RU2164716C1 - Method and device for solidifying liquid radioactive wastes - Google Patents

Abstract

FIELD: disposal of liquid radioactive wastes. SUBSTANCE: method involves primary treatment of wastes, their concentration and mixing up with fluxing additives, heating of mixture obtained, its melting, melt draining to tanks, and production of blocks. Concentration is effected by spray drying and calcination at 600-800 C. Used as fluxing additives are mineral- forming compounds taken in amount sufficient to obtain blocks in the form of mineral-like material of following group of minerals: aegirite, jadeite, aegirite-augite, arfvedsonite, orthite, schorlite, lovchorrite, andradite, or their mixtures. Fusion of this material is effected by its melting at 1250-1800 C with melt exposed to induction field. Device implementing proposed method (Fig. 1) has tank 1 holding liquid radioactive wastes, concentration apparatus 3, induction melter 16 incorporating water-cooled drain unit 19, tank 12 holding fluxing additives that incorporates dosing apparatus 13, mixer 11, exhaust gas decontaminating unit 9, pipelines, and valves. In addition, device is provided with high-temperature heat-insulated filter 8 and pipeline interconnecting concentration apparatus 3, mixer 11, and filter 8. Concentration apparatus is made in the form of externally heated cylindrical vessel mounted above melter; its top lid mounts spray nozzle 5 communicating with liquid-waste tank 1 and with compressed air source 2. Induction melter is made in the form of water-cooled crucible 16 whose side walls are transparent to variable electromagnetic field and whose bottom accommodates melting chamber 15 and drain chamber 17 intercommunicating in lower part of crucible. Melting chamber communicates through mixer 11 with concentration apparatus 3, filter 8, and flux dosing apparatus 13. EFFECT: improved safety of solidifying process and environmental friendliness in long-time storage of radioactive wastes. 7 cl, 2 dwg, 5 tbl

Description

 The invention relates to the field of environmental protection, and in particular to the technology of solidification of liquid radioactive waste that is generated during the regeneration of spent nuclear fuel, decontamination, as well as during other radiochemical and metallurgical processes.

 In the field of ensuring human life in an ecologically safe environment, an important place is occupied by the problem of the neutralization of various liquid radioactive waste (hereinafter - LRW) generated in the process of processing nuclear fuel. One of the main tasks is a significant reduction in volumes (concentration) of LRW, as well as their transfer to a solid state, i.e. in a form convenient for transportation and reliable long-term storage for 500 - 1000 years. Thus, in the processing of irradiated nuclear fuel, LRW is formed containing components of various technological solutions and corrosion products of technological devices containing fission fragment radionuclides, nuclear fuel residues and transuranic elements. Currently, the bulk of LRW is accumulated and stored in special storage tanks and only a small part of LRW is vitrified. The storage of radioactive waste without reprocessing does not meet modern environmental safety requirements and is a possible source of technogenic radiation accidents. The transfer of LRW into compact solid forms, convenient for transportation, storage and disposal, will significantly reduce this risk.

A known method of curing LRW of high and medium levels of activity, including their evaporation to 40-80% of residual moisture, mixing with a clay substance containing cement, molding a mixture, drying granules at 150 ^o C, calcination at 800 ^o C and firing at 1400 ^o C within 10-20 hours to obtain a ceramic type substance (German Patent No. 2726087, class B 03 B 9/06, 1978). The known method does not allow to obtain highly radioactive waste (hereinafter - HLW) in a sufficiently chemically stable and mechanically strong matrix.

 A known method of curing LRW, including evaporation, spray drying, calcining the obtained powder in a furnace before decomposition of nitric acid, and vitrification of HLW in the melting chamber of an induction furnace (Application of Japan 60-24440, CL G 21 F 9/16, publ. 06.12.1985 ) This method is the closest to the claimed and selected as a prototype.

 The installation for implementing this method consists of a combined LRW collection unit, a supply tank, an evaporation apparatus, a spray drying apparatus, annealing and melting chambers.

