JP2005281719A - Dust collecting facility for blast furnace and driving method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dust collecting facility for blast furnace and a driving method therefor with which a delayed control is not caused and the energy saving control in the whole process can be attained. <P>SOLUTION: This dust collecting facility is constituted of: dust collecting fans 7 for sucking the dust-containing air through dust collecting ducts 5 and dust collecting filters 6 from dust collecting hoods 3 arranged in a plurality of dust-developing positions on a casting floor in the blast furnace, respectively; motor-driven dampers 8 arranged in the dust collecting ducts 5 near the dust collecting hoods, respectively; variable speed driving devices for performing variable speed driving of the dust collecting fans 7; and controllers 11 for controlling the motor-driven dampers 8 and the variable speed driving devices. The controller 11 performs automatic opening/closing control of the motor-driven damper 8 and speed-control of the variable speed driving device, according to a changing signal in each process of pig iron tapping wait, tapping hole open, pig iron tapping-off and tapping hole close, in each operational process on the casting floor in the blast furnace. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a dust collection facility for a blast furnace and an operation method thereof, and more particularly, to a dust collection facility for a blast furnace and an operation method thereof that reduce energy consumption of the facility.

  Conventionally, in order to make the dust generated when the blast furnace comes out harmless, and to maintain a good work environment, dust collection ducts are extended from multiple dust generation locations on the cast floor, and a dust collection filter is installed. A method of sucking dust-containing air with a dust collecting fan is used. An electric damper is installed at the end of each dust collection duct near the dust generation location, and the opening degree of the electric damper is adjusted according to the dust generation state. Some devices have been devised, such as adjusting the rotational speed of the dust collection fan according to the amount of dust.

Specifically, a fine pressure gauge is provided at the end of each dust collection duct near the dust generation location, the opening of the electric damper is adjusted according to the signal of this fine pressure gauge, and the open / close state of the entire electric damper is A method for adjusting the rotational speed of the dust collecting fan (see, for example, Patent Document 1), and a method for adjusting the rotational speed of the dust collecting fan so that the atmospheric pressure in the desiliconization pit becomes a predetermined value (for example, Patent Document 2). Further, a method of adjusting the rotational speed of the dust collecting fan according to the charging speed of the desiliconizing agent has been proposed (see, for example, Patent Document 3).
JP-A-63-178815 (second page, FIG. 1) JP-A-11-279607 (page 2-3, FIG. 1) JP 2000-256315 A (page 3, FIG. 2)

  In the methods disclosed in Patent Document 1 and Patent Document 2, it is premised that the pressure value is measured with high accuracy. However, since the target pressure level is low, it is difficult to measure with sufficient accuracy. In order to perform stable control, it is necessary to take a large control time constant, which causes problems such as control delay. Moreover, since the method shown by patent document 3 makes control object only the local part of the work process of a blast furnace like the method shown by patent document 2, it is a subject in the meaning of the efficient energy-saving control of the whole dust collection equipment. was there.

  The present invention has been made in view of the above, and an object of the present invention is to provide a dust collection facility for a blast furnace and a method for operating the same, which can control energy saving of the entire process without any control delay.

  In order to achieve the above object, the blast furnace dust collection equipment and the operating method thereof according to the present invention include a dust collection hood provided at each of a plurality of dust generation locations of the blast furnace casting floor through a dust collection duct and a dust collection filter. A dust collecting fan for sucking dust air; an electric damper provided in a dust collecting duct in the vicinity of the dust collecting hood; a variable speed driving device for driving the dust collecting fan at a variable speed; the electric damper; And a controller for controlling the speed change drive device. The controller is configured to control the electric damper according to a transition signal in each process of waiting for opening, opening, opening and closing in each operation process of the blast furnace casting floor. Automatic opening / closing control and speed control of the variable speed drive device are performed.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the dust collection equipment for blast furnaces which does not have a control delay, and can perform the energy saving control of the whole process, and its operating method.

  Embodiments of the present invention will be described below with reference to the drawings.

  A blast furnace dust collection facility and an operation method thereof according to Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 1 is a configuration diagram of a blast furnace dust collection facility according to the present invention.

