JP6773424B2 - Isotope separation device and isotope separation method - Google Patents

Description

The present invention relates to an isotope separation device and an isotope separation method.

¹ H ₂ ¹⁶ O hydrogen or oxygen isotopes include some that are radioactive. For example, tritium (tritium: T), which is an isotope of hydrogen existing in nature and has three neutrons, is known to be a radioactive substance having a half-life of about 12.3 years.

The hydrogen atom that makes up the water molecule is replaced with tritium, which is called tritiated water. The present embodiment, HTO, DTO, and _{T 2} O is, but exists primarily in the form of HTO. There are also water molecules in which the oxygen atoms that make up the water molecules are replaced by the isotopes ¹⁷ O and ¹⁸ O. Hereinafter, ¹ H ₂ ¹⁶ O is referred to as light water, and water having a mass larger than that of ¹ H ₂ ¹⁶ O and containing no tritium is referred to as heavy water. Further, water containing tritium like HTO or _{T 2} O is referred to as tritiated water. Furthermore, heavy water and tritiated water are collectively referred to as isotope water.

Separation, concentration, recovery and treatment of tritiated water from water containing tritiated water has been attempted and is an important technique in the nuclear industry. The conventional method for treating water containing tritiated water has been to dilute it to a concentration that does not affect the surrounding environment. However, in recent years, there has been a demand for separating and removing heavy water such as tritiated water from water used in nuclear power plants and the like.

Japanese Unexamined Patent Publication No. 2015-80748

An object of the present invention is to provide an isotope separation apparatus and an isotope separation method capable of efficiently separating isotope water from water containing isotope water and light water.

In the isotope separation method according to the embodiment of the present invention, in order to solve the above-mentioned problems, isotope water which is water containing at least one of oxygen and hydrogen isotopes in water molecules and oxygen and hydrogen in water molecules. A mist generation step of generating droplets from a liquid containing light water, which is isotope-free water, and pressure is applied to the liquid in a tube having an opening to airtightly separate the liquid from the opening. A mist separation step of separating the droplets based on the density by injecting into the container , and a mist recovery step of supplying purge gas to the separation container and collecting the low-density droplets among the separated droplets. The purge gas, which has been mist-recovered and separated from the droplets, is resupplied to the separation container.

In order to solve the above-mentioned problems, the isotope separating apparatus according to the embodiment of the present invention has an airtight separation container, heavy water which is water containing at least one of oxygen and hydrogen isotopes, and isotopes of oxygen and hydrogen. A liquid storage tank that holds a liquid containing light water, which is water that does not contain a body, and is connected to the separation container via a liquid supply flow path, and is supplied from the liquid storage tank via the liquid supply flow path. The liquid is sprayed into the separation container as droplets from the spray port to separate the droplets based on the density, and the purge gas to be held is supplied to the separation container to provide the density of the separated droplets. Separation of the purge gas supply source that transfers low droplets to the first flow path and the separation container that is connected to the separation container via the first flow path to separate and recover the droplets from the fluid of the purge gas containing the droplets. has a collecting means, a purge gas recovery means the purge gas that has been separated and recovered back into the purge gas supply source from the droplets, a second flow path for connecting the蓄液tank and the separating vessel, a pre The second opening, which is the opening of the second flow path that opens in the separation container, is the first opening that is the opening of the first flow path that opens in the separation container, and the said. The gas inside the separation container and the droplets floating inside the separation container are placed in the first flow path between the separation container and the separation / recovery means, which is provided at a position lower than the spray port. A second pump that transfers the liquid to the separation and recovery means and a second flow path between the separation container and the liquid storage tank transfers a fluid containing a liquid inside the separation container to the liquid storage tank. Has a pump and.

According to the embodiment of the present invention, isotope water can be efficiently separated from water containing isotope water and light water.

The schematic which shows the structure of the isotope separation apparatus which concerns on embodiment. The schematic diagram which shows schematic the structure which connected a plurality of isotope separation apparatus which concerns on embodiment. It is explanatory drawing explaining the example of the spraying means which the isotope separation apparatus which concerns on embodiment, and (A)-(C) is the schematic diagram which illustrates the spraying means which has the 1st to 3rd injection port part, respectively. , (D) is a schematic view illustrating the spraying means having the fourth to sixth injection ports. The schematic diagram which shows the structure of the modification of the isotope separation apparatus which concerns on embodiment. The table which shows an example of the test result of the isotope separation in the isotope separation apparatus which concerns on embodiment. The graph which showed an example of the test result of the isotope separation in the isotope separation apparatus which concerns on embodiment.

Hereinafter, the isotope separation apparatus and the isotope separation method according to the embodiment of the present invention will be described with reference to the drawings. A liquid mainly composed of light water and containing heavy water is referred to as water. Water may contain ionic components derived from atoms different from hydrogen and oxygen, such as sodium ion (Na ⁺ ) and chloride ion (Cl ⁻ ).

