Radioactive material processing equipment and nuclear reactor facilities

Abstract

To provide a radioactive material treatment device capable of suppressing leakage of a radioactive material to the outside, and a reactor facility.SOLUTION: A radioactive material treatment device for treating gas containing steam and radioactive materials discharged from a reactor containment vessel comprises a containment building that stores the reactor containment vessel in an internal space airtightly isolated from the outside, and a cooling unit that cools the atmosphere of the internal space.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a radioactive material treatment device and a nuclear reactor facility. [Background technology]

[0002] Patent Document 1 discloses a nuclear reactor facility equipped with a filter vent. The filter vent removes iodine and radioactive particles from gas discharged from the reactor containment vessel. The gas from which iodine and radioactive particles have been removed is discharged into the atmosphere. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5898018 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, the gas discharged into the atmosphere from the filter vent contains trace amounts of radioactive materials such as Xe, Kr, etc. However, it is desirable that these radioactive materials not be discharged into the atmosphere.

[0005] The present disclosure has been made in consideration of the above circumstances, and provides a radioactive material treatment device and nuclear reactor facility that can suppress leakage of radioactive materials to the outside. [Means for solving the problem]

[0006] In order to solve the above problems, The radioactive material treatment device is a radioactive material treatment device that treats steam and gas containing radioactive materials discharged from a reactor containment vessel, and includes: a containment building that stores the reactor containment vessel within an internal space that is airtightly isolated from the outside; a cooling unit that cools the atmosphere of the internal space; a water source that is provided outside the containment building and stores cooling water; a supply line that supplies the cooling water from the water source to the cooling unit; a drainage device that discharges the gas condensed by the cooling water together with the cooling water as circulating water to the outside of the containment building; a return line that returns the circulating water from the drainage device to the supply line as the cooling water; and a demineralization tower that is provided midway through the supply line outside the containment building and removes the radioactive materials contained in the cooling water, and the cooling unit has a spray device that sprays the cooling water from above the reactor containment vessel in the internal space.

[0008] A nuclear reactor facility according to a third aspect of the present disclosure includes the radioactive material treatment device and the reactor containment vessel. Effect of the Invention

[0009] According to the present disclosure, it is possible to provide a radioactive material treatment device and nuclear reactor facility that are capable of suppressing leakage of radioactive materials to the outside. [Brief description of the drawings]

[0010] [Figure 1] 1 is a cross-sectional view showing an overall schematic configuration of a nuclear reactor facility according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, the nuclear reactor facility according to this embodiment will be described with reference to the drawings.

[0012] (Nuclear reactor equipment) The nuclear reactor facility is located on the site of a nuclear power plant. As shown in FIG. 1, the nuclear reactor facility 1 includes a nuclear reactor 10, a reactor containment vessel 20, and a radioactive material treatment device 5.

[0013] (nuclear reactor) The nuclear reactor 10 is a pressurized water reactor (PWR) that uses uranium oxide or the like as nuclear fuel. The nuclear reactor 10 heats a primary coolant (light water) by thermal energy of nuclear fission caused by the nuclear fuel in the reactor core.

[0014] The heated primary coolant heats and boils the secondary coolant (light water) in a steam generator (not shown), generating high-temperature, high-pressure steam. This steam generated in the steam generator (not shown) in the reactor 10 is sent to a steam turbine (not shown) provided, for example, outside the reactor facility 1 via a steam line (not shown). The steam introduced into the steam turbine rotates the turbine of the steam turbine. The rotation of this turbine drives a generator (not shown) to generate electricity.

[0015] (Reactor Containment Vessel) The reactor containment vessel 20 is a pressure-resistant vessel that contains the reactor 10 and also keeps inside the reactor containment vessel 20 gas V containing radioactive materials in the event of an emergency. The reactor containment vessel 20 is made of materials such as steel and concrete. The gas V inside the reactor containment vessel 20 contains steam as a condensable gas, radioactive materials, and non-condensable gas.

