Procedure for processing uranium hexafluoride and device of implementing same

FIELD: metallurgy.

SUBSTANCE: procedure for processing uranium hexafluoride involves supply of the main stream of gaseous uranium hexafluoride into uranium-fluorine plasma generator, supply of an additional flow of gaseous uranium hexafluoride into an additional circuit to the uranium-fluorine plasma generator, forming of a cluster of uranium-fluorine plasma out of the primary and secondary streams of uranium hexafluoride at the entrance to the uranium-fluorine plasma generator. Then uranium-fluorine plasma flow is formed in the separation chamber of the magnetic separator, removal of the neutral atomic fluorine from the uranium-fluorine plasma flow, condensation of uranium, collecting of molten metallic uranium, formation of a bar of metallic uranium and output of the formed uranium bar. The precession of a cluster of uranium-fluorine plasma is performed along a conical surface in the skin layer by means of magnetic and/or gas-dynamic scanning of additional flow of uranium hexafluoride. A device for implementation of the said procedure is also suggested.

EFFECT: increased stability of the radio frequency discharge by improving the communication of radio frequency generator with the load - the flow of uranium-fluorine plasma of uranium hexafluoride.

7 cl, 3 dwg

 

The invention relates to the processing of uranium hexafluoride is one of the key products of the nuclear fuel cycle. The application of the invention is most preferable for the recovery of uranium and fluoride of uranium hexafluoride waste in the isotope U-235.

A method of refining of uranium hexafluoride (RF patent No. 2090510, publ. 20.09.97), including its interaction with water vapor at high temperature and subsequent separation of the solid and gas phases, and the interaction of uranium hexafluoride with water vapor is carried out in a plasma vapor outside the zone of discharge, the water vapor taken in excess, not to exceed 5% relative to the stoichiometric quantity, the specific energy consumption is not less than 0.5 kW·h/kg of uranium hexafluoride when processing time is not less than the 4.1·10-3from and after separation of the phases, the gas phase condense and rectification produce anhydrous hydrogen fluoride and the azeotrope of hydrogen fluoride water, thus to create a 5% excess of water vapor using the azeotrope of hydrogen fluoride is water.

The technology is based on the conversion of dump UF6plasma water vapor (H-HE-plasma) at stoichiometric or close to it the ratio UF6and (H-HE-plasma.

Achieved technical result:

- performance - 0.14-0.15 t UF6/h;

- power plasma reactor 0.26 MW;

- the molar ratio of (H-HE)/UF6=3-4;

the concentration of HF in the gas stream before entering the condenser - up to 88.5%;

the concentration of HF in the gas stream after the condenser - up to 95.4%;

- the release of fluoride into the target products (anhydrous HF and hydrofluoric acid) - 96-98%;

the content of fluorine in uranium oxides to 2%;

- average consumption - 1.7-1.9 kWh/kg UF6.

To date, I have found some disadvantages of this technology:

incomplete extraction of fluoride in anhydrous hydrogen fluoride (~90%);

- uranium oxides is acceptable, but inconvenient form of storage and especially the utilization of the actual dump uranium; in addition, optimization of the process from the point of view of maximum extraction of fluoride leads to deterioration of the physico-chemical properties of uranium oxides, preventing any use of a nuclear fuel cycle.

Known plasma-hydrogen concept of recycling waste uranium hexafluoride, in accordance with which the products of processing is anhydrous hydrogen fluoride and the molten uranium metal; the latter is much more in line with the needs and utilization, and storage - RF patent N 2120489 from 24.06.97. BI No. 29 from 20.10.98. The process is based on hydrogen recovery of uranium hexafluoride at high temperatures, is carried out in one processing unit and consists of four sequence is nutrient-parallel stages. The first stage consists in the recovery of uranium from uranium hexafluoride to elemental uranium or to the lowest of uranium fluorides. This intermediate goal is achieved by the excitation of the electric discharge in the stream of the mixture of gaseous uranium hexafluoride with hydrogen, the mixture UF6+H2turns into uranium-formotorola plasma containing a mixture of uranium atoms, hydrogen and fluorine molecules of uranium fluorides, fluorine, hydrogen, positively and negatively charged ions and electrons. If during this operation the temperature of the plasma is at atmospheric or close to it the pressure of 6000 K, the main part of the uranium contained in the form of atoms U, i.e. in the gas phase, the full recovery of uranium.

