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Grazyna Zakrzewska-trznadel - One of the best experts on this subject based on the ideXlab platform.
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Advances in membrane technologies for the treatment of Liquid Radioactive Waste
Desalination, 2013Co-Authors: Grazyna Zakrzewska-trznadelAbstract:Abstract The work presents a review on the membrane methods recently introduced into the nuclear technology against the background of the other, commonly applied separation techniques, with indications of the possibilities and prospects for their further developments. Particular attention was paid to the pressure-driven processes, e.g., ultrafiltration and reverse osmosis, which were studied in laboratory and pilot scales at Institute of Nuclear Chemistry and Technology, Warsaw. Verification of the potential application of reverse osmosis in the industrial scale for the treatment of Liquid low- and intermediate-level Radioactive Wastes was accomplished with the installation designed and constructed for Radioactive Waste Management Plant at Świerk, Warsaw. A great attention was given to perspective membrane processes for the treatment of high-level Liquid Waste and partitioning of actinides, such as Liquid membranes and membrane solvent extraction, as well as to membrane contactors that are modern apparatus approach for unit operations involving application of membranes.
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30 Radioactive Waste Processing: Advancement in Pressure-Driven Processes and Current World Scenario
2009Co-Authors: Grazyna Zakrzewska-trznadelAbstract:30.1 Radioactive Waste Treatment by Membrane Methods 844 30.1.1 Membrane Selection for Nuclear Applications 844 30.1.2 System Design 845 30.1.3 Process Operation—Considerations from Radiological Safety Point of View 846 30.1.3.1 Process Control 846 30.1.3.2 Radiological Protection Requirements 847 30.1.3.3 Membrane Control 848 30.1.3.4 Decontamination of the Space and Equipment 850 30.2 Membrane Processes Employed for Liquid Radioactive Waste Treatment 850 30.2.1 Reverse Osmosis 850 30.2.1.1 Three-Stage Reverse Osmosis Installation for Lowand Intermediate-Level Radioactive Wastes Processing 850 30.2.1.2 Other Applications 854 30.2.2 Nanofiltration 854 30.2.3 Ultrafiltration 854 30.2.3.1 Removal of Radionuclides from Water Solutions by Ultrafiltration=Complexation 858 30.2.3.2 Treatment of Original Radioactive Waste 860 30.2.3.3 Pilot Plant Experiments 863 30.2.4 Microfiltration 866 30.2.5 Membrane Distillation 866 30.3 Future of Membrane Processes in Nuclear Technology 872 30.3.1 Liquid Radioactive Waste Processing by Membrane Processes: Advantages and Limitations 872 30.3.2 New Fields of Application of Membrane Processes in Nuclear Industry 873 30.3.2.1 Removal of Tritium from Nuclear Waste (Liquid and Gaseous Effluents) 873 30.3.2.2 Isotope Separation 874 30.3.2.3 Gaseous Radioactive Wastes—Noble Gases Separation 875 Nomenclature 875 Abbreviations 875 References 876
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Membrane processes in nuclear technology-application for Liquid Radioactive Waste treatment
Separation and Purification Technology, 2001Co-Authors: Grazyna Zakrzewska-trznadel, Marian Harasimowicz, Andrzej G. ChmielewskiAbstract:Membrane methods can be considered as the most energy-saving separation techniques. Separation abilities of membranes allow the elimination of many non-effective and energy consuming methods and their replacement by new, modern technologies, friendly environment friendly. An application of membrane methods for Liquid Radioactive Wastes treatment requires solving many problems connected with the proper selection of the membranes, membrane modules and other equipment according local conditions: chemical and radiochemical composition of the effluents treated, their activity and total salinity. The installations working in nuclear industry have to fulfil very strict requirements. They ought to be reliable, constructed from special materials defined by separate regulations. Only small number of manufacturers of membrane devices has for their products the certificates of International Atomic Energy Agency. Reverse osmosis (RO) as a method for Liquid Waste treatment has been examined at laboratory and pilot plant installations. The experience with the process led to design and construction of the industrial plant, 1 m3 capacity, composed of three RO stages. The plant will be included into the system for Liquid Radioactive Wastes purification operating at Institute of Atomic Energy in Swierk near Warsaw, treating the Liquid Waste from all of Poland. Membrane distillation (MD) can be an alternative for Liquid Radioactive Waste concentration. On the basis of previous laboratory tests a pilot plant for Liquid Radioactive Wastes concentration employing direct contact MD was constructed. Pilot plant experiments showed MD is interesting solution for Liquid low-level Radioactive Waste treatment. As MD is characterised by high retention, large decontamination factors were obtained in separation of radionuclides, which are present in Liquid low-level Radioactive Wastes mainly in an ionic form. The RO and MD plants for Liquid low level Radioactive Wastes treatment are presented in the paper and the evaluation of both methods, as well.
