The method of purification of aqueous radioactive solutions from radionuclides

 

(57) Abstract:

The invention relates to the purification technology of radionuclides from radioactive waste. The inventive spend cleaning radioactive water solutions at pH value of not less than 4 sorbent, which is used as a powdery amorphous titanium phosphate with a particle size of not less than 10 μm. The process of decontamination lead stage in countercurrent mode and with stirring of the solution and the sorbent for a time sufficient to ensure at each stage of purification equilibrium between the solution and the sorbent. The number of stages N is set according to the required degree of purification of radionuclides by gamma - and beta-activity, according to the relation N= (lnCRef-lnCKon)/(lnd+ln), where CRefgamma - and beta-activity of radionuclides in the source solution; CKonallowable gamma - or beta-activity of radionuclides in the final solution; the mass ratio of the sorbent and solution at each stage;dthe distribution coefficient of radionuclides by gamma - or beta-activity. The sorbent containing radionuclides, separated by filtration or centrifugation and carry out his disposal. Benefits from.

The invention relates to the purification technology from radionuclides radioactive water solutions, in particular of liquid radioactive waste (LRW) of nuclear power plants and other technological solutions with high salt background and containing impurities in the form of mineral oils and suspended solids.

When cleaning LRW containing high (>1 g/l) concentration of the cations sodium, potassium, calcium, and others, as well as impurities in the form of mineral oils and suspended solids, there is the problem of effective extraction of radionuclides due to the lack of universal sorbent, allowing to extract from a solution radionuclides compared to other competing cations, as well as in connection with the need for special stage pretreatment LRW from sediment, petroleum products, etc.

A known method of purification of aqueous radioactive solutions from radionuclides, in particular to liquid waste containing radionuclides of cesium and strontium (see RF patent 2112289, IPC 6 G 21 F 9/04, 01 J 20/02, 02 F 9/00, 1998), according to which the solution LRW serves on stage pretreatment, including units of mechanical treatment, ultrafiltration and microfiltration unit, then pass through a selective inorganic sorbent for DOS is on hold the processing of LRW in the reverse osmosis module in one stage, when the salt content is less than 1 g/l and in two stages when the salt content of more than 1 g/l with separate flow of concentrate and permeate, subjected to purification by passing through a sorbent selected from the range: of synthetic zeolite A, ion exchange resins, chabazite hexagonal patterns, natural zeolite monoclinic structure.

The disadvantages of this method are its unsuitability for LRW treatment with high salt background, the complexity and multi-stage, using a number of selective sorbents, the need for special stage pretreatment LRW from sediment and oil products, as well as the concentration of radionuclides in liquid concentrate, which amounts to about 25% of the volume of the original solution LRW and requires further processing.

There is also known a method of purification of aqueous radioactive solutions from radionuclides, in particular water activity levels (see RF patent 2090944, IPC 6 G 21 F 9/12, 1997), including the filtering of radioactive solution in the pH regulation through a combination of granulated loading of inorganic sorbents, which are used cation-phosphate of zirconium and/or titanium phosphate in hydrogen and salt forms, and volume ratio of hydrogen and salt forms cation-exchange sorbents in the combined loading is 1: 2-2: 1, the th form of the sorbent in the combined loading feature layers, when this first as the treated water layer contains the sorbent in the hydrogen form, and the second layer contains the sorbent in salt form. Combined loading may consist of a mixture of sorbents in hydrogen and salt forms. As the salt form used lithium, sodium or potassium form. To reduce the hydraulic resistance of the layer sorbents used Staropromyslovsky sorbent obtained by the Sol-gel method. Water purification by a known method are in the recirculation mode, as for one stage of filtering required degree of purification cannot be achieved.

The disadvantages of this method are its unsuitability for LRW treatment with high (>1 g/l) salt background, the need for special pre LRW purification from suspended solids and oil products, as otherwise these pollution envelop granules sorbents and prevent diffusion of radionuclides from the purified solution LRW in the sorbent. The disadvantages of this method include the use of two types of sorbents in hydrogen and salt forms, as well as the fact that they are used in granular form, having a limited contact surface. The use of sorbents in a granular view of the, because the diffusion of radionuclides into the sorbent granules having relatively large dimensions, is difficult.

