JP2007084856A - Method for removing remained pig iron in blast furnace - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for removing remained pig iron with which in the case of performing the repair of a blast furnace, the remained and solidified pig iron in the furnace bottom can safely be removed in a short term by using a wire saw. <P>SOLUTION: In the method for removing the remained pig iron, with which the solidified pig iron 1 remained in the furnace bottom is pulled out to out of the furnace and removed as a divided remained pig iron block 1a, when the repair of the blast furnace is performed; an iron shell at the position for pulling out the divided remained pig iron block, is removed and a penetrating hole under the remained pig iron, is bored in order to insert the wire saw 6 into a furnace bottom refractory under the remained pig iron. Then, the wire saw is inserted through the penetrating hole under the remained pig iron, and wound on the outer periphery of the remained pig iron, and the remained pig iron and the furnace bottom refractory 2 are cut off in the perpendicular direction by using the wire saw and divided into a plurality of remained pig iron blocks and the remained pig iron block is pulled out to out of the furnace. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for removing residues that can be removed in a short period of time and safely after the blast furnace is refurbished.

  When refurbishing the blast furnace, the contents are cooled and solidified by pouring water into the furnace contents that are in a high-temperature molten state. This solidified content remains at the bottom of the furnace. Residue with high specific gravity remains in the furnace bottom and is integrated, and its weight ranges from 300 to 2000 tons. The removal of the residue remaining at the bottom of the furnace is an indispensable process for dismantling the blast furnace body, and becomes a critical path when the blast furnace is repaired. There have been many cases in which the removal of the ruins did not proceed as planned and caused a delay in the repair period, which is a very difficult task.

  Since the residue has a high specific gravity and high hardness, it has been considered that crushing means by blasting is the most suitable method for breaking up in a short period of time. Yes. Therefore, the technology developed by the residue removal method in the blast furnace renovation is a means for efficiently crushing and removing the residue by blasting, and the technology related thereto and mechanization thereof (see Patent Document 1).

  FIG. 6a is an image diagram of a conventional method for removing residues by blasting, and FIG. 6b is a plan view showing an example of a residue split by blasting. A refractory brick is lined on the inner peripheral surface of the iron skin 4 surrounding the outer periphery of the blast furnace, and the refractory brick 2 is formed by laminating the refractory brick on the furnace bottom.

At the time of blast furnace renovation, in order to remove the residue 1 solidified by cooling, two openings are formed in the facing direction of the iron core at the bottom of the furnace to form an iron core opening 5 having a height of about 4 m and a width of about 4 m. Then, the residue 1 is exposed. A blasting hole is drilled in the exposed residue 1 with a drill of the residue punch 15. The depth of the blasting hole is about 1.5 m. The explosive is loaded into this blasting hole, blasted and subdivided. The small residue 1 is carried out by scraping it using a heavy machine 16 such as a bulldozer excavator. As a result of the above operations, the process proceeds sequentially from the opening position of the iron shell on the outer periphery of the residue to the center of the furnace, and the subdivision is repeated in order from the number (1) shown in FIG.
JP 2000-256717 A

  However, the removal work of the residue by the conventional blasting is about 1.5m from the outer periphery of the residue due to the demolition of the residue by one blasting, and in order to reach the center of the residue The blast must be carried out a number of times depending on the distance to the center of the ruins. Further, since the area of the cutting face becomes wider as it goes in the direction of the core, in order to dig a distance of 1.5 m over the entire cutting face, a large number of holes for blasting and the number of times of blasting are required. For this reason, although it depends on the amount of residue, it takes a very long time to complete the removal of the residue, and in the past results, when removing 300 tons of residue by blasting, It took 7 days, and about 1500 tons, it took about 14 days.

  Moreover, since the method of removing the residue by blasting involves danger, thorough safety measures are required. In addition, when crushing the residue by blasting, the peripheral equipment was damaged due to the blast at the time of the blasting and the scattering of the small pieces of the residue, so it was necessary to repair the damaged equipment. In order to prevent damage to the peripheral equipment, a large portion of the iron opening for carrying out the small residue is invested in safety measures such as setting up temporary equipment to prevent scattering.