In the second stage of the reduction products of uranium hexafluoride transfer in the condensed phase, in which the slow recombination processes, and the process of recovery of uranium continues to receive liquid uranium. For this uranium-formotorola plasma obtained at the first stage, is directed to a bath of molten uranium tetrafluoride, which is obtained as follows. Download tetrafluoride uranium placed in a cooled cylindrical shell, transparent to the frequency of the electromagnetic field, resistant to the corrosive action of molten fluorides of uranium. The shell specified in the insert into the inductor frequent the spas generator coaxially with the discharge chamber, where get (U-F-H)-plasma. The flow of the plasma interacts with the surface loading of uranium tetrafluoride and melts the top layer last. The inductor serves frequency voltage; zone melt tetrafluoride uranium interacts with frequency field, causing the load rapidly heated by direct induction heating and melting. On the surface of the melt UF4when interacting with (U-H-F)- plasma condensation occurs uranium and lower fluorides of uranium; occurs simultaneously disproportionation of the latter in accordance with the equations:

As the reactions (1-3) in the condensed phase is an intensive mass transfer, due to the correlation of the melting points and densities of the resulting products. The melting point of uranium - 1133°C, density - 19.04 g/cm3; melting point of the uranium tetrafluoride - 1036°C, the density is 6.43-6.95 g/cm3; the melting point of uranium TRIFLUORIDE - 1427°C, density 8.95 g/cm3. First melt tetraploid uranium, and the uranium, last TRIFLUORIDE uranium. Due to the large differences in the density of uranium and fluoride uranium occurs the precipitation of the uranium and the emergence of uranium fluorides in the surface layer exposed to the hydrogen plasma is s, and tetraploid uranium will float in the molten uranium TRIFLUORIDE.

Thus, within a few minutes under the action of the plasma flow and direct frequency heating is a full recovery of uranium from uranium hexafluoride and the initial load of uranium tetrafluoride. The decline last continuously fill fluorides of uranium (U-F-H)-plasma. While fluorine is bound in gaseous hydrogen fluoride, which evaporates from the zone of recovery of uranium. To improve the stability of the RF discharge improve communication between the radio frequency generator with load - flow plasma by introducing an additional power supply and adapter, which can be used in the waveguide, the inductor, the external electrodes, internal electrodes, etc.

The third stage is carried out simultaneously with the first two, the removal of liquid uranium from the bottom of the reactor shell and pouring it into a cooled mold.

The fourth stage is carried out simultaneously with the first three, the removal and collection of the second commercial product anhydrous hydrogen fluoride. Conclusion gaseous hydrogen fluoride passes through the filtration module comprising a multilayer recycled metal items not passing micron and submicron powders and aerosols, and thus about especiauy process safety from uncontrolled penetration pyrophoric product outside of the production area.

Next, the flow of anhydrous hydrogen fluoride, purified from the dispersed phase, condensed, collected in liquid form in the shipping container and send for sale or for feeding electrolysis baths to obtain elemental fluorine. A significant disadvantage of this process is the low rate of reactions (1-3).

The alternative to this process - a method and apparatus for the processing of uranium hexafluoride, as claimed in the patent of Russian Federation №2216390, publ. 20.11.2003, a similar application WO No. 97/34684. Stream gazoobraznogo of uranium hexafluoride UF6enter in a microwave or radio frequency plasmatron with adapter to increase the stability of the discharge pressure increase, which requires to increase the communication radio-frequency generator to the load (inductor for RF induction plasmatron; a waveguide for microwave plasmatron), in which the feedstock is converted into a stream of uranium-fluorine plasma with a temperature of about 4000 K. When using RF induction discharge plasmatron is made of longitudinal water-cooled copper sections, separated by dielectric inserts, transparent to electromagnetic radiation and the inductor RF generator. This torch next to simplify called metal by the plasma torch. This title reveals how it works: the frame of the implementation of the eh of a nonmagnetic metal, hermetic dielectric inserts allow free penetration of the magnetic field inside the plasmatron.

When using a microwave discharge plasmatron made in the form of a metal pipe of non-magnetic metal, in which an angle of 90° is inserted one or more waveguides, coming from the magnetron of the microwave generators.

The flow of uranium-fluorine plasma into the chamber separation, in which it compresses the magnetic field intensity of about 0.1 Tesla, created by the magnet. To achieve a given degree of ionization of uranium in the flow of uranium-fluorine plasma outside of the flow set antenna electronic cyclotron resonance. This antenna according to the electron plasma extra energy they spend on the ionization of atoms of uranium, while the fluorine atoms remain neutral. This atomic fluorine pumped from the stream of the uranium-fluorine plasma dry pumps, creating, thus, a stream of fluorine. The flow of ions of uranium compresses the magnetic field of another magnet, when this occurs, the uranium beam downward.

The flow of uranium is directed to a bath of molten uranium in a graphite crucible, which, when it is full, remove and simultaneously replace it with the rotary device other crucible without breaking the vacuum.