The present invention is directed to the solution highly efficient purification of radionuclides LRW with high salt background, additionally containing impurities in the form of mineral oils and suspended solids.

The problem is solved in that in the method of purification of aqueous radioactive solutions from radionuclides, including interaction of the sorbent in the form of titanium phosphate in hydrogen form with the original radioactive solution in the regulation of the pH of the solution, separating the sorbent with absorbed them radionuclides from solution and subsequent disposal of long radionuclides sorbent according to the invention the titanium phosphate is used in a powdered state, the interaction of the solution and sorbent carry out stage in a period of time sufficient to ensure that at each stage of purification equilibrium between the solution and the sorbent, and the interaction of the solution and sorbent are under stirring, and the number of stages N is set according to the required degree of purification of radionuclides by gamma - and beta-activity, according to the relation:

N=(lnand is aStore; WITHKonallowable gamma - or beta-activity of radionuclides in the final solution; the mass ratio of the sorbent and solution at each stage;dthe distribution coefficient of radionuclides by gamma - or beta-activity.

The problem is solved also by the fact that the cleaning is subjected to aqueous radioactive solutions with a high content of mineral salts, with admixture of mineral oils and solid suspension.

The solution of this problem is achieved by using the sorbent composition of Tio(OH)2-2x(NRA4)xmo2Oh, where x=0.3 to 1.0, with a particle size of less than 10 microns.

On the solution of the problem is also aimed that the time of interaction of the solution and sorbent at each stage is at least 15 minutes

The solution of this problem is achieved in that the pH value of the solution to support at least 4 by introducing into the solution an alkaline component, mainly soda.

The problem is solved and the fact that the interaction between the sorbent and the solution is performed in a countercurrent, and the separation of the solution and the sorbent is carried out by filtration or centrifugation.

Solving tasks directed that kanerobot cleaning aqueous radioactive solutions with a high content of mineral salts at a pH value of not less than 4 powdery amorphous titanium phosphate composition of Tio(OH)2-2x(NRA4)xmo2Oh, where x= 0.3 to 1.0, with a particle size of less than 10 μm. The sorbent is a phosphate of Titania TiO(HPO4) or its modification, in which a part of the MIT4-groups are replaced by Oh-group, and has a high specific surface sorption that most fully realizes its ability to effectively capture of radionuclides from solution. The process of decontamination are in static conditions under stirring of the solution and the sorbent for a time sufficient to ensure at each stage of purification equilibrium between the solution and the sorbent (at least 15 min), followed by the separation of the sorbent containing radionuclides known techniques, in particular by filtration or centrifugation. Present in the initial solution, mechanical suspension cannot envelop the particles of sorbent and are separated from the purified solution LRW simultaneously with the sorbent. When removed from the solution and mineral oil. For the most efficient use of the sorbent is carried out step-wise purification of LRW from gamma - and beta-activity in the countercurrent mode of the purified solution and sorbent, where the number of stages N is set according to the ratio:

N=(lnRef-ln reduces the efficiency of sorption, reduces the distribution coefficients of radionuclides, as+ions compete with cationic substitution in the solid phase. The processing mode of the counter when the pH is not less than 4 and the number of processing stages determined according to relation (1), provides the most complete capture of radionuclides by gamma - and beta-activity in the solid phase and eliminates the formation of soluble solids. When LRW purification with high salt background is replaced by cations of metals of the protons of the sorbent and the latest move in the solution, which greatly reduces the pH of the solution. Therefore, in the process of sorption occurs the necessity of adjusting the pH. The correction is performed by the introduction of the alkaline component. The cheapest and most convenient is the use of baking soda, not changing, as a rule, the salt composition of the purified solution. For removal of phosphate ions deactivated last solution is treated with a gel of titanium hydroxide.

Before disposal the spent sorbent practical by heat treatment, which provides rigid fixation of sorbed cations, are not promoted in the future as in weakly acidic and weakly alkaline solutions, what with the project.

The nature and advantages of the invention can be illustrated by the following examples.

In all examples, the number of stages is determined based on the required degree of purification of radionuclides by gamma - and beta-activity, according to the relation N= (lnRef-lnKon)/(lnKd+ln), where CKonfor the gamma activity is assumed to be 80 Bq/l, andKonfor beta activity is assumed to 35 Bq/L. at the same time as working choose the number of stages number of stages, providing the desired degree of purification and gamma - and beta-activity, and several successive stages together in a cycle. In the countercurrent mode (example 6) the process is conducted with use in a subsequent cycle of the sorbent from the previous cycle.