In this embodiment, heavy water is separated by making water into minute droplets. Hereinafter, minute droplets of water are referred to as water particles. Further, forming water particles from liquid water is called mist formation. Water particles have a different form than water vapor. Water vapor is formed by aggregating several water molecules, and water particles are formed by aggregating at least 100 or more water molecules, both of which are different in size. Further, water particles are formed by injecting water by applying ultrasonic waves or pressure, but water vapor is mainly formed by evaporating by heating with water.

Assuming that water containing isotope water and light water is water particles, the proportion of isotope water contained differs from particle to particle. Water molecules of isotope water have a larger mass than water molecules of light water, and water particles containing more isotope water have a higher density than particles containing less isotope water or particles containing no isotope water at all. Become. Therefore, by using water as water particles and collecting water particles having a high density, isotopic water components such as tritiated water can be concentrated and separated from water.

Hereinafter, the configuration of the isotope separation device 50 of the present embodiment will be described. FIG. 1 is a configuration diagram schematically showing the configuration of the isotope separation device 50.

The isotope separation device 50 includes a separation container 11 in which water particles are ejected inside, a spray means 12 for injecting water particles into the separation container 11, and a transfer means 13 for transferring water particles from the inside of the separation container 11 to the outside. , A separation and recovery means 17 that separates and recovers predetermined water particles from the fluid transferred from the transfer means 13, and a control unit 15 that controls the operation of each configuration in the isotope separation device 50. To. Each configuration will be described below.

The separation container 11 is, for example, a cylindrical airtight container. The separation container 11 is provided with a pressure detecting unit 27a for detecting the pressure in the gas phase region in the separation container 11 and a pressure adjusting means 27b capable of adjusting the pressure in the separation container 11. The pressure adjusting means 27b is, for example, a compressor or a pump, and sucks or supplies gas from the separation container 11 to adjust the pressure in the separation container 11.

The spraying means 12 is connected to a liquid storage tank 19 in which the liquid to be treated 1 which is water before being treated by the isotope separation device 50 is stored via a flow path 16. A pump 121 is provided in the flow path 16 between the liquid storage tank 19 and the spraying means 12, and the liquid 1 to be treated is supplied from the liquid storage tank 19 to the spraying means 12 by the pump 121.

The liquid storage tank 19 is provided with a temperature detecting unit 26a for detecting the liquid temperature of the liquid to be treated 1 and a temperature adjusting means 26b for adjusting the liquid temperature of the liquid to be treated 1. The temperature adjusting means 26b is, for example, a heater, and the water temperature of the liquid to be treated 1 can be adjusted by changing the operation of the heater.

The spraying means 12 sprays the liquid to be treated 1 into the separation container 11 to atomize at least a part of the liquid to be treated 1 introduced into the separation container 11 to generate water particles. Here, the water particles are droplets of a minute liquid to be treated 1 having an average particle size of less than 100 micrometers [μm].

For example, as shown in FIG. 3A, the spraying means 12 faces the opening 28a, which is the open end of the pipe 28 protruding into the separation container 11, and the opening 28a of the water to be treated 1 in the pipe 28. It is provided with a pressurizing means for pressurizing. In this embodiment, the pipe 28 is a pipe continuous from the flow path 16. In FIG. 1, the pump 121 is responsible for pressurizing the untreated water 1 in the pipe 28 toward the opening 28a. The pressurizing means for pressurizing the untreated water 1 in the pipe 28 toward the opening 28a may be provided with a pump different from the pump 121.

The untreated water 1 pressurized by the pump 121 in the pipe 28 is ejected from the opening 28a into the separation container 11 to become water particles. Water particles are ejected from the opening 28a containing a horizontal component. Also, less dense water particles fall slower than more dense water particles. Therefore, the higher density water particles fall to a position closer to the horizontal direction of the opening 28a, and the lower density water particles float to a position farther horizontally from the spout. Hereinafter, the opening 28a of the spraying means 12 for injecting the water 1 to be treated into the separation container 11 is referred to as an injection port 122.

Next, the separation / recovery means 17 has a configuration for separating and recovering predetermined water particles from the fluid transferred from the transfer means 13, for example, a classifier and gas-liquid connected to the separation container 11 via the flow path 18. It is a separator. A classifier collects water particles of a predetermined density, and a gas-liquid separator separates the water particles of a predetermined density from the gas. It is preferable that the opening of the flow path 18 in the separation container 11 is provided at the same height as the injection port portion 122. Further, the separation / recovery means may have at least one of a sedimentation separator, a centrifuge, a packing layer, a wire mesh filter, a scrubber, a cyclone, an electrostatic precipitator and an inertial separator.

A suction pump 13a is provided in the flow path 18 between the separation / recovery means 17 and the separation container 11. Further, the isotope floor separation device 50 includes a purge gas supply source 22 for supplying the purge gas 6 into the separation container 11 and a purge gas supply pump 13b for ejecting the purge gas into the separation container 11. The suction pump 13a, the purge gas supply pump 13b, and the purge gas supply source 22 are collectively referred to as a transfer means 13.

The purge gas supply source 22 is connected to the separation container 11 via the flow path 23, and the purge gas supply pump 13b is provided in the flow path 23 between the purge gas supply source 22 and the separation container 11. It is preferable that the opening of the flow path 23 in the separation container 11 is provided at a position lower than the opening of the flow path 18 in the separation container 11. The purge gas 6 in the flow path 18 is pressurized by the purge gas supply pump 13b and ejected from the opening in the separation container 11 of the flow path 23.