The camera division was divided into three zones pereg rodomi, with openings in the first zone maintained pressure in the range of 10 to 50 PA, the second 5-20 PA, in the third 2-10 PA. Each of these zones is equipped with individual pumps for pumping of fluoride.

Apparatus for the conversion of the flow of uranium hexafluoride in the flow of condensed gaseous uranium and fluorine included:

- radio-frequency or microwave generator uranium-fluorine plasma and ion flux uranium;

means for selective ionization of uranium plasma components;

means to accelerate the flow of uranium-fluorine plasma to supersonic speeds;

means for generating a magnetic field, jaws charged component plasma (ions of uranium);

means for removing uncharged components (fluoride) from the stream of the uranium-fluorine plasma, objetos magnetic field;

means for outputting the molten uranium.

The flow of uranium-fluorine plasma was injected from the plasma torch at the camera separation through the nozzle openings in the partitions correspond to the diameters of the primary stream of the uranium-fluorine plasma and the secondary flow of uranium ions. The diameter of the primary and secondary flows gradually increased along the axial coordinate of the process, therefore, the diameters of the holes in the walls also increased, in order not to create resistance to the downward flow of uranium material and to provide the pressure drop at which the movement in the axial coordinate system.

In order to keep the flow of uranium ions at the center of the chamber in each of the three compartments of the apparatus was placed inductors, fed from a separate power source that generates a magnetic field. The diameter of the nozzle at the exit of the plasma torch reaches 0.03 m; this is sufficient to maintain the chamber pressure of about 2 kPa to provide the desired flow rate of the uranium-fluorine plasma. This thread is exiting the nozzle into the chamber expands and, in accordance with the Joule-Thomson has a tendency to self-cooling. Therefore, the second purpose of the above-mentioned inductors - induction heating of the plasma flow, which compensates the initial cooling and allowing to maintain the temperature in the plasma flow at a level sufficient to ensure that the uranium was in the form of ions U+1.

The flow of ions of uranium held by the Central chamber of a magnetic field intensity of about 0.1 Tesla. Thus, in the camera to make a separation of the components of the uranium-fluorine plasma and create two material flow: the flow of atomic fluorine, which is sent for recycling, and the flow of uranium ions, which promote in a magnetic field in the collector is filled with molten uranium. The flow of uranium discharged from the chamber in the form of a melt which is poured into moulds. When performance setup 17.75 kg UF6/h are 12 kg U/h; when this occurs, p is the current fluoride 5.7 kg/h

The disadvantage of this solution is that the radio frequency discharge (frequency range 0.5-14 MHz) unstable burning in electronegative gas, which is uranium hexafluoride, UF6or uranium-fluorine plasma at pressures of about 4 kPa and above. The lower the frequency of the radiofrequency generator, the lower the permitted pressure range, in which the discharge is lit steadily. At the same time, the high frequency power source power increases with decreasing frequency. In addition, the electric discharge such gases as UF6, accompanied by a strong cooling of the plasma due to the endothermic effects of decomposition UF6and its parts.

Due to these limitations, any technological and metallurgical apparatus, equipped with a high-frequency induction plasma torches have limitations on pressure, frequency and resource.

To remove these limitations, you must supply the plasmatron additional device, which contributes to the discharge of additional power from an auxiliary power source, which can be used to build more reliable channel power plasma reactor.

Microwave discharge in uranium hexafluoride, UF6(frequency 900 and 2450 MHz) relatively steadily lit even when the pressure is close to atmospheric. However, a disadvantage of the microwave is Otrada is a relatively low temperature discharge plasma (~5000 K at atmospheric pressure), what limits while maintaining a stationary mode in which the fully ionized uranium and fluorine - mostly neutral.

The practical use of cyclotron resonance of electrons for ionization of uranium in uranium-fluorine plasma is difficult, because the initial temperature of the uranium-fluorine plasma 4000 To low not only for the ionization of atoms of uranium, but also for the complete dissociation of uranium fluorides. In addition, the use of antennas inside the device too complicates the design.

In connection with the above processing of uranium hexafluoride are encouraged to use the radio frequency discharge, in order to increase the stability of the radio-frequency discharge with increasing pressure is to install additional circuit with the auxiliary power supply and adapter, for example, as in patent No. RF N2120489. But this solution does not fully ensures the stability of the radio-frequency discharge.

The technical result, which aims invention is to further increase the stability of the radio frequency discharge by improving communication of the radio-frequency generator with load - flow-uranium-fluorine plasma, which leads to the expansion of the functional and technological capabilities of the proposed technical solution.

