JP5441730B2 - Profile measuring device for blast furnace interior - Google Patents

Description

  The present invention relates to an apparatus for measuring the shape (profile) of the surface of a blast furnace interior.

  In general, blast furnaces in the production of pig iron are alternately charged with sintered ore or lump iron ore (hereinafter simply referred to as iron ore or ore) and coke as powdered iron ore. As a result, the ore layer and the coke layer are formed in the furnace. The iron ore is heated and reduced (indirect reduction) by the CO gas generated by the reaction between the hot air blown from the tuyere below the blast furnace and coke, and part of the iron ore is reduced directly by the coke and softened and fused. After forming the band, it becomes a droplet. The droplets, that is, the molten iron, pass between the coke layers and accumulate at the bottom of the furnace. The ore layer and coke layer formed in the furnace gradually descend in the furnace.

  In the above process, it is very important to adjust the charge distribution at the top of the furnace formed by the iron ore and coke charged in the blast furnace to obtain an appropriate gas distribution. The profile (surface shape) of the charge at the top of the furnace in the blast furnace is determined by the moving armor in the bell-type charging device and the fall trajectory of the charge through the distribution chute in the bell-less charging device. Usually, the profile of the charge at the top of the furnace has a substantially inverted conical shape with a low center part around the center vertical direction (axial center) of the blast furnace. The profile of the blast furnace interior is important information for the operation of the blast furnace, and a method for measuring the profile of the charge charged and deposited in the furnace has been developed and put into practical use.

  For example, in Patent Document 1, a microwave probe provided with a microwave transmission / reception antenna and a transmission circuit is provided at a position outside the furnace top on the furnace center axis, and the microwave probe is rotated to transmit and receive microwaves. Thus, a measuring device for measuring the surface contour of the charge in the furnace is disclosed.

  Further, for example, in Patent Document 2, a sonde tube having a microwave transmission / reception function is inserted from the side surface of the furnace body toward the blast furnace axis, and the microwave is transmitted toward the blast furnace interior, A method for measuring the distance to the surface of the blast furnace interior is disclosed.

Japanese Patent No. 2870346 JP 2002-275516 A

  However, since the measuring apparatus of Patent Document 1 moves the microwave probe itself to measure the entire profile in the furnace, the apparatus becomes large. Also, a microwave probe equipped with a circuit for transmitting and receiving microwaves may be damaged due to the influence of the furnace environment if installed close to the furnace where various gases and dust are generated at high temperature and high pressure. However, when installed at a position away from the inside of the furnace, there is a problem that a large opening on the blast furnace side of the probe storage case must be provided in order to scan the entire surface of the furnace interior.

  Patent Document 2 also measures by moving the antenna itself. In addition, since the sonde tube is inserted and measured from the side of the furnace body, when the raw material is charged, the sonde tube must be evacuated from the furnace body, and continuous measurement at the time of raw material charging is not possible. is there.

  The object of the present invention is that the structure of the profile measuring device itself is simple, and its mechanical part is not affected by the heat in the blast furnace, high-concentration dust, etc., and the blast furnace interior can carry out highly accurate profile measurement. It is to provide a profile measuring apparatus.

  In order to solve the above problems, the present invention is a profile measuring device that is installed at the top of a blast furnace and measures the profile of the blast furnace interior, and includes a microwave transmitter, an antenna that radiates microwaves, A waveguide that connects the microwave transmitter and the antenna, a reflector that reflects microwaves, a reflector driving device, and a drive shaft that connects the reflector and the reflector driving device. The antenna, the end of the waveguide on the antenna side, the reflector, and the end of the drive shaft on the reflector are installed at the top of the blast furnace and directed into the furnace of the blast furnace. Provided is a blast furnace charge profile measuring device characterized in that it is housed in a pressure-resistant vessel having an opening, and the microwave transmitter and the reflector driving device are arranged outside the pressure-resistant vessel.