The purge gas 6 ejected from the opening in the separation container 11 of the flow path 23 is ejected toward a portion where the low-density water particles are suspended at a position higher than the high-density water particles.

The suction pump 13a is composed of, for example, a pump or a compressor, sucks water particles together with the gas in the separation container 11, and transfers the water particles to the separation / recovery means 17. The opening of the flow path 18 in the separation container 11 has a height similar to that of the injection port portion 122, and the low-density particles blown up by the flow path 18 are more selectively sucked by the suction pump 13a. The water particles sucked by the suction pump 13a and the gas in the separation container 11 are sent to the separation / recovery means 17, and the water particles are classified. Depending on the position of the opening of the flow path 18 in the separation container 11 and the position where the low-density particles are suspended, the low-density particles can be sucked without being blown up by the purge gas 6. In that case, the purge gas supply pump 13b and the purge gas supply source 22 may not be provided.

A flow path 34a is connected to the separation / recovery means 17, and the low-density water particles 2a are discharged from the flow path 34a to the outside of the isotope separation device 50. The high-density water particles 2b are transferred from the flow path 34b connected to the separation / recovery means 17. The flow path 34b is connected to the separation container 11, and the high-density water particles 2b transferred from the flow path 34b are returned to the separation container 11.
When the water particles flowing into the flow path 18 have already reached a desired density, the separation / recovery means 17 may simply be a gas-liquid separator that separates the liquid particles from the gas. In that case, the flow path 34b may not be provided.

As the purge gas 6, for example, air is used. In addition to air, for example, nitrogen (N ₂ ), oxygen (O ₂ ), or a rare gas such as helium (He), neon (Ne), argon (Ar), krypton (Kr), or xenon (Xe). A gas containing at least one of these may be used as the purge gas 6.

The isotope separation device 50 may include a purge gas recovery means 14. The purge gas recovery means 14 is connected to the separation and recovery means 17 via the flow path 7, and is connected to the purge gas supply source 22 via the flow path 5. It is assumed that the purge gas recovery means 14 is, for example, a pump that recovers the gas separated by the separation / recovery means 17 and supplies the gas to the purge gas supply source 22.

The separation container 11 is connected to the liquid storage tank 19 not only by the flow path 16 but also by the flow path 21. The opening of the flow path 21 in the separation container 11 is provided at a position lower than the opening of the flow path 16 and the flow path 18 in the separation container 11. A pump 24 is provided in the flow path 21, and sucks water particles in the separation container 11 and supplies the water particles to the liquid storage tank 19. The opening of the flow path 21 in the separation container 11 is provided at a position lower than the opening of the flow path 16 and the flow path 18 in the separation container 11, and higher density water particles are sucked. It is returned to the liquid storage tank 19.

Since it is possible that the water particles have returned to the liquid at the bottom of the separation container 11, the pump 24 may be configured so that the liquid can also be recovered. Further, a gas-liquid separator may be provided in the flow path 21.

The control unit 15 is communicably connected to the pressure detecting unit 27a, the pressure adjusting means 27b, the temperature detecting unit 26a, the temperature adjusting means 26b, the pump 121, the transfer means 13, the spraying means 12, and the pump 24. For example, it may be connected by wire or by wireless means. Further, it may be operated by a worker, or may be connected to a database or a computer and operated automatically.

Hereinafter, the function of the control unit 15 will be described. The control unit 15 adjusts the temperature of the water 1 to be treated in the liquid storage tank 19, the pressure in the separation container 11, the transfer amount of water particles, and the supply amount of water particles.

In order to control the temperature of the water to be treated 1 in the liquid storage tank 19, the control unit 15 receives the temperature information of the water to be treated 1 from the temperature detection unit 26a. Then, in light of the information in the database or the like, the operation of the temperature adjusting means 26b is adjusted so that the liquid temperature of the liquid to be treated 1 is within a desired adjustable range. For example, the on / off (ON / OFF) state of the temperature adjusting means 26b is switched.

By adjusting the temperature of the water to be treated 1, the viscosity of the liquid to be treated 1 can be adjusted, and the amount of water particles generated can be changed. By adjusting the temperature of the water to be treated 1 to an appropriate temperature, the amount of water particles generated can be increased. Further, by periodically changing the temperature, the distribution of the water particles 2 in the separation container 11 can be adjusted. Further, during maintenance of the apparatus, by adjusting the temperature of the liquid to be treated 1, it is possible to dissolve and easily remove the scale adhering to the inside of the flow path 16.

The temperature adjusting means 26b and the temperature detecting unit 26a may be integrally configured or may be individually configured independently (as individual devices).

Further, in order to adjust the pressure in the release vessel 11, the control unit 15 receives the pressure information of the gas phase region in the release vessel 11 detected by the pressure detection unit 27a. Then, in light of the information in the database or the like, a pressure adjustment command is given to the pressure adjusting means 27b so that the pressure in the gas phase region in the release container 11 is within a desired range.