To achieve the specified result of the method of processing ODI of uranium hexafluoride including the flow of the main flow of gaseous uranium hexafluoride to a generator uranium-fluorine plasma, made in the form of frequency induction plasma torch, submitting an additional stream of gaseous uranium hexafluoride in the secondary circuit to the generator uranium-fluorine plasma, the formation of a cluster of uranium-fluorine plasma of an additional flow of uranium hexafluoride at the entrance to the generator uranium-fluorine plasma, forming a stream of the uranium-fluorine plasma in the separation chamber of a magnetic separator, the destruction of neutral atomic fluorine from the stream of the uranium-fluorine plasma, condensation and collection of the melt uranium in the "device type " cold crucible", the formation of uranium metal ingot, while carry out the precession of the cluster uranium-fluorine plasma on the conical surface in the skin layer by magnetic and/or gas-dynamic scan additional flow of uranium hexafluoride.

Furthermore, the magnetic scanning is carried out by applying a magnetic field. Gas-dynamic scanning is carried out by tangentially directed an additional flow of uranium hexafluoride.

The skin layer is formed at the level of the high voltage coil of the inductor of the plasmatron.

Also, an apparatus for processing of uranium hexafluoride, comprising means for introducing the main thread hexa is torida uranium, connected to the generator uranium-fluorine plasma, made in the form of frequency induction plasma torch connected to the camera separation of uranium-fluorine plasma, made in the form of a magnetic separator, which is connected to pumping means fluorine, and in the lower part with means for collecting and conclusions of molten uranium, while to the upper part of the plasma generator connected to an additional circuit consisting of additional power supply, adapter, nozzles for introducing an additional flow of uranium hexafluoride and means for gas-dynamic and/or magnetic scanning an additional flow of uranium hexafluoride.

The tool for magnetic scanning an additional flow of uranium hexafluoride is made in the form of an annular solenoid.

The tool for gas-dynamic scan additional flow of uranium hexafluoride performed as mounted tangentially to the lateral surface of the nozzles of the nozzle input of uranium hexafluoride.

In the figure 1 and 2 shows schematically an embodiment of a device for the processing of uranium hexafluoride.

The device consists of a camera division 1, made in the form of a magnetic separator and separated by partitions 2 into three zones I, II, III. In partitions 2 with holes 3, forming streams of uranium-fluorine plasma. The inductor is 4 magnetic separator is connected to the power source 5. Each zone camera separation is connected with the nozzles for the removal of fluoride with 6 pumps (figure not shown). Generator uranium-fluorine plasma 7 is made in the form of frequency induction plasma torch, which is a tube made of metal material. The inductor 8 is connected to the main power supply 9 - radio frequency generator. The plasma torch 7 is connected with the camera division 1 nozzle 10. In the upper part of the plasma torch is located nozzle 11 connected to the adapter 12 is connected to the auxiliary power supply 13. The main flow UF6served by pipeline 14 in the plasmatron 7 through the hole in the nozzle 11. Additional flow UF6served by pipeline 15 in the adapter 12 is installed through the nozzle 27 made of a nonmagnetic material. For magnetic scanning the specified thread on the adapter has an annular solenoid 28 In the bottom of the camera division 1 is the outlet 16 for collecting molten uranium metal in the "device type " cold crucible" 17. The inductors 18 "cold crucible" is connected to the power source 19. Formed the uranium ingot 20 is pulled through the device 21.

The magnetic field generated in the camera division 1, conventionally shown by lines 22, the magnetic field holds the plasma flow uranium 23 at the center of the camera 1.

The figure 2 depicts the implementation of the upper part of the device.

In the upper part of the plasma torch 7 form a cluster uranium-fluorine plasma 24, at the level of the first high voltage coil of the inductor 8 is formed in the skin layer with the outer limit of 25, which is at a distance of approximately half the inner radius of the plasma generator 7. Further, in the plasma torch is formed by the flow of uranium-fluorine plasma 26.

The figure 3 shows the location of the skin layer in the cross section at the high voltage level of the first spiral inductor of the plasma torch 8.

In the description of the invention using terms understand the following.

The cluster uranium-fluorine plasma - the plasma flow generated from the secondary and primary flows of uranium hexafluoride in the upper part of the plasma torch to the first spiral inductor 8.

The skin layer is a layer which is separated ~95% power absorbed by the host environment from the inductor through the so-called skin effect.

The skin effect and surface effect damping of electromagnetic waves as they penetrate deep into the conducting medium (the attenuation factor - α), in which an alternating current over the cross section of the conductor is not distributed uniformly, but mainly in the surface layer (skin layer). The higher the frequency of the electromagnetic field ω and the more magnetic permeability µ of the conductor, the strength is her vortex electric field in this layer, generated alternating magnetic field. The higher the conductivity of the conductor (σ), the greater the current density and dissipation in this layer capacity.