  The blast furnace 1 obtains molten iron by reacting iron ore and coke at a high temperature. The hot metal is periodically discharged from a tap outlet 1A provided in the blast furnace 1, and flows out through the hot metal 2 formed of a refractory provided in the blast furnace casting floor. The hot metal 2 is covered with a cover for prevention of dust scattering and safety. A dust collection hood 3 for local dust collection is provided by connecting to a cover at a location where dust generation is particularly large in the flow path of the hot metal 2, and a dust collection duct 5 is extended to the dust collection hood 3 to collect the dust. Dust air is sucked by the dust collecting fan 7 through the dust collecting filter 6 from the part where the dust duct 5 is joined, and the purified air is discharged to the outdoor part of the building. An electric damper 8 is provided in the dust collecting duct 5 in the vicinity of the dust collecting hood 3, and the flow rate of the dust collecting duct 5 can be adjusted by opening and closing the electric damper 8. The tap outlet from the blast furnace 1 is also provided on the blast furnace wall on the opposite side of the illustrated tap outlet 1A, and the same equipment as described above is arranged on the blast furnace casting floor on the opposite side across the blast furnace 1, Usually, the dredging operation is performed by alternately using the equipment of FIG. 1 and the equipment on the opposite side, but the illustration of this portion is omitted. Further, although another tap opening may be provided adjacent to the tap opening 1A, the illustration is omitted.

  The dust collection hood 3 </ b> A is provided at the outlet, and an electric damper 8 </ b> A is installed in the adjacent dust collection duct 5. In order to perform the work with the cover of the hot metal 2 partially opened at the time of opening and closing, the upper dust collecting hood 4 is provided at the upper part of the tap outlet, and the dust collecting adjacent to the upper dust collecting hood 4 is used. An electric damper 8E is installed in the dust duct 5 to collect dust. The electric damper 8E in this case basically performs an opening / closing operation similar to that of the electric damper 8A, but the upper dust collection hood 4 and the electric damper 8E are not necessarily installed.

  The dust collection hood 3B is provided in the skinmer portion, and an electric damper 8B is installed in the adjacent dust collection duct 5. Skinmer separates hot metal flowing from hot metal 2 into pig iron and slag. The dust collection hood 3 </ b> C is provided on the tilting rod, and an electric damper 8 </ b> C is installed in the adjacent dust collection duct 5. The tilting iron is a place where the pig iron separated by skinmers is poured into a transport vehicle called a torpedo car waiting in the lower part of the casting floor. The dust collection hood 3D is provided in the slag runner portion, and an electric damper 8D is installed in the adjacent dust collection duct 5.

  The dust collection fan 7 is driven by an AC motor 9, and the AC motor 9 is supplied with AC power of variable frequency from an inverter 10.

  The controller 11 controls the energy-saving operation of the blast furnace dust collection facility including the dust collection hood 3, the dust collection duct 5, the electric damper 8, the dust collection filter 6, the dust collection fan 7, the AC motor 9, and the inverter 10. . This control gives an opening / closing command of the electric damper 8 and a speed command of the AC motor 9 to the inverter 10 according to a process transition signal of a series of operation processes.

  Hereinafter, according to the energy-saving operation chart of the blast furnace dust collection facility shown in FIG. 2, the detailed operation and effect of the blast furnace dust collection facility and the operation method according to the present invention will be described. In FIG. 2, the opening / closing operation of the electric damper of the slag runner portion is basically the same as the opening / closing operation of the electric damper of the tilting rod portion, and therefore illustration thereof is omitted.

  First, the spear waiting stage, which is the first operation process, will be described. In this waiting stage, it is usual that the leaving operation is performed with the equipment on the opposite side across the blast furnace 1 as described above. Since the dust generation amount of the cast floor is extremely small in this waiting stage, the electric dampers 8A, 8B, 8C and 8D provided at the outlet, skinmer, tilting rod and slag runner are closed. In accordance with this, the rotational speed of the dust collecting fan 7 is set to the lowest level 1.

  Next, the opening stage which is the second operation process will be described. In this hole opening stage, a hole opening machine is set in the tap hole 1A, and the mud filled at the time of closing is excavated by this hole opening machine to open the hole. At this time, the hot metal in the furnace begins to flow out and generates dust. Therefore, the electric damper 8A provided in the vicinity of the outlet is opened, and the rotational speed of the dust collecting fan 7 is increased to level 2 corresponding to the increase in the air volume due to the opening of the electric damper 8A. The transition condition of the operation process from the waiting stage to the opening stage takes into account the operation signal of the opening machine or the time delay until opening, and the delay time of several seconds to several tens of seconds is added to the opening machine operation signal. The signal is added.