The disadvantage of this method is the difficulty of obtaining a temperature in the melter above 1200 ^o C, which does not allow to synthesize mineral-like materials of the required quality. This is due to the fact that heat is transferred to the melting zone from the melter wall heated by induction currents, which does not withstand high temperatures due to direct contact of the melt with the melter walls and their rapid corrosion. The known method is not suitable for the processing of sludge due to the use of evaporators of the shell type.

 A device for the vitrification of radioactive waste containing ion-exchange resins, including a container for LRW, a capacity of a dewatering apparatus, a dehydration apparatus connected to a separator and a condenser, a mixer tank connected to a dehydration apparatus, a container with glass former and a LRW tank (RF Patent 2115182, class G 21 F 9/16, published 09.09.1997). The mixer tank is connected to a storage tank, which is connected through an eddy apparatus to an induction furnace to produce a vitrified mass. The induction furnace contains a cold crucible with a movable inductor. The drain device consists of a drain pipe with a water-cooled jacket, a top cover and a water-cooled drain valve. At the same time, a water-cooled shirt of the drain pipe is built into the body of the cold crucible. The outlet of the furnace is connected in series with the exhaust gas filtration system, the condenser of the filtration system, the capacity of the filtration system, an absorption unit, a heater, a catalytic reactor and a condenser of a catalytic reactor.

 A disadvantage of the known device is that it is intended for solidification of medium and low activity wastes and cannot be used for HLW treatment, since most of the devices (LRW tank, dehydration device capacity, dehydration device, heterogeneous LRW tank, heterogeneous LRW dispenser, capacity - drive, feeder) are equipped with electric motors that are quickly destroyed in the radiation fields created by HLW. The known device does not provide the ability to remotely replace this equipment. In addition, the disadvantages of the known device are the high residual moisture content of the resulting concentrate and the frequency of the concentration operation, which reduces the productivity of the device.

 The closest in technical essence to the claimed device is a device for vitrification of LRW, including a container of homogeneous LRW, a container of additives for calcination, a container-mixer equipped with a dispenser, a dewatering apparatus (rotary calciner), a container-dust collector, a container with a glass former, a lock dispenser for glass-forming, a metal crucible with a fixed inductor, having a bottom drain pipe, equipped with a cooling jacket and its own inductor, as well as an exhaust gas neutralization unit c, including a dedusting device, a filter system condenser, a filter system capacitor capacity and gas purification (A. S. Nikiforov, V. V. Kulichenko, M. I. Zhikharev, Disposal of liquid radioactive waste. - M.: Energoatomizdat, 1985, p. . 85, 93, 94).

The disadvantages of the known device are the increased danger of radioactive contamination due to the complexity and insufficient reliability of the equipment operating in conditions of intense radiation, as well as the use of a melter with heating the melt from its wall, which (due to direct contact with the melt) corrodes quickly. In addition, the device has low productivity due to the return of condensate from the gas purification system to the tanks of the initial solution for recycling, and is also unsuitable for fixing HLW in the form of mineral-like blocks requiring temperatures above 1250 ^o C. for synthesis.

 The technical task of the invention is to create a technology for the curing of LRW of various compositions, suitable for remote and safe manufacture of mineral-like blocks, ensuring environmentally safe storage of radioactive substances for a long time.

This problem is solved in that in the claimed method of solidification of liquid radioactive waste (including their preparation, concentration and mixing with fluxing additives, heating the resulting mixture, melting, draining the melt into containers, cooling the melt and forming blocks), the concentration is carried out by spray drying and calcination at a temperature 600-800 ^o C, as fluxing additives, mineral-forming compounds are used in quantities that allow to obtain blocks in the form of a mineral-like material selected from gr minerals: Egirin, Jadeite, Egirin-augit, Arfvedsonite, Ortit, Sherlit, Lovchorrit, Andradit or their mixtures, and the synthesis of this material is carried out by melting at a temperature of 1250-1800 ^o C and with the direct influence of the induction field on the melt.