In the pressure-resistant container, a reflector housing portion having the opening and an antenna housing portion are partitioned by a microwave transmitting member, and the antenna is disposed facing the microwave transmitting member in the antenna housing portion. The

  Further, the present invention is a profile measuring device that is installed at the top of a blast furnace and measures the profile of the blast furnace interior, and includes a microwave transmitter, an antenna that radiates microwaves, and the microwave transmitter. A waveguide that couples the antenna; a reflector that reflects microwaves; a reflector drive; and a drive shaft that couples the reflector and the reflector drive; And the end of the drive shaft on the reflector side is housed in a pressure-resistant vessel that is installed at the top of the blast furnace and has an opening toward the furnace of the blast furnace, the antenna, the waveguide, A microwave transmitter and a reflector driving device are disposed outside the pressure-resistant container, and the pressure-resistant container has one side wall formed of a microwave transmitting member, and the antenna faces the microwave transmitting member. Arranged Providing profile measuring apparatus of the blast furnace charge, characterized in that.

  The antenna and the drive shaft are arranged so that their central axes coincide with each other, and the reflector is driven at an angle of 45 ° with respect to the central axis of the antenna when viewed from the side of the antenna. The driving shaft is fixed by the reflecting plate driving device so that the microwave radiated from the antenna is reflected by the reflecting plate and scanned in the diameter direction passing through the central axis of the blast furnace on the surface of the blast furnace interior entrance. It is preferable to operate the reflector by rotating the.

  It is preferable that an opening of the pressure vessel is covered with a heat-resistant board having air permeability, and nitrogen is blown into the pressure vessel from the outside of the blast furnace.

  It is preferable that the antenna is a parabolic antenna.

  According to the present invention, even in a blast furnace under high-concentration dust, a mechanical profile of a blast furnace can be measured with high accuracy without affecting the mechanical part such as a vessel. In addition, it is possible to accurately grasp changes in the profile of the charge surface without affecting the operation of blast furnace iron ore and coke charging, etc. Can prevent and stabilize the operation of the blast furnace.

It is a longitudinal cross-sectional view which shows the example of the blast furnace top part provided with the measuring apparatus of this invention. It is the elements on larger scale which show the structure of the measuring apparatus of this invention. It is a schematic diagram of the cross section in the AA cutting line of FIG. It is a schematic diagram of the cross section in the BB cutting line of FIG. It is a side view which shows different embodiment of this invention. It is a side view which shows further another embodiment of this invention. It is a figure which shows the profile of the blast furnace charge measured by this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present specification and drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 shows an example in which the profile measuring device 1 of the present invention is installed in a blast furnace 2. A bell-less charging device 5 is provided at the furnace port, and iron ore and coke are charged into the furnace through the distribution chute 6. In the present embodiment, the profile measuring device 1 is installed at one place near the top of the furnace and outside the furnace body 3. It is obvious that a plurality of the profile measuring devices 1 may be arranged outside the top of the blast furnace 2.

  2 is an enlarged view of the portion of the profile measuring device 1 in FIG. 1, FIG. 3 is a plan view of the profile measuring device 1 as viewed from above, and FIG. 4 is a view from the left side of FIG. 1 is a side view of a profile measuring device 1. FIG. 2 to 4, the profile measuring device 1 is arranged outside the pressure vessel 10 and supports and drives the antenna 11 and the reflection plate 12 accommodated in the pressure vessel 10. , Each mechanism unit to be controlled (for example, the reflector driving device 21 and the drive shaft 22).

  The pressure vessel 10 has an opening 13 facing the inside of the furnace on the bottom surface, and is installed near the top of the blast furnace 2. A heat-resistant board 14 having air permeability is fitted into the opening 13, and a gate valve 15 is provided inside the furnace. The gate valve 15 is opened and closed by the gate valve driving unit 16 and is opened when the profile is measured, and is closed when the blast furnace 2 is stopped, for example. In this way, microwaves can be transmitted through the opening 13 when measuring the profile.

