KR20120049660A - An abrasive blasting apparatus for decontaminating the inner surface of contaminated bundle tubes in steam generator - Google Patents

Abstract

PURPOSE: An abrasive spraying apparatus for decontaminating an inner surface of a contaminated tube bundle of a steam generator is provided to efficiently remove contaminated radionuclides from an inconel tube. CONSTITUTION: A spraying nozzle(11) sprays abrasive to the inner surface of an inconel tube. A protection room(12) induces the abrasive after the inner side of the inconel tube is decontaminated. A cyclone(13) generates negative pressure to move the abrasive to the protection room. A storage tank(15) reuses the abrasive after the abrasive collected by the cyclone is stored. A dust collector(16) collects and removes inconel dust and abrasive dust. A control plate(17) controls the operation of an apparatus.

Description

An abrasive blasting apparatus for decontaminating the inner surface of contaminated bundle tubes in steam generator}

The present invention relates to a decontamination apparatus capable of removing radionuclides from the inner surface of a bundle of Inconel tubes in a steam generator operating in a nuclear power plant. More particularly, the present invention relates to a decontamination apparatus of an Inconel tube for decontaminating the inner surface of an Inconel tube. The present invention relates to providing an abrasive spray suitable for contamination characteristics.

In general, in a nuclear power plant, the inner surface of a bundle of inconel tubes constituting the steam generator is contaminated with cobalt, cesium, etc. due to long-term operation of the steam generator. Radioactive metal waste generation is foreseen.

Therefore, in order to reduce such metal waste generation amount, development of a decontamination apparatus capable of removing radionuclides from the inner surface of the Inconel tube bundle is required, and research on this has been actively conducted.

As an example of the conventional decontamination apparatus as described above, for example, as described in Korean Patent No. 10-0548640 (registered on January 25, 2006), the radioactive contamination metal decontamination apparatus of the neutral salt electropolishing method capable of electrolytic solution recycling. "There is.

More specifically, the above-mentioned "neutral salt electropolishing method radioactive contamination metal decontamination apparatus of the electrolytic solution recycling" of the Patent No. 10-0548640, the first electrolyte storage tank for temporarily storing the electrolyte, the first electrolyte storage tank An electrolytic polishing bath for receiving electrolytic solution from electrolytic polishing and electropolishing radioactive contaminants with neutral salt, a power supply unit for supplying power to the electrolytic polishing bath, a sludge storage unit for temporarily storing the electrolytic solution subjected to decontamination in the electrolytic polishing bath, A chromium ion removal unit for precipitating and removing chromium ions from an electrolyte solution supplied from the sludge storage unit, a sludge separation unit for separating sludge in which heavy metal components including chromium ions are deposited from the electrolyte solution, and an electrolyte solution in which the heavy metal sludge is separated It is comprised including the 2nd electrolyte storage tank supplied to the said 1st electrolyte storage tank.

That is, according to the decontamination apparatus of Patent No. 10-0548640 as described above, after solving the disadvantages of the decontamination apparatus using a conventional neutral salt electrolytic polishing, after removing the chromium ions present in the ionic state in the electrolytic solution subjected to decontamination treatment The decontamination process is continuously carried out by separating the sludge from the electrolyte so that the electrolyte can be continuously recycled, and the electrolyte is continuously introduced into the electrolytic polishing bath, the overflowing electrolyte is circulated to remove the sludge, and then the electrolytic polishing bath is added again. In addition, by the continuous circulation of the electrolyte to be cooled by the natural air cooling method by a separate cooling device and a cooling circulation pipe is not required, the neutral salt electropolishing method of the radioactive contamination metal decontamination apparatus having a simple structure Is provided.

Therefore, according to the decontamination apparatus of Patent No. 10-0548640 as described above, the electrolyte can be recycled by continuously recycling the electrolyte, and the configuration is simple and the cost is reduced.

In addition, as another example of the prior art as described above, there is, for example, "decontamination and dust collector of radioactive material using high pressure" as disclosed in Korean Patent No. 10-0571564 (registered on April 10, 2006). .