In particular, the technical problem is solved by the fact that when implementing the method for curing liquid radioactive waste enriched with alkaline elements and aluminum, Egirin, Jadeite, Egirin-augit, Arfvedsonite, Ortit, Sherlit or mixtures thereof are used as mineral-like material, and the material is synthesized at a temperature of 1300-1800 ^o C.

In particular, the technical problem is solved in that when implementing the method for curing liquid radioactive waste enriched with fission products and corrosion products of equipment, Lovchorrit and Andradit are used as mineral-like material, and the material is synthesized at a temperature of 1250-1500 ^o C.

 The problem is solved in that in the device for solidification of liquid radioactive waste (including a container for liquid radioactive waste, a concentration apparatus, an induction melter having a water-cooled drain device, a tank with fluxing additives, a metering unit, a mixer, an exhaust gas purification unit, a piping system and fittings) the device is additionally equipped with a high-temperature heat-insulated filter and a pipe connecting the concentration apparatus, mixer and the filter, the concentration apparatus is made in the form of a cylindrical vessel heated externally and located above the melter, in the upper cover of which there is an nozzle connected to a liquid radioactive waste tank and a compressed air source, the induction melter is made in the form of a water-cooled crucible with side walls transparent to an alternating electromagnetic field and bottom, inside the crucible, melting and drain chambers communicating with each other in the lower part of the crucible are formed, the melting chamber through a mixer with bschena with concentrating apparatus, filter and dispenser flux, the drain chamber is provided with water-cooled discharge device.

 In particular, the technical problem is solved in that each of the main components of the device — a container for liquid radioactive waste, a concentration apparatus with a filter, an induction melter, a container with fluxing additives, equipped with a dispenser, a mixer, an exhaust gas purification unit, are made in the form of remotely disassembled and replaceable modules.

 In particular, the technical problem is solved by the fact that when implementing the device, the side walls and the bottom of the body of the water-cooled crucible consist of a two-layer set of parallel water-cooled tubes assembled on a single collector lid and sealed with dielectric ceramics.

 In particular, the technical problem is solved in that when the device is implemented, the apparatuses of the exhaust gas purification unit are connected to a vacuum source.

The process of concentrating LRW by dehydration and calcination at a temperature of 600-800 ^o C, which provides for the first variant of the method, allows to obtain fine granular calcine due to more complete dehydration and calcination, which improves its loading into the melting crucible, increases the productivity of the device with decreasing time fusion of calcine with fluxing additives.

The process of synthesis of mineral-like compounds at a temperature of 1250-1800 ^o C allows you to get blocks with high chemical resistance, capable of holding radionuclides for a long time in a burial environment.

 The process of condensation of water vapor and nitric acid after cleaning the gas-vapor stream on the filter, which is equipped with the device, allows to obtain a condensate of low activity and not return it to the capacity of the initial solution, which increases the overall performance of the proposed method.

 The flue gas cleaning unit is a single chain of apparatuses connected to a vacuum pump, which creates a vacuum in the entire apparatus chain.

 The use of a spray calciner as a concentration device in combination with a high-temperature filter, which do not have mechanical moving parts, increases the reliability and service life of the entire device.

 The use of a crucible in an induction melter, the side walls and the bottom of which are assembled from two-layer water-cooled tubes assembled on a single collector and sealed with dielectric ceramics, reduces the energy lost to the melt and, due to the formation of a skull from the cooled melt on the inner surface of the crucible, eliminates corrosion of the melter material , which significantly increases the resource and safety of the melter.

 The use of a crucible in an induction melter with a melting and drain chambers, which are formed by a partition, prevents ingress of unreacted products into the ingot, which ensures the production of blocks of the required quality.

 In FIG. 1 shows a General view of the device.

 In FIG. 2 shows the design of the walls and bottom of a water-cooled crucible.