  The antenna 11 is a parabolic antenna having a diameter of about 250 mm, for example, and is connected to a microwave transmitter 18 disposed outside the pressure vessel 10 through a waveguide 17 that penetrates the wall surface of the pressure vessel 10. Therefore, the end portion 17 a on the antenna 11 side of the waveguide 17 is accommodated in the pressure resistant container 10, and the other end side is disposed outside the pressure resistant container 10. In the middle of the waveguide 17 disposed outside the pressure vessel 10, a shutoff valve 19 for shutting off gas or the like inside the blast furnace 2 is provided. The microwave transmitter 18 generates a microwave whose frequency continuously changes in a certain range, and can transmit and receive the microwave. A data processing unit 20 is connected to the microwave transmitter 18 by a signal line. In each figure, the shape of the antenna is simplified.

  A microwave generated by the microwave transmitter 18 having a continuously changing frequency is radiated from the antenna 11 through the reflector 12 toward the measurement target, and receives the microwave (reflected wave) reflected by the measurement target. To detect. In the data processing unit 20, the round-trip time ΔT of the microwave from the antenna to the measurement target (the charge surface) is obtained from the change ΔF in the frequency from the microwave emission to the reception at the antenna 11. The distance from the object to be measured is calculated. This measurement is based on the FMCW (Frequency Modulated Continuous Wave) method (Frequency Modulated Continuous Wave method) that mixes and measures the electrical signal that emits the microwave and the electrical signal that is obtained by receiving the reflected wave from the charged surface. ). A commercially available apparatus may be used for the microwave distance meter of this type. Note that the distance measurement method using microwaves is an example that can be used.

  The transmission frequency band of the microwave used for measurement is 10 GHz or more, preferably about 24 GHz. The higher the frequency, the smaller the antenna 11 can be made. By using the microwave, the profile in the blast furnace 2 can be accurately measured without being affected by the environment such as temperature and dust. Moreover, since the parabolic antenna has high directivity, microwaves can be radiated to a desired position with high accuracy. Furthermore, since the spread of the microwave at the time of radiation | emission is suppressed, since the opening part 13 toward the inside of a furnace can be made small, it is preferable.

  As shown in FIG. 4, the microwave transmission / reception direction (center axis direction) of the antenna 11 is provided in a direction perpendicular to the perpendicular of the opening (surface) 13 of the pressure vessel 10, as shown in FIGS. Further, on the extension of the central axis of the antenna 11, a drive shaft 22 that connects the reflector 12 and the reflector driving device 21 is provided. That is, the drive shaft 22 is provided so that the center axis of the drive shaft 22 coincides with the center axis of the antenna 11. The drive shaft 22 penetrates the wall surface of the pressure vessel 10, the end 22 a on the reflecting plate 12 side is housed in the pressure vessel 10, and the other end is disposed outside the pressure vessel 10. As shown in FIG. 4, the reflector 12 is fixed to the drive shaft 22 at an angle of approximately 45 ° with respect to the central axis of the antenna 11. The reflector 12 is made of, for example, a stainless steel plate, and the area viewed from the front side of the antenna 11 is slightly larger than the antenna 11. Although the shape is not limited, a circular shape is preferable in terms of operability. By rotating the drive shaft 22 around its central axis by the reflector driving device 21, the microwave radiated from the antenna 11 in the direction of the central axis is reflected on the reflector 12 by, for example, a blast furnace as shown in FIG. 2 is reflected toward the inside of the blast furnace 2 and scanned in a diametrical direction passing through the central axis of the blast furnace 2.

  Further, at the time of measurement, in order to prevent gas and dust inside the blast furnace 2 from entering the pressure vessel 10 and to prevent leakage of gas and the like from the pressure vessel 10 to the outside, For example, nitrogen gas is purged to atmospheric pressure +0.4 MPa. Since the air-resistant heat-resistant board 14 is fitted in the opening 13 of the pressure-resistant container 10, nitrogen gas can pass through the furnace, and dust or the like adheres to the inner surface of the heat-resistant board 14. And the antenna 11 and the reflector 12 can be protected from heat in the furnace. As the heat-resistant board 14 having air permeability, for example, a ceramic fiber is commercially available.

  As described above, the antenna 11 and the reflecting plate 12 are accommodated in the pressure vessel 10 and the other mechanical parts are arranged outside the pressure vessel 10 so that they are not affected by gas or heat in the furnace. The circuit and the drive mechanism can be protected.

