Popov L.,Kozloduy NPP
Applied Radiation and Isotopes | Year: 2016
Method for determination of uranium isotopes in various environmental samples is presented. The major advantages of the method are the low cost of the analysis, high radiochemical yields and good decontamination factors from the matrix elements, natural and man-made radionuclides. The separation and purification of uranium is attained by adsorption with strong base anion exchange resin in sulfuric and hydrochloric acid media. Uranium is electrodeposited on a stainless steel disk and measured by alpha spectrometry. The analytical method has been applied for the determination of concentrations of uranium isotopes in mineral, spring and tap waters from Bulgaria. The analytical quality was checked by analyzing reference materials. © 2016 Elsevier Ltd
Agency: European Commission | Branch: FP7 | Program: CSA-CA | Phase: Fission-2011-5.1.1 | Award Amount: 2.24M | Year: 2011
The essence of the project is to provide a special purpose structure for training and qualification of personnel for serving VVER technology as one of nuclear power options used in EU. Such approach should allow unifying existing VVER related training schemes according to IAEA standards and commonly accepted criteria recognized in EU. The structure is based on three general pillars: 1) Training schemes for VVER nuclear professionals; for non-nuclear specialists and subcontractors, involved in nuclear sector; and for students; 2) VVER related knowledge management system, which will accumulate information regarding design data, operational experience, training materials, etc.; and 3) Specialized regional training center for supporting VVER customers with theoretical and practical training sessions, training materials and general and special assignment training tools and facilities. The wider objective of the project is to implement the Council Conclusions of 1 - 2 December 2008 related to skills in the nuclear field: new skills and competences are needed in the context of the Nuclear Renaissance and to fulfill obligations under Article 7 of the COUNCIL DIRECTIVE (EURATOM) establishing a Community; framework for the nuclear safety of nuclear installations. The specific objectives of the project are: - enhancing safety and performance of nuclear installations with VVER technology through specialized initial and continuous training of personnel involved; - keeping the adequate level of safety culture; - contributing to the development of Knowledge Management System for VVER technology; - preserving and further developing nuclear competencies, skills and knowledge related to VVER technology, as a technology used in the EU.
Agency: European Commission | Branch: H2020 | Program: CSA | Phase: NFRP-10-2014 | Award Amount: 2.06M | Year: 2015
The main objective of the proposed CORONA II project is to enhance the safety of nuclear installations through further improvement of the training capabilities aimed at building up the necessary personnel competencies. Specific objective of the proposed CORONA II project is to proceed with the development of state-of-the-art regional training center for VVER competence (which will be called CORONA Academy), whose pilot implementation through CORONA project (2011-2014) proved to be viable solution for supporting transnational mobility and lifelong learning amongst VVER operating countries. The project aims at continuation of the European cooperation and support in the area for preservation and further development of expertise in the nuclear field by improvement of higher education and training. This objective will be realized through networking between universities, research organisations, regulatory bodies, industry and any other organisations involved in the application of nuclear science, ionising radiation and nuclear safety. The proposed CORONA Academy will maintain the nuclear expertise by gathering the existing and generating new knowledge in the VVER area. It will bring together the most experienced trainers in the different aspects of the area within EU and abroad, thus overcoming the mobility challenge that stands ahead the nuclear education and training community. The selected form of the CORONA Academy, together with the online availability of the training opportunities will allow trainees from different locations to access the needed knowledge on demand. The available set of courses will cover the whole range of training of VVER specialists from the university until reaching high professional skills and competences in the area.
Agency: European Commission | Branch: FP7 | Program: CP-IP | Phase: NMP-2007-3.1-3 | Award Amount: 12.50M | Year: 2008
Current practices in risk assessment and management for industrial systems are characterized by its methodical diversity and fragmented approaches. In retrospect these risk and safety paradigms resulted from diverse industries driven and limited by available knowledge and technologies. A change based on industry driven R&D work is needed. At present the European Industry recognised their obligation to reconsider their risk and safety policies, having a more competitive industry and more risk informed and innovation accepting society in vision. Therefore the large collaborative project IRIS is proposed to identify, quantify and mitigate existing and emerging risks to create societal cost-benefits, to increase industrial safety and to reduce impact on human health and environment. The project is led and driven by the industry to consolidate and generate knowledge and technologies which enable the integration of new safety concepts related to technical, human, organizational and cultural aspects. The partnership represents over 1 million workers. The proposed project relates to strategic research topics defined by ETPIS and ECTP and is underpinning relevant EU policies on industrial safety.
Groudev P.,Bulgarian Academy of Science |
Stefanova A.,Bulgarian Academy of Science |
Manolov M.,Kozloduy NPP
Nuclear Engineering and Design | Year: 2013
This paper presents the thermal-hydraulic investigation of spent fuel behavior during its transferring from reactor vessel through refueling cavity (RC) to spent fuel pool (SFP) in case of dry out for VVER440/V230 units 3 and 4 at Kozloduy NPP. The fuel transfer canal connects the refueling cavity and spent fuel pool and this way set up a command pool. The presented analysis has been performed up to the moment of fuel heat up in case of spent fuel pool (SFP) dry out during the first stage of refueling activities. The main feature during this stage is: the maximum decay power of "new" spent fuel; the "new" spent fuel is still in the reactor vessel; the fuel transfer canal connects the refueling cavity and spent fuel pool. In this way the coolant have maximum volume and the spent fuel with maximum decay power is still in the reactor vessel. The "old" spent fuel in SFP has significantly low decay power. The main purpose of this analysis is to estimate the time for dry out of SFP, heat up of spent fuel and time for recovery actions from the operators. In the performed analysis are defined the following stages during the accident.Termination of natural circulation after decreasing of water level in reactor vessel below the hot nozzles.Beginning of coolant heat up in the reactor core.Reaching the temperature of saturation at the outlet of the assembly.Startup of the reactor core uncover.Loss of critical safety functions. The analysis has been performed with the thermal-hydraulic computer code RELAP5/MOD3.2. The RELAP5/MOD3.2 model for Kozloduy NPP VVER-440 have been developed and validated at the Institute for Nuclear Research and Nuclear Energy - Bulgarian Academy of Sciences (INRNE-BAS) Sofia. © 2013 Elsevier B.V.