 A device for curing LRW (see Fig. 1) includes a container (1) for LRW, a compressed air apparatus (2), a concentration apparatus (spray drying and calcination apparatus) (3), automatically adjustable valves (4), a nozzle (5) , cylindrical vessel-calciner (6), product pipeline (7), high-temperature filter (8), flue gas cleaning unit (9), vacuum pump (10), mixer (11), container with fluxing additives (12), flux dispenser ( 13), intermediate flux accumulators (14), induction melter - water-cooled crucible with a fixed inductor (16), melt the main chamber (15), the drain chamber (17), the partition (18), the drain device (19), the finished unit (20), the remote connectors (22).

 The side walls and the bottom of the case of the water-cooled crucible (23) (see Fig. 2) have the following design: two-layer water-cooled tubes (24), the collector cover (21) (see Fig. 1), dielectric ceramics (25), the skull melt matrix (26), melt matrix (27).

A device for curing LRW (see Fig. 1) works as follows. To prepare a monolithic block, liquid HLW containing alkaline, alkaline-earth radionuclides and aluminum located in the LRW tank (1) was mixed by circulation or sparging with compressed air coming from the device (2), then the LRW was fed into the concentration apparatus under pressure of compressed air - spray device drying and calcination (3), through automatically controlled valves (4), and a nozzle (5), into the calciner (6), compressed air was also supplied from the device (2) there. Through the nozzle (5), LRW was sprayed with compressed air into the calciner (6). Dispersed waste in the form of droplets, moving downward, received heat due to radiation and convection from the walls of the apparatus heated to 750-800 ^o C. In this case, evaporation of moisture and partial decomposition of salts to oxides occurs at a temperature of 600-800 ^o C. The process of converting liquid droplets into solid particles occurs in the gas phase without contact with the surface of the apparatus, which prevents contact of the liquid phase with the heat-generating surface and eliminates the deposition of hard to remove hard crust and dispersed liquid HLW are converted to granular calcinate. The vapor-gas stream leaves the calciner (6) through a V-shaped product line (7) to the filter (8), where it is cleaned of the calcine particles carried away by the stream. The gas stream purified from calcine particles is sent to the exhaust gas neutralization unit (9), where it is cleaned of harmful impurities in a chain of devices connected to a vacuum pump (10). The calcine deposited on the filter is periodically removed by a reverse pulse of compressed air or by shaking, and together with calcine from the concentration apparatus it enters the flux and calcine mixer (11). To the same place from the tank with fluxing additives (12) through the flux dispenser (13) and intermediate drives (14), which work alternately, which avoids the penetration of radionuclides from the devices into the clean zone, fluxing additives are supplied in the amount necessary to obtain the final product in the form natural mineral-like material such as one of the minerals or their mixture: Aegirine, Jadeite, Aegirine-augite, Arfvedsonite, Ortit, Sherlit. From the mixer adapter (11), the mixture of calcine and flux flows by gravity into the melting chamber (15) of the water-cooled crucible (16), in which the mixture is melted. The melt of the mineral-like matrix in the melting (15) and drain (17) chambers of the water-cooled crucible (16) is prepared by starting heating a pre-loaded mixture similar in composition to the matrix (first start) or by heating a mineral-like, cooled for some reason (for example, routine maintenance) matrices (reruns). Starting heating is carried out by placing an electrically conductive starting material (50-100 g) through the flux batcher (13) and intermediate drives (14) onto the surface of the charge or the cooled matrix and applying a high-frequency electromagnetic field to the water-cooled crucible. Interacting with the electromagnetic field, the starting material begins to form a molten bath around itself, reacts with it, incorporating into its structure, and a high-frequency electromagnetic field begins to be absorbed in the formed bath of the electrically conductive melt of the mineral-like matrix, while releasing the heat required to maintain melt a given temperature and ensure the process of fusion of calcine and flux and the synthesis of a mineral-like matrix. Then, calcinate and fluxing additives are simultaneously dosed into the mixer-adapter (11) with the speeds of the ingredients, which ensure that, after the melting process, a given mineral-like matrix is obtained, which then enters the melting chamber (15). In the melting chamber, the matrix is synthesized, the melt of which flows from below under the baffle (18) into the drain chamber (17), acquiring the final composition of the mineral-like material during the movement. The water-cooled partition (18) ensures the synthesis of a homogeneous mineral-like material and ensures that unreacted flux and calcine do not get into the melt being drained from the crucible.