More specifically, the above-mentioned Patent No. 10-0548640, "Decontamination and dust collection device of radioactive material using high pressure", the surface, such as equipment, buildings, equipment and inner walls, floors, ceilings and the like contaminated with radioactive material In order to remove the radioactivity quickly and efficiently, the high pressure generating means for supplying compressed air after mixing and mixing sodium bicarbonate or dry ice, and the gas of the high pressure generating means is injected toward the decontamination surface and the other side A decontamination head to be suctioned, a vacuum pump having an input side connected to a suction line of the decontamination head, a dust collecting device having an output side of the vacuum pump extending inside and filled with water, and connected to an upper portion of the dust collecting device, A dehumidifier for dehumidifying the air in the dust collector, an air filter for filtering the dehumidified air, and a lower part of the dust collector. And a centrifugal separator for separating the precipitated material in the dust collecting apparatus, the temporary storage tank for the separated liquid by a centrifugal separator, and one side is configured to include a liquid filtering device coupled to the temporary tank.

Therefore, according to the decontamination and dust collector of the Patent No. 10-0548640, the conventional decontamination method such as so-called 'high pressure decontamination' spraying dry ice or sodium bicarbonate, while the removal performance of the contaminated epoxy is stabilized, but scattered To prevent this, the use of a dust collector equipped with an air filter will result in coarse particles of the waste, so that the filter is replaced more frequently, and the amount of contaminated waste filter is increased. In order to solve the conventional problems of side effects, the amount of waste generated is much smaller than that of conventional dust collection facilities, and a decontamination and dust collecting apparatus for surface radioactive material using high pressure which can be decontaminated even in a place without a separate disposal facility is provided.

In addition, as another example of the prior art as described above, for example, "Physical decontamination apparatus for removing radioactive contaminants in the steam generator chamber" as disclosed in Korean Patent Registration No. 10-0583142 (registered May 17, 2006) There is.

More specifically, the "Physical decontamination apparatus for removing radioactive contaminants in the steam generator chamber" of the Patent No. 10-0583142 is a compressed air providing unit for providing compressed air, and one end of the compressed air providing unit In addition, the other end is connected to the injection hose for removing contaminants, and the dry ice providing unit for mixing the dry ice pellets into the compressed air and discharged to the injection hose, and by sucking the pollutants scattered by the injection hose It comprises a dust suction unit equipped with a suction hose on one side to collect, and a dust collector connected to the dust suction unit by a hose to filter the dust from the dust suction unit.

Therefore, according to the decontamination apparatus of Patent No. 10-0583142, water washing and steam washing, which are widely used in the related art, are excellent in cleaning efficiency but difficult to collect pollutants, and also increase the exposure of workers. Overcoming, there is provided a physical decontamination apparatus for removing radioactive contaminants in a steam generator chamber that can clean highly radiated equipment at low cost and high efficiency, capture contaminants, and reduce radiation exposure.

In addition, as another example of the prior art as described above, there is, for example, "water chamber decontamination apparatus for a steam generator of a nuclear power plant" as disclosed in Korean Patent No. 10-0357229 (registered on October 5, 2002).

More specifically, the above-described Patent No. 10-0583142, "Water chamber decontamination apparatus for a steam generator of a nuclear power plant," has a guide groove having a constant width and serves as a guide rail and a flat base plate along the guide groove. It is installed to move horizontally and has a nozzle body having upper and lower nozzles, which are spraying means and upper and lower rollers, respectively, which are installed at the upper and lower ends thereof, and are connected to the nozzle body and the piston rod at the rear end of the base plate, so that the nozzle body is horizontal. It comprises an air cylinder that serves as a driving source during movement and a water pump connected to the nozzle body and a water supply hose to supply water of high pressure.

Therefore, according to the steam generator decontamination apparatus configured as described above, the conventional method has an exposure of about 35 mRem when one worker is working to the hot / cold leg at the inlet and outlet of the steam generator. It is difficult to carry out decontamination for a long time because it is a high radiation area, and it is difficult to expect a decontamination effect. It was difficult to decontaminate it. Also, if decontamination is not carried out, overexposure is necessary. If the amount of water used is less than 100 liters of boric acid and pure water, the decontamination effect is insignificant. Provides a decontamination device that can be used to reduce radiation exposure and avoid work avoidance in high-radiation areas. It can improve competitiveness.