  Normally, mantels to be removed are placed around the remnants and used as protective walls to prevent scattering. However, when diverting mantels, it is necessary to provide protective walls to prevent mantel damage caused by blasting. He spent a curing cost.

  Also, in order to ensure the safety of surrounding workers due to the blasting work, the blasting work time zone was forced to temporarily lose the surrounding work, such as temporarily suspending the surrounding work and evacuating the worker. For example, the evacuation start of the worker of the peripheral work by the blasting work starts about one hour before the blasting execution and is about two hours until it is confirmed that the explosives are not confirmed after the blasting is completed. For example, when performing blasting 20 times, evacuation is repeated for each blasting, so the loss time of the peripheral work is about 40 hours.

  Then, this invention provides the removal method of the residue which can remove the solidified residue which remain | survives in a furnace bottom using a wire saw in a short period of time safely when repairing a blast furnace. It is.

  The residue removal method of the present invention was divided in the residue removal method in which the solidified residue remaining in the bottom of the furnace was pulled out of the furnace as a divided residue block and removed when the blast furnace was repaired. Remove the iron skin from the part where the residue block is pulled out, drill a bottom through-hole for inserting the wire saw into the bottom refractory under the residue, insert the wire saw through the bottom bottom through-hole, Is wrapped around the outer periphery of the residue, a wire saw is run, the residue and the bottom refractory are cut vertically, divided into a plurality of residue blocks, and the residue block is pulled out of the furnace To do.

  Residue cutting can be performed by cutting the residue and the bottom refractory in a vertical direction along a dividing line parallel to the pulling direction of the remaining block or a dividing line extending in the pulling direction to divide the block into a plurality of blocks. Alternatively, the bottom bottom through-hole through which the wire saw is inserted is drilled in a direction perpendicular to the direction in which the residue block is drawn, and the residue and the furnace bottom fireproof along the dividing line in the direction perpendicular to the direction in which the residue block is drawn. The object can be cut vertically and divided into two remnant blocks. Moreover, you may cut | disconnect arbitrary some dividing lines in parallel with a some wire saw. Furthermore, when cutting a residue, you may cut | disconnect, cooling a wire saw by supplying a cooling fluid continuously to the path | route which a wire saw travels.

  Also, when pulling out the residue block outside the furnace, install it next to the residue block by aligning the top level of the residue block carry-out carriage or residue block carry-out stand with the same level as the bottom of the residue block to be drawn out. Then, a horizontal force is applied to the residue block to cause slippage between the residue block and the remaining furnace bottom refractory, and the residue block is moved horizontally in the horizontal direction and pulled out to draw out the residue block carriage or residue. A mobile device for loading the residue block into the space formed between the residue block and the remaining refractory at the bottom of the furnace is loaded by loading the residue block on a stand for carrying out or jacking up the residue block. It may be arranged at the lower part of the block, the residue block may be jacked down and loaded on the moving device, and the moving device loaded with the residue block may be moved horizontally to draw the residue block out of the furnace.

  The residue removal method of the present invention uses a wire saw to cut the residue into a large residue block, and pulls the residue block out of the furnace, thereby removing the residue that has been broken by conventional blasting. Compared with the removal method, the residue can be removed reliably in a short period of time.

  In addition, the gap between the residue cutting portions by the wire saw is about 10 mm, and the clearance between the residue blocks after cutting is narrow, but the cut surface is smooth, and even when pulling out the residues between the blocks, between adjacent blocks Since there is no catch due to the unevenness, and the cut surface slips even when contacting between the blocks, the residual block can be easily pulled out. For this reason, it is possible to remove a residual block having a large division at a time. In addition, by taking the width of the remaining block in the pull-out direction so that the dividing line is widened, a cutting allowance is formed, and there is no contact with the adjacent remaining block, and smooth pull-out can be performed.

  In addition, since the method for removing residue according to the present invention cuts the entire cross section of the residue with a wire saw, it is necessary to consider the removal depth of the residue that affects the management of the process progress when subdividing by blasting Because there is no, management of removal work is easy.

    The method of removing the residue using the wire saw of the present invention is safe because there is no blast and scattering of the small pieces of residue because blasting is not performed, and furthermore, temporary costs such as installing a protective wall against these are reduced. The economic effect is also extremely large.

