the converter gas 15. Specifically, the holder level setting unit 9a acquires the blowing execution schedule of the plurality of converters 20 from the process computer 25 of the steelmaking factory, and the operation schedule of the converter gas combustion facility 30 (hereinafter referred to as the combustion facility operation schedule). ) Is acquired from the process computer 35 in the steelworks. The holder level setting unit 9a, based on the acquired blowing execution schedule and combustion facility operation schedule, sets the planned value of the holder level planned for the converter gas holder 2 (hereinafter referred to as the planned holder level as appropriate), It is set between the upper limit value Lmax and the lower limit value Lmin of the holder level described above.

  In the present embodiment, the blowing execution schedule is information indicating the execution schedule of each blowing of the first converter 21, the second converter 22, the third converter 23, and the fourth converter 24. Such a blowing execution schedule includes a scheduled blowing start time, a scheduled blowing end time, a scheduled blowing execution period, and the like in each of the plurality of converters 20. On the other hand, the combustion facility operation schedule is information indicating a schedule of operations such as heating performed by the converter gas combustion facility 30 by burning the converter gas 15. Such combustion facility operation schedule includes the supply period and supply of the converter gas 15 to the converter gas combustion facility 30, such as the scheduled combustion period and amount of combustion of the converter gas 15 burned by the converter gas combustion facility 30. Contains information related to quantity.

  The prediction processing unit 9 b predicts an actual period for collecting the converter gas 15 from the plurality of converters 20 in the converter gas holder 2. Specifically, the prediction processing unit 9b acquires converter actual operation information indicating operation results before and after the start of blowing in each of the plurality of converters 20 from the process computer 25 of the steelmaking factory. Based on the operation results before and after the start of the blowing of the converter indicated in the converter actual operation information among the plurality of converters 20, the prediction processing unit 9b Calculate the time, that is, the actual time at which the converter starts blowing. Next, the prediction processing unit 9b performs an actual execution period in which the converter gas 15 generated by the blowing that is started at the calculated actual time of the blowing is collected in the converter gas holder 2, that is, the gas of the converter gas 15 Predict the collection execution period.

  In the present embodiment, the actual converter operation information is the flow rate of the blowing performed most recently from the present time in each of the first converter 21, the second converter 22, the third converter 23, and the fourth converter 24. The operation results before and after the start are shown. Among the operation results before and after the start of such blowing, the operation results before the start of blowing include the time when the lance was inserted into the converter, the time when oxygen supply was started into the converter through the inserted lance, etc. included. In addition, the operation results after the start of blowing, more specifically, the operation results from the start of blowing to the start of converter gas recovery, the fluctuation time of the gas pressure in the gas recovery pipe 6, The fluctuation time of the carbon oxide (CO) concentration is included.

  The control unit 10 controls the output of the converter gas blower 5 so that the holder level falls between the upper limit value Lmax and the lower limit value Lmin of the converter gas holder 2. In the present embodiment, the control unit 10 acquires the actual value of the holder level of the converter gas holder 2 by the level meter 3, that is, the actual measured holder level from the level meter 3. Further, the control unit 10 acquires from the computer 9 the scheduled holder level of the converter gas holder 2 set by the holder level setting unit 9a and the gas recovery execution period of the converter gas 15 predicted by the prediction processing unit 9b. . Further, the control unit 10 acquires drive information indicating the current output performance of the converter gas blower 5 from the converter gas blower 5. Based on whether the current time is the gas recovery execution period or the non-recovery period of the converter gas 15 and the magnitude relationship between the planned holder level of the converter gas holder 2 and the actually measured holder level, the control unit 10 The output of the converter gas blower 5 is controlled.

  Specifically, the control unit 10 determines whether or not the present time is the gas recovery execution period of the converter gas 15 based on the obtained prediction result of the gas recovery execution period and the current time. Further, the control unit 10 compares the measured holder level with the planned holder level, and compares the time variation amount of the measured holder level with the time variation amount of the planned holder level.

  When the control unit 10 determines that the current time is the gas recovery execution period of the converter gas 15, the control unit 10 takes into account the gas recovery execution period and adds the result of each comparison process between the measured holder level and the planned holder level described above. Based on this, the output of the converter gas blower 5 is controlled. That is, in the gas recovery execution period, the control unit 10 has a measured holder level larger than the planned holder level, and a time variation amount of the measured holder level is larger than a time variation amount of the planned holder level. The output of the converter gas blower 5 is controlled so as to increase the supply amount of the converter gas 15 to the converter gas combustion facility 30. At this time, the control unit 10 transmits an output command to the converter gas blower 5 so that the output of the converter gas blower 5 becomes larger than the current output performance.

  On the other hand, when the control unit 10 determines that the current period is a period other than the gas recovery execution period of the converter gas 15, that is, the non-recovery period, the above-described measured holder level and planned holder level are taken into account in consideration of this non-recovery period. The output of the converter gas blower 5 is controlled based on the result of each comparison process. That is, in the non-recovery period, the control unit 10 changes the measured holder level when the measured holder level is smaller than the planned holder level and the time change amount of the measured holder level is smaller than the time change amount of the planned holder level. The output of the converter gas blower 5 is controlled so that the supply amount of the converter gas 15 to the furnace gas combustion facility 30 is reduced. At this time, the control unit 10 transmits an output command to the converter gas blower 5 so that the output of the converter gas blower 5 becomes smaller than the current output performance.

  In addition, when the measured holder level reaches the lower limit value Lmin of the holder level in the non-recovery period, the control unit 10 determines the period from the time when the measured holder level reaches the lower limit value Lmin to the start time of the gas recovery execution period. The output of the converter gas blower 5 is controlled so that the supply of the converter gas 15 to the converter gas combustion facility 30 is stopped.