However, the conventional decontamination apparatus as described above, the mixture of sodium bicarbonate or dry ice and compressed and supplied through a high pressure line, or by mixing dry ice pellets in the compressed air and discharged to the injection hose, or Since the method of spraying water of high pressure was used, there existed a problem similar to the conventional high pressure decontamination method eventually.

In addition, in order to effectively remove radionuclides on the inner surface of the Inconel tube bundle in a steam generator operating in a nuclear power plant, it is necessary to provide a decontamination apparatus or a spraying device on the inner surface of the Inconel tube suitable for the contamination characteristics of the Inconel tube. Preferably, however, there has not yet been provided a decontamination apparatus for the inner surface of the Inconel tube that satisfies all such requirements, and a polishing spray suitable for the contaminant characteristics of the Inconel tube.

The present invention seeks to solve the problems of the prior art as described above, and therefore an object of the present invention is to provide a decontamination apparatus capable of removing radionuclides on the inner surface of an Inconel tube bundle, which is suitable for the contamination characteristics of the Inconel tube. It is to provide the abrasive spray value.

In order to achieve the object as described above, according to the present invention, in the abrasive spray device for decontaminating the inner surface of the steam generator contaminated tube bundle, injecting an abrasive on the inner surface of the Inconel tube to decontaminate the inner surface of the Inconel tube A spray nozzle, a protection room for guiding the abrasive after the abrasive sprayed from the jet nozzle decontaminates the interior of the Inconel tube, and a negative pressure to move the abrasive after decontamination to the protective chamber. Cyclone for generating, a cyclone pan installed in the cyclone, a storage tank for storing and reusing the abrasive collected through the cyclone, inconel dust and abrasive dust ( controlling the operation of the dust collector and the apparatus as a whole to collect and remove abrasive dust The abrasive-jet apparatus including a control unit, characterized in that configured is provided.

Here, the decontamination is characterized in that the inner surface of the Inconel tube contaminated by the abrasive fired from the injection nozzle is formed to be etched.

In addition, the abrasive, after decontaminating the inside of the Inconel tube hits the back wall in the protective chamber and falls to the bottom, at this time, the negative pressure is generated by the operation of the cyclone fan is collected from the protective chamber to the storage tank through the cyclone After being reused.

In addition, the dust collector is characterized in that it is configured to collect and remove the Inconel dust and fine abrasive dust generated during the decontamination process.

Furthermore, the Inconel tube bundle of the steam generator is composed of about 3,400 Inconel tubes, each Inconel tube is bent in a U-shaped, characterized in that the length is about 20m.

In addition, the abrasive is characterized in that configured to use alumina (Alumina) or silicon carbide (Silicon carbide).

In addition, the Inconel tube, or raw inconel tube (raw inconel tube), or to immerse the raw inconel tube in an EDTA solution-filled autoclave to reproduce the actual inconel tube oxidized by prolonged radiation and 270 ° It is characterized in that the oxidized inconel tube (oxidized inconel tube) prepared by oxidizing for 72 hours at C.

In addition, the apparatus is characterized in that configured to adjust the spraying distance of the abrasive according to the degree of contamination of the Inconel tube.

In addition, the apparatus is characterized in that configured to adjust the injection time of the abrasive according to the degree of contamination of the Inconel tube.

In addition, the generated air pressure in the abrasive spray device is characterized in that 5 to 10 atm.

Further, according to the present invention, in the decontamination method for decontaminating the inner surface of the steam generator contaminated tube bundle, using the above-described abrasive spray value and using alumina # 80 as the abrasive, Provided is a decontamination method for decontaminating an inner surface of a bundle of steam generator contaminated tubes, characterized by performing an operation for decontaminating the inner surface.