Example 1.

The number of stages of treatment, calculated from equation (1) is 2. For the purified solution WITHRefgamma activity is 45510 Bq/l, andReffor beta activity is 11380 Bq/L. the Mass ratio of the sorbent and solution =1:75, the distribution coefficients Kdgamma - and beta-activity is equal to the average 1800 and 1300 cm3/,

Stage 1. 46 ml of the original radioactive solution with the sole is asny material with a particle size of less than 10 μm and a water content of 46.7%. The sorbent composition corresponds to the connection Toro4mo2O (x=1). In the process of interaction of the sorbent with a radioactive solution, the pH value is reduced to 5. After 15 min, after the establishment of equilibrium between the solution and the sorbent solid phase is separated from the solution by centrifugation. The degree of purification of the solution from radionuclides is 96,03% gamma activity and 94,60% beta-activity. Residual concentrations of radionuclides in solution is 1807 Bq/l for gamma activity and 615 Bq/l for beta activity. The used sorbent is sent for disposal.

Stage 2. 40 ml of the solution obtained by centrifugation at the previous stage, is treated under stirring of 0.533 g of sorbent, similar to that used in stage 1, for 15 minutes In the process of interaction of the sorbent with a radioactive solution pH value equal to 5, to support the introduction of the suspension of the necessary quantity of sodium carbonate solution. Then the solid phase is separated from the solution by centrifugation. The degree of purification of the solution from radionuclides is 99,84% gamma activity and 99,68% beta-activity. Residual concentrations of radionuclides in solution is 73 Bq/l for gamma activity and 34 B is

The main parameters of the purification method and the results obtained in this example and examples 2 to 8 are summarized in table.

Example 2.

Conduct cleanup of radioactive solution under the conditions of example 1, except that the feed solution additionally contains 0.5 g/l suspended solids - corrosion products of metals. The degree of purification of the solution from radionuclides is 99,84% gamma activity and 99,70% beta-activity. Residual concentrations of radionuclides in solution is 74 Bq/l for gamma activity and 33 Bq/l for beta activity.

Example 3.

Conduct cleanup of radioactive solution under the conditions of example 2, except that in the original solution pre-enter to 0.04 wt.% oil products. The degree of purification of the solution from radionuclides is 99,84% gamma activity and 99,70% beta-activity. Residual concentrations of radionuclides in solution is 72 Bq/l for gamma activity and 34 Bq/l for beta activity. The concentration of oil products in purified solution is less than 0.1 mg/l, well below the standards established for fishery waters.

Example 4.

Conduct cleanup of radioactive solution in terms of p
)0,56mo2O (x= 0,56). The degree of purification of the solution from radionuclides is 99,84% gamma activity and 99,69% beta-activity. Residual concentrations of radionuclides in solution is 73 Bq/l for gamma activity and 35 Bq/l for beta activity.

Example 5.

Conduct cleanup of radioactive solution under the conditions of example 2, except that as a sorbent use titanium phosphate composition of TiO(OH)1,4(HPO4)for 0.3mo2O (x=0.30). When determining the number of stages of clearing the value of the distribution coefficient Kdgamma - and beta-activity is equal to the average 1800 and 1400 cm3/, the Degree of purification of the solution from radionuclides is 99,83% gamma activity and 99,73% beta-activity. Residual concentrations of radionuclides in solution is 77 Bq/l for gamma activity and 31 Bq/l for beta activity.

Example 6.

The number of stages of treatment, calculated from equation (1) equals 4. For the purified solution WITHRefgamma activity is 164600 Bq/l, andReffor beta activity is 41150 Bq/L. the Mass ratio of the sorbent and solution =1:40, the distribution coefficients Kdabout the use of sorbent applied mode of the counter with the number of cleaning cycles, equal to 2.

Cycle 1.