  On the other hand, the control unit 10 increases the supply amount of the converter gas 15 to the converter gas combustion facility 30 when the start time of the gas recovery execution period of the converter gas 15 is earlier than the above-described blowing operation schedule. Thus, the output of the converter gas blower 5 is controlled. At this time, the control unit 10 controls the output of the converter gas blower 5 so that the measured holder level at the start time of the gas recovery execution period is less than the planned holder level and equal to or more than the lower limit Lmin.

  On the other hand, when the measured holder level is equal to or lower than the planned holder level during the gas recovery execution period, the control unit 10 controls the converter gas blower 5 so as to maintain the current supply amount of the converter gas 15 to the converter gas combustion facility 30. Control the output. Further, in the non-recovery period, the control unit 10 outputs the converter gas blower 5 so as to maintain the current supply amount of the converter gas 15 to the converter gas combustion facility 30 when the measured holder level is equal to or higher than the planned holder level. To control.

In the present embodiment, a plurality of converters 20 that generate the converter gas 15 collected in the converter gas holder 2 described above are installed in a steelmaking factory. The plurality of converters 20 include, for example, a first converter 21, a second converter 22, a third converter 23, and a fourth converter 24 as shown in FIG. 1. The first converter 21, the second converter 22, the third converter 23, and the fourth converter 24 each have a predetermined gas flow rate (for example, about 120,000 [Nm ³ ] by blowing one charge. / H], the converter gas 15 is generated batchwise. The process computer 25 is a facility that manages the operation of the plurality of converters 20 and is installed in the steelmaking factory. The process computer 25 provides the computer 9 of the converter gas recovery apparatus 1 with a blow execution schedule and converter actuals of the first converter 21, the second converter 22, the third converter 23, and the fourth converter 24. Send operational information.

  On the other hand, the converter gas combustion facility 30 is a facility in a steel plant that uses the converter gas 15 recovered from the plurality of converters 20 by the converter gas recovery apparatus 1 as a combustion gas. In the present embodiment, as the converter gas combustion facility 30, a heating furnace 31 that heats a steel material to be rolled and a coke oven 32 are exemplified. The process computer 35 is a facility that manages the operation of the converter gas combustion facility 30. The process computer 35 transmits the combustion facility operation schedule of the converter gas combustion facility 30 (the heating furnace 31 and the coke oven 32 in the present embodiment) to the computer 9 of the converter gas recovery apparatus 1.

(Blowing execution schedule)
Below, the blowing operation schedule of the converter in embodiment of this invention is demonstrated. FIG. 2 is a diagram showing an example of a converter blowing operation schedule in the embodiment of the present invention. In FIG. 2, the rectangular mark indicates the scheduled blowing period for each charge.

  In the present embodiment, regular blowing operation is performed in which the first converter 21, the second converter 22, the third converter 23, and the fourth converter 24 are blown at predetermined time intervals at the beginning of operation. A schedule is set. For example, as shown in FIG. 2, in the blowing operation schedule, the first converter 21 has a scheduled blowing operation period set at a predetermined time interval along a time series (time axis of time t). . In the second converter 22, a scheduled blow execution period is set in chronological order at predetermined time intervals so that the blowing is executed between the blowing operations of the first converter 21. In the third converter 23, the scheduled blow execution period is set in chronological order at predetermined time intervals so that the blowing is executed between the blowing operations of the second converter 22. In the fourth converter 24, the scheduled blow execution period is set in chronological order at a predetermined time interval so that the blowing is executed between the blowing operations of the third converter 23.

  In accordance with a regular blowing operation schedule as shown in FIG. 2, each of the first converter 21, the second converter 22, the third converter 23, and the fourth converter 24 (hereinafter referred to as each) When sequentially executed in a converter, the converter gas 15 is generated from each converter at a predetermined time interval. For example, the execution time of one blowing in each converter is about 20 minutes, of which the generation time of the converter gas 15 (that is, the time for which the converter gas 15 is recovered in the converter gas holder 2) is about 15 minutes. In this case, as shown in FIG. 2, blowing is performed in the first converter 21 and the third converter 23 for a period of about 20 minutes from the time ta. Next, the converter gas 15 is generated from the first converter 21 and the third converter 23 for a period of about 15 minutes in this period, and the generated converter gas 15 is collected in the converter gas holder 2. Thereafter, blowing is performed in the second converter 22 and the fourth converter 24 for a period of about 20 minutes from the time tb. Next, the converter gas 15 is generated from the second converter 22 and the fourth converter 24 for a period of about 15 minutes in this period, and the generated converter gas 15 is collected in the converter gas holder 2.

  In this embodiment, the operation of each converter in which blowing is performed at predetermined time intervals in accordance with the regular blowing operation schedule is defined as steady operation in the present embodiment. When the operation of each converter is a steady operation, the converter gas 15 from a plurality of converters 20 (first converter 21, second converter 22, third converter 23, and fourth converter 24) is converted. The amount of generation can be easily predicted based on the blowing operation schedule (see FIG. 2) during this steady operation. Further, the generated amount of the converter gas 15 is generated from a plurality of converters 20 and collected in the converter gas holder 2 unless the converter gas 15 is burned and discharged from the combustion diffusion tower 4 shown in FIG. Equivalent to the recovered amount of converter gas 15.

  In the blowing of each converter, the blowing pattern differs depending on the steel type. For this reason, the execution time of blowing in each converter and the generation time of the converter gas 15 (that is, the recovery time of the converter 15) are different for each steel type. Such information is also reflected in the blowing execution schedule as shown in FIG.

  On the other hand, as shown in FIG. 2, the blowing schedule for regular operation of each converter set regularly is unexpectedly predicted due to troubles in the converter equipment during actual operation of each converter in a steelmaking factory. It will be changed. FIG. 3 is a diagram illustrating an example of a blowing operation schedule that is unexpectedly changed due to a trouble or the like during actual operation of each converter. In FIG. 3, the rectangular mark indicates the scheduled blowing execution period for each charge, as in FIG. 2 described above.