[0016] The reactor containment vessel 20 includes a containment vessel main body 21 and a vent device 22 . The containment vessel main body 21 contains the reactor 10, water injection equipment (not shown) for supplying water from the outside, and the like.

[0017] The vent device 22 is a device that discharges the gas V in the containment vessel body 21 to the outside in order to prevent the pressure in the containment vessel body 21 from reaching its withstand pressure limit due to a rise in pressure in the case where gas V containing radioactive materials is generated in the containment vessel body 21 in an emergency. The vent device 22 is provided in the containment vessel body 21. The vent device 22 has a vent pipe 22a and a vent valve 22b.

[0018] The vent pipe 22a is a pipe that connects the inside and outside of the containment vessel main body 21. The vent valve 22b is provided on the vent pipe 22a. The vent valve 22b is normally closed. For example, the vent valve 22b is opened when the pressure inside the containment vessel main body 21 reaches or exceeds a preset threshold value. This allows a large amount of gas V generated inside the containment vessel main body 21 to be discharged into the internal space R of the containment building 30 via the vent pipe 22a.

[0019] (Radioactive Material Treatment Equipment) The radioactive material treatment device 5 is a device that treats gas V containing radioactive materials discharged from the reactor containment vessel 20. The radioactive material treatment device 5 includes a containment building 30, a cooling section 40, a water source 100, a supply line 60, a drainage device 50, a return line 61, a demineralization tower 70, a cooler 80, a pump 90, and a bypass line 62.

[0020] (Storage building) The containment building 30 is a reactor building that contains the reactor containment vessel 20. The containment building 30 forms an internal space R that is airtightly isolated from the outside, and contains the reactor containment vessel 20 in the internal space R. The containment building 30 retains the gas V discharged from inside the containment vessel main body 21 via the vent device 22 within the space.

[0021] (cooling section) The cooling unit 40 is a device that cools the atmosphere in the internal space R. The cooling unit 40 is provided above the reactor containment vessel 20 in the internal space R in the containment building 30. The cooling unit 40 has a spray device 41 that sprays cooling water W supplied from outside the containment building 30 from above the reactor containment vessel 20.

[0022] The spray device 41 is a spray ring having a ring portion 41a and a spray nozzle 41b. The ring portion 41a is a pipe through which the cooling water W flows, and is provided over the entire ceiling wall portion of the containment building 30. A plurality of spray nozzles 41b are provided at equal intervals on the ring portion 41a, and spray the cooling water W flowing inside the ring portion 41a downward. The cooling water W sprayed by the spray nozzles 41b falls while spreading in the internal space R. Therefore, the cooling portion 40 can distribute the cooling water W almost evenly throughout the internal space R. The ring portion 41a may be provided over the entire side wall portion of the containment building 30.

[0023] Among the components of the gas V discharged from the containment vessel main body 21 into the internal space R via the vent device 22, for example, condensable gas such as steam is cooled and condensed by heat exchange with the cooling water W sprayed by the cooling unit 40. Also, non-condensable gas is contracted by heat exchange with the cooling water W sprayed by the cooling unit 40. This makes it possible to maintain the pressure in the internal space R at a pressure that can sufficiently reduce leakage of the gas V from the containment building 30. The cooling water W, which has been heat exchanged with the gas V discharged into the internal space R and has increased in temperature, accumulates at the bottom of the containment building 30. Some of the condensed radioactive materials are dissolved in this cooling water W that accumulates at the bottom of the containment building.

[0024] (water source) The water source 100 is a fuel replacement water tank provided outside the containment building 30. The water source 100 stores cooling water W therein. The cooling water W stored in the water source 100 in this embodiment is used as emergency water for the cooling unit 40 to cool the internal space R.

[0025] (Supply Line) The supply line 60 is a pipe that supplies the cooling water W from the water source 100 to the cooling unit 40. One end of the supply line 60 is connected to the water source 100. The other end of the supply line 60 is connected to the cooling unit 40. This allows the cooling water W stored in the water source 100 to flow through the inside of the supply line 60.

