Methodology and measures for preventing unacceptable flow-accelerated corrosion thinning of pipelines and equipment of NPP power generating units

Science.gov (United States)

Tomarov, G. V.; Shipkov, A. A.; Lovchev, V. N.; Gutsev, D. F.

2016-10-01

Problems of metal flow-accelerated corrosion (FAC) in the pipelines and equipment of the condensate- feeding and wet-steam paths of NPP power-generating units (PGU) are examined. Goals, objectives, and main principles of the methodology for the implementation of an integrated program of AO Concern Rosenergoatom for the prevention of unacceptable FAC thinning and for increasing operational flow-accelerated corrosion resistance of NPP EaP are worded (further the Program). A role is determined and potentialities are shown for the use of Russian software packages in the evaluation and prediction of FAC rate upon solving practical problems for the timely detection of unacceptable FAC thinning in the elements of pipelines and equipment (EaP) of the secondary circuit of NPP PGU. Information is given concerning the structure, properties, and functions of the software systems for plant personnel support in the monitoring and planning of the inservice inspection of FAC thinning elements of pipelines and equipment of the secondary circuit of NPP PGUs, which are created and implemented at some Russian NPPs equipped with VVER-1000, VVER-440, and BN-600 reactors. It is noted that one of the most important practical results of software packages for supporting NPP personnel concerning the issue of flow-accelerated corrosion consists in revealing elements under a hazard of intense local FAC thinning. Examples are given for successful practice at some Russian NPP concerning the use of software systems for supporting the personnel in early detection of secondary-circuit pipeline elements with FAC thinning close to an unacceptable level. Intermediate results of working on the Program are presented and new tasks set in 2012 as a part of the updated program are denoted. The prospects of the developed methods and tools in the scope of the Program measures at the stages of design and construction of NPP PGU are discussed. The main directions of the work on solving the problems of flow

Simulation spread sheet of Angra-1 secondary circuit

International Nuclear Information System (INIS)

Futuro, F.L.; Rucos, J.; Ogando, A.; Maprelian, E.; Bassel, W.S.; Baptista Filho, B.D.

2000-01-01

The efficient operation of a Nuclear Power Plant (NPP) requires the continuous identification of derivations in the main operating parameters. The identification and analysis of those derivations allow someone to detect the degradation of instruments or even of any equipment. In order to study this problem the group of thermal generation of Angra 1 NPP, devised the use of a Microsoft Excel spread sheet for the automation of Angra 1 thermal balance. In the set of simulation spread sheets, measured values of the secondary system main parameters were compared with project values for a given reactor power level and condenser pressure. The spread sheets provide the turbines power and efficiency and do the plant thermal balance. This work presents a general description of the spread sheets set and a real case analysis of Angra 1 NPP, showing its precision and use easiness. (author)

Modelling of preheated regenerative chain in Cernavoda NPP using MMS calculation code

International Nuclear Information System (INIS)

Bigu, M.; Nita, I.; Prisecaru, I.; Dupleac, D.

2005-01-01

Full text: In this work it was studied operation of preheated regenerative chain from NPP Cernavoda. To obtain this analysis coupled analyses of condensate system, water supply system, and drain cooler system were effected. The analysis boundaries are: Upstream: - Steam condensers - Turbine Bleed Steam Downstream: - Steam Generators. The analysis was made in two steps: 1) Getting of hydraulic characteristic of pipe network from steam condensers to steam generators at nominal regime; this step was obtained with hydraulic package called PIPENET. 2) Real thermal hydraulic analyses were done based on hydraulic characteristic of pipe network and supplementary data required for heat transfer calculation in equipment of preheated regenerative chain. Thermal analyses were done using MMS package and refered to normal operating regimes, namely, nominal operating regime required for calibration of calculating model, shutdown regime, start-up regime from zero power hot to nominal power and to abnormal operating regimes, namely, turbine trip, reactor trip and loss of two condensate pumps. The results were compared with already existing analysis and showed the largest differences at interface areas (i.e. 5%). This led us to idea of extending analysis to all secondary circuits in order to reduce the number of boundary conditions which can generate uncertainty in analysis. In this analysis we obtained an advanced model of preheated regenerative chain of secondary circuit in Cernavoda NPP which could be extended up to cover the whole secondary circuit by including the analysis of steam generators, turbine, and steam condenser. (authors)

Modelling of preheated regenerative chain in Cernavoda NPP using MMS calculation code

International Nuclear Information System (INIS)

Bigu, M.; Nita, I.; Prisecaru, I.; Dupleac, D.

2005-01-01

In this work it was studied operation of preheated regenerative chain from NPP Cernavoda. To obtain this analysis coupled analyses of condensate system, water supply system, and drain cooler system were effected. The analysis boundaries are: Upstream: - Steam condensers - Turbine Bleed Steam Downstream: - Steam Generators. The analysis was made in two steps: 1) Getting of hydraulic characteristic of pipe network from steam condensers to steam generators at nominal regime; this step was obtained with hydraulic package called PIPENET. 2) Real thermal hydraulic analyses were done based on hydraulic characteristic of pipe network and supplementary data required for heat transfer calculation in equipment of preheated regenerative chain. Thermal analyses were done using MMS package and referred to normal operating regimes, namely, nominal operating regime required for calibration of calculating model, shutdown regime, start-up regime from zero power hot to nominal power and to abnormal operating regimes, namely, turbine trip, reactor trip and loss of two condensate pumps. The results were compared with already existing analysis and showed the largest differences at interface areas (i.e. 5%). This led US to idea of extending analysis to all secondary circuits in order to reduce the number of boundary conditions which can generate uncertainty in analysis. In this analysis we obtained an advanced model of preheated regenerative chain of secondary circuit in Cernavoda NPP which could be extended up to cover the whole secondary circuit by including the analysis of steam generators, turbine, and steam condenser. (authors)

Q-factor of coolant flow in the primary circuit of NPP with pressurised water reactors

International Nuclear Information System (INIS)

Proskuryakov, K.N.; Belikov, S.O.; Novikov, K.S.

2011-01-01

Systems of preoperational vibration dynamic monitoring in of WWER are presented. The results of measurements during commission of NPP with WWER are presented. The paper provides the result of the research, that estimation of coolant fluctuations caused by pulse perturbation of pressure in the primary circuit NPP. It is shown that results could be received at known value of a Q - factor of acoustical oscillatory system only. The research demonstrates the results of dependence of the sound speed from the mass steam content in the coolant flow thru reactor core. The worked out results can be used for identification of the reasons of abnormal growth of level of vibrations of fuel assembly, fuel rod, equipment and internals, and for forecasting the operation conditions which provide of vibration - acoustical resonances in the primary loop equipment. (author)

33 CFR 183.440 - Secondary circuits of ignition systems.

Science.gov (United States)

2010-07-01

... systems. 183.440 Section 183.440 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Electrical Systems Manufacturer Requirements § 183.440 Secondary circuits of ignition systems. (a) Each conductor in a secondary circuit of an...

Secondary Circuit Start Up Chemistry Optimisation

International Nuclear Information System (INIS)

Fontan, Guillaume; Morel, Pascal

2012-09-01

In a context of investment and renewal of equipment, Electricite De France (EDF) put enhanced efforts on operating practices during start-up of the secondary circuit, in order to improve operational performance and materials lifetime. This article focuses on the objective of optimizing the filling, the chemical conditioning and the thermal conditioning of the secondary fluid, while taking into account the following issues: - Limiting the time required to obtain a proper chemistry, - Limiting the amount of water and steam used, - Limiting the amount of effluent generated. The scope is all start-up conditions of secondary circuit, both after refuelling outage or fortuitous shutdowns of the plant. The recommendations produced are based on existing local procedures and good practices, which were collected and developed in order to propose a generic methodology understandable and useful both for operators, chemists and managers. (authors)

Secondary School Students' Misconceptions about Simple Electric Circuits

Science.gov (United States)

Küçüközer, Hüseyin; Kocakülah, Sabri

2007-01-01

The aim of this study is to reveal secondary school students' misconceptions about simple electric circuits and to define whether specific misconceptions peculiar to Turkish students exist within those identified. Data were obtained with a conceptual understanding test for simple electric circuits and semi-structured interviews. Conceptual…

A study on prediction of metal loss by flow-accelerated corrosion in the CANDU NPP secondary piping systems

International Nuclear Information System (INIS)

Shim, S. H.; Song, J. S.; Yoon, K. B.; Hwang, K. M.; Jin, T. E.; Lee, S. H.; Kim, W. S.

2001-01-01

Flow-Accelerated Corrosion(FAC) is a phenomenon that results in metal loss from piping, vessels, and equipment made of carbon steel. FAC occurs only under certain conditions of flow, chemistry, geometry, and material. Unfortunately, those conditions are in much of the high-energy piping in nuclear and fossil-fueled power plants. Also, for domestic NPP secondary pipings whose operating time become longer, more evidences of FAC have been reported. The authors are studying on FAC management using CHECWORKS, computer code developed by EPRI. This paper is on the prediction results of metal loss by FAC in the one of CANDU type NPP secondary piping systems

Method for heating of the primary circuit of WWER electric power units at cold start-up

International Nuclear Information System (INIS)

Ivanov, I.N.; Dimitrov, B.D.; Korkinova, M.I.

1982-01-01

The method increases the heating rate and shorten the start-up time of the electric power units. It comprises a primary stopping of the reactor core heating and provides a forced circulation of the heat-carrier through the circulation cycles of the primary circuit. The thermal energy is supplied in one or several steam generators in the secondary circuit of an NPP operating unit. 1 cl., 3 figs

Status of steam generator tubing integrity at Jaslovske Bohunice NPP

International Nuclear Information System (INIS)

Cepcek, S.

1997-01-01

Steam generator represents one of the most important component of nuclear power plants. Especially, loss of tubing integrity of steam generators can lead to the primary coolant leak to secondary circuit and in worse cases to the unit shut down or to the PTS events occurrence. Therefore, to ensure the steam generator tubing integrity and the current knowledge about tube degradation propagation and development is of the highest importance. In this paper the present status of steam generator tubing integrity in operated NPP in Slovak Republic is presented

Application of Moessbauer spectroscopy on corrosion products of NPP

Energy Technology Data Exchange (ETDEWEB)

Dekan, J., E-mail: julius.dekan@stuba.sk; Lipka, J.; Slugen, V. [Institute of Nuclear and Physical Engineering, Faculty of Electrical Engineering and Information Technology, SUT (Slovakia)

2013-04-15

Steam generator (SG) is generally one of the most important components at all nuclear power plants (NPP) with close impact to safe and long-term operation. Material degradation and corrosion/erosion processes are serious risks for long-term reliable operation. Steam generators of four VVER-440 units at nuclear power plants V-1 and V-2 in Jaslovske Bohunice (Slovakia) were gradually changed by new original 'Bohunice' design in period 1994-1998, in order to improve corrosion resistance of SGs. Corrosion processes before and after these design and material changes in Bohunice secondary circuit were studied using Moessbauer spectroscopy during last 25 years. Innovations in the feed water pipeline design as well as material composition improvements were evaluated positively. Moessbauer spectroscopy studies of phase composition of corrosion products were performed on real specimens scrapped from water pipelines or in form of filters deposits. Newest results in our long-term corrosion study confirm good operational experiences and suitable chemical regimes (reduction environment) which results mostly in creation of magnetite (on the level 70 % or higher) and small portions of hematite, goethite or hydrooxides. Regular observation of corrosion/erosion processes is essential for keeping NPP operation on high safety level. The output from performed material analyses influences the optimisation of operating chemical regimes and it can be used in optimisation of regimes at decontamination and passivation of pipelines or secondary circuit components. It can be concluded that a longer passivation time leads more to magnetite fraction in the corrosion products composition.

New approach of second Romanian NPP siting

International Nuclear Information System (INIS)

Mauna, Traian

2010-01-01

The NPP sitting studies in Romania began before 1975. The first Romanian NPP CANDU 6 type reactor gone to erection in 1980 on Cernavoda site planned to have 5 units. Gained the experience from Cernavoda NPP sitting, the first mission of new multi-branch of specialists team was to choose new NPP sites adapting the NPP Cernavoda project to the new parameters of close water cooling circuit and hard less and no rock foundation strata. The studies were carrying out in different stages on the inner rivers Olt, Mures, Somes in Transylvania historical region. This paper tries to reconsider shortly the old analysis according to the last IAEA Safety Standards, taking into account the new NPP generation requirement. Paper is focused on geological aspects and other local sites characteristics. (authors)

NPP capital equipment life control facilities and tools

International Nuclear Information System (INIS)

Nekrasov, A.V.; Proskuryakov, K.N.

2009-01-01

Algorithms and simulation package for calculation of eigen modes of coolant pressure oscillations in equipment of primary coolant circuit of WWER-1000 NPP, tuned-circuit Q-factor of an oscillating contour of the coolant, fluctuation frequencies pass band and attenuation factors of were developed. Calculation results for cases of presence and absence of gaseous state radiolysis products in the coolant were obtained. Results analysis makes it possible to disclose operating conditions which result in raised vibrations, and to develop control response in NPP industrial control system for their prevention [ru

Engine Tune-Up Service. Unit 4: Secondary Circuit. Posttests. Automotive Mechanics Curriculum.

Science.gov (United States)

Morse, David T.

This book of posttests is designed to accompany the Engine Tune-Up Service Student Guide for Unit 4, Secondary Circuit, available separately as CE 031 214. Focus of the posttests is testing and servicing the secondary ignition circuit. One multiple choice posttest is provided that covers the seven performance objectives contained in the unit. (No…

Feeding and purge systems of coolant primary circuit and coolant secondary circuit control of the I sup(123) target

International Nuclear Information System (INIS)

Almeida, G.L. de.

1986-01-01

The Radiation Protection Service of IEN (Brazilian-CNEN) detected three faults in sup(123)I target cooling system during operation process for producing sup(123)I: a) non hermetic vessel containing contaminated water from primary coolant circuit; possibility of increasing radioactivity in the vessel due to accumulation of contaminators in cooling water and; situation in region used for personnels to arrange and adjust equipments in nuclear physics area, to carried out maintenance of cyclotron and target coupling in irradiation room. The primary circuit was changed by secondary circuit for target coolant circulating through coil of tank, which receive weater from secondary circuit. This solution solved the three problems simultaneously. (M.C.K.)

Nuclear Power Plants Secondary Circuit Piping Wall-Thinning Management in China

International Nuclear Information System (INIS)

Zhong Zhimin; Li Jinsong; Zheng Hui

2012-01-01

Research and field feedbacks showed that nuclear power plants secondary circuit steam and water piping are more sensitive than that of fuel plant to the attack of flow-accelerated corrosion (FAC). FAC, Liquid droplet impingement or cavitation erosion will cause secondary circuit piping local wall-thinning in NPPs. Without effective management, the wall-thinning in those high energy piping will cause leakage or pipe rupture during nuclear power plant operation, more seriously cause unplanned shut down, injured and fatality, or heavy economic losses. This paper briefly introduces the history, development and state of the art of secondary circuit piping wall-thinning management in China NPPs. Then, the effectiveness of inspection grid size selecting was analyzed in detail based on field feedbacks. EPRI recommendatory inspection grid, JSME code recommendatory grid and plant specific inspection grid were compared and the detection probabilities of local wall-thinning were estimated. Then, the development and application of NPPs Secondary Circuit Piping Wall Thickness Management Information System, developed, operated and maintained by our team, was briefly introduced and the statistical analysis results of 11 PWR units were shared. It was conclude that the long term, systemic, effective wall-thinning management strategy of high energy piping was very important to the safety and economic operation of NPPs. Furthermore, take into account the actual situation of China nuclear power plants, some advice and suggestion on developing effective nuclear power plant secondary circuit steam and water piping wall-thinning management system are put forward from code development, design and manufacture, operation management, pipeline and locations selection, inspection method selection and application, thickness measurement result evaluation, residual life predication and decision making, feedbacks usage, personnel training and etc. (author)

Sitting Safety Aspects of Second Romanian NPP

International Nuclear Information System (INIS)

Mauna, T.

2010-01-01

The first Romanian NPP CANDU 6 type reactor gone to erection in 1980 on Cernavoda site planned to have 5 units like the Wolsong applied design project for nuclear island. For the BOP parts the ASALDO-GE project was applied with the careful about the interface connection NSP requirements. The new NPP sitting studies began from 1982 in a serious manner as first part on Nuclear Power Plant Romanian Program adopted by political and governmental authorities at the time. For develop the all package of the studies in concordance with the first IAEA Safety Standards recommendations. Till the 1982 the first mission of design and research multi-branch of specialists team was to adapt the NPP Cernavoda project having a open water cooling circuit to the new parameters of close water cooling circuit. But the team was looking at the other type of NPP for sitting. Also in the same time was studied the possibility of NSP foundation on hard less or soft soil foundation strata in connection with safety aspects. The close circuit of cooling water means others parameters of systems and need very large cooling towers. Also must be reconsidering the safety systems design and performance as new solution. In the south of Transylvania historical region in Romania the Olt River run from west to east having medium multi annual flow around 70 m3/s. The Olt River has a chain of small hydropower in operation and other planned. From geological and geophysical points of view two main faults, along the Olt river valley, one of this having seismically small activities was detected. Site region geotechnical studies show small quantity underground natural gas, salt and peat. The initial nuclear program has imposed 4 NPP units site near Olt River. Taking into account the orogenesis, water cooling needs and other local feature can't be built more than two NPP units on a site. This paper tries to reconsider the old analysis from the last IAEA Safety Standards point of view taking into account the new

Application of the leak-before-break concept to the primary circuit piping of the Leningrad NPP

Energy Technology Data Exchange (ETDEWEB)

Eperin, A.P.; Zakharzhevsky, Yu.O.; Arzhaev, A.I. [and others

1997-04-01

A two-year Finnish-Russian cooperation program has been initiated in 1995 to demonstrate the applicability of the leak-before-break concept (LBB) to the primary circuit piping of the Leningrad NPP. The program includes J-R curve testing of authentic pipe materials at full operating temperature, screening and computational LBB analyses complying with the USNRC Standard Review Plan 3.6.3, and exchange of LBB-related information with emphasis on NDE. Domestic computer codes are mainly used, and all tests and analyses are independently carried out by each party. The results are believed to apply generally to RBMK type plants of the first generation.

Ignalina NPP Safety Analysis: Models and Results

International Nuclear Information System (INIS)

Uspuras, E.

1999-01-01

Research directions, linked to safety assessment of the Ignalina NPP, of the scientific safety analysis group are presented: Thermal-hydraulic analysis of accidents and operational transients; Thermal-hydraulic assessment of Ignalina NPP Accident Localization System and other compartments; Structural analysis of plant components, piping and other parts of Main Circulation Circuit; Assessment of RBMK-1500 reactor core and other. Models and main works carried out last year are described. (author)

Engine Tune-Up Service. Unit 4: Secondary Circuit. Student Guide. Automotive Mechanics Curriculum.

Science.gov (United States)

Bacon, E. Miles

This student guide is for Unit 4, Secondary Circuit, in the Engine Tune-Up Service portion of the Automotive Mechanics Curriculum. It deals with how to test and service the secondary ignition circuit. A companion review exercise book and posttests are available separately as CE 031 215-216. An introduction tells how this unit fits into the total…

Engine Tune-up Service. Unit 4: Secondary Circuit. Review Exercise Book. Automotive Mechanics Curriculum.

Science.gov (United States)

Bacon, E. Miles

This book of pretests and review exercises is designed to accompany the Engine Tune-Up Service Student Guide for Unit 4, Secondary Circuit, available separately as CE 031 214. Focus of the exercises and pretests is testing and servicing the secondary ignition circuit. Pretests and performance checklists are provided for each of the seven…

Operation results of the secondary circuits of the French PWR type power plant park

International Nuclear Information System (INIS)

Mercier, J.P.

