The method of conversion of uranium hexafluoride to uranium metal and anhydrous hydrogen fluoride and a device for its implementation
(57) Abstract:The invention relates to a process and apparatus registration processing of uranium hexafluoride with different contents of nuclide U-245 on uranium metal and anhydrous hydrogen fluoride. The application of the invention is most preferable for the processing of uranium hexafluoride with otvajnym content nuclide U-235. The method consists of four series-parallel stages. In the first stage, the uranium hexafluoride is reactivated by hydrogen to uranium and lower fluorides of uranium in plasma or oxy-fuel apparatus and direct the high temperature uranium-pterodactly flow on the surface of the boot tetrafluoride uranium in metal reactor, placed in the inductor high frequency generator and transparent to the electromagnetic field. Starting the second stage in which the uranium is completely reduced to the elemental state and he settles in the lower part of the metal of the reactor. The third stage is the conclusion of uranium through the S-shaped pipe, one end of which is mounted in the bottom of the metal reactor and the other end is over-cooled mold for pouring liquid uranium. Irectional by Stripping for the regeneration of the filter elements. At this stage of technological device deduce the second commercial product is anhydrous hydrogen fluoride. A device for implementing the above method comprises a gas-phase reactor coupled with a generator of high temperatures, metal reactor, powered by a high-frequency generator, the output system of liquid uranium and anhydrous hydrogen fluoride with the environmental cleanup of the gas exhaust. 2 C. and 15 C.p. f-crystals, 2 Il. The invention relates to a process and apparatus registration processing of uranium hexafluoride with different contents of nuclide U-235 in uranium metal and anhydrous hydrogen fluoride. The application of the invention is most preferable for the processing of uranium hexafluoride with natural or otvajnym content nuclide U-235.The scope of this invention is very wide, but of particular relevance at the present time is the problem of processing waste uranium hexafluoride, obtained in the process of separation of isotopes of uranium in centrifuges or laser technology. When 90%-enriched uranium for nuclide U-235 from each ton UF6received in the separation process, 0.9 t UF6comes on Talnoe field. The process nakoplenie snaa the relevance of the problem of waste uranium hexafluoride is determined by environmental and economic problems. Environmental problems have arisen from potential and actual hazards storage of the vast mass of volatile radioactive fluoride product in steel cylinders under the open sky. Economic problems are defined so that actually "died" huge stocks of fluorine - product, which has become scarce even before the collapse of the USSR, but after its collapse, the majority of mines, where he mined fluorite, remained in the countries of the so-called Near abroad, with all the consequences. In each ton dump UF6contains 0,324 t fluorine; the cost of this when fluorine was formed in the USSR, the system of prices is actually defined by the capital and operating costs to remove it from UF6. Uranium is also great value as a component of some fuel compositions in nuclear reactor construction, as a component of precision alloys and as an alloying additive to some alloys for General purposes. In addition, worth mentioning and high operating costs for the maintenance and expansion of the dump fields, including necrosis price of land and the cost of future reclamation.A method of refining uranium hexafluoride to uranium metal, cotoran of uranium hexafluoride with hydrogen is carried out in flame machine with hot and cold walls. The heat required for the process, generates directly in the zone of reaction due to the flame reaction. The process of generation of heat is described by the equation exothermic reaction
1/2H2+ 1/2F2------> HF, dH = -271,8 kJ. (1)
Recovery of uranium to UF4is described by the equation
UF6+ H2------> UF4+ 2HF, dH = -288 kJ. (2)
The second operation - calcitonine recovery of uranium from uranium tetrafluoride by the equation
UF4+ 2Ca-----> U + 2CaF2, dH = -577,7 kJ. (3)
The process metallothermic melting is carried out in a mine or in a crucible lined calcium fluoride.When this process 1/3 of fluorine spent on obtaining uranium hexafluoride, is utilized in the form of anhydrous hydrogen fluoride; 2/3 of fluorine transferred in a relatively low slag - calcium fluoride containing some amount of uranium.Both operations, especially the metallurgical treatment, are labor intensive, the cost of manual labor, loss of uranium and fluorine.Closest to the present invention are a method and apparatus for the direct production of elemental uranium from uranium hexafluoride. The way is generated in an electric arc plasma torch, angle 90oto the last. The molar ratio of hydrogen/fluorine = 3: 1. The conditions of mixing are selected so that the molecules of uranium hexafluoride and hydrogen were completely dissociatively and partially ionized. Homogeneous gas mixture of U-F-Ar-He-H passes through the Laval nozzle, extending part, which is the rate of cooling of a mixture of 108- 109K/C. the Pressure at the outlet from the chamber of the plasma torch and at the entrance to the Laval nozzle 3 is atmospheric pressure at the exit of the nozzle 85 Torr, the temperature in the nozzle 5000 K, the Mach number at the traffic flow in the supersonic part of the nozzle reaches 2.5.Upon cooling, a mixture of U-F-Ar-He-H in the expanding area of the Laval nozzle is the condensation of a part of the elemental uranium and there is a two-phase stream containing a fine powder of uranium molecules of hydrogen fluoride, fluorine, fluorides of uranium atoms of argon and helium. The dilute stream outlet of the nozzle with hydrogen to reduce the probability of recombination of molecules of uranium fluorides. The temperature in the receiver products directly behind the nozzle is 600 K.Condensed powder containing uranium and fluoride uranium was extracted from two-phase flow in a cascade of cyclones. The output of the element uranium with the e is reduced to the primary recovery of uranium hexafluoride UF6before uranium TRIFLUORIDE UF3and subsequent disproportionation of fluoride according to the equation