The pressure adjusting means 27b, which has received the pressure adjusting command given from the control means 15, adjusts the pressure in the gas phase region in the separation container 11 based on the received pressure adjusting command. Separation based on the finding of the inventor that the pressure of the gas phase portion in the separation container 11 is 0.1 kilopascals [kPa] or more and 150 kilopascals [kPa] or less is suitable for mistizing the liquid to be treated 1. The pressure of the gas phase portion inside the container 11 is controlled to be about 0.1 kPa to 150 kPa.

Further, in order to adjust the transfer amount of water particles, the control means 15 sends a command to the gas suction means 13a, the purge gas supply means 13b, and the pump 24 to adjust the operation of each. For example, the on / off (ON / OFF) state of the gas suction means 13a, the purge gas supply pump 13b, and the pump 24 is switched.

Further, the supply amount of water particles can be adjusted by adjusting the temperature of the water 1 to be treated and by changing the operation of the pump 121. The control means 15 sends a command to the pump 121 to adjust its operation. For example, the on / off (ON / OFF) state of the pump 121 is switched.

Next, the isotope separation method of the present embodiment will be described.

The isotope separation method using the isotope separation apparatus 50 includes a mist generation step of generating water particles from the liquid to be treated 1 and a mist recovery step of recovering low-density water particles among the generated water particles. ..

The mist generation step will be described below. The water to be treated 1 is supplied from the liquid storage tank 19 to the spraying means 12 by the pump 121, and water particles are sprayed from the spraying means 12 into the separation container 11. Of the water particles ejected into the separation container 11, the high-density water particles 3 fall downward in the separation container 11, and the low-density water particles 2 are located higher than the high-density water particles in the separation container 11. Float in.

The mist recovery step will be described below. The low-density water particles 2 in the separation container 11 are pushed up by the purge gas 6 ejected upward, and are sucked together with the gas from the opening of the flow path 18 by the pump 13a to reach the separation / recovery means 17. The separation / recovery means 17 separates the water particles from the gas. The separated water particles are transferred from the flow path 34 to the outside of the isotope separation device 50. Further, the high-density water particles 3 in the separation container 11 are sucked by the pump 24 from the opening of the flow path 21 in the separation container 11 and returned to the liquid storage tank 19.

By repeating the above steps, the isotope water component can be concentrated and recovered in the liquid storage tank 19, and the isotope water component can be separated from the light water.

In the isotope separation device 50 illustrated in FIG. 1, the recovered high-density water particles, that is, water containing a large amount of isotope water components is repeatedly treated in the device to concentrate the isotope water components. There is. As a modification, the flow path 34 can be connected to the liquid storage tank 19 to transfer the suctioned material from the flow path 21 to the outside of the device. Then, the recovered low-density water particles, that is, water having a smaller isotope water component can be repeatedly treated in the apparatus, and water having an extremely low isotope water component can be obtained.

Further, the isotope separation device 50 can separate and recover the isotope water component from the light water with higher accuracy by connecting a plurality of the isotope separation devices in series. FIG. 2 is a schematic view schematically showing a configuration in which a plurality of isotope separation devices according to the embodiment are connected. The first-stage isotope separation device is 50_1, the second-stage isotope separation device is 50_2, and so on. The nth stage isotope separation device shall be described as 50_n.

In the case of the nth stage isotope separation device, the flow path 34_ (n-1) of the (n-1) stage is connected to the liquid storage tank 19_n, and the (n-1) stage isotope separation device. The water 2_ (n-1) composed of the low-density water particles recovered in the above is processed by the nth stage isotope separation device. Further, the flow path 34_n of the n-th stage isotope separation device is connected to the liquid storage tank 19_ (n + 1) of the (n + 1) -th stage isotope separation device, and is recovered by the n-th stage isotope separation device. Water 2_n composed of dense water particles will be treated by the (n + 1) stage isotope separation device.

The water composed of water particles recovered from the flow path 34 may contain a trace amount of isotope water component, although it is less than that of the water to be treated 1. By connecting a plurality of isotope separation devices 50 in series, it is possible to further separate isotope water components from the water recovered from the flow path 23, and isotopes with higher accuracy than in the case of one stage. It is possible to separate and recover body water components.

Further, when the isotope separation apparatus 50 has a configuration of a modified example and the recovered low-density water particles are repeatedly treated in the apparatus, the liquid storage tank 19_n is in the (n-1) stage. The flow path 21_ (n-1) of the above is connected, and the water 3_ (n-1) composed of high-density water particles recovered by the isotope separation device of the (n-1) stage is the isotope separation of the nth stage. It will be processed by the device.

When the isotope separation device 50 is configured to repeatedly concentrate the isotope water component in the device, the pressure inside the device of the multi-stage isotope separation device 50 gradually decreases from the front stage to the rear stage. It is desirable to be controlled as such. On the other hand, when the isotope separation apparatus 50 is a modification thereof and has a configuration in which water having a smaller isotope water component is repeatedly treated in the apparatus, the internal pressure increases sequentially from the first stage to the second stage. It is desirable to be controlled so as to go.

Subsequently, a configuration example of the spraying means 12A to 12F, which is an example of the spraying means 12, will be described.

