JPH01189337A - Isotope separator - Google Patents

Abstract

PURPOSE:To prevent thermoionization ions of impurities from being mixed into the product recovery electrodes and te improve the separation efficiency of a specified isotope by arranging the electrodes impressed with voltage across the directions of vapor streams to the lower parts of respective electrodes of the product recovery electrodes. CONSTITUTION:A crucible 4 held with metal 3 for evaporation is arranged in a vacuum vessel 2 and also the evaporation flows 7 of metal 3 is allowed to generate by a heat source 5. Further the product recovery electrodes 10 consists of positive electrodes and negative electrodes which are alternately arranged to the directions crossing to the vapor flows 7 and vertically provided to the upper part of the crucible 4 and impressed with voltage. Furthermore, a waste recovery plate 11 is provided so as to cover the upper parts of the electrodes 10 and laser beams 9 crossing to the directions of the vapor flows 7 are projected between both electrodes of these electrodes 10. In the thermoionization ion removing devices 12, the electrodes 14 impressed with voltage are arranged across the directions of vapor flows 7 to the lower parts of respective electrodes of the electrodes 10. As a result, the separation efficiency of a specified isotope being a recovery object can be enhanced.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to an apparatus for separating only a specific isotope from a substance containing multiple types of isotopes, and in particular to a device for separating only a specific isotope from a substance containing multiple types of isotopes. This invention relates to an isotope separation device that performs.

(Prior Art) Isotope separation devices using laser light are used, for example, in the process of concentrating isotopes that cause nuclear fission from natural raw materials in order to produce fuel for nuclear reactors.

A conventional example of an isotope separation apparatus using laser light will be described below with reference to FIGS. 6 and 7. FIG. 6 is a vertical cross-sectional view schematically showing a conventional example of an isotope separation apparatus using laser light, and FIG. 7 is a cross-sectional view taken along arrows 1--2 in FIG. The isotope separation device indicated by the reference numeral 1b in the figure is placed at the bottom of a vacuum container 2, and emits an evaporation crucible 4 containing a metal 3, which is an isotope mixture, and an electron beam 6 as a heat source for heating the metal 3. It is equipped with a linear electron gun 5. A collimator 8 that guides the flow direction of the vapor flow 7 evaporated from the metal 3 is provided above the side surface of the evaporation crucible 4, and furthermore, a collimator 8 is provided in the space above the collimator 8 in a direction that is not interlinked with the flow direction of the vapor flow 7. A product recovery electrode 10 is provided, which is made up of electrodes and negative electrodes arranged alternately in parallel, and an electric field is applied between these two electrodes.

Further, a waste product collection plate 11 is provided above the product collection electrode 10 so as to cover it. In addition, as shown in FIG. 7, a laser beam 9 adjusted to a wavelength that selectively excites and ionizes only a specific isotope is irradiated into the space between each electrode of the product recovery electrode 10 in the longitudinal direction of each electrode. It is configured to do this.

The metal 3 housed in the evaporation crucible 4 is irradiated with an electron beam 6 emitted from a linear electron gun 5 while being deflected by a deflecting magnetic field, and the metal 3 is heated and evaporated to generate a vapor flow 7. The vapor flow 7 rises inside the collimator 8 and is introduced into the space between each electrode of the product recovery electrode 10. put it here,
For the vapor flow 7, excite only a specific isotope in the vapor flow 7,
A laser beam 9 having a wavelength that causes ionization is irradiated, and only the specific isotope is excited to become an ion. The isotope ions are attracted to the negative electrode by the electric field applied between the electrodes, adhere to the surface of the negative electrode, and are recovered as a product. on the other hand,
Since the isotope that is not ionized is a neutral atom, it passes through the product collection electrode 10 without being affected by the electric field, and is collected by adhering to the secondarily disposed waste product collection plate 11.

(Problems to be Solved by the Invention) In general, in an isotope separation device having the above configuration, in order to improve separation efficiency, it is important to selectively and efficiently ionize only the specific isotope that is the object of recovery. It is.