UF3-> 3/4 UF4+ 1/4 U.A device for implementing the known method (Fig. 1) includes an electric torch 1, consisting of a face of the cathode 2 and the anode 3. The output end of the anode is made in the form of a Laval nozzle 5. In the wall of the anode entered the injector 4 for filing in the plasma of uranium hexafluoride at the outlet of the Laval nozzle drilled channel 6 for supplying hydrogen. For the Laval nozzle establish a cyclone and a filter for separating particulate and gas phases and the vacuum pump (Fig. 1).The known method and its instrumentation have drawbacks that hinder its industrial implementation:
output of elemental uranium is relatively low - less than 30% of theoretical; this means that it is necessary to extract the uranium from the total mass of the obtained product and create another production line to restore the remaining 70% of the uranium from the non-volatile fluorides of uranium contained in this weight;
- uranium mixed with other products recovery receive in the form of a pyrophoric powder prone to oxidation in air and even to spontaneous combustion, which is of great potential is a;
in processes of this type, especially when using quenching in supersonic nozzles, are formed of micron and submicron powders, which are virtually trapped cyclones.Task to be solved by the present invention is directed, is the complex processing of uranium hexafluoride, ending with obtaining uranium in a compact form, the full utilization of anhydrous hydrogen fluoride, safety improvement process. For task processing of uranium hexafluoride to uranium metal and anhydrous hydrogen fluoride proposed a method based on hydrogen recovery of uranium hexafluoride at high temperatures, carried out in one processing unit and consisting of four series-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 of uranium hexafluoride with hydrogen is converted into uranium-formotorola plasma containing a mixture of uranium atoms, hydrogen and fluorine, MoE 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. On the output (U-F-H)-plasma zone of the electric discharge occurs in the intensive recombination of molecules of uranium fluorides, followed by a powerful light radiation and condensation of non-volatile under normal conditions of fragments of molecules of uranium hexafluoride: tetrafluoride and uranium TRIFLUORIDE and elemental uranium. Recombination can lead to the formation of volatile fluorides: penaflorida and even uranium hexafluoride. Tempering reduces the depth and rate of recombination, but not radically changes the situation.It is most preferable to obtain the plasma in the flow of the mixture of uranium hexafluoride and hydrogen using electrodeless electric discharge (high-frequency induction, high-frequency capacitive, microwave). If there are no restrictions on the purity of the obtained uranium, for this purpose you can use the arc discharge by applying an electric arc plasma torches with the cathodes of lindanirvana or thoriated tungsten and the anodes of alloy copper magnetic twist is, is received by the reaction (1), but in this case, the potential of the first stage, the lower and main load restoration element uranium is transferred to the second stage.In the second stage of the reduction products of uranium hexafluoride transfer in the condensed phase, which is several orders of magnitude slower recombination processes, and the process of recovery of uranium continues to receive liquid uranium. This operation is as follows. Uranium-formotorola plasma obtained at the first stage, is directed to a bath of molten uranium tetrafluoride, and the second was obtained as follows. Download tetrafluoride uranium placed in a cooled cylindrical shell, transparent to radio frequency electromagnetic fields, resistant to the corrosive action of molten fluorides of uranium. The shell specified in the insert into the inductor high frequency generator coaxially with the discharge chamber, which receive 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 high-frequency voltage; zone melt tetrafluoride uranium interacts with a high-frequency field, making the whole download fast the/SUB> when interacting with (U-H-F)-plasma (or (U-F-H)-flame) involves condensation of uranium and lower fluorides of uranium; occurs simultaneously disproportionation of the latter in accordance with equations
< / BR>As the reactions 4-6 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 - 1133oC, density - 19,04 g/cm3; melting point of the uranium tetrafluoride - 1036oC, the density is to 6.43-of 6.95 g/cm3; the melting point of uranium TRIFLUORIDE - 1427oC, density of 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 is deposited metal and the emergence of fluoride in the surface layer is exposed to hydrogen plasma, and tetraploid uranium will float in the molten uranium TRIFLUORIDE.Thus, within a few minutes under the action of the plasma flow and direct high frequency heating is a full recovery of uranium from uranium hexafluoride and the initial load of uranium tetrafluoride. Decrease poslednego the ode, which evaporates from the zone of recovery of uranium.The third stage is carried out simultaneously with the first two, the removal of liquid uranium from the bottom of the reactor shell and filling it in a protective atmosphere in a cooled mold, the capacity of which is selected based on the accepted commercial standard for the form and weight of uranium billets.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 thereby ensuring 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.Device for processing gaseous uranium hexafluoride fundamentally SOS is ornago plasma; the concept of a plasma reactor is actually the plasma torch and the power source of the plasma torch generator; if necessary, the plasma reactor can be replaced flame reactor for the recovery of uranium hexafluoride, which is a mixture of uranium hexafluoride with hydrogen is heated pterodactyl flame (see equation 1);
