-
Date submitted2005-01-07
-
Date accepted2005-02-02
-
Date published2005-12-15
Physico-chemical bases of creation of sorption technologies for high-salt liquid radioactive waste management
- Authors:
- V. A. Avramenko
A theoretical model for the synthesis of nanosized sorbents in porous media of ion-exchange xerogels has been developed, which takes into account the occurrence of one or more parallel reactions of insoluble substances formation. The model describes the diffusive transfer of inter-active substances in the porous medium of xerogel and the formation of insoluble substances both in the pores of the xerogel and on the outer surface of the porous matrix. Model calculations of barium sulfate formation in the pores of amorphous porous barium silicate have been carried out. The conditions of the process of insoluble barium sulfate formation in porous xerogel medium have been determined. The results of calculations agree well with estimates made on the basis of equilibrium thermodynamics data.
-
Date submitted2005-01-07
-
Date accepted2005-02-04
-
Date published2005-12-15
Porous materials on the basis of microspheres of power ashes and their use for conditioning of liquid radioactive waste
By means of Mössbauer spectroscopy, scanning electron microscopy and thermodynamic analysis methods a detailed study of composition, morphology and properties of ash microspheres obtained at combustion of three coals (Irsha-Borodinsky, Kuznetsky and Ekibastuzsky) has been carried out. The ranges of composition of microspheres suitable for solidification of liquid radioactive waste in the form of iron-phosphate (36-94 wt.% Fe2O3) and aluminosilicate (2-20 wt.% Fe2O3) ceramics have been determined. The possibility of obtaining new materials on the basis of coal dust cenospheres and their application for immobilization of liquid radioactive waste has been shown.
-
Date submitted2005-01-12
-
Date accepted2005-02-14
-
Date published2005-12-15
Development of technologies for production of sorbents for radionuclide extraction from spent nuclear fuel and methods of radiochemical analysis and decontamination of liquid radioactive waste
New grades of inorganic sorbents based on natural materials and artificial materials (thermoxide sorbents) suitable for extraction of Cs-137 from liquid radioactive waste have been developed. The technology of selective extraction of Mo-99 from spent nuclear fuel for scientific and medical purposes using inorganic sorbents, previously developed by the Department of Radiochemistry of UGTU, has been optimized. Ag-sorbents based on thermoxide-5 carrier were developed and optimal conditions of I-131 extraction by these sorbents from aqueous solutions were determined. The technology of Mo-99 production was supplemented with a new stage of I-131 extraction from alkaline concentrate Mo-99 after desorption operation.
-
Date submitted2005-01-09
-
Date accepted2005-02-27
-
Date published2005-12-15
Technology and equipment for pipe cleaning from salt deposits
Cleaning pipes from salt deposits is a complex environmental problem. On the basis of experimental and industrial tests it has been established that electrohyde-ro-pulse technology provides effective removal of salt deposits from the inner surface of pipes and significantly reduces radiation emission from pipes.
-
Date submitted2005-01-09
-
Date accepted2005-02-04
-
Date published2005-12-15
Application of plastic track detectors for determination of fissile materials in liquid radioactive waste of NPP
- Authors:
- A. A. Dyakov
- T. N. Perekhozheva
- V. Yu. Ivanov
Methods for determining the amount of fissile materials in containers with liquid radioactive waste have been developed. The concentration of the sum of fissile materials (uranium-235 and plutonium-239) was determined by the method of plastic track detectors. This method is adapted to highly saline waters and bottom sediments. The contribution of plutonium-239 to the sum of fissile materials was determined by the radiochemical method. The methods were used to solve nuclear safety problems during decommissioning of NPPs.
-
Date submitted2005-01-19
-
Date accepted2005-02-26
-
Date published2005-12-15
Dismantling of process equipment of nuclear power facilities using explosion energy
Designs of explosive devices, schemes and technology of explosive dismantling of process equipment of nuclear power facilities being decommissioned are proposed.
-
Date submitted2005-01-04
-
Date accepted2005-02-28
-
Date published2005-12-15
Creation of technology for decontamination of radioactive sludge generated during production of gas, gas condensate and oil
- Authors:
- E. I. Krapivskii
On the territory of Russia, up to hundreds of thousands of cubic meters of oil sludge are stored in sludge storages of oil producing and refining enterprises. In the absence of modern technologies for liquefaction and utilization of oil sludge, a significant number of storage facilities have turned from a means of preventing oil pollution into a threat of large-scale pollution of soil, underground and surface water bodies. The complexity of effective utilization and liquidation of oil sludge lies in their structure. They contain oil, water, emulsions, mechanical impurities - in different ratios, and simple settling, even with heating, does not give the effect of stratification of oil sludge components.