1984-01-01

Global results of performances realized since 1981 by the French PWR 900 MW power plants (installed power, availability, casual or planned shutdowns); analysis of the behaviour (casual unavailability) comparing together the performances of the different components in the secondary circuit; behaviour of the principal materials of the secondary circuit and their weight in the unavailabilities of the whole French nuclear park [fr

Modifications in secondary circuit chemistry of Atucha I nuclear power plant

International Nuclear Information System (INIS)

Iglesias, Alberto M.; Jimenez Rebagliatti, Raul; Gentilli, Nelida; Raffo Calderon, Maria C.; Gemini, Hector

1999-01-01

The CNA I secondary circuit presents, by design, some materials which are difficult to be compatible from the corrosion point of view. The presence of Cu alloys limits the use of ammonia (or products that for decomposition generates it) as pH regulator substance which would be convenient to minimize the corrosion processes. The pH limit value in agreement with the operative experience is 9.2. This value is below the one required to minimize the effects of corrosion on the carbon steel, which is present inside the secondary circuit with a considerable exposed area and under hydrodynamic and hydrothermal conditions that favor those processes. This corrosive effect diminishes below certain limits, i. d. if the pH value is increased. The realization of this study involves three stages at least: a)- Independent measurements and description of the circuit current state; b)- Laboratory experiences of the possible alternatives into replace NH3 as alkaline agent and to provide better control of the corrosion process, on Cu alloys as well as steel alloys; c)- Plant implementations of the actions that are feasible from the point of view of power station operation, in such a way that in the secondary circuit it minimizes the presence of ammonia in the vapor phase and at the same time, the possibility of increasing the pH of the liquid phase, to diminish the corrosion phenomena of carbon steel. (author)

Chernobyl NPP decommissioning efforts - Past, Present and Future. Decommissioning Efforts on Chernobyl NPP site - Past, Present

International Nuclear Information System (INIS)

Kuchinskiy, V.

2017-01-01

Two unique large-scale projects are underway at the moment within the Chernobyl - Exclusion zone - Shelter object transformation into ecologically safe system and the decommissioning of 3 Chernobyl NPP Units. As a result of beyond design accident in 1986 the entire territory of the industrial site and facilities located on it was heavily contaminated. Priority measures were carried out at the damaged Unit under very difficult conditions to reduce the accident consequences and works to ensure nuclear and radiation safety are continuous, and the Unit four in 1986 was transformed into the Shelter object. Currently, works at the Shelter object are in progress. Under assistance of the International Community new protective construction was built above the existing Shelter object - New Safe Confinement, which will ensure the SO Safety for the long term - within up to 100 years. The second major project is the simultaneous decommissioning of Chernobyl NPP Units 1, 2 and 3. Currently existing Chernobyl NPP decommissioning Strategy has been continuously improved starting from the Concept of 1992. Over the years the following was analyzed and taken into account: the results of numerous research and development works, international experience in decommissioning, IAEA recommendations, comments and suggestions from the governmental and regulatory bodies in the fields of nuclear energy use and radioactive waste management. In 2008 the final decommissioning strategy option for Chernobyl NPP was approved, that was deferred gradual dismantling (SAFSTOR). In accordance with this strategy, decommissioning will be carried out in 3 stages (Final Shutdown and Preservation, Safe Enclosure, Dismantling). The SAFSTOR strategy stipulates: -) the preservation of the reactor, the primary circuit and the reactor compartment equipment; -) the dismantling of the equipment external in relation to the reactor; -) the safe enclosure (under the supervision); -) the gradual dismantling of the primary

Intelligent system for accident identification in NPP

International Nuclear Information System (INIS)

Hernandez, J.L.

1998-01-01

Accidental situations in NPP are great concern for operators, the facility, regulatory bodies and the environmental. This work proposes a design of intelligent system aimed to assist the operator in the process of decision making initiator events with higher relative contribution to the reactor core damage occur. The intelligent System uses the results of the pre-operational Probabilistic safety Assessment and the Thermal hydraulic Safety Analysis of the NPP Juragua as source for building its knowledge base. The nucleus of the system is presented as a design of an intelligent hybrid from the combination of the artificial intelligence techniques fuzzy logic and artificial neural networks. The system works with variables from the process of the first circuit, second circuit and the containment and it is presented as a model for the integration of safety analyses in the process of decision making by the operator when tackling with accidental situations

NPPs Secondary Circuit Piping Wall-Thinning Management in China

International Nuclear Information System (INIS)

Zhong Zhimin; Li Jinsong; Zheng Hui

2012-01-01

Since 1980s, secondary circuit piping wall-thinning incidents happened in nuclear power plants (NPPs) worldwide. Particularly Surry 2 and Mihama 3 accidents resulted from flow-accelerated corrosion (FAC), unplanned outage, huge fatalities and economic loss pushed whole industry to pay more attention on the wall-thinning problem.

Corrosion behaviour of dissimilar welds between martensitic stainless steel and carbon steel from secondary circuit of candu npp

International Nuclear Information System (INIS)

Popa, L.; Fulger, M.; Tunaru, M.; Velciu, L.; Lazar, M.

2015-01-01

Corrosion damages of welds occur in spite of the fact that the proper base metal and filler metal have been correctly selected, industry codes and standards have been followed and welds have been realized with full weld penetration and have proper shape and contour. It is not unusual to find that, although the base metal or alloy is resistant to corrosion in a particular environment, the welded counterpart is not resistant. In secondary circuit of a Nuclear Power Station there are some components which have dissimilar welds. Our experiments were performed in chloride environmental on two types of samples: non-welded (420 martensitic steel and 52.2k carbon steel) and dissimilar welds (dissimilar metal welds: joints beetween 420 martensitic steel and 52.2k carbon steel). To evaluate corrosion susceptibility of dissimilar welds was used electrochemical method (potentiodynamic method) and metallography microscopy (microstructural analysis). The present paper follows the localized corrosion behaviour of dissimilar welds between austenitic stainless steel and carbon steel in solutions containing chloride ions. We have been evaluated the corrosion rates of samples (welded and non-welded) by electrochemically. (authors)

Detection of primary coolant leaks in NPP

International Nuclear Information System (INIS)

Slavov, S.; Bakalov, I.; Vassilev, H.

2001-01-01

The thermo-hydraulic analyses of the SG box behaviour of Kozloduy NPP units 3 and 4 in case of small primary circuit leaks and during normal operation of the existing ventilation systems in order to determine the detectable leakages from the primary circuit by analysing different parameters used for the purposes of 'Leak before break' concept, performed by ENPRO Consult Ltd. are presented. The following methods for leak detection: measurement of relative air humidity in SG box (can be used for detection of leaks with flow rate 3.78 l/min within one hour at ambient parameters - temperature 40 0 - 60 0 C and relative humidity form 30% to 60%); measurement of water level in SG box sumps (can not be used for reliable detection of small primary circuit leakages with flow rate about 3.78 l/min); measurement of gaseous radioactivity in SG box( can be used as a general global indication for detection of small leakages from the primary circuit); measurement of condensate flow after the air coolers of P-1 venting system (can be used for primary circuit leak detection) are considered. For determination of the confinement behaviour, a model used with computer code MELCOR has been developed by ENPRO Consult Ltd. A brief summary based on the capabilities of the different methods of leak detection, from the point of view of the applicability of a particular method is given. For both Units 3 and 4 of Kozloduy NPP a qualified complex system for small leak detection is planned to be constructed. Such a system has to unite the following systems: acoustic system for leak detection 'ALUS'; system for control of the tightness of the main primary circuit pipelines by monitoring the local humidity; system for primary circuit leakage detection by measuring condensate run-off in collecting tank after ventilation system P-1 air coolers

Some aspects of correction additions optimisation of water chemistry regime of Kozloduy NPP power units 3 and 4

International Nuclear Information System (INIS)

Topalova, I.

2005-01-01

Optimization of the water-chemistry regime is a major corrective measure for minimization of the corrosion processes of the nuclear power unit equipment. Research done in NPP Kozloduy III - IV power units concerning the migration of the corrosion products in the water of secondary circuit as well as the connection between corrosion processes and fluctuation in parameters of the applied water-chemistry regime are reported. Analysis of the dependences obtained lead to conclusions for optimization of the water chemistry regime of secondary circuit and minimization of the corrosion processes and improvement of corrosion condition of metal surfaces. The research is done for the circuit of each of the 8 turbines of the two power units for a period of 10 days. Data received is quantitatively representative /40-50 points/ for performing of analysis and reaching certain conclusions for the water chemistry regime and development of corrosion processes. Dependence of iron and copper concentration in the work medium on the pH, ammonia and hydrazine concentration as well as the dependence of pH on ammonia concentration in case of different quantity and composition of corrosion products on the different power units' equipment metal surfaces are shown. (author)

Development and Simulation of Increased Generation on a Secondary Circuit of a Microgrid

Science.gov (United States)

Reyes, Karina

As fossil fuels are depleted and their environmental impacts remain, other sources of energy must be considered to generate power. Renewable sources, for example, are emerging to play a major role in this regard. In parallel, electric vehicle (EV) charging is evolving as a major load demand. To meet reliability and resiliency goals demanded by the electricity market, interest in microgrids are growing as a distributed energy resource (DER). In this thesis, the effects of intermittent renewable power generation and random EV charging on secondary microgrid circuits are analyzed in the presence of a controllable battery in order to characterize and better understand the dynamics associated with intermittent power production and random load demands in the context of the microgrid paradigm. For two reasons, a secondary circuit on the University of California, Irvine (UCI) Microgrid serves as the case study. First, the secondary circuit (UC-9) is heavily loaded and an integral component of a highly characterized and metered microgrid. Second, a unique "next-generation" distributed energy resource has been deployed at the end of the circuit that integrates photovoltaic power generation, battery storage, and EV charging. In order to analyze this system and evaluate the impact of the DER on the secondary circuit, a model was developed to provide a real-time load flow analysis. The research develops a power management system applicable to similarly integrated systems. The model is verified by metered data obtained from a network of high resolution electric meters and estimated load data for the buildings that have unknown demand. An increase in voltage is observed when the amount of photovoltaic power generation is increased. To mitigate this effect, a constant power factor is set. Should the real power change dramatically, the reactive power is changed to mitigate voltage fluctuations.

The intelligent system for accident identification in NPP

International Nuclear Information System (INIS)

Hernandez, Jorge Luis.

1998-01-01

Accidental situations in NPP are of greet concern for operators, the facility, regulatory bodies and the environment. This work proposes a design of intelligent system aimed to assist the operator in the process of decision making when initiator events with higher relative contribution to the reactor core damage occur. The intelligent System uses the results of the pre operational Probabilistic Safety Assessment and the Thermal hydraulic Safety Analyses of the NPP Juragua as source for building its knowledge base. The nucleus of the system is presented as a design of an intelligent hybrid system from the combination of the artificial intelligence techniques: fussy logic and artificial neural networks. The system works with variables from the process of the firsts circuit, second circuit and the containment and it is presented as a model for the integration of safety analyses in the process of decision making by the operator when tackling with accidental situations

Unusual occurrences during the whole operation of BN-250 NPP

International Nuclear Information System (INIS)

Andropenkov, S.

2000-01-01

Unusual occurrences during the whole operation BN-350 NPP. 1. Oil ingress in high pressure receiver for the not reveled reason, 12.05.1994. 2. lncrease of water radioactivity of circulating water supply system due to heat exchanger leak of spent fuel assembly washing out system, 17.09.1993. 3. Lack of passableness of sodium drain header of primary circuit reveled during inspection on scheduled preventative maintenance, 28.11.1996. 4. Destruction of the blow-off line of MCP-6 due to corrosion damage of the pipeline while unit was being operated at rated power, 23.04.1993. 5. Lack of passableness of blow-down pipeline connecting reactor gas cover with gas-type pressurizer while unit was being operated at rated power, 17.11.1994. 6. Sodium ingress in blow-down pipeline of loop-5 intermediate heat exchanger while loop-5 was being fed of sodium during scheduled preventative maintenance, 27.06.1994. 7. Resistance deterioration of electro heating zones of loop-4 due to heat exchanger leak and water ingress in air-pipeline of primary circuit boxes recirculating air system, 02.05.1997. 8. Resistance deterioration of electro heating zones of sodium drain header of secondary circuit was sopped in the water for the extinguishing the fire of blowing ventilation oil-strainer, 23.12.1994. 9. Sodium ingress in gas-type pressurizer through pipeline of primary sodium cleanup system and blow-down pipeline of failed MCP-2 while primary sodium cleanup system was being connected to the primary circuit, 17.08.1976. As a rule, the main reactor systems are scrutinized more carefully than the auxiliary reactor systems and the order actions are existed for eliminating and mitigating of consequences of main reactor system fails. Therefore the auxiliary reactor system fails may impact on the main reactor systems through places of its contact in significant measure. The influence of auxiliary reactor system fails on main reactor systems and its possible consequences for behavior of the main

Accidents during shutdown conditions for NPP with WWER-1000/428

International Nuclear Information System (INIS)

Antropov, H.A.

1996-01-01

This paper considers the effect of such internal initiating events upon safety of the NPP with WWER-1000/428 as boron dilution and loss of residual heat removal at the reduced coolant inventory in the primary circuit. 2 refs

New appraisement of siting for a NPP on Mures river

International Nuclear Information System (INIS)

Traian Mauna

2010-01-01

The studies for a second NPP siting on inner Romanian rivers began in a careful manner since 1982 as a first part of the Nuclear Power Plant Romanian Program adopted by political and governmental authorities at the time. The experience gained from Cernavoda NPP siting, the first mission of new multi-branch of specialists team was to choose new NPP sites adapting the CANDU type NPP Cernavoda project to the new parameters of close water cooling circuit and of hard less or no rock foundation strata. The new sites conditions mean a lot of changes of CANDU license and a decrease the output power supplied to the national electric grid. The studies on the Mures river as alternative site of Olt river in Transylvania region began in 1986 and were stopped after 1990. This paper tries to reconsider shortly the old analysis focused on geological and geotechnical aspects and other local sites characteristics according to the last IAEA Safety Standards taking into account also the last types of NPP generations and the number of units. (author)

Radiation protection in decommissioning of the NPP V1

International Nuclear Information System (INIS)

Svitek, J.; Kaizer, J.; Siska, J.

2014-01-01

What's new in decommissioning of the NPP V1? In 2014 the first stage of the decommissioning should be finished. The program of the first stage was characterized by decommissioning of the non-contaminated facilities and buildings (facilities and buildings out of the control area). However, during the first stage, two key activities were done during which radiation protection had to be especially supervised: BIDSF project - Treatment and Conditioning of Wet Historical Waste - Sludge and Sorbents in the operational tanks NPP V1 (the treatment has been the condition of the regulatory body for the ending of the first stage) and preparation of decontamination of both primary circuits NPP (without reactors). In the year 2015, the second stage of decommissioning should be started. Program for the second stage is broad and it includes fragmentation and treatment of activated parts of the primary circuits (reactors, their internal parts, shielding cassettes). Modification of the radiation protection equipment on the NPP site has been made by BIDSF projects. During the first stage, two basic projects have been done: C12 - Refurbishment of the radiation protection monitoring equipment and C-10 - Free release of decommissioning materials. The present state of monitoring systems, as the result of the aforementioned projects, and the first experiences are main part of this presentation. Another activity, which prepared basic conditions for an execution of radiation protection in the second stage of decommissioning, was the preparation of documents for the procurement of license for the second stage of decommissioning. (authors)

Example of an application of systematic approach to training. Paks NPP Ltd

International Nuclear Information System (INIS)

Bajor, L.

1998-01-01

In order to show a practical example of how Hungarian Maintenance program works implementation of SAT based training of primary circuit field operator is described in detail as implemented at Paks NPP

Design safety improvements of Kozloduy NPP

International Nuclear Information System (INIS)

Hinovski, I.

1999-01-01

Design safety improvements of Kozloduy NPP, discussed in detail, are concerned with: primary circuit integrity; reactor pressure vessel integrity; primary coolant piping integrity; primary coolant overpressure protection; leak before break status; design basis accidents and transients; severe accident analysis; improvements of safety and support systems; containment/confinement leak tightness and strength; seismic safety improvements; WWER-1000 control rod insertion; upgrading and modernization of Units 5 and 6; Year 2000 problem

Simulation of the dynamic behaviour of the secondary circuit of a WWER-440 type nuclear power plant Pt. 1

International Nuclear Information System (INIS)

Gacs, A.; Janosy, J.S.; Kiss, Zs.

1987-07-01

This report describes the simulation model of the secondary circuit of a WWER-440 type nuclear power plant. The goal of this modelling is to simulate normal and small abnormal transients in a Basic Principles Simulator. The earlier reports describing the dynamic simulation of primary circuit of a WWER-440 nuclear power plant are KFKI--1983-127 and KFKI--1985-08. At present the controllers of the secondary circuit are not simulated. Finally, some simulation results are presented. (author)

Loose part trapping device in the secondary circuit of a steam generator

International Nuclear Information System (INIS)

Poussin, C.; Ayme, H.

1993-01-01

The trap is principally formed from mesh filter placed across the annular section of the secondary circuit. The maximum mesh size is less than the distance separating the tubes so that the loose parts cannot caught between the tubular bundle tubes. 6 figs

Example of an application of systematic approach to training. Paks NPP Ltd

International Nuclear Information System (INIS)

Szabo, Z.

1998-01-01

In order to show a practical example of how Hungarian Maintenance program works implementation of SAT based training of primary circuit valve maintenance senior mechanic is described and explained in detail as done at Paks NPP

Some questions of optimization in the personnel dosimetry at NPP

International Nuclear Information System (INIS)

Liberman, A.N.; Petrov, V.I.; Bronshtejn, I.Eh.

1978-01-01

Some possible ways of optimizing the radiation monitoring of personnel of nuclear power plants (NPP) are considered. For premises within the zone of a strict operating regime, it is proposed that the intervals between periods of monitoring be shortened if the operating conditions are normal. To improve the monitoring of activity of water in the primary circuit, it is considered desirable to provide all NPP with a system of automatic radiation monitoring having input to the control panel. Where the work involves opening of primary circuit communications or deactivation of equipment and also in cases of emergency, it is proposed that, in addition to routine monitoring, gamma-spectrometric or radiochemical analysis of the isototip composition of contaminants be carried out. Because of the absence of measurable quantities of incorporated radionuclides in the vast majority of those working in the strict regime zone, it is suggested that the number of persons subject to systematic individual monitoring of internal radiation be limited

Automation of the electromagnetic filter applied for condensation water treatment in the secondary cooling system of the Paks Nuclear Power Plant

International Nuclear Information System (INIS)

Szilagyi, Gyoergy

1989-01-01

A full-flow condensation water purification system is applied in the secondary cooling circuit of the Paks NPP. The electromagnetic filter of the filtering system eliminates ferromagnetic impurities. The filter consists of a high current coil and an automatic control unit. During the improvement of this unit, a FESTO FPC-404 type controller based on an extended capability PLC was installed. (R.P.) 5 figs

New trends in designing NPP control boards

International Nuclear Information System (INIS)

Kondrat'ev, V.V.

1981-01-01

A short analytical summary of the latest developments and future trends in designing NPP control boards is given. The designs of the Westinghause and the Hynkley-Point NPP control boards are described in detail. The essence of the advanced control board concept consists , firstly, in expanded use of computer-controlled displays for the sake of reducing the content of unimportant information presented to an operator, and, secondary, in better account of human possibilities to convert the NPP operation information into a more suitable form. An enlarged use of the direct digital reactor control utilizing microprocessors is expected. Besides, the employment of full-scale control board mock-ups and information desks as well as testing newly-developed control boards at computer reactor simulators are concluded to be used at all-growing rate [ru

Corrosion behaviour of dissimilar welds between ferritic-martensitic stainless steel and austenitic stainless steel from secondary circuit of CANDU NPP

International Nuclear Information System (INIS)

Popa, L.; Fulger, M.; Tunaru, M.; Velciu, L.; Lazar, M.