FIG. 3 is an explanatory diagram illustrating a configuration example of the spraying means 12A to 12F. More specifically, FIGS. 3A to 3C are schematic views illustrating spraying means 12A to 12C having first to third injection port portions 122A to 122C, respectively. D) is a schematic view illustrating spraying means 12D to 12F having fourth to sixth injection port portions 122D to 122F.

The spraying means 12A (FIG. 3A) is composed of, for example, a pipe 28 that is continuous from the flow path 16 and opens into the separation container 11. The injection port portion 122A of the spraying means 12A is an injection port portion 122 that opens into the separation container 11 of the pipe 28. In the spraying means 12A, the liquid to be treated 1 transferred from the liquid storage tank 19 side (upstream side) is sprayed from the injection port portion 122A into the inside of the separation container 11.

The spraying means 12B (FIG. 3B) is composed of, for example, a pipe 29 that is continuous from the flow path 16 and does not open into the separation container 11. At least one opening 29a is provided on the end surface 29b at the end of the pipe 29 on the separation container 11 side, and the opening 29a opens into the separation container 11. The diameter of the opening 29a is smaller than the inner diameter of the pipe 29. The injection port 122B of the spray means 12B is an opening 29a that opens into the separation container 11 of the pipe 29. In the spraying means 12B, the liquid to be treated 1 transferred from the liquid storage tank 19 side (upstream side) is sprayed into the separation container 11 from at least one opening 29a provided on the terminal surface 29b.

The spraying means 12C (FIG. 3C) is composed of, for example, a pipe 29 that is continuous from the flow path 16 and does not open into the separation container 11. The end of the tube 29 on the separation container 11 side protrudes into the separation container 11. Of the pipe 29, the side surface portion protruding into the release container 11 is referred to as a terminal region 29c. The injection port portion 122C of the spraying means 12C is an opening portion 29a, 29d provided at least one in the terminal region 29c and the terminal portion 29b, respectively. The opening 29a is an opening provided in the terminal 29b, and the opening 29d is an opening provided in the terminal region 29c. In the spraying means 12C, the liquid to be treated 1 transferred from the liquid storage tank 19 side (upstream side) is sprayed into the inside of the separation container 11 from the openings 29a and 29d.

The spraying means 12D to 12F (FIG. 3 (D)) are configured by attaching a device for spraying the liquid to be treated 1 as minute droplets to the terminal portion of the pipe 28 on the separation container 11 side (downstream side).

In the spraying means 12D, for example, a pressure sprayer 31b such as a one-fluid nozzle or a two-fluid nozzle that injects a liquid as minute droplets from the opening 31a using a pressure difference is at the end of the tube 28 on the separation container 11 side. It is attached to and configured. The injection port portion 122D of the spraying means 12D is an opening 31a of the pressure sprayer 31b provided at the end of the pipe 28.

The spraying means 12E is configured by, for example, an electrostatic sprayer (electrospray) 32b that charges a liquid from the opening 32a and ejects it as minute charged droplets, and is attached to the end of the tube 28 on the separation container 11 side. To. The injection port portion 122E of the spraying means 12E is an opening 32a of the electrospray 32b provided at the end of the pipe 28.

In the spraying means 12F (FIG. 3D), for example, a centrifugal sprayer (centrifugal atomizer) 33b that ejects a liquid as minute droplets from an opening 33a by using centrifugal force is provided on the separation container 11 side of the tube 28. It is constructed by being attached to the end. The injection port portion 122F of the spraying means 12F is an opening 33a of the centrifugal atomizer 33b provided at the end of the pipe 28.

In the spraying means 12, the Reynolds number (Re) of the liquid to be treated 1 when passing through the openings 28a, 29a, 29d, 31a, 32a, 33a of the injection ports 122A to F is 2400 or more (Re ≧). 2400) is preferable. The Reynolds number (Re) is a dimensionless number related to a fluid and is represented by the following equation (1).

Here, Re ≧ 2400 means that the liquid to be treated 1 which is a fluid is flowing as a turbulent flow, that is, the turbulent flow condition is satisfied. Therefore, in the illustrated spraying means 12, it means that the liquid to be treated 1 is flowing as a turbulent flow at the openings 28a, 29a, 29d, 31a, 32a, 33a (satisfying the turbulent flow condition). In other words, Re = 2400 is the Reynolds number (critical Reynolds number) when the fluid transitions from laminar flow to turbulent flow.

When Re <2400, that is, when the liquid to be treated 1 in the flow path 16 is flowing as a laminar flow, the velocity distribution of the liquid to be treated 1 in the flow path 16 is close to a uniform distribution. On the other hand, when Re ≧ 2400, that is, when the liquid to be treated 1 in the flow path 16 is flowing as a turbulent flow, a complicated flow is generally formed, and a vortex flow or the like is also generated.

Further, the pressure in the flow path 16 in the case of turbulent flow (Re ≧ 2400) is higher than that in the case of laminar flow (Re <2400), so that the liquid to be treated 1 is flowing as a laminar flow. The amount of mist (mist component 2) generated when the liquid to be treated 1 is sprayed can be increased when the flow is turbulent. Therefore, the isotope separation efficiency can be further improved by introducing the liquid to be treated 1 into the separation vessel 11 in a turbulent state.