Further, according to the present invention, in the decontamination method for decontaminating the inner surface of the steam generator contaminated tube bundle, the steam generator contaminated tube is used by using the above-described abrasive spraying device and using silicon carbide # 80 as an abrasive. A decontamination method is provided for decontaminating a steam generator contaminated tube bundle inner surface, characterized in that to perform decontamination of the inner surface of the bundle.

Here, the methods, characterized in that the weight loss of the Inconel oxide tube per injection distance is reduced by 32.8%.

In addition, the methods are characterized in that the weight loss increases about 2.8 times when the injection time is increased three times.

In addition, the above methods are characterized in that the weight loss of the inner surface of the oxide inconel tube by the silicon carbide as the abrasive is increased by 32.3% than that by the alumina.

As described above, according to the present invention, the present invention includes a spraying nozzle, a protection room, a cyclone, a cyclone pan, a storage tank, and a dust collector. A polishing spray apparatus for decontaminating the constructed steam generator contaminated tube bundle inner surface is provided.

That is, according to the present invention, the inner surface of the contaminated Inconel tube is etched by the abrasive injected from the nozzle by the abrasive spray device for decontaminating the inner surface of the steam generator contaminated tube bundle as described above, and the abrasive is an Inconel tube. After decontaminating the interior, it hits the inner wall of the protection room and falls to the floor.Negative pressure is generated by the operation of the cyclone fan, which is collected from the protection room through the cyclone and collected in the storage tank for reuse.Inconel dust is collected in the dust collector and then removed.

Therefore, according to the present invention, it is possible to provide an abrasive spraying apparatus for decontaminating the inner surface of the steam generator contaminated tube bundle, which is suitable for the contaminant characteristic of the Inconel tube, which can effectively remove contaminating nuclides inside the Inconel tube.

1 is a view schematically showing the overall configuration of the abrasive spray device for decontaminating the inner surface of the steam generator contaminated tube bundle according to the present invention, Figure 1a is a perspective view, Figure 1b is a partial enlarged detail showing the configuration of the protective chamber 1C is a side view of FIG. 1A.
FIG. 2 is a design diagram of an abrasive spraying apparatus for decontaminating the inner surface of the steam generator contaminated tube bundle according to the present invention shown in FIG. 1.
3 is a diagram schematically showing the configuration of a steam generator operating in a Korean ring power plant.
Figure 4 is a view showing the decontamination of the interior of the Inconel tube using the abrasive spraying device for decontaminating the inner surface of the steam generator contaminated tube bundle according to the present invention.
FIG. 5 shows alumina # 80 and silicon carbide # 80 as abrasives used for abrasive spray experiments.
6 is a view showing a state before and after abrasive spray decontamination of an inconel oxide tube.
7 is a diagram showing the weight loss inside the furnace inconel tube with respect to the injection distance.
8 is a view showing the weight loss inside the oxide inconel tube with respect to the injection distance.
9 is a view showing the weight loss inside the furnace inconel tube with respect to the injection time.
10 is a view showing the weight loss inside the oxide inconel tube with respect to the injection time.
11 is a diagram showing the weight loss inside the oxide inconel tube by alumina and silicon carbide for the injection distance.

Hereinafter, with reference to the accompanying drawings, it will be described in detail the abrasive injection device for decontaminating the inner surface of the steam generator contaminated tube bundle according to the present invention.

Here, it should be noted that the contents described below are only one embodiment for carrying out the present invention, and the present invention is not limited only to the contents of the embodiments described below.

That is, in the embodiment of the present invention described below, the Inconel tube bundle of the steam generator is composed of about 3,400 inconel tubes, each inconel tube is bent in a U-shape, the length is about 20m.

In addition, the present invention, as described below in the embodiments of the present invention described below, in order to decontaminate the inner surface of the Inconel tube, to design and fabricate the abrasive spray device suitable for the contamination characteristics of the Inconel tube, each decontamination experiment The effect of parameters on decontamination efficiency was analyzed.

To this end, the abrasive spray device according to the present invention is a spray nozzle, a protection room, a cyclone, a cyclone pan, an abrasive storage tank, a dust collector. In addition, the main parameters related to the removal efficiency of the abrasive injection device are distance from the nozzle, injection time, abrasive type, injection pressure and the like.