Popov L.,Kozloduy NPP
Journal of Radioanalytical and Nuclear Chemistry | Year: 2016
An alternative method for determination of Pu isotopes in various environmental samples has been developed. The separation of Pu is attained by two stage solvent extraction with triisooctylamine/xylene in hydrochloric acid and nitric acid [Pu is converted to Pu4+ by the redox system Fe3+/(NO3)−/(SO3)2−] media. The analytical method has been successfully applied for the determination of Pu isotopes in surface air in a 100 km area around the Kozloduy Nuclear Power Plant in Bulgaria and in surface water of the Danube River. The analytical quality was checked by analyzing reference materials from IAEA (Soil-6, IAEA-375, IAEA-384) and NPL (AL-2008, AL-2009, AL-2010, AL-2011). © 2016 Akadémiai Kiadó, Budapest, Hungary
Popov L.,Kozloduy NPP
Journal of Radioanalytical and Nuclear Chemistry | Year: 2013
Novel and robust method for determination of uranium isotopes in various environmental materials is presented. The method is based on total decomposition of the solid materials by the use of closed vessels microwave acid digestion systems and pre concentration of uranium from the liquid samples. The separation of uranium from interfering radionuclides and stable matrix elements is attained by liquid-liquid extraction with triisooctylamine/xylene in sulfuric and consecutively in hydrochloric acid media. Purified uranium is electrodeposited on a stainless steel disks and then measured by alpha spectrometry. The critical steps in the method were examined. The analytical method has been successfully applied to the determination of uranium isotopes in mineral and tap waters, as well as in soils from Northwestern Bulgaria. The analytical quality was checked by analyzing reference materials with different matrices. © 2013 Akadémiai Kiadó, Budapest, Hungary.
Popov L.,Kozloduy NPP
Journal of Radioanalytical and Nuclear Chemistry | Year: 2012
Methods for routine assessment of 3H and 14C content in gaseous releases from ventilation stacks of Kozloduy Nuclear Power Plant (Bulgaria) were developed. Technique for correction of incomplete desorption of tritium from exposed silica gel was proposed. The distribution and the concentrations of both nuclides in various chemical forms were constantly monitored for a period of 1 year. The results for annual normalized gaseous discharges were assessed for the fifth unit at 173 GBq/(GW.a)for 3H and 369 GBq/(GW.a) for 14C, while for the sixth unit - 3H -98 GBq/(GW.a) and 14C -289 GBq/(GW.a). © 2012 Akadémiai Kiadó, Budapest, Hungary.
Popov L.,Kozloduy NPP
Applied Radiation and Isotopes | Year: 2012
Alternative method for determination of uranium isotopes in various environmental samples is presented. The method is based on total decomposition of the solid materials and preconcentration of liquid samples. The separation of uranium from interfering radionuclides and stable matrix elements is attained by liquid-liquid extraction with triisooctylamine/xylene in hydrochloric media. After the additional removal of stable iron by extraction with diisopropyl ether, purified uranium is electrodeposited on stainless steel disks and measured by alpha spectrometry. The analytical method has been successfully applied to the determination of uranium isotopes in water and bottom sediments from the rivers Danube, Ogosta and Tzibritza in Northwestern Bulgaria. The analytical quality was checked by analyzing reference materials with different matrices. © 2012 Elsevier Ltd.
Kozloduy NPP and ATP Atomtoploproekt Ood | Date: 2015-03-25
This invention concerns passive plugging assemblies for prevention of melt outflow on the event of early by-pass of the containment in case of severe accident in a nuclear power plant. The vertical plugging assembly consists of a pipe (1) standing on and fixed to a steel plate (2) and a pipe (3) installed in a concrete structure (4.b). In the pipe (1) there is a plug made of two segments (7.1 and 7.2), fixed to each other by clamps (12.1 and 12.2) and a bioprotection cylinder consisting of two segments (5.1 and 5.2) with a groove (6) and a cable/rope (8). Between pipe (1) and pipe (3) a concrete structure is inlaid. In the segments of the plug there are cavities (10.1 and 10.2) and also a sphere (11), fixed by the cable/rope (8). The horizontal plugging assembly consists of a pipe (14) in a pipe (13) with a horizontal inclination of of 6 to 30 degree in a concrete structure (4.x). Rings (15 and 23) welded to the corpus (14), block the conical saddle (16), with a front (17). Between ring (15) and pressure plate (18), with screw and nut (28), there is a spring (19). The closing conical element (20.3) has two cones (20.1 and 20.2). Two connecting rods (21 and 24) are attached to the element by means of the eyes of two retainer screws (25.1 and 25.2), which are screwed in bushings (26.1 and 26.2) respectively. A connecting rod (24) is attached to an element (22), fixed to the pipe (corpus) (14).