At a depth of x=δ=1/α the amplitude of the electromagnetic wave decreases e times. This depth is conventionally taken for the thickness of the skin layer (Physical encyclopedic dictionary, M.: Great Russian encyclopedia, 1995).

Magnetic scanning tightening the flow of uranium-fluorine plasma due to the superposition of the magnetic field with the aid of a ring solenoid 28.

Gas-dynamic scan - twisting thread uranium-fluorine plasma due to the tangential entry of an additional stream of the uranium-fluorine plasma in the nozzle 27 additional circuit.

Precession is the movement of the cluster uranium-fluorine plasma on the surface of a cone, the base of which is the skin layer.

This invention is based on the fact that the radio frequency power generator 9 is not around the pipe section of the plasma torch 7, and in the skin layer, see figure 3. Therefore, the flow of uranium-fluorine plasma generated in the form of cluster 24 at the entrance to the plasma torch, should be directed not at the center, and in the skin layer, the outer radius of which is approximately equal to half the radius of the plasma torch. Accounting for the presence of the skin layer means that the additional flow of uranium hexafluoride must be initially twisted to the formed cluster is overal movement, describing a conical surface at the base of which lies the skin layer, the so-called precession. This can be achieved by magnetic scanning flow by installing an annular solenoid 28 on the secondary circuit. Also, the additional flow of uranium-fluorine plasma may be initially spun by gas-dynamic scan due to the tangential entry into the nozzle 27. Can be applied magnetic and gas-dynamic scan together. By mixing the two streams of uranium hexafluoride formed a cluster uranium-fluorine plasma 24. For each device must be made in the calculation of the required parameters: flow rate, magnetic characteristics, etc. In the address direction of flow of uranium hexafluoride increases the stability of the connection load - induction discharge.

The device operates as follows.

Both sources (radio-frequency generator 9 and the auxiliary generator 13) include at the same time, serves cooling in all refrigerated items installation: metal torch 7, the nozzle 11 and 27 and other Heat supply piping UF6to avoid condensation of the raw material. Then include the submission of additional flow UF6in the nozzle 27 and generate through the adapter 12 auxiliary flow (U-F)-plasma; the plasma flow transport who enjoy metal plasma torch 7, where is served the main flow UF6and the inductor 8 of the radio-frequency generator 9 is applied radio frequency voltage. Radio frequency electromagnetic field freely penetrates the metal of the plasma torch through the incisions. In metal-plasma torch occurs RF induction discharge, supported auxiliary flow (U-F)-plasma, which makes a precession around the center of the plasma torch to ring the skin layer and enhances the interaction of the generator with the load.

Perform additional path can be different, for example:

- if the main power supply using a generator of radio frequency induction (U-F)-plasma 9, the additional circuit can be accomplished by redistribution of vibrational energy through two channels: channel through the torch electrode and the induction channel;

- if the main power supply using a generator of radio frequency induction (U-F)-plasma 9, the additional circuit can be performed using as an extra power source 13 arc plasmatron;

- if the main power supply using a generator of radio frequency induction (U-F)-plasma 9, the additional circuit can be performed using the receiving extra power supply 13 of the microwave plasma torch, working on UF6.

Next, the flow of (U-F)-plasma served in the magnetic separator 1 for processing:

serial passage sections I, II, III, in which the through hole is removed fluorine, and at the end of the chamber dividing the stream of nearly pure uranium plasma exits through the hole 16 and is collected in the form of molten uranium metal in the device 17, known as the "cold crucible" /see I.N.Toumanov Plasma and High Frequency Processes for Obtaining and Processing Materials in the Nuclear Fuel Cycle. The 2nd Edition, reprocessed, supplemented. N.Y., Nova Science Publishers, 2008, 660 p.p./. "Cold crucible" is inside of the inductor frequency generator 18. The molten uranium in a "cold crucible" create simultaneously with the beginning of the actual process of recovery of uranium from uranium hexafluoride: for the "cold crucible" pre-put some amount of uranium and melted it, feeding frequency voltage to the coils of the inductor 18 from frequency power source 19.

The molten uranium pressed in a magnetic field "cold crucible" and almost does not contact with the water-cooled copper profiled tubes "cold crucible". In the bottom of the "cold crucible" mounted device for the extrusion of uranium ingot 21.

For the formation of molten uranium use relatively low frequency 2400-2500 kHz. At this frequency, the electromagnetic force is almost full the capacity to press the molten uranium from the walls "cold crucible". As a result of extraction in the upper part of the melt is formed meniscus 29, in which a damping of them changes the power input to the melt. Due to these phenomena wall "cold crucible" experience less stress and improve the quality of the uranium ingot pulling from a "cold crucible". Purity extruded uranium ingot chemical impurities is determined, thus, the purity of the uranium hexafluoride. The residual content of fluorine in uranium is ~10-4% the weight.