2016-01-01

Corrosion damages of welds occur in spite of the fact that the proper base metal and filler metal have been correctly selected, industry codes and standards have been followed and welds have been realized with full weld penetration and have proper shape and contour. In secondary circuit of a Nuclear Power Station there are some components which have dissimilar welds. The principal criteria for selecting a stainless steel usually is resistance to corrosion, and white most consideration is given to the corrosion resistance of the base metal, additional consideration should be given to the weld metal and to the base metal immediately adjacent to the weld zone. Our experiments were performed in chloride environmental on two types of samples: non-welded (410 or W 1.4006 ferritic-martensitic steel and 304L or W 1.4307 austenitic stainless steel) and dissimilar welds (dissimilar metal welds: joints between 410 ferritic-martensitic and 304L austenitic stainless steel). To evaluate corrosion susceptibility of dissimilar welds was used electrochemical method (potentiodynamic method) and optic microscopy (microstructural analysis). The present paper follows the localized corrosion behaviour of dissimilar welds between austenitic stainless steel and ferritic-martensitic steel in solutions containing chloride ions. It was evaluated the corrosion rates of samples (welded and non-welded) by electrochemical methods. (authors)

Assessing the thermal-hydraulic behaviour of steam generators in a CANDU-6 type NPP in the event of MSSV blockage on the open-setting

International Nuclear Information System (INIS)

Dinca, Elena

2004-01-01

This work aims at achieving an analysis regarding the thermal-hydraulic behaviour of a CANDU-6 type NPP in the event of the blockage on open-setting of an MSSV (Main Steam Safety Valve) for steam relief from steam generators. The systems studied are main steam and feedwater mixture in the secondary circuit, particularly being analyzed the behaviour of the steam generators as well as the primary heat transfer and the control system of heavy water pressure and inventory in the primary system. One supposes that the MSSV blockage occurs directly after its opening in the event of an accident that led to the a steam pressure rise in the steam generators up to the threshold value of MSSV o penning. The analysis was applied to two events of initiation which lead to MSSV o penning, namely a Class IV loss of electric supply and loss of vacuum in turbine condenser. In the simulation of the events selected for analysis a long elapse of time is supposed (3600 seconds) and no operator intervention while the NPP is operating at rating power and equilibrium fuel regime. Each of the two events were analyzed for two distinct sets of conditions of event initiation and evolution. The study was focussed on the behaviour of NPP, particularly of the steam generators, and on the estimation of the amount of water in the secondary circuit released into the atmosphere during the event. The analysis is of deterministic type and supplies information required by the Probabilistic Safety Assessment (PSA) applied to nuclear facilities in establishing the operation procedures and documentation. The analysis was based on design data for a CANDU-6 NPP and the HYDN3 code for thermal-hydraulic computation in CANDU type NPPs. In the paper there are presented the analysis, methodology, models, hypotheses and the input data as well as the analyzed cases. Within the computing code some models were developed to allow simulating the event sequences chosen for analyses. The results are plotted and

Influence of the secondary circuit chemistry on the characteristics of the filmed carbon steel components

International Nuclear Information System (INIS)

Radulescu, M.; Pirvan, I.; Dinu, A.; Fulger, M.; Lucan, D.; Anghel, C.

2001-01-01

Some correlations are established between the characteristics of the superficial films formed on the carbon steel components in some operation conditions of a secondary circuit from Nuclear Power Station (NPS), and the specific parameters of the aqueous environment in which these films were formed. The main parameters studied, specific to a secondary circuit environment, are: the value of pH and the substances used to regulate it and, respectively, the oxygen concentration dissolved in the aqueous environment. These filmed samples by autoclaving were studied by: X rays diffraction method; metallographic microscopy and electrochemical methods such as: potentiodynamic and electrochemical impedance spectroscopy (E.I.S.). (R.P.)

Preventing degradation and in-service inspection of NPP steam generator

International Nuclear Information System (INIS)

Ding Xunshen

1999-01-01

The author describes the degradation of steam generator tubes in initial operating stage of France NPP. The author emphatically presents the preventive measures to tackle degradation and In-service inspection of Daya Bay NPP 1 unit as a guarantee of safety operation, including secondary side water chemistry monitoring and controlling, leakage rate monitoring, eddy-current inspection, mechanical cleaning, cleanliness inspection, foreign objects removal and etc

Frequency response analysis of NPP containment with WWER-1000 type reactor

International Nuclear Information System (INIS)

Zoubkov, D.; Isaikin, A.; Shablinsky, G.

2005-01-01

Analysis of vibration load on the building structures of nuclear power plants (NPP) has come to the fore due to extension of their operational lifetime. Such analysis could be carried out if dynamic characteristics test (natural vibration frequency and natural mode) of NPP building structures is conducted in full-scale conditions. In this paper we represent methods of frequency response analysis of the generating unit 1 (RO-1) reactor compartment at Kalininskaya NPP on the basis of technogenic vibration. Main vibration sources of RO-1 are turbine-type generators, main centrifugal pumps and pipelines of power generating units 1 and 2. Vibration of RO-1 has been measured alternately at three points of RO-1 containment which is 76 m high and 47.4 m in diameter: top of the dome (76.0 m), holdout ring (70.3 m), point on the ground next to containment (0.0 m). Three components of vibration velocity have been measured simultaneously at each point: vertical Z-component, horizontal Y-component along the axis of the apparatus room and horizontal X-component across the room axis. Magnetoelectric pendulum-type vibrometers have been used for measurement. They were modernized by ad hoc multiposition amplifier card installed into the sensor body. Vibrometers were connected to the recorder by vibration protected and jam resistant cables. The results of present researches testified that dominant frequencies of X- and Y-oscillation spectra at RO-1 of Kalininskaya NPP (1.7 and 1.9 Hz correspondingly) correspond to the first vibration mode of RO-1 as a rigid construction on elastic foundation. High peaks of spectra at 16.7 and 25 Hz result from vibrations caused by main centrifugal pumps and turbine-type generators and coincide with the number of their revolutions per minute (1000 and 1500 rpm). Other peaks of spectra are related to the vibration of pipelines of primary and secondary circuits. (authors)

Hydrodynamics and sediment transport at Muria Peninsula NPP Site

International Nuclear Information System (INIS)

Heni Susiati; Berni A Subki; Harman A

2011-01-01

Coastal along the coast of the Muria Peninsula, particularly the location of the Muria NPP site candidate is a dynamic region, the interaction between physical oceanographic factors such as currents, waves and tides in the coastal sediments cause abrasion or accretion. Interactions have resulted in coastal dynamics needs to be considered in siting NPP is essential in order to plan. Capacity of hydro-oceanographic data is essential in order to plan the development of the Muria NPP. The process of selecting a safe site for hydro-oceanographic aspects carried out according to IAEA safety standards on site selection. For the evaluation stage of hydro oceanographic potential site (site survey stage), the analysis is more focused on the tidal along the northern coast, bathymetry, potential water resources and hydrologic systems in the Muria NPP siting locations, Jepara. The method used is a secondary, confirmation of field data collection and interpretation of modeling results. The results showed that the preparation for the construction of NPP need to be evaluated further to coastal conditions with respect to the increase coastal erosion in the area of prospective NPP siting. (author)

Dynamic model for tritium build-up at NPP with RBMK type reactors and its enviromental beraviour

International Nuclear Information System (INIS)

Badyaev, V.V.; Egorov, Yu.A.; Ivanov, E.A.; Stegachev, G.F.; Tolstykh, V.D.

1982-01-01

A model of tritium production dynamics for a high power NPP with RBMK type reactors is proposed and investigated. The main ''skeleton'' model structure for forecasting tritium buildup at a NPP and its exchange with the environment has been singled out at a heuristic level. Decomposition and layout of the units have been performed by global functional relations of the investigated objects (NPP and environment). the model accounts for only oxidized tritium forms. Water exchange between the NPP subsystems and environment is the main mechanism for tritium migration. The model does not account for scheduled periodic maintenance work effects, presence of stagnant zones in the station circuits, fuel burn-up, etc. The parametric identification method applied in the model makes the model adaptable to particular situations and considered systems of the NPP and environment. Completing the model with necessary and sufficient experimental data one can pass to certain forecasting problems and to NPP control as a tritium source in the environment

Core Management of NPPs in China and Experience of Tianwan NPP

International Nuclear Information System (INIS)

Guohan, G.

2006-01-01

The Current Status of the NPPs in China; the Nuclear Power Development Plan till 2020; the Fuel Management and the Core Management Strategy of NPPs are briefly presented in this paper. The gained experience during construction of Taiwan NPP, new design features and major construction milestones of Taiwan NPP are also discussed. The full list of 21 non-conformance reports (NCR) submitted by Jiangsu Nuclear Power Company to NNSA during construction of Taiwan NPP is given. The main issues raised during FSAR review like: RP operation with incomplete number of primary loops; Sedimentation in the construction and piping of service water system; Location of postulated pipe break; Stratification analysis for surge line of pressurizer; Safety classification of equipment in primary circuit; Fire resistant capability of cable insulation; Fire Hazard Analysis; Optimization of protection against ionizing radiation ect. are also listed

Operating and mathematical representation of resonances between flow parameters oscillations and structure vibrations of NPP

Energy Technology Data Exchange (ETDEWEB)

Proskuryakov, K.N.; Yang Shan Afshar, E.; Polyakov, N.I. [Nuclear Power Plant Department of Moscow Power Engineering Institute Technical Univ., Moscow (Russian Federation)

2007-07-01

The experimental data that have been obtained from the measurements of noise signals in primary circuit of NPP with reactor of WWER-1000 are presented. The causes of resonant interaction between Eigen-Frequencies of Oscillations of the Coolant Pressure (EFOCP) and structure vibrations are discussed. An application-oriented approach to the problem of identification of abnormal phenomena of thermal-hydraulic parameters is proposed. Logarithmic Decrement {delta} is determined. The bigger damping ratio {zeta} provides bigger {delta} and correspondingly smaller values of Q-factor and amplitude X(t)max. All experimental units intended for NPP severe accident investigation must satisfy to the NPP Q-factor criterion of similarity. (authors)

Operating and mathematical representation of resonances between flow parameters oscillations and structure vibrations of NPP

International Nuclear Information System (INIS)

Proskuryakov, K.N.; Yang Shan Afshar, E.; Polyakov, N.I.

2007-01-01

The experimental data that have been obtained from the measurements of noise signals in primary circuit of NPP with reactor of WWER-1000 are presented. The causes of resonant interaction between Eigen-Frequencies of Oscillations of the Coolant Pressure (EFOCP) and structure vibrations are discussed. An application-oriented approach to the problem of identification of abnormal phenomena of thermal-hydraulic parameters is proposed. Logarithmic Decrement δ is determined. The bigger damping ratio ζ provides bigger δ and correspondingly smaller values of Q-factor and amplitude X(t)max. All experimental units intended for NPP severe accident investigation must satisfy to the NPP Q-factor criterion of similarity. (authors)

Possible pressurized thermal shock events during large primary to secondary leakage. The Hungarian AGNES project and PRISE accident scenarios in VVER-440/V213 type reactor

Energy Technology Data Exchange (ETDEWEB)

Perneczky, L. [KFKI Atomic Energy Research Inst., Budabest (Hungary)

1997-12-31

Nuclear power plants of WWER-440/213-type have several special features. Consequently, the transient behaviour of such a reactor system should be different from the behaviour of the PWRs of western design. The opening of the steam generator (SG) collector cover, as a specific primary to secondary circuit leakage (PRISE) occurring in WWER-type reactors happened first time in Rovno NPP Unit I on January 22, 1982. Similar accident was studied in the framework of IAEA project RER/9/004 in 1987-88 using the RELAP4/mod6 code. The Hungarian AGNES (Advanced General and New Evaluation of Safety) project was performed in the period 1991-94 with the aim to reassess the safety of the Paks NPP using state-of-the-art techniques. The project comprised three type of analyses for the primary to secondary circuit leakages: Design Basis Accident (DBA) analyses, Pressurized Thermal Shock (PTS) study and deterministic analyses for Probabilistic Safety Analysis (PSA). Major part of the thermohydraulic analyses has been performed by the RELAP5/mod2.5/V251 code version with two input models. 32 refs.

Possible pressurized thermal shock events during large primary to secondary leakage. The Hungarian AGNES project and PRISE accident scenarios in VVER-440/V213 type reactor

Energy Technology Data Exchange (ETDEWEB)

Perneczky, L [KFKI Atomic Energy Research Inst., Budabest (Hungary)

1998-12-31

Nuclear power plants of WWER-440/213-type have several special features. Consequently, the transient behaviour of such a reactor system should be different from the behaviour of the PWRs of western design. The opening of the steam generator (SG) collector cover, as a specific primary to secondary circuit leakage (PRISE) occurring in WWER-type reactors happened first time in Rovno NPP Unit I on January 22, 1982. Similar accident was studied in the framework of IAEA project RER/9/004 in 1987-88 using the RELAP4/mod6 code. The Hungarian AGNES (Advanced General and New Evaluation of Safety) project was performed in the period 1991-94 with the aim to reassess the safety of the Paks NPP using state-of-the-art techniques. The project comprised three type of analyses for the primary to secondary circuit leakages: Design Basis Accident (DBA) analyses, Pressurized Thermal Shock (PTS) study and deterministic analyses for Probabilistic Safety Analysis (PSA). Major part of the thermohydraulic analyses has been performed by the RELAP5/mod2.5/V251 code version with two input models. 32 refs.

Lessons learnt from the resin release into the primary circuit of the Fessenheim NPP unit 1 in January 2004. Impact on the nuclear safety

International Nuclear Information System (INIS)

Georgescu, M.

2004-01-01

On January the 24 th , at the Fessenheim NPP unit 1, a human error was committed during a boron demineralizer line-up, caused by lack of preparation. Consequently, a quantity of resin estimated at about 300 liters was released from this demineralizer, through its safety valve, into the head-tank of the chemical and volume control (CVC) system and after that, into the primary circuit. The incident had a real impact on the unit: the CVC filters were clogged, the seal injection flow of the primary circuit main pumps was lost, the primary circuit main pump 2 tripped four days after the incident, as the rate of the recirculated seal leak flow (downstream the seal 1) increased up to the automatic trip set point, the shaft of the running primary circuit feed pump was found seized into the rear hydrostatic bearing following the pump stop (after ten days of successful operation), the thimble plugs were jammed into their guide tubes, the small diameter pipes were plugged. The unit shutdown for over five months was necessary to clean the primary circuit components, repair or replace the affected equipment items and carry out inspections and tests. The reinforced unit in-service monitoring program, set up during the unit start-up, confirms that, up to now, the unit operation has not been adversely affected by the residual amounts of resin which subsist in certain areas of the primary circuit. Nevertheless, it remains to verify that, in the long term, these deposits will have no negative chemical effect in the potential confined areas, such as the thermal barriers of the primary circuit main pumps. Finally, the occurrence of this incident underlines, once more, the importance of normal operating activity preparing and checking. It also reveals the implementation of an ''unforgiving'' design change allowing the installation of a boron demineralizer safety valve having its outlet connected to the primary circuit. (orig.)

Solubility of magnetite in coolant of NPP boiling reactor

International Nuclear Information System (INIS)

Zarembo, V.I.; Kritskij, V.G.; Slobodov, A.A.; Puchkov, L.V.

1988-01-01

To improve water-chemical NPP regimes calculations of iron solubility up to 600 K temperature in Fe 3 O 4 -H 2 O-O 2 and Fe(OH) 3 -H 2 O systems are performed using a system of selected and consistent values of thermal constants of various chemical iron forms in standard aqueous solution state. Calculations have shown that up to 423 K in aqueous medium containing oxygen, magnetite is unstable and is oxidized first up to Fe(OH) 3 and then - up to Fe OOH and Fe 2 O 3 . Calculations complying with experimental data have demonstrated the presence of maximum on the curve solubility-temperature in desalinized water containing 10 μkg/kg of oxygen. A sequence of processes of oxygen effect on water regime and corrosion prduct deposition in a condensate-feed circuit of NPP boiling reactor is proposed. It is proved that under oxygen water chemistry of condensate-feed circuit after magnetite transfomation into gematite, reduction of soluble iron form inlet to reactor loop occurs, which allows one to expect reduction of γ-radiation dose rate buildup around the primary loop pipelines

Corrosion Behavior of Carbon Steel Coated with Octadecylamine in the Secondary Circuit of a Pressurized Water Reactor

Science.gov (United States)

Jäppinen, Essi; Ikäläinen, Tiina; Järvimäki, Sari; Saario, Timo; Sipilä, Konsta; Bojinov, Martin

2017-12-01

Corrosion and particle deposition in the secondary circuits of pressurized water reactors can be mitigated by alternative water chemistries featuring film-forming amines. In the present work, the corrosion of carbon steel in secondary side water with or without octadecylamine (ODA) is studied by in situ electrochemical impedance spectroscopy, combined with weight loss/gain measurements, scanning electron microscopy and glow-discharge optical emission spectroscopy. The impedance spectra are interpreted using the mixed-conduction model to extract kinetic parameters of oxide growth and metal dissolution through it. From the experimental results, it can be concluded that ODA addition reduces the corrosion rate of both fresh and pre-oxidized carbon steel in secondary circuit significantly by slowing down both interfacial reactions and transport through the oxide layer.

Modeling the critical safety functions status tree of a NPP using FPGA

International Nuclear Information System (INIS)

Farias, Marcos Santana; Oliveira, Mauro Vitor de; Jaime, Guilherme Dutra Gonzaga; Almeida, Jose Carlos Soares de; Augusto, Silas Cordeiro

2013-01-01

Field Programmable Gate Arrays (FPGAs) based systems and equipment are beginning to appear in new plants I and C applications, as well as in retrofits for operating plants, in particular for safety applications due to their capability to face the systems obsolescence since they are circuit independent. The circuits implemented can be portable to different FPGAs architectures. Moreover, they reduce complexity for regulatory approval as compared to conventional microprocessor-based systems. Critical safety function (CSF) is the most significant design concept for prioritize operator actions for NPP based on the potential threat to the three barriers (fuel cladding, primary coolant system boundary, and containment) and allows the operator to respond to these threats prior to event diagnosis. CSF has a hierarchical information structure that organizes the system variables affecting the plant safety in terms of goal-means relations. This paper describes the application of FPGA in the implementation of the CSFs status tree logic for a Westinghouse 3-loops NPP simulator. (author)

Benchmark analysis of three main circulation pump sequential trip event at Ignalina NPP

International Nuclear Information System (INIS)

Uspuras, E.; Kaliatka, A.; Urbonas, R.

2001-01-01

The Ignalina Nuclear Power Plant is a twin-unit with two RBMK-1500 reactors. The primary circuit consists of two symmetrical loops. Eight Main Circulation Pumps (MCPs) at the Ignalina NPP are employed for the coolant water forced circulation through the reactor core. The MCPs are joined in groups of four pumps for each loop (three for normal operation and one on standby). This paper presents the benchmark analysis of three main circulation pump sequential trip event at RBMK-1500 using RELAP5 code. During this event all three MCPs in one circulation loop at Unit 2 Ignalina NPP were tripped one after another, because of inadvertent activation of the fire protection system. The comparison of calculated and measured parameters led us to establish realistic thermal hydraulic characteristics of different main circulation circuit components and to verify the model of drum separators pressure and water level controllers.(author)

Ways of solving the problem of NPP evaporate concentrate storage

International Nuclear Information System (INIS)

Dmitriev, S.A.; Lifanov, F.A.; Savkin, A.E.; Lashchenov, S.M.

2000-01-01

The use of next engineering operations: isotope separation using oxidation, filtration and selective sorption methods, hardening and long term secondary radioactive waste disposal (cement compound from filtration stage and depleted sorbent on filters); concentration and preparation of dry salts from the radionuclide-free stillage residues were proposed for NPP waste reprocessing. The laboratory and pilot tests that demonstrated the possibility for purification of NPP stillage residues from radionuclides to the levels less than maximum permissible ones were conducted. The purified stillage residues are sent for the burial after drying. The calculations of material flows are treated by the example of the Kursk NPP stillage residue and the scheme of the waste retrieval is given [ru

Chemistry monitoring and diagnostic system at NPP Jaslovske Bohunice

International Nuclear Information System (INIS)

Smiesko, Ivan; Figedy, Stefan

2012-09-01

This paper provides a description of water chemistry monitoring and diagnostic system installed at Slovak NPP Jaslovske Bohunice. System has complex architecture and covers laboratory data, chemistry and radiochemistry on-line monitoring data, process data acquisition and processing and diagnostics. Pre-filtered data from process computer and chemistry on-line monitors are recorded together with laboratory data in the ORACLE-based information system CHEMIS with many presentation and processing features. Brief information is given about the basic features of a newly developed diagnostic system for early detection and identification of anomalies incoming in the water chemistry regime of the primary and secondary circuit of VVER-440 type unit. This system, called SACHER (System of Analysis of Chemical Regime) has been installed within the major modernization project at the NPP Bohunice in the Slovak Republic. System SACHER has been developed fully in MATLAB environment. Diagnostic system works exclusively with available on-line data as an operation personnel support application allowing effective response to adverse chemistry events/trends. The availability of prompt information about the chemical conditions of the primary and secondary circuit is very important in order to prevent the undue corrosion and deposit build-up processes within the plant systems. The typical chemical information systems that exist and work at the NPPs give the user values of the measured quantities together with their time trends and other derived values. It is then the experienced user's role to recognize the situation the monitored process is in and make the subsequent decisions and take the measures. The SACHER system, based on the computational intelligence techniques, inserts the elements of intelligence into the overall chemical information system. It has the modular structure with the following most important modules: - normality module- its aim is to recognize that the process

SODEXPERT: help to PWR plant management to prevent secondary circuit corrosion

International Nuclear Information System (INIS)

Eon-Duval, P.; Fiquet, J.M.; Langlet, J.P.

1996-01-01

Since about 10 years, problems of secondary circuit corrosion have raised for PWR plant management. The watch staff can't be asked the physicochemical knowledge requested for a proper interpretation of the various probes outputs. So an expert-system has been performed to help the identification of dangerous situation from a corrosion point of view, and immediately start the PWR managing action. This software has been successfully tested and validated. (D.L.). 5 figs., 4 photos

Using of new chemical regime on secondary circuit in nuclear power plant 'Kozloduy' - Bulgaria

International Nuclear Information System (INIS)

Minkova, K.; Stanchev, S.; Kalpakchiev, Z.