  In the present invention, it becomes possible to cut the high-temperature residue that has just been cooled and solidified by continuously supplying a cooling fluid to the path where the wire saw travels and cooling the wire saw. It can be shortened.

  In the removal method of the present invention, by preparing a plurality of wire saw machines regardless of the number of residues divided, it is possible to cut many faces at once, so the time to cut any plurality of faces is Efficient dismantling is possible almost unchanged.

  When the residue block is pulled out of the furnace, it is placed next to the unloading carriage or the unloading stand residue block of the residue block and loaded with the residue block, or the residue block is jacked up and left in the mobile device. By loading the soot block and pulling it out of the furnace, the residue block can be easily carried out.

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

  The residue removal method according to the present embodiment is an example in which a residue block obtained by cutting the residue with a wire saw and dividing it into a plurality of pieces is pulled out of the furnace.

  FIG. 1a is a plan view showing an example of a state in which the iron skin has been removed and a parting line of the residue, FIG. 1b is a schematic view showing a state in which a through hole is drilled in the bottom refractory, and FIG. 1c is a wire saw. The schematic which shows the state which has cut | disconnected, FIG. 2 is the schematic of a wire saw.

  At the time of refurbishing the blast furnace, the residue 1 cooled and solidified by pouring water remains on the furnace bottom refractory 2 made of a stacked structure such as carbon brick. The slag 3 remaining on the surface of the residue 1 is also cooled and solidified.

  The process of the removal method of a present Example is demonstrated.

(1) Removal of the iron skin The iron skin 4 at the position of the residue 1 at the lower part of the furnace body and the opposite position is removed to provide the iron skin opening 5. One iron skin opening 5 serves as an operation side of the wire saw machine 7 through which the wire saw 6 enters and exits. The other opening 5 is on the drawing side (arrow) of the divided residue block 1a and is opened to a size that allows the residue block 1a to be drawn.

(2) Perforation of the bottom bottom through-hole As shown in FIG. 1b, since the wire saw 6 needs to be passed through the bottom of the bottom 1 in order to wind the wire saw 6 around the bottom 1, the furnace under the bottom 1 A bottom bottom through-hole 8 is formed by a boring machine 9 at an arbitrary level of the bottom refractory 2. For example, when the outer diameter of the wire saw is about 11 mm, the residual bottom through-hole 8 is set to about 65 mm so that the wire saw 6 can travel without difficulty.

(3) Cutting with a wire saw The wire saw 6 is widely known. As shown in FIG. 2, a bead 6a made of an abrasive layer such as a base metal and a diamond bead is spaced from a wire rope that is a metal stranded wire. The wire rope is covered with resin or rubber 6b between the beads. In the present invention, for example, “Allied Material Product No. EWLS-255” used for dismantling and repairing subways, buildings, roads, bridges and the like can be used as the wire saw.

  From the viewpoint of preventing clogging of the diamond beads 6 a of the wire saw 6, it is preferable that the bottom bottom through-hole 8 cuts as many furnace bottom refractories 2 as possible simultaneously with the residue 1. It is better to drill at a level close to the bottom plate at the bottom of the furnace. When only the metal is cut with the wire saw 6, the metal adheres to the diamond beads 6 a of the wire saw 6, causing clogging between the beads connected to the wire, and cutting becomes difficult. However, by cutting the furnace bottom refractory 2 at the same time, good cutting is possible without causing clogging. This is because the chips of the furnace refractory 2 have no adhesion or stickiness to the diamond beads 6a, and the non-adhesive chips are present, so that the chips of the residue 1 become diamond beads. It is considered that the diamond beads 6a always maintain the function of the blade without adhering to the surface.

  The tip of the wire saw 6 of the wire machine 7 is inserted into the bottom bottom through-hole 8 drilled in the furnace bottom refractory 2 and is further wound around the bottom 1 to be wound around the bottom 1. When the traveling speed of the wire saw 6 is less than 20 m / second, efficient cutting becomes difficult, and when the wire saw 6 exceeds 30 m / second, the wire saw 6 is frequently cut. Therefore, a range of 20 m / second to 30 m / second is preferable.