In an example embodiment of the invention consider a scheme where additional circuit consisted of the auxiliary power supply 13 - microwave generator connected to the waveguides with a plasma torch 7.

Was used rectangular waveguide for transmitting electromagnetic energy from the microwave generator, which is joined at right angles with a circular waveguide, which serves an additional stream of gaseous UF6. In docking place is this fashion - transformer electromagnetic waves H01the wave of H11. A circular waveguide is both microwave plasmatron working on an additional stream of gaseous UF6supplied through the pipe 15. Dielectric insert (sealer-junction)made of aluminum oxide, the section is no microwave generator and a microwave plasma torch.

The installed capacity of the radio frequency generator 9-100 kW, oscillatory power - 25-60 kW, the frequency of 5.25 MHz. The temperature of the cooling water of metal-dielectric discharge chamber, flange, supply pipes was 73°C. enter the primary flow UF6was 9.2-17.6 kg/h

The power of the microwave generator (U-F)-plasma ~5 kW, the frequency of 2.45 GHz. Standard rectangular waveguide had a cross section of 90×45 mm; such a waveguide is convenient to go to the round waveguide, which, in turn, is a transport pipe (U-F)-plasma for mating with metal tube of the plasma torch. Consumption UF6in the round waveguide support in the range of 1.2-2.3 kg/h Forced precession of the auxiliary plasma flow around the ring and the skin layer was performed using magnetic scanning. For this purpose, a circular waveguide has established an annular solenoid.

The pressure in the metal tube of the plasma torch was 41-83 .8 kPa. Lowering the frequency of 5.25 MHz to 1.76 MHz is not accompanied by a decrease in the stability of the discharge in UF6.

The calculations showed that when performance 76 kg UF6/h receive 51.4 kg U/h; when this occurs the flow of fluorine 24.6 kg/h: if this performance ~17.1 kg fluoride/h pumped from zone (I), ~5.97 kg fluoride/h pumped from the zone (II), ~1.53 kg of fluorine/h pumping of h is HN (III).

Thus, the following occurs.

1. Increases the stability of the RF induction discharge in uranium hexafluoride (and other strongly electronegative gases) for pressures up to at least ~102kPa.

2. It is possible to obtain flow (U-F)-plasma to use as power sources more powerful frequency generators lower frequency (0.3-0.44 MHz etc).

3. With the introduction of metal plasma generator frequency generator additional address power flow has the possibility of changing the quantitative ratio of the primary and secondary flows (U-F)-plasma in a wide range: from the power level required for simple discharge ignition and stabilization to comparable flows.

1. The method of processing of uranium hexafluoride, including the flow of the main flow of gaseous uranium hexafluoride to a generator uranium-fluorine plasma in the form of frequency induction plasma torch, submitting an additional stream of gaseous uranium hexafluoride in the secondary circuit to the generator uranium-fluorine plasma, the formation of a cluster of uranium-fluorine plasma from the primary and secondary flows of uranium hexafluoride at the entrance to the generator uranium-fluorine plasma, forming a stream of the uranium-fluorine plasma in the separation chamber of a magnetic separator, UDA is the group of neutral atomic fluorine from the stream of the uranium-fluorine plasma, condensation of uranium, collecting molten uranium metal, the formation of uranium metal ingot and the conclusion of the formed ingot uranium, while implementing the precession of the cluster uranium-fluorine plasma on the conical surface in the skin layer by magnetic and/or gas-dynamic scan additional flow of uranium hexafluoride.

2. The method according to claim 1, characterized in that the magnetic scanning is carried out by imposing a magnetic field.

3. The method according to claim 1, characterized in that the gas-dynamic scanning is carried out by tanzenziale additional directional flow of uranium hexafluoride.

4. The method according to claim 1, characterized in that the skin layer is formed at the level of the high voltage coil of the inductor of the plasma torch.

5. Device for the processing of uranium hexafluoride, comprising means for supplying a main flow of uranium hexafluoride connected to the generator uranium-fluorine plasma, made in the form of frequency induction plasma torch connected to the camera separation of uranium-fluorine plasma, made in the form of a magnetic separator, which is connected to pumping means fluorine, and in the lower part with means in the form of a "cold crucible" for condensing and collecting the molten uranium metal, forming an ingot of metallic uranium and output the formed ingot uranium, however, ve is chna part of the plasma generator connected loop, consisting of additional power supply, adapter, nozzle, means for introducing an additional flow of uranium hexafluoride for forming from it together with the main flow of uranium hexafluoride at the entrance to the generator cluster uranium-fluorine plasma and means for gas-dynamic and/or magnetic scanning an additional flow of uranium hexafluoride.