- tight casing with a cover, through which the center inside the casing is mentioned gas-phase reactor; around the last in the cover concentrically located annular filtration module for separating gaseous and particulate products, collected from a multi-layer metal-ceramic elements, equipped with ejection regeneration;
- high-frequency metal reactor direct induction heating for melting of uranium fluorides, recovery and disposal of liquid elemental uranium in a cooled mold; the concept of high-frequency reactor is actually the reactor, i.e. the shell, where smelted uranium, and power supply - high frequency generator.Diagram of the device shown in Fig.2. Plasma reactor represents, depending on the type of generator 1 of the cooled tubular element 2, made or electric, or of corrosion-resistant metal that is stable in fluoride media at high temperatures. Plasma reactor equipped with adapter 4 for transmission of electromagnetic energy from the generator 1 (inductor, the external electrodes, the waveguide, the inner electrodes, etc.,) and injectors 3 to enter into the reactor of hydrogen and uranium hexafluoride. In oxy-fuel version of the gas-phase reactor is a longer tubular metal element with external cooling, made of corrosion-resistant Nickel alloy, but instead of a generator it is connected to the source of fluorine (balloons, electrolysis bath). In this case, the generator is above a source of fluorine, and the adapter valve for supplying fluorine.Mentioned plasma reactor is sealed inside the casing 5 through the cover 6 in the center of the latter; concentrically arranged around the plasma reactor are sintered multilayer elements 7 of the filtration module, equipped with nozzles 8 for pulse sectional ejection regeneration. The casing in the lower part is made in the form of a truncated cone 9, the bottom of which is hermetically connected with the above-mentioned high-frequency metallodielectric reactor.High-frequency metal reactor placed inside the inductor 14 a high-frequency generator 15. A reactor equipped with a bottom 16 and outlet 17 to output the final product of the processing - liquid elemental uranium. The diameter of metal-dielectric high-frequency reactor is slightly greater than the diameter of the plasma reactor. Tapered transition from the plasma reactor to high-frequency reactor provides ingress into the reactor plaque with metal elements 7 discharged from their surface during regeneration.Drain liquid uranium is made in the form of S-shaped pipe is uranium conversion in the last elemental uranium. Under the outlet pipe is water cooled, the mold 19.The above-described device operates as follows. To the plasma reactor 2 bring electric power from the generator 1, and then enter the flow of hydrogen through one of the injectors 3 and excite in him the electric discharge, resulting in a stream of hydrogen plasma. As generator 1 used in different variants of the high-frequency generator with tunable frequency in the range of 0.44-13.56 MHz microwave generator with a frequency of 2450 MHz, thyristor rectifier. In the case of using a fluorine-hydrogen flame generator is a source or reservoir of fluoride.Gaseous uranium hexafluoride is served through a different injector parallel from the container, heated to a temperature close to its melting temperature; at the entrance of the plasma reactor causes dissociation of uranium hexafluoride and the formation of uranium-formotorola plasma.The flow of uranium-formotorola plasma comes in contact with the loading of uranium tetrafluoride UF4placed beforehand in a water-cooled metal-dielectric high-frequency reactor 10, in the inductor 14 Vysocanska conductivity of this load increases and through the slits 11 are induced induction currents, warming up in a few minutes the entire volume of the above-mentioned load, the loading of uranium tetrafluoride is melted.On the surface of the melt condensation occurs uranium and lower fluorides of uranium from uranium-formotorola plasma, and the disproportionation of the latter and further recovery of uranium. The surface layer is enriched uranium, which being much heavier than uranium fluorides settles down, and fluorides pop up. The temperature inside the load exceeds the melting point of uranium TRIFLUORIDE (1427oC) and is 1450-1600oC.After 5-15 minutes after the start of the process the entire load in the high-frequency metal reactor consists of molten uranium, the level of the melt is increased due to the receipt of uranium from uranium-formotorola plasma, it is necessary to drain the uranium through the drain hole 17 in the bottom 16 or start extraction of the ingot.One of the options draining liquid uranium, shown in Fig.2 and automatically providing pure uranium without a mixture of fluorine - discharge through the S-shaped pipe 18, the upper point of which is at the level of the upper coil of the inductor 14. Liquid uranium output in a cooled mold 19.During operation of the plasma reactor and the high-frequency metal reactor turns the gas phase: hydrogen fluoride HF, as well as some amount of excess hydrogen. After the interaction of the uranium-formotorola plasma with the surface of the melt gases fill the sealed casing 5 and out through the filtration module 7 in the pipe connected to the condenser and transport container for collecting liquid hydrogen fluoride. When hydrogen fluoride is separated from the hydrogen, the latter sent forth for recycling.In the process of removing hydrogen fluoride from the housing 5 through the filtration module on the outer surface of the multilayer filter elements are deposited aerosols, the size of which is 0.1-0.01 µm. For the regeneration of these elements use the pulse sectional ejection regeneration, in which the main regenerating gas is already filtered gas. Regeneration sections of the filtration module