JPH0238900A - Removal and remover of stuck dust in off-gas piping in glass melting furnace - Google Patents

Abstract

PURPOSE:To improve an efficiency of a removal operation by inserting a remover of stuck dust into an off-gas piping and by contacting an outer circumferential surface of the remover to an inner surface of the off-gas piping to remove the dust stuck on the surface. CONSTITUTION:A sluice valve 7 for keeping gas tightness is provided at an upper wall of a glass melter furnace 1 to shut off an interconnection with an off-gas piping 2. At an ordinary discharging of off-gas, cooling air is blown into the off-gas piping 2 from a blowing-in nozzle via a feed-er pipe 4 of the cooling air and a blowing-in part 3 of the cooling air. The dust is cooled off by the cooling air blown-in to be transformed to be hard to stick, and to form a air layer between the off-gas and an inner surface of the off-gas piping 2, as well, so that the dust becomes hard to stick to the inner surface of the piping and sticking of the dust is prevented therewith. In this way, a stuck dust can be removed without interrupting the off-gas flow.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a method for removing adhering dust from off-7y space piping in a plus melting furnace and a removing body used in the removal method, and more preferably to a removal body for use in the removal method. The present invention relates to a method for removing dust adhering to the inner surface of an off-gas pipe in a plus melting furnace for solidifying high-level radioactive liquid and radioactive waste, and a removing body used in the method.

(Prior Art) In nuclear reactor facilities, high-level radioactive liquid waste and radioactive waste are melted together with 77'2 gas raw materials in a plus melting furnace and assimilated into radioactive materials to make them suitable for disposal.

By the way, in a plus melting furnace, the off-gas mixed with dust from inside the furnace is discharged through the off-gas piping, and if the dust in the off-gas is left to adhere to the inner surface of the off-gas piping, the off-gas piping may become clogged. There is a risk that it will happen.

Therefore, conventionally, by blowing cooling air into the pipe from the outer circumference of the off-gas piping, the dust is cooled and made less likely to adhere, and an air layer is formed between the off-gas pipe and the inner surface of the off-gas pipe. Adhesion prevention methods are being implemented to prevent dust from coming into contact with the inner surface of piping.

On the other hand, a method has also been proposed in which the attached dust is removed using a brush or the like.

(The problem that the invention aims to solve ff1) However, the above-mentioned conventional technology has a similar problem.

Even with the method of preventing dust adhesion by blowing cooling air, it is impossible to completely prevent dust adhesion.

In addition, removal methods using brushes are inefficient because they have to be moved back and forth several times, and there is a risk of uneven removal of adhering dust.Furthermore, the brushes used to remove dust become new radioactive waste. There is.

SUMMARY OF THE INVENTION Therefore, the object of the present invention is to provide a method for removing adhering dust from off-gas piping in a glass melting furnace, which can reliably remove dust and does not generate new radioactive waste, and a method for removing adhering dust used in the removal method. The objective is to provide a removal body.

(Means for Solving the Problems) In order to achieve the above object, the present invention is configured as follows.

That is, the present invention slides a cylindrical removing body made of positive fiber inside an off-gas pipe, thereby removing dust adhering to the inner surface of the off-gas pipe, and removing the used removing body from a plus This prevents the generation of secondary waste by putting it into a melting furnace and melting it.

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

Referring to FIG. 1, the upper wall of the glass melting furnace 1 is provided with an off-slot Ir1!2 for taking the office from the inside of the glass melting furnace 1 to the outside of the furnace. Normally, the amount of attached dust tends to increase as the side of the off-gas pipe 2 is closer to the glass melting furnace 1. In addition, the outer diameter of the removing body 6 (described later) is gradually reduced as its pushed length increases (
There is a tendency. Therefore, the diameter of the off-gas pipe 2 is tapered so that it decreases as it approaches the plus melting furnace 1.
When the attached dust removal body 11a described later is inserted, the contact pressure with the inner surface of the off-gas pipe 2 is increased to increase the dust removal effect.

A cooling air blowing section 3 is provided so as to cover the outer circumference near the base end of the off-7y space distribution ff 2, and this cooling air blowing section 3
An air supply pipe 4 is provided for supplying cooling air to.

The off-gas pipe 2 is provided with an inlet 5 passing through the pipe wall. The blow-in port 5 is perforated so as to be inclined in the direction in which the off-gas flows, and blows cooling air into the off-gas pipe 2 in the same direction as the direction in which the off-gas flows.

A remover supply pipe 6 is provided in the off-gas pipe 2 and serves as a guide for inserting the adhering dust remover 11a described later into the off-gas pipe 2, and the off-gas pipe 2 is connected to the middle of the off-gas pipe 2. A gate valve 7 for maintaining airtightness is provided to shut off the air. A piston drive section 8 is removably installed at the upper end of the removal body supply pipe 6 via a seven-piece run 9, and the piston drive section 8 is provided with a piston 10a that pushes the removal body 11a.

