Dismantling and decontamination system and method of bioprotective concrete of PWR type nuclear power plant

Abstract

A dismantling and decontamination system of biodegradable concrete of a nuclear power plant according to an exemplary embodiment includes: a dismantling device for dismantling an in-core instrument installed under biodegradable concrete to form a lower penetrated part of the biodegradable concrete; a decontamination device inserted inside the biodegradable concrete for decontaminating radioactive waste of the inner wall of the biodegradable concrete; a waste receiving device movable through the lower penetrated part of the biodegradable concrete; and a blocking device for blocking the upper opening of the biodegradable concrete to block an outflow of the radioactive dust.

Claims

1. A dismantling and decontamination system for dismantling and decontaminating bioprotective concrete of a nuclear power plant, comprising: a dismantling device configured to dismantle an in-core instrument to form a penetrated part of the bioprotective concrete, wherein the in-core instrument is installed within the bioprotective concrete at a lower part of the bioprotective concrete, and wherein the penetrated part is formed in the lower part of the bioprotective concrete; a decontamination device configured to be inserted inside of an interior space of the bioprotective concrete for decontaminating radioactive waste of an inner wall of the bioprotective concrete forming the interior space, wherein the decontamination device, in its entirety, is inserted inside of the interior space of the bioprotective concrete; a waste receiving device configured to move into the interior space of the bioprotective concrete through the penetrated part of the bioprotective concrete; and a blocking device configured to contact an upper surface of the bioprotective concrete and block an upper opening of the interior space of the bioprotective concrete to block an outflow of radioactive dust.

2. The dismantling and decontamination system of the bioprotective concrete of the nuclear power plant of claim 1, wherein the waste receiving device includes: a receiving unit receiving the radioactive waste; and a moving unit for moving the receiving unit.

3. The dismantling and decontamination system of the bioprotective concrete of the nuclear power plant of claim 2, wherein the area of the receiving unit is adjustable from a first area able to pass through the penetrated part to a second area greater than the first area and smaller than a cross-sectional area of the interior space of the bioprotective concrete.

4. The dismantling and decontamination system of the bioprotective concrete of the nuclear power plant of claim 1, wherein the decontamination device includes a hammer or a scabbler.

5. The dismantling and decontamination system of the bioprotective concrete of the nuclear power plant of claim 1, wherein the dust blocking device includes a tent or a shield.

Description

DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic diagram of a dismantling and decontamination system of bioprotective concrete of a nuclear power plant according to an exemplary embodiment.

(2) FIG. 2 is a top plan view showing a state in which a size of a receiving unit of a waste receiving device of FIG. 1 is changed inside bioprotective concrete.

(3) FIG. 3 is a flowchart of a decontamination and dismantling method of bioprotective concrete of a nuclear power plant according to an exemplary embodiment.

(4) FIG. 4 is a view showing a step before dismantling bioprotective concrete of a nuclear power plant according to an exemplary embodiment.

MODE FOR INVENTION

(5) The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

(6) In order to clearly explain the present invention, portions that are not directly related to the present invention are omitted, and the same reference numerals are attached to the same or similar constituent elements through the entire specification.

(7) In addition, the size and thickness of each configuration shown in the drawings are arbitrarily shown for better understanding and ease of description, but the present invention is not limited thereto.

(8) In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. In the drawings, for better understanding and ease of description, the thicknesses of some layers and areas are exaggerated. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being on another element, it can be directly on the other element or intervening elements may also be present.

(9) In addition, unless explicitly described to the contrary, the word comprise, and variations such as comprises or comprising, will be understood to imply the inclusion of stated elements but not the exclusion of any other elements. Further, in the specification, the word on means positioning on or below the object portion, but does not essentially mean positioning on the upper side of the object portion based on a gravity direction.

(10) FIG. 1 is a schematic diagram of a dismantling and decontamination system of bioprotective concrete of a nuclear power plant according to an exemplary embodiment.

(11) As shown in FIG. 1, a dismantling and decontamination system of bioprotective concrete of a nuclear power plant according to an exemplary embodiment includes a dismantling device 5 dismantling an in-core instrument (ICI) 300 installed under bioprotective concrete 200, a decontamination device 10 decontaminating radioactive waste 1 of the inner wall of the bioprotective concrete 200, a waste receiving device 20 receiving the radioactive waste 1 decontaminated by the decontamination device 10, a dust blocking device 30 blocking radioactive dust 3 generated during the decontamination of the radioactive waste 1, and a dust collecting device 40 collecting the radioactive dust 3.

(12) The dismantling device 5 forms a lower penetrated part 210 under the bioprotective concrete 200 by dismantling the in-core instrument 300 installed from the lower part of the bioprotective concrete 200 to the inside of a nuclear reactor 100. The lower penetrated part 210 of the bioprotective concrete 200 is the space where the in-core instrument (ICI) 300 of the bioprotective concrete 200 was positioned. The in-core instrument 300 is a device to measure an output distribution and combustibility of a nuclear fuel inside the nuclear reactor and to measure an outlet temperature of the core of the nuclear reactor 100 by detecting neutrons generated during the nuclear fission reaction process of the nuclear reactor 100.

(13) The decontamination device 10 is put into the inside of the bioprotective concrete 200. The decontamination device 10 may include an inner wall hammer or a scabbler. The inner wall hammer hits the inner wall of the bioprotective concrete 200 to remove the radioactive waste 1 from the inner wall of the bioprotective concrete 200. Further, the scabbler scrapes the inner wall of the bioprotective concrete 200 to remove the radioactive waste 1 from the inner wall of the bioprotective concrete 200. In the present exemplary embodiment, the inner wall hammer or the scabbler has been described as an example of the decontamination device, but it is not limited thereto, and various devices are possible as long as it is a device for removing the radioactive waste 1 from the inner wall of the bioprotective concrete 200.