  Further, for example, as shown in FIG. 4, by making the opening 13 of the pressure device 10 a part of the bottom surface of the pressure device 10 and removing the antenna 11 from the position of the opening 13, the antenna 11 is affected in the blast furnace 2. It can be made difficult to receive.

  In the above embodiment, the reflecting plate 12 is fixed at an angle of 45 ° with respect to the central axis of the antenna 11. Although the present invention is not limited to this, for example, when the mounting angle of the reflecting plate 12 with respect to the central axis of the antenna 11 is variable, the reflecting plate 12 itself becomes large, and the pressure vessel 10 and the reflecting plate driving device 21 are reduced. Since it is necessary to make it large, it is not preferable.

FIG. 5 shows an embodiment of the present invention , in which the pressure vessel 10 is partitioned by a microwave transmitting member 31 into a reflector housing portion 32 having an opening 13 on the bottom surface and an antenna housing portion 33. The antenna 11 and the reflection plate 12 are arranged to face each other via the microwave transmission member 31, and the microwave radiated from the antenna 11 reaches the reflection plate 12 via the microwave transmission member 31. In this case, the antenna housing portion 33 does not have the opening 13 leading to the furnace, and the antenna 11 can be sufficiently protected from the environment inside the furnace. As the microwave transmitting member 31, for example, a ceramic plate is used. The microwave transmitting member 31 is provided slightly larger than the entire partition wall or the size of the antenna 11. Other configurations are the same as those of the above-described embodiment. In this case, since the gas or the like inside the blast furnace 2 does not enter the waveguide 17, the shutoff valve 19 is not necessarily installed.

  FIG. 6 shows a further different embodiment in which the antenna 11 is arranged outside the pressure vessel 10. The pressure vessel 10 has an opening 13 on the bottom surface, and one side wall is formed of a microwave transmitting member. Only the reflecting plate 12 and the end 22a on the reflecting plate side of the drive shaft 22 are accommodated in the pressure vessel 10, and the antenna 11 is not affected by the inside of the furnace. As in FIG. 5, the antenna 11 and the reflection plate 12 are disposed to face each other via the microwave transmission member 31, and the microwave radiated from the antenna 11 reaches the reflection plate 12 via the microwave transmission member 31. To do. The microwave transmitting member 31 is provided in the same size as the entire side wall of the pressure vessel 10 or the size of the antenna 11. Other configurations are the same as those of the above-described embodiment.

  The example of the procedure which measures the profile of a blast furnace interior entrance using the above profile measuring apparatuses is demonstrated. Note that the measurement procedure described below is an example, and the present invention is not limited to the following measurement method.

  First, the direction of the reflecting plate 12 is fixed to an initial position, for example, directly below, and a microwave is transmitted from the microwave transmitter 18. The microwave is reflected by the reflecting plate 12 via the waveguide 17 and the antenna 11 and irradiated to the blast furnace interior entrance 4 immediately below, and the distance to the blast furnace interior entrance 4 is measured. The distance data is measured at a predetermined time interval such as 1 second, and the descent speed of the blast furnace interior entry 4 is calculated in the data processing unit 20.

  Next, the profile measurement of the blast furnace interior entrance 4 is started. The reflector 12 is rotated by the reflector driving device 21 from the initial position of the reflector 12 to a predetermined position set in advance. The distance to the blast furnace interior entrance 4 is measured for each angle set in advance according to the desired spatial resolution, the distance data is obtained, and the reflector driving device 21 obtains the scanning angle data at that time as a data processing unit. 20 (outward path measurement). Thereafter, similarly to the forward measurement, the microwave scans from a predetermined position to an initial position, and outputs scanning angle data and distance data to the data processing unit 20 (return measurement). The data processing unit 20 averages the distance data at the same scanning angle by the forward path measurement and the backward path measurement based on the input scanning angle data and the distance data at that time, so that the blast furnace interior entry 4 being measured. Calculate the profile of the blast furnace interior entry 4 excluding the effects of descent.

  When the scan angle range is narrow and a series of measurements are completed in a short time, a profile with sufficient accuracy can be obtained with only the forward measurement data. Further, assuming that the blast furnace interior is symmetrical from the center, the entire profile can be predicted using only measurement data in the vicinity of the profile measuring apparatus 1 and in a predetermined range of the facing portion, for example.