produces alternately, without stopping filter by short-term, within 0.1 to 0.3 with compressed nitrogen through each nozzle. The nitrogen consumption for regeneration does not exceed 0.05% of the volume of the filtered gas. Design of multilayer filtrowa microns.The method and the device tested in the laboratory using different modes and sources of high temperatures.Example 1.To obtain (U-H-F)-plasma used high-frequency induction discharge. Plasma reactor made of cut copper pipe with internal cooling and longitudinal sections, tightly filled with dielectric inserts magnesium oxide; the reactor is placed in the inductor of the high-frequency generator with a frequency of 13.56 MHz, the internal diameter of the reactor is 0.05 m, the length of 0.25 m of the Oscillating power generator 30 kW.The reactor direct induction heating is performed in the same manner as the plasma rector, but fed from the second high-frequency generator with a frequency of 1.56 MHz. The oscillating power generator 30 kW. The external diameter of the cylindrical part of the reactor 0.15 m, an internal diameter of 0.11 m Top diameter of the conical part - 0,25 m the Bottom of the rector made in the form of a disk of silicon carbide, in the annular gap which is fixed the reactor vessel. In the center of the specified disk is a hole made hermetically closed tube of silicon carbide.Hydrogen fluoride were taken through a sintered filter; the TCI.The flow of uranium hexafluoride was 4.2 kg U/h, the initial load tetrafluoride uranium - 7.5 kg U.High-frequency plasma torch originally only worked on hydrogen at a flow rate for the last 1.6 nm3/h to melt the top layer of the load UF4. Through 1.6 minutes of operation torch the top layer of the boot is melted and was the second high frequency generator supplying metal reactor direct induction heating. Download the inductor is saturated with melt UF4immediately start to heat induction currents and through 7,3 min after switching high-frequency oscillations of the melt that was fixed by changing the boot mode of the generator and the lowering of the melt tetrafluoride uranium metal reactor.At the same time in the melting tetrafluoride included the supply of uranium hexafluoride. In the upper part of the high-frequency metal reactor, there is an accumulation of molten uranium due to uranium, condensing directly from plasma and occurs when the disproportionation of uranium fluorides in equations 4-6. As it melts, download molten uranium sank to the bottom of the reactor.Chere is C the bottom of the high-frequency metal reactor direct induction heating. From the reactor flowed melt and fill the mold.The total duration of work install 1 hour 12 minutes processed by calculation 3,92 kg U from uranium hexafluoride. From moulds pulled ingot weighing 10,3 kg, after cooling and disassembly of metal-dielectric reactor and revision filter was removed 0,63 kg number of residues, mainly the remains of a crust of slag, caught in the wall of the reactor.Theoretical yield is of 10.72 kg U; achieved output of uranium 96,1%. In the condenser gathered 4.3 kg HF.Example 2.To obtain (U-H-F)-plasma used microwave discharge. Plasma reactor made of cut quartz tube, equipped with an external air cooling. The power source is a microwave generator "Violet" with two magnetrons and two waveguides; generator frequency is 2450 MHz, the diameter of the reactor is 0.05 m, the length of 0.18 m Oscillating power generator 5 kW.High-frequency metal reactor direct induction heating is performed as described in example 1, with the same power supply source and with the same arguments.Hydrogen fluoride were taken through a sintered filter; for Metallica the The flow of uranium hexafluoride was 3.7 kg U/h, the initial load tetrafluoride uranium - 8.2 kg U.Microwave plasmatron originally only worked on hydrogen at a flow rate of the last 1.8 nm3/h to melt the top layer of the load UF4. Through 1.6 minutes of operation torch the top layer of the boot is melted and was included high frequency generator supplying metal reactor direct induction nagra. Download the inductor is saturated with melt UF4immediately start to heat induction currents and through 7,1 min after switching high-frequency oscillations melted.Simultaneously with the melting tetrafluoride included the supply of uranium hexafluoride. Through 58 min turned off the flow of uranium hexafluoride, both the frequency generator and remotely removed the stopper from the bottom of the metal reactor direct induction heating. From the reactor flowed melt and fill the mold.The total duration of work install 1 h 07 min processed by calculation 3,02 kg U from uranium hexafluoride. From moulds pulled ingot weighing 10.7 kg, after cooling and disassembly of metal-dielectric reactor and revision filter was removed 0,87 cstore gathered 4.05 kg HF.Example 3.To obtain (U-H-F)-plasma used electric arc discharge at a constant current. The power source of the plasma torch - controlled rectifier with automatic regulation of the current. Plasma reactor is a continuation of the anode arc plasmatron DC and made of cut onelevel pipe, equipped with external cooling. The inner diameter of the reactor - 0.03 m, the length of 0.18 m the Power of the plasma torch 25 kW.High-frequency metal reactor direct induction heating is the same as in examples 1, 2; line removal and collection of hydrogen fluoride is made the same way.The flow of uranium hexafluoride was 4.8 kg U/h, the initial load tetrafluoride uranium - 8,5 kg U.An electric torch originally only worked on hydrogen at a flow rate of 7 nm3/h to melt the top layer of the load UF4. Through 1,2 min of operation torch the top layer of the boot is melted and was included high frequency generator supplying metal reactor direct induction heating. Download the inductor is saturated with melt UF4immediately start to heat induction current is of aflorida included the supply of uranium hexafluoride.After 55 minutes and turned off the flow of uranium hexafluoride, both generator and remotely removed the stopper from the bottom of the metal