The piston 10a has an attached dust removing body 11a at its tip.
Press the removal body 11g to supply the removal body Ir! The removing body 11a is pushed through the inside of the off-7y space pipe 2 and dropped into the furnace. The attached dust removal body 11a is made of glass fiber, and is formed in a size and shape that matches the inner surface of the off-ff space piping 2, and in this embodiment, it is formed in a solid cylindrical shape.

The shape of the removing body 11a is such that when removing dust from the off-gas piping of a glass melting furnace during continuous feeding, the dust removing body 11b is formed into a hollow shape as shown in FIG. It is desirable to have a structure that allows the off-7ys to flow through the piston and does not obstruct the flow of the off-7y as much as possible, such as by making the push plate 12 of the piston 10b annular, as shown in Figure f53.

The present embodiment configured as described above operates as follows.

During normal off-gas discharge, the off-gas pipe 2 is connected to the air inlet 5 via the cooling air supply pipe 4 and the cooling air blowing section 3.
Cooling air is blown inside. This blowing of cooling air cools the dust and makes it less likely to adhere to the dust, and the off-gas and off-gas piping 2 are formed to make it difficult for the dust to come into contact with the inner surface of the piping, thereby preventing dust from adhering.

Despite this blowing of cooling air, off-gas distribution W2
Dust adheres to the inner surface of the

Therefore, remove the attached dust according to the following operating sequence.

(2) Remove the 7-lunge 9 of the piston drive unit 8 from the removal body supply pipe 6 by remote control using a manipulator (not shown), and set the removal body 11a in the position indicated by the dotted line in figure f51 in the removal body supply pipe 6.

Then, attach the 7-run 9 and connect the piston drive unit 8 to the removal body supply pipe 6).

In this case, the gate valve 7 is closed.

(2) Next, the gate valve 7 is opened, the piston drive unit 8 is operated to push down the piston 10a, and the removal body 11a is pushed into the off-gas pipe 2.

Then, the outer periphery of the removing body 11a is inside the off-gas pipe. Remove dust adhering to the surface.

(2) Then, the removing body 11a is pushed further and the removing body 11a is dropped into the glass melting furnace 1. The dropped removal body 11a and the dust attached thereto are melted in the glass melting furnace 1 and vitrified together with the radioactive waste liquid and radioactive waste to be solidified.

Therefore, there is no secondary generation of radioactive waste.

■ Next, drive the piston drive unit 8 and the piston 1
0a is contracted and the gate valve 7 is closed.

In addition, in the above operation, if the adhering dust removal operation is performed while operating the melting furnace 1, please refer to Figs. 2 and 3.
As shown in the figure, it is desirable to use a hollow cylindrical remover 11a and to make the push plate 12 at the tip of the piston 10a annular. This makes it possible to remove adhering dust without obstructing the flow of off-gas.

Furthermore, in the above embodiment, the method of blowing cooling air into the off-gas piping is also used as a dust adhesion prevention method, but it is understood from the above-mentioned book that the present invention also includes a method excluding the method of blowing cooling air. This is obvious from the point of view of the invention.

Furthermore, the present invention is not limited to a plus melting furnace for treating radioactive liquid waste and radioactive waste from nuclear reactor equipment, but is applicable to general glass melting furnaces for waste liquid treatment and waste treatment. It is something.

(Effects of the Invention) According to the present invention, the adhering dust removing body is inserted into the off-gas piping, and the outer periphery of the removing body is brought into contact with the inner surface of the off-gas piping to remove the adhering dust. The attached dust can be removed reliably, and the efficiency of the adhering dust removal operation is very high.

In addition, since the dust removal body is made of glass fiber, it is melted by putting it into a glass melting furnace and used as solidified layer glass, which creates new waste or secondary radioactive waste. There is no generation of objects.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing one embodiment of the present invention. FIG. 2 is a perspective view showing a modification of the dust removing body. FIG. 3 is a perspective view showing a modification of the piston. 〃Las melting furnace 2〃Nio 7〃S pipe cooling air blowing $ 4: Cooling air supply pipe inlet 6
: Remover supply pipe gate valve 8: Piston drive unit 7 langes 10a, 10b: Pistons 1a, 11b: Dust remover 12: Push plate agent Patent attorney Mibe Tsuji (and 1 other person) Figure

Claims (2)

[Claims] (1) Form a removal body for adhering dust using glass fiber in a size and shape that matches the inner surface shape of the off-gas piping,
The removing body is inscribed and inserted into the off-gas piping, the removing body is slid along the off-gas piping, thereby removing dust adhering to the inner surface of the off-gas piping, and the removing body is placed in a glass melting furnace. A method for removing dust adhering to off-gas piping in a glass melting furnace, characterized by charging the dust into a glass melting furnace and melting it. (2) A glass fiber is formed into a size and shape that matches the inner surface shape of the off-gas piping, is inserted internally into the off-gas piping, and is slid along the off-gas piping to remove dust attached to the inner surface of the off-gas piping. A device for removing dust adhering to off-gas piping in a glass melting furnace.