Stage 1. 47 ml of the original radioactive solution with a salinity of 33 g/l and pH=8 is treated under stirring for 15 min is 1.175 g of sorbent, similar to that used in example 1. In the process of interaction of the sorbent with a radioactive solution pH is lowered to 6. Then the solid phase is separated from the solution by filtration. The degree of purification of the solution from radionuclides is 87,77% gamma activity and 87,54% beta-activity. Residual concentrations of radionuclides in solution is 20131 Bq/l for gamma activity and 5127 Bq/l for beta activity. The used sorbent is sent for disposal.

Stage 2. 41 ml of the filtrate obtained in stage 1, is treated under stirring for 15 min 1,012 g of sorbent, similar to that used in stage 1. In the process of interaction of the sorbent with a radioactive solution pH value equal to 5, to support the introduction of the suspension of the necessary quantity of sodium hydroxide solution. Then the solid phase is separated from the solution by filtration. The degree of purification of the solution from radionuclides corresponds 98,44% gamma activity and 98.34 per cent for beta activity. Residual concentrations of radionuclides in solution is 2568 B is">

Stage 3. 36 ml of the filtrate obtained in stage 2, is treated under stirring for 15 min 0,90 g of sorbent, similar to those used in the previous stages. In the process of interaction of the sorbent with a radioactive solution pH equal to 6, to support the introduction of the suspension of the necessary quantity of sodium hydroxide solution. Then the solid phase is separated from the solution by filtration. The degree of purification of the solution from radionuclides is efficiency of 99.78% gamma activity and 99,74% beta-activity. Residual concentrations of radionuclides in solution is 362 Bq/l for gamma activity and 107 Bq/l for beta activity. Separated from the solution sorbent used for further purification of a new portion of the solution in the loop 2 in stage 1.

Stage 4. 30 ml of the filtrate obtained in stage 3, is treated under stirring for 15 min 0.75 g of sorbent, similar to those used in the previous stages. In the process of interaction of the sorbent with a radioactive solution pH value equal to 5, to support the introduction of the suspension of the necessary quantity of sodium hydroxide solution. Then the solid phase is separated from the solution by filtration. The degree of purification of the solution from radionuclides is of 99.97% for gamma-ray activity and the minute and 21 Bq/l for beta activity. The purified solution is drained. Separated from the solution sorbent used for further purification of a new portion of the solution in the loop 2 in stage 2.

Cycle 2.

Stage 1. 30 ml new portion of the original radioactive solution is treated under stirring for 15 min 0,789 g of sorbent after using it on stage 3 in cycle 1. In the process of interaction of the sorbent with a radioactive solution, the pH value is reduced to 7. Then the solid phase is separated from the solution by filtration. The degree of purification of the solution from radionuclides is 84,36% gamma activity and 84,98% beta-activity. Residual concentrations of radionuclides in solution is 25743 Bq/l for gamma activity and 6181 Bq/l for beta activity. Separated from the solution sorbent sent for disposal.

Stage 2. 25 ml of the filtrate obtained in stage 1 of cycle 2, is treated under stirring for 15 min 0.64 g of sorbent after using it on stage 4 in cycle 1. In the process of interaction of the sorbent with a radioactive solution pH value equal to 5, to support the introduction of the suspension of the necessary quantity of sodium hydroxide solution. Then the solid phase is separated from the solution by filtration. The degree of purification of the solution from radionuclide is 3868 Bq/l for gamma activity and 934 Bq/l for beta activity. Separated from the solution sorbent sent for disposal.

Stage 3. 20 ml of the filtrate obtained in stage 2 of cycle 2, the process of 0.49 g of sorbent, similar to that used on stages 1-4 in the cycle 1. In the process of interaction of the sorbent with a radioactive solution pH value equal to 5, to support the introduction of the suspension of the necessary quantity of sodium hydroxide solution. Then the solid phase is separated from the solution by filtration. The degree of purification of the solution from radionuclides is 99,69% gamma activity and 99,67% beta-activity. Residual concentrations of radionuclides in solution is 510 Bq/l for gamma activity and 136 Bq/l for beta activity. Separated from the solution of the sorbent can be used for further purification of a new portion of the radioactive solution.

