JP6533938B2 - Method of detecting dust adhesion state in surface detection device of charge in blast furnace - Google Patents

Description

  The present invention is a surface detection apparatus of the type that transmits a detection wave to the inside of the blast furnace by reflecting means while transmitting the detection wave to the propagation part installed outside the blast furnace, to the parts present inside the propagation part Relates to a method of detecting the adhesion state of

  In the blast furnace, it has been carried out to measure the deposition amount of the charge such as coke and iron ore, or to measure the surface profile to optimize the deposit state of the charge. As described in, for example, Patent Document 1, as such a surface detection device, a lance having a reflecting plate at its tip is inserted into a furnace, and detection waves are transmitted / received while horizontally moving the lance. Surface detectors have been used that scan the surface of the receptacle to detect the surface profile.

  However, in the surface detection apparatus provided with the lance, a large space is required outside the furnace to move the lance, and the high temperature in the furnace causes the lance to be bent and causes problems such as horizontal movement of the lance. is there. Therefore, in the surface detection device described in Patent Document 2, a pressure-resistant container is attached immediately above the opening provided in the vicinity of the furnace top of the blast furnace, and an antenna directly connected to the reflection means and the transmission / reception means is accommodated in the container to transmit and receive The detected wave from the means is reflected by the reflecting means and sent through the opening to the inside of the blast furnace, and the detected wave reflected by the charge in the furnace is again reflected by the reflecting means and sent to the transmitting and receiving means, The surface of the charge is scanned to measure the surface profile by changing the reflection angle of the means.

  In addition, the applicant also previously attached a pipe continuously in the vicinity of the opening provided in the vicinity of the furnace top of the blast furnace in Patent Document 3, and installed a reflection means at the end of the pipe opposite the opening. An antenna directly connected to the transmitting and receiving means is installed at the other end, the detected wave from the transmitting and receiving means is reflected by the reflecting means and sent through the opening to the inside of the blast furnace, and the detected wave reflected from the charge in the furnace The light is again reflected by the reflecting means and sent to the transmitting / receiving means, and the surface of the charge is scanned to measure the surface profile by changing the reflection angle of the reflecting means.

Japanese Patent Application Publication No. 2002-115008 JP, 2011-145237, A JP, 2014-19699, A

  Since iron ore fragments, coke fragments, dust and the like enter from the inside of the furnace from the blast furnace through the opening, in Patent Document 2, the air-permeable heat-resistant material made of a material transmitting the detection wave between the opening and the reflection means While being blocked with a board, an inert gas is supplied into the pressure-resistant container to blow out from the vent holes of the breathable heat-resistant board. Further, in Patent Document 3, in the inside of the tubular body, between the reflection means and the antenna, in the order from the side closer to the reflection means, a permeable partition made of a heat-resistant material that transmits the detection wave and the detection wave are transmitted. A non-air-permeable partition made of a heat-resistant material is installed, and an inert gas is supplied to the space formed between both the partitions, and the inert gas is blown out from the vent of the permeable partition.

  However, it is not possible to completely prevent the penetration of dust smaller than the air-permeable heat-resistant board or the air-permeable partition's vent into the interior of the pressure container or tube, and the air-permeable heat-resistant board or the air-permeable partition Cause a jam. Further, in Patent Document 2, a partition wall may be provided between the antenna and the reflection means (see FIG. 5 of the official gazette), in which case dust adheres to the partition wall. Also in Patent Document 3, dust adheres to the non-air-permeable partition wall. Clogging is also a phenomenon that occurs as dust adheres to the vent, so in the following description it is also referred to as "adherence" including clogging.