2010-01-01

There are two WWER-1000 - Russian design units (№5 and №6) working in the Bulgarian Nuclear Power Plant 'Kozloduy', which are equipped with horizontal steam generators. The report describes the chronology of the stages in the improvement of the water chemistry regime on the secondary circuit at both of the units 5 and 6 from their start up till now. As a final result of our purposeful activity is done a full exchange of copper alloys with stainless steel in regenerative LP heat exchangers and condensers in the secondary circuit equipment. That way we created preconditions for cardinal change and improvement of the water chemistry regime of the circuit. For that purpose is realized a program for optimization in maximal degree of the water chemistry regime of the secondary circuit of the WWER-1000 Units. The program includes the preliminary study, the stage of experimental operation and the stage of establishing the new regime into regular exploitation. The preliminary study included the definition of the coefficients of distribution of the ammonia in a real operation conditions in the secondary circuit and rating the expected results from the applying of different varieties of the secondary circuit water chemistry. It is taken into account the balance plans for distribution of the corrective reagents, the expected pH values at working temperature (pHt), the transport of products of corrosion to steam generators and the abilities of the installation for purification of the blow down water. As a final result a mixed ammonia-ethanolamine water chemistry regime has been chosen, characterized with pH 25 =9.9(9.85-9.95). The special feature of this regime is that, both the corrective reagents ethanolamine and ammonia are dosed in the feed up water as a mixed solution with permanent proportion of the concentrations. This water chemistry treatment combines the advantages of high ammonia AVT water chemistry related to specific constructive steels in low

Ideal scaling of BETHSY 9.1.B test results to NPP

International Nuclear Information System (INIS)

Petelin, S.; Guntel, I.

1995-01-01

The transient scenario standard problem 27 (ISP-27) was implemented in the RELAP5 analysis of small break loss of coolant accident for Krsko nuclear power plant (Krsko NPP). The objective was to evaluate the effectiveness of ISP-27 proposed accident management procedure for real NPP and to compare the physical phenomena known from experimental background with the phenomena predicted by RELAP5 simulation of real plant transient. The analyses showed that, if relevant break, power scaling criteria, primary and secondary pressure are fulfilled the RELAP5 model of Krsko NPP cannot completely ensure the simulation of typical thermal-hydraulic phenomena observed in BETHSY facility during ISP-27. Much better satisfaction is observed on ideal scaled up model. (author)

The effect of the PWR secondary circuit water chemistry on erosion corrosion

International Nuclear Information System (INIS)

Kaplan, J.

1993-07-01

The secondary circuit of WWER-440 and WWER-1000 reactors is described. The causes of erosion corrosion are outlined, and the effects of the physical properties and chemical composition of water are discussed with emphasis on specific conductivity and concentrations of oxygen, ammonia, iron, sodium, silicon and organics. Described are corrective actions to eliminate the deviations from the normal state during reactor power reduction or reactor shutdown. (J.B.)

Analysis of the ASME methodology for evaluation of erosion-corrosion defects with respect to the differences in the calculation and in materials used at the Dukovany NPP

International Nuclear Information System (INIS)

Kadecka, P.

1995-01-01

The problem of evaluation of tolerable defects and thinning of pipe walls was analyzed. In fact, a procedure for evaluation of tolerable defects is described in ASME Code Case N 480 based on the ASME ''Rules for Construction of Nuclear Power Plant Components''. The pipe systems of the Dukovany NPP, however, were constructed to different (East European) standards, and therefore caution should be exercised when applying US standards to this plant. The report demonstrates major differences between the ASME Standard and the proposed Czech standard ''A.S.I. Standards Documentation for Strength Calculations of Equipment and Piping of WWER Type Nuclear Power Plants'' developed by the Czech Association of Mechanical Engineers (A.S.I), evaluates the applicability of Code Case N 480 to the Dukovany plant, and proposes a Czech procedure for the evaluation. The basic characteristics of materials cited by ASME II and carbon steels used in the secondary circuit of the Dukovany NPP are also compared. (P.A.). 78 tabs., 2 figs., 4 refs

Forecasting of resonances vibration equipment with elastic waves coolant and with the external periodic loads on NPP with WWER

International Nuclear Information System (INIS)

Proskuryakov, K.N.; Zaporozhets, M.V.; Fedorov, A.I.

2015-01-01

Forecasting are carried out for external loads in relation to the main circulation circuit - dynamic loads caused by the rotation of the MCP, dynamic loads caused by the earthquake, dynamic loads caused by damage to the MCP in the earthquake. A comparison of the response spectrum of one of the variants of the base of the NPP, with the frequency vibration of the primary circuit equipment for NPP with WWER-1000 and self-frequency of elastic waves in the fluid. Analysis of the comparison results shows that the frequency of vibration of the main equipment of the reactor plant and elastic waves are in the frequency band in the spectrum response corresponding to the maximum amplitude of the seismic action [ru

Fuel assembly leakage, unit 4, cycle 22, Paks NPP

International Nuclear Information System (INIS)

Szecsenyi, C.; Burjan, T.; Torma, B.; Bona, G.

2009-01-01

At the beginning of Cycle 22, Unit 4, Paks NPP the Iodine isotopes activity concentrations raised irregularly in the water of the primary circuit. Analysis supposed that from 1 to 10 fuel rods in one or more newly loaded follower assemblies had lost their integrity. Due to the fact it was not necessary to shut down the reactor, but at the end of the cycle sipping tests were performed for the entire core to find out the facts using a telescope sipping device supplied by H and B Co., Germany. This paper describes the circumstances of the emergence of the problem, the operational inspection and limitation rules in Paks NPP, the theoretical analysis to estimate the scope and kind of the problem, the sipping device and the measurement/evaluation methods applied for the practical tests, fulfilment the tests, the results and their evaluation and the conclusions regarding the event. (Authors)

Fuel assembly leakage, Unit 4, Cycle 22, Paks NPP

International Nuclear Information System (INIS)

Szecsenyi, Z.; Burjan, T.; Torma, B.; Bona, G.

2009-01-01

At the beginning of Cycle 22, Unit 4, Paks NPP the Iodine isotopes activity concentrations raised irregularly in the water of the primary circuit. Analysis supposed that from 1 to 10 fuel rods in one or more newly loaded follower assemblies had lost their integrity. Due to the fact it was not necessary to shut down the reactor, but at the end of the cycle sipping tests were performed for the entire core to find out the facts using a telescope sipping device supplied by H and B Co., Germany. This paper describes the circumstances of the emergence of the problem, the operational inspection and limitation rules in the Paks NPP, the theoretical analysis to estimate the scope and kind of the problem, the sipping device and the measurement/evaluation methods applied for the practical tests, fulfilment the tests, the results and their evaluation and the conclusions regarding the event. (authors)

Radiation monitoring in the NPP environment, control of radioactivity in NPP-environment system

International Nuclear Information System (INIS)

Egorov, Yu.A.

1987-01-01

Problems of radiation monitoring and control of the NPP-environment system (NPPES) are considered. Radiation control system at the NPP and in the environment provides for the control of the NPP, considered as the source of radioactive releases in the environment and for the environmental radiation climate control. It is shown, that the radiation control of the NPP-environment system must be based on the ecological normalization principles of the NPP environmental impacts. Ecological normalization should be individual for the NPP region of each ecosystem. The necessity to organize and conduct radiation ecological monitoring in the NPP regions is pointed out. Radiation ecological monitoring will provide for both environmental current radiation control and information for mathematical models, used in the NPPES radiation control

Corrosion Product Measurements to ensure integrity of the Steam Generators in Beznau NPP

International Nuclear Information System (INIS)

Mailand, Irene; Franz, Patrick; Venz, Hartmut

2012-09-01

The Nuclear Power Plant Beznau comprises two identical 380 MWe PWR units with two loops each, commissioned in 1969 and 1971. Westinghouse was responsible for the primary part of the plant and BBC/ABB for the secondary circuit. The original materials used in the secondary systems were made of several copper-based alloys, such as for the Condensers, the Low Pressure Pre-heaters and the Moisture Separator Re-heater. The original Steam Generator Tubes were made of Inconel 600 MA. Regarding its age, the NPP Beznau has to be qualified as an old plant. However, in fact particularly in the last 20 years the plant has undergone an extensive modernisation programme in which about 1.5 billion Swiss Francs have been invested. Important measures were the replacements of the Steam Generators with tubes comprising Inconel 690 TT which was realized at unit 1 in 1993 and at unit 2 in 1999. Copper was completely banished from the secondary system and replaced by stainless and chromium steel. The Condensers were fitted with titanium tubes. The secondary water chemistry had to be changed by these replacements and moved step by step from Low-AVT with a pH of about 9.3 to High-AVT with a pH of 9.8 to 9.9, currently. To ensure the integrity of the new Steam Generators as well as of the whole Secondary System a corrosion product programme was introduced at the end of the Nineties. Several investigations which are performed periodically are represented by analyses of corrosion products, measurements of sludge mass and composition in the Steam Generators, Hide-Out-Return- and mass balance measurements of corrosion products in the whole circuit. Objectives of these investigations are assessments of the efficiency of the water chemistry and trend considerations regarding to the transport of corrosion products and pollutants into the Steam Generator, as well as of the potential danger of deposits and stored or absorbed pollutants. The main target of all measures is to avoid any chemical

Development of contact scanner for Wolsung NPP alarm and annunciation system

Energy Technology Data Exchange (ETDEWEB)

Oh, Eung Se [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center

1995-12-31

Contact scanner system in Wolsung NPP(model ESE-1565) is early `70 equipment so most of components are obsolete. To make 100% compatible PCBs for this system is main object of the study. Most of components used in the system are now not available in the electric market, furthermore original system maker no longer supplies spare parts. System supplier(AECL) quoted lots of money than general PCBs prices in case of spare PCBs are re-marked by canada maker. Contents and scope of the study are specifications research and system analysis, improvements of repairability and reliability, circuit design and simulations using computer aided tools(CAE), make arbitrary mechanical contacts signal generator for test system. Now the long-run test of home made PCBs are conducting at Wolsung NPP. (author). 20 refs., 42 figs.

Nuclear power plant V-1

International Nuclear Information System (INIS)

1999-01-01

In this leaflet the short history of commissioning of Bohunice V-1 NPP is reviewed (beginning of construction 24 April 1972; First controlled reactor power, Reactor Unit 1 (RU1): 27 November 1978, Reactor Unit 2 (RU2): 15 March 1980; Connection to the grid: RU1 17 December 1978, RU2 26 March 1980; Commercial operation: RU1 1 April 1980, RU2 7 January 1981. The scheme of the nuclear reactor WWER 440/V230 is depicted. The major technological equipment (primary circuit, nuclear reactor, steam generators, reactor coolant pumps, primary circuit auxiliary systems, secondary circuit, turbine generators, NPP electrical equipment, and power plant control) are described. Technical data of the Bohunice V-1 NPP are presented

Technology for NPP decantate treatment realized at Kola NPP

International Nuclear Information System (INIS)

Stakhiv, Michael; Avezniyazov, Slava; Savkin, Alexander; Fedorov, Denis; Dmitriev, Sergei; Kornev, Vladimir

2007-01-01

At Moscow SIA 'Radon' jointly with JSC 'Alliance Gamma', the technology for NPP Decantate Treatment was developed, tested and realized at Kola NPP. This technology consists of dissolving the salt residue and subsequent treatment by ozonization, separation of the deposits formed from ozonization and selective cleaning by ferro-cyanide sorbents. The nonactive salt solution goes to an industrial waste disposal site or a repository specially developed at NPP sites for 'exempt waste' products by IAEA classification. This technology was realized at Kola NPP in December 2006 year. At this time more than 1000 m 3 of decantates log time stored are treated. It allows solving very old problem to empty decantates' tanks at NPPs in environmentally safe manner and with high volume reduction factor. (authors)

Analysis of the current status of measuring chains of the in-service diagnosis system at the Dukovany NPP

International Nuclear Information System (INIS)

Stulik, P.; Sipek, B.

2006-02-01

The following systems were analyzed for the Dukovany NPP: Monitoring of primary circuit and reactor vibrations; Detection of loose parts; Main coolant pump diagnosis; Reactor internals diagnosis; and Turbogenerator status monitoring. Recommendations were derived from the findings. (P.A.)

Intelligent system for accident identification in NPP; Sistema inteligente para la identificacion de accidentes en centrales nucleares

Energy Technology Data Exchange (ETDEWEB)

Hernandez, J L [Centro Nacional de Seguridad Nuclear, La Habana (Cuba)

1999-12-31

Accidental situations in NPP are great concern for operators, the facility, regulatory bodies and the environmental. This work proposes a design of intelligent system aimed to assist the operator in the process of decision making initiator events with higher relative contribution to the reactor core damage occur. The intelligent System uses the results of the pre-operational Probabilistic safety Assessment and the Thermal hydraulic Safety Analysis of the NPP Juragua as source for building its knowledge base. The nucleus of the system is presented as a design of an intelligent hybrid from the combination of the artificial intelligence techniques fuzzy logic and artificial neural networks. The system works with variables from the process of the first circuit, second circuit and the containment and it is presented as a model for the integration of safety analyses in the process of decision making by the operator when tackling with accidental situations

Uninterruptible power supply model of independent voltage inverter of NPP electrical equipment

International Nuclear Information System (INIS)

Rozhkov, V.V.; Ajdaralieva, V.Eh.

2010-01-01

A package of main transforming units models of advanced uninterruptible power supply systems of NPP electrical equipment was developed. The package of models allows investigating the basic modes of uninterruptible power supply systems operation by computer modeling. Simulation results were presented. Recommendations on choice of parameters of power circuit elements as well as on diagnostics and adjustment of regulators of converters control systems were given [ru

Simulation and System Analysis of Flow Pulsation at Normal and Emergency for Advanced On-line Monitoring and Control of NPP

International Nuclear Information System (INIS)

Proskouriakov, K.N.; Moukhine, V.S.

2002-01-01

In addition to investigation of thermal-hydraulic processes on NPP with use of computer codes the new system analysis of flow pulsation is worked out. System analysis shows that properties of heat rejection circuits of NPP as oscillatory system are not equal the sum of properties of its separate elements but gives the new properties which must be taken into account. Methods have been worked out for calculating and identifying the sources of thermal-hydraulic disturbances are intended to improve the means of early diagnostics of anomalies in the technological process, to forecast their development, to improve the efficiency of overhauling operations and safety in operation, and also to create advanced on-line monitoring and control of NPP. Conception of the control system development presents. Proposal for main topics R and D areas for advanced NPP monitoring, diagnostic and control are identified. (authors)

Electrohydraulic system to control NPP turbines

International Nuclear Information System (INIS)

Kosyak, Yu.F.; Virchenko, M.A.; Rozhanskij, V.E.; Rokhlenko, V.Yu.; Gapunin, A.Ya.; Zhornitskaya, T.Ya.; Rasskazov, I.Eh.; Butsenko, V.N.; Brajnin, L.S.; Makarenko, N.I.

1985-01-01

Operation regimes of electrohydraulic regulation system (EHRS) of NPP turbines, designed to control the turbine in start-up and working conditions, have been decribed. In start-up regimes EHRS ensures the testing of control valves of the turbine, the turn of the turbine from zero to the nominal rotation frequency (automatic, semiautomatic and manual regulation), turbine acceleration to test safety automatic systems, gradual change in rotation frequency during generator synchronization with circuit. Under working conditions EHRS ensures the maintenance of frequency, power and vapour pressure before the turbine. A block diagram of EHRS is presented. Sensors and electronic part of EHRS are supplied with triple reservation, which ensures a high relaibility of the system

Decommissioning of Brennilis NPP

International Nuclear Information System (INIS)

Baize, Jean-Marc

1998-01-01

This EDF press communique give information related to the decommissioning of the Brennilis NPP. The following five items are developed in this report: 1. the level-2 decommissioning operations at the Brennilis NPP; 2. the Brennilis NPP, a pilot operation from the commissioning up to the decommissioning; 3. history of the Brennilis NPP decommissioning; 4. the types of radioactive wastes generated by the Brennilis NPP decommissioning; 5. the Brennilis NPP - a yard management as a function of the wastes. The document contains also seven appendices addressing the following subjects: 1. the share of decommissioning assigned to EDF and the decommissioning steps; 2. the EDF installations in course of decommissioning; 3. the CEA decommissioned installations or in course of decommissioning; 4. regulations; 5. costs; 6. waste management - principles; 7. data on the decommissioning yard

Decommissioning of NPP A-1

International Nuclear Information System (INIS)

Anon

2009-01-01

In this presentation the Operation history of A1 NPP, Project 'Decommissioning of A1 NPP' - I stage, Project 'Decommissioning of A1 NPP ' - II stage and Next stages of Project 'Decommissioning of A1 NPP ' are discussed.

Nonvascular contribution to ecosystem NPP in a subarctic heath during early and late growing season

DEFF Research Database (Denmark)

Campioli, Matteo; Samson, Roeland; Michelsen, Anders

2009-01-01

significant when vascular plants are less active and ecosystems act as a source of carbon (C). To clarify these dynamics, nonvascular and vascular aboveground NPP was compared for a subarctic heath during two contrasting periods of the growing season, viz. early-mid summer and late summer-early autumn...... measurements of shoot length increase. Vascular NPP was determined by harvesting shrub and herb apical growth and considering production due to stem secondary growth of shrubs. Hylocomium splendens and Pleurozium schreberi showed highest biomass growth in late summer, whereas for D. elongatum this occurred...... weight m-2 d-1, in early and late summer, respectively, whereas in the same periods vascular NPP was 3.6 and 1.1 g dry weight m-2 d-1. The contribution of nonvascular NPP to total aboveground NPP was therefore minor in early summer but substantial in late summer, when 25% of the C accumulated...

Control circuit for transformer relay

International Nuclear Information System (INIS)

Wyatt, G.A.

1984-01-01

A control circuit for a transformer relay which will automatically momentarily control the transformer relay to a selected state upon energization of the control circuit. The control circuit has an energy storage element and a current director coupled in series and adapted to be coupled with the secondary winding of the transformer relay. A device for discharge is coupled across the energy storage element. The energy storage element and current director will momentarily allow a unidirectional flow of current in the secondary winding of the transformer relay upon application of energy to the control circuit. When energy is not applied to the control circuit the device for discharge will allow the energy storage element to discharge and be available for another operation of the control circuit

Study and optimization of operating regimes of NPP district heating system

International Nuclear Information System (INIS)

Bunin, V.S.; Vasil'ev, M.K.; Kudryavtsev, A.A.; Gorbashev, Yu.B.; Gadzhij, V.M.

1980-01-01

Thermal tests of the system with two reactors and four turbines have been carried out for the purpose of verification of operating regimes of the NPP district heating system with boiling single-curcuit RBMK-1000 reactors and K-500-65/3000 turbines. The system is designed for heat supply of habitable settlement and industrial site. The data processing have been carried out by the BESM-6 computer representing distributions of heat flow, steam, water and their parameters and determining the main energy indices of the system. Calculations of the system operating regime variables during the year have been carried out with the help of this program. It has been expected that the system provided heat consumption of 232 MW at calculated regime of thermal loading of the district, temperature regime of the system water of 130/170 deg C, relative load of hot water supply of 0.2 and duration of heating period of 4800 h. Calculations demonstrated that distric heat supply by NPP allowed one to supplant about 85 thous. of reference fuel/year of organic fuel. About 63 thous. of reference fuel/year are required for compensation of decrease of electric energy production in a condensation cycle. It has been also shown, that replacing the four-stroke system heaters by one-stroke heaters permits to drop system water underheating 1.5 times and, respectively, electric energy underproduction to 72 mln Mj (20 mln, kWxh). It produces additional economy of 6.6 thous. reference fuel/year. Calculations of its heat system have been conducted in order to determine the influence of water consumption in an intermediate circuit on the system efficiency. It has been shown that with the increase of water consumption energy power losses decrease. Thus, the above studied have demonstrated that the use of the single-circuit NPP district heating systems leads to considerable economy of fuel

Inter granular stress corrosion cracking of Ignalina NPP austenitic piping of outside diameter 325 mm

International Nuclear Information System (INIS)

Nedzinskas, L.; Klimasauskas, A.