  Moreover, you may install the profile measuring apparatus 1 of this invention in two places symmetrically with respect to the central axis of the blast furnace 2. As shown in FIG. In this case, for example, if the profiles on the sides facing each other are measured, the incident angle of the microwave is increased, so that the intensity of the reflected wave is increased and the measurement accuracy is further increased.

  As mentioned above, although preferred embodiment of this invention was described, this invention is not limited to this example. It is obvious for those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea described in the claims. It is understood that it belongs to.

  As shown in FIG. 1, the profile measurement of the blast furnace interior was performed using the profile measuring apparatus 1 of the present invention, and the result of FIG. 7 was obtained. It has been found that measurement results with sufficient accuracy can be obtained by the present invention.

  The present invention can be applied to a profile measuring device that measures a profile in a furnace where high heat, gas, or the like is generated.

DESCRIPTION OF SYMBOLS 1 Profile measuring apparatus 2 Blast furnace 3 Furnace body 4 Blast furnace interior entrance 5 Bellless type charging device 6 Distribution chute 10 Pressure-resistant container 11 Antenna 12 Reflector 13 Opening part 14 Heat-resistant board 15 Gate valve 16 Gate valve drive part 17 Waveguide 17a 22a End 18 Microwave transmitter 19 Shut-off valve 20 Data processing unit 21 Reflector driving device 22 Drive shaft 31 Microwave transmitting member 32 Reflector accommodating part 33 Antenna accommodating part

Claims (5)

A profile measuring device that is installed at the top of the blast furnace and measures the profile of the blast furnace interior,
A microwave transmitter,
An antenna that radiates microwaves;
A waveguide connecting the microwave transmitter and the antenna;
A reflector that reflects microwaves;
A reflector driving device;
A drive shaft for connecting the reflector and the reflector driving device;
The antenna, the end of the waveguide on the antenna side, the reflector, and the end of the drive shaft on the reflector side are installed at the top of the blast furnace and directed toward the furnace of the blast furnace Stored in a pressure vessel having
The microwave transmitter and the reflector driving device are arranged outside the pressure vessel ,
In the pressure vessel, the reflector housing portion and the antenna housing portion having the opening are partitioned by a microwave transmitting member,
The apparatus for measuring a profile of a blast furnace charge, wherein the antenna is disposed in the antenna housing portion so as to face the microwave transmitting member . A profile measuring device that is installed at the top of the blast furnace and measures the profile of the blast furnace interior,
A microwave transmitter,
An antenna that radiates microwaves;
A waveguide connecting the microwave transmitter and the antenna;
A reflector that reflects microwaves;
A reflector driving device;
A drive shaft for connecting the reflector and the reflector driving device;
The reflecting plate and the end of the driving shaft on the reflecting plate side are housed in a pressure vessel having an opening portion that is installed at the top of the blast furnace and facing the furnace.
The antenna, the waveguide, the microwave transmitter, and the reflector driving device are disposed outside the pressure vessel,
The apparatus for measuring a profile of a blast furnace charge , wherein one side wall of the pressure vessel is formed of a microwave transmitting member, and the antenna is disposed to face the microwave transmitting member . The antenna and the drive shaft are arranged so that their center axes coincide with each other,
The reflector is fixed to the drive shaft so as to be at an angle of 45 ° with respect to the central axis of the antenna when viewed from the side of the antenna,
The microwave radiated from the antenna is reflected by the reflector, and reflected by rotating the drive shaft by the reflector driving device so as to scan in the diameter direction passing through the central axis of the blast furnace on the surface of the blast furnace interior entrance. The apparatus for measuring a profile of a blast furnace charge according to claim 1, wherein the plate is operated . The blast furnace installation according to any one of claims 1 to 3 , wherein an opening of the pressure vessel is covered with a heat-resistant board having air permeability, and nitrogen is blown into the pressure vessel from the outside of the blast furnace. Equipment profile measuring equipment. The apparatus for measuring a profile of a blast furnace charge according to any one of claims 1 to 4 , wherein the antenna is a parabolic antenna .

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