  Next, an output stage that is the third operation process will be described. In this unloading stage, the hot metal flowing out at the opening stage is separated from the slag by the skinmer, and the pig iron is poured into the torpedo car from the tilting iron, and the slag flows through the slag runner and the slag treatment is performed. Normally, the transition signal of the process to the output stage is a push button signal for starting the output of the worker, but it may be a signal obtained by delaying the operation signal of the above-mentioned opening machine for a predetermined time.

  In this tapping stage, since dust is generated from all parts of the cast floor, the electric dampers 8A, 8B, 8C provided in the tapping outlet, skinmer, tilting rod and slag runner part, respectively. All the 8Ds are opened, and the rotational speed of the dust collecting fan 7 is increased to a level 3 higher than the level 2 corresponding to the increase in the air volume by opening all the electric dampers. This level 3 is usually a speed close to the rated speed of the AC motor 9, but this is not limited depending on the capacity of the dust collecting fan.

  Finally, the closing stage as the fourth operation process will be described. In this closing stage, a mud gun is installed at the spout, and the mud is filled with the mud gun to close the spout. When the spout is blocked by mud, the hot metal outflow from the spout ends, so that no dust is generated near the spout. At this time, the hot metal that has flowed out before closing the spout has flowed to the skinmer, the tilting iron and the slag runner for a while, but this flow ends after a certain period of time. When this flow is finished and the process after the extraction such as residue removal is completed, the process returns to the output waiting stage as the first operation process.

  In this closed stage, the electric damper 8A provided at the outlet is closed, and the rotational speed of the dust collecting fan 7 is lowered to level 4 corresponding to the reduction in the air volume due to the closing of the electric damper 8A. . The transition signal of the operation process from the output stage to the blockage stage is a signal obtained by adding a delay time of several seconds to several tens of seconds to the operation signal of the mud gun, considering the time delay until the mud operation signal or the mud filling. To do. Further, the transition signal of the operation process from the closing stage to the waiting stage is a signal obtained by adding a time delay by a timer to a closing completion pushbutton signal of an operator or a mud gun operation end signal.

  If the operation of the blast furnace dust collection equipment is performed according to the energy saving operation chart of the blast furnace dust collection equipment shown in FIG. 2 above, automatic opening / closing control of the electric damper is performed without time delay according to the dust generation location of each operation process, Since the rotational speed of the dust collecting fan can be controlled automatically and finely according to the minimum air volume of the dust collecting duct, it is possible to achieve a significant energy saving effect compared to the conventional case.

  FIG. 3 is a configuration diagram of a blast furnace dust collection facility according to Embodiment 2 of the present invention. About each part of this Example 2, the same part as each part of the dust collection equipment for blast furnaces concerning Example 1 of FIG. 1 is shown with the same code | symbol, and the description is abbreviate | omitted. The second embodiment differs from the first embodiment in that building dust collecting hoods 12A and 12B are provided in the upper part of the blast furnace building, and are extended to the dust collecting duct 5A via electric dampers 8F and 8G, respectively. The dust-containing air is sucked from the dust duct 5A through the dust collection filter 6A by the dust collection fan 7A that is driven at a variable speed by the inverter 10A and the AC motor 9B.

  As described above, the brewing of the blast furnace 1 is performed using the first facility for obtaining hot metal from the brewing port 1A shown in FIG. 3 and the second facility for obtaining hot metal from the brewing port on the opposite side across the blast furnace 1. Are used alternately. The building dust collecting hoods 12A and 12B are for sucking dust scattered in the building, and correspond to the first facility and the second facility, respectively. Therefore, normally, the electric damper 8F is opened and the electric damper 8G is closed during the output in the first facility, and the electric damper 8F is closed and the electric damper 8G is opened during the output in the second facility. However, considering that dust increases immediately after the opening operation and immediately after the closing operation, a period in which both the electric damper 8F and the electric damper 8G are open is provided in a transition period including a period in which the dust increases. It is a preferable operation pattern that the dust collection fan 7A is operated at the maximum speed during the period and the speed of the dust collection fan 7A is decreased during the period when the output in the first or second facility is stable. In this case, it is not always necessary to provide a period during which both the electric damper 8F and the electric damper 8G are open.

  As explained above, if the opening and closing control of the electric damper of the dust collection equipment provided for the building and the speed control of the dust collection fan are also performed, energy saving operation of the finer dust collection equipment for the blast furnace will be performed. Can be done.

  A third embodiment of the present invention will be described below with reference to FIGS.