2003-01-01

The Inter Granular Stress Corrosion Cracking (IGSCC) of Ignalina NPP main circulation circuit piping, produced from austenitic stainless steel is presented covering current performances and further 'Ageing Management' related actions and plans as well as experience (lessons learned) on solving IGSCC phenomenon, which is currently under investigations and no yet comprehensive answer how to avoid it. (author)

Simulation of the dynamic behaviour of the secondary circuit of a WWER-440 type nuclear power plant Pt. 2

International Nuclear Information System (INIS)

Doorenbos, J.; Gacs, A.; Kiss, Zs.

1987-12-01

This report describes the dynamic simulation models of the most important controllers of the secondary circuit of a WWER-440 type nuclear power plant, i.e., the hydraulic turbine controller and the level controls of the condenser hotwell and that of the feedwater tank. Simulation results are also presented. (For dynamic simulation models of the primary circuit of WWER-440 type reactors see Reports KFKI--1983-127 and KFKI--1985-08.) (author) 15 figs

Mochovce NPP simulator

International Nuclear Information System (INIS)

Ziakova, M.

1998-01-01

Mochovce NPP simulator basic features and detailed description of its characteristics are presented with its performance, certification and application for training of NPP operators as well as the training scenario

About water chemistry influence on equipment reliability of NPP with RBMK-1000

International Nuclear Information System (INIS)

Berezina, I.G.; Styazhkin, P.S.; Kritskij, V.G.

2001-01-01

In the paper the experience of a quantitative valuation of coolant quality influence on a reliability of some equipment elements of NPP with RBMK-1000 is offered. The choice is made of coolant quality integral parameter. The connection between indices values of coolant quality and reliability of major elements of circulation circuit equipment (including fuel claddings) is established. The reliability improvement of equipment elements operation is supported by high water chemistry quality. (orig.)

Two managerial grids in NPP

International Nuclear Information System (INIS)

Zhao Hui

2012-01-01

Today, the nuclear power corporation (NPC) enjoys the profit of LCEP (the low carbon economic policy). at the same time, they also enduring more and more pressure. For example, the partner competition or the NPP potential occupational risk . The efficient counterplot of risk is the self-ability cultivation. It is essential to research the NPP managerial flow. The nuclear power plant (NPP) unit is a carrier of the NPC enterprise management system, and has taken on a new look 'pull one portion then the whole moving'. The NPP has three systematical characters, the security responsibility center, the man-machine system and the input-output system. The manufacturing system and the enterprise management system are the great constituents of the NPP managerial flows. Means of systems analysis, we can find out the truth of the NPP running interface. In CHINA, there are many operating experiences near 20 years. It indicates that the NPP manufacturing system and the enterprise system are the roots of the nuclear power corporation, the core of the all NPP systems must be based on it. So the ability cultivation is the work core to NPP. It is reliably to ensure the NPP to be up against problems, for instance, the security duty, the costing control and the man-machine system running harmoniously. This paper introduces the NPP managerial flow and the present state of QNPC, also come up with a proposal to refer for the NPC development actions of collective measure, specialization, standardization, fine. (author)

Monitoring of primary circuit and reactor of NPP A-1

International Nuclear Information System (INIS)

Prazska, M.; Majersky, M.; Rezbarik, J.; Sekely, S.; Vozarik, P.; Walthery, R.; Stuller, P.

2005-01-01

Nuclear Power Plant A-1 in Jaslovske Bohunice was commissioned in 1972. Heavy water moderated, carbon dioxide cooled channel type reactor was shut down after two accidents in 1977. During more serious second accident, the reduced coolant flow caused local overheating of the fuel and consequent damage/melting of the fuel channel. Both accidents had led to the damage of several fuel assemblies with extensive local damage of fuel claddings. As a consequence, the main cooling circuit was significantly contaminated by fission products and long-life alpha nuclides. The detailed monitoring of dose rates, smearable contamination and sampling of contamination was performed. Extended monitoring in reacto vessel, primary circuit pipes, turbo-compressors, steam generators, main valves, gas tanks and also heavy water system with collectors, coolers, distilling and purification station, pumps and valves was done. Appropriate devices and procedures for the monitoring and examination of the installations were prepared and applied. Obtained results will serve for the future planning of the decontamination and decommissioning works. The 3-D model of the reactor that had been developed as part of this Project proved invaluable for orientation, visualisation, planning and analysis of results. Dose rates were measured in the technological channels from the reactor hall floor to the bottom of the hot gas chamber in decrements of 1 m and 0.5 m. The highest absolute values of dose rates were found in channels located in the middle of the reactor (up to 1900 mGy/h in the active zone region). It is estimated that the total contaminated area of primary circuit equipment (pipework, steam generators and turbo-compressors) is some 48 000 m 2 . It follows that the total gamma contamination is of the order of 10 14 to 10 15 Bq and total alpha contamination 10 11 to 10 13 Bq. The total amount of deposits in the gas circuit is about 14.3 tons. (authors)

Changing NPP consumption patterns in the Holocene: from Megafauna "liberated" NPP to "ecological bankruptcy"

Science.gov (United States)

Doughty, C.

2015-12-01

There have been vast changes in how net primary production (NPP) is consumed by humans and animals during the Holocene beginning with a potential increase in availability following the Pleistocene megafauna extinctions. This was followed by the development of agriculture which began to gradually restrict availability of NPP for wild animals. Finally, humans entered the industrial era using non-plant based energies to power societies. Here I ask the following questions about these three energy transitions: 1. How much NPP energy may have become available following the megafauna extinctions? 2. When did humans, through agriculture and domestic animals, consume more NPP than wild mammals in each country? 3. When did humans and wild mammals use more energy than was available in total NPP in each country? To answer this last question I calculate NPP consumed by wild animals, crops, livestock, and energy use (all converted to units of MJ) and compare this with the total potential NPP (also in MJ) for each country. We develop the term "ecological bankruptcy" to refer to the level of consumption where not all energy needs can be met by the country's NPP. Currently, 82 countries and a net population of 5.4 billion are in the state of ecologically bankruptcy, crossing this threshold at various times over the past 40 years. By contrast, only 52 countries with a net population of 1.2 billion remain ecologically solvent. Overall, the Holocene has seen remarkable changes in consumption patterns of NPP, passing through three distinct phases. Humans began in a world where there was 1.6-4.1% unclaimed NPP to consume. From 1700-1850, humans began to consume more than wild animals (globally averaged). At present, >82% of people live in countries where not even all available plant matter could satisfy our energy demands.

Failed (leaking) spent fuel management and storage in the Paks NPP

International Nuclear Information System (INIS)

Burjan, T.

2011-01-01

At the cycle 22, unit 4, Paks NPP the fissile contents raised irregularly in the water of the primary circuit. At the end of the cycle sipping tests were performed for the entire core to find out the leaking fuel assembly primarily responsible for this phenomenon. The identified leaking assembly temporarily was placed in the Spent Fuel Relaxing Pool. For measuring environmental impact of leaking assemblies an investigation program was developed and implemented. The assessment covered the following: effects of the leaking fuel on the water of relaxing pool and on the gaseous emissions in case open storage; in case when the leaking cassette is in a special hermetical storage case, how much gas is collected in the locked case and what is its composition; how to change the measured sipping test signal depending on relaxing time of leaking fuel cassettes. Based on the evaluation of the investigation program results the NPP modified the operational instructions for the treatment and storage of failed fuel assemblies. (author)

Water Quality of NPP Secondary Side with Combined Water Chemistry of Ammonia and Ethanolamine

International Nuclear Information System (INIS)

Rhee, In-H.; Jung, Hyun-jun; Cho, Daechul; Park, Byunggi

2012-09-01

Ammonia (AM) and Ethanolamine (ETA), as pH control additive agents, were injected to the secondary side in a Korean NPP for the even pH in the entire secondary system including the wet region and the condensate. Ammonia and ETA are dominant in the vapor and liquid phases, respectively, since the former and latter are more and less volatile than water in the temperature range of 30 to 300 . pH of 9.5 to 9.7 was maintained in the water-steam cycle at the concentrations of ammonia with ∼1.0 ppm and ETA of ∼1.8 ppm. From the standpoint of corrosion, i.g, concentration of Fe, the water quality of secondary side was improved by the combined water treatment of ammonia and ETA, compared to all volatile treatment of ammonia. The electrical conductivity was increased from 6 to 10 μS/cm due to the presence of organic carboxylates produced by the decomposition of ETA. ETA was broken down by <5% in steam generator and converted into formate, acetate, and glycolate, among which acetate was largely formed. But inorganic ions such as Na + , Cl - , and SO 4 2- are not changed because their ingress was not made and the selectivity of resin over those ions was not fairly altered. The runtime of demineralizer in steam generator blowdown was shortened by a third for a mixture of ammonia and ETA. Most of Fe was originated from the shell side of heat exchangers including the condenser as a result of corrosion. Fe was only eliminated by ion exchange demineralizers, i.e., 46% at CPP and 3% at SG BD and 70% of Fe oxides were accumulated at the steam generator, on the basis of Fe concentration at the final feedwater. In conclusion, ETA is preferable to ammonia for the enhancement of pH in the liquid phase of water-steam mixture such as the shell side of heat exchanger and also the full-flow operation of CPP is more desirable than partial-flow operation for the improved removal of corrosion products, regardless of hydrogen- or amine-type operation. (authors)

Main directions of works on radioactive waste management at 30-km zone near the Chernobyl' NPP

International Nuclear Information System (INIS)

Grushinskij, B.Ya.; Komarov, V.I.; Proskuryakov, A.N.; Kham'yanov, L.N.; Khubizov, S.B.; Ignatenko, E.I.; Ryzhkova, V.N.; Luppov, V.A.; Matskevich, G.V.; Frolov, V.N.

1989-01-01

Main points and stages of creating an specialized enterprise for centralized reprocessing and radioactive waste disposal are considered. The enterprise is intended for collection conditioning and burial of all types of radioactive wastes, formed during liquidation of accident effect at the Chernobyl' NPP as well as forming in operation of NPP. The enterprise is also used to decontaminate equipment and constructions, for reprocessing of secondary radioactive wastes forming during decontamination process of equipment constructions, transport and work clothes

NPOESS Preparatory Project (NPP) Science Overview

Science.gov (United States)

Butler, James J.

2011-01-01

NPP Instruments are: (1) well understood thanks to instrument comprehensive test, characterization and calibration programs. (2) Government team ready for October 25 launch followed by instrument activation and Intensive Calibration/Validation (ICV). NPP Data Products preliminary work includes: (1) JPSS Center for Satellite Applications and Research (STAR) team ready to support NPP ICV and operational data products. (2) NASA NPP science team ready to support NPP ICV and EOS data continuity.

Dimethylamine as a Replacement for Ammonia Dosing in the Secondary Circuit of an Advanced Gas-Cooled Reactor (AGR) Power Station

International Nuclear Information System (INIS)

Armstrong, C.; Mitchell, M.; Bull, A.; Quirk, G.P.; Rudge, A.

2012-09-01

Increasing flow resistance observed over recent years within the helical once-through boilers in the four Advanced Gas-Cooled Reactors (AGRs) at Hartlepool and Heysham 1 Power stations have reduced boiler performance, resulting in reductions in feedwater flow, steam temperatures, power output and the need to carry out periodic chemical cleaning. The root cause is believed to be the development of magnetite deposits with high flow impedance in the 9%Cr evaporator section of the boiler tubing. To prevent continued increases in boiler flow resistance, dimethylamine is being trialled, in one of the four affected units, as a replacement to the conventional ammonia dosing. Dimethylamine increases the pH at temperature around the secondary circuit and, based on full scale boiler rig simulations, is expected to reduce iron transport and prevent flow resistance increases within the evaporator section of the boiler. The dimethylamine plant trial commenced in January 2011 and is ongoing. The feedwater concentration of dimethylamine has been increased progressively towards a final target value of 900 μg kg -1 and its effect on iron transport and boiler pressure loss is being closely monitored. The high steam temperatures (>500 deg. C) of the secondary circuit lead to some decomposition of dimethylamine, which is being carefully monitored at various locations around the circuit. The decomposition products identified with dimethylamine dosing include ammonia, methylamine, formic acid, carbon dioxide and, as yet, unidentified neutral organic species. The effect of dimethylamine dosing on iron transport, boiler pressure drops and its decomposition behaviour around the secondary circuit during the plant trial will be presented in this paper. (authors)

Corrosion and indices of operating reliability of steam-water circuits of foreign NPP

International Nuclear Information System (INIS)

Martynova, O.I.

1983-01-01

Corrosion failures in circuits of foreign NPPs are considered. According to American statistics there are more corrosion failures in two-circuit NPPs than in NPPs with one circuit. Steam generators mostly suffer from ''corrosion denting''. Lately pitting corrosion becomes a potentially serious problem. Steam generator vertical tubes are maiply subjected to this corrosion type. Attention is drawn to intercrystalline corrosion. The causes of corrosion are described. The problem of optimization of structural materials is discussed to reduce corrosion failures as well as other methods of decreasing corrosion failures. Organization of nondestructive testing, increased requirements to water and steam purity are of great importance

Analogy for Drude's Free Electron Model to Promote Students' Understanding of Electric Circuits in Lower Secondary School

Science.gov (United States)

de Almeida, Maria José B. M.; Salvador, Andreia; Costa, Maria Margarida R. R.

2014-01-01

Aiming at a deep understanding of some basic concepts of electric circuits in lower secondary schools, this work introduces an analogy between the behavior of children playing in a school yard with a central lake, subject to different conditions, rules, and stimuli, and Drude's free electron model of metals. Using this analogy from the first…

Safety reassessment of the Paks NPP (the AGNES project)

Energy Technology Data Exchange (ETDEWEB)

Gado, J [Hungarian Academy of Sciences, Budapest (Hungary). Central Research Inst. for Physics; Bajsz, J; Cserhati, A; Elter, J [Paksi Atomeroemue Vallalat, Paks (Hungary); Hollo, E [Energiagazdalkodasi Intezet, Budapest (Hungary); Kovacs, K [EROTERV Engineering and Contractor Co (Hungary); Maroti, L [Hungarian Academy of Sciences, Budapest (Hungary). Central Research Inst. for Physics; Miko, S [Paksi Atomeroemue Vallalat, Paks (Hungary); Techy, Z [Energiagazdalkodasi Intezet, Budapest (Hungary); Vidovszky, I [Hungarian Academy of Sciences, Budapest (Hungary). Central Research Inst. for Physics

1996-12-31

The reassessment of the Paks NPP safety according to internationally recognized criteria of the Advanced General and New Evaluation of Safety (AGNES) project is outlined. The Paks NPP consists of four WWER-440/V-213 units. The following groups of analysis have been performed: system analysis and description; analysis of design basis accidents; severe accidents analysis; level 1 probabilistic safety analysis. Postulated accidents (PA) and Anticipated Operational Occurrences (AOO) are estimated in detail for the following initiating events: increase/decrease in secondary heat removal; decrease in primary coolant inventory; increase/decrease of reactor coolant inventory; reactivity and power distribution anomalies; analysis of transients with the failure of reactor scram (ATWS); pressurized thermal shock analyses. Severe accident analysis was made for the accidents on in-vessel phase and containment phase, for radioactive release and for accident management.

Safety reassessment of the Paks NPP (the AGNES project)

International Nuclear Information System (INIS)

Gado, J.; Hollo, E.; Kovacs, K.; Maroti, L.; Techy, Z.; Vidovszky, I.

1995-01-01

The reassessment of the Paks NPP safety according to internationally recognized criteria of the Advanced General and New Evaluation of Safety (AGNES) project is outlined. The Paks NPP consists of four WWER-440/V-213 units. The following groups of analysis have been performed: system analysis and description; analysis of design basis accidents; severe accidents analysis; level 1 probabilistic safety analysis. Postulated accidents (PA) and Anticipated Operational Occurrences (AOO) are estimated in detail for the following initiating events: increase/decrease in secondary heat removal; decrease in primary coolant inventory; increase/decrease of reactor coolant inventory; reactivity and power distribution anomalies; analysis of transients with the failure of reactor scram (ATWS); pressurized thermal shock analyses. Severe accident analysis was made for the accidents on in-vessel phase and containment phase, for radioactive release and for accident management

NPP life management (abstracts)

International Nuclear Information System (INIS)

Litvinskij, L.L.; Barbashev, S.V.

2002-01-01

Abstracts of the papers presented at the International conference of the Ukrainian Nuclear Society 'NPP Life Management'. The following problems are considered: modernization of the NPP; NPP life management; waste and spent nuclear fuel management; decommissioning issues; control systems (including radiation and ecological control systems); information and control systems; legal and regulatory framework. State nuclear regulatory control; PR in nuclear power; training of personnel; economics of nuclear power engineering

Nuclear power plant V-1

International Nuclear Information System (INIS)

1998-01-01

The nuclear power plant Bohunice V -1 is briefly described. This NPP consists from two reactor units. Their main time characteristics are (Reactor Unit 1, Reactor Unit 2): beginning of construction - 24 April 1972; first controlled reactor power - 27 November 1978, 15 March 1980; connection to the grid - 17 December 1978, 26 March 1980; commercial operation - 1 April 1980, 7 January 1981. This leaflet contains: NPP V-1 construction; Major technological equipment (Primary circuit: Nuclear reactor [WWER 440 V230 type reactor];Steam generator; Reactor Coolant Pumps; Primary Circuit Auxiliary Systems. Secondary circuit: Turbine generators, Nuclear power plant electrical equipment; power plant control) and technical data

Analogy for Drude’s free electron model to promote students’ understanding of electric circuits in lower secondary school

Directory of Open Access Journals (Sweden)

Maria José BM de Almeida

2014-09-01

Full Text Available Aiming at a deep understanding of some basic concepts of electric circuits in lower secondary schools, this work introduces an analogy between the behavior of children playing in a school yard with a central lake, subject to different conditions, rules, and stimuli, and Drude’s free electron model of metals. Using this analogy from the first school contacts with electric phenomena, one can promote students’ understanding of concepts such as electric current, the role of generators, potential difference effects, energy transfer, open and closed circuits, resistances, and their combinations in series and parallel. One believes that through this analogy well-known previous misconceptions of young students about electric circuit behaviors can be overcome. Furthermore, students’ understanding will enable them to predict, and justify with self-constructed arguments, the behavior of different elementary circuits. The students’ predictions can be verified—as a challenge of self-produced understanding schemes—using laboratory experiments. At a preliminary stage, our previsions were confirmed through a pilot study with three classrooms of 9th level Portuguese students.

Ignition circuit for combustion engines

Energy Technology Data Exchange (ETDEWEB)

Becker, H W

1977-05-26

The invention refers to the ignition circuit for combustion engines, which are battery fed. The circuit contains a transistor and an oscillator to produce an output voltage on the secondary winding of an output transformer to supply an ignition current. The plant is controlled by an interrupter. The purpose of the invention is to form such a circuit that improved sparks for ignition are produced, on the one hand, and that on the other hand, the plant can continue to function after loss of the oscillator. The problem is solved by the battery and the secondary winding of the output transformers of the oscillator are connected via a rectifier circuit to produce a resultant total voltage with the ignition coil from the battery voltage and the rectified pulsating oscillator output.

Modeling of coherent heat and mass-exchange phenomena for a specter of primary circuit leaks in a NPP with WWER-1000 type reactor

International Nuclear Information System (INIS)

Stanev, I.; Mladenova, S.; Hadjiev, V.

