JPS61164629A - Laser isotope separation apparatus - Google Patents

Abstract

PURPOSE:To efficiently perform the separation of dissociated <235>UF6 and non- dissociated UF6 or the separation of both components and carrier gas, by providing a recovery device having a structure for precipitating UF5, F2 and F6 or a structure for condensing and collecting UF5, F2, F6. CONSTITUTION:After UF6 from a UF6 tank 1 was mixed with carrier gas from a carrier gas tank 2, the resulting mixture is guided to a diabatic expansion nozzle 4 by a supply pipe 3 and discharged. Subsequently, laser is irradiated from selective exciting laser 6 and dissociation laser 7. Then, the dissociated UF6 molecule after the irradiation of laser is collectively recovered in recovery vessels 10a, 10b along with non-dissociated UF6 to at first separate non- condensible carrier gas. Succeedingly, UF6 and F2 being one component of dissociated UF5 are separated by sublimation. At least, remaining UF5 is reacted with F2 to form UF6 which is, in turn, taken out from the recovery vessels 10a, 10b. The above mentioned recovery vessels 10a, 10b comprise from a combination of two or more and alternately used.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a laser isotope separation device, and in particular, to a laser isotope separation device using uranium hexafluoride gas (hereinafter abbreviated as UF) as a separation work material. It is related to the device.

[Background of the invention]

In a laser isotope separation device that uses UF as the separation material, UF is generally added with an inert gas such as helium, argon, etc. as chiaria gas and injected from an adiabatic expansion nozzle, and this is the component of interest. By irradiating a laser precisely tuned to the absorption wavelength of 'UF,
is selectively excited and then dissociated into uranium pentafluoride (UF) and fluorine (F2) by the following reaction.

Since UF is a solid, undissociated UF and non-targeted UF can be separated using various mechanical methods. As shown in Patent No. 4,119,509,
A device is known in which a diffuser is provided downstream of a laser irradiation unit to separate molecules based on their light weight.

In addition, there is also a US document (Separating Iso
topes With La1ars, Los Alas
+sos 5science.

VoJl, 3 & 1 2-33 (1982))
It is published in the magazine. However, these devices have a problem in that the separation efficiency of UF is not necessarily good. In principle, only extremely low separation efficiency can be expected with separation using a diffuser, and UF with a jet impingement device.

Not only is it difficult to completely separate the UF, but there is also a risk that the precipitated UF may be scattered along with the jet and mixed into the UF and gas again.

[Purpose of the invention]

The purpose of the present invention is to provide dissociated UF, undissociated UF,
It is an object of the present invention to provide a laser isotope separation device that can efficiently separate chiaria gas from chiaria gas.

[Summary of the invention]

First, the basic principle of the device of the present invention created to achieve the above object will be described below.

In the present invention, the non-condensable chiaria gas is first separated by collecting the dissociated UF after laser irradiation and the undissociated molecules together in a recovery vessel.

Subsequently, UF and fluorine F2, which is one component of the dissociated UF, are separated by sublimation. Finally, the remaining UF,
is reacted with F8 to form UF, which is taken out from the recovery vessel.

In order to achieve the above object based on the above principle, the laser isotope fractionation apparatus according to the present invention irradiates a mixed gas of uranium hexafluoride with an inert gas as chiaria gas, and In a RAID isotope separation device that separates components of interest in uranium fluoride by selectively exciting and dissociating them, ・Uranium pentafluoride and fluorine, which are the substances produced in the above dissociation, and undissociated substances, A recovery vessel is provided to introduce a mixed gas of uranium hexafluoride and chiaria gas, and the recovery vessel is uranium pentafluoride.

Either a structure that deposits fluorine and uranium hexafluoride, or a structure that condenses and collects uranium pentafluoride, fluorine, and uranium hexafluoride, and

It is characterized by being configured so that Chiaria gas is discharged outside the recovery vessel.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG. 1st
In the figure, one separated working substance UF is supplied from a UF tank 1, mixed with Chiaria gas from a Chiaria gas tank 2, and then guided by a supply pipe 3 to an adiabatic expansion nozzle 4 and discharged.