  FIG. 4 is an energy saving operation chart of the blast furnace dust collecting facility according to the third embodiment of the present invention. The difference between the fourth embodiment and the energy saving operation chart of the blast furnace dust collecting facility according to the first embodiment of FIG. 2 is that the opening stage is divided into two parts: a drilling stage (pre-process) and an opening stage (post-process). In the previous excavation stage, the rotational speed of the dust collecting fan 7 is set to level 5 which is an intermediate value between level 1 and level 2.

  As described above, the hot metal does not flow out in the excavation stage in the initial stage of the drilling operation, but there is some dust generation associated with the excavation. Therefore, if the rotational speed of the dust collecting fan 7 is set to level 5, which is an intermediate value between level 1 and level 2, energy consumption can be reduced in the excavation stage in the preceding process.

  Embodiment 4 of the present invention will be described below with reference to FIGS.

  FIG. 5 is an energy saving operation chart of the blast furnace dust collecting facility according to the fourth embodiment of the present invention. The difference between the fourth embodiment and the energy-saving operation chart of the blast furnace dust collecting facility according to the first embodiment shown in FIG. 2 is that the rotational speed of the dust collecting fan 7 after the initial stage of the extraction stage is proportional to the output amount. This is the point to be controlled.

  In the initial stage of the extraction stage, the amount of dust generation is large, and after a certain period of time, this dust generation stops and stabilizes to a low level. The amount of dust generated after the initial stage is completed is approximately proportional to the flow rate of the hot metal and tends to gradually increase with the lapse of time of the brewing. On the other hand, since the amount of hot metal produced is measured and managed by a torpedo car weighing machine or a hot metal level meter, it is possible to obtain a signal of the amount of molten iron per unit time by any one of these output signals.

  Therefore, at the initial stage of the extraction stage, the rotational speed of the dust collection fan 7 is set to level 3, and after the initial stage is completed, the rotational speed of the dust collection fan 7 is approximately proportional to the output amount per unit time. If controlled, the energy consumption can be further reduced after the initial stage of the output stage. The initial stage end signal may be a predetermined delay time added to the output start signal, for example, and after the initial stage end, the rotational speed of the dust collecting fan 7 is at the maximum expected output amount. What is necessary is just to perform the speed control to be level 3.

The block diagram of the dust collection equipment for blast furnaces based on Example 1 of this invention. The energy saving operation chart of the dust collection equipment for blast furnaces concerning Example 1 of the present invention. The block diagram of the dust collection equipment for blast furnaces based on Example 2 of this invention. The energy-saving operation chart of the dust collection equipment for blast furnaces concerning Example 3 of this invention. The energy-saving operation chart of the dust collection equipment for blast furnaces based on Example 4 of this invention.

Explanation of symbols

1 Blast furnace 1A Outlet 2 Hot metal 3, 3A, 3B, 3C, 3D Dust collection hood 4 Upper dust collection hood 5, 5A Dust collection ducts 6, 6A, Dust collection filters 7, 7A Dust collection fans 8, 8A, 8B , 8C, 8D, 8E, 8F, 8G Electric damper 9, 9A AC motor 10 Inverter 11 Controller 12A, 12B Dust collection hood for building

Claims (11)