In the isotope separation device 1b, the generated vapor flow 7 comes into contact with the electron beam 6 as it rises. Due to the electron impact caused by this contact, some of the neutral atoms in the vapor flow 7 may be ionized and become thermoionized ions. Ionization due to this contact is
Since this is carried out non-selectively using atoms, atoms other than the specific isotope that is the object of recovery are also ionized and introduced into the product recovery electrode 10 as impurity thermoionized ions. This impurity thermoionized ion is also affected by the electric field together with the specific isotope that is the object of recovery that has been ionized by the laser beam 9, and is attracted to the negative electrode and collected, resulting in a reduction in the separation efficiency of the specific isotope. There was a point.

The present invention was made to solve these problems, and by preventing impurity thermoionized ions from entering the product recovery electrode, it is possible to obtain an isotope with high separation efficiency of the specific isotope that is the object of recovery. The purpose is to provide a separation device.

[Structure of the invention]

(Means for Solving the Problems) An isotope separation apparatus according to the present invention includes a vacuum container, an evaporation crucible for accommodating a metal disposed in the vacuum container, and an evaporation crucible for generating a vapor flow of the metal. a heat source, a product recovery electrode consisting of a positive electrode and a negative electrode to which a voltage is applied, which are arranged in parallel and arranged alternately in a direction not interlinked with the flow direction of the vapor flow above the evaporation crucible; and the product recovery electrode. An isotope comprising a waste product collection plate arranged to cover above an electrode, and configured to irradiate a laser beam interlinked with the flow direction of the vapor flow between both electrodes of the product collection electrode. The separation device is characterized in that a thermoionized ion removal device is provided in which electrodes to which a voltage is applied are arranged below each electrode of the product recovery electrode so as to be interlinked with the flow direction of the vapor flow. shall be.

(Function) The metal, which is an isotopic mixture housed in the evaporation crucible, is melted by heating by an electron beam or the like generated from a heat source such as an electron gun, and evaporates into a vapor stream.

As this vapor flow rises within the vacuum container, a portion of it becomes thermally ionized ions due to contact with the electron beam, etc., and is introduced into the thermally ionized ion removal device.

Due to the voltage applied to the electrodes of the thermal ion removal device, the thermal ionization ions in the vapor stream are attracted to the electrodes of the device, deposit on the electrodes, and are removed from the vapor stream. Therefore, a vapor flow consisting only of neutral atoms that does not contain thermoionized ions as impurities other than the specific isotope that is the object of recovery is introduced into the product recovery electrode.

(Embodiment) Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a vertical sectional view schematically showing a first embodiment of the present invention, and FIG. 2 is an enlarged perspective view of the main part of the first embodiment. Note that the same parts as those in the conventional example already explained are denoted by the same reference numerals, and redundant explanation will be omitted.

The isotope separation device indicated by the reference numeral 1 in FIG.
An evaporation crucible 4 and a linear electron gun 5 that emits an electron beam 6 to heat the metal 3 housed in the evaporation crucible 4 are provided at the inner bottom of the evaporation crucible 4 . A collimator 8 is provided above the evaporation crucible 4 to guide the flow direction of the vapor flow 7 generated from the metal 3. Further, in the space above, a product recovery electrode IO is provided, which is made up of a plurality of positively charged horizontal plates and negative electrode plates arranged in parallel in an alternating manner along the flow direction of the vapor flow 7, and between the image electrode plates. An electric field is applied to. Further, a laser beam having a wavelength that excites and ionizes only a specific isotope in the vapor flow 7 is irradiated between the picture electrode plates in a direction perpendicular to the plane of the drawing. In addition, the product recovery electrode 10
A waste collection plate 11 is provided over the entire upper part of the container. Thermionic ion removal device 12 is provided below each electrode plate of product recovery electrode 10. This thermoionized ion removal device 1
2, as shown in FIG.
A plurality of electrode plates 14 are arranged side by side and fixed to the insulating bone with a screw, and a voltage is applied to the electrode plate 14 by a power supply device (not shown) connected via a cable 16.