The synthesis of mineral-like compositions was carried out by heating the mixture of concentrated waste with fluxing additives by induction and melting at a temperature of 1300-1800 ^o C in a water-cooled crucible (16), then the finished melt was poured through a water-cooled drain device (19) into a container (20) and cooled.

 As LRW to be cured and disposed of, solutions were taken after regeneration of spent nuclear fuel from power reactors and separation of valuable components (uranium, plutonium, REE, etc.). The basic principle of selecting the composition of a matrix mineral-like composition for incorporating radionuclides is based on the maximum use of macrocomponents of liquid HLW for the synthesis of a future matrix by melting. In the case of liquid HLW, in which the salts of alkaline, alkaline-earth radionuclides and aluminum together make up the bulk of the waste components, mineral-forming fluxing additives were taken to obtain the final material such as a natural mineral: Aegirin, Jadeite, Aegirin-augit, Arfvedsonite, Ortit, Sherlit. Their crystal lattice is constructed of simple identical chains of silicon-oxygen tetrahedra, between which cations of monovalent and multivalent metals are located, and it is possible to replace not only some cations with others, but also replace some of the silicon in silicon-oxygen chains, for example, with aluminum. In this case, it becomes possible to include a higher valent cation in the crystal lattice of the mineral. These are high-temperature minerals that are part of the igneous and deepest metamorphic rocks. They are characterized by high hardness, density and high cleavage along the prism.

 In the case of liquid HLW, in which the majority of the salts are from radionuclides of fission products of nuclear fuel and products of corrosion of equipment, mineral-forming flux additives were taken to obtain the final material such as minerals: Andradit and / or Lovchorrit. In the crystal lattice of these materials there are separated "islands" of single-type silicon-oxygen tetrahedra. These minerals incorporate most of the chemical elements isomorphically into their structure and have a high affinity for nuclides, components of HLW. These materials are characterized by high hardness, isomeric forms of crystals, and relatively high density.

 In the table. 1 shows the chemical compositions of LRW simulators.

 Product No. 1 is a model solution simulating a strontium and cesium reextract. The solution contains nitric acid, hydrazine hydrate, acetamide and methanitrobenzotrifluoride, which is a solvent for fractions Cs and Sr. Product No. 2 is a model solution of a mixture of TPE and REE reextract (transplutonium and rare-earth elements) and bottoms solution of a medium-active waste evaporation unit. Product No. 3 is a model solution simulating the finate of fission products after extraction of Cs, Sr, TPE and REE. In addition, other radioactive waste may be part of LRW - these are compounds of sodium up to 40 g / l, aluminum up to 35 g / l, potassium up to 8 g / l, calcium up to 2 g / l, etc.

 In the table. 2 shows the technological modes of LRW concentration processes and the characteristics of the resulting product, ready for melting with fluxing additives. In the numbering of samples, the second digit indicates the number of the model solution, and the first digit defines the technological modes of LRW concentration processes, and sample 72 is an analogue of the known SYNROC material, which was created by calculation and processed by the prototype method.

 In the table. Figure 3 shows the calculated compositions of fluxing additives to obtain the final composition of mineral-like compositions corresponding to certain minerals and the temperature of synthesis of these minerals.

 In the table. 4 shows the compositions of the synthesized mineral-like compositions, the number of components of radioactive waste in wt.% And the phase composition of the obtained blocks.

 In the table. Figure 5 shows the calculated amounts of the used model solution and fluxes for the synthesis of mineral-like compositions of certain minerals, the productivity and specific productivity of the device. The calculated quantities of the used model solution and flux are presented in the table in the form of the ratio of LRW solution in liters and the flux required for the synthesis of a certain mineral in kilograms. Unit productivity is given by the amount of LRW solution being processed in liters per hour and flux used in kilograms per hour. The specific productivity of the device was calculated as the productivity of the LRW solution and the flux used, referred to the mirror area of the melting chamber, i.e. the installation dimensions were taken into account.