Further, when a plurality of openings 29a are provided as in the spraying means 12B (FIG. 3B), it is preferable that Re is 2400 or more in at least one or more openings 29a. It is more preferable that Re is 2400 or more in more openings 29a. More preferably, Re is 2400 or more at all openings 29a.

In the isotope separation device 50 described above, the spraying means 12 is parallelized by a plurality of spraying means 12 selected from, for example, spraying means 12A to 12F, and the liquid to be treated 1 is used as necessary. The configuration may be such that one or more used for supplying the above can be selected.

Further, when the parallel spraying means 12 is adopted, it is preferable that the Reynolds number (Re) of the liquid to be treated 1 in each spraying means 12 is different. For example, even if the same spraying means 12B is adopted, each of them has the maximum flow velocity of the liquid to be treated 1 that can be transferred by the fluid pump 121 and the representative length that constitutes the flow path 16 (inner diameter for a circular pipe, hydraulic diameter for a rectangular pipe). ), It is preferable that the product has a different value. In this case, it is possible to widen the range of selection for selecting the flow path in which Re is 2400 or more in at least one or more openings 29a.

In the isotope separation device 50 described above, the spraying means (12A to 12F) need only be able to mist (make water particles) at least a part of the liquid to be treated 1, and the means for mistizing is arbitrary. That is, mist formation may be realized by means other than the spraying means 12A to 12F.

FIG. 4 is a modified example of the isotope separation device 50. FIG. 4 is a schematic view schematically showing the configuration of the isotope separation device 60 that employs the ultrasonic wave applying means 41 as the spraying means. In the isotope separation device 60 exemplified in FIG. 4, the ultrasonic wave applying means 41 is adopted as the spraying means 12.

Hereinafter, the configuration of the isotope separation device 60 will be described. The isotope separation device 60 is derived from the separation container 11, the ultrasonic application means 41 for generating water particles in the separation container 11, the transfer means 13 for transferring water particles from the inside to the outside of the separation container 11, and the transfer means 13. It is configured to include a separation and recovery means 17 for gas-liquid separation of the transferred fluid, and a control unit 15 for controlling the operation of each configuration in the isotope separation device 50. The control unit 15 is the same as the isotope separation device 50 and is not shown. Each configuration will be described below.

The separation container 11 is, for example, a cylindrical airtight container, and the water to be treated 1 is supplied from the outside of the apparatus, and the water to be treated 1 is stored in the lower part of the separation container 11. The region in which the liquid to be treated 1 exists in the lower part of the separation container 11 is referred to as a liquid phase region 8, and the portion above the liquid phase region 8 and filled with gas is referred to as a gas phase region 9.

For example, the ultrasonic wave applying means 41 is provided on the bottom surface of the separation container 11. The ultrasonic wave applying means 41 has a function of adjusting the frequency and output to output a desired ultrasonic wave. The ultrasonic wave applying means 41 applies ultrasonic waves to the liquid to be treated 1 stored in the bottom of the separation container 11. The ultrasonic wave applying means 41 applies ultrasonic waves traveling to the gas-liquid interface to the liquid 1 to be treated existing inside the separation container 11, and mist at least a part of the liquid 1 to be treated at the gas-liquid interface. To make it. Of the generated water particles, the low-density ones are distributed at a higher position, and the high-density ones return to the liquid phase or are distributed at a lower position in the gas phase region 9.

The position where the ultrasonic wave applying means 41 is installed is not limited to the bottom surface of the separation container 11 as long as the ultrasonic waves can be applied to the water 1 to be treated in the separation container 11. Further, in the isotope separation apparatus 60, at least a part of the liquid to be treated 1 can be mist-ized inside the separation container 11 regardless of the above-mentioned turbulent flow conditions.

The separation container 11 is provided with a pressure detecting unit 27a for detecting the pressure in the gas phase region 9 in the separation container 11 and a pressure adjusting means 27b capable of adjusting the pressure in the separation container 11. Further, a temperature detecting unit 26a for detecting the liquid temperature of the liquid to be treated 1 and a temperature adjusting means 26b for adjusting the liquid temperature of the liquid to be treated 1 are provided.

Further, the separation / recovery means 17 is connected to the separation container 11 via the flow path 18, and the purge gas supply source 22 is connected to the separation container 11 via the flow path 23. Then, the openings 61 and 62 both open in the gas phase region 9. Preferably, both the openings 61 and 62 are provided at a height at which low-density water particles are distributed.

A suction pump 13b is provided in the flow path 18 between the separation / recovery means 17 and the separation container 11. The gas and floating water particles in the separation container 11 are sucked from the opening 61 by the suction pump 13b, transferred to the separation / recovery means 17, and classified. The low-density water particles 2a are transferred to the outside of the isotope separation device 60 from the flow path 34a connected to the separation / recovery means 17. The high-density water particles 2b are transferred from the flow path 34b connected to the separation / recovery means 17. The flow path 34b is connected to the inside of the separation container, and the high-density water particles 2b transferred from the flow path 34b are returned to the inside of the separation container 11. Further, the gas recovered by the separation and recovery means 17 is recovered from the flow path 7 by the purge gas recovery means 14 and supplied to the purge gas supply source 22.