In addition, the present invention, in order to secure the maximum removal efficiency, through the experiment analyzed the effect of each parameter on the removal efficiency of the radionuclide contaminated inside the tube bundle.

As a result, the longer the injection distance from the nozzle, the lower the weight loss of the raw inconel tube and the oxidized inconel tube.

That is, in the case of Inconel oxide, the weight loss was reduced by about 32.8% per 1m, and the longer the injection time, the greater the weight loss on the inner surface.

More specifically, the weight loss increased by about 2.8 times when the injection time was increased three times, and the average weight loss of the inconel oxide tube was reduced by about 35% compared to the low inconel tube during the three minutes injection time.

This is presumed to be due to the formation of an oxide film on the inner surface of the inconel oxide tube, and the weight loss of the inner surface of the oxide inconel tube by silicon carbide as a propellant is about less than that caused by alumina. 32.3% increase.

Therefore, it can be seen that it is more effective to use silicon carbide as an abrasive.

Subsequently, with reference to the drawings, the detailed configuration of the abrasive spray device for decontaminating the inner surface of the steam generator contaminated tube bundle according to the present invention as described above will be described.

First, referring to FIG. 1, FIG. 1 schematically shows the overall configuration of an abrasive spray apparatus for decontaminating the inner surface of a bundle of steam generator contaminated tubes.

In addition, referring to FIG. 2, FIG. 2 is a design diagram of an abrasive spray device for decontaminating the inner surface of the bundle of steam generator contaminated tubes according to the present invention shown in FIG.

That is, as shown in Figure 1, the abrasive spray device 10 for decontaminating the inner surface of the steam generator contaminated tube bundle according to the present invention, the inner surface of the Inconel tube 19 to decontaminate the inner surface of the Inconel tube (19) A spraying nozzle 11 for injecting an abrasive into the nozzle, a protection room 12 for inducing the abrasive after the abrasive injected from the nozzle decontaminates the interior of the Inconel tube, and the abrasive after decontamination A cyclone 13 for generating underpressure to move to the protective chamber 12, a cyclone pan (not shown) installed in the cyclone, and the abrasive collected through the cyclone 13; To control the storage of the storage tank 15 for reuse, the dust collector 16 for collecting and removing inconel dust and abrasive dust, and the operation of the entire apparatus. One control unit 17 is configured.

Subsequently, FIG. 3 is a diagram schematically showing the configuration of a steam generator operating at a Korean ring power plant.

That is, as shown in Figure 3, the Inconel tube bundle of the steam generator is composed of about 3,400 Inconel tubes, each inconel tube is bent in a U-shape, the length is about 20m.

In addition, Figure 4 is a view showing the decontamination of the interior of the Inconel tube using the abrasive spray device 10 produced as described above.

That is, in more detail, the specific operation of the abrasive injection device 10 for decontaminating the inner surface of the steam generator contaminated tube bundle according to the present invention as described above is as follows.

First, the inner surface of the contaminated Inconel tube 19 is etched by the abrasive fired from the nozzle 11 to perform decontamination.

Subsequently, the abrasive after decontaminating the inside of the Inconel tube 19 hits the rear wall 18 in the protective chamber 12 and falls to the bottom.

At this time, the abrasive after decontamination generates negative pressure by the operation of the cyclone fan, is collected from the protective chamber 12 through the cyclone 13, and is reused after being collected.

Inconel dust and abrasive dust are also collected by the dust collector 16 and then removed.

Therefore, as described above, the abrasive spray device 10 for decontaminating the inner surface of the steam generator fouling tube bundle according to the present invention can be constructed, and the inside of the Inconel tube as shown in FIG.

Next, the experimental results applied to the actual decontamination using the abrasive spraying device according to the present invention produced as described above will be described.

First, the main parameters related to the removal efficiency of the abrasive spraying device are distance from the nozzle, spraying time, abrasive type, spraying pressure and the like.

Therefore, the inventors of the present invention derived the effect of the main parameters on the removal efficiency of the contaminants in the Inconel tube through the following experiment using the abrasive spraying device manufactured as described above, and at this time, the maximum removal efficiency In order to ensure the effect, the effect on the removal efficiency of each parameter was analyzed.