  Since the air-permeable heat-resistant board, the air-permeable partition wall, and the non-air-permeable partition wall are on the propagation path of the detection wave, if the adhesion amount of dust increases, the reception intensity of the detection wave decreases and the detection condition deteriorates. Since the generation of dust changes depending on the type (composition) and size of coke and iron ore, the loading amount, temperature and pressure in the furnace, etc., the amount of dust adhesion necessarily increases in proportion to the operation time of the blast furnace Even if the ventilation heat-resistant board, the air-permeable partition, and the non-air-permeable partition are replaced at the time of regular inspection, the adhesion amount of dust suddenly increases until the next periodic inspection, and transmission and reception can be performed. There is also a possibility that it will disappear. In the past, it was not possible to detect the adhesion of dust during operation of the blast furnace, and even if it was not a regular inspection, transmission and reception could be performed and the operation of the blast furnace had to be stopped, which made the production plan crazy. Will occur.

  In Patent Document 3, a window is provided immediately above the reflecting means of the tube body, and the state of dust adhesion to the reflecting surface is observed by rotating the reflecting means by 180 ° and directing the reflecting surface to the window. It is not possible to numerically detect the adhesion of dust to breathable partition walls or non-breathable partition walls.

  The present invention has been made in view of such a situation, and propagates the detection wave to the propagation part installed outside the blast furnace, and sends the detection wave inside the blast furnace by the reflection means installed inside the propagation part. An object of the present invention is to provide a surface detection apparatus of a type that performs transmission and reception, and easily and accurately detects the adhesion state of dust to a member installed on a propagation path in a propagation unit without disassembling the apparatus.

  In order to solve the above problems, the present invention propagates the detection wave from the transmitting and receiving means to the propagation part connected to the opening of the blast furnace, and sends the detection wave into the furnace through the opening by the reflection means installed in the propagation part. The detection wave reflected on the surface of the charge in the furnace is reflected by the reflection means, propagated to the propagation part and sent to the transmission / reception means, detected by the transmission / reception means, the distance to the surface of the charge, the surface A surface detection apparatus for detecting a profile, comprising: a method of detecting an adhesion state of dust from inside a blast furnace to a component installed on a propagation path of a propagation unit, which is a reflection surface of reflection means when the surface detection apparatus is attached Is rotated in a direction other than the opening of the blast furnace to transmit and receive detection waves to and from the inner wall of the propagation part, measure the initial reception strength, and at predetermined time intervals, the same as when attaching the surface detection device Under the measurement conditions of Measure the reception strength at the time of to determine the attenuation from the initial reception strength, and determine the replacement time and cleaning time of the members on the propagation path based on the time when the attenuation reaches or exceeds the preset threshold. The present invention provides a method of detecting dust adhesion in a surface detection device for a charge in a blast furnace characterized by

  In the dust adhesion state detection method of the present invention, the initial reception intensity measured with the inner wall of the propagation part at the time of attachment of the surface detection device is compared with the reception intensity measured under the same conditions at the time after a predetermined time has elapsed. Do. Then, the attenuation amount from the initial reception intensity of the reception signal is determined, and if it is considerably smaller than the predetermined threshold value, it is judged that the operation of the blast furnace may be continued as it is. Can be reflected in the decision on the replacement time as it is close.

It is principal part sectional drawing which shows an example of the surface detection apparatus of a blast-furnace charge. It is sectional drawing which looked at the connection part of the opening part of a blast furnace, and a pipe body from the side which opposes a reflective surface. It is a figure for demonstrating the transmission / reception method for confirming the adhesion condition of dust. It is principal part sectional drawing which shows the other example of the surface detection apparatus of a blast-furnace charge.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

  The method for detecting the dust adhesion state of the present invention (hereinafter also referred to as "the present detection method") propagates the detection wave to the propagation part connected to the opening of the blast furnace and detects the wave using the reflection means installed in the propagation part The present invention is directed to a surface detection device configured to send in the furnace to transmit and receive the inside of the furnace. As such a surface detection apparatus, the surface detection apparatus described in patent document 3 can be illustrated, for example.