6. The device according to claim 5, characterized in that the means for magnetic scanning an additional flow of uranium hexafluoride is made in the form of an annular solenoid.

7. The device according to claim 5, characterized in that the means for gas-dynamic scan additional flow of uranium hexafluoride performed as mounted tangentially to the lateral surface of the nozzles of the nozzle input of uranium hexafluoride.



 

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2 tbl, 2 dwg, 3 ex

FIELD: metallurgy.

SUBSTANCE: processing method of nitric-acid solution of regenerated uranium involves uranium (VI) extraction with tributyl phosphate in organic diluter; flushing of extract with nitric-acid solution and re-extraction of uranium. At that, removal of technetium from uranium is performed by shifting technetium (VII) to non-extracted quadrivalent state in flushing zone of extraction cascade with the use of flushing solution containing 0.1-0.2 mol/l of carbohydrazide and 0.05-0.15 mol/l of nitric acid. Extract is flushed at the ratio of flows of organic and water phases, which is equal to 10-15. Method can be implemented in two versions. As per the first version, used flushing solution is supplied to feed stage of extraction cascade and technetium is removed to raffinate. As per the second version, used flushing solution is a separate flow from which uranium is extracted by contact with flow of fresh extractant; organic phase is connected to initial uranium extract prior to supply to flushing zone, and technetium is removed to separate product the volume of which is 5 times less than the raffinate volume.

EFFECT: increasing separation efficiency of uranium and technetium.

9 cl, 2 dwg

FIELD: metallurgy.

SUBSTANCE: procedure consists in stage of introduction of complex forming compound to contact with water medium containing said actinoid and one or more lanthanides. Also, the said complex forming compound in not complexated state is not retained with the said membrane and is capable to form complex with said actinoid containing the said element and at least two molecules of the said complex forming compound, also, complex is capable to be retained with the membrane. Further, there is performed the stage of water medium passing through the membrane for formation of filtrate containing water effluent depleted with said actinoid from one side, and retentate containing the said complex.

EFFECT: avoiding membrane clogging at filtration.

13 cl, 5 dwg, 1 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: present invention relates to substrate material for complex formation and selective extraction of americium, plutonium, uranium or thorium in their cationic form, which is para-tert-butyl-calix[6]arene of formula (IIA), where R'1 R'3 and R'5, which are identical or different, each separately denotes: (i) a linear or branched C1-6alkyl deposited on a substrate, wherein one of the groups R'1 R'3 and R'5 in the compound of formula (IIA) is a group (ii); (ii) spacer-substrate, where the space is a divalent radical selected from a group comprising aryl(C1-6alkyl)aryl; and the substrate is selected from a substrate which is a copolymer of chloro- or bromo-methylstyrene and divinylbenzene. The invention also relates to a liquid membrane deposited on a substrate for complex formation or selective extraction of americium, plutonium, uranium or thorium in their cationic form, containing para-tert-butyl-calix[6]arene of formula (IA) or (IB), which is dissolved in an organic solvent, having boiling point higher than 60°C and absorbed on a substrate, which is epoxy resin, where R1, R3 and R5, which are identical or different, each separately denotes: (i) a hydrogen atom, (ii) a linear or branched C1-6alkyl.

EFFECT: obtaining novel materials.

7 cl, 8 ex, 2 tbl

FIELD: metallurgy.

SUBSTANCE: procedure consists in production of sample containing uranium and silicon dioxide, in treatment of sample containing uranium and silicon dioxide and in production of material containing dissolved uranium and silicon dioxide. Also, material contains SiO2 over or equal to 100 mg/l. Further, dissolved uranium is extracted from material using at least one strong base anion-exchanging resin of macro-reticular structure. There is obtained uranium containing product in combination with strong-base anion-exchanging resin of macro-reticular structure. Further, uranium containing product is eluted and extracted from combination with strong-base anion-exchanging resin of macro-reticular structure.

EFFECT: increased efficiency of uranium extraction from mediums with high contents of silicon dioxide.

9 cl, 3 tbl, 1 ex

FIELD: metallurgy.

SUBSTANCE: halogenation of initial raw material is performed at heating with gaseous brome so that calcium bromide and iron bromide (II) is formed. Then, oxidation of calcium bromide is performed with tenfold excess amount of oxygen of the stoichiometrically required one at temperature of >742°C with extraction of calcium oxide and gaseous brome. Gaseous brome is returned to the process cycle to halogenation stage of initial calcium-containing raw material.

EFFECT: extraction of calcium oxide and recycling of the reagent used at decomposition of calcium-containing mineral raw material.