reactor direct induction heating. From the reactor flowed melt and fill the mold.The total duration of work install 1 hour 11 minutes processed by calculation of 4.4 kg U from uranium hexafluoride. From moulds pulled ingot 11,9 kg, after cooling and disassembly of metal-dielectric reactor and revision filter was removed 1,43 kg of various residues. Theoretical output is 12,9 kg U; achieved output of uranium 92,2%. In the condenser gathered 4.5 kg HF.Example 4.For the primary recovery of uranium hexafluoride used flame reactor using fluorine-hydrogen flame. The parameters of the flame reactor: flow of uranium hexafluoride - 4,53 kg U/h, consumption of fluoride 0.05 kg/kg UF6the amount of hydrogen - 107% of the stoichiometry of the reaction UF6+ H2-> UF4+ 2HF.High-frequency metal reactor direct induction heating is the same as in examples 1 and 2. The oscillating power generator 60 kW, frequency of 2.2 MHz, bootstrapping tetrafluoride uranium - 9.1 kg U. Line removal and collection of fluoride motorolamotorola flame at the rate of the last 0.96 nm3/h to melt the top layer of the load UF4. Through 4,2 min processing the upper layer of the boot is melted and was included high frequency generator supplying metal reactor direct induction heating. Download in the inductor after 4 min after switching high-frequency oscillations, melted. Simultaneously with the melting tetrafluoride included the supply of uranium hexafluoride.After 1 h 17 min turned off the flow of uranium hexafluoride, fluorine and hydrogen, high frequency generator and remotely removed the stopper from the bottom of the reactor direct induction heating. From the reactor flowed melt and fill the mold.The total duration of work install 1 h 32 min processed by calculation 5.7 kg U from uranium hexafluoride. From moulds pulled ingot total weight of 12.9 kg, after cooling and disassembly of metal-dielectric reactor and revision filter was removed 2.1kg different residues.Theoretical yield is of 14.76 kg U; achieved the release of uranium is 87.4%. In the condenser gathered 5,1 kg HF. 1. The method of conversion of uranium hexafluoride to uranium metal and anhydrous hydrogen fluoride by hydrogen recovery of uranium hexafluoride at high especiauy complete decomposition of uranium hexafluoride to elemental uranium and/or its lower fluorides, the obtained high temperature uranium-fluorine-hydrogen stream is directed to the surface of the boot tetrafluoride uranium melt the surface of the specified load and at the same time lead volumetric high-frequency induction heating of a specified load to full recovery of uranium from loading and uranium from uranium hexafluoride, and then remove the accumulated molten uranium through the bottom of the high-temperature membrane surrounding the initial tetrafluoride uranium, and continuously divert anhydrous hydrogen fluoride from the zone of recovery of uranium through the filtration module.2. The method according to p. 1, characterized in that the heating of a mixture of uranium hexafluoride with hydrogen and obtaining high temperature uranium-fluoride-hydrogen stream are in the high-frequency induction discharge and the surface of the primary boot tetrafluoride uranium is heated by the flow of high-frequency induction plasma.3. The method according to p. 1, characterized in that the heating of a mixture of uranium hexafluoride with hydrogen and obtaining high temperature uranium-fluoride-hydrogen stream are in the high-frequency capacitive discharge and the surface of the primary boot tetrafluoride uranium heat flow HF eat and getting high-temperature uranium-fluorine-hydrogen stream lead in a microwave discharge and the surface of the primary boot tetrafluoride uranium is heated by the flow of microwave plasma.5. The method according to p. 1, characterized in that the heating of a mixture of uranium hexafluoride with hydrogen and obtaining high temperature uranium-fluoride-hydrogen stream are in the arc discharge and the surface of the primary boot tetrafluoride uranium is heated by the flow of electric arc plasma.6. The method according to p. 1, characterized in that the recovery of uranium hexafluoride to the lower fluorides of uranium and obtaining uranium-fluorine-hydrogen stream are in the fluorine-hydrogen flame and the surface of the primary boot tetrafluoride uranium is heated by the flow of the fluorine-hydrogen flame.7. Device for the processing of uranium hexafluoride to uranium metal and anhydrous hydrogen fluoride, comprising a reactor for recovery of uranium from uranium hexafluoride and capture of elemental uranium and anhydrous hydrogen fluoride, wherein the reactor for recovery of uranium from uranium hexafluoride consists of a gas-phase reactor, paired with a generator of high temperatures, for translation of a mixture of uranium hexafluoride and hydrogen in uranium-fluorine-hydrogen plasma or a high-temperature chemical flame with adapter for interoperability generator with gas-phase reactor and injectors Dora direct induction heating of the initial loading of uranium tetrafluoride and uranium, coming from gas-phase reactor, made of tube segment of a nonmagnetic metal having internal cooling and longitudinal sections, tightly filled with inserts made of heat-resistant material having dielectric properties located downstream gas-phase reactor and coaxially with it, powered by a high-frequency generator, inductively associated with the load, the pressure-tight casing with lid, connecting the gas-phase reactor with a high-frequency metal reactor piping for drainage of liquid uranium in a cooled mold, made in the S-shaped, with one end of the said pipeline starts at the bottom center of the high-frequency reactor, the other end of the pipeline is above the mold, top Syao tocha pipeline is not below the upper coil of the inductor, covering high frequency metal reactor, metal-ceramic filtration module located in the lid of the mentioned casing around the gas-phase reactor coaxially with the latter and provided with ejection recovery system, piping for drainage of anhydrous