 As can be seen from the above examples, a wide range of radioactive waste was subjected to processing (Table 1), while the type of mineral-like matrices was built with the maximum use of LRW components (Tables 2 and 3). For the manufacture of monolithic blocks with solidified waste, less cheaper fluxing additives were spent than for a block made according to the prototype (example 72, Tables 2 and 3). Thus, the addition of only silicon oxide to three different concentrated concentrated LRW solutions made it possible to obtain mineral-like materials such as Egirin, Jadeite, and Arfvedsonite minerals, i.e. macro components of LRW were used to the maximum, which increases the efficiency of the process of obtaining compositions.

 In the table. Figure 4 presents the formulas of the compounds obtained and the given phase composition of blocks that correspond to natural minerals, which made it possible to obtain high properties of blocks for their long and safe storage in geological formations, and the phase composition of blocks. For comparison, the table shows the structure of the block made according to the prototype, which is a mixture of brittle separate phases of sphene, rutile, zirconolite, etc., which cannot provide a sufficiently long block strength under long-term storage and high radiation fields.

As can be seen from the data shown in table 5, the productivity of the device is from 25 to 100 l / h for the initial solutions of LRW or 7.5-29 kg / h for the produced composite. These parameters are specified in the source data and confirmed by testing in the above examples (tab. 1-4). The overall dimensions of the device in this case correspond to the internal dimensions of standard containers sent after dismantling for intermediate controlled storage and disposal. The device is equipped with special remote connectors (Fig. 1 and 3, item 22), and its weight corresponds to the performance characteristics of standard manipulators, which makes it possible to remotely mount and dismantle it with movement to containers sent to the storage. Currently used ceramic melters are an order of magnitude large, are not designed for remote installation and dismantling, and after running out of life, together with 10-15 tons of frozen highly radioactive glass, they are stored at their place of work. In addition, the performance of ceramic melters for the processed fluxed solution is 450-500 l / h, which corresponds to ≈ 250-300 l / h for the initial LRW solution. The specific productivity for a solution of such a device is 0.3-0.4 l / dm ² hours. The proposed device according to a two-stage scheme for curing LRW using a water-cooled crucible and with dimensions corresponding to the parameters of standard containers has a capacity for an initial solution of LRW from 30 to 100 l / h, while its specific productivity is in the range from 2.5 to 10.4 l / dm ² h, that is, 6-30 times higher than that of existing melters (see table. 5). The small dimensions of the device according to this method also mean low material consumption of the apparatus for installation.

 In addition, the performance of the device is limited exclusively by the specified dimensions acceptable for the manipulators and the container, and not the method used. The increase in the size of the device with a water-cooled crucible can significantly increase the overall performance of the device as a more highly efficient.

Thus, the proposed invention allows:
- to process a wide range of LRW, with virtually no restrictions on their composition and the presence of corrosive components in the compositions (Table 1);
- maximize the use of LRW components to create the structure of a monolithic solidified waste block;
- use the minimum amount of cheap fluxing additives for the process (table. 3);
- receive radioactive waste in the form of mineral-like compounds capable of retaining radionuclides for a long time in a burial environment (Table 4);
- increase the specific productivity of the device due to a more effective method of curing LRW (tables. 2 and 5);
- the use of simple circuits of devices without moving working bodies makes it possible to increase reliability and increase the overhaul life of the device (Fig. 1 and 2);
- the use of a water-cooled crucible for high-temperature synthesis allows the synthesis of materials at temperatures of 1250-1800 ^o C (table. 3), while it becomes possible to synthesize analogs of minerals, high specific productivity of synthesis is achieved, due to the formation of a skull between the walls of the melter and the aggressive melt of the material increases device resource;
- effective pre-concentration and high-temperature synthesis of materials with high specific productivity can reduce the dimensions of the device and, accordingly, reduce the material consumption and cost of the device, make it remotely replaceable, and after the resource is depleted, can be removed for intermediate storage and disposal;
- reduce the amount of secondary radioactive waste.

