JP2008215850A - Extraction pretreatment device of solidified melt - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pretreatment device capable of readily extracting a receptor from a mold, by surely removing a solidified material adhering to a cavity of a slag layer upper layer, a receptor flange part, or the upper surface and the upper part inner surface of the mold. <P>SOLUTION: This extraction pretreatment device of a solidified melt is formed, by combining a slag knocker 1 for flattening the slag layer by an excitation force; a mold upper surface knocker 2 for exfoliating the solidified material adhering to the mold upper surface; a mold inner surface impact cleaner 3 for crushing, exfoliating and removing the solidified material, adhering to the mold upper part inner surface, the receptor flange surface and a shell part inner surface by applying mechanical impact, after being moved on the trace of the mold upper part inner surface, the receptor flange surface and the shell part inner surface; a mold upper surface cleaner 4, comprising a motor-driven rotation brush for removing the solidified material exfoliated by the mold upper surface knocker 2; and a receptor upper surface cleaner 5, comprising a motor-driven rotation brush for removing the solidified material on the receptor upper surface crushed by the mold inner surface impact cleaner 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  In the present invention, when a high-temperature melt discharged from a melting furnace is introduced into a mold (mold) and solidified by cooling (hereinafter referred to as “melt-solidified body”), the solidified body is extracted from the mold. The present invention relates to a pretreatment device.

  Incineration and melting treatment is performed as a final treatment method (volume reduction treatment) of waste containing various inorganic substances, metals and organic substances, for example, radioactive miscellaneous solid waste generated from nuclear power plants. Various types of incineration and melting treatment apparatuses for radioactive miscellaneous solid waste for such purposes are known. In any of the processing apparatuses, after the melting process by heating, the melt is generally discharged from the discharge port formed in the bottom of the furnace body by its own weight and discharged to the container. When such a melt is dispensed, if a high-temperature melt is directly introduced into the mold (mold), the melt is fused and fixed to the mold, and it is difficult to extract the molten solidified body. In addition, even if it can be extracted, the slag layer is damaged during extraction, or the interface between the slag layer and the metal layer is broken, which makes it difficult to handle. For this reason, it is a common practice to install a receiver in the mold, introduce a melt into the mold and solidify by cooling, and then remove the solidified body integrated with the receiver from the mold (Patent Document 1). 2). Conventionally, the solidified body produced in this way is generally extracted from the mold together with the receiver without any special treatment before extraction.

  On the other hand, when discharging the melt, in order to avoid the problem that the melt exceeds the capacity of the receiver and overflows around the equipment (overflow), the mold has a space for holding the melt overflowing above the receiver. (Ie, the mold depth is deeper than the receiver height).

  The melt (molten metal) introduced into the receiver is separated into a lower metal layer and an upper slag layer depending on the density difference, but the nitrogen dissolved in the high-temperature molten metal during the melting process during the cooling process Gas is released as the solubility decreases. As a result, the released nitrogen gas rises in the metal layer and reaches the slag layer, and the slag layer is raised, and the slag layer is solidified with bubbles remaining inside, and the melt overflows from the receiver. In other words, a phenomenon may occur in which it adheres to the receiver flange and the upper and upper inner surfaces of the mold (Patent Document 3, Non-Patent Documents 1 and 2).

  Furthermore, when the melt is introduced into the receiver installed in the mold, the characteristics at the time of discharge (the flow rate is reduced at the final discharge stage and the molten metal is drawn in the circumferential direction due to the surface tension of the molten metal when it becomes an annular discharge flow. The molten material that is discharged by the surroundings or the molten metal may be transferred through the discharge nozzle) or the characteristics of the discharge mechanism (the furnace type that controls the discharge of the melt by the rotation control of the rotary furnace) The centrifugal force due to the rotation of the furnace acts and scatters to the surroundings), so that the entire amount of the melt is not discharged into the receiver, and a part of the melt scatters and adheres to the receiver flange and the upper and upper inner surfaces of the mold. May end up. In addition, even the melt discharged into the receiver will collide with the bottom of the receiver or the melt previously discharged into the receiver and bounce back to form droplets that adhere to the receiver flange and the upper and upper inner surfaces of the mold. There are things to do.

As a result of these phenomena, the apparent density of the slag layer is reduced due to the solidification of the slag layer with bubbles remaining therein, and the volume reduction effect is reduced. In addition, the state in which the slag adheres to the receiver flange portion and the upper and upper inner surfaces of the mold becomes an obstacle when the receiver is pulled out of the mold, and in severe cases, it may be substantially difficult to pull out.
JP 2001-228294 A JP-A-9-90096 JP 2004-184358 A “Standard production method of filled solids”, March 2005 revision 3, 9 companies outside Hokkaido Electric Power "Disposal confirmation method for plasma melted solids", JNES-SS report, 405, April 2005, Japan Nuclear Safety Infrastructure Organization Standards Standards Department

  Regarding the problem of bubbles remaining inside the slag layer as described above, it has been proposed in Patent Document 3 to add a bubble generation inhibitor, but the effect is not always sufficient. As for the problem of scattering when the melt is introduced into the receiver installed in the mold, it may be possible to install a guide in the discharge path of the melt. It is difficult. Therefore, it is conceivable to remove the solidified material (slag, metal, etc.) adhered and solidified by human power or the like, but it is difficult to remove it efficiently and completely. In addition, when melting radioactive solid waste generated from nuclear power plants etc., radioactive materials are contained in the melt and solidified material, so it is not preferable to work manually because it avoids radiation exposure. .