  As shown in FIG. 1a, the residue 1 cut by the wire saw 6 is divided in a vertical direction along a dividing line 10 parallel to the drawing direction or a dividing line 11 spreading toward the end in the drawing direction. And is divided into two or more residual blocks 1a.

(4) Pulling out residue block As shown in FIGS. 1d and 1e, the divided residue block 1a is provided with a through-hole 1b in the vertical direction by core boring, as shown in FIGS. 1d and 1e. And is pulled out by the hydraulic jack 12a through the wire 12b. The furnace refractory 2 is separated or collapsed by a large pulling force during pulling.

  When the residue block is pulled out of the furnace, it is installed next to the residue block with the same level as the bottom surface of the residue block to be pulled out and the top surface level of the unloading carriage, and horizontal force is applied to the residue block. To create a slip between the residue on the bottom refractory and the bottom refractory, horizontally move the residue block, pull it out, and load it on the unloading cart or unloading platform. To do.

Table 1 compares the removal period of the wire saw removal method according to the present invention and the conventional method of breaking and removing by blasting. The removal method using the wire saw according to the present invention is an example in which the residue amount is 300 tons and the residue amount is 1500 tons and the residue amount is 1500 tons.

  From Table 1, the removal method according to the present invention significantly shortened the removal period compared to the conventional removal method.

  In this embodiment, the residue is divided into two parts and removed. FIG. 3A is a plan view showing the dividing line and the drawing direction of the residue in this embodiment, and FIG. 3B is the dividing line and the drawing line of the residue in another embodiment. It is a top view which shows a direction.

  An iron skin opening 5 is provided on the side from which the iron skin 4 at the position of the residue 1 is removed and the residue is drawn out. The iron skin opening 5 opens to a size that allows the two-part residue block 1a to be pulled out.

  The dividing line 10 of the residue 1 cut by the wire saw is formed in a diametrical direction perpendicular to the pulling direction when seen in a plan view, and the residue 1 is cut in the vertical direction along the dividing line and divided into two.

  A residual bottom through hole 8 through which the lower wire saw of the residual residue 1 is passed through an arbitrary level of the furnace bottom refractory 2 is formed in a diameter direction perpendicular to the pulling direction.

  Insert the tip of the wire saw through the bottom bottom through-hole 8 drilled in the furnace bottom refractory 2, turn the top of the wire saw 1 and wind it around the residue 1, then cut the residue with a wire saw, The divided residue block 1a is pulled out of the blast furnace in the direction of the arrow by hanging a wire rope.

  In addition, as shown in FIG. 3b, when all the iron shells around the residue 1 are removed, the residue block 1a can be pulled out in an arbitrary direction indicated by an arrow.

  In the present embodiment, the residue 1 is extracted by dividing it into two, which is effective when the amount of residue is relatively small.

  FIG. 4A is a front view showing an example of the drawer of the divided residual block, and FIG. 4B is a plan view.

  After dividing the residue with a wire saw, jack up the residue block 1a to be pulled out, extend the drawer frame 12 under the residue block 1a, and move the slide plate 13 over the drawer frame 12 to leave the residue block 1a. After that, the residue block 1 a is placed on the slide plate 13. Next, the slide plate 13 on which the residue block 1a is placed is pulled out and slid on the gantry 12 in the pulling direction by the hydraulic jack 12a. In addition, it can replace with the slide plate 13 and can use other moving apparatuses, such as a trolley | bogie.

  In this embodiment, the divided residue block can be pulled out with less force compared to separating and breaking the bottom refractory and moving it over the bottom refractory and dragging it out.

  By cutting the wire saw when cutting with a wire saw, it is possible to cut the residue having a high temperature. The heat capacity of the residue cooled and solidified by water injection in the furnace is large, and the residue temperature is still high even after several days. For example, the temperature of the residue itself is normally 600 ° C. or higher even after 7 days have passed since the completion of the water injection cooling. On the other hand, the rubber or resin part of the wire saw generally has a heat-resistant temperature of 200 ° C. or less, and does not have the heat resistance necessary for cutting high temperature residue, so it is difficult to cut the residue as it is. is there.