That is, more specifically, for polishing spray experiments, as shown in FIG. 5, alumina # 80 and silicon carbide # 80 were used as the abrasive.

In addition, the tubes used in the experiments were prepared using raw inconel tubes and raw inconel tubes for the field simulation, ie, to reproduce the actual inconel tubes that had been radioactively contaminated and oxidized for a long time. An oxidized inconel tube prepared by immersion in an autoclave and oxidized at 270 ° C. for 72 hours was used.

Next, the inconel tube weight was measured before and after the abrasive spray to evaluate the etch rate inside the inconel tube.

At this time, the experiment was performed by varying the distance from the nozzle, the injection time, and the kind of the abrasive to select the optimum decontamination condition, and the injection pressure was maintained at 5 atm in all experiments.

In addition, the total length of the simulated SUS tube used in the experiment was 5m, which was separated into 5 pieces of 1m each.

In addition, 3 cm of Inconel tube and oxidized Inconel tube specimens were inserted into the connector at 1 m, 2 m, 3 m, and 4 m points, and the Inconel tube specimens were separated to measure the etch weight after the abrasive spray test.

In addition, the experiment was carried out for 3, 6 and 9 minutes for the furnace inconel tube and the oxide inconel tube, respectively.

Subsequently, with reference to Figs. 6 to 11, the experimental results of the experiment performed under the conditions as described above will be described.

Figure 6 is a photograph before and after the abrasive spray decontamination for the oxidized Inconel tube, it can be confirmed that the oxidized portion, that is, the black portion inside the Inconel tube after the abrasive spray is removed.

In addition, the inventors of the present invention analyzed the effect on the removal efficiency of each parameter through experiments, in order to secure the maximum removal efficiency of the abrasive injection device.

That is, FIGS. 7 and 8 show the weight loss inside the furnace inconel tube and the oxide inconel tube with respect to the injection distance, respectively.

As shown in FIG. 7 and FIG. 8, the longer the injection distance, the lower the weight loss of the low inconel tube and the inconel oxide tube was, and in the case of the inconel oxide tube, the weight loss was about 32.8% per 1m.

9 and 10 show the weight loss inside the furnace Inconel tube and the oxide Inconel tube with respect to the injection time.

9 and 10, the longer the injection time, the greater the weight loss of the inner surfaces of the furnace inconel tube and the oxide inconel tube.

That is, when the injection time increased three times, the weight loss increased about 2.8 times, and the average weight loss of the inconel oxide tube decreased about 35% compared to the low inconel tube during the three minutes injection time.

This may be due to the formation of an oxide film on the inner surface of the oxide inconel tube.

Next, FIG. 11 shows the weight loss inside the oxidized inconel tube by alumina and silicon carbide with respect to the injection distance.

As shown in FIG. 11, it can be seen that the weight loss of the inner surface of the oxide inconel tube by the silicon carbide as the propellant is increased by about 32.3% than that by the alumina.

Therefore, it can be seen from the foregoing that using silicon carbide as the abrasive is effective for removing contaminating nuclides inside the inconel oxide oxide.

In addition, the contents of the experimental results as described above are shown in the following [Table 1].

Result of abrasive spray decontamination test Item Experiment result Abrasive Injection Components blasting nozzle, protection room, cyclone, cyclone pan, abrasive storage tank, dust collector Optimum Polishing Agent Silicon carbide is effective because the weight loss of the inner surface of the oxidized inconel tube by silicon carbide is increased by about 32.3% than that by alumina. Distance from nozzle Decreased weight loss of about 32.8% per meter, the higher the decontamination efficiency Injection time When the injection time is increased 3 times, the weight loss is increased by about 2.8 times. Atmospheric pressure in the abrasive jet device 5-10 atmospheres Generated dust waste weight 0.2-0.4g / 1min? 5m

As described above, the details of the abrasive spray apparatus for decontaminating the inner surface of the steam generator contaminated tube bundle according to the present invention have been described through the embodiments of the present invention, but the present invention is only described in the above embodiments. The present invention is not limited, and therefore, it is obvious that various modifications, changes, combinations, and substitutions may be made by those skilled in the art according to design needs and various other factors. I will say.

