KR200318860Y1 - Ultrasonic decontamination system - Google Patents

Abstract

The present invention relates to an ultrasonic decontamination apparatus for decontaminating an object contaminated with radioactive material using ultrasonic waves, and more particularly, to an ultrasonic decontamination apparatus having a high decontamination efficiency and reducing generation of secondary wastes.

Ultrasonic decontamination apparatus according to the present invention, the decontamination tank 10 having a plurality of vibration elements 11 for generating a cavitation phenomenon in the decontamination solution;

A particulate filter 20 for filtering fine radioactive particles contained in the decontamination liquid discharged from the decontamination tank 10;

An ion exchange resin (30) for adsorbing radioactive ions dissolved in the form of ions in the decontamination liquid passed through the particulate filter (20); And

The decontamination liquid discharged from the decontamination tank 10 includes a circulation pump 50 which is operated to enter the decontamination tank 10 again through a series of processes.

Accordingly, it can be safely decontaminated within a short time without damaging the object to be salted during decontamination, it is possible to reduce the amount of secondary waste generated during decontamination.

Description

Ultrasonic decontamination machine {Ultrasonic decontamination system}

The present invention relates to an ultrasonic decontamination apparatus for decontaminating an object contaminated with radioactive material using ultrasonic waves, and more particularly, to an ultrasonic decontamination apparatus having a high decontamination efficiency and reducing generation of secondary wastes.

In general, there are two methods of decontamination of radioactive pollution used in nuclear power plants and related facilities. One is physical decontamination using friction and the other is chemical decontamination using chemicals.

The physical decontamination method is a decontamination method by washing with friction using a brush or a scrubbing brush, and it is possible to remove only the glassy contaminants present on the surface of metallic radioactive waste, and to expect no effect in case of sticking contamination. it's difficult. Accordingly, when the decontamination object has a complicated shape, the decontamination is abandoned, and since the decontamination worker directly handles radioactive contaminants, radiation exposure due to decontamination is also accompanied. In addition, the physical decontamination method by friction has a problem that the decontamination is easily damaged by physical friction, the decontamination efficiency according to the surface state and shape of the decontamination and the chemical and physical state of the radioactive pollutant that is the source of contamination. There is a big difference.

Chemical decontamination is a method of decontamination using a decontamination solution combined with various chemicals. The chemical decontamination dissolves and removes a metal oxide film contaminated with radioactive material and deposited. This chemical decontamination method takes a long time to operate the radioactive decontamination system because of the high pollution level of liquid waste generated after decontamination, which increases the overall pollution level of the low level liquid waste in the liquid waste treatment system. Occurs when saturation occurs.

In addition, since the amount of radioactive waste generated after chemical decontamination is very large to increase the disposal cost, it is a factor that greatly lowers the economic efficiency of decontamination. Furthermore, the decontamination waste solution after the completion of chemical decontamination passes through the ion exchange resin layer to be deionized. As a result, the discharged waste ion exchange resin is disposed of by immobilization medium such as polymer material, asphalt and cement, or dehydrated and dried by SRDS (Spent Resin Drying System). Rather than the amount of ion exchange resin used to remove contaminants is enormous.

As a result, the amount of radioactive waste to be finally disposed to immobilize the used waste resin also increases proportionally, resulting in an increase in radioactive waste treatment costs.

The present invention has been made in consideration of the above-described conventional problems, and provides an ultrasonic decontamination apparatus that can be safely decontaminated within a short time without damaging the object to be contaminated and the amount of secondary waste generated during decontamination can be suppressed. .

1 is a schematic view of the ultrasonic decontamination machine according to the present invention.

2 is a cross-sectional view taken along the line II-II of FIG.