2004-01-01

Subject of study are the inter-relations between the primary leak parameters, the containment pressure and the functioning of the WWER-1000/V320 plant systems. The model includes systems for normal operation and safety systems, which are actuated in the initial stage of the accident. The studied specter of primary leaks includes diameters from 10 to 60 mm. The model is based on the design features of unit 5 in NPP Kozloduy. This paper presents a fragment of the work, performed jointly by Atoma Consult Ltd and NPP Kozloduy Plc on the validation of the symptom oriented emergency operation procedures for units 5 and 6 in NPP Kozloduy. (authors)

The V-1 NPP and V-2 NPP upgrading

International Nuclear Information System (INIS)

1998-01-01

A brief account of activities in the V-1 NPP and V-2 NPP upgrading as well as maintenance carried out by the Nuclear power plants Jaslovske Bohunice in 1997 is presented. The V-1 NPP applied the so called 'Small Backfitting Programme'covering 81 points of the Czechoslovak Atomic energy Commission Decree No 5/91. Continual upgrading continued after the Backfitting Programme completion with the Safety Report and following Nuclear Regulatory Authority of Slovak Republic (NRA SR) Decrees No 1/94 and 110/94 setting spheres and procedure for adopting and implementation of measures enabling the units to operate further on. Results of expert missions, analyses and assessments of components identified by Basic Engineering became the basis for the development of the Gradual Reconstruction Programme. The Programme outputs underwent economic and probabilistic assessing their contribution to nuclear safety. This process resulted in finalizing the Gradual Reconstruction Programme which started to be implemented in 1996 and will be completed in 1999. It is implemented by the REKON consortium and covers 17 areas including Instrumentation and Control, self-consumption emergency supply, leakage monitoring, emergency core cooling system, seismic reinforcement and radioactivity localisation. Both units will reach internationally acceptable safety standards for the remaining life-time period. The V-2 NPP Upgrading and Safety Enhancement Programme includes results of activities performed in the course of last years to define all important activities leading to enhancement of nuclear safety and performance reliability and effectiveness within the plant life-time period and to establish conditions for extending the life-time of these units for 40 years. The V-2 NPP Upgrading and Safety Enhancement Programme aims to assure safe operation with a probability of the core damages less than 10 -4 /reactor · year

Hydrology and Oceanography Analysis Regarding The NPP Site Screening Process at Banten Province

International Nuclear Information System (INIS)

Yarianto-S-Budi-Susilo

2007-01-01

Regarding the NPP development in the future, it is needed to make inventory of potential site in the Java Island as well as in the outside Java Island. The NPP site inventory availability is to answer the energy demand challenge. Site screening process should be performed in accordance with the IAEA safety standard regarding the site selection, investigating several aspects related to the NPP safety (exclusion, safety and suitability factor) in the large area to obtain potential site candidates. For the site survey stage of hydrology and oceanography aspects, the analysis are more focused on the tidal phenomena along the north coastline, bathymetry, water resource, and hydrology system in the Banten Province. The method used are secondary data collection, field confirmation and internet searching. The result of the study showed that Tanjung Pujut and Tanjung Pasir are suitable based on the bathymetry and water intake facility consideration. Meanwhile Tanjung Kait and Tanjung Pasir more suitable considering tsunami aspects that may be generated by Krakatau Volcano. (author)

Secondary circuit water chemistry and related problems with SG

Energy Technology Data Exchange (ETDEWEB)

Ignatov, V; Ivanov, V [Balakovo Nuclear Power Plant (Russian Federation)

2001-07-01

Necessity for SG feed water and blowdown systems modernization Balakovo NPP steam generators PGV-1000M was identified at Units with VVER-1000 during commissioning separational, thermo-hydraulic and thermo-chemical testings. It was discovered, that in zone of 'hot' header coolant salt concentration (concentration of dissolved salts) was almost 2 times more, than salt concentration in blowdown water. A number of chemical testings was performed to investigate and optimize salts distribution in water volume of PGV-1000. (R.P.)

Secondary circuit water chemistry and related problems with SG

International Nuclear Information System (INIS)

Ignatov, V.; Ivanov, V.

2001-01-01

Necessity for SG feed water and blowdown systems modernization Balakovo NPP steam generators PGV-1000M was identified at Units with VVER-1000 during commissioning separational, thermo-hydraulic and thermo-chemical testings. It was discovered, that in zone of 'hot' header coolant salt concentration (concentration of dissolved salts) was almost 2 times more, than salt concentration in blowdown water. A number of chemical testings was performed to investigate and optimize salts distribution in water volume of PGV-1000. (R.P.)

NPP Decommissioning: the concept; state of activities

International Nuclear Information System (INIS)

Nemytov, S.; Zimin, V.

2001-01-01

The main principles of NPP decommissioning concept in Russia are given. The conditions with fulfillment of works on NPP unit pre-decommissioning and decommissioning including: development of the normative documentation, creation of special fund for financing NPP decommissioning activities, deriving the Gosatomnadzor license for decommissioning of shut down NPP units, development of the equipment and technologies for waste and spent fuel management are presented. The decommissioning cost and labour intensity of one WWER-440 unit are shown. The practical works, executed on shut down units at Beloyarsk NPP (Unit1 and 2) and Novo Voronezh NPP (Unit 1 and 2) are outlined

New equivalent lumped electrical circuit for piezoelectric transformers.

Science.gov (United States)

Gonnard, Paul; Schmitt, P M; Brissaud, Michel

2006-04-01

A new equivalent circuit is proposed for a contour-vibration-mode piezoelectric transformer (PT). It is shown that the usual lumped equivalent circuit derived from the conventional Mason approach is not accurate. The proposed circuit, built on experimental measurements, makes an explicit difference between the elastic energies stored respectively on the primary and secondary parts. The experimental and theoretical resonance frequencies with the secondary in open or short circuit are in good agreement as well as the output "voltage-current" characteristic and the optimum efficiency working point. This circuit can be extended to various PT configurations and appears to be a useful tool for modeling electronic devices that integrate piezoelectric transformers.

Design and operating condition. Consequences for EDF NPP's chemistry

International Nuclear Information System (INIS)

Bretelle, Jean-Luc; Stutzmann, Agnes; Nordmann, Francis

2009-01-01

Since the beginning of the French nuclear programme in 1977, four major types of design have been commissioned, the fifth one being under construction (EPR). The paper points out advantages and drawbacks of chemistry choices for the primary, secondary and tertiary systems in French NPP, for each design particularity and it describes the corresponding operating conditions. Chemistry option proposals are drawn for the future of the French fleet, taking into account the material behaviour and the operation improvement. (orig.)

Limit the effects of secondary circuit water or steam piping breaks in the reactor building

International Nuclear Information System (INIS)

Nachev, N.

2001-01-01

The existing design of the WWER-1000 Model 320 does not include provisions against the local mechanical effects of pipe ruptures of the secondary system piping. This situation may lead to accidental effects beyond the design basis of the plant in case of a postulated secondary pipe rupture event. The aim of the present safety enhancement measure is to overcome this safety deficit, that means to carry out some analyses and to suggest protection measures, by which the specified design basis of the plant concerning secondary circuit design basis accidents will be assured. The systems to be considered include the main steam lines (MSL) and the main feedwater lines (MFWL) in the safety related system areas. These areas are the system portions, which are located in the reactor building (containment and room A820 outside the containment). The pipe rupture effects to be considered include the local effects, that means pipe whip impact and jet forces on the adjacent equipment and structures, as well as reaction forces due to blowdown thrust forces and pressure waves in the broken piping system. (author)

Multimedia system for the visitors' centre at the Ignalina NPP

International Nuclear Information System (INIS)

Alvers, Margareta

1999-01-01

The contents illustrated with video clips, animations, photographs, show the follwing: History of Ignalina NPP (INPP) growing; Visaginas - how the town came into being; Lake Druksiai; Development of nuclear power; Technical data of INPP; Description of INPP; Characteristic features of RBMK reactors; Reactor design; Technical parametres of RBMK-1500 reactor; Nuclear reaction and nuclear fission; Types of nuclear reactors; Circuits and systems; Radiation safety; Safety systems at the INPP; Upgrading nuclear safety at INPP following the Chernobyl accident; Safety problems at MP; Radioactive waste management in the world; RW Management at MP; Energy in Lithuania (thermal power stations, cogeneration plants, producing biogas from organic waste)

Improvement of coal focus and cooling towers of COFRENTES NPP

International Nuclear Information System (INIS)

Martinez, I.; Bogh, P.

1998-01-01

Cofrentes Nuclear Power Plant is performing a improving program of its cooling towers based on the filling revamping and cooling water circuit improvement. Furthermore, and as consequence of the acquired experience on cooling towers due to the mentioned program, Cofrentes NPP has decided to follow up with this project from a different point of view based on the thermal-hydraulic optimization of the cooling process inside the towers. This program, which is going to be carried out by Cofrentes NPP, Iberinco and Energy Planning and Power Generation (EPPG) provides an improvement on the thermal profile and of the draught inside the cooling towers by improving the water distribution in the towers active area. In order to perform such a program is needed to fulfill a test program to assure a guaranteed performance gain. In this way, Iberinco is developing a test procedure which improves the results which are obtained with the present standards used commonly by the industry. As a consequence of this program, Cofrentes is expecting to obtain a gain of 5 to 8 MWe with a revenue period of 4 to 5 months, results validated in another foreigner Plant which have developed a similar program. (Author)

NPP service life management

International Nuclear Information System (INIS)

Elagin, Yu.P.

2001-01-01

Problems of NPP service life management and service life prolongation are reviewed. Methods for the prolongation of the French NPP service life are discussed, priority directions of nuclear block service life management in regard to aging in the context of the European program of investigation into the materials aging are identified. Questions of the provision of the 60 years service life of the Mihama 1 block (Japan) and decision of the problem of the control equipment aging in Great Britain are discussed. Situation with the prolongation of licenses on the NPP operation in the USA and Spain is considered [ru

Minimum success criteria at SGTR combined with loss of secondary heat sink

International Nuclear Information System (INIS)

Parzer, I.; Petelin, S.

1993-01-01

A parametric analysis has been performed investigating minimum success criteria for the hypothetical Steam Generator Tube Rupture (SGTR) accident in a Pressurized Water Reactor (PWR) Nuclear Power Plant, combined with the total loss of secondary heat sink. The analyses have been performed by RELAP5/MOD2 and MOD3 computer codes using Krsko NPP input deck. The Krsko NPP is a 2-loop Westinghouse PWR, 640 MWe, located in Slovenia and operating from 1981. Two break sizes have been chosen for the SGTR event: 2 and 5 double-ended broken tubes have been assumed. Total loss of secondary heat sink has been assumed from the beginning of the calculation. The ways of cooling down the plant after the postulated accident have been investigated, including Bleed ampersand Feed through the primary system. The NPP Krsko Emergency Operating Procedures (EOP) have been verified for this case. Some suggestions have been made, how to improve FR-H.1 procedure (Loss of Secondary Heat Sink), to include some steps, which take into account also SGTR when it is combined with loss of secondary heat sink. Possible misinterpretations of E-0 procedure (Reactor Trip or Safety Injection) have been studied

General thermodynamic description of pollutants and preservatives in water at high temperature: application to primary and secondary circuits of power plants

International Nuclear Information System (INIS)

Alvarez, Jorge L.; Kukuljan, Juan A.; Gutkowski, Karin; Japas, Maria L.; Fernandez Prini, Roberto

1999-01-01

A formalism has been developed for the description of solubilities and other thermodynamic functions, based only on the Krichevskii function and properties of the pure solvent. This formalism is applied to pollutants of primary and secondary circuits nuclear power plants. (author)

Adjustment of the Kompleks Titan-2 monitoring computerized system at the Rovno NPP third unit

International Nuclear Information System (INIS)

Zigaev, B.P.

1987-01-01

Information signal origin and processing processes in the monitoring computerized system 'Komplex Titan-2' at the Rovno NPP third unit are considered. The system exercises control over the following production equipment parameters: the state of keys of control of lock fittings, mechanisms, regulators, reserve mechanism automatic shut-down circuit; the state of lock fittings, mechanisms, regulators, reserve mechanism automated switching on; parameter deviation from permissible values; interlock operation; protection system state; the state of autonomous units and devices

Modernization programme at Dukovany NPP

International Nuclear Information System (INIS)

Trnka, M.

2000-01-01

The main goal of each NPP is to produce electricity safely, economically and without influence to environment. For Dukovany NPP it means to upgrade all documentation and perform the Equipment Upgrading Programme. All these activities are time and money consuming and therefore the determination of priority of all items was necessary. In the presentation there are mentioned some important changes in documentation, results of PSA studies and reason for Equipment Upgrading Programme performance. It was selected the most important item from the list of Equipment Upgrading Programme the I and C upgrading. Management has decided that Dukovany NPP will become among the best NPPs with WWER type of reactor. It seems this decision is the best way how to extend lifetime of the NPP. (author)

Emergency preparedness at Ignalina NPP

International Nuclear Information System (INIS)

Kairys, A.

1998-01-01

Brief review of Ignalina NPP safety upgrading and personnel preparedness to act in cases of accidents is presented. Though great activities are performed in enhancing the plant operation safety, the Ignalina NPP management pays a lot of attention to preparedness for emergency elimination and take measures to stop emergency spreading. A new Ignalina NPP emergency preparedness plan was drawn up and became operational. It is the main document to carry out organizational, technical, medical, evacuation and other activities to protect plant personnel, population, the plant and the environment from accident consequences. Great assistance was rendered by Swedish experts in drawing this new emergency preparedness plan. The plan consists of 3 parts: general part, operative part and appendixes. The plan is applied to the Ignalina NPP personnel, Special and Fire Brigade and also to other contractor organizations personnel carrying out works at Ignalina NPP. There are set the following emergency classes: incident, emergency situation, alert, local emergency, general emergency. Separate intervention level corresponds to each emergency class. Overview of personnel training to act in case of an emergency is also presented

Does climate directly influence NPP globally?

Science.gov (United States)

Chu, Chengjin; Bartlett, Megan; Wang, Youshi; He, Fangliang; Weiner, Jacob; Chave, Jérôme; Sack, Lawren

2016-01-01

The need for rigorous analyses of climate impacts has never been more crucial. Current textbooks state that climate directly influences ecosystem annual net primary productivity (NPP), emphasizing the urgent need to monitor the impacts of climate change. A recent paper challenged this consensus, arguing, based on an analysis of NPP for 1247 woody plant communities across global climate gradients, that temperature and precipitation have negligible direct effects on NPP and only perhaps have indirect effects by constraining total stand biomass (Mtot ) and stand age (a). The authors of that study concluded that the length of the growing season (lgs ) might have a minor influence on NPP, an effect they considered not to be directly related to climate. In this article, we describe flaws that affected that study's conclusions and present novel analyses to disentangle the effects of stand variables and climate in determining NPP. We re-analyzed the same database to partition the direct and indirect effects of climate on NPP, using three approaches: maximum-likelihood model selection, independent-effects analysis, and structural equation modeling. These new analyses showed that about half of the global variation in NPP could be explained by Mtot combined with climate variables and supported strong and direct influences of climate independently of Mtot , both for NPP and for net biomass change averaged across the known lifetime of the stands (ABC = average biomass change). We show that lgs is an important climate variable, intrinsically correlated with, and contributing to mean annual temperature and precipitation (Tann and Pann ), all important climatic drivers of NPP. Our analyses provide guidance for statistical and mechanistic analyses of climate drivers of ecosystem processes for predictive modeling and provide novel evidence supporting the strong, direct role of climate in determining vegetation productivity at the global scale. © 2015 John Wiley & Sons Ltd.

The seismic reassessment Mochovce NPP

International Nuclear Information System (INIS)

Baumeister, P.

2004-01-01

The design of Mochovce NPP was based on the Novo-Voronez type WWER-440/213 reactor - twin units. Seismic characteristic of this region is characterized by very low activity. Mochovce NPP site is located on the rock soil with volcanic layer (andesit). Seismic reassessment of Mochovce NPP was done in two steps: deterministic approach up to commissioning confirmed value Horizontal Peak Ground Acceleration HPGA=0.1 g and activities after commissioning as a consequence of the IAEA mission indicate higher hazard values. (author)

Ignalina NPP: living and working conditions

International Nuclear Information System (INIS)

Chiuzhas, A.

1998-01-01

The conference was devoted to discuss the social problems related with the operation of Ignalina NPP. The main topics are the following: analysis of public opinion of surrounding region of Ignalina NPP including neighbouring Daugavpils district in Latvia, environment impact evaluation of Daugavpils district, assessment of the influence of Ignalina NPP operation to the development of business in the region, investigation of problems of Visaginas town - residence of Ignalina NPP personnel. The specificity of Visaginas (former Sniechkus) is defined by the majority of non-native Lithuanians living there. Cultural transformation and political organization of the region were surveyed as well

Sustainability issues in circuit board recycling

DEFF Research Database (Denmark)

Legarth, Jens Brøbech; Alting, Leo; Baldo, Gian Luca

1995-01-01

The resource recovery and environmental impact issues of printed circuit board recycling by secondary copper smelters are discussed. Guidelines concerning material selection for circuit board manufacture and concerning the recycling processes are given to enhance recovery efficiency and to lower...

Spain in South Ukraine NPP

International Nuclear Information System (INIS)

Ibanez, M.

1994-01-01

A Technical Assistance Protocol was signed between the Governments of the GIS and the Commission of the European Union (CEU) on August 2, 1991 and this was the starting point of the TACIS program. In this article, the activities described are those related to the TACIS-92/93/94 on site technical assistance to South Ukraine NPP (SUK NPP). Within the scope of the TACIS 92 Program the CEU and the Ukrainian Authorities agreed a list of projects to be implemented at South Ukraine NPP with the aim to improve the operational safety of the plant. This part of the program is called TACIS 92 on-site activities. The total budget allocated to these projects is a MECU. The European Union ''utility'' selected to lead this program at South Ukraine NPP was UNESA and the first contract to cover our activities was signed in July 1993 between the CEU (Mr. Pablo Benavides) and UNESA (Mr. Pedro Rivero). The projects will be implemented at SUK NPP but according to the contract UNESA is ''The Consultant'' and GOSKOMATON (The Ukrainian Sate Committee on Nuclear Power Utilization) is the ''Recipient Institution''. (Author)

Selection of NPP for Kazakhstan

International Nuclear Information System (INIS)

Zhotabaev, Zh.R.

2003-01-01

Commercial NPP for Kazakhstan should to meet to several main requirements: 1). Safety operation (accident probability not more than 10 -6 1/p. year). 2). High efficiency > 40 %. 3). Possibility of use for high-temperature chemistry and hydrogen production. 4). Possibility for manufacturing of considerable part of equipment in Kazakhstan. 5). Possibility for fuel production and reprocessing in Kazakhstan. 6). Independence from existence of large water-supply sources. Comparative analysis of several NPP with different reactors (WWR-1000, Candu, BREST, VG-400; graphite molten salt reactor) shows that NPP with the graphite molten salt reactor meets to all above requirements, but hydrogen production it is possible by more complete 4-stage technology, since coolant temperature is 800 Deg. C. The principle advantage is possibility of manufacturing of main equipment and fuel in Kazakhstan that reduce the cost of NPP construction and operation

Experience with humidity monitoring and leak detection system SMU-V at the Jaslovske Bohunice V-1 NPP

International Nuclear Information System (INIS)

Macko, O.

1996-01-01

Within the paper a brief technical description of SMU-V system is presented including algorithms for measured data evaluation, assessment of experience acquired the system operation and prospective VUEZ activities aimed at the developed of systems for NPP primary circuit leak detection based on humidity monitoring. System SMU-V is used to diagnose dangerous conditions during which integrity of the pipeline could be impaired resulting in absolute humidity increase in the monitored volume. (author)

A brief overview of Ignalina NPP safety issues

International Nuclear Information System (INIS)

Almenas, K.; Ushpuras, E.

1998-01-01

A description of the safety of Ignalina NPP in a very popular form is presented. Answers to the most frequently recurring questions concerning the Ignalina NPP are provided based on recently completed international studies. Questions are like these: can a similar accident to the one that occurred in Chernobyl take place at Ignalina NPP, does the Ignalina NPP have a containment, what are the probabilities and potential consequences of accidents, etc. The brochure contains a short description of Ignalina NPP safety improvement programs

NPP Krsko decommissioning concept

International Nuclear Information System (INIS)

Novsak, M.; Fink, K.; Spiler, J.

1996-01-01

At the end of the operational lifetime of a nuclear power plant (NPP) it is necessary to take measures for the decommissioning as stated in different international regulations and also in the national Slovenian law. Based on these requirements Slovenian authorities requested the development of a site specific decommissioning plan for the NPP Krsko. In September 1995, the Nuklearna Elektrarna Krsko (NEK) developed a site specific scope and content for a decommissioning plan including the assumptions for determination of the decommissioning costs. The NEK Decommissioning Plan contains sufficient information to fulfill the decommissioning requirements identified by NRC, IAEA and OECD - NEA regulations. In this paper the activities and results of development of NEK Decommissioning Plan consisting of the development of three decommissioning strategies for the NPP Krsko and selection of the most suitable strategy based on site specific, social, technical, radiological and economic aspects, cost estimates for the strategies including the costs for construction of final disposal facilities for fuel/high level waste (fuel/HLW) and low/intermediate level waste (LLW/ILW) and scheduling of all activities necessary for the decommissioning of the NPP Krsko are presented. (author)

NPP Krsko decommissioning concept

International Nuclear Information System (INIS)

Novsak, M.; Fink, K.; Spiler, J.