Stage 4. 15 ml of the filtrate obtained in stage 3 of cycle 2, is treated under stirring for 15 min 0,366 g original sorbent similar to that used on stages 1-4 of cycle 1. In the process of interaction of the sorbent with a radioactive solution pH equal to 4, to support the introduction of the suspension of the necessary quantity of sodium hydroxide solution. Then the solid phase is separated from the solution by filtration. Degree ocidate radionuclides in solution is 49 Bq/l for gamma activity and 21 Bq/l for beta activity. The purified solution is drained. Separated from the solution of the sorbent can be used for further purification of a new portion of the radioactive solution.

Example 7.

Conduct cleanup of radioactive solution under the conditions of example 2. The difference is that for the extraction of phosphate ions 30 ml of purified after stage 2 of the solution process svezheosazhdennoi hydroxide titanium weight to 0.011 g in terms of Tio2. The content of phosphate ion in the solution before processing svezheosazhdennoi hydroxide of titanium in terms of P2O5equal to 12.6 mg/l and after treatment of a solution of phosphate ions in it is not detected. The degree of purification of the solution from radionuclides is 99,83% gamma activity and 99,68% beta-activity. Residual concentrations of radionuclides in solution is 77 Bq/l for gamma activity and 34 Bq/l for beta activity.

Example 8.

Conduct cleanup of radioactive solution in terms of cycle 1 of example 6 except that the pH of the suspension does not regulate, WITHRefgamma activity is 146400 Bq/l, andReffor beta activity is 36600 Bq/L. the Degree of purification of the solution from radionuclides is 99,74% gamma activity and 99,48% beta activestills. After stage 4 further decontamination solution.

From the above examples and tables, it follows that the claimed method in comparison with the prototype provides a highly efficient purification of liquid radioactive waste containing high salt background, mineral oils and solids suspension. Residual radionuclide concentration in the purified solution by gamma-activity does not exceed 80 Bq/l, and beta-activity - 35 Bq/L. in Addition, the advantages of the claimed method are the versatility of the materials used, as in the process of LRW treatment is captured and gamma - and beta-activity that does not require sequential processing of technological solutions for more specific sorbents. The method allows to provide a reliable form of disposal of spent sorbent and is characterized by the simplicity of the hardware design process.

1. The method of purification of aqueous radioactive solutions from radionuclides, including interaction of the sorbent in the form of titanium phosphate in hydrogen form with the original radioactive solution in the regulation of the pH of the solution, separating the sorbent with absorbed them radionuclides from solution and disposal of sorbent, characterized in that h is Adino over time, sufficient to ensure that at each stage of purification equilibrium between the solution and the sorbent, the interaction of the solution and sorbent are under stirring, the number of stages N is set according to the required degree of purification of radionuclides by gamma - and beta-activity, according to the relation N= (lnCRef-lnKon)/(lnd+ln), where CRefgamma - and beta-activity of radionuclides in the source solution; CKonallowable gamma - or beta-activity of radionuclides in the final solution; the mass ratio of the sorbent and solution at each stage;dthe distribution coefficient of radionuclides by gamma - or beta-activity.

2. The method according to p. 1, characterized in that the purification is subjected to aqueous radioactive solutions with a high content of mineral salts, with admixture of mineral oils and solid suspension.

3. The method according to p. 1 or 2, characterized in that use, the sorbent composition of TiO(OH)2-2x(HPO4)xnH2O, where x= 0.3 to 1.0, with a particle size of less than 10 microns.

4. The method according to any of paragraphs. 1-3, characterized in that the reacting solution and sorbent at each stage is at least 15 minutes

5. The method according to any of paragraphs. 1-4, from the and, mostly soda.

6. The method according to any of paragraphs. 1-5, characterized in that the interaction between the sorbent and the solution is performed in a counter.

7. The method according to any of paragraphs. 1-6, characterized in that the separation of the solution and the sorbent is carried out by filtration or centrifugation.

8. The method according to any of paragraphs. 1-7, characterized in that the end solution is treated with a gel of titanium hydroxide.

 

Same patents:
The invention relates to the field of processing of intermediate level liquid waste from nuclear power plants, nuclear power plants, reprocessing plants, nuclear research centers

The invention relates to the chemical treatment technology solutions from radioactive elements

The invention relates to the treatment of aqueous media from radioactive contaminants by sorption and can be used in the process of operation of energy transport facilities

The invention relates to the purification of the environment, namely to extract radioactive isotopes from contaminated soil

The invention relates to radiochemistry, namely, the purification of liquid radioactive waste

The invention relates to nuclear technology, namely, to remove from the circuit of a nuclear reactor of potentially hazardous substances

The invention relates to the production of sorbents from lignocellulosic plant raw material, which can be used for cleaning liquid media (cross water, oil, agricultural products, particularly milk), land reclamation and agricultural land contaminated with radionuclides

FIELD: recovery of liquid radioactive wastes.