  Therefore, in order to cut the high-temperature residue while securing the wire strength, the cutting surface where the wire comes into contact with the high-temperature residue, and the range in which the wire passes through the high-temperature part, such as cooling water or cooling nitrogen By cutting the residue while removing heat by continuously supplying the cooling fluid, the residue can be cut by a wire saw.

  As shown in FIG. 5, the cooling fluid supplied can be used efficiently by closing the cut end with mortar 14 after the start of cutting.

It is a top view which shows an example of the state which removed the iron skin, and the dividing line of a residue. It is the schematic which shows the state which drills a through-hole in a furnace bottom refractory brick. It is the schematic which shows the state which is cutting the residue with a wire saw It is the schematic which shows an example of drawer | drawer. It is the schematic which shows an example of drawer | drawer. It is the schematic of a wire saw. It is a top view which shows the parting line and extraction direction of the residue of a present Example. It is a top view which shows the dividing line of the residue of another Example, and the drawing-out direction. It is a front view which shows the example of drawer | drawing-out of the divided residue block. It is a top view which shows the example of drawer | drawing-out of the divided residue block. It is the schematic which shows the state which closed the cutting | disconnection edge part with the mortar. It is an image figure of the residue removal work by the conventional blasting. It is a top view which shows an example of the residue subdivision by blasting.

Explanation of symbols

1: Residue 1a: Residual block 1b: Through-hole 2: Furnace bottom refractory 3: Slag 4: Iron skin 5: Iron skin opening 6: Wire saw 6a: Bead 6b: Resin and rubber 7: Wire saw machine 8 : Remaining bottom through-hole 9: Boring machine 10, 11: Dividing line 12: Drawer base 12a: Hydraulic jack 12b: Wire 13: Slide plate 14: Mortar 15: Remnant punch 16: Heavy machinery

Claims (7)

When renovating the blast furnace, in the method of removing the residue, the solidified residue remaining at the bottom of the furnace is pulled out of the furnace as a divided residue block and removed.
Remove the iron skin of the part that pulls out the divided residue block,
Drill a bottom bottom through-hole to insert a wire saw into the bottom refractory bottom
Insert a wire saw into the bottom bottom through-hole, wind this wire saw around the outer periphery of the residue,
Run the wire saw and cut the residue and furnace bottom refractory vertically to divide it into multiple residue blocks,
A method for removing a residue, wherein the residue block is pulled out of the furnace.   The residue and the bottom refractory are cut in a vertical direction and divided into a plurality of blocks along a dividing line parallel to the drawing direction of the residue block or a dividing line extending in the drawing direction. 1. A method for removing residues as described in 1.   3. The method for removing a residue according to claim 2, wherein any plurality of dividing lines are cut in parallel with a plurality of wire saws. Perforate bottom through-holes through which wire saws are inserted are drilled in a direction perpendicular to the pull-out direction of the residue block,
2. The residue according to claim 1, wherein the residue and the furnace bottom refractory are cut in a vertical direction along a dividing line in a direction perpendicular to the direction in which the residue block is drawn, and divided into two residue blocks. Removal method.   The residue according to any one of claims 1 to 4, wherein when cutting the residue, the cooling fluid is continuously supplied to a path along which the wire saw travels to cut the wire saw while cooling the wire saw. Removal method. When pulling out the residue block outside the furnace, install it next to the residue block by aligning the top level of the carriage for removing the residue block or the carriage for removing the residue block with the same level as the bottom surface of the residue block to be drawn out,
A horizontal force is applied to the residue block to cause slippage between the residue block and the remaining furnace bottom refractory, and the residue block is moved horizontally in the horizontal direction and pulled out to draw out the residue block or residue block. The residue removal method according to any one of claims 1 to 5, wherein the residue is loaded on a carry-out stand. When pulling out the residue block outside the furnace,
Jack up the remaining block,
A moving device for loading the residue block in a space formed between the residue block and the remaining furnace bottom refractory is disposed at the bottom of the residue block,
Jack down the remaining block and load it on the moving device.
The method for removing a residue according to any one of claims 1 to 5, wherein the moving device loaded with the residue block is horizontally moved to draw the residue block out of the furnace.

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