  That is, as shown in FIG. 1, an opening 101 is opened near the top of the blast furnace 100, and the connection portion 32 of the tube 30 of the surface detection device 1 is connected to the opening 101. The reflection means 20 is accommodated in the space 31 directly above the connection portion 32, and the antenna 11 is installed at the other end of the tube 30 so as to face the reflection surface 20 a of the reflection means 20. The antenna 11 is connected to a microwave or millimeter wave (hereinafter collectively referred to as "detected wave") transmitting / receiving means 10 through the waveguide 12. The detected wave transmitted from the antenna 11 is a tube 30. And is reflected by the reflecting surface 20 a of the reflecting means 20 and is sent into the furnace through the opening 101. The tube body 30 corresponds to a propagation portion, and a propagation path is formed which continues from the antenna 11 through the reflection surface 20a and into the furnace.

  Further, in the inside of the tubular body 30, a permeable partition 40 is disposed to face the reflection surface 20a of the reflection means 20, and a non-permeable partition 41 is provided between the permeable partition 40 and the antenna 11. It is arranged. In addition, the permeable partition 40 and the non-permeable partition 41 correspond to the member on a propagation path. Then, an inert gas such as nitrogen gas is supplied at high pressure from the gas supply port 50 to the space partitioned by the both partitions 40 and 41.

  The non-air-permeable partition wall 41 is made of a material that transmits detection waves, is heat resistant, and has mechanical strength that can withstand high pressure inert gas, and can be made of, for example, a ceramic. However, depending on the type of ceramic, some may reflect the detection wave, and may be noise when the antenna 11 is too close or the transmission intensity of the detection wave is low. Therefore, it is preferable to incline the non-air-permeable partition wall 41 with respect to the antenna 11 as illustrated.

  The breathable partition wall 40 may be made of porous ceramic, or may be a breathable fabric made of ceramic fiber, glass fiber, or the like.

  Moreover, the gate valve 110 intervenes in the connection part of the connection part 32 of the pipe body 30, and the opening part 101 of the blast furnace 100, it will be in an open state at the time of measurement, and it will be in a closed state at the time of non-measurement.

  In the surface detection device 1 configured as described above, at the time of measurement, as shown in the figure, the detection wave (Ms) transmitted from the transmitting and receiving means 10 through the antenna 11 is not air permeable partition 41 and air permeable partition 40. The light is reflected by the reflecting surface 20a of the reflecting means 20, passes through the connecting portion 32, and enters the furnace from the opening 101 of the blast furnace 100. Then, the transmission detection wave Ms is reflected by the surface of iron ore and coke (not shown) which are charges accumulated in the furnace, and the reflected wave (Mr) is transmitted to the reflection means 20 through the opening 101. After being reflected by the reflecting surface 20 a, the air is transmitted through the permeable partition 40 and the non-permeable partition 41, received by the antenna 11, and detected by the transmission / reception means 10. Then, the transmitting and receiving means 10 sends a reception signal to a computing device (not shown), and the computing device determines the distance to the charge in the furnace based on the transmission and reception result of the detection wave.

  In addition, the reflecting surface 20a of the reflecting means 20 can be rotated by the motor 70 in the direction perpendicular to the propagation axis of the detection wave. By rotating the reflecting surface 20a, as shown in FIG. 2, a detection wave can be transmitted along the rotating direction, and the surface of the charge in the furnace is linearly scanned to profile the surface Can be detected. As shown in the figure, the connecting portion 32 of the tubular body 30 is formed in a fan-like shape which gradually expands in diameter toward the blast furnace corresponding to the rotation angle θ (swing width) of the reflecting surface 20a. Ensure that the sidewalls do not interfere with transmission and reception.

  Furthermore, a window 80 is formed at an appropriate place around the reflecting means 20 of the tube 30, for example, a portion immediately above the reflecting surface 20a, and the reflecting means 20 is rotated 180 ° to make the reflecting surface 20a face the window 80, It is also possible to observe the adhesion of dust to the reflective surface 20a.