  The regular blowing operation schedule (see FIG. 2) of the first converter 21, the second converter 22, the third converter 23, and the fourth converter 24 is affected by troubles during actual operation of each converter. Due to this, there is a risk of schedule changes such as excessive execution delay or early execution of blowing, or suspension of blowing. For example, in the blowing execution schedule that has been changed unexpectedly due to the influence of a trouble or the like, as shown in FIG. 3, the interval between the scheduled blowing periods of the second converter 22 is excessive compared to the initial period. It becomes shorter, and the interval between the scheduled blowing periods of the fourth converter 24 is excessively longer than the initial period. In addition, the blowing of the third converter 23 has been stopped, and the scheduled period for performing the blowing of the third converter 23 has been eliminated. In this case, the blowing operation of each converter becomes irregular, unlike the initial blowing operation schedule. In particular, during the period from time tc to time td shown in FIG. 3, blowing is not performed in any of the first converter 21, the second converter 22, the third converter 23, and the fourth converter 24. . Therefore, the converter gas 15 is not generated from any converter during this period.

  As described above, as a result of irregularly changing the blow-blowing execution schedule, from a plurality of converters 20 (first converter 21, second converter 22, third converter 23, and fourth converter 24). The generation amount of the converter gas 15 becomes unstable to an extent that cannot be expected from the blowing operation schedule. The operation of each converter in which blowing is performed in accordance with such an irregularly changed blowing schedule is defined as unsteady operation in the present embodiment.

(Converter gas recovery method)
Next, a converter gas recovery method according to an embodiment of the present invention will be described. FIG. 4 is a flowchart showing an example of the converter gas recovery method according to the embodiment of the present invention. In the converter gas recovery method according to the embodiment of the present invention, the converter gas 15 generated by blowing the plurality of converters 20 is recovered and stored in the converter gas holder 2, and the converter gas blower 5 converts the converter gas. The converter gas 15 is supplied from the gas holder 2 to the converter gas combustion facility 30. In this converter gas recovery method, the converter gas recovery apparatus 1 shown in FIG. 1 recovers and stores the converter gas 15 by the converter gas holder 2 and converts the converter gas to the converter gas combustion facility 30 by the converter gas blower 5. In parallel with the supply of 15, each process of steps S101 to S104 shown in FIG.

  Specifically, as shown in FIG. 1, the converter gas recovery apparatus 1 first collects and stores the converter gas 15 from the plurality of converters 20 in the converter gas holder 2 and stores the converter gas 15 in the converter gas holder 2. The planned holder level of the converter gas holder 2 when the converter gas 15 is supplied to the converter gas combustion facility 30 is set (step S101).

  In step S <b> 101, the holder level setting unit 9 a acquires the blowing execution schedule of the plurality of converters 20 from the process computer 25 and acquires the combustion facility operation schedule of the converter gas combustion facility 30 from the process computer 35. Next, the holder level setting unit 9a sets the planned holder level of the converter gas holder 2 based on the acquired blowing execution schedule and the combustion facility operation schedule.

  At this time, the holder level setting unit 9a performs the scheduled blowing start time of the first converter 21, the second converter 22, the third converter 23, and the fourth converter 24 included in the blowing execution schedule, Based on information such as the scheduled end time and the scheduled blowing period, time series data of the generation amount of the converter gas 15 scheduled to be generated from the plurality of converters 20 is calculated. Moreover, the holder level setting part 9a is based on the combustion scheduled period and the amount of combustion of the converter gas 15 of the converter gas combustion equipment 30 (for example, the heating furnace 31 and the coke oven 32) included in the combustion equipment operation schedule. Then, time series data of the supply amount of the converter gas 15 to be supplied to the converter gas combustion facility 30 is calculated.

  Next, the holder level setting unit 9a calculates the difference between the time series data of the calculated generation amount of the converter gas 15 and the time series data of the supply amount in the converter gas holder 2 scheduled along the time series. Calculated as the storage amount of the converter gas 15. Based on the calculation result, the holder level setting unit 9a determines the holder level planned value for the converter gas holder 2 as a holder level that increases or decreases according to the amount of storage of the converter gas 15, that is, the scheduled holder. Calculate the level. The holder level setting unit 9 a sets the planned holder level calculated in this way between the upper limit value Lmax and the lower limit value Lmin of the holder level of the converter gas holder 2.

  After performing step S101 described above, the converter gas recovery apparatus 1 predicts the gas recovery execution period of the converter gas 15 recovered from the plurality of converters 20 into the converter gas holder 2 (step S102). In step S <b> 102, the prediction processing unit 9 b acquires the converter actual operation information of the plurality of converters 20 from the process computer 25. Next, the prediction processing unit 9b performs the blowing of the target converter based on the operation results before and after the start of blowing of the converter (hereinafter referred to as the target converter as appropriate) indicated in the acquired converter actual operation information. The actual smelting start time is calculated, and the gas recovery execution period of the converter gas 15 generated by the blowing starting at the calculated actual blasting start time is predicted.

  Specifically, in step S102, the prediction processing unit 9b, based on the acquired converter actual operation information, the target converter (for example, the first converter) in which the blowing is performed most recently among the plurality of converters 20. 21, at least one of the second converter 22, the third converter 23, and the fourth converter 24). At this time, the prediction processing unit 9b performs the lance insertion time of the target converter and the target converter through the inserted lance as the operation results before the start of blowing, among the operation results before and after the start of blowing of the target converter. Determine the oxygen supply start time. In addition, the prediction processing unit 9b, as an operation result from the start of blowing of the target converter to before the start of converter gas recovery, changes in the gas pressure in the gas recovery pipe 6 and the CO concentration in the gas recovery pipe 6 To grasp the fluctuation time of The gas pressure fluctuation time is the time when the gas pressure in the gas recovery pipe 6 fluctuates beyond a predetermined pressure threshold. The fluctuation time of the CO concentration is the time when the CO concentration of the gas in the gas recovery pipe 6 fluctuates beyond a predetermined concentration threshold.