1996-01-01

At the end of the operational lifetime of a nuclear power plant (NPP) it is necessary to take measures for the decommissioning as stated in different international regulations and also in the national Slovenian law. Based on these requirements Slovenian authorities requested the development of a site specific decommissioning plan for the NPP KRSKO. In September 1995, the Nuklearna Elektrarna Krsko (NEK) developed a site specific scope and content for decommissioning plan including the assumptions for determination of the decommissioning costs. The NEK Decommissioning Plan contains sufficient information to fulfill decommissioning requirements identified by NRC, IAEA and OECD - NEA regulations. In this paper the activities and the results of development of NEK Decommissioning Plan consisting of the development of three decommissioning strategies for the NPP Krsko and selection of the most suitable strategy based on site specific, social, technical, radiological and economical aspects, cost estimates for the strategies including the costs for construction of final disposal facilities for fuel/high level waste (fuel/HLW) and low/intermediate level waste (LLW/ILW) and scheduling all activities necessary for the decommissioning of the NPP KRSKO are presented. (author)

Identification of Standing Pressure Waves Sources in Primary Loops of NPP with WWER and PWR

Directory of Open Access Journals (Sweden)

K.N. Proskuriakov

2016-05-01

Full Text Available Results of measurement and calculation of Eigen frequencies of coolant pressure oscillations in primary loops of NPP are presented. The simple calculation model based on equivalence of electric circuit with elastic wave propagation in liquids and gases, which gives a sensible interpretation of standing pressure waves sources is developed. It is shown, that pressurizer manifest itself as managed Helmholtz resonator generating a number of SPW (with Eigen frequencies of steam volume, water volume and their combination with coolant volume of respiratory line.

Optimization of a primary circuit of the nuclear power plant from the vibration point of view

International Nuclear Information System (INIS)

Dupal, J.; Zeman, V.

2003-01-01

The primary circuit of the nuclear power plant (NPP) as a dynamical vibrating system can be disturbed by various excitation including earthquake or pressure pulsation generated by main circulation pumps (MCP). Especially, unpleasant pulsation vibration growth can be caused by the small differences of revolutions between main circulation pumps of the individual coolant loops. This growth corresponds to the well known beats. The paper deals with an approach to the improving and optimization of dynamical properties of the whole primary circuit system including the reactor and coolant loops under pressure pulsation. (author)

Operation Aspect of the Main Control Room of NPP

International Nuclear Information System (INIS)

Sahala M Lumbanraja

2009-01-01

The main control room of Nuclear Power Plant (NPP) is operational centre to control all of the operation activity of NPP. NPP must be operated carefully and safely. Many aspect that contributed to operation of NPP, such as man power whose operated, technology type used, ergonomic of main control room, operational management, etc. The disturbances of communication in control room must be anticipated so the high availability of NPP can be achieved. The ergonomic of the NPP control room that will be used in Indonesia must be designed suitable to anthropometric of Indonesia society. (author)

30 CFR 75.900-2 - Approved circuit schemes.

Science.gov (United States)

2010-07-01

... device installed in the main secondary circuit at the source transformer may be used to provide undervoltage protection for each circuit that receives power from that transformer. (c) One circuit breaker may... accordance with the settings listed in the tables of the National Electric Code, 1968. ...

Investigation of primary-to-secondary leakage accident on the PSB-VVER integral test facility

International Nuclear Information System (INIS)

Lipatov, I.A.; Dremin, G.I.; Galtchanskaya, S.A.; Chmal, I.I.; Moloshnikov, A.S.; Gorbunov, Y.S.; Antonova, A.I.; Elkin, I.V.

2001-01-01

The full text follows. The paper presents the main results from the test on primary-to-secondary leakage of 100 mm in equivalent diameter. The test was performed on the PSB-VVER integral test facility. PSB-VVER is a 4-loops scaled down model of primary system of NPP with VVER-1000 Russian type reactor. Volume - power scale is about 1/300 while elevation scale is 1/1. All components of the primary system of the reference NPP are modeled on PSB-VVER. Both passive (accumulators) and active (high and low pressure) ECCSs, pressurizer spray and relief circuits, feed water system and atmospheric dumping system (ADS) as well as the primary circuit gas remove emergency system are also simulated. The primary-to-secondary leakage was simulated using an external break line which connects the upper part of the hot header to SG water volume. The break line included a break nozzle (a cylindrical channel d = 5.8 mm, l/d = 10 with sharp inlet edge), quick-acting valve and two-phase mass flow rate measurement system. In addition loss of off-site power at the moment when a scram-signal is generated was assumed in the experiment. Thus the accident is to be considered as a beyond-design-basic one. The loss of off-site power results in the following: -main circulation pump shutdown; -pressurizer heaters switching off; -HPIS water cooling flow rate and number of points of water injection are reduced The study focuses on the adequacy of the associated accident management (AM) procedure developed by EDO ''GIDROPRESS'' as a General Designer of VVER-type reactors. The AM-procedure was adopted to the PSB-VVER test facility conditions using CATHARE (France) and DINAMIKA (Russia) codes analysis. The AM-procedure in PSB-VVER is as follows: after about 30 min of the onset of the accident, when the accident type and the localization of the SG affected become evident for the operator, he closes all the main steam isolation valves, inhibits the ADS actuation in the affected SG and begins to remove

Radiation ecological monitoring in NPP region

International Nuclear Information System (INIS)

Egorov, Yu.A.; Kazakov, S.V.

1985-01-01

The known principle of sanitary-hygienic regulation of NPP radiation effect on man and environment is analyzed. An ecological approach is required to optimize NPP relations with the environment and to regulate radioactivity of the NPP - environment system. The ecological approach envisages the development of standards of permissible concentrations of radioactive and chemical substances (as well as heat) in natural environment, taking into account their synergism, corresponding to ecologically permissible response reactions of biota to their effect. The ecological approach also comprises the sanitary-hygienic principle of radiation protection of man. Attention is paid to ecological monitoring in NPP region, comprising consideration of factors, affecting the environment, evaluation of the actual state of the environment, prediction of the environmental state, evaluation of the expected environmental state

Environmental impact of the NPP Krsko

International Nuclear Information System (INIS)

Novosel, N.

1996-01-01

The Ministry of Economic Affairs has for six years now been monitoring the operation of the Krsko NPP (NEK) and its impact on the environment. A bulletin titled 'NEK - Energy and Environment' is being issued every three months. It contains information on operation of the Krsko NPP for the previous three months, a graph of duration of temperature increase of water in the Sava river (delta T) in that period, an assessment of the radiological impact of Krsko NPP on the environment through an equivalent dose cumulatively throughout the calendar year, and a short current text related to Krsko NPP. The Ministry of Economic Affairs organizes a press conference on every issue of the bulletin, as an attempt of introducing this subject to the media and to the public. This paper contains a review of information given in the NEK bulletin from 1990 to 1995 with a special emphasis on the contribution of the Krsko NPP to the artificially caused radiation on the border between the Republic of croatia and the Republic of Slovenia. (author)

NPP Prevlaka - Preparation of construction

International Nuclear Information System (INIS)

Bojic, K.

1984-01-01

On the basis of study 'Optimal electricity generation structure till the year 2000' production of 3 x 500 MWe in nuclear power plants has been anticipated. Second Croatian-Slovenian NPP project will be based on the same principles the first one (NPP Krsko) was based on. Preconstruction investigation studies are performed at site Prevlaka on river Sava downstream of Zagreb. Licensing procedure has started with republic Urban countryside planning activities. Preconstruction activities are planned to be finished by the end of 1986. while the construction is expected to start during 1987. Parallel to investigation studies for NPP Prevlaka, evaluation of nuclear technology and reactor type is planned to be made. (author)

Study on application of ethanolamine in NPP secondary water treatment

International Nuclear Information System (INIS)

Wang Lin; Xie Yang; Cui Huaiming

2013-01-01

Ethanolamine (ETA) is an organic amine which has stronger alkalinity and lower volatility than ammonia. The paper analyzes the influence of ETA used in the secondary system and calculates its distributing status at the different nodes of the secondary system. The study shows that ETA can enhance the pH value in liquid phase of vapor-liquid two phase regions, effectively inhibit the flow-accelerated corrosion, reduce the corrosion rate of the secondary system materials and improve the economy of the in-service nuclear power plants. It is concluded that ETA as a pH additive to the secondary side of pressurized water reactor is completely viable. (authors)

Seismic characterization of the NPP Krsko site

International Nuclear Information System (INIS)

Obreza, J.

2000-01-01

The goal of NPP Krsko PSA Project Update was the inclusion of plant changes (i.e. configuration/operational related) through the period January 1, 1993 till the OUTAGE99 (April 1999) into the integrated Internal/External Level 1/Level 2 NPP Krsko PSA RISK SPECTRUM model. NPP Krsko is located on seismotectonic plate. Highest earthquake was recorded in 1917 with magnitude 5.8 at a distance of 7-9 km. Site (founded) on Pliocene sediments which are as deep as several hundred meters. No surface faulting at the Krsko site has been observed and thus it is not to be expected. NPP Krsko is equipped with seismic instrumentation, which allows it to complete OBE (SSE). The seismic PSA successfully showed high seismic margin at Krsko plant. NPP Krsko seismic design is based on US regulations and standards

Radiological characterisation on V1 NPP technological systems and buildings - Contamination

International Nuclear Information System (INIS)

Hanzel, Richard; Rapant, Tibor; Svitek, Jaroslav

2012-01-01

: average dose rate, maximum dose rate, average surface contamination of floor and walls and possible identified higher local surface contamination. In the scope of the project, more than 3400 direct dose rates measurements, 1450 direct surface contamination measurements, 1200 laboratory alpha/beta/gamma analysis of outer surfaces, 560 sample analysis of primary circuit technological equipment inner surface, 20 in situ gamma spectrometric measurements and 15 sample analysis of concrete drilling cores, have been performed. Final list of RNV included 8 vectors for contamination. Radiological data of individual items in DDB have been used for determination of total radiological inventory of V1 NPP. (authors)

Some problems of NPP personnel training

International Nuclear Information System (INIS)

Vajshnis, P.P.; Kumkov, L.P.; Omel'chuk, V.V.

1984-01-01

Shortcomings of NPP personnel training are discussed. Development of full-scale training systems is necessary for qualitative training operative personnel. Primary problems that should be necessarily solved for ensuring effective training NPP personnel are considered

An algorithm for the determination of emergency process parameters at water-into-sodium leaks in the BN-800 NPP steam generator

International Nuclear Information System (INIS)

Poplavsky, V.M.; Baklushin, R.P.

1990-01-01

The paper presents calculation relationships for the determination of parameters characterizing a sodium circuit state under water-into-sodium leak emergency conditions (mass of water penetrating into sodium, the leak size, amount of impurities in coolant, the size of expected heat-exchange surface damage). An approximation of some parameters as applied to the BN-800 NPP steam generator is presented. (author). 1 ref., 2 figs

Survey of Water Chemistry and Corrosion of NPP

Energy Technology Data Exchange (ETDEWEB)

Jung, Ki Sok; Hong, Bong Geon

2008-06-15

Status of water chemistry of nuclear power plant and materials corrosion has been surveyed. For PWR, system chemistry of primary coolant and secondary coolant as well as the related corrosion of materials was surveyed. For BWR, system chemistry as whole has been surveyed with its accompanying corrosion problems. Radiolysis of coolant water and activation of corrosion products also was surveyed. Future NPP such as supercritical water cooled reactor and fusion reactor has also been surveyed for their water chemistry and corrosion problems. As a result, proposal for some research items has been suggested. Some related corrosion research techniques and electrochemical fundamentals are also presented.

Survey of Water Chemistry and Corrosion of NPP

International Nuclear Information System (INIS)

Jung, Ki Sok; Hong, Bong Geon

2008-06-01

Status of water chemistry of nuclear power plant and materials corrosion has been surveyed. For PWR, system chemistry of primary coolant and secondary coolant as well as the related corrosion of materials was surveyed. For BWR, system chemistry as whole has been surveyed with its accompanying corrosion problems. Radiolysis of coolant water and activation of corrosion products also was surveyed. Future NPP such as supercritical water cooled reactor and fusion reactor has also been surveyed for their water chemistry and corrosion problems. As a result, proposal for some research items has been suggested. Some related corrosion research techniques and electrochemical fundamentals are also presented

Fuel leak testing performance at NPP Jaslovske Bohunice

International Nuclear Information System (INIS)

Slugen, V.; Krnac, S.; Smiesko, I.

1995-01-01

The NPP Bohunice VVER-440 fuel leak testing experience are relatively extensive in comparison with other VVER-440 users. As the first Europe NPP was adapted Siemens (KWU) in core-sipping equipment to VVER-440 units and since this time were have done these tests also for NPP Paks (Hungary) and NPP Dukovany (Czech Republic). The occurrence of leaking fuel assemblies in NPP is in the last 5 years relatively stabilised and low. A significant difference can be observed between type V-230 (31 leaks) and type V-213 (1 leak). None of of the indicated leaking fuel assemblies has been investigated in the hot cell. Therefore cannot be confirm the effective causes of leak occurrence. Nevertheless, the fuel failure rate and the performance of leak testing in NPP Bohunice are comparable to the world standard at PWR's. 1 tab., 2 figs., 3 refs

Fuel leak testing performance at NPP Jaslovske Bohunice

Energy Technology Data Exchange (ETDEWEB)

Slugen, V; Krnac, S [Slovak Technical Univ., Bratislava (Slovakia); Smiesko, I [Nuclear Powr Plant EBO, Jaslovske Bohuce (Slovakia)

1996-12-31

The NPP Bohunice VVER-440 fuel leak testing experience are relatively extensive in comparison with other VVER-440 users. As the first Europe NPP was adapted Siemens (KWU) in core-sipping equipment to VVER-440 units and since this time were have done these tests also for NPP Paks (Hungary) and NPP Dukovany (Czech Republic). The occurrence of leaking fuel assemblies in NPP is in the last 5 years relatively stabilised and low. A significant difference can be observed between type V-230 (31 leaks) and type V-213 (1 leak). None of of the indicated leaking fuel assemblies has been investigated in the hot cell. Therefore cannot be confirm the effective causes of leak occurrence. Nevertheless, the fuel failure rate and the performance of leak testing in NPP Bohunice are comparable to the world standard at PWR`s. 1 tab., 2 figs., 3 refs.

Preparation for Ignalina NPP decommissioning

International Nuclear Information System (INIS)

Medeliene, D.

2004-01-01

Latest developments of atomic energy in Lithuania, works done to prepare Ignalina NPP for final shutdown and decommissioning are described. Information on decommissioning program for Ignalina NPP unit 1, decommissioning method, stages and funding is presented. Other topics: radiation protection, radioactive waste management and disposal. Key facts related to nuclear energy in Lithuania are listed

Water quality control program in experimental circuits

International Nuclear Information System (INIS)

Cegalla, Miriam A.

1996-01-01

The Water Quality Control Program of the Experimental Circuits visualizes studying the water chemistry of the cooling in the primary and secondary circuits, monitoring the corrosion of the systems and studying the mechanism of the corrosion products transport in the systems. (author)

Safety assessment and improvement of Ignalina NPP against downcomer ruptures outside Accident Localisation System

International Nuclear Information System (INIS)

Rimkevicius, S.; Urbonavicius, E.

2002-01-01

Accident Localisation System (ALS) of Ignalina NPP is a pressure suppression type confinement, designed to prevent the release of contaminated steam-water mixture to the environment in case of Loss-of-Coolant Accident (LOCA). One of the peculiarities of Ignalina NPP with RBMK-1500 reactors is that not all of the reactor coolant circuit is enclosed within ALS. Some part of downcomers, that connect Drum Separator (DS) and suction header of main circulation pump is located outside ALS. In case of downcomer rupture in DS compartment the discharge is not confined, but flows to the environment through the safety panels installed in the ceiling of DS compartments. Numerous safety analyses were performed to assess the safety of Ignalina NPP against downcomer break outside ALS, and results were used for different applications in order to improve the safety of the plant. This paper presents the overview of the performed analyses, recommendations raised and safety improvements made to enhance the safety level of NPP. One of the applications is to present the recommendations for safety improvement if maximal allowable pressure limits are exceeded. The calculations results demonstrate that in the case of two downcomers rupture in drum separators compartment the maximum permissible pressure in the reactor hall could be exceeded. The knock-out panels from the reactor hall to the environment were recommended and installed for reactor hall overpressure protection. The evaluation of the drainage system efficiency from DS compartments was performed. In this case the especial attention was paid to analyse the water collection and drainage system behaviour in long term after postulated breaks. The analysis results showed that the modernization of the drainage system prevents the accumulation of the released water in the compartments even in the case of two downcomer pipes ruptures, and decreases the release of radioactive fission products (FP) to the environment.(author)

Krsko NPP Periodic Safety Review program

International Nuclear Information System (INIS)

Basic, I.; Spiler, J.; Novsak, M.

2001-01-01

The need for conducting a Periodic Safety Review for the Krsko NPP has been clearly recognized both by the NEK and the regulator (SNSA). The PSR would be highly desirable both in the light of current trends in safety oversight practices and because of many benefits it is capable to provide. On January 11, 2001 the SNSA issued a decision requesting the Krsko NPP to prepare a program and determine a schedule for the implementation of the program for 'Periodic Safety Review of NPP Krsko'. The program, which is required to be in accordance with the IAEA safety philosophy and with the EU practice, was submitted for the approval to the SNSA by the end of March 2001. The paper summarizes Krsko NPP Periodic Safety Review Program [1] including implemented SNSA and IAEA Expert Mission comments.(author)

Financial and organizational models of NPP construction projects

International Nuclear Information System (INIS)

Ivanov, Timur

2010-01-01

The recent evolution of financial and organizational models of NPP projects can be truly reputed to open a new page of the world market of NPP construction. The definition of the concrete model is based mostly on specific cooperation backgrounds and current terms and conditions under which the particular NPP project is being evolved. In this article the most commonly known strategies and schemes of financing structuring for export NPP construction projects are scrutinized. Special attention is paid to the analysis of BOO/BOT models which are based on the public-private partnership. Most BOO/BOT projects in the power sector has Power Purchase Agreements (PPA) as an integral part of them. The PPA key principles are studied here as well. The flexibility and adaptability of the public-private partnership models for financing and organization of the NPP projects contributes substantially to the competitiveness of the NPP projects especially under current economic conditions. (orig.)

External flood probabilistic safety analysis of a coastal NPP

International Nuclear Information System (INIS)

Pisharady, Ajai S.; Chakraborty, M.K.; Acharya, Sourav; Roshan, A.D.; Bishnoi, L.R.

2015-01-01

External events pose a definitive challenge to safety of NPP, solely due to their ability to induce common cause failures. Flooding incidents at Le Blayais NPP, France, Fort Calhoun NPP, USA and Fukushima Daiichi have pointed to the importance of external flooding as an important contributor to NPP risk. A methodology developed for external flood PSA of a coastal NPP vulnerable to flooding due to tsunami, cyclonic storm and intense local precipitation is presented in this paper. Different tasks for EFPSA has been identified along with general approach for completing each task

Predisposal of Radioactive Waste from NPP 1000 MWe

International Nuclear Information System (INIS)

Suryantoro

2007-01-01

Predisposal of radioactive waste from NPP 1000 MW which was planned to be operated in 2016 has been conducted. In this study NPP applying PWR type was assumed. This assessment comprises all aspects of radioactive waste coming from NPP. One through cycle was chosen consequently no reprocessing step will be conducted. The assessment shows that technologically all radioactive waste treatment process rising from NPP operation has similarities to the existing radioactive waste process conducted by RWI which has lower scale of waste amount. (author)

Operation safety at Ignalina NPP

International Nuclear Information System (INIS)

Zheltobriukh, G.

1999-01-01

An improvement of operational safety at Ignalina NPP covers: improvement of management structure and safety culture; symptom-based emergency operating procedures; staff training and full scope simulator; program of components ageing; metal inspection; improvement of fire safety. The first plan of Ignalina NPP Safety culture development for 1997 purposed to the SAR recommendation implementation was prepared and approved by the General Director

Treatment of NPP wastes using vitrification

International Nuclear Information System (INIS)

Sobolev, I.A.; Lifanov, F.A.; Stefanovsky, S.V.; Kobelev, A.P.; Savkin, A.E.; Kornev, V.I.