Andrzej G. Chmielewski - One of the best experts on this subject based on the ideXlab platform.
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Membrane processes in nuclear technology-application for Liquid Radioactive Waste treatment
Separation and Purification Technology, 2001Co-Authors: Grazyna Zakrzewska-trznadel, Marian Harasimowicz, Andrzej G. ChmielewskiAbstract:Membrane methods can be considered as the most energy-saving separation techniques. Separation abilities of membranes allow the elimination of many non-effective and energy consuming methods and their replacement by new, modern technologies, friendly environment friendly. An application of membrane methods for Liquid Radioactive Wastes treatment requires solving many problems connected with the proper selection of the membranes, membrane modules and other equipment according local conditions: chemical and radiochemical composition of the effluents treated, their activity and total salinity. The installations working in nuclear industry have to fulfil very strict requirements. They ought to be reliable, constructed from special materials defined by separate regulations. Only small number of manufacturers of membrane devices has for their products the certificates of International Atomic Energy Agency. Reverse osmosis (RO) as a method for Liquid Waste treatment has been examined at laboratory and pilot plant installations. The experience with the process led to design and construction of the industrial plant, 1 m3 capacity, composed of three RO stages. The plant will be included into the system for Liquid Radioactive Wastes purification operating at Institute of Atomic Energy in Swierk near Warsaw, treating the Liquid Waste from all of Poland. Membrane distillation (MD) can be an alternative for Liquid Radioactive Waste concentration. On the basis of previous laboratory tests a pilot plant for Liquid Radioactive Wastes concentration employing direct contact MD was constructed. Pilot plant experiments showed MD is interesting solution for Liquid low-level Radioactive Waste treatment. As MD is characterised by high retention, large decontamination factors were obtained in separation of radionuclides, which are present in Liquid low-level Radioactive Wastes mainly in an ionic form. The RO and MD plants for Liquid low level Radioactive Wastes treatment are presented in the paper and the evaluation of both methods, as well.
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membrane technologies for Liquid Radioactive Waste treatment
Czechoslovak Journal of Physics, 1999Co-Authors: Andrzej G. Chmielewski, Marian Harasimowicz, Grazyna ZakrzewskatrznadelAbstract:The paper deals with some problems concerning reduction of radioactivity of Liquid low-level nuclear Waste streams (LLLW). The membrane processes as ultrafiltration (UF), seeded ultrafiltration (SUF), reverse osmosis (RO) and membrane distillation (MD) were examined. Ultrafiltration enables the removal of particles with molecular weight above cut-off of UF membranes and can be only used as a pre-treatment stage. The improvement of removal is achieved by SUF, employing macromolecular ligands binding Radioactive ions. The reduction of radioactivity in LLLW to very low level were achieved with RO membranes. The results of experiments led the authors to the design and construction of UF+2RO pilot plant. The development of membrane distillation improve the selectivity of membrane process in some cases. The possibility of utilisation of Waste heat from cooling system of nuclear reactors as a preferable energy source can significantly reduce the cost of operation.
Dmitry Marinin - One of the best experts on this subject based on the ideXlab platform.