  The present invention solves such a problem and makes it possible to easily remove the solidified material adhering to the voids in the upper layer of the slag layer, the receiver flange, and the upper and upper inner surfaces of the mold, and to easily extract the receiver from the mold. An object of the present invention is to provide a pretreatment device.

  As a result of intensive studies to achieve the above object, the present inventor can automatically and surely remove the solidified material adhering to the voids in the upper layer of the slag layer by using a pretreatment device that combines a plurality of specific knockers and cleaners. It has been found that this is possible and that it is possible to easily remove the receptor from the mold over a long period of time, and the present invention has been completed.

That is, the present invention introduces a melted and solidified material that is used when a molten product discharged from a furnace is introduced into a receiver installed in a mold and cooled and solidified, and then a solidified body integrated with the receiver is removed from the mold. A body pre-treatment device,
A slag knocker (1) that flattenes the slag layer by crushing the voids above the melt-solidified slag layer by an excitation force;
A mold upper surface knocker (2) that vibrates a jig with a protrusion on the tip with a rotating cam and peels off the solidified material adhering to the upper surface of the mold;
While rotating the shaft with multiple chains, wires, etc. attached to the tip, it moves along the inner surface of the mold upper surface, the receiver flange surface, and the inner surface of the body portion. A mold inner surface impact cleaner (3) for crushing, peeling and removing the solidified material adhering to the inner surface of the body part;
A mold upper surface cleaner (4) comprising an electric rotating brush for removing the solidified material separated by the mold upper surface knocker (2);
Receptor upper surface cleaner (5) consisting of an electric rotating brush that removes solidified material on the upper surface of the receiver crushed by the mold inner surface impact cleaner (3)
Is a pre-drawing pretreatment device for a melt-solidified body.

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

  FIG. 3 is a schematic cross-sectional view showing a state in which the melt discharged from the furnace is introduced into a receiver installed in the mold and cooled and solidified.

  As described above, the melt (molten metal) introduced into the receiver 6 is separated into a lower metal layer 7 and an upper slag layer 8 due to the density difference. Nitrogen gas dissolved in the metal is released as the solubility decreases, raising the slag layer, solidifying the slag layer with bubbles 9 remaining inside, or the melt overflowing from the receiver The flange portion 10 and the upper surface 12 and the upper inner surface 13 of the mold 11 may adhere.

  Furthermore, the molten material may adhere to the receiver flange portion and the upper and upper inner surfaces of the mold due to scattering when the melt is introduced into the receiver installed in the mold.

  The problem of bubbles remaining in the slag layer can be improved by a method of adding a bubble generation inhibitor or the like, but it is difficult to completely prevent generation.

  In addition, it is difficult to completely prevent splashing when the melt is introduced into a receiver installed in the mold.

  Therefore, the slag adhering to the voids in the upper layer of the slag layer may be removed by human power or a processing apparatus, but it is difficult to remove it efficiently and completely. That is, the scattered melt / slag contains iron oxide and the like, and is hard and solidified. Therefore, even if an appropriate jig is used by human power, it is very laborious. Furthermore, there are various types of scattered matter attachments, such as thick and non-sticky parts, hard and non-sticky parts depending on the location. Can't respond to changes and doesn't work well (can't be completely removed or bite to stop functioning, etc.)

  The present invention solves such a problem and automatically and reliably removes the solidified material adhered thereto.

  The extraction pretreatment apparatus of the present invention comprises a slag knocker (1), a mold upper surface knocker (2), a mold inner surface impact cleaner (3), a mold upper surface cleaner (4), and a receiver upper surface cleaner (5).

  The procedure of the treatment according to the present invention is not particularly limited, but it is preferable in terms of work efficiency to carry out in the order of (1) to (5). That is, the voids of the melted solid slag layer are crushed with the slag knocker (1), the mold upper surface knocker (2) and the mold inner surface impact cleaner (3), the mold upper surface, the mold upper inner surface (usually in a conical shape), the receiver The solidification of the flange surface and the inner surface of the body part is peeled off, and finally the peeled piece remaining on the upper surface of the mold, the upper surface of the upper part of the mold, the inner surface of the receiver flange surface and the inner surface of the body by the mold upper surface cleaner (4) and the receiver upper surface cleaner (5). It is desirable to remove (drop the peeled piece to the receiver).