10. Abrasive spraying device 11. Spray nozzle
12. Shelter 13. Cyclone
15. Storage tank 16. Dust collector
17. Control unit 18. Back wall
19. Inconel Tube

Claims (15)

In the abrasive spray device for decontaminating the inner surface of the steam generator contaminated tube bundle,
A spraying nozzle for spraying an abrasive on the inner surface of the Inconel tube to decontaminate the inner surface of the Inconel tube;
A protection room for inducing the abrasive after the abrasive sprayed from the spray nozzle decontaminates the inside of the Inconel tube;
A cyclone for generating negative pressure so that the abrasive after decontamination moves to the protective chamber,
A cyclone pan installed on the cyclone,
A storage tank for storing and reusing the abrasive collected through the cyclone;
A dust collector for collecting and removing inconel dust and abrasive dust, and
And a control unit for controlling the operation of the apparatus as a whole. The method of claim 1,
Wherein said decontamination is configured such that the inner surface of the Inconel tube contaminated by the abrasive fired from the spray nozzle is etched. The method of claim 1,
The abrasive is decontaminated in the Inconel tube and then hits the rear wall in the protective chamber and falls to the bottom. At this time, a negative pressure is generated by the operation of the cyclone fan and is collected from the protective chamber through the cyclone in the storage tank. Abrasive spraying device, characterized in that the reuse. The method of claim 1,
The dust collector, the abrasive spray device, characterized in that configured to collect and remove the Inconel dust and fine abrasive dust generated during the decontamination process. The method of claim 1,
The inconel tube bundle of the steam generator is composed of about 3,400 inconel tubes, each inconel tube is bent in a U-shape, the abrasive spray device, characterized in that the length is about 20m. The method of claim 1,
And the abrasive is configured to use alumina or silicon carbide. The method of claim 1,
The Inconel tube,
To reproduce the raw inconel tube, or the actual inconel tube that has been radioactively contaminated and oxidized for a long time, the raw inconel tube was immersed in an autoclave filled with EDTA solution and oxidized at 270 ° C. for 72 hours. Polishing spray device, characterized in that the prepared oxidized inconel tube (oxidized inconel tube). The method of claim 1,
The apparatus is abrasive polishing device, characterized in that configured to adjust the spraying distance of the abrasive according to the degree of contamination of the Inconel tube. The method of claim 1,
And the apparatus is configured to adjust the injection time of the abrasive according to the degree of contamination of the inconel tube. The method of claim 1,
And a generation pressure in the abrasive injection device is 5 to 10 atmospheres. In the decontamination method for decontaminating the inner surface of the steam generator contaminated tube bundle,
Using the abrasive spraying apparatus of Claims 1-10,
A decontamination method for decontaminating the inner surface of the steam generator contaminated tube bundle, characterized in that to perform decontamination of the inner surface of the steam generator contaminated tube bundle using alumina (Alumina) # 80 as an abrasive. In the decontamination method for decontaminating the inner surface of the steam generator contaminated tube bundle,
Using the abrasive spraying apparatus of Claims 1-10,
A decontamination method for decontaminating the inner surface of the steam generator contaminated tube bundle, characterized in that the operation of decontaminating the inner surface of the steam generator contaminated tube bundle using a silicon carbide (80) as an abrasive. The method of claim 11 or 12,
A decontamination method for decontaminating the inner surface of the steam generator contaminated tube bundle, characterized in that the weight loss of the Inconel oxide tube reduced by 32.8% per injection distance. The method of claim 11 or 12,
Decontamination method for decontaminating the inner surface of the steam generator contaminated tube bundle, characterized in that the weight loss increases by about 2.8 times when the injection time is increased by three times. The method of claim 11 or 12,
A decontamination method for decontaminating steam generator contaminated tube bundle inner surface, characterized in that the weight loss of the inner surface of the oxidized inconel tube by the silicon carbide as an abrasive is increased by 32.3% than that caused by alumina.

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