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Sorption-Reagent Method in Liquid Radioactive Waste Management
MRS Proceedings, 2002Co-Authors: Valentin Avramenko, Dmitry Marinin, V. V. Zheleznov, Elena V. Kaplun, T. A. Sokol’nitskaya, And Anna A. YukhkamAbstract:Methods of Liquid Radioactive Waste (LRW) decontamination from radionuclides including their co-precipitation at specific conditions or adsorption on selective sorption materials are well known and extensively used in LRW management technologies. At the same time, it was shown in a number of papers that some forms of organic and inorganic ionexchangers react with solutions containing specific components that results in formation of virtually insoluble precipitates inside the sorbent matrix or on its surface. Here in some cases the sorbent selectivity to some radionuclides increases substantially. The sorption-reagent materials synthesized for decontamination purposes are the most highly selective in regard to such difficult to remove radionuclides as strontium-90 and cobalt-60. It was shown by comparative analysis of radionuclide removal efficiency by traditional selective sorbents and developed sorption-reagent materials that the latter have the highest distribution coefficients in systems too complex for “pure” sorption/ion-exchange decontamination. For example, the sorption-reagent materials have strontium distribution coefficients several dozens higher than those of commercially available sodium titanates and silicotitanates. The mechanism of radionuclide sorption on sorption-reagent materials of different types was studied. It was shown that this is a multi-stage process and the course of different stages of chemical reactions and sorption is determined by the parameters of medium from which radionuclides are sorbed. It was also shown that these materials application in Liquid Radioactive Waste management enables one to develop simple technological setups combining the advantages of sorption and precipitation methods. One of the main fields of the sorption-reagent materials application can be decontamination of high-salinity Radioactive Waste formed whether as a result of ionexchanger filters regeneration in LRW management systems or in reverse osmosis installations. Use of sorption-reagent materials for high-salinity Waste management enables one to reduce several ten-fold or even hundred-fold the volume of solid Radioactive Waste (SRW) to be sent for final disposal and, therefore, to decrease the cost of LRW management. The approach consisting in combined application of reverse-osmosis and sorption-reagent methods for LRW decontamination is suggested.
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studies of sorbent ion exchange materials for the removal of Radioactive strontium from Liquid Radioactive Waste and high hardness groundwaters
Waste Management, 2000Co-Authors: Dmitry Marinin, Garrett N BrownAbstract:Different sorbents were studied in terms of their full-scale applicability for Radioactive strontium removal in low-level Liquid Radioactive Waste (LLRW) management. The following types of sorbent/ion-exchange materials were investigated: natural zeolite–clinoptilolite, modified natural clinoptilolite, synthetic zeolites, new synthetic crystalline materials selective to strontium, ion-exchange resins, and modified fiber sorbents. Simulated solutions for experimental tests were prepared according to the composition of one of the facilities at the Hanford nuclear site (Richland, WA, USA). The following experiments were performed at different concentrations of strontium and competing elements (calcium, on the first hand): batch tests for determination of strontium distribution coefficients, sorbent/ion-exchanger selectivity to strontium in the presence of calcium, and kinetic measurements of strontium uptake. Modifications of Amberlite and Duolite ion-exchange resins (Rohm and Haas, USA) and new synthetic crystalline materials — silicotitanate IE-911 (UOP, USA) and sodium titanate (Allied Signal, USA) — showed the highest distribution coefficients of strontium (Kd∼ 2×104–4×105 ml/g). For all materials, the Kd decreased significantly with increased calcium concentration. On the other hand, each of these sorbents showed poor selectivity to strontium in the presence of calcium. Newly developed sorbents (Institute of Chemistry, Vladivostok, Russia) based on a fiber matrix (FM and FP) showed the best relative selectivity to strontium followed by the natural zeolite (clinoptilolite extracted and produced in the USA). Synthetic zeolites (IE-96, TIE-96) had moderate values of both parameters (distribution coefficient and selectivity). Fiber sorption materials were also absolute leaders in kinetic measurements removing 40% to 60% of the strontium from solution within a few minutes.
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New sorbents and technologies for Liquid Radioactive Waste management
MRS Proceedings, 1996Co-Authors: Dmitry Marinin, Valentin Avramenko, V. I. Sergienko, V. Yu Glushchenko, V. A. Vasilevskiy, V. V. ZheleznovAbstract:The possibilities for using various technologies for Liquid Radioactive Waste (LRW) management were considered. Technologies based on the application of sorbents highly selective to radionuclides were shown to have good prospects. Possible ways of increasing selective sorbent efficiency in cleaning radionuclide-polluted waters of various types were examined. The results of studying new high-selective sorbents produced in the Institute of Chemistry FEDRAS are given. The use of these sorbents enables one to treat LRW of various types in a single stage. The results of testing a sorption filter installation for management of LRW produced during operation, repair and disposal of nuclear reactors are presented. Use of this installation resolves a major portion of LRW disposal problems.
