JP2022174697A - Use of tritiated water - Google Patents

Abstract

To provide a method of detoxifying tritiated water contained in radiation contaminated water of the Fukushima Daiich nuclear power plant after the catastrophic accident, PWR nuclear power plants, used nuclear fuel reprocessing plants, and the like.SOLUTION: A method disclosed herein comprises feeding tritiated water into a vertical prismatic cylinder, attaching insulation-coated electrodes on opposing surfaces of the cylinder, applying a DC voltage that changes every minute to break light water molecule clusters, and applying ultrasonic vibration from an upper part of the cylinder to force tritiated water molecules and heavy water molecules dispersed in the water to fall down and get together to make molecular aggregates, thereby producing concentrated water of heavy water and tritiated water. Ultrasonic vibration bubble crushing impact is excited to facilitate β-decay that eliminates neutron-rich instability.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method and apparatus for detoxifying radioactively contaminated water generated in nuclear power plants and spent nuclear fuel reprocessing plants. In particular, it corresponds to the disaster emergency of radioactive contaminated water at the Fukushima Daiichi Nuclear Power Plant after the explosion accident.

To detoxify the radioactive emitting atoms, first, the total number of radioactive emitting atoms is known. A becquerel unit is the number of atoms that generate radioactivity in an instant of one second. What we need to know is the number of all radioactive atoms that have not yet emitted radioactivity: Integrating radioactivity decaying with half-life T is 3.3 x l x T (provisional name: Shima's formula) . In the case of Fukushima tank-stored tritiated water, I=4 million B/L, half-life T=12.3 years=3.15×10 ⁷ seconds, 3.3×(4×10 ⁶ /L)×3. 15×10 ⁷ =4.2×10 ¹⁴ pieces/L. The number of molecules of light water is 3×10 ²⁵ /L, and the number of heavy water molecules of natural water is 4×10 ²¹ /L. Since the number of tritium water molecules is much smaller than that of light water and heavy water, it is necessary to concentrate the tritiated water more than 1,000 times.

Most of the radioactive waste atoms generated by uranium fission undergo β decay. Beta decay is a weak interaction of elementary particles, in which nuclear neutrons change into protons inside the nucleus, ejecting electrons. The atom changes because it has one more proton, but the total mass number of protons and neutrons remains the same. Atoms undergoing beta decay have an excess number of neutrons compared to protons. Therefore, it tries to stabilize by reducing neutrons. Therefore, β-decay, which converts neutrons into protons, can be forced to occur by <nuclear excitation> more easily than nuclear fusion reactions.

Bubbles are generated in the ultrasonic cleaner, and the bubbles are crushed by vibration and crushed. This micro-collapse part becomes an extreme condition of thousands of degrees and hundreds of atmospheres. There is a field called "sonochemistry" that promotes chemical reactions using this (Non-Patent Document 1).

This stimulus destroys heavy water molecules and irradiates the nuclei of radioactive atoms with deuterium bullets, causing nuclear excitation. Since the positive charge of one proton in the deuterium nucleus is weakened by one uncharged neutron, charge repulsion with the other nucleus is reduced, and it easily hits the other nucleus. Similarly, tritium atoms, which are formed by breaking tritiated water molecules, are even more likely to hit because the positive charge of one proton is weakened by two neutrons. That is why the planned international fusion project is tritium and deuterium collisions.

In water, most light water molecules form molecular network clusters by hydrogen bonding. The light water network is interspersed with heavy water molecules and tritiated water molecules. These dilute interspersed molecules are condensed into agglomerates by breaking up the web and encountering them by alternating transverse electric fields and downward ultrasonic vibrations.

In the light water molecule H ₂ O, the extranuclear electrons of the hydrogen atoms are shifted toward the oxygen atoms, so the hydrogen atoms H are slightly positively charged and the oxygen atoms O are slightly negatively charged. Water molecules are connected as hydrogen bonds by their attractive force, forming a molecular network. In addition, a small amount of water is always ionized into hydrogen ions H ⁺ and hydroxyl ions OH ^- . When a transverse DC electric field is applied, the H ^{2 +} migrates to counteract the negative charge of the oxygen atoms, so that the water molecules break their hydrogen bonds and become positively charged free-flowing particles. Furthermore, the movement of hydroxyl ions ^OH- cuts through the molecular network. Then, ultrasonic vibration is applied downward from above to cause heavy water molecules and tritium water molecules to descend and meet, forming molecular masses and concentrating them. The upper water is separated and drained.

The Story of Sonoprocess -Use of Ultrasound in Chemical Engineering-: Yasuo Iida, Nikkan Kogyo Shimbun, 2006.

The present invention solves the problem of contaminated water at the Fukushima Daiichi Nuclear Power Plant after the accident, and the problem of tritiated water generated by the constant operation of reprocessing plants and PWR nuclear power plants in Japan and around the world.