hydrogen fluoride.8. The device according to p. 7, characterized in that as genetor made in the form of a cooled tubular element, made from the composition of the non-magnetic metal/insulator.9 the Device according to p. 7, characterized in that as the generator of the high temperature use of the radio frequency generator, adapter are external electrodes, gas-phase reactor is made in the form of a tubular element of heat-resistant material, preserving the dielectric properties at high temperatures.10. The device according to p. 7, characterized in that, as a generator of high temperatures using microwave generator, a waveguide adapter is, gas-phase reactor is made in the form of a tubular element of heat-resistant material, preserving the dielectric properties at high temperatures.11. The device according to p. 7 characterized in that, as a generator of high temperatures using microwave generator, a waveguide adapter is, and gas-phase reactor combined with a circular metallic waveguide is referred to as the microwave generator.12. The device according to p. 7, characterized in that as the generator of the high temperatures used electric arc generator DC adapter is internal electrodes, and gas-phase reactor is made as prodau, corrosion resistant in an atmosphere of fluorine and fluorides.13. The device according to p. 7, characterized in that as the generator of the high temperatures used fluorine-hydrogen flame, and the gas-phase reactor made of cut metal pipes of corrosion-resistant Nickel alloy.14. The device according to p. 7, characterized in that the high-frequency metal reactor equipped with internal cooling, and the cooling channels are in the body of the reactor between the said longitudinal slits, and the insertion of a dielectric material is cooled through contact with the metal walls in the above sections.15. The device according to p. 7, characterized in that the diameter of the high-frequency metal reactor is larger than the diameter of gas-phase reactor, the transition between the reactor has the shape of a truncated cone.16. The device according to p. 7, characterized in that the pipeline for removal of liquid uranium is made in the form of a device for pulling the ingot uranium.17. The device according to p. 7, characterized in that the metal-ceramic filtration module made of multilayer metal-ceramic elements, equipped with nozzles for ejecti the
FIELD: processes for making powders of molybdenum, tungsten and rhenium by reduction of ammonium salts for further using them for producing hexafluorides of respective metals and in gas-fluoride technique.
SUBSTANCE: method is realized by reducing ammonium salts of refractory metals by hydrogen. Method comprises steps of reducing ammonium salts at temperature 350 - 550 C while using hydrogen of hydrogen-containing gas generated in cathode space of electrolyzer for producing fluorine and containing, vol. %: hydrogen, 92 - 94; hydrogen fluoride 5 - 6; inert impurities, the balance.
EFFECT: simplified lowered-cost manufacturing process.
1 dwg, 1 tbl, 3 ex
FIELD: non-iron industry.
SUBSTANCE: invention relates to method for reducing of manganese oxide from ore to manganese carbide. Solid metal oxide is brought into contact with gaseous reducing and cementation agent (e.g., hydrogen-hydrocarbon mixture), and optionally, with inert gas at temperature of 1000-12500C.
EFFECT: environmentally friendly method; decreased energy consumption.
21 cl, 22 dwg, 1 tbl
FIELD: spraying targets and methods of manufacture of such targets.
SUBSTANCE: proposed method includes making the blanket of metal to be sprayed which contains tantalum, niobium or their alloy, performing cold cross rolling of blank and cold treatment of rolled blank for obtaining shaped blank. Proposed target is made by above method; it contains at least one rectifying metal. Target is designed for magnetron with hollow cathode and is characterized by the following parameters: (a) size of grain acc. to ASTM 5 or finer; (b) combined texture (111)-(100); (c) homogeneous size of grains varying within ±2 acc. to ASTM or their combination. Assembly of spraying target includes target proper and upper part made from non-sprayable material and secured to side walls of target and/or outer envelope made from non-sprayable material and secured to target. Proposed method of extraction of rectifying metal from used target assembly includes hydrogenation of rectifying metal.
EFFECT: smooth destruction of target and smooth precipitation of material on substrate.
57 cl, 5 dwg, 2 tbl, 1 ex
SUBSTANCE: proposed method includes reduction of silver chloride at heating and holding at heat in flow of gaseous hydrogen, bubbling of gas escaping from reaction chamber through water and obtaining aqueous solution HCl. Reduction is performed from silver chloride formed at refining of noble metals and ground to size of ≤100 mcm and located in reaction chamber at thickness of layer of ≤20 mm at temperature of 450°C±5°C by gaseous hydrogen heated to holding temperature.
EFFECT: increased degree of extraction of silver from silver chlorides.
1 tbl, 1 ex
SUBSTANCE: invention refers to metallurgy and can be used for fabricating of metallurgical briquettes which are effective substitutes of coke in blast and cupola iron production. The mixture is prepared which includes 94-98 mas.% of filling compound - a carbon containing material, and the rest is a binding material such as an activated aluminium- boron- phosphate concentrate. Then forming of mixture is performed in an accessory under pressure and vibration. Activation of the aluminium- boron- phosphate concentrate is performed before immediate preparation of mixture by means of the binding material treatment with nano second electromagnetic impulses of 0.5-0.8 MW power.
EFFECT: invention upgrades quality of metallurgical briquettes due to their increased strength characteristics at a minimal quantity of a binding material and at a considerable reduction of time for briquette fabrication owing to briquettes self hardening and avoiding thermal treatment.