SUBSTANCE: proposed method includes bringing liquid radioactive wastes in contact with matrix saturated with selective ion-exchange material (solid extracting agent). Glass-crystal material with open porous structure is used as matrix for the purpose. Matrix material is produced from hollow glass-crystal cene spheres formed from mineral particles of volatile ash produced as result of black coal combustion and saturated with selective ion-exchange material.

EFFECT: facilitated procedure of radionuclide extraction.

5 cl, 1 tbl, 5 ex

FIELD: recovery of liquid radioactive wastes.

SUBSTANCE: proposed method includes treatment of radioactive wastes by heavy-metal ferrocyanide and separation of sediment obtained. In the process liquid radioactive wastes are treated with heavy-metal ferrocyanide formed upon introduction of potassium ferrocyanide and bivalent nickel and/or copper and iron salts taken in amount abundant with respect to stoichiometric quantity. Clarified solution is treated with oxidant upon separation of sediment and filtered through catalytic material containing manganese dioxide. Then filtered-off solution is passed through highly acid cationite in Na-form and highly basic anionite in Cl-form.

EFFECT: enhanced decontamination quality.

5 cl, 1 tbl, 7 ex

FIELD: reactive sorbents.

SUBSTANCE: liquid is conditioned at pH 4-6 and then is brought into contact with chelating ion-exchange resin composed of grafted polyazocycloalkanes at temperature above or equal to 60°C.

EFFECT: enhanced metal removal efficiency.

35 ex, 9 dwg, 9 tbl, 5 ex

FIELD: processing of liquid radioactive wastes.

SUBSTANCE: the proposed method for cleaning of liquid radioactive wastes includes their processing with absorber-sorbent. Ash wastes are used as the absorber-sorbent. The ash wastes are introduced into liquid radioactive wastes in the stage of their neutralization at pH = 0.5-2 at the flow rate, ensuring the ratio of S : L = 1 : (15-50). Then the obtained suspension is separated into the liquid and solid phases.

EFFECT: increased degree of cleaning from radionuclides and enhanced separation rate of produced pulps.

4 cl, 1 tbl, 11 ex

FIELD: medicine.

SUBSTANCE: invention relates to application of pectin solution as detergent for skin and hair in radioactive and environmentally hazardous regions. Pectin containing in solution due to chelating action bonds to heavy metal ions to form stable compounds (micelles) having very large size and prevents transferring thereof trough transdermal barrier. Formed micells may be easily removed from human body.

EFFECT: new detergent for skin and hair useful in radioactive and environmentally hazardous regions.

2 ex, 5 tbl

FIELD: methods of the sorption decontamination of waters from the radioactive impurities.

SUBSTANCE: the invention is pertaining to the method of the sorption decontamination of waters from the radioactive impurities. The method of decontamination of the water from radiostrontium includes the treatment of the water with a sorbent based on the burned bauxite ore. At that the ore is burned together with calcium -magnesium lime - CaCO3·MgCO3 and sodium soda salt - Na2CO3 at the temperature of no less than 1200°C and flushed with the water to remove the solvable sodium compounds. It is preferable, that the mixture of the bauxite ore is subjected to burning with calcium-magnesium lime and sodium soda salt in the mass ratio of 1 : 0.55-0.60 : 0.055-0.060. The method ensures an increased effectiveness of removal of the radiostrontium at usage of the initial bauxite ore without lowering of effectiveness of the water decontamination from radiocesium, and also allows to reduce considerably the amount of the spent sorbents, which are subjected to disposal.

EFFECT: the invention ensures an increased effectiveness of removal of radiostrontium from the water at usage of the initial bauxite ore without lowering of effectiveness of the water decontamination from radiocesium, allows to reduce considerably the amount of the spent sorbents, which are subjected to disposal.

2 cl, 10 ex

FIELD: environment control including environment protection in atomic industry.