  Next, the prediction processing unit 9b confirms that the blowing of the target converter has started based on the grasped lance insertion time and the oxygen supply start time. Further, the prediction processing unit 9b determines that the converter gas 15 is generated by blowing the target converter based on the gas pressure change time and the CO concentration change time described above, that is, from the target converter to the converter gas holder. 2 confirms that recovery of the converter gas 15 into 2 has started. Subsequently, the prediction processing unit 9b sets the oxygen supply start time closer to the blowing start time among the lance insertion time and the oxygen supply start time described above, the gas pressure change time, and the CO concentration change time described above. The actual blow start time of the target converter is calculated based on the gas pressure fluctuation time closer to the start time of blowing. That is, the prediction processing unit 9b calculates an intermediate time between the above-described oxygen supply start time and the gas pressure fluctuation time as the actual blowing start time of the target converter.

  After that, the prediction processing unit 9b sets the execution period of the blowing that is started at the actual time of the blowing start calculated as described above, to the blown execution scheduled period nearest to the target converter indicated in the above-described blowing execution schedule. A period with the same time width. Next, the prediction processing unit 9b predicts a period after the above-described CO concentration fluctuation time as a gas recovery execution period of the converter gas 15 generated by the blowing of the target converter among the execution periods of the blowing. .

  After executing the above-described step S102, the converter gas recovery apparatus 1 performs the conversion based on the magnitude relationship between the measured holder level and the planned holder level of the converter gas holder 2 in the gas recovery execution period or non-recovery period predicted in step S102. The furnace gas blower 5 is controlled (step S103). The non-recovery period is a period other than the gas recovery execution period, that is, a period during which recovery of the converter gas 15 into the converter gas holder 2 is not executed.

  In step S <b> 103, the control unit 10 acquires an actual value of the holder level of the converter gas holder 2 by the level meter 3, that is, an actual measured holder level from the level meter 3. Further, the control unit 10 acquires from the computer 9 the scheduled holder level of the converter gas holder 2 set by the holder level setting unit 9a and the gas recovery execution period of the converter gas 15 predicted by the prediction processing unit 9b. . Further, the control unit 10 acquires drive information indicating the current output performance of the converter gas blower 5 from the converter gas blower 5. Based on whether the current time is the gas recovery execution period or the non-recovery period of the converter gas 15 and the magnitude relationship between the measured holder level of the converter gas holder 2 and the planned holder level, the control unit 10 The output of the converter gas blower 5 is controlled.

  Specifically, in step S <b> 103, the control unit 10 determines whether or not the present time is the gas recovery execution period of the converter gas 15. At this time, the control unit 10 determines that the current time is the gas recovery execution period of the converter gas 15 if the current time is within the gas recovery execution period in step S102 described above. In this case, the control unit 10 compares the acquired actual measurement holder level and the planned holder level, and determines the magnitude relationship between the actual measurement holder level and the planned holder level at the current time. As a result of this comparison processing, when the measured holder level is larger than the planned holder level, the control unit 10 calculates the respective time variation amounts of the actual measurement holder level and the planned holder level, and the magnitude of each calculated time variation amount. Judging.

  As a result of the comparison processing described above, in the gas recovery execution period, when the measured holder level is larger than the planned holder level and the time change amount of the measured holder level is larger than the time change amount of the planned holder level, The controller 10 controls the output of the converter gas blower 5 so as to increase the supply amount of the converter gas 15 to the converter gas combustion facility 30. Through the output control of the converter gas blower 5, the control unit 10 performs the gas recovery execution period, that is, the period during which the holder level of the converter gas holder 2 rises as the converter gas 15 is recovered, and the measured holder level reaches the upper limit Lmax. Control which lowers the holder level of converter gas holder 2 is performed so that it may not exceed. At this time, the control unit 10 controls the holder level of the converter gas holder 2 (that is, the storage amount of the converter gas 15 in the converter gas holder 2) so that the measured holder level approaches the planned holder level.

  Based on such control of the control unit 10, the converter gas blower 5 increases the output and increases the supply amount of the converter gas 15 to the converter gas combustion facility 30. At this time, the converter gas 15 may be supplied to the heating furnace 31 with the upper limit of the combustible gas combustible amount of the heating furnace 31, or the coke oven with the upper limit of the converter gas combustible amount of the coke oven 32. 32 may be supplied to the heating furnace 31 and the coke oven 32.

  On the other hand, in step S103, if the current time is outside the gas recovery execution period in step S102 described above, the control unit 10 determines that the current time is a period other than the gas recovery execution period, that is, a non-recovery period. To do. In this case, the control unit 10 compares the acquired actual measurement holder level and the planned holder level, and determines the magnitude relationship between the actual measurement holder level and the planned holder level at the current time. As a result of this comparison processing, when the measured holder level is smaller than the planned holder level, the control unit 10 calculates the respective time change amounts of the measured holder level and the planned holder level, and the magnitude of each calculated time change amount. Judging.

  As a result of the comparison processing described above, in the non-recovery period, the control is performed when the measured holder level is smaller than the planned holder level and the time change amount of the measured holder level is smaller than the time change amount of the planned holder level. The unit 10 controls the output of the converter gas blower 5 so as to reduce the supply amount of the converter gas 15 to the converter gas combustion facility 30. Through the output control of the converter gas blower 5, the control unit 10 determines that the measured holder level is less than the lower limit Lmin during the non-recovery period, that is, the period during which the holder level of the converter gas holder 2 decreases as the converter gas 15 is discharged. In order to prevent this, control for raising the holder level of the converter gas holder 2 is performed. At this time, the control unit 10 controls the holder level of the converter gas holder 2 (that is, the storage amount of the converter gas 15 in the converter gas holder 2) so that the measured holder level approaches the planned holder level.

  Based on such control of the control unit 10, the converter gas blower 5 reduces the output to reduce the supply amount of the converter gas 15 to the converter gas combustion facility 30. At this time, the converter gas 15 may be supplied to the heating furnace 31, may be supplied to the coke oven 32, or may be supplied to the heating furnace 31 and the coke oven according to the operating status of the converter gas combustion facility 30. 32 may be appropriately distributed and supplied.