-
Date submitted2005-01-24
-
Date accepted2005-03-02
-
Date published2005-12-15
Radioactive waste management as the most important problem of nuclear energy
- Authors:
- A. A. Persinen
Radioactive waste (RW) management is attracting more and more attention of specialists, as it poses a constant danger to human life and health for many years. According to expert estimates, the total amount of radioactive waste and spent fuel accumulated on the territory of the Russian Federation alone is more than 400mnm2 of liquid waste, more than 200mnm2 of solid waste and 8700 tons of spent fuel awaiting final disposal.
-
Date submitted2003-08-21
-
Date accepted2003-09-21
-
Date published2004-12-15
Physical and chemical basis for the creation of sorption technologies for the management of highly saline liquid radioactive waste (mathematical modeling)
- Authors:
- V. A. Avramenko
By the example of sorption-reagent materials (SRM) based on inorganic hydroxides the factors influencing the efficiency of the strontium sorption process are considered. It is shown that formation of a poorly soluble sediment in the porous system of the sorbent matrix is possible either in the form of microcrystals in the pore volume or in the form of thin X-ray amorphous layers on the pore surface, which in turn affects the selectivity of strontium extraction. The peculiarities of strontium sorption dynamics by SRM are considered. Mathematical model of strontium sorption dynamics in sorption-reagent systems is presented which allows not only to predict sorption behavior of material, form content of all system components at any moment of time and at any point of a column, but also to explain distinctive features of the process.
-
Date submitted2003-08-25
-
Date accepted2003-09-29
-
Date published2004-12-15
Development of porous glass-crystalline material based on cenospheres of energy ashes for radioactive waste disposal
- Authors:
- A. G. Anshits
The scheme of separation of cenospheres of energy ashes was developed, laboratory batches of cenospheres of stabilized composition were obtained, their morphological features were studied, macrocomponent and microelement composition was determined. Methods of obtaining porous glass-crystalline material (porous matrices) on their basis have been developed and laboratory batches of porous matrices of various modifications have been obtained. Compositions and conditions for directed solid-phase crystallization of stable mineral-like ceramics like feldspars (strontium anorthite) and feldspathoids (nepheline and cesium-bearing nepheline, pollucite) from porous matrices with sodium, cesium and strontium oxides added in ratios corresponding to real liquid radioactive wastes were determined.
-
Date submitted2003-08-05
-
Date accepted2003-09-19
-
Date published2004-12-15
Development of technologies for manufacturing sorbents for separating radionuclides from nuclear fuel waste, as well as for developing methods of radiochemical analysis and decontamination of liquid radioactive waste
The technology of selective extraction of molybdenum-99 from nuclear fuel waste for scientific and medical purposes with the use of inorganic sorbents has been developed. Inorganic sorbents based on titanium and zirconium hydroxides with anion-exchange properties were synthesized, their radiation stability and sorption properties with respect to uranium and molybdenum in sulfuric acid solutions were studied. In order to obtain Mo-99 concentrate of required radionuclide purity the sorption behavior of uranium and iodine in the process of Mo-99 extraction from solution fuel was studied. Work on synthesis and study of properties of sorbents based on natural aluminosilicates suitable for decontamination of liquid radioactive waste was continued.
-
Date submitted2003-08-07
-
Date accepted2003-09-10
-
Date published2004-12-15
Technology for cleaning tubing from radioactive solid salt deposits
Cleaning of tubing from salt deposits, which often have an increased radioactive background, is a complex environmental problem. On the basis of the experimental studies it was found that the most effective is the scheme of electrohydropulse cleaning with a discharge on the pipe wall.
-
Date submitted2003-08-21
-
Date accepted2003-09-23
-
Date published2004-12-15
Research and development of methods and technologies for safe dismantling and dismantling of decommissioned process equipment at nuclear power facilities
- Authors:
- A. A. Dyakov
The radiochemical procedures of the extraction of the nuclides U, Pu, Am and Cm and the alpha - spectrometric method of their registration have been developed to analyze actinides in the liquid radioactive waste with a high content of salts and organic impurities. The plastic track detector method has been developed to determine micro concentrations of the fissile materials U-235 and Pu-239. The above methods have been adapted to be applicable for the liquid radioactive waste analysis.
-
Date submitted2003-08-22
-
Date accepted2003-09-22
-
Date published2004-12-15
Research and development works on safe takedown procedure and handling with objects of nuclear power engineering equipment taken out of service
- Authors:
- V. V. Kalashnikov
The designs of explosive devices, schemes and technology of explosive dismantling of technological equipment of nuclear power facilities being decommissioned, increased safety.
-
Date submitted2003-08-17
-
Date accepted2003-09-13
-
Date published2004-12-15
Development of polymeric compositions for binding of radioactive waste
- Authors:
- A. A. Persinen
The properties of epoxyacrylic composition, mechanism of radiation structuring, peculiarities of radiation processes, possible fields of practical application are considered in detail.