  In the treatments (1) to (5), it is preferable to carry out the process while rotating the mold at a low speed (about 0.1 to 10 rpm, preferably about 0.3 to 3 rpm). By rotating the mold, the knockers and cleaners (1) to (5) need not be moved in the circumferential direction.

  FIG. 2 is a diagram showing the operation status of the slag knocker (1) and the mold inner surface impact cleaner (3). FIG. 3 is an operation of the mold upper surface knocker (2), the mold upper surface cleaner (4), and the receiver upper surface cleaner (5). It is a figure which shows a condition.

  As shown in FIG. 2, the slag knocker (1) has a function of crushing and flattening the voids in the upper part of the melt-solidified slag layer by an exciting force. The device configuration is not particularly limited as long as it has a mechanism for crushing the gap. Further, the mold inner surface impact cleaner (3) is configured to rotate the shaft (3-2) having a plurality of chains, wires (3-1) and the like attached to the tip while rotating the mold upper inner surface, the receiver flange surface, and the inner surface of the trunk portion. The slag and metal adhering to the inner surface of the upper part of the mold, the inner surface of the receiver flange and the inner surface of the body portion are crushed, peeled off and removed by mechanical impact. The solidified product on the inner surface of the upper part of the mold, the flange surface of the receiver, and the inner surface of the body part is icicle-shaped, and there are places where it adheres thickly or thinly. Uniform removal with a cutter or the like is difficult. In the present invention, the solidified material is crushed and peeled by a mechanical impact caused by the rotation of such a chain or wire.

  The mold inner surface impact cleaner (3) rotates a shaft on which a plurality of chains having appropriate lengths are attached at a relatively high speed (about 500 to 5000 rpm, preferably about 1000 to 1200 rpm) to hit a chain, a wire, etc. The solidified material is crushed and peeled off by the impact caused by.

  Next, as shown in FIG. 3, the mold upper surface knocker (2) peels off the slag adhering to the upper surface of the mold by vibrating a jig (2-1) with a protrusion provided at the tip with a rotating cam. To do. The shape and size of the protrusions are not particularly limited as long as the slag attached to the upper surface of the mold can be peeled off by an appropriate excitation force.

  The mold upper surface cleaner (4) and the receiver upper surface cleaner (5) are each composed of an appropriate electric rotating brush, and the mold upper surface cleaner (4) removes the solidified material peeled off by the mold upper surface knocker (2). (5) has a function of removing the solidified material on the upper surface of the receiver crushed by the mold inner surface impact cleaner (3) (dropping the remaining peeled piece onto the receiver).

  In order to move the knockers and cleaners of (1) to (5), known means such as an air cylinder and an electric cylinder can be used.

  The processing steps using (1) to (5) are usually completed in about 20 minutes.

It is a figure which shows the operating condition of a slag knocker (1) and a mold inner surface impact cleaner (3). It is a figure which shows the operating condition of a mold upper surface knocker (2), a mold upper surface cleaner (4), and a receiver upper surface cleaner (5). It is a schematic cross-sectional view showing a state in which a melt discharged from a furnace is introduced into a receiver installed in a mold and cooled and solidified.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Slag knocker 2 Mold upper surface knocker 3 Mold inner surface impact cleaner 4 Mold upper surface cleaner 5 Receptor upper surface cleaner 6 Receptor 7 Metal layer 8 Slag layer 9 Air gap (bubble)
DESCRIPTION OF SYMBOLS 10 Receptor flange part 11 Mold 12 Upper surface of mold 13 Upper inner surface of mold

Claims (2)

After the melt discharged from the furnace is introduced into a receiver installed in the mold and cooled and solidified, pre-treatment for extracting the solidified solid used for extracting the solidified body integrated with the receiver from the mold A device,
A slag knocker (1) that flattenes the slag layer by crushing the voids above the melt-solidified slag layer by an excitation force;
A mold upper surface knocker (2) that vibrates a jig with a protrusion on the tip with a rotating cam and peels off the solidified material adhering to the upper surface of the mold;
While rotating the shaft with multiple chains, wires, etc. attached to the tip, it moves along the inner surface of the mold upper surface, the receiver flange surface, and the inner surface of the body portion. A mold inner surface impact cleaner (3) for crushing, peeling and removing the solidified material adhering to the inner surface of the body part;
A mold upper surface cleaner (4) comprising an electric rotating brush for removing the solidified material separated by the mold upper surface knocker (2);
Receptor upper surface cleaner (5) consisting of an electric rotating brush that removes solidified material on the upper surface of the receiver crushed by the mold inner surface impact cleaner (3)
A pre-drawing device for melted and solidified products in combination. The apparatus for pre-drawing the melt-solidified product according to claim 1, wherein the melt contains radioactive miscellaneous solid waste.

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