(14) The waste receiving device 20 may include a receiving unit 21 for receiving the radioactive waste 1, a receiving unit size adjusting unit 22 for adjusting the size of the receiving unit 21 and a moving unit 23 for moving the receiving unit 21.

(15) As shown in FIG. 2, the size of the receiving unit 21 is adjustable. When passing through the lower penetrated part 210, the size of the receiving unit 21 may be smaller than the diameter of the lower penetrated part 210 so that the receiving unit 21 may easily pass through the lower penetrated part 210. Further, when being disposed inside the bioprotective concrete 200, the size of the receiving unit 21 is expanded so that the receiving unit 21 may receive most of the radioactive waste 1 and may be smaller than the interior diameter of the bioprotective concrete 200.

(16) This waste receiving device 20 is movable through the lower penetrated part 210 of the bioprotective concrete 200. The lower penetrated part 210 of the bioprotective concrete 200 may be connected to the interior of the bioprotective concrete 200 where the decontamination device 10 is positioned. Thus, the waste receiving device 20 may be disposed under the decontamination device 10. Therefore, the waste receiving device 20 may easily accommodate the radioactive waste 1 separated from the inner wall of the bioprotective concrete 200 by the decontamination device 10.

(17) As described above, when the decontamination process of the bioprotective concrete 200 of the nuclear power plant is in progress, the waste receiving device 20 may be easily inserted and taken out from time to time by using the lower penetrated part 210 of the bioprotective concrete 200 without the need to take out the radioactive waste 1 of the inner wall of the bioprotective concrete 200 to an upper opening 220. Therefore, it is possible to shorten the decontamination process time of the inner wall of the bioprotective concrete 200.

(18) The dust blocking device 30 may block the upper opening 220 of the bioprotective concrete 200 to block the outflow of the radioactive dust 3. The dust blocking device 30 may include a tent or a shield. In the present exemplary embodiment, the tent or shield has been described as an example of the dust blocking device 30, but it is not limited thereto, and various devices for blocking the radioactive dust are possible. In addition, the dust blocking device 30 may further include a blocking adjusting unit for blocking or opening the upper opening 220 of the bioprotective concrete 200.

(19) In this way, when the decontamination and dismantling process of the inner wall of the bioprotective concrete 200 is performed using the lower penetrated part 210 of the bioprotective concrete 200, the upper opening 220 of the bioprotective concrete 200 is kept sealed by using the dust blocking device 30, thereby reducing worker exposure to the radioactive dust 3 and preventing the spread of the radioactive dust.

(20) The dust collecting device 40 is connected to the dust blocking device 30 and is disposed outside the bioprotective concrete 200. It is possible to secure a view inside the work part through the dust collecting device 40 using an exhaust fan.

(21) Meanwhile, the decontamination and dismantling method of the bioprotective concrete of the nuclear power plant according to an exemplary embodiment of the present invention is described in detail below with reference to drawings.

(22) FIG. 2 is a top plan view showing a state in which a size of a receiving unit of a waste receiving device of FIG. 1 is changed inside bioprotective concrete, and FIG. 3 is a flowchart of a decontamination and dismantling method of bioprotective concrete of a nuclear power plant according to an exemplary embodiment.

(23) As shown in FIG. 3 and FIG. 4, in the decontamination and dismantling method of the bioprotective concrete of the nuclear power plant according to an exemplary embodiment of the present invention, the in-core instrument 300 installed under the bioprotective concrete 200 is dismantled by using the dismantling device 5 to form the lower penetrated part 210 under the bioprotective concrete 200 (S10). Since the in-core instrument 300 is connected to the nuclear reactor 100 through a plurality of cables, etc., the cables may be separated from the nuclear reactor 100 to physically separate the in-core instrument 300 from the nuclear reactor 100.

(24) At this time, the nuclear reactor 100 disposed inside the bioprotective concrete 200 is also dismantled by using a nuclear reactor dismantling device 6.

(25) Next, as shown in FIG. 1 and FIG. 3, the decontamination device 10 is inserted inside the bioprotective concrete 200 to decontaminate the radioactive waste 1 of the inner wall of the bioprotective concrete 200 (S20). Further, the waste receiving device 20 is inserted into the interior of the bioprotective concrete 200 through the lower penetrated part 210 of the bioprotective concrete 200 (S30). At this time, the lower penetrated part 210 of the bioprotective concrete 200 may be connected to the interior of the bioprotective concrete 200. Thus, the waste receiving device 20 may be disposed under the decontamination device 10. Therefore, the waste receiving device 20 may easily accommodate the radioactive waste 1 of the inner wall of the bioprotective concrete 200 generated by the decontamination device 10.

(26) In addition, as shown in FIG. 1, the upper opening 220 of the bioprotective concrete 200 is blocked using the dust blocking device 30 to block the outflow of the radioactive dust 3. At this time, the radioactive dust 3 may be collected using the dust collecting device 40 connected to the dust blocking device 30.

(27) As described above, when the decontamination process of bioprotective concrete 200 of the nuclear power plant is in progress, since the waste receiving device 20 may be easily input and taken out from time to time by using the lower penetrated part 210 of the bioprotective concrete 200 without the need to carry out the radioactive waste 1 of the inner wall of the bioprotective concrete 200 to the upper opening 220 of the bioprotective concrete 200, the decontamination and dismantling process time of the inner wall of the bioprotective concrete 200 may be shortened.

(28) While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.