[0026] (Drainage device) The drainage device 50 is a device that exchanges heat with the gas V discharged into the internal space R and discharges the cooling water W, whose temperature has increased, as circulating water to the outside of the containment building 30. The drainage device 50 is a sump pit for drainage provided below the reactor containment vessel 20 in the internal space R of the containment building 30.

[0027] (Return line) The return line 61 is a pipe that sends the circulating water discharged from the drainage device 50 to the supply line 60. One end of the return line 61 is connected to the drainage device 50. The other end of the return line 61 is connected to the middle of the supply pipe outside the containment building 30. As a result, the circulating water discharged from the drainage device 50 is guided to the supply line 60 via the return line 61 and merges with the cooling water W flowing through the supply line 60.

[0028] That is, the return line 61 returns the circulating water to the supply line 60 as the cooling water W. Therefore, the cooling water W sprayed into the internal space R by the cooling unit 40 is guided again as the cooling water W to the cooling unit 40 via the supply line 60.

[0029] (Demineralization tower) The demineralization tower 70 is provided midway through the supply line 60 outside the containment building 30, and is a device that removes the condensed portion of the gas V discharged into the internal space R and the radioactive materials dissolved in the cooling water W. The demineralization tower 70 adsorbs and removes a portion of the ionized radioactive materials dissolved in the cooling water W. Therefore, the cooling section 40 is introduced with the cooling water W having reduced radioactive materials.

[0030] (cooler) The cooler 80 is provided midway along the supply line 60 outside the containment building 30, and is a device for cooling the cooling water W. The cooler 80 is provided in the supply line 60 between the demineralization tower 70 and the connection portion where the return line 61 and the supply line 60 are connected.

[0031] (pump) The pump 90 is a device that is provided midway through the supply line 60 outside the containment building 30 and pressure-feeds the cooling water W flowing through the supply line 60 to the cooling section 40. The pump 90 is provided in the supply line 60 between the cooler 80 and the connection portion where the return line 61 and the supply line 60 are connected.

[0032] (Bypass line) The bypass line 62 is a pipe that changes the flow path of the cooling water W flowing through the supply line 60 midway through the supply line 60 outside the containment building 30. One end of the bypass line 62 is connected to the supply line 60 between the demineralizer 70 and the cooler 80. The other end of the bypass line 62 is connected to the supply line 60 between the demineralizer 70 and the cooling section 40. A bypass valve 22c is provided midway through the bypass line 62.

[0033] The bypass valve 22c is normally closed. The bypass valve 22c is opened when, for example, clogging occurs in the adsorption device of the demineralization tower 70 and the cooling water W does not flow sufficiently inside the supply line 60 downstream of the demineralization tower 70. This allows the cooling unit 40 to spray a sufficient amount of cooling water W into the internal space R.

[0034] (Action and effect) In the radioactive material treatment device 5 of the above embodiment, the cooling unit 40 cools the atmosphere of the internal space R airtightly isolated from the outside of the containment building 30, so that condensable steam and a part of the radioactive material contained in the gas V discharged from the reactor containment vessel 20 are condensed. In addition, the non-condensable gas is contracted by heat exchange with the cooling water W sprayed by the cooling unit 40. This makes it possible to maintain the pressure of the internal space R at a pressure that can sufficiently reduce the leakage of the gas V from the containment building 30. In other words, the radioactive material is confined within the containment building 30, and the internal space R can be prevented from becoming high pressure. Therefore, for example, even if the gas V containing a large amount of radioactive material is generated in the containment vessel main body 21 during an emergency, it is possible to prevent the internal pressure of the reactor containment vessel 20 from increasing and to suppress the leakage of the radioactive material to the outside.

[0035] In the radioactive material treatment device 5 of the above embodiment, the cooling water W is supplied to the cooling unit 40 from the water source 100 via the supply line 60. The spray device 41 of the cooling unit 40 sprays the cooling water W from above the reactor containment vessel 20 in the internal space R. This makes it possible to achieve the above-mentioned effects with a more specific configuration, and at the same time, a portion of the condensed radioactive material dissolves in the cooling water W. Then, the cooling water W in which the radioactive material is dissolved falls to the bottom of the internal space R and accumulates. Therefore, the cooling water W in which the radioactive material is dissolved can be efficiently collected.