  In the surface detection device 1 described above, high pressure inert gas is supplied from the gas supply port 50 to the space between the breathable partition 40 and the non-breathable partition 41 at the time of measurement, and the flow of the breathable partition 40 is performed. By blowing the air from the pores, adhesion of dust to the surface 41 a of the air-permeable partition 40 and the non-air-permeable partition 41 on the partition 40 side is prevented. However, it is impossible to completely prevent the adhesion of such dust, and in fact, the adhesion amount of dust increases with the operation of the blast furnace.

  Therefore, in the present detection method, as shown in FIG. 3, the reflecting means 20 is turned so that the reflecting surface 20a of the reflecting means 20 faces in a direction different from the opening 101 of the blast furnace 100 when the device is attached. Transmit and receive detection waves at moving positions. By the rotation of the reflecting means 20, the reflecting surface 20a faces the inner wall 30a of the tube 30, and performs transmission and reception with the inner wall 30a. Then, the reception strength at that time is taken as the initial reception strength. The reflecting surface 20a does not have to be at a position of 90 ° with respect to the center of the opening 101 as shown in the drawing, and if it is a position facing the inner wall 30a of the tube 30, the rotation angle of the reflecting means 20 Is unquestionable. For example, the reflecting means 20 may be turned 180 ° so that the reflecting surface 20a faces the inner wall 30a facing the opening 101 (the ceiling portion of the inner wall 30a in FIG. 3). When the window 80 is formed, when the reflection means 20 is rotated 180 °, the reflection surface 20a faces the window 80 and transmission and reception can not be performed. Therefore, the rotation angle is set between the window 80 and the inner wall 30a other than the window 80. adjust.

  Thereafter, while the blast furnace is operated, transmission and reception are performed between the inner wall 30a of the tubular body 30 at predetermined time intervals under the same measurement conditions as at the installation of the apparatus, that is, the output of the detection wave and the rotation angle of the reflection means 20 are the same. The reception strength at each measurement time is measured, and the attenuation from the initial reception strength is determined. In this transmission and reception, since the detection wave transmits only the non-air permeable partition 41 and the air permeable partition 40, the reception intensity is attenuated according to the amount of dust attached to both the partitions 41 and 40 and the reflective surface 20a.

  When the amount of dust attached to the permeable partition 40, the non-permeable partition 41, and the reflective surface 20a is large when the attenuation amount becomes equal to or greater than the preset threshold, the replacement time and the cleaning time are near. Judge, reflect on the decision of replacement time and cleaning time. The threshold value is determined in consideration of the safety factor, but it is appropriate that the reception intensity is about 70% (30% in attenuation ratio) of the initial reception intensity.

  In addition, a surface detection apparatus having a configuration as shown in FIG. 4 is also known. The surface detection apparatus shown in FIG. 4 corresponds to FIG. 5 of Patent Document 2. In the illustrated surface detection apparatus, a pressure resistant container 120 is installed at the opening 101 of the blast furnace 100 via the gate valve 110, and the reflecting means 20 and the antenna 11 are disposed to face each other inside the pressure resistant container 120. The antenna 11 and the reflection means 20 are partitioned by a partition wall 122 made of a material that transmits the detection wave. The transmitting and receiving means 10 is connected to the antenna 11 via the waveguide 12 to the outside of the pressure resistant container 120, and the reflecting means 20 is rotated by the motor 70. The detection wave from the transmission / reception means 10 is transmitted from the antenna 11, reflected by the reflection means 20, transmitted through the opening 101 to the inside of the blast furnace 100 (Ms), and reflected by the charge (Mr) Are reflected by the reflecting means 20, received by the antenna 11, and detected by the transmitting / receiving means 10. At that time, by rotating the reflecting means 20 by the motor 70, the detection wave Ms is swung in the back and forth direction of the paper surface to scan the surface of the charge. In this surface surface projecting apparatus, since the detection wave propagates inside the pressure resistant container 120, the pressure resistant container 120 corresponds to a propagation portion.