Valentin Avramenko - One of the best experts on this subject based on the ideXlab platform.
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Processes for treatment of Liquid Radioactive Waste containing seawater
Radiochemistry, 2017Co-Authors: Valentin Avramenko, T. A. Sokol’nitskaya, A. M. Egorin, E. K. Papynov, Ivan G. Tananaev, V. I. SergienkoAbstract:The main sources of formation of Liquid Radioactive Waste (LRW) containing seawater are determined, and the main problems arising in management of such Waste are analyzed. Sorption methods for removing long-lived Cs and Sr radionuclides from highly mineralized (>1 g L–1) LRW are determined. The main physicochemical and sorption characteristics, advantages, and drawbacks of candidate sorbents for removing Cs and Sr radionuclides are described. Examples of using SRM and VS-5 chemical reaction sorption materials developed for removing Sr from LRW with the mineralization of up to 60 g L–1 are given. The results of studying composite materials based on BaSiO3 and resorcinol–formaldehyde resins, intended for removing Cs and Sr radionuclides from seawater, are analyzed. Composite sorbents of such type efficiently remove Cs and Sr radionuclides from seawater. Processes developed by the authors and brought into practice at various plants of the Far East for treatment of multicomponent LRW formed in the course of operation, repair, and decommissioning of nuclear-powered surface ships and submarines are described.
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Application of sorption-reagent materials in the technology of Liquid Radioactive Waste treatment
Theoretical Foundations of Chemical Engineering, 2016Co-Authors: Valentin Avramenko, V. I. Sergienko, T. A. Sokol'nitskayaAbstract:Some examples of sorption-reagent materials and variants of their application in the practice of treating Liquid Radioactive Waste have been considered. The data on the strontium sorption on samples of a sorption-reagent material under dynamic conditions at different degrees of dilution and different concentrations of seawater have been presented. These data demonstrate that the most efficient practical applications of sorption-reagent materials consist of decontaminating of seawater concentrates of strontium radionuclides. This task is stated during treatment of Liquid Radioactive Waste (LRW) streams at the Fukushima-1 NPP (Japan), where reverse osmosis concentrates constitute the main problem of localization of the aftermath of the disaster that occurred in 2011.
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Sorption-Reagent Method in Liquid Radioactive Waste Management
MRS Proceedings, 2002Co-Authors: Valentin Avramenko, Dmitry Marinin, V. V. Zheleznov, Elena V. Kaplun, T. A. Sokol’nitskaya, And Anna A. YukhkamAbstract:Methods of Liquid Radioactive Waste (LRW) decontamination from radionuclides including their co-precipitation at specific conditions or adsorption on selective sorption materials are well known and extensively used in LRW management technologies. At the same time, it was shown in a number of papers that some forms of organic and inorganic ionexchangers react with solutions containing specific components that results in formation of virtually insoluble precipitates inside the sorbent matrix or on its surface. Here in some cases the sorbent selectivity to some radionuclides increases substantially. The sorption-reagent materials synthesized for decontamination purposes are the most highly selective in regard to such difficult to remove radionuclides as strontium-90 and cobalt-60. It was shown by comparative analysis of radionuclide removal efficiency by traditional selective sorbents and developed sorption-reagent materials that the latter have the highest distribution coefficients in systems too complex for “pure” sorption/ion-exchange decontamination. For example, the sorption-reagent materials have strontium distribution coefficients several dozens higher than those of commercially available sodium titanates and silicotitanates. The mechanism of radionuclide sorption on sorption-reagent materials of different types was studied. It was shown that this is a multi-stage process and the course of different stages of chemical reactions and sorption is determined by the parameters of medium from which radionuclides are sorbed. It was also shown that these materials application in Liquid Radioactive Waste management enables one to develop simple technological setups combining the advantages of sorption and precipitation methods. One of the main fields of the sorption-reagent materials application can be decontamination of high-salinity Radioactive Waste formed whether as a result of ionexchanger filters regeneration in LRW management systems or in reverse osmosis installations. Use of sorption-reagent materials for high-salinity Waste management enables one to reduce several ten-fold or even hundred-fold the volume of solid Radioactive Waste (SRW) to be sent for final disposal and, therefore, to decrease the cost of LRW management. The approach consisting in combined application of reverse-osmosis and sorption-reagent methods for LRW decontamination is suggested.