[0036] Furthermore, in the radioactive material treatment device 5 of the above embodiment, the drainage device 50 drains the cooling water W in which the radioactive material is dissolved as circulating water to the outside of the containment building 30. The drained circulating water merges with the cooling water W flowing in the supply line 60 via the return line 61, and then a portion of the radioactive material is removed in the demineralization tower 70. This allows the cooling unit 40 to reuse the circulating water as the cooling water W, and reduces the radioactive material in the internal space R. Therefore, an increase in the concentration of the radioactive material in the internal space R can be mitigated.

[0037] Moreover, in the radioactive material treatment apparatus 5 of the above embodiment, the cooler 80 lowers the temperature of the cooling water W sprayed by the cooling unit 40. This makes it possible to enhance the condensation effect of the radioactive material in the containment building 30.

[0038] Moreover, in the radioactive material treatment device 5 of the above embodiment, the demineralization tower 70, the cooler 80, the pump 90, and the bypass valve 22c are provided outside the containment building 30. This allows workers to safely perform maintenance on the demineralization tower 70, the cooler 80, the pump 90, and the bypass valve 22c while maintaining the airtightness of the containment building 30. Furthermore, since the pump 90 and the bypass valve 22c are not exposed to a high-temperature, high-pressure atmosphere, the operating environment of the pump 90 and the bypass valve 22c can be alleviated.

[0039] Moreover, in the nuclear reactor facility 1 of the above embodiment, leakage of radioactive materials to the outside can be suppressed.

[0040] [Other embodiments] Although the embodiments of the present disclosure have been described above in detail with reference to the drawings, the specific configuration is not limited to the configuration of the embodiment, and addition, omission, substitution, and other modifications of the configuration are possible within the scope of the gist of the present disclosure. Furthermore, the present disclosure is not limited to the embodiments, but is limited only by the claims.

[0041] Moreover, the cooling unit 40 may further include a packaged air conditioner or the like that cools the atmosphere in the internal space R. This allows the atmosphere in the internal space R to be further cooled, and the condensation effect of the radioactive materials in the containment building 30 can be further improved.

[0042] Further, in the above embodiment, a pressurized water reactor (PWR) is shown as the reactor 10, but the reactor 10 is not limited to a pressurized water reactor, and may be a boiling water reactor (BWR) or the like.

[0043] [Note] The radioactive material treatment device and the nuclear reactor facility described in the embodiments can be understood, for example, as follows.

[0044] (1) The radioactive material treatment device 5 according to the first embodiment is a radioactive material treatment device 5 that treats steam and gas V containing radioactive materials discharged from a reactor containment vessel 20, and includes a containment building 30 that stores the reactor containment vessel 20 within an internal space R that is airtightly isolated from the outside, and a cooling unit 40 that cools the atmosphere of the internal space R.

[0045] According to the above configuration, the cooling unit 40 cools the atmosphere of the internal space R that is airtightly isolated from the outside of the containment building 30, so that the condensable steam and some of the radioactive materials contained in the gas V discharged from the reactor containment vessel 20 are condensed. In addition, the non-condensable gas contracts, and the pressure in the internal space R can be maintained at a pressure that can sufficiently reduce leakage of the gas V from the containment building 30. This allows the radioactive materials to be confined within the containment building 30, and the internal space R to be prevented from becoming highly pressurized.

[0046] (2) A radioactive material treatment device 5 according to a second aspect is the radioactive material treatment device 5 of (1), which is provided outside the containment building 30 and further includes a water source 100 for storing cooling water W and a supply line 60 for supplying the cooling water W from the water source 100 to the cooling section 40, and the cooling section 40 may have a spray device 41 for spraying the cooling water W from above the reactor containment vessel 20 in the internal space R.