  In addition, an inert gas is supplied from the gas supply port 50 to the housing portion 123 of the reflection means 20 of the pressure container 120, and the inert gas is ejected from the air-permeable heat resistant board 121 to infiltrate dust into the pressure container 120. I'm preventing. However, the clogging of the air-permeable heat-resistant board 121 and the invading dust can not be completely prevented from adhering to the reflection means side surface 122 a of the partition wall 122, and the reception intensity of the detection wave is reduced.

  Therefore, as described above, the reflection means 20 is rotated to transmit and receive detection waves in a state where the reflection surface 20a is directed to a surface (a side surface or a ceiling surface) of the blast furnace 100 other than the opening 101 of the blast furnace 100. And compared with the receiving intensity at the time of device attachment, the adhesion situation of dust on the reflecting means side surface 122a of the air-permeable heat resistant board 121 and the partition wall 122 is inferred from the attenuation amount.

  As described above, surface detection of a method of transmitting the detection wave to the inside of the furnace by the reflection means 20 while transmitting the detection wave to the propagation part (the tube 30 and the pressure container 120) installed outside the furnace of the blast furnace 100. In the case of the device 1, the non-air flow arranged in the propagation path of the detection wave by the simple operation of performing transmission and reception with the inner wall of the propagation portion other than the opening 101 of the blast furnace 100 at the time of installation and at predetermined time intervals. It is possible to accurately detect the adhesion of dust to members such as the elastic partition 41, the permeable partition 40, the reflective surface 20a, the permeable heat resistant board 121, and the partition 122 without disassembling the apparatus.

  Although the above-mentioned surface detection device is configured to rotate the reflection surface in one direction to scan the detection wave linearly in the surface of the charge, the reflection surface is rotated in two directions to detect the detection wave. Also in the surface detection device configured to scan the surface of the insert in a planar manner, similarly, only by transmitting and receiving to and from the inner wall of the propagation path other than the opening of the blast furnace, Can accurately detect the adhesion of dust on

  The present invention can also be applied to a surface detection apparatus in which the reflection surface is also rotated in the same direction by connecting the antenna and the reflection plate and rotating the antenna around the propagation axis of the detection wave. Even in such a surface detection device, the surface detection device is installed outside the blast furnace, and the air-permeable heat-resistant board is installed at the opening of the blast furnace. Also, a cylindrical member is attached to the antenna, and a reflecting plate is fixed to a part of the tip, and the opening of the cylindrical member is closed with a permeable partition or a non-permeable partition. Therefore, dust adheres to the air-permeable heat-resistant board and both partition walls, so that the antenna can be directed to directions other than the opening in the same manner as described above, and the adhesion state can be determined from the reception intensity.

Reference Signs List 1 detection device 10 transmitting / receiving means 11 antenna 12 waveguide 20 reflecting means 30 tube 40 air-permeable partition wall 41 non-air-permeable partition wall 70 motor 100 blast furnace 101 opening 120 pressure-resistant container 121 air-permeable heat resistant board 122 partition wall

Claims (1)

The detection wave from the transmitting and receiving means is propagated to the propagation part connected to the opening of the blast furnace, and the detection wave is sent into the furnace through the opening by the reflection means installed in the propagation part and reflected on the surface of the load in the furnace. Of the detected wave is reflected by the reflection means to propagate the propagation part and sent to the transmission / reception means, and the propagation part in the surface detection device for detecting the distance to the surface of the charge and the surface profile detected by the transmission / reception means A method of detecting the adhesion of dust from inside the blast furnace to components installed on the propagation path of
At the time of attachment of the surface detection device, the reflection surface of the reflection means is turned toward the direction other than the opening of the blast furnace to transmit and receive detection waves with the inner wall of the propagation part, and measure the initial reception intensity.
At predetermined time intervals, measure the reception intensity at each time under the same measurement conditions as when attaching the surface detection device to determine the attenuation from the initial reception intensity,
A method of detecting dust adhesion in a surface detection device for in-blast furnace charge characterized by determining replacement time and cleaning time of members on the propagation path based on the time when the attenuation amount becomes equal to or more than a preset threshold value. .

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