A purge gas supply pump 13b is provided in the flow path 23 between the purge gas supply source 22 and the separation container 11. The purge gas in the flow path 23 supplied from the purge gas supply source 22 is pressurized by the purge gas supply pump 13b, and is ejected into the separation container 11 from the opening 62 of the flow path 23. Similar to the isotope separation device 50, the suction pump 13a, the purge gas supply pump 13b, and the purge gas supply source 22 are collectively referred to as a transfer means 13. As the purge gas 6, a gas similar to that used in the isotope separation device 50 can be used.

Next, the isotope separation method in the isotope separation device 60 will be described. The isotope separation method using the isotope separation device 60 includes a mist generation step and a mist recovery step, as in the case of the isotope separation device 50.

The mist generation step will be described. In the mist generation step, the water 1 to be treated in the separation container 11 is mist-ized by the ultrasonic wave applying means 41, and water particles are generated. The water particles move from the liquid phase region 8 to the gas phase region 9.

The mist recovery step will be described. Purge gas 6 is ejected from the opening 62, gas is sucked in the opening 61, and a flow of the purge gas 6 from the opening 62 to the opening 61 is generated in the gas phase region 9. The water particles suspended in the gas phase region 9 are sucked from the opening 61 together with the purge gas 6 and transferred to the separation / recovery means 17.

The water particles are separated into low-density water particles 2a and high-density water particles 2b by the separation / recovery means 17. The high-density water particles 2b are returned to the separation container 11, and the mist generation step and the mist recovery step are repeated again. The low-density water particles 2a are transferred to the outside of the isotope separation device 60.

By repeating the above steps, the isotope water component can be concentrated and recovered in the liquid storage tank 19, and the isotope water component can be separated from the light water.

The isotope separation device 60 shown in FIG. 4 repeatedly treats the recovered high-density water particles, that is, water containing a large amount of isotope water components, in the device to concentrate the isotope water components. There is. However, by connecting the flow path 63b to the separation container 11 and transferring the contents from the flow path 63a to the outside of the apparatus, the recovered low-density water particles, that is, water having less isotopic water component Can be repeatedly processed in the apparatus. Then, it is possible to obtain water having an extremely small amount of isotope water components.

Further, similarly to the isotope separation device 50, the isotope separation device 60 can further separate and recover the isotope water component from the light water by connecting a plurality of the isotope separation devices in series.

According to the isotope separation devices 50 and 60 and their modifications, it is possible to efficiently separate isotope water from water containing isotope water and light water. Further, in the present embodiment, the isotope water component is separated and concentrated by generating water particles instead of steam from the water to be treated. The amount of energy required to make water particles without giving a large amount of heat to water is smaller than to heat water to make steam, so this embodiment is more efficient than the one using steam. It is possible to separate and concentrate body water components.

Subsequently, a separation test between heavy water and light water using the above-mentioned isotope separation device will be described.

Heavy water exists in environmental water such as seawater, river water, pure water, and tap water. For example, among heavy water, D ₂ O measured in this test is present at about 150 ppm in the vicinity of Kawasaki Ward, Kawasaki City, where the test was conducted, although there are some regional differences. In this separation test, diluted seawater obtained by diluting artificial seawater 5 times with pure water was used as the test water. The heavy water concentration of the test water used was 150 ppm.

In this separation test, the separation device used for separating heavy water and light water from the test water is an isotope separation device 60 that irradiates ultrasonic waves to generate water particles, as illustrated in FIG. Then, as shown in FIG. 3, two isotope separation devices 60 were connected and tested with n = 2.

First, test water is prepared as the liquid to be treated 1 inside the separation container 11 of the isotope separation device 60, and the frequency of the test water is 2.4 MHz [MHz] and the power consumption is over 20 watts [W]. The mist component 2 was generated inside the separation container 11 by irradiating with ultrasonic waves. Subsequently, among the generated water particles, the water particles floating in the separation container 11 were classified and recovered. The average particle size of the water particles sent to the separation / recovery means 17 was about 50 μm or less. Here, the cyclone method was used as a method for classifying and recovering water particles performed by the separation / recovery means 17.

Then, at regular intervals, the heavy water concentration of water composed of water particles classified and recovered and the heavy water concentration of the mother liquor composed of high-density water particles settling toward the bottom of the separation container 11 were measured. Water composed of water particles classified and collected is referred to as a treated liquid.

In addition, in evaluating the separation performance of heavy water and light water in this separation test, the ratio of the concentration of heavy water in the mother liquor to the concentration of heavy water in the treated liquid represented by the following formula (2) is defined as "separation degree". The degree of separation was used.

FIG. 5 is a table showing an example of the test results of isotope separation in the isotope separation device 60, and FIG. 6 is an explanatory diagram showing a graph of the table shown in FIG. The test is performed a plurality of times, and the test result of test 1 is indicated by a black circle, and the test result of test 2 is indicated by a white triangle mark.