  Further, when the measured holder level reaches the lower limit value Lmin of the holder level in the non-recovery period, the control unit 10 starts immediately after the non-recovery period from the time when the measured holder level reaches the lower limit value Lmin. The output of the converter gas blower 5 is controlled so as to stop the supply of the converter gas 15 to the converter gas combustion facility 30 until the start time of the gas recovery execution period. At this time, the converter gas blower 5 stops the output based on the control of the control unit 10, thereby stopping the supply of the converter gas 15 to the converter gas combustion facility 30.

  On the other hand, in step S103, the control unit 10 plans to start recovery of the converter gas 15 by the latest blowing scheduled for the target converter according to the start time of the gas recovery execution period in step S102 described above and the blowing execution schedule. Compare the time. As a result of this comparison processing, when the start time of the gas recovery execution period is earlier than the recovery start scheduled time, the control unit 10 determines that the start time of the gas recovery execution period is higher than the above-described blowing operation schedule. Judge that it was early. In this case, the control unit 10 increases the supply amount of the converter gas 15 to the converter gas combustion facility 30, and the measured holder level at the start time of the gas recovery execution period is less than the planned holder level and equal to or more than the lower limit Lmin. In addition, the output of the converter gas blower 5 is controlled.

  Based on such control of the control unit 10, the converter gas blower 5 increases the output and increases the supply amount of the converter gas 15 to the converter gas combustion facility 30. At this time, the converter gas 15 is distributed and supplied to equipment (for example, at least one of the heating furnace 31 and the coke oven 32) that requires the converter gas 15 among the converter gas combustion equipment 30.

  On the other hand, at the time of step S103, the control unit 10 maintains the current supply amount of the converter gas 15 to the converter gas combustion facility 30 when the measured holder level is equal to or lower than the planned holder level during the gas recovery execution period. The output of the converter gas blower 5 is controlled. Further, in the non-recovery period, the control unit 10 outputs the converter gas blower 5 so as to maintain the current supply amount of the converter gas 15 to the converter gas combustion facility 30 when the measured holder level is equal to or higher than the planned holder level. To control.

  After executing step S103 described above, the converter gas recovery apparatus 1 determines whether or not the process is to be terminated (step S104). In step S104, when the instruction information for instructing the end of the process is input by the input unit 8, the control unit 10 determines that the process is terminated (Yes in step S104) and ends the present process.

  On the other hand, the control unit 10 determines that the process is not finished, that is, the process is continued unless the process end instruction information is input from the input unit 8 (No in step S104). In this case, the converter gas recovery apparatus 1 returns to step S102 described above, and repeats the processing after step S102. Moreover, the converter gas collection | recovery apparatus 1 repeats each process of step S101-S104 mentioned above, whenever a blowing execution schedule is input into the computer 9. FIG.

  Next, each process of the converter gas recovery method described above will be specifically described. FIG. 5 is a diagram for specifically explaining each process of the converter gas recovery method according to the embodiment of the present invention. FIG. 5 shows a time transition of the holder level of the converter gas holder 2 and a time transition of the converter operation results of the plurality of converters 20. In FIG. 5, among the time transitions of the holder level of the converter gas holder 2, the solid line indicates the time transition of the actually measured holder level, and the broken line indicates the time transition of the scheduled holder level. Of the converter operation results, “lance insertion” means operation to insert a lance into the converter, and “start oxygen supply” means operation to start supplying oxygen into the converter through the inserted lance. means. “Fluctuation in gas recovery pipe pressure” means an operation for detecting a change in gas pressure in the gas recovery pipe 6, and “Fluctuation in CO concentration” means an operation for detecting a fluctuation in CO concentration in the gas recovery pipe 6. Means.

As shown in FIG. 5, the lance is inserted in the target converter among the plurality of converters 20 (see FIG. 1) before the time t ₁ , and then oxygen supply through the lance is started. It was done. These operations are usually performed sequentially at regular time intervals. Thereafter, a change in gas pressure in the gas recovery pipe 6 leading to the target converter was detected, and then a change in CO concentration in the gas recovery pipe 6 was detected.

  In the operation state described above, the prediction processing unit 9b of the converter gas recovery apparatus 1 acquires from the process computer 25 the operation results of lance insertion and oxygen supply start of the target converter (that is, the operation results before the start of blowing). . The prediction processing unit 9b grasps the lance insertion time and the oxygen supply start time based on the obtained operation results, and based on the grasped time information, the blowing of the target converter has started. Confirm. Thereafter, the prediction processing unit 9b obtains, from the process computer 25, the operation results of the gas pressure fluctuation detection and the CO concentration fluctuation detection in the gas recovery pipe 6 (that is, the operation results after the start of blowing). The prediction processing unit 9b grasps the fluctuation time of the gas pressure and the fluctuation time of the CO concentration in the gas recovery pipe 6 on the basis of the acquired operation results, and from the target converter based on the grasped time information. It is confirmed that the converter gas 15 has been generated.

When the start of the blowing operation of the target converter and the start of generation of the converter gas 15 from the target converter are confirmed, the prediction processing unit 9b determines the supply start time of oxygen and the fluctuation time of the gas pressure ascertained for the target converter. the intermediate time t ₁ and is calculated as a blowing start real time of the target converter. Then, the prediction processing unit 9b, of the blowing execution period that starts the time t _1, the period of the variation time after the CO concentration is predicted as a gas recovery execution period of the converter gas 15. As a result, as shown in FIG. 5, the blowing operation period of the target converter was predicted to be a period in which the actual blowing start time was time t ₁ and the actual blowing end time was time t ₅ . Further, the gas recovery execution period of the blowing operation period was predicted to be a period from time t ₂ to time t ₅ after the CO concentration fluctuation time.