3 is a cross-sectional view taken along line III-III of FIG. 1;

<Explanation of symbols for the main parts of the drawings>

10. Decontamination tank 11 ... Vibration element

20 ... Particulate filter 30 ... Ion exchange resin

40 ... Differential pressure gauge 50 ... Circulation pump

60 ... Return valve 100 ... Bypass

In order to achieve the above object, the present invention, a decontamination tank having a plurality of vibration elements for generating a cavitation phenomenon in the decontamination solution;

A particulate filter for filtering fine radioactive particles in the decontamination solution;

An ion exchange resin to which radioactive ions dissolved in the form of ions in the decontamination solution are adsorbed; and

The decontamination liquid discharged from the decontamination tank is characterized in that it comprises a circulating pump which is operated to enter the decontamination tank again through a series of processes.

In addition, the inlet and outlet path of the decontamination tank, and the reverse circulation prevention valve for preventing the back flow of the decontamination liquid circulating is installed behind the ion exchange resin may be further included.

In addition, it is preferable to further include a bypass path formed between the ion exchange resin and the particulate filter so that selective flow of the decontamination liquid into the ion exchange resin is achieved.

In addition, the vibrating element is preferably equally installed in the entire direction of the decontamination tank so that uniform ultrasonic waves are emitted to the decontamination solution.

In addition, one side of the particulate filter may be provided with a differential pressure gauge for informing the replacement time of the particulate filter.

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

As shown in FIG. 1, the ultrasonic decontamination machine of the present invention includes a decontamination tank 10 having a plurality of vibration elements 11, a particulate filter 20 for filtering fine radioactive particles in the decontamination solution, and a decontamination solution. It consists of an ion exchange resin 30 which adsorbs the radioactive ions dissolved in it, and a circulation pump 50 which circulates the decontamination liquid.

Prior to the detailed description of the present invention, the decontamination principle of the ultrasonic decontamination apparatus according to the present invention is that ultrasonic waves generated from a vibrating element installed in the decontamination tank generate cavitation in the decontamination tank so that they are attached to the entire surface of the contaminant in the decontamination tank. To keep the contaminants out.

Cavitation is a phenomenon in which the contraction and expansion occur alternately due to the vibration of molecules when ultrasonic waves, which are negative vibrations with strong energy, are radiated to the medium of liquid at a high frequency (20 kHz or more) that is inaudible to the human ear. It propagates, and the wave breaks cohesive force between molecules, and microcavity occurs. In other words, when the ultrasonic wave is radiated to the medium of liquid, ultrasonic vibration with strong energy is generated. The ultrasonic vibration causes the molecules of the medium to vibrate, causing contraction and expansion alternately. The cohesive force of is broken and numerous fine cavities are generated. This phenomenon is called cavitation, and the contaminants of the blood can be removed by the powerful energy released by the cavity exploding.

As shown in Figures 2 and 3, the decontamination tank 10 constituting the present invention is a decontamination tank body 10b having an open top, and an upper cover 10a covering the upper portion of the decontamination tank body 10b. It consists of. In addition, an inflow path 14 and a discharge path 15 for inflow and outflow of the decontamination liquid in the decontamination tank 10 are formed at one side of the decontamination tank body 10b, respectively.

The decontamination tank body 10b has an accommodating part in which the decontamination solution is stored in the inner center, and the upper cover 10a has an openable structure so that the decontamination solution stored in the accommodating part is not discharged to the outside. The watertight sealing member 13 is attached to the contact surface of the cover 10a.

In addition, the salt rest holder 12 is installed in the center of the receiving part. The cradle 12 is fixed to the inner wall surface on both sides so as to be located in the center of the receiving portion is made of a hemispherical mesh type so that the chlorine can be evenly contacted with the decontamination solution.

In addition, the decontamination tank 10 is provided with a plurality of vibration elements 11 for generating ultrasonic waves toward the object to be immersed in the decontamination tank 10.

The vibrating elements 11 are equally installed with respect to the entire direction of the decontamination tank 10 so that uniform ultrasonic waves are radiated to the decontamination solution. In this embodiment, the decontamination tank 10 is installed uniformly in the up, down, left, right, front and rear directions, respectively.

In addition, it is preferable that each vibrating element 11 is installed close to the same distance from the salt to be sprayed, respectively.