The metal 3 housed in the evaporation crucible 4 is heated and evaporated by irradiation with the electron beam 6, and becomes a vapor flow 7. steam flow 7
As it rises, it comes into contact with the electron beam 6, and a part of it is ionized by electron impact and becomes thermoionized ions. These thermoionized ions contain ions of components other than ions of the specific isotope of the object to be recovered as impurities. The vapor stream 7 containing thermionic ions is introduced inside the collimator 8 into the thermionic ion removal device 12 . Here, the thermoionized ions in the vapor flow 7 are attracted to the electrode plate 14 by the voltage applied to the electrode plate 14, adhere thereto, and are separated and removed from the vapor flow 7. Therefore, a vapor flow 7 consisting only of neutral atoms containing no thermally ionized ions is introduced into the product recovery electrode 10 , and a specific isotope of the object to be recovered is ionized by irradiation with the laser beam 9 . It is attracted by the electric field, adheres to it, and is collected. The number of electrode plates 14 of the thermoionized ion removal device 12, the voltage value to be applied, and the combination thereof may be selected as appropriate for the steam flow valve to be applied. By applying a negative voltage to the electrode plate 14, electrons contained in the vapor flow 7 can also be removed. Furthermore, the structure of the electrode plate support 15 is not limited to that shown in FIG. 2.

Next, other embodiments of the present invention will be described with reference to FIGS. 3, 4, and 5.

FIG. 3(a) is a vertical sectional view schematically showing a second embodiment of the present invention, and FIG. 3(b) is an enlarged sectional view of section A in FIG. 3(a). The isotope separation device indicated by reference numeral 1a in the figure is characterized in that the width of the electrode plate 14a of the thermoionized ion removal device 12a is made wider as it approaches the product recovery electrode 10. When the electrode plate 14a is arranged in this manner, a collimation effect that can prevent the vapor flow 7 from adhering to the product recovery electrode 1o is obtained, and product separation efficiency is improved.

FIG. 4 is an enlarged perspective view of a main part of a third embodiment of the present invention. The third embodiment is characterized in that the thermoionized ion removal device 12c is configured with a counter electrode 17 in the same direction as the product recovery electrode 10.

FIG. 5 is an enlarged perspective view of a main part of a fourth embodiment of the present invention. The fourth embodiment is characterized in that the thermal ion removal device 12d is configured by a combination of a counter electrode 17 and an electrode plate 14. According to these third and fourth embodiments,
Furthermore, specific isotopes can be separated and recovered more efficiently.

〔Effect of the invention〕

According to the present invention, by removing thermoionized ions including impurity ions before product recovery, it is possible to improve the separation efficiency of the specific isotope that is the object of recovery.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view schematically showing a first embodiment of the present invention, FIG. 2 is an enlarged perspective view of the main part of the first embodiment, and FIG.
) is a vertical sectional view showing the second embodiment of the present invention, and FIG.
) is an enlarged cross-sectional view of part A in FIG. FIG. 7 is a longitudinal cross-sectional view schematically showing a conventional example, and FIG. 7 is a cross-sectional view taken along the line 1-1 in FIG. 6. 1, la, lb... isotope separation device, 2... vacuum container, 3... metal. 4... Evaporation crucible, 5... Linear electron gun,
6...electron beam, 7...vapor flow. 8... Collimator, 9... Rayza light, 10
... Product collection electrode, 11... Waste product collection board. 12, 12a, 12c, 12d - Thermal ion removal device, 14... Electrode plate, 15... Electrode plate support, 16... Cable, 17... Counter electrode. Applicant's agent Patent attorney Nori Ken Yudo Daishimaru
Ken Figure 1 Figure 2 Figure 3 (Kyu) Figure 3 (b) Figure 4 Figure 5 ≠ Ni-I Figure 6 Figure 7

Claims (1)

[Claims] a vacuum container, an evaporation crucible for accommodating metal disposed in the vacuum container, a heat source for generating an evaporation flow of the metal, and above the evaporation crucible interlinked with the flow direction of the vapor flow. a product collection electrode consisting of a positive electrode and a negative electrode to which a voltage is applied, which are arranged in parallel in a direction in which the product is collected; a waste product collection plate disposed to cover the top of the product collection electrode; In the isotope separation apparatus configured to irradiate a laser beam interlinked with the flow direction of the vapor flow between both electrodes of the product recovery electrode, an electrode to which a voltage is applied below each electrode of the product recovery electrode is connected to the electrode of the product recovery electrode. An isotope separation device characterized by being provided with a thermoionized ion removal device arranged so as to be interlinked with the flow direction of a vapor flow.