  The respective time widths of the blowing period and the gas recovery period predicted as described above are the time periods of the scheduled blowing period and the planned gas recovery period scheduled for the target converter based on the blowing period schedule. And the same for each. In addition, the prediction results of the blowing period and the gas recovery period coincided with the actual operation of the target converter.

Here, the control unit 10 of the converter gas recovery apparatus 1 sets the start time (time t ₂ ) of the gas recovery execution period, the scheduled start time (time t ₄ ) of the scheduled gas recovery period based on the blowing execution schedule, and Compare As a result of this comparison processing, since the start time of the gas recovery execution period is earlier than the scheduled start time of the gas recovery scheduled period, the control unit 10 sets the start time of the gas recovery execution period to the blowing execution schedule. It is judged that it has become earlier than that. Specifically, as shown in FIG. 5, the actual blowing start time is advanced from time t ₃ to time t ₁ , and accordingly, the start time of the gas recovery execution period is changed from time t ₄ to time t ₂ . accelerated, the end time of the gas recovery execution period was prematurely from time t ₆ to time t _5.

In this case, the control unit 10 increases the supply amount of the converter gas 15 to the converter gas combustion facility 30 during the period from the present time to time t ₂ , and at the actual measurement holder at the start time (time t ₂ ) of the gas recovery execution period. The output of the converter gas blower 5 is controlled so that the level is less than the planned holder level and equal to or more than the lower limit Lmin. Further, as shown in FIG. 5, in the gas recovery execution period from time t ₂ to time t ₅ , the measured holder level is less than or equal to the planned holder level, or the time change amount of the measured holder level is the time of the planned holder level. Less than the amount of change. In such a situation, the control unit 10 controls the output of the converter gas blower 5 so as to maintain the current supply amount of the converter gas 15 to the converter gas combustion facility 30.

After the end time (time t ₅ ) of the gas recovery execution period described above, the prediction processing unit 9b repeatedly executes the prediction process of the gas recovery execution period similarly to the case before time t ₅ . As a result, the prediction processing section 9b, as shown in FIG. 5, predict the interval from time t ₇ to the time t ₁₀ as blowing execution period of the object converter, of the blowing execution period, the time t ₈ To the time t ₁₀ was predicted as the gas recovery execution period. In this case, the predicted blowing operation period and the gas recovery execution period are the same as the scheduled blowing period and the scheduled gas recovery period based on the blowing operation schedule, respectively, and coincided with the actual operation of the target converter.

The control unit 10 has not recovered the converter gas 15 during the period from the end time (time t ₅ ) of the previous gas recovery execution period to the start time (time t ₇ ) of the current gas recovery execution period. Judged as non-collection period. In this non-recovery period, the time change amount of the measured holder level is equal to or greater than the time change amount of the planned holder level as shown in FIG. Therefore, the control unit 10 controls the output of the converter gas blower 5 so as to maintain the current supply amount of the converter gas 15 to the converter gas combustion facility 30 during this non-recovery period.

On the other hand, in the gas recovery execution period from time t ₈ to time t ₁₀ , as shown in FIG. 5, the measured holder level is larger than the planned holder level, and the time change amount of the measured holder level is the planned holder level. Larger than the amount of time change. That is, if this condition is maintained, the measured holder level at time t _9, reaches the upper limit value Lmax of the holder levels of the converter gas holder 2, and finally, outweighs the upper limit value Lmax.

  In order to avoid this situation, the control unit 10 controls the output of the converter gas blower 5 so as to increase the supply amount of the converter gas 15 to the converter gas combustion facility 30 during the gas recovery execution period. By controlling the output of the converter gas blower 5, the control unit 10 adjusts the storage amount of the converter gas 15 in the converter gas holder 2 and corrects and controls the holder level of the converter gas holder 2 to the upper limit value Lmax or less. As a result, as shown in FIG. 5, the actually measured holder level was lowered to the same level as the planned holder level without exceeding the upper limit Lmax.

On the other hand, after the end time (time t ₁₀ ) of the gas recovery execution period described above, a trouble occurs in the steel factory, and the influence of this trouble causes the start of oxygen supply in the target converter as shown in FIG. , I was unexpectedly delayed from the lance insertion. The prediction processing unit 9b executes a prediction process of the gas recovery execution period in response to such actual operational troubles.

That is, the prediction processing unit 9b grasps the lance insertion time based on the operation result of the lance insertion. Thereafter, the prediction processing unit 9b acquires the operation results of the oxygen supply started very late compared to the normal after the insertion of the lance, and based on the acquired operation results, the oxygen supply start that was delayed is started. Know the time. Next, the prediction processing unit 9b grasps the gas pressure fluctuation time and the CO concentration fluctuation time in the gas recovery pipe 6, and an intermediate time t between the grasped oxygen supply start time and the gas pressure fluctuation time. ₁₃ was calculated as the actual blowing start time of the target converter. Subsequently, the prediction processing unit 9b, of the blowing execution period that starts the time t _13, predicted period fluctuation time after the CO concentration as a gas recovery execution period. As a result, as shown in FIG. 5, blowing start real time of the target converter is expected to time t _13, the start time of the gas recovery execution period is estimated to time t ₁₄ of the variation time after the CO concentration It was.

  The respective time widths of the blowing period and the gas recovery period predicted as described above are the same as the respective time widths of the scheduled conversion period and the gas recovery period of the target converter based on the blowing process schedule. . In addition, the prediction results of the blowing period and the gas recovery period coincided with the actual operation of the target converter.

Here, the control unit 10 compares the start time (time t ₁₄ ) of this gas recovery execution period with the scheduled start time (time t ₁₂ ) of the scheduled gas recovery period based on the blowing execution schedule. As a result of this comparison processing, the start time of the gas recovery execution period is later than the scheduled start time of the gas recovery scheduled period. Judged that it was slower.