In order to solve the above problems, the present invention puts radioactively contaminated water in the descending concentration treatment tank in the upper part of FIG. The tritium water molecules and heavy water molecules are frozen by dropping into a cooling concentration tank and further concentrated. The freezing point of tritiated water and heavy water is around 2°C, which is higher than 0°C of light water. The concentrated frozen and separated tritiated water and heavy water are transferred to the <Nuclear Excitation Beta Decay Device>, which performs the final treatment of the radioactively contaminated water shown in Fig. 3. Radioactive atoms are converted into stable atoms using heavy water molecules and tritiated water molecules. converted.
(1) On both sides of the rectangular deconcentration treatment tank shown in the upper part of FIG. The traces of hydrogen ions H ⁺ and OH ⁻ ions that water naturally decomposes move laterally to break the hydrogen bonding network of water molecules and release light water molecules from the hydrogen bonding.
(2) Furthermore, ultrasonic vibration is applied from the upper surface of the rectangular concentrating tank to cause the isolated heavy water molecules and tritium water molecules to descend, encounter each other to form molecular masses, and collect them in the lower concentrating liquid tank.
(3) When radioactive elements other than tritium are contained, they are all metallic elements and are heavier than water molecules, so they are lowered downward in the same manner.
(4) Operate the three-way valve connecting the upper descending concentration tank and the lower concentrated liquid tank to discharge the water in the upper treatment tank.
(5) In the freeze concentration tank of FIG. 2, tritiated water and heavy water are frozen at the bottom at around 2°C, which is slightly higher than the light water freezing temperature of 0°C. Light water on ice releases.
(6) The frozen and thawed liquid in Fig. 2 is transferred to the <Nuclear excited β-decay device> in Fig. 3. Radioactive contaminated water is added and ultrasonic vibration is emitted from the side to promote β-decay. . There is a rotating plate on the bottom, and the center of the liquid surface can be depressed. It is used for nuclear excitation of light floating atoms such as ^14C .

After the accident, the radioactive contaminated water from the Fukushima Daiichi Nuclear Power Plant and the radioactive contaminated water from nuclear facilities in Japan and around the world will be detoxified and discharged.

Equipment for concentrating radioactively contaminated water containing tritiated water and uranium fission atoms. Bottom freeze concentrator. Nuclear-excited β-decay device.

1... Contaminated water supply pipe, 2... Rectangular concentrating cylinder, 3... Alternating direct current voltage, 4... Insulated coated electrode net plate, 5... Horn-type ultrasonic head, 6... Three-way cock, 7... Two-way cock, 8. 9...Water discharge, 10...Water transfer, 11...Concentrated water, 12...Bottom freezing concentration tank, 13...Freezing head, 14...Radiation shielding, 15...Ultrasonic umbrella-shaped head, 16...Rotating circle that makes the liquid surface like a mortar board.

・Upper square concentration treatment tank: 1m x 1m x 5m height = 5m ³
- Descent speed: 1 cm/5 sec. 5 m = 500 cm → 2500 seconds → 42 minutes ・Water supply → concentration drop → (water discharge) → concentrated water is separated into the lower concentrated liquid tank → freezing at the bottom of the concentrated liquid tank → (water discharge) → water transfer to nuclear excited β decay device The total process processing time is 90 minutes.
・60 minutes/hour x 24 hours = 1440 minutes, 1440 minutes/90 minutes = 16 times/day ・16 times/day x 6 days/week x 4 weeks/month x December/year = 4606 times/year, ^5m3 × 4606 times/year = 23030 m ³ /year・23030 m ³ /year/vehicle × 10 units/train × 2 trains = 460,600 m ³ /year, 460,600 m ³ /year × 2 years = 921,200 m ³ <460,600 m ³ /year × 3 years = 1,281,800 m ³ ; Treatment of water stored in tanks at Fukushima Daiichi Nuclear Power Plant can be completed in less than three years.

・A large number of horn-type vibrators are installed on the upper liquid surface of the drop concentration tank.
・Three-way valve in the middle narrow cylinder: Opens to the lower concentrated liquid tank during treatment, and opens on the side after treatment to release water.
・<Nuclear-excited β-decay device>: Using tritium atoms and deuterium atoms as blessing bombs, radioactive atoms in contaminated water are β-decayed and converted into stable atoms by the bubble crushing impact of the ultrasonic oscillator on the side.

Although the Fukushima Daiichi Nuclear Power Plant was an explosion accident caused by an undersea earthquake, PWR and heavy water reactors that constantly emit a large amount of tritium water, and wastewater from spent nuclear fuel reprocessing plants will be rendered harmless.

Claims (4)

Heavy water reactor, PWR reactor, post-explosion Fukushima Daiichi Nuclear Power Plant, Windscale in the UK, La Hague in France, Tokai-mura, and Rokkasho-mura spent nuclear fuel reprocessing plants. An insulating coating electrode is attached to the surface and a DC voltage that changes in minutes is applied to destroy light water molecule clusters, and ultrasonic vibration is applied from the top of the cylinder to force the scattered tritium water molecules and heavy water molecules to fall. A method of creating concentrated water of heavy water and tritiated water by making molecular lumps by chance. If the totium water described in the previous section contains radioactive atoms resulting from nuclear fission of uranium, the atomic weight is 20 or more and is heavier than water. A method of concentrating and separating by cooling the descending concentrated water in the preceding paragraph to around 1 to 2°C and freezing the tritium water and heavy water at the bottom. The positive charge of the hydrogen nuclei is weakened by neutrons, weakening the net positive charge. Even more than the easiest nuclear fusion, which collides tritium (1 proton, 2 neutrons) with deuterium (1 proton, 1 neutron). β decay, which stabilizes the nucleus by colliding tritium or deuterium with uranium fission nuclei, or colliding deuterium with tritium to reduce neutrons in a neutron-rich state, is called the enriched separated water in the preceding paragraph. A method forcibly generated by ultrasonic vibration bubble crushing impact using .

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