Dust-collecting air is sucked in by a dust collection fan from a dust collection hood provided at each of a plurality of dust generation locations on the blast furnace casting floor through a dust collection duct and a dust collection filter.
An electric damper is provided in each of the dust collection ducts in the vicinity of the dust collection hood,
The dust collecting fan is driven at a variable speed by a variable speed drive device,
The electric damper and the variable speed drive device are controlled by a controller,
The controller is
Depending on the transition signal of each process of waiting for opening, opening, opening and closing in each operation process of blast furnace cast floor,
A method of operating a dust collection facility for a blast furnace, wherein automatic opening / closing control of the electric damper and speed control of the variable speed drive device are performed. Dust-collecting air is sucked in by a dust collection fan from a dust collection hood provided at each of a plurality of dust generation locations on the blast furnace casting floor through a dust collection duct and a dust collection filter.
An electric damper is provided in each of the dust collection ducts in the vicinity of the dust collection hood,
The dust collecting fan is driven at a variable speed by a variable speed drive device,
Dust-containing air is sucked from the multiple dust collection hoods for the building through the dust collection duct and dust collection filter by the dust collection fan for the building,
An electric damper for the building is provided in each of the dust collection ducts near the dust collection hood for the building,
The building dust collecting fan is driven at a variable speed by a building variable speed drive,
The electric damper and the building electric damper and the variable speed drive device and the building variable speed drive device are controlled by a controller,
The controller is
Depending on the transition signal of each process of waiting for opening, opening, opening and closing in each operation process of blast furnace cast floor,
A method of operating a dust collection facility for a blast furnace, wherein automatic opening / closing control of the electric damper and speed control of the variable speed drive device are performed. The transition signal to the opening process is an operation signal of the opening machine,
The transition signal to the brewing process is a signal obtained by delaying the brewing start signal or the operation signal of the opening machine by a predetermined time,
The transition signal to the closing process is a mud gun operation signal,
The operation of the dust collection equipment for a blast furnace according to claim 1 or 2, wherein the transition signal to the unloading waiting process is a closing end signal or a signal obtained by delaying the operation signal of the mud gun for a predetermined time. Method. The controller is
In the waiting process,
The operating method of the blast furnace dust collection equipment according to claim 1 or 2, wherein all the electric dampers are closed and the rotational speed of the dust collection fan is controlled to a predetermined lower limit value. The controller is
In the opening step,
3. The electric damper in the vicinity of the tap opening is opened, and the rotational speed of the dust collecting fan is controlled to be higher than the rotational speed in the tap waiting process. Operation method of dust collection equipment for blast furnace. The controller is
In the step of brewing,
The electric damper in the vicinity of the outlet and the electric damper in the vicinity of the skinmer, the slag runner, and the tilting rod are opened, and the rotational speed of the dust collecting fan is controlled to be higher than the rotational speed in the opening step. The operating method of the dust collection equipment for blast furnaces of Claim 1 or Claim 2. The controller is
In the closing step,
Close the electric damper near the spout, open the skinmer, the slag runner, and the electric damper near the tilting sputum, and set the rotational speed of the dust collecting fan higher than the rotational speed in the spear waiting process, The method of operating a dust collecting facility for a blast furnace according to claim 1 or 2, wherein the speed is controlled to be lower than a rotational speed in the dredging process. The opening step has a pre-process and a post-process,
The controller is
In the previous step,
Opening the electric damper for local dust collection in the electric damper near the outlet, and controlling the rotational speed of the dust collecting fan to be higher than the rotational speed in the waiting process for the extraction,
In the post-process,
The electric damper in the vicinity of the tap opening is opened, and the rotation speed of the dust collecting fan is controlled to be higher than the rotation speed in the previous step and lower than the rotation speed in the taping step. The operating method of the dust collection equipment for blast furnaces of Claim 1 or Claim 2. The controller is
In the step of brewing,
Open the electric damper near the tap and the electric damper near the skinmer, the slag runner, and the tilting rod, and the rotational speed of the dust collecting fan,
The variable speed control is performed to a speed corresponding to the amount of brewing per unit time after a predetermined speed higher than the rotation speed in the opening step for a predetermined time after the start of brewing. Or the operating method of the dust collection equipment for blast furnaces of Claim 2. A dust collection fan that sucks dust-containing air from a dust collection hood provided at each of a plurality of dust generation locations of the blast furnace cast floor through a dust collection duct and a dust collection filter;
Electric dampers respectively provided in a dust collection duct in the vicinity of the dust collection hood;
A variable speed drive for driving the dust collection fan at a variable speed;
A controller for controlling the electric damper and the variable speed drive device;
The controller is
Depending on the transition signal of each process of waiting for opening, opening, opening and closing in each operation process of blast furnace cast floor,
Blast furnace dust collection equipment, wherein automatic opening / closing control of the electric damper and speed control of the variable speed drive device are performed. A dust collection fan that sucks dust-containing air from a dust collection hood provided at each of a plurality of dust generation locations of the blast furnace cast floor through a dust collection duct and a dust collection filter;
Electric dampers respectively provided in a dust collection duct in the vicinity of the dust collection hood;
A variable speed drive for driving the dust collection fan at a variable speed;
A dust collection fan for the building that sucks dust-containing air from a plurality of dust collection hoods for the building through a dust collection duct and a dust collection filter;
Electric dampers for buildings provided in dust collection ducts in the vicinity of the dust collection hood for the buildings,
A variable speed drive device for building that drives the dust collecting fan for building at a variable speed;
A controller for controlling the electric damper and the building electric damper, the variable speed driving device, and the building variable speed driving device;
The controller is
Depending on the transition signal of each process of waiting for opening, opening, opening and closing in each operation process of blast furnace cast floor,
Blast furnace dust collection equipment, wherein automatic opening / closing control of the electric damper and the building electric damper and speed control of the variable speed driving device and the building variable speed driving device are performed.

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