Next, the control unit 10 determines that the period from the end time (time t ₁₀ ) of the previous gas recovery execution period to the start time (time t ₁₄ ) of the current gas recovery execution period is a non-recovery period. In this non-recovery period, as shown in FIG. 5, the measured holder level is smaller than the planned holder level, and the time change amount of the measured holder level is smaller than the time change amount of the planned holder level. That is, if this condition is maintained, the measured holder level at time t _11, reaches the lower limit value Lmin of the holder levels of the converter gas holder 2, and finally, falls below the lower limit value Lmin.

  In such a non-recovery period, the control unit 10 controls the output of the converter gas blower 5 so as to reduce the supply amount of the converter gas 15 to the converter gas combustion facility 30. By controlling the output of the converter gas blower 5, the control unit 10 adjusts the storage amount of the converter gas 15 in the converter gas holder 2, and sets the holder level of the converter gas holder 2 as shown in FIG. Correction control is performed so that the level approaches the planned holder level.

Despite performs control of the holder levels as described above, measured holder level, as shown in FIG. 5, it has reached the lower limit value Lmin at time t _13. In this case, the control unit 10 changes the period from the time when the measured holder level reaches the lower limit Lmin (time t ₁₃ ) to the start time (time t ₁₄ ) of the gas recovery execution period that starts immediately before this time. The output of the converter gas blower 5 is controlled so that the supply of the converter gas 15 to the furnace gas combustion facility 30 is stopped.

Thereafter, the control unit 10, at the start gas recovered execution period from the time t _14, and compares the measured holder level scheduled holder level. As a result of this comparison processing, as shown in FIG. 5, since the measured holder level is equal to or less than the planned holder level, the control unit 10 restarts the supply of the converter gas 15 to the converter gas combustion facility 30 and the measured holder level. The output of the converter gas blower 5 is controlled so that the level rises toward the planned holder level.

  As described above, in the embodiment of the present invention, the converter gas generated by the blowing of the converter is collected and stored in the converter gas holder, and the converter gas blower is used to recover the converter gas from the converter gas holder. When supplying the converter gas to the gas combustion facility, the planned holder level of the converter gas holder is set between the upper limit value and the lower limit value of the holder level based on the blowing schedule of the converter and the operation schedule of the converter gas combustion facility. The actual converter start time is calculated based on the operation results before and after the start of the converter blowing, and the converter generated by the blowing that starts at the calculated actual blow start time. The converter gas blower is controlled based on the magnitude relationship between the measured holder level of the converter gas holder and the planned holder level, taking into account whether the gas recovery execution period of the gas is present and whether the current is the gas recovery execution period. ing.

  That is, in the gas recovery execution period, when the actually measured holder level by the level meter is larger than the scheduled holder level and the time change amount of the measured holder level is larger than the time change amount of the scheduled holder level, the converter The output of the converter gas blower is controlled to increase the amount of converter gas supplied to the gas combustion facility. In the non-recovery period, if the measured holder level is smaller than the planned holder level and the time change amount of the measured holder level is smaller than the time change amount of the planned holder level, the converter gas combustion facility is The output of the converter gas blower is controlled to reduce the amount of converter gas supply.

  For this reason, it is possible to accurately predict the actual period in which the converter gas generated from the converter during the blowing process is recovered in the converter gas holder, that is, the gas recovery execution period. Even if there is a large variation in the timing of the blowing of the converter due to this, the predicted gas recovery execution period is accurately matched with the period from the converter gas recovery start time to the recovery end time in the actual operation of the converter be able to. As a result, the recovery amount of the converter gas in the converter gas holder can be accurately grasped in a time series. Therefore, the converter in the converter gas holder is added with the recovery amount and supply amount of the converter gas described above. The amount of stored gas, that is, the holder level of the converter gas holder can be appropriately controlled. Therefore, it is possible to avoid as much as possible the situation where the amount of recovered converter gas in the converter gas holder is excessive or too small relative to the amount of converter gas supplied to the converter gas combustion facility. While ensuring stable operation of the furnace gas recovery, it is possible to efficiently recover the converter gas while suppressing the emission of the converter gas as much as possible.

  In the embodiment of the present invention, when the measured holder level reaches the lower limit value of the holder level in the non-recovery period, the period from the time when the lower limit value is reached to the start time of the latest gas recovery execution period, the converter The output of the converter gas blower is controlled so as to stop the supply of the converter gas to the gas combustion facility. For this reason, the drive of the converter gas blower can be urgently stopped before the piston in the converter gas holder is excessively lowered and landing. Thereby, the equipment destruction of the converter gas holder by the landing of this piston can be prevented beforehand.

  In the above-described embodiment, the first converter 21, the second converter 22, the third converter 23, and the fourth converter are used as the converter that generates the converter gas 15 collected in the converter gas holder 2. Although four converters of the furnace 24 are illustrated, the present invention is not limited to this. The number (number of installations) of converters that generate the converter gas 15 to be collected is not limited to four, and may be one or two or more. That is, in the present invention, the number of converters installed is not particularly limited.

  Moreover, in embodiment mentioned above, although the heating furnace 31 and the coke oven 32 which heat a to-be-rolled material were illustrated as the converter gas combustion equipment 30 which operates using the converter gas 15 as a fuel, this invention However, the present invention is not limited to this. The converter gas combustion facility 30 may be, for example, either the heating furnace 31 or the coke oven 32, or a power generation facility that uses the converter gas 15 to generate electric power, for example, other than the heating furnace 31 and the coke oven 32. These facilities may be used, or a combination of these may be used. That is, in the present invention, the type and number of converter gas combustion facilities 30 are not particularly limited.

  Further, in the above-described embodiment, as the operations before and after the start of blowing in the converter, the lance insertion, the oxygen supply start, the gas pressure fluctuation detection in the gas recovery pipe and the CO concentration fluctuation detection are exemplified. The invention is not limited to this. In the present invention, the operation before and after the start of blowing in the converter is not limited to that described above, and may be an operation that is performed before and after the start of blowing in the converter.