SUBSTANCE: proposed method for decontaminating radioactive aqueous solutions from radionuclides includes at least one contact of solution with complexing sorbent that has solid-medium immobilized active polymeric layer condensed with chelates. Medium is chosen from following group: activated cellulose; synthetic copolymers with divinyl benzene, activated chloromethyl or hydroxymethyl, or chlorosulfonic groups. Active sorbing layer has ethylenediamine or diethylene tridiamine, or tetraethylene pentaamine, or polyethylene polyamine with copolymers; chelates are chosen from group incorporating carboxyl-containing chelates, phosphonic-group chelates, and hydroxyl-containing chelates. Proposed method enables extraction of radionuclides both in ionic and colloidal condition from solutions doped with highly concentrated impurities; sorbent used for the purpose retains its sorbing properties upon repeated regenerations and is capable of decontaminating solutions both in dynamic and static modes with different pH of solutions being decontaminated.

EFFECT: enlarged functional capabilities.

11 cl, 3 tbl

FIELD: technology of handling of the liquid nuclear wastes of the nuclear fuel and power cycle; methods of reprocessing of the liquid nuclear wastes.

SUBSTANCE: the invention is pertaining to the procedure of the liquid nuclear wastes handling of the nuclear fuel and power cycle and may be used during reprocessing of the liquid nuclear wastes (LNW). The method includes the preliminary concentration, ozonization, microfiltration of the vat residue with fractionation of the permeate and the concentrate and the ion-selective purification of the permeate using the ion-selective a sorbent. At that the microfiltration is conducted at least in two stages: the permeate of each previous stage of the microfiltration is directed to the microfiltration as the source solution for the subsequent stage of the microfiltration, and at the final stage of the permeate from the microfiltration is sent to the utilization. The concentrate produced at each next stage of the microfiltration is mixed with the source solution of the previous stage of the microfiltration. The concentrate produced at the first stage of the microfiltration is directed to the conditioning and dumping. The ion-selective sorbent is added in the permeate of the previous stage of the microfiltration before the final stage of the microfiltration. The invention ensures: reduction of the volume of the liquid nuclear wastes due to the deep purification of the LNW with the high saline share from the radionuclides and extraction of the radionuclides in the compact form of the sparingly soluble compounds at the corresponding increase of the factor of purification of the salts extracted at the stage of the vat residue treatment; reduction and optimization of the consumption of the permeate and concentrate interacting with the source solution as well as produced at the further stages.

EFFECT: the invention ensures: reduction of the volume of the liquid nuclear wastes; the deep purification of the LNW with the high saline share from the radionuclides and extraction of the radionuclides in the compact form of the sparingly soluble compounds at the corresponding increase of the factor of purification of the salts extracted at the stage of the vat resudue treatment; reduction and optimization of the consumption of the permeate and concentrate interacting with the source solution ands produced at the further stages.

FIELD: nuclear-industry radiochemical enterprises for recovering and immobilizing gaseous radioactive wastes.

SUBSTANCE: sorbent used for entrapping radioactive iodine from gas-aerosol stream running from irradiated nuclear fuel cutting-and-dissolving unit has porous base impregnated with nitric acid silver salt (AgNO3); used as sorbent base is porous silicon carbide of 30 to 60% porosity.

EFFECT: enhanced corrosion and mechanical resistance of material in chemically active media.

1 cl, 2 dwg, 3 tbl

FIELD: environmental protection.

SUBSTANCE: invention relates to means and methods of integrated degassing, disinfection, and shielding of sites and zones, where presence of high-activity poisonous substances, poison-gases, chemical weapons, pathogenic microorganisms, their vital activity toxic products, insects (including carriers of human and animal diseases), radioactive substances are revealed or suspected, and also to means and methods to extinguish burning of inflammable liquids and to prevent in inflammation of spills of inflammable liquids. Multifunctional foam composition of invention includes, as active substance, 0.1-5% of didecyldimethylammonium halide clatrate with urea. Use of indicated clatrate provides simultaneous effect of foam compositions, wherein clatrate acts both as multifunctional active substance and as foaming agent. Invention can further be used to eliminate consequences of use of weapons of mass destruction and to eliminate consequences of man-made accidents and emergency situations.

EFFECT: expanded protection possibilities.

24 cl, 3 tbl, 6 ex

Up!