As shown in FIGS. 5 and 6, in the isotope separation device 60, regardless of whether the separation method of the cyclone method or the gravity separation method is used, about 5% is normally obtained over 180 minutes (= 3 hours). I was able to confirm the degree of separation. As described above, in the isotope separation device 60 in which two units are connected in series, the reproducibility is good in a plurality of tests, and a degree of separation of about 5% can be normally achieved over 180 minutes.

As a result of the separation test described above is an example of separating the heavy water and light water that presents with D 2 _O, not limited to the case of the isotope separation. For example, it may isotopically water component, HDO, HTO, even when separating other hydrogen isotopes such as _{T 2} O. Further, the oxygen isotope may be separated. Furthermore, isotopes other than hydrogen and oxygen may be separated. In the example except when separating and between H _{2 O} and D _{2 O} as described above, the same effect as in the case of separating the illustrated between H _{2 O} and D _{2 O} has been confirmed. Further, even when the isotope separation device 50 is used, it is considered that a certain degree of separation is similarly achieved.

The present invention is not limited to the above-described embodiment as it is, and at the implementation stage, it can be implemented in various forms other than the above-described embodiment. The present invention can be omitted, added, replaced, or modified in various ways without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof.

1 Liquid to be treated 2a Low-density water particles 2b High-density water particles 3 High-density water particles 5 Flow path 6 Purge gas 7 Flow path 8 Liquid phase area 9 Gas phase area 11 Separation container 12 (12A to 12F) Spraying means 121 Pump 122 (122A to 122F) Injection port 13 Gas / liquid transfer means 13a Gas suction means 13b Purge gas supply means 14 Purge gas recovery means 15 Control unit 16 Flow path 17 Separation / recovery means 18 Flow path 19 Liquid storage tank 21 Flow path 22 Purge gas supply Source 23 Flow path 24 Pump 26a Temperature detection unit 26b Temperature adjustment means 27a Pressure detection unit 27b Pressure adjustment means 28 Tube 28a Opening 29 Tube 29a Opening 29b Termination surface 29c Termination area 31a Pressure sprayer opening 31b Pressure sprayer 32a Electrostatic Sprayer opening 32b Electrostatic sprayer 33a Centrifugal sprayer opening 33b Centrifugal sprayer 41 Ultrasonic application means 50,60 Isotope separator 61, 62 Opening

Claims (6)

Produces droplets from a liquid containing isotope water, which is water in which water molecules contain at least one of the isotopes of oxygen and hydrogen, and light water, which is water in which water molecules do not contain isotopes of oxygen and hydrogen. Mist generation step and
A mist separation step of applying pressure to the liquid in a tube having an opening and injecting the liquid from the opening into an airtight separation container to separate the droplets based on density.
A mist recovery step in which purge gas is supplied to the separation container and the low-density droplets among the separated droplets are collected.
An isotope separation method comprising a resupply step of resupplying the purge gas that has been mist-recovered and separated from the droplets to the separation container. With an airtight separation container
It holds a liquid containing heavy water, which is water containing at least one of the isotopes of oxygen and hydrogen, and light water, which is water containing no isotope of oxygen and hydrogen, and is placed in the separation container via a liquid supply flow path. With the connected liquid storage tank,
A spraying means for spraying the liquid supplied from the liquid storage tank through the liquid supply flow path into the separation container as droplets from the spray port and separating the droplets based on the density.
A purge gas supply source that supplies the purge gas to be held to the separation container and transfers the low-density droplets among the separated droplets to the first flow path.
A separation / recovery means that is connected to the separation container via the first flow path and separates and recovers the droplets from the fluid of the purge gas containing the droplets.
A purge gas recovery means for recovering the purge gas separated from the droplets and returning the purge gas to the purge gas supply source.
A second flow path connecting the separation container and the liquid storage tank,
Have ,
Second opening which is an opening of the second flow path that opens before Symbol separation vessel, the first opening is an opening of the first flow path opening into the separation vessel and It is provided at a position lower than the spray port and is provided.
A first pump that transfers the gas inside the separation container and the droplets floating inside the separation container to the separation and recovery means in the first flow path between the separation container and the separation and recovery means. When,
In the second flow path between the separation container and the liquid storage tank, a second pump for transferring the fluid containing the liquid inside the separation container to the liquid storage tank, and
Isotope separation device with. The spraying means
A pipe having an injection port that is continuous from the liquid supply flow path and opens inside the separation container.
The isotope separation device according to claim 2 , further comprising a pressure applying portion for applying pressure to the liquid in the pipe. The Reynolds number when the liquid flowing in the pipe passes through the spray portion is 2400 or more.
The isotope separation device according to claim 3 . A third flow path that connects the purge gas supply source and the separation container, opens in the separation container, and has a third opening provided at least below the first opening.
The isotope separation apparatus according to claim 2 , further comprising a third pump provided in the third flow path and transferring the purge gas from the purge gas supply source to the separation container. The isotope separation device according to claim 2 , wherein the separation / recovery means includes at least one of a sedimentation separator, a centrifuge, a packing layer, a wire mesh filter, a scrubber, a cyclone, an electrostatic precipitator, and an inertial separator. ..

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