  Further, the present invention is not limited by the above-described embodiment, and the present invention includes a configuration in which the above-described constituent elements are appropriately combined. In addition, all other embodiments, examples, operation techniques, and the like made by those skilled in the art based on the above-described embodiments are included in the present invention.

DESCRIPTION OF SYMBOLS 1 Converter gas recovery apparatus 2 Converter gas holder 3 Level meter 4 Combustion / dissipation tower 5 Converter gas blower 6 Gas recovery piping 7 Gas supply piping 8 Input part 9 Computer 9a Holder level setting part 9b Prediction processing part 10 Control part 15 Converter gas 20 Multiple Converters 21 First Converter 22 Second Converter 23 Third Converter 24 Fourth Converter 25, 35 Process Computer 30 Converter Gas Combustion Equipment 31 Heating Furnace 32 Coke Oven

Claims (6)

A converter gas holder for collecting and storing converter gas generated by blowing the converter;
A level meter that measures a holder level that increases or decreases according to the amount of storage of the converter gas in the converter gas holder;
A converter gas blower for supplying the converter gas from the converter gas holder to a converter gas combustion facility;
Based on the conversion blowing schedule of the converter and the operation schedule of the converter gas combustion facility, the expected value of the holder level planned for the converter gas holder is set to the upper limit value and the lower limit value of the holder level. A holder level setting section to be set between,
Based on the operation results before and after the start of blowing of the converter, an intermediate time between the time of actual operation before the start of blowing of the converter and the time of actual operation after the start of blowing of the converter is Calculated as the actual blowing start time of the converter, and the duration of the same time width as the scheduled blowing execution period of the converter shown in the blowing execution schedule from the actual blowing start time The period after the time of actual operation after the start of the blowing of the converter in the period of the blowing is started by the blowing that is started at the actual time of starting the blowing. A prediction processing unit that predicts a gas recovery execution period of the converter gas that is generated;
In the gas recovery execution period, the measured value of the holder level measured by the level meter is larger than the scheduled value of the holder level, and the time variation of the measured value of the holder level is the planned value of the holder level. time is greater than the amount of change, the converter the converter the converter gas blower as measured value of the holder levels increase or to the supply amount of the gas approaches the expected value of the holder levels for gas combustion equipment In the non-recovery period other than the gas recovery execution period, the measured value of the holder level is smaller than the scheduled value of the holder level, and the time change amount of the measured value of the holder level If There smaller than the time variation amount of the expected value of the holder levels, measured in the holder levels to reduce the supply amount of the converter gas for the converter gas combustion equipment A control unit but for controlling the output of the converter gas blower so as to approach the predetermined value of the holder level,
A converter gas recovery apparatus comprising:   When the measured value of the holder level reaches the lower limit value of the holder level during the non-recovery period, the control unit recovers the gas from the time when the measured value of the holder level reaches the lower limit value of the holder level. 2. The converter gas according to claim 1, wherein an output of the converter gas blower is controlled so that supply of the converter gas to the converter gas combustion facility is stopped during a period until a start time of an execution period. Recovery device.   The control unit increases the supply amount of the converter gas to the converter gas combustion facility when the start time of the gas recovery execution period is earlier than the blowing operation schedule, and the gas recovery execution period 3. The output of the converter gas blower is controlled so that the measured value of the holder level at the start time is less than a predetermined value of the holder level and equal to or more than a lower limit value of the holder level. Converter gas recovery device described in 1. Converter gas recovery method for recovering and storing converter gas generated by blowing a converter in a converter gas holder and supplying the converter gas from the converter gas holder to the converter gas combustion facility by a converter gas blower In
Based on the blowing operation schedule of the converter and the operation schedule of the converter gas combustion facility, the converter gas holder is scheduled as a holder level that increases or decreases depending on the storage amount of the converter gas in the converter gas holder. A setting process step for setting a predetermined value of the holder level between an upper limit value and a lower limit value of the holder level;
Based on the operation results before and after the start of blowing of the converter, an intermediate time between the time of actual operation before the start of blowing of the converter and the time of actual operation after the start of blowing of the converter is Calculated as the actual blowing start time of the converter, and the duration of the same time width as the scheduled blowing execution period of the converter shown in the blowing execution schedule from the actual blowing start time The period after the time of actual operation after the start of the blowing of the converter in the period of the blowing is started by the blowing that is started at the actual time of starting the blowing. A prediction processing step for predicting a gas recovery execution period of the converter gas to be generated;
In the gas recovery execution period, the measured value of the holder level measured by a level meter is larger than the scheduled value of the holder level, and the time variation of the measured value of the holder level is the time of the scheduled value of the holder level. If larger than the amount of change, the converter actual value of the holder levels increase or to the supply amount of gas of the converter gas blower so as to approach the predetermined value of the holder level for the converter gas combustion equipment In the non-recovery period other than the gas recovery execution period by controlling the output, the actual measured value of the holder level is smaller than the scheduled value of the holder level, and the time change amount of the actual measured value of the holder level is If smaller than the time variation amount of the expected value of the holder levels, measured values of the holder levels to reduce the supply amount of the converter gas for the converter gas combustion equipment A control step for controlling the output of the converter gas blower so as to approach the predetermined value of the serial holder levels,
A converter gas recovery method comprising:   When the measured value of the holder level reaches the lower limit value of the holder level during the non-recovery period, the control step is configured to recover the gas from the time when the measured value of the holder level reaches the lower limit value of the holder level. 5. The converter gas according to claim 4, wherein an output of the converter gas blower is controlled so that supply of the converter gas to the converter gas combustion facility is stopped during a period up to a start time of an execution period. Collection method.   The control step increases the supply amount of the converter gas to the converter gas combustion facility when the start time of the gas recovery execution period is earlier than the blowing execution schedule, and the gas recovery execution period 6. The output of the converter gas blower is controlled so that an actual measurement value of the holder level at a start time is less than a predetermined value of the holder level and is not less than a lower limit value of the holder level. The converter gas recovery method described in 1.

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