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New sorbents and technologies for Liquid Radioactive Waste management
MRS Proceedings, 1996Co-Authors: Dmitry Marinin, Valentin Avramenko, V. I. Sergienko, V. Yu Glushchenko, V. A. Vasilevskiy, V. V. ZheleznovAbstract:The possibilities for using various technologies for Liquid Radioactive Waste (LRW) management were considered. Technologies based on the application of sorbents highly selective to radionuclides were shown to have good prospects. Possible ways of increasing selective sorbent efficiency in cleaning radionuclide-polluted waters of various types were examined. The results of studying new high-selective sorbents produced in the Institute of Chemistry FEDRAS are given. The use of these sorbents enables one to treat LRW of various types in a single stage. The results of testing a sorption filter installation for management of LRW produced during operation, repair and disposal of nuclear reactors are presented. Use of this installation resolves a major portion of LRW disposal problems.
Yu. G. Mokrov - One of the best experts on this subject based on the ideXlab platform.
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Analysis of reconstruction of the composition of Liquid Radioactive Waste released into the Techa River in 1949-1956
International Journal of Low Radiation, 2007Co-Authors: Yu. G. MokrovAbstract:An analysis of archival data of Liquid Radioactive Waste samples and Techa River bottom sediments was made, taking into consideration the radiochemical methods for extraction and beta-emitting radionuclide activity measurements existing in the early 1950s. It was stated that the radionuclide composition of the routine and accidental Liquid Radioactive Waste releases in 19491951 corresponded to the radionuclide composition of the fission products accumulated in the nuclear reactor fuel and in the Liquid Radioactive Waste storage tank, with operating modes typical for that time period in reactor and radiochemical plants. It was stated that the data obtained by Ilyin (1956) for the assessment of radionuclide composition and Liquid Radioactive-Waste release rate in the Techa River were not correct, and for retrospective assessment of the population exposure dose for near-stream residents, this could result in substantial underassessment of the data obtained.
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reconstruction of the radionuclide spectrum of Liquid Radioactive Waste released into the techa river in 1949 1951
Radiation and Environmental Biophysics, 2003Co-Authors: Yu. G. MokrovAbstract:The major part of the Liquid Radioactive Waste released by the Mayak Production Association (PA) radiochemical plant into the Techa river occurred in 1949–1951, but there is information on only one single radiochemical analysis of a water sample taken on 24 and 25 September 1951. These data are here used to assess the spectrum of radionuclides that were released between 1949 and 1951. For this purpose, details of the radiochemical methods of radionuclide extraction and radiometric measurements of β-activity used at Mayak PA in the 1950s have been taken into account. It is concluded that the data from the radiochemical measurements agree with the theoretical composition of fission products in uranium after exposure times in the reactor (120 days) and subsequent hold times (35 days) that were typical for the procedures at that time. The results of the analysis are at variance with assumptions that underlie the current Techa river dosimetry system. They confirm the conclusion that the external doses to the Techa river residents in the critical period up to 1952 were predominantly due to short-lived fission products.
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Reconstruction of the radionuclide spectrum of Liquid Radioactive Waste released into the Techa river in 1949–1951
Radiation and Environmental Biophysics, 2003Co-Authors: Yu. G. MokrovAbstract:The major part of the Liquid Radioactive Waste released by the Mayak Production Association (PA) radiochemical plant into the Techa river occurred in 1949–1951, but there is information on only one single radiochemical analysis of a water sample taken on 24 and 25 September 1951. These data are here used to assess the spectrum of radionuclides that were released between 1949 and 1951. For this purpose, details of the radiochemical methods of radionuclide extraction and radiometric measurements of β-activity used at Mayak PA in the 1950s have been taken into account. It is concluded that the data from the radiochemical measurements agree with the theoretical composition of fission products in uranium after exposure times in the reactor (120 days) and subsequent hold times (35 days) that were typical for the procedures at that time. The results of the analysis are at variance with assumptions that underlie the current Techa river dosimetry system. They confirm the conclusion that the external doses to the Techa river residents in the critical period up to 1952 were predominantly due to short-lived fission products.