2 tbl, 2 ex
SUBSTANCE: processed material in form of cobalt powder is put into reactor made out of refractory material and heated to temperature 700-750°C; further de-hydrated hydrogen is run through reactor at rate of supply 300 ml/min during 60 min for heterogenic reduction of cobalt chloride to powder of metallic cobalt. Reduced powder of metallic cobalt is heated to temperature 600-650°C in the same reactor; flow of chlorine is run through the reactor at rate of supply 100 ml/min during 30 min for partial chlorination of metal cobalt with preferential formation of chlorides of volatile impurities. Powder of metallic cobalt undergone partial chlorination is pressed into a rod and is subject to electronic vacuum zone re-crystallisation for production of crystals of high pure cobalt. Produced crystals are subject to electronic re-melting in the crystalliser cooled from both sides to whole depth not less, than two times till obtaining a flat ingot with structure of high quality.
EFFECT: great increase of purity of cobalt designed for fine film metallisation by magnetron sputtering of targets as cobalt purity substantially determines electro-physical parametres of applied thin layers.
1 dwg, 1 tbl, 1 ex
FIELD: process engineering.
SUBSTANCE: invention relates to metallurgy. Proposed method comprises zone chlorination of nickel metal in gaseous chlorine flow at 940 to 970°C to produce nickel chloride powder. Then, one-stage sublimation of nickel chlorides powder in atmosphere of humid argon at 940 to 970°C is carried out to produce nickel chloride vapors. After sublimation, homogeneous recovery of nickel chloride vapors is performed in dehydrated hydrogen flow at 950 to 980°C and hydrogen-to-argon-flow rate ratio of 1:2-1:3 to produce foil and recovered nickel crystals. Now, said foil and crystals are pressed and vacuum zone re-crystallization is effected to produce ingots. The latter are remelted in cooled flat crystalliser in vacuum to produce flat ingot to be remelted on both sides for complete depth, at least, two times. Invention covers also device to produce nickel chloride powder for dispersed targets and device for sublimation and homogeneous recovery of nickel chloride.
EFFECT: sharp increase in nickel purity.
4 cl, 2 dwg, 1 tbl, 1 ex
FIELD: process engineering.
SUBSTANCE: invention relates to metallurgy. Proposed method comprises zone chlorination of nickel metal in gaseous chlorine flow at 940 to 970°C to produce nickel chloride powder. Then, one-stage sublimation of nickel chlorides powder in atmosphere of humid argon at 940 to 970°C is carried out to produce nickel chloride vapors and diffusion recovery of nickel chloride vapors in dehydrated hydrogen at 950 to 980°C to produced compact recovered nickel. Now, said foil and crystals are pressed and vacuum zone re-crystallization is effected to produce ingots. The latter are remelted in cooled flat crystalliser in vacuum to produce flat ingot to be remelted on both sides for complete depth, at least, two times. Invention covers also device to produce nickel chloride powder for dispersed targets and device for sublimation and homogeneous recovery of nickel chloride.
EFFECT: sharp increase in nickel purity.
3 cl, 2 dwg, 1 tbl, 1 ex
SUBSTANCE: method includes homogeneous reduction of its volatile compounds by hydrogen in reactor made of refractory material at feeding with transportation by argon of volatile compound of reduced metal and hydrogen feeding into reduction zone. Reduction is implemented in reactor, consisting of evaporation zone and reduction zone, by means of feeding after evaporation from of volatile compound of metal into reduction zone. At usage in the capacity of compounds of halogenide metals or metal oxides into reduction zone it is fed correspondingly halogen-hydrogen or water vapors, at ratio of feed rates of hydrogen and argon 1:2 with receiving of metal in the form of metal foil, precipitated on heated walls of reactor. Device includes reactor, implemented of refractory material - fused quartz, treated material in the form of compound if the received metal, heater and feed system of gas. Reactor is implemented with quartz diaphragm for separation into evaporation zone and reduction zone, heated up to temperature 850-950°C separately by means of heaters.
EFFECT: increasing of metals grade at reduction of halogenides and oxides of metals.
2 cl, 1 dwg, 1 tbl, 3 ex
SUBSTANCE: invention refers to procedure for metal production. The procedure consists in reduction of metal oxides with hydrogen at presence of calcium hydride in heated closed reactor. Also stoichiometric amounts of reduced metal oxide and calcium hydride are spaced in the reactor at 15-20 cm one from another. The reactor is filled with hydrogen to pressure 0.1-0.3 at and metal oxide is heated at temperature 200-1000 °C, while calcium hydride at 80-120°C to complete reduction of oxide.
EFFECT: production of required amount of metals at minimal consumption of hydrogen.
3 ex, 1 dwg
FIELD: rare, dispersed and radioactive metal metallurgy, in particular hydrometallurgy.