In addition, the radioactive particles diffused during decontamination are mainly deposited on the protrusion of the wall of the receiving portion, it is preferable that the vibration element 11 is installed outside the receiving portion so that such a protrusion is not formed.

On the other hand, since the configuration in which the ultrasonic wave is generated from the vibrating element 11 is already widely known, a detailed description thereof will be omitted.

The particulate filter 20 connected to the discharge passage 15 of the decontamination tank 10 has a filter layer for filtering fine radioactive particles therein. Both sides of the particulate filter 20 is formed with an inflow path through which the decontamination liquid discharged from the discharge path of the decontamination tank 10 flows, and a discharge path through which the decontamination liquid passing through the filter is discharged to the outside. The first connection pipe 70 is connected to the decontamination tank 10 in the inflow path, and the second connection pipe 80 is connected to the ion exchange resin 30 in the discharge path.

In addition, a differential pressure gauge 40 is installed at one side of the particulate filter 20 to detect a pressure difference between the inflow path and the discharge path and to inform the filter replacement time.

The ion exchange resin 30 has a resin layer that adsorbs radioactive ions dissolved in the form of ions in the decontamination liquid that has passed through the particulate filter 20 inside. The ion exchange resin 30 has an inflow path coupled to the second connection pipe 80 and a discharge path through which the decontamination liquid passing through the resin layer is discharged to the outside. The discharge passage is connected to the third connecting pipe 90 is connected to the circulation pump 50.

The circulation pump 50 is connected to the third connecting pipe 90 and the outlet side is connected to the decontamination tank so that the decontamination liquid discharged from the decontamination tank 10 flows back into the decontamination tank 10 through a series of processes. It is connected to the inflow path 14 of 10).

On the other hand, the second connecting pipe (80) connecting the particulate filter (20) and the ion exchange resin (30) bypasses the ion exchange resin (30) so that the selective flow of the decontamination solution is made to the third connecting pipe (90) Bypass 100 is connected to the installation. The bypass passage 100 is provided with a valve that enables selective operation of the bypass passage 100.

In addition, the inflow path 14 and the discharge path 15 of the decontamination tank 10 and the third connecting pipe 90 are provided with a reverse circulation prevention valve 60 for preventing the reverse flow of the decontamination liquid circulating.

Referring to the operation of the ultrasonic decontamination apparatus according to an embodiment of the present invention made of such a configuration as follows.

First, the user puts the salt to be decontaminated on the salt holder cradle 12 of the salt tank 10 filled with the salt solution and closes the top cover 10 a to seal the salt tank 10 and then the circulation pump ( 50) and the vibrating element 11 are sequentially operated.

The decontamination liquid in the decontamination tank 10 starts circulation by the circulation pump 50, and the ultrasonic waves generated from the vibrating element 11 are transmitted to the decontamination liquid. In general, the ultrasonic waves generated from the vibrating element 11 are essentially the same as the sound waves in the audible range, but because the frequency is high and the wavelength is short, very strong vibrations are generated. Therefore, each vibrating element 11 emits ultrasonic waves only on one side of the object to be treated. In the decontamination tank 10 of the present invention, since the vibrating element 11 is installed evenly in the up, down, left, right, front and back directions, ultrasonic waves are evenly radiated in all directions of the object to be removed. Therefore, since only one decontamination operation removes contaminants on the surface without damaging the object, rapid and safe decontamination is achieved.

In addition, the decontamination holder 12 in the decontamination tank 10 is installed in a hemispherical mesh type so that the front surface can be in contact with the decontamination solution, and is fixed to the center of the receiving portion uniformly from each vibrating element (11) Can be decontaminated for a century.