5 cl, 2 dwg, 3 ex

FIELD: metallurgy.

SUBSTANCE: procedure consists in charging and melting raw material, coke, fluxes and manganese containing additives, in blasting hydrocarbon substitutes of coke into blast-furnace hearth and in tapping iron an titanium slag. Manganese containing additive is introduced at amount ensuring contents of manganese not less, than 1 % in iron and ratio of manganese to vanadium 1.0-1.3; also contents of carbon in iron is maintained within ranges 4.5-5.2 % by blasting hydrocarbon gas, and ratio of calcium oxide to titanium dioxide in slag within ranges 0.3-0.7 is maintained by introduction of calcium carbonate.

EFFECT: increased extraction of chromophore into iron, reduced losses of iron with slag, elimination of forming titanium oxy carbonitrides, production of commodity titanium slag suitable for production of pigment.

3 cl, 3 tbl, 1 ex

FIELD: metallurgy.

SUBSTANCE: invention concerns metallurgy field and can be used for receiving of metals from its oxides and also silicon from its oxide. Method of receiving metal or silicon consists in its oxides reduction. Reduction is implemented by means of treatment by electronic beam of powder of metal oxide or silicon oxide on the surface of metal melt or silicon melt. Process is implemented at current density in beam 5-12 mA/mm2, accelerating potential 15-35 kV and in vacuum 10-4-10-5 mm of mercury.

EFFECT: reduction of electric power consumption and receiving of metal or silicon in the form of solid ingot, nonpolluted by admixtures.

3 cl, 1 dwg, 8 ex

FIELD: ferrous and non-ferrous metallurgy; methods of production of iron, cobalt or nickel.

SUBSTANCE: the invention is pertaining to the field of ferrous and non-ferrous metallurgy, in particular, to the method of production of iron, cobalt or nickel. The method provides for a mixing of oxides of the produced metals and halogenides of the metals, realization of the process in the container made out of the metal corresponding to the being reduced oxide, aging at heating and separation of products. Process is conducted in the installation, the reactionary volume of which is insulated from a contact to the aerosphere. The offered method allows to produce metals in the form of the individual crystals free from impurities, for example from carbon, and may be used both in a laboratory practice, and in a large-scale production.

EFFECT: the invention ensures production of metals in the form of the individual crystals free from impurities, for example carbon, and may be used both in a laboratory practice, and in a large-scale production.

2 dwg, 1 tbl, 1 ex

FIELD: non-ferrous pyrometallurgy, in particular, small-scale or average-scale production of matte or metal with the use of mobile equipment in poorly settled regions with non-existent or weakly developed infrastructure.

SUBSTANCE: method involves melting with the use of oxygen-containing blast gas; converting; depleting slag in gasifier; reducing gases from melting process and converting with hot gases from gasifier. Oxygen-containing blast gas used is exhaust gas of energetic gas turbine unit operating on natural gas or gas generating gas from coal gasification. Gas used for gas turbine unit is gas generating gas from bath coal gasification produced on slag depletion. Flow line has melting bubbling furnace, converter, gasifier for slag depletion, gas turbine unit with system of gas discharge channel connected through branches with tuyeres of melting furnace, converter and gasifier. Each of said branches is equipped with pressure regulator and flow regulator.

EFFECT: reduced costs for performing method owing to employment of mobile equipment.

3 cl, 1 dwg, 1 ex

FIELD: copper metallurgy; reduction of copper from sulfide compounds in concentrates, mattes and other materials.

SUBSTANCE: proposed method of reduction of copper from sulfide compounds includes reduction of copper by sulfide sulfur; sulfide copper material is charged with caustic soda at the following ratio: 1 : (0.5-2.0) and is heated at temperature 400-650°C for 0.5-3.5 h. Reduction of copper from its sulfide compounds may be performed at temperature below melting point at exclusion of forming of gaseous sulfur-containing products.

EFFECT: enhanced efficiency.

1 tbl, 7 ex

The invention relates to the field of processing of sulphide concentrates and can be used in chemical technology with sulfuric acid

The invention relates to a method and a heating unit that is used to obtain volatile metals from their sulphide

FIELD: copper metallurgy; reduction of copper from sulfide compounds in concentrates, mattes and other materials.

SUBSTANCE: proposed method of reduction of copper from sulfide compounds includes reduction of copper by sulfide sulfur; sulfide copper material is charged with caustic soda at the following ratio: 1 : (0.5-2.0) and is heated at temperature 400-650°C for 0.5-3.5 h. Reduction of copper from its sulfide compounds may be performed at temperature below melting point at exclusion of forming of gaseous sulfur-containing products.

EFFECT: enhanced efficiency.

1 tbl, 7 ex

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