SUBSTANCE: invention relates to method for reprocessing of polymetal, multicomponent, thorium-containing radwastes, formed when reprocessing of various mineral, containing rare-earth elements, Nb, Ta, To, V, Zr, Hf, W, U, etc. Method includes treatment of solution and/or slurry with alkaline agent; introducing of sulfate-containing inorganic compound solution and barium chloride; treatment of obtained hydrate-sulfate slurry with iron chloride-containing solution, and separation of radioactive precipitate from solution by filtration. As alkali agent magnesia milk containing 50-200 g/dm2 of MgO is used; treatment is carried out up to pH 8-10; sodium sulfate in amount of 6-9 g Na2SO4/dm2 is introduced as solution of sulfate-containing inorganic compound; barium chloride solution is introduced in slurry in amount of 1.5-3 g BaCl2/dm2. Hydrate-sulfate slurry is treated with solution and/or slurry containing 0.8-16 Fe3+/dm2 (as referred to startingsolution) of iron chloride, followed by treatment with high molecular flocculating agent and holding without agitation for 0.5-2 h. Radioactive precipitate is separated from mother liquor, washed with water in volume ratio of 0.5-2:1; then washed with sodium chloride-containing solution and/or slurry in volume ratio of 0.5-2:1; radioactive precipitate is removed from filter and mixed with mineral oxides in amount of 0.5-0.8 kg MgO to 1 kg of precipitate. Formed pasty composition is fed in forms and/or lingots and presses with simultaneous heating up to 80-1200C.
EFFECT: filtrate with reduced radioactivity due to increased codeposition coefficient of natural Th-232-group radioactive nuclide, in particular Ra-224 and Ra-228, with radioactive precipitates.
10 cl, 1 ex
FIELD: chemical technology; recovery of deactivated and decontaminated radioactive industrial wastes.
SUBSTANCE: proposed method that can be used for deactivating and decontaminating industrial radioactive wastes incorporating Tb-232 and their daughter decay products (Ra-228, Ra-224), as well as rare-earth elements, Fe, Cr, Mn, Sl, Ti, Zr, Nb, Ta, Ca, Mg, Na, K, and the like includes dissolution of wastes, treatment of solutions or pulps with barium chloride, sulfuric acid, and lime milk, and separation of sediment from solution. Lime milk treatment is conducted to pH = 9 - 10 in the amount of 120-150% of total content of metal oxyhydrates stoichiometrically required for precipitation, pulp is filtered, and barium chloride in the amount of 0.4 - 1.8 kg of BaCl2 per 1 kg of CaCl2 contained in source solution or in pulp, as well as pre-diluted sulfuric acid spent 5 - 20 times in chlorine compressors in the amount of 0.5 - 2.5 kg of H2SO4 per 1 kg of BaCl2 are introduced in filtrate. Alternately introduced in sulfate pulp formed in the process are lime milk to pH = 11 - 12, then acid chloride wash effluents from equipment and industrial flats at pulp-to-effluents ratio of 1 : (2 - 3) to pH = 6.5 - 8.5, and pulp obtained is filtered. Decontaminated solution is discharged to sewerage system and sediment of barium and calcium sulfates and iron oxysulfate are mixed up with oxyhydrate sediment formed in source pulp neutralization process; then 35 - 45 mass percent of inert filler, 10 - 20 mass percent of magnesium oxide, and 15 -m 25 mass percent of magnesium chloride are introduced in pasty mixture formed in the process while continuously stirring ingredients. Compound obtained is subjected to heat treatment at temperature of 80 - 120 oC and compressed by applying pressure of 60 to 80 at.
EFFECT: reduced radioactivity of filtrates upon separation of radioactive cakes due to enhanced coprecipitation of natural radionuclides.
7 c, 1 ex
FIELD: chemical technology; deactivation and decontamination of radioactive industrial products and/or wastes.
SUBSTANCE: proposed method designed for deactivation and decontamination of radioactive industrial products and/or production wastes incorporating Th-232 and its daughter decay products (Ra-228, Ra-224), as well as rare-earth elements, Fe, Cr, Mn, Al, Ti, Zr, Nb, Ta, Ca, Mg, Na, K, and the like and that ensures high degree of coprecipitation of natural radionuclides of filtrates, confining of radioactive metals, and their conversion to environmentally safe form (non-dusting water-insoluble solid state) includes dissolution of wastes, their treatment with barium chloride, sulfuric acid, and lime milk, and separation of sediment from solution. Lime milk treatment is conducted to pH = 9-10 in the amount of 120-150% of that stoichiometrically required for precipitation of total content of metal oxyhydrate; then pulp is filtered and barium chloride is injected in filtrate in the amount of 0.4 - 1.8 kg of BaCl2 per 1 kg of CaCl2 contained in source solution or in pulp and pre-dissolved in sulfuric acid of chlorine compressors spent 5-20 times in the amount of 0.5 - 2.5 kg of H2SO4 per 1 kg of BaCl2. Then lime milk is added up to pH = 11 - 12 and acid chloride wash effluents of equipment and production floors are alternately introduced in sulfate pulp formed in the process at pulp-to-effluents ratio of 1 : (2-3) to pH = 6.5 - 8.5. Filtrate pulp produced in this way is filtered, decontaminated solution is discharged to sewerage system, sediment of barium and calcium sulfates and iron oxysulfate are mixed up with oxyhydrate sediment formed in source pulp neutralization, inert filler and 0.5 - 2 parts by weight of calcium sulfate are introduced in pasty mixture while continuously stirring them. Compound obtained in the process is placed in molds, held therein at temperature of 20 - 50 oC for 12 - 36 h, and compacted in blocks whose surfaces are treated with water-repelling material.
EFFECT: reduced radioactivity of filtrates upon separation of radioactive cakes.
8 cl, 1 dwg, 1 ex