[0047] According to the above configuration, cooling water W is supplied to the cooling unit 40 from the water source 100 via the supply line 60. The spray device 41 of the cooling unit 40 sprays the cooling water W from above the reactor containment vessel 20 in the internal space R. This makes it possible to achieve the above-mentioned effects with a more specific configuration, and at the same time, a portion of the condensed radioactive material dissolves in the cooling water W. Then, the cooling water dissolved in the cooling water W falls to the bottom of the internal space R and accumulates there.

[0048] (3) A radioactive material treatment device 5 according to a third aspect is the radioactive material treatment device 5 of (2), and may further include a drainage device 50 that discharges the gas V condensed by the cooling water W together with the cooling water W to the outside of the containment building 30 as circulating water, a return line 61 that returns the circulating water from the drainage device 50 to the supply line 60 as the cooling water W, and a demineralization tower 70 that is provided midway on the supply line 60 outside the containment building 30 and removes a portion of the radioactive material contained in the cooling water W.

[0049] According to the above configuration, the drainage device 50 drains the cooling water W in which radioactive materials are dissolved as circulating water to the outside of the containment building 30. The drained circulating water merges with the cooling water W flowing in the supply line 60 via the return line 61, and then a portion of the radioactive materials is removed in the demineralization tower 70. This allows the cooling section 40 to reuse the circulating water as cooling water W, and also mitigates an increase in the concentration of radioactive materials in the internal space R.

[0050] (4) A radioactive material treatment device 5 according to a fourth aspect is the radioactive material treatment device 5 of (2) or (3), and may further include a cooler 80 that is provided midway along the supply line 60 outside the containment building 30 and cools the cooling water W.

[0051] According to the above configuration, the cooler 80 lowers the temperature of the cooling water W sprayed by the cooling unit 40. This makes it possible to enhance the condensation effect of the condensable gas and the contraction effect of the non-condensable gas in the containment building 30.

[0052] (5) A radioactive material treatment device 5 according to a fifth aspect is a radioactive material treatment device 5 that treats steam and gas V containing radioactive materials discharged from a reactor containment vessel 20, and is provided with a cooling unit 40 that hermetically isolates the reactor containment vessel 20 from the outside and cools the atmosphere in an internal space R between the reactor containment vessel 20 and a containment building 30 that stores the reactor containment vessel 20.

[0053] (6) The nuclear reactor facility 1 according to a sixth aspect may include the radioactive material processing device 5 according to any one of (1) to (5) and the reactor containment vessel 20.

[0054] According to the above configuration, leakage of radioactive materials to the outside can be suppressed. [Explanation of symbols]

[0055] 1...nuclear reactor facility 5...radioactive material treatment device 10...nuclear reactor 20...nuclear reactor containment vessel 21...containment vessel body 22...vent device 22a...vent pipe 22b...vent valve 22c...bypass valve 30...containment building 40...cooling section 41...spray device 41a...ring section 41b...spray nozzle 50...drainage device 60...supply line 61...return line 62...bypass line 70...desalting tower 80...cooler 90...pump 100...water source R...internal space V...gas W...cooling water

Claims

1. A radioactive material treatment device for treating steam and gas containing radioactive materials discharged from a nuclear reactor containment vessel, a containment building that contains the reactor containment vessel in an internal space that is airtightly isolated from the outside; A cooling unit that cools the atmosphere of the internal space; A water source provided outside the containment building and configured to store cooling water; a supply line for supplying the cooling water from the water source to the cooling section; a drainage device that discharges the gas condensed by the cooling water together with the cooling water to the outside of the containment building as circulating water; a return line for returning the circulating water from the drainage device to the supply line as the cooling water; a demineralization tower provided in the supply line outside the containment building and configured to remove the radioactive materials contained in the cooling water; Equipped with The cooling unit is a radioactive material treatment device having a spray device that sprays the cooling water from above the reactor containment vessel in the internal space.

2. The radioactive material treatment apparatus according to claim 1 , further comprising a cooler provided midway through the supply line outside the containment building to cool the cooling water.

3. The radioactive material treatment device according to claim 1 or 2, The reactor containment vessel; A nuclear reactor facility equipped with:

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