 Most effectively, the present invention can be applied for the curing of highly radioactive waste in order to immobilize their toxic and radioactive components and subsequent disposal in geological formations.

 At present, in Russia industrial-grade ceramic melters of the EP type are used, in which nuclides are immobilized in phosphate glass. In melters of this type, in accordance with the regulations, only a narrow range of LRW compositions can be processed. In addition, having a high overall performance, EP melters have significant dimensions and their design does not include remote dismantling and removal. After the resource is depleted, they are cooled and stored at the place of operation along with several tons of highly radioactive glass, which in the future, apparently, will require the creation of special technologies for their disposal (disposal).

 The use of induction melters allows the synthesis of materials (including glass and mineral-like), suitable for curing almost all classes of LRW. Also, this technology allows the use of compact technological equipment remotely removed for disposal.

 Implementation of the development will ensure the environmental effect and prevent the risk of radiation accidents and technological disasters associated with the storage of liquid HLW at the sites of radiochemical production.

Claims (7)

1. The method of solidification of liquid radioactive waste, including their preparation, concentration and mixing with fluxing additives, heating the resulting mixture, melting, draining the melt in a vessel, cooling the melt and forming blocks, characterized in that the concentration is carried out by spray drying and calcination at 600 - 800 ^o C, as a fluxing additives are mineral-compounds in amounts which allow to obtain the blocks in the form of a mineral-type material of natural minerals Aegirine, Jade, Aegir -avgit, arfvedsonite, orthite, Shirley, Lovchorr, Andradite or mixtures thereof, wherein the melting is carried out at 1250 the synthesis of this material - 1800 ^o C and with the direct impact of an induction field on the melt. 2. The method according to claim 1, characterized in that for the curing of liquid radioactive waste enriched with alkaline elements and aluminum, mineral-forming compounds are used as fluxing additives in quantities that allow to obtain blocks in the form of mineral-like material such as natural minerals Egirin, Jadeite, Egirin -Avgit, Arfvedsonite, Ortit, Sherlite or mixtures thereof, and the synthesis of the material is carried out at 1300 - 1800 ^o C. 3. The method according to claim 1, characterized in that for the curing of liquid radioactive waste enriched in fission products and corrosion products of equipment, mineral-forming compounds are used as fluxing additives in quantities that allow to obtain blocks in the form of mineral-like material such as natural minerals Lovchorrit and / or Andradit, and the synthesis of the material is carried out at 1250 - 1500 ^o C.  4. A device for the solidification of liquid radioactive waste, including a container for liquid radioactive waste, a concentration apparatus, an induction melter having a water-cooled drain device, a container with fluxing additives, equipped with a dispenser, a mixer, an exhaust gas purification unit, a piping system and valves, characterized in that the device is additionally equipped with a high-temperature heat-insulated filter and a pipe connecting the concentration apparatus, mixer and filter, concentration apparatus The tank is made in the form of a cylindrical vessel heated externally and located above the melter, in the upper cover of which there is a nozzle connected to a liquid radioactive waste tank and a compressed air source, the induction melter is made in the form of a water-cooled crucible with side walls and bottom transparent for an alternating electromagnetic field and bottom, inside crucible and drainage chambers are interconnected in the lower part of the crucible; the melting chamber is connected through the mixer to the concentrator Hovhan, filter and dispenser flux, the drain chamber is provided with water-cooled discharge device.  5. The device according to claim 4, characterized in that the side walls and the bottom of the body of the water-cooled crucible consist of a two-layer set of parallel water cooling tubes assembled on a single collector lid and sealed with dielectric ceramics.  6. The device according to claim 4 or 5, characterized in that the filter and the apparatus of the exhaust gas purification unit are connected to a vacuum source.  7. A device according to any one of claims 4 to 6, characterized in that each of the main components of the device is a container for liquid radioactive waste, a concentration apparatus with a filter, an induction melter, a container with fluxing additives, a dispenser, a mixer, an exhaust gas purification unit , made in the form of remotely removable and replaceable modules.

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