Chiaria gas is added to enhance the cooling effect of UF, and helium has a high specific heat ratio.

An inert gas such as argon is used. The mixed flow of UF and Chiaria gas discharged from the nozzle is cooled by adiabatic expansion to a low temperature of 50 to 100 °C. The supercooled UP gas has a small molecular motion and an energy level close to the ground level. As a result, the optical absorption spectrum becomes sharp, and the absorption bands of the component of interest, "'UF," and the component of non-interest, "UF, (7)" are separated, and the absorption bands "'UF, (7)
7) Selective excitation by L/-zer becomes possible.

The UF in the above state is first irradiated with laser light through the irradiation window 5 using a selective excitation laser 6 whose wavelength is precisely tuned to the absorption rod of the UF.The wavelength of the laser is approximately 16 μm. The UFs that have been selectively excited to the excitation level by irradiation with a suitable zero beam are further irradiated with a dissociation laser 7 having a wavelength in the ultraviolet range,
, is 0″UF.

and F2.

``UFs after dissociation, F,, undissociated'' U Fa
The UF including and "UF" and the Chiaria gas are led to the collector via the exhaust pipe 8 and the pump 9. The above-mentioned collectors consist of a combination of at least two or more collectors, and are used alternately.

In this embodiment, two recovery vessels 10a and 10b are provided, and piping with a valve device is provided so that they can be used alternately.

The mixed gas mentioned above shall first be collected in the collector 10a. The recovery device is UF with refrigerant 11a.

It is cooled to a temperature below the condensation temperature of Chiaria gas and not below the condensation temperature of Chiaria gas. Helium or argon is commonly used as Chiaria gas.

As shown in FIG. 2, since the condensation temperature is much lower than that of UF, the refrigerant temperature may be selected between the temperature obtained by a normal refrigerator and the temperature of liquid air. UF
Because it is a sublimable substance, it is cooled in the first recovery vessel and becomes a solid and precipitates. At this time, if the refrigerant temperature is chosen to be relatively low,
F2 also becomes solid and precipitates at the same time as UF.

In the present invention, at the same time as collecting the above-mentioned UF and F,
, are also collected in the collector. UF.

Since it is a solid, it is turned into particles in the collector and captured using the method described below. On the other hand, the Chiaria gas passes through the collector without being condensed, passes through the Chiaria gas exhaust pipe 13 and the pump 14, and
It is returned to Chiaria Gas Tank 2 and reused.

When a predetermined amount of UF, , UF, is collected in the collector 10a, the collection is continued by switching to the collector 10b. The recovery vessel 10a closes the entrance and exit to stop the refrigerant.Next, the heat medium 12a is supplied to the recovery vessel 10a, and the recovery vessel is heated to sublimate the UF.

One UF taken out from the recovery pipe 15 is stored in a cylinder or the like as a waste product.When operating one UF, the vapor pressure is higher than the UF, and the higher F sublimes earlier than the UF, so the temperature of the heating medium must be adjusted. It is possible to separate it from UF by. Alternatively, the F2 may be taken out from the collector at the same time as the UF, and then separated using another device. Can be reused. After the above operation, finally the collector 1
F is supplied from the F2 supply pipe 16 to the UF remaining in Oa to refluorize the UF.

UF is a relatively unstable compound and reacts with F2 to form UF. During the operation, the recovery vessel is heated with a heating medium to promote the reaction. After completion of refluorination of UF, UF
The UF taken out from the collection pipe 15 is stored as a product in a cylinder or the like.

The above series of operations are performed alternately in one recovery device 10a and 10b.

FIG. 3 is a sectional view showing the specific configuration of the recovery device 10a in this embodiment, and the recovery device 10b also has the same configuration as that in FIG. 3. The inside of the container is partitioned by baffle plates 22, and a filter 23 is provided on the downstream side. A jacket 25 for passing a refrigerant or a heat medium is provided on the outer surface of the container, and the outer periphery thereof is covered with a heat insulating layer 26.0 When carrying out the present invention.