Thereafter, when ultrasonic waves generated from the vibrating element 11 installed in the decontamination tank 10 generate cavitation in the decontamination tank 10, the radioactive particles and the ionizing material, which are the contaminants, are separated from the surface of the decontamination due to the impact. . The radioactive particles and the ionizing material are discharged to the outside through the discharge path 15 together with the decontamination liquid, and are caught and removed by the particulate filter 20 and the ion exchange resin 30. That is, the decontamination solution flowing into the inside of the particulate filter 20 from the decontamination tank 10 through the first connecting pipe 70 passes through the filter layer. In this process, the radioactive particles in the decontamination solution are filtered out. The decontamination solution passing through the filter layer is introduced into the ion exchange resin 30 through the second connecting pipe 80, and the ionizing material in the decontamination solution is filtered out in the course of passing through the ion exchange resin 30.

Through the above process, the decontamination liquid is purified by a low pollution step, and is recycled by being supplied again through the inflow path 14 of the decontamination tank 10.

As described above, since the ultrasonic decontamination machine of the present invention is decontaminated by ultrasonic waves, it is possible to minimize the generation of chemicals generated after decontamination by chemical methods and secondary wastes for treating the chemicals as in the prior art. Can be.

On the other hand, in the bypass passage 100 installed in the second connecting pipe 80 to decontaminate by adding a surfactant to the decontamination solution in order to increase the decontamination efficiency, due to the ionic component of the surfactant itself is excessive in the ion exchange resin (30) Since the ion component may be deposited and the ion treatment efficiency of the ion exchange resin 30 may be lowered, in order to prevent such a phenomenon, the decontamination solution is bypassed so as not to flow into the ion exchange resin 30 side. Use of this bypass 100 allows selective operation according to the decontamination method.

In addition, the inflow path 14 and the discharge path 15 of the decontamination tank 10 and the reverse circulation prevention valve 60 respectively installed in the third connecting pipe 90 may be formed due to poor circulation of the decontamination liquid. Prevent backflow of salt solution.

In addition, the differential pressure gauge 40 installed on one side of the particulate filter 20 detects the pressure of the particulate filter 20 and informs the replacement time of the particulate filter 20 when the pressure difference is greater than or equal to a predetermined pressure, so that smooth decontamination is achieved. do.

According to the ultrasonic decontamination machine according to the present invention configured as described above, it is possible to quickly and safely decontaminate contaminants on the surface without damaging the object to be decontaminated, and to remove unnecessary secondary wastes by purifying and recycling the radioactive particles and ionization materials removed during decontamination. Economics can be saved by reducing the cost of treating radioactive waste while suppressing the occurrence of

Although the present invention has been illustrated and described in connection with specific embodiments, the present invention may be variously modified and changed without departing from the spirit or the field of the present invention provided by the following utility model registration claims. It should also be included in the scope of the present invention.

Claims (5)

Decontamination tank 10 having a plurality of vibration elements 11 for generating a cavitation phenomenon in the decontamination solution; A particulate filter 20 for filtering fine radioactive particles contained in the decontamination liquid discharged from the decontamination tank 10; An ion exchange resin (30) for adsorbing radioactive ions dissolved in the form of ions in the decontamination liquid passed through the particulate filter (20); And Ultrasonic decontamination apparatus comprising a circulating pump (50) which is operated so that the decontamination liquid discharged from the decontamination tank (10) flows back into the decontamination tank (10) through a series of processes. The method of claim 1, The vibrating element (11) is an ultrasonic decontamination unit, characterized in that it is installed evenly with respect to the entire direction of the decontamination tank (10) so that uniform ultrasonic waves are emitted to the decontamination solution. The method of claim 1, One side of the particulate filter 20, the ultrasonic desalter, characterized in that the differential pressure gauge 40 is provided to inform the replacement time of the particulate filter (20). The method of claim 1, An inlet 14 and outlet 15 of the decontamination tank 10 and a reverse circulation prevention valve 60 for preventing the backflow of the decontamination liquid circulating in the rear of the ion exchange resin 30 are further installed. Ultrasonic decontamination machine. The method of claim 1, Ultrasonic decontamination unit is provided between the ion exchange resin and the particulate filter 20 is further provided with a bypass passage (100) for the selective introduction of the decontamination liquid to the ion exchange resin (30).