In order to increase the cooling or heating effect, a refrigerant or heat medium may be circulated within the container using a vibrator or the like, or an electric heater may be provided instead of circulating the heat medium.

UF, , F, , UF, and Chiariagas times.

UF and F flow in from the inlet 21 of the collector and while flowing between the baffle plates, are cooled and deposited on the surface of the baffle plate or the inner surface of the collector. The UF is turned into particles and deposited on the baffle plate, but those that cannot be completely deposited are captured by the filter 23.

Uncondensed Chiaria gas exits the collector outlet 24.

As described above, according to this embodiment, UF, , UF, , F, and Chiaria gas can be reliably separated and recovered with a simple device configuration. Another advantage is that the recovered F2 and Chiaria gas can be reused.

FIG. 4 shows a modified example of the recovery device described above, which is characterized in that a nozzle plate 27 is provided in place of the baffle plate.
In this modification, the UF is
This has the effect of promoting particle formation and deposition of .

1''''UF, (7) dissociated substance'''UF, wo, undissociated +7) UF.

can be efficiently separated. Additionally, Chiaria gas added to UF easily UF.

It can be separated and reused. Also.

Since the solid "Up's" can be converted into gaseous UF, there is an effect that the material can be easily handled in the separation process.

〔Effect of the invention〕

As detailed above, according to the laser isotope separation apparatus of the present invention, separation of dissociated UF and undissociated UF,
Alternatively, it has an excellent practical effect of being able to efficiently separate these from chiaria gas.

[Brief explanation of the drawing]

Fig. 1 is a system diagram of an apparatus showing an embodiment of the present invention, Fig. 2 is a chart showing temperature-vapor pressure curves of UF, t'F, argon, and helium, and Fig. 3 is a diagram showing a recovery device of the present invention. FIG. 4 is a longitudinal sectional view showing a modification of the recovery device shown in FIG. 3. 1... UF, tank, 2... Chiaria gas tank,
3... Supply pipe, 4... Adiabatic expansion nozzle, 5... Irradiation window, 6... Selective excitation laser, 7... Dissociation laser,
8...Exhaust pipe, 10a, 10b-recovery device, l 1
a, 1 l b・=refrigerant, 12a, 12b”・heat medium, 15-UF, recovery pipe, 16...F, supply pipe, . Agent Attorney ±fJL Tomo・, 9- Ogawa Stress, -21, (, ′) ′・J No. 1 No. 20 Intensity (°C) No. 4

Claims (1)

[Claims] 1. By irradiating a mixed gas of uranium hexafluoride with an inert gas added as a carrier gas to selectively excite and dissociate the component of interest in the uranium hexafluoride. In the laser isotope separation device to be separated, a recovery device is provided for introducing uranium pentafluoride and fluorine, which are the substances produced in the dissociation, and a mixed gas of uranium hexafluoride, which is an undissociated substance, and chiaria gas, and , the recovery vessel has either a structure for depositing uranium pentafluoride, fluorine, and uranium hexafluoride, or a structure for condensing and collecting uranium pentafluoride, fluorine, and uranium hexafluoride, and , a laser isotope separation device characterized in that it is configured to discharge Chiaria gas to the outside of the recovery device. 2. The laser isotope separation apparatus according to claim 1, wherein two or more recovery units are installed and are configured so that they can be used alternately. 3. The recovery vessel described above shall be equipped with means for heating fluorine and uranium hexafluoride to a temperature that sublimates them, and
2. The laser isotope separation apparatus according to claim 1, further comprising means for supplying fluorine. 4. The above-mentioned recovery device separates and discharges the Chiaria gas,
2. The laser isotope separation apparatus according to claim 1, further comprising piping and a pump for supplying chiaria gas to be added to uranium hexafluoride. 5. The heating means is temperature-adjustable and has a function of heating to a temperature that sublimates fluorine and a temperature that sublimates uranium hexafluoride. The laser isotope separation device described in . 6. Laser isotope separation according to claim 5, wherein the recovery device is equipped with means for supplying the separated fluorine as fluorine for fluoridation of uranium pentafluoride. Device.