1998-01-01

Glass-based materials to immobilize various liquid and solid radioactive wastes generated at nuclear power plants (NPP) were designed. Glassy waste forms can be produced using electric melting including a cold crucible melting. Leach rate of cesium was found to be 10 -5 -10 -6 g/(cm 2 day) (IAEA technique). Volume reduction factor after vitrification reached 4-5. Various technologies for NPP waste vitrification were developed. Direct vitrification means feeding of source waste into the melter with formation of glassy waste form to be disposed. Joule heated ceramic melter, and cold crucible were tested. Process variables at treatment of Kursk, Chernobyl (RBMK), Kalinin, Novovoronezh (VVER) NPP wastes were determined. The most promising melter was found to be the cold crucible. Pilot plant based on the cold crucibles has been designed and constructed. Solid burnable NPP wastes are incinerated and slags are incorporated in glass. (author)

NPP electrical price and tariff in the world

International Nuclear Information System (INIS)

Mochamad Nasrullah and Sriyana

2010-01-01

Construction of a Nuclear Power Plant (NPP) is always become a controversial issue. Nuclear utility and other party which support the NPP present a calculation of NPP electricity cost too optimistic. However for utility and other party that contra to nuclear present a calculation of NPP electricity cost too pessimistic. This study present to reduce the controversy of nuclear cost. In this study, capital cost (Engineering Procurement Construction, EPC) was taken from Asian, America and Europe, operating and maintenance cost uses experience data of PLN, and nuclear fuel cost uses data year of 2008 with high price, low price and average price scenario. The methodological tools used to compare electricity generation cost was LEGECOST, a program developed by IAEA (International Atomic Energy Agency), while for electricity tariff- price calculation using a program developed by PLN research and development center. With the discount rate 10%, the result shows that the cheapest electricity generation cost of NPP is less than 40 mills/kWh, and average electricity tariff was 55 mills/kWh. In the Europe countries the electricity tariff more expensive than NPP in Asia. However generating cost and electricity tariff of NPP in United Stated of America (USA) less competitive because investment cost more expensive. Generating cost and electricity tariff was different at each country depend on salary, labor wage, materials price, construction specification, regulation related to NPP and environment aspect. (author)

Individual protection of NPP personnel

International Nuclear Information System (INIS)

Koshcheev, V.S.; Gol'dshtejn, D.S.; Chetverikova, Z.S.

1983-01-01

Specific features of NPP personnel individual protection are considered, mainly with respect to maintenance and repair works on various type reactors. The major concern is given to the selection and application reglamentations of the individual protection system (IPS), employment of sanitary locks, the organization of individual protection under the conditions of a heating microclimate. The ways are specified to the development and introduction of the most effective IPS and improvement of the entire NPP personnel individual protection system with respect to providing the necessary protection effect for maintaining high working capability of the personnel and minimizing the IPS impact on human organism functional systems. The accumulated experience in the personnel individual protection can be applied during construction and operation of NPP's in CMEA member-countries [ru

Safety culture at Mochovce NPP

International Nuclear Information System (INIS)

Markus, Jozef; Feik, Karol

2002-01-01

This article presents the approach of Mochovce NPP to the Safety culture. It presents activities, which have been taken by Mochovce NPP up to date in the area of Safety culture enhancement with the aim of getting the term into the subconscious of each employee, and thus minimising the human factor impact on occurrence of operational events in all safety areas. The article furthermore presents the most essential information on how the elements characterising a continuous progress in reaching the planned Safety culture goals of the company management have been implemented at Mochovce NPP, as well as the management's efforts to get among the best nuclear power plant operators in this area and to be an example for the others. (author)

Integrity Analysis of Turbine Building for the MSLB Using GOTHIC code for Wolsong NPP Unit 2

Energy Technology Data Exchange (ETDEWEB)

Ko, Bong-Jin; Jin, Dong-Sik; Kim, Jong-Hyun; Han, Sang-Koo [ACT, Daejeon (Korea, Republic of); Choi, Hoon; Kho, Dong-Wook [KHNP-CRI, Daejeon (Korea, Republic of)

2015-05-15

A break in the piping between the steam generators and the turbine can lead to rapid loss of secondary circuit inventory. A break inside the turbine building leads to pressure differentials between different areas of the turbine building. In order to improve the environmental protection of various components within the turbine building, a wall has been erected which effectively separates the area in which these components are housed from the rest of the turbine building. Relief panels installed in the turbine building ensure that the pressure differential across the wall would be less than that required to jeopardize the wall integrity. The turbine building service wing is excluded from the scope of this analysis. It is further assumed that any doors in the heavy wall are as strong as the wall itself, with no gaps or leakage around the doors. For the full scope safety analysis of turbine building for Wolsong NPP unit 2, input decks for the various objectives, which can be read by GOTHIC 7.2a, are developed and tested for the steady state simulation. The input data files provide simplified representations of the geometric layout of the turbine building (volumes, dimensions, flow paths, doors, panels, etc.) and the performance characteristics of the various turbine building subsystems.

Integrity Analysis of Turbine Building for the MSLB Using GOTHIC code for Wolsong NPP Unit 2

International Nuclear Information System (INIS)

Ko, Bong-Jin; Jin, Dong-Sik; Kim, Jong-Hyun; Han, Sang-Koo; Choi, Hoon; Kho, Dong-Wook

2015-01-01

A break in the piping between the steam generators and the turbine can lead to rapid loss of secondary circuit inventory. A break inside the turbine building leads to pressure differentials between different areas of the turbine building. In order to improve the environmental protection of various components within the turbine building, a wall has been erected which effectively separates the area in which these components are housed from the rest of the turbine building. Relief panels installed in the turbine building ensure that the pressure differential across the wall would be less than that required to jeopardize the wall integrity. The turbine building service wing is excluded from the scope of this analysis. It is further assumed that any doors in the heavy wall are as strong as the wall itself, with no gaps or leakage around the doors. For the full scope safety analysis of turbine building for Wolsong NPP unit 2, input decks for the various objectives, which can be read by GOTHIC 7.2a, are developed and tested for the steady state simulation. The input data files provide simplified representations of the geometric layout of the turbine building (volumes, dimensions, flow paths, doors, panels, etc.) and the performance characteristics of the various turbine building subsystems

Dissemination of Knowledge about NPP Instrumentation and Control Systems

International Nuclear Information System (INIS)

Yastrebenetsky, M.

2016-01-01

Full text: Instrumentation and control (I&C) systems are the most variable part in the nuclear power plants (NPP) comparatively with any other NPP systems. This statement is connected with the wide use of computers, rapid changes in information technologies, with the appearance of new computer complex electronic components, e.g., field programmable gate arrays (FPGA) and with appropriate point of their insertion into NPP I&C life cycle. The changes in NPP I&C systems require the dissemination of the knowledge about these systems. Lessons after Fukushima accident increase necessity of these actions. The elaboration and following dissemination of this knowledge took place in different directions: • Writing and issue of three new books about NPP I&C systems for specialists and for students which were issued in Ukrainian and USA public houses (the last book was issued in 2014); • Organization of five international scientific technical conferences, devoted to NPP I&C safety problems; • Elaboration of national (Ukrainian) standards and regulations pertaining to safety important NPP I&C systems (the last standard was issued in 2015) and participation in elaboration of international standards; • Lecturing for university students, NPP specialists and I&C designers. These actions in all directions are added to IAEA activity in the area NPP I&C systems (e.g., IAEA NP-T-3.12 “Core Knowledge on I&C systems in NPP”). (author

To the choice of the regeneration system of the K-1000-68/1500 turbine plant for the NPP with a vertical-type steam generator

International Nuclear Information System (INIS)

Kuznetsov, N.M.; Piskarev, A.A.; Grinman, M.I.; Kruglikov, P.A.

1985-01-01

Several variants of the heat regeneration system for the NPP with WWER-1000 type reactors using vertical steam generator (SG) generating saturated steam at 7.2 MPa pressure and 200 deg C feed water temperature at the SG inlet are considered. The results of comparison of variants in water and steam circuits of turbine plants are greatly influenced by integral economy account, i.e. efficiency indexes account under variable conditions of power unit operation. From variants of water and steam circuits of the K-1000-68/1500 turbine plant considered preference is given to the variant with four low pressure heaters with increased up to 1.25 MPa pressure in a deacrator without high pressure heater with pumping intermediate steam superheater condensate into feedwater circuit

Probabilistic assessment of NPP safety under aircraft impact

International Nuclear Information System (INIS)

Birbraer, A.N.; Roleder, A.J.; Arhipov, S.B.

1999-01-01

Methodology of probabilistic assessment of NPP safety under aircraft impact is described below. The assessment is made taking into account not only the fact of aircraft fall onto the NPP building, but another casual parameters too, namely an aircraft class, velocity and mass, as well as point and angle of its impact with the building structure. This analysis can permit to justify the decrease of the required structure strength and dynamic loads on the NPP equipment. It can also be especially useful when assessing the safety of existing NPP. (author)

NPP Bohunice experience with ASSET services

Energy Technology Data Exchange (ETDEWEB)

Klimo, J [Bohunice NPP (Slovakia)

1997-12-31

The general description of Bohunice NPP ASSET experience history was given at the last annual workshop in 1995. In my short presentation I would like to pay attention to the progress in this area which was achieved at our NPP during the last year. (author).

NPP Bohunice experience with ASSET services

International Nuclear Information System (INIS)

Klimo, J.

1996-01-01

The general description of Bohunice NPP ASSET experience history was given at the last annual workshop in 1995. In my short presentation I would like to pay attention to the progress in this area which was achieved at our NPP during the last year. (author)

Akkuyu NPP – the first Turkish NPP. The new history of the project

International Nuclear Information System (INIS)

Tzocheva, V.

2012-01-01

An overview is given to the Turkish energy sector and nuclear power plans. The project for the construction of the first NPP in Turkey is presented. The general parameters of the Project are: CAPEX: $ 20 bln; Project design: NPP-2006; (VVER- 1200); Number of units: 4; Total capacity: 4 800 MW; Construction period: 2014 – 2023; PPA period; 15 years, fixed price terms. An account of the activities during 2011, the Worley Parsons participation are presented and a tentative project schedule is given

Inspection Qualification Centre in NPP 'Kozloduy'

International Nuclear Information System (INIS)

Mikhovski, M.

2000-01-01

In May 1999 according to the working plan of the IAEA project RER 4/020 and the decision of the NPP the Inspection Qualification Centre (IQC) has been established in order to provide examination services in the NPP. During year 1999 IVC (AEA Technology) in the framework of the DTI project provides consulting and technical assistance to the NPP, IQC, Bulgarian Academy of Sciences and Regulatory Authorities in setting up the IQC infrastructure. Now IQC work as an independent inspection body B type. The IQC activities for the period 1999-2000 are presented and further tasks are outlined

Recent activities in the field of nuclear power plant control and instrumentation in Czechoslovakia

International Nuclear Information System (INIS)

Rubek, J.

1992-01-01

The report presents a review of Czechoslovak nuclear power plants that are in operation and in the course of construction. The present state of the instrumentation of the newly built NPP's is described, and a special attention is given to work on the control of spatial power distribution in the reactor core of WWER 1000, the first unit to be installed in NPP Temelin. A project of a secondary circuit diagnostic system of this unit is described. (author). 6 refs, 1 tab

Flow accelerated corrosion and life management of the secondary circuit of the Embalse nuclear power plant

International Nuclear Information System (INIS)

Chocron, Mauricio; La Gamma, Ana M.; Fernandez, Narciso; Moyano, Ricardo; Schiersmann, Christian; Ovando, Luis E.; Sainz, Ricardo A.; Keitelman, Alberto

2003-01-01

Flow accelerated corrosion is a matter of concern in secondary circuits of nuclear power plants as well as in fossil fired plants. It contributes to the piping wall thinning and to the corrosion products transport to the steam generators. Because it is a generalized corrosion phenomena, could address to extensive failures. In that sense the plants conduct extensive programs of surveillance of piping degradation. Because the problem involves many variables like alloys, water chemistry and hydrodynamics several models have been proposed in the literature. In the present paper the variables have been organized in a spreadsheet which allows the calculation of normalized risk factors. (author)

Metamorphosis of NPP A1, V1, V2

International Nuclear Information System (INIS)

Dobak, D.; Moncekova, M.

2005-01-01

In this book the history of construction, commissioning and exploitation of NPP A1, NPP V1 and NPP V2 in Jaslovske Bohunice is presented on documentary photos. Vicinity around of these NPPs is presented, too

NPP A-1 decommissioning - Phase I

International Nuclear Information System (INIS)

Krstenik, A.; Blazek, J.

2000-01-01

Nuclear power plant A-1 with output 150 MW e , with metallic natural uranium fuelled, CO 2 cooled and heavy water moderated reactor had been prematurely finally shut down in 1977. It is necessary to mention that neither operator nor regulatory and other authorities have been prepared for the solution of such situation. During next two consecutive years after shutdown main effort of operator focused on technical and administrative activities which are described in the previous paper together with approach, condition and constraints for NPP A-1 decommissioning as well as the work and research carried out up to the development and approval of the Project for NPP A-1 decommissioning - I. phase. Subject of this paper is description of: (1) An approach to NPP A -1 decommissioning; (2) An approach to development of the project for NPP A-1 decommissioning; (3) Project - tasks, scope, objectives; (4) Mode of the Project realisation; (5) Progress achieved up to the 1999 year. (authors)

Monitoring program of surrounding of the NPP SE-EBO

International Nuclear Information System (INIS)

Dobis, L.; Kostial, J.

1997-01-01

The paper dealt with monitoring program of radiation control of surrounding of the NPP Bohunice, which has the aim: (1) to ensure the control of influence of work of the NPP Bohunice on the environment in their surrounding; (2) to ensure the back-ground for regular brief of control and supervisory organs about condition of the environment in surrounding of the NPP Bohunice; (3) to maintain the expected technical level of control of the NPP Bohunice and to exploit optimally the technical means; (4) to solicit permanently the data about the radioactivity of environment in surrounding of the NPP Bohunice for forming of files of the data; (5) to exploit purposefully the technical equipment, technical workers and to maintain their in permanent emergency and technical eligibility for the case of the breakdown; (6) to obtain permanently the files of the values for qualification of the reference levels. This program of monitoring includes the radiation control of surrounding of the NPP Bohunice, in the time of normal work of power-station's blocks, inclusively of all types of trouble-shooting and repairer works in surrounding of the NPP Bohunice, up to distance 20 km from power-station. The monitoring includes: outlets from the NPP Bohunice, monitoring of radiation characteristics in surrounding of the NPP Bohunice, (aerosols, fall-outs, soil), the links of food chains: (grass and fodder, milk, agriculture products), hydrosphere in surrounding (surface waters, drink water, bores of radiation control in complex of the NPP Bohunice, components of the hydrosphere), measurement of radiation from external sources (measurement of the dose rates, measurement of the doses [sk

Sociological investigations on Ignalina NPP and within its surroundings

International Nuclear Information System (INIS)

Chiuzhas, A.

1998-01-01

The purpose of this study was to determine the impact of Ignalina NPP and Visaginas town on the social territorial processes in the region and to reveal the impact of Ignalina NPP on the regional economic, social, demographic, political and cultural processes in the context of ecological and psychological affect. According to the results of this research three quarters of the inhabitants and the functionaries of local administration hold an opinion that operation of Ignalina NPP posses threat for the population and environment. Meanwhile they are sure that danger of Ignalina NPP is not critical. 21 - 35 % of the local administrators speak for the closure of Ignalina NPP , whereas half of Visaginas residents and three quarters of the local administrators indicate that operation of reactors is expedient. Over 90% of the population do not have sufficient information on the operation of Ignalina NPP. In the opinion of the rest Lithuanian people Ignalina NPP zone is related with the physical danger and the image of Visaginas residents as the 'others', 'strangers'. More than 90% of Ignalina NPP employees are Russian speaking, not native Lithuanians. The social relations of Visaginas with the environment are poor as a result of the situation of the town, lack of communications and cultural self isolation. (author)

Ageing management database development for PWR NPP steam generator

International Nuclear Information System (INIS)

Liu Hongyun; Xu Liangjun; Xiong Changhuai; Wang Xianyuan

2005-01-01

Steam generator (SG) is one of the key safe important equipment of NPP, which is covered by NPP aging management program. Steam Generator Aging Management Dabatase (SGAMDB) is developed to provide necessary information for SG aging management. RINPO is developing SGAMDB for domestic NPP. This system contains information and data about SG design, manufacture, operation and maintenance. The information include NPP fundamental data, SG design data, SG aging mechanism, SG operation data, SG ISI data, SG maintenance data and SG evaluation interface. The system runs at the intranet of Qinshan-1 NPP with B/S mode. It can provide information inquire and fundamental analysis for NPP SG aging team and SG aging researcher's. In addition, it provides necessary information and data for SG aging analysis and evaluation, such as all pressure test process and flaws of tubes, and collects the analysis results. (authors)

Principles of tariff determination for NPP electric power generation

International Nuclear Information System (INIS)

Ratnikov, B.E.; Gitel'man, L.D.; Artemov, Yu.N.; Fiantsev, V.S.

1988-01-01

Foundations of price-setting and order of accounting arrangement for NPP electric power are considered. NPP tariffs are established proceeding from standard costs of power generation. The standards are differentiated as to NPP groups, depending on technical, regional and natural geographic factors, taking into account the facility type, unit capacity and the number of similar NPP units. The conclusion is made that under conditions of NPP economic independence expansion and creation of prerequisites for going over to self-financing principles and also due to the qualitatively new stage of nuclear power generation development the level of efficiency, forseen by the tariffs, should be increased

Leningrad NPP and energetics of north-western Russia

International Nuclear Information System (INIS)

Belov, I.

2000-01-01

Problems of Leningrad NPP operating units modernization, their design service life finishing by year of 2010, are discussed. To assure safe operation of unit 1 investments in the amount of 30 mln. dol are necessary. Estimations suggest economic efficiency of the measures, permitting saving of 300 mln. dol worth of gas. Unfortunately, without a rise in tariff for electric power produced by NPP it seems impossible. It is recommended that substantiated tariffs are set for electric power produced by NPP starting from January, 2000. The measure is indispensable for raising investment funds intended for operating NPP modernization [ru

Overview of Cernavoda NPP training programme

International Nuclear Information System (INIS)

Valache, Cornelia

2005-01-01

Full text: The paper presents a general assessment of Cernavoda NPP personnel training programme, highlighting the role of training in human performance improvement. Cernavoda NPP Personnel Training and Authorization Department (PTAD) is the one responsible for the training of Unit 1 and 2 staff. PTAD is structured in such a manner as to support and respond to all Cernavoda NPP training, qualification and authorization requirements. The training of personnel is continuously adapted based on IAEA Guides and INPO/WANO recommendations, to keep with world standards, based on the internal and external reviews. At Cernavoda NPP the Training Concept and the Training Programmes are based on SAT - Systematic Approach to Training. The Training Concept is established on a set of training documents (RD's, SI's, IDP's), which address all the SAT phases: Analysis, Design, Development, Implementation and Evaluation. The Training Programmes are structured on the initial and continuing personnel training. Their content and goals respond to the training specific needs for each plant major job family. In order to successfully support NPP training programmes, CNPP training center has upgraded classrooms with new presentation facilities and there are plans to expand the space of the building, to develop additional operator and maintenance skills facilities. There are also a number of general areas for improvement of PTAD activity, such as operators and maintenance training, initial and continuing training of both Unit 1 and 2 staff. By responding in a timely and completely manner to all plant training requirements PTAD will help in rising human performance of Cernavoda NPP personnel, supporting the safe, efficient and cost effective production of power. (author)

Organization of monitoring of agricultural products in NPP region

International Nuclear Information System (INIS)

Panteleev, L.I.; Spirin, E.V.; Sanzharova, N.I.

1990-01-01

Problem of organizing chemical and radiation monitoring of agricultural products in NPP region is considered. Attention is paid to monitoring during NPP siting and designing, to monitoring of radioactive contamination of agricultural products under normal NPP operation, emergency situations and decommissioning

Secondary coolant circuit operation tests: steam generator feedwater supply

International Nuclear Information System (INIS)

Beroux, M.

1985-01-01

No one important accident occurred during the start-up tests of the 1300MWe P4 series, concerning the feedwater system of steam generators (SG). This communication comments on some incidents, that the tests allowed to detect very soon and which had no consequences on the operation of units: 1) Water hammer in feedwater tubes, and incidents met in the emergency steam generator water supply circuit. The technological differences between SG 900 and 1300 are pointed out, and the measures taken to prevent this problem are presented. 2) Incidents met on the emergency feedwater supply circuit of steam generators; mechanical or functional modifications involved by these incidents [fr

Belene NPP

International Nuclear Information System (INIS)

Tsvetanov, P.

1990-01-01

The book presents the main results of the studies of the Bulgarian Academy of Sciences (BAS) on the construction of a new nuclear power plant at Belene on the Danube river. The programme of the studies comprises five areas: the socio-economic and energy development and the necessity of the commissioning; a technical project and design level of the equipment (safety, radioactivity control, waste disposal and economic efficiency of the power plant); the seismic properties of the construction site; the corresponding risk and design features of the plant; the ecological impacts of the NPP and public opinion. The studies in the different areas have been carried out by independent teams, fully responsible for the formulated topical conclusions. The general opinion of the BAS voiced in the book is that the construction of Belene NPP is not sufficiently substantiated and is considered unacceptable. 94 refs., 53 fig., 56 tabs. (R.Ts.)

Study on human factor at NPP

International Nuclear Information System (INIS)

Nopp, I.

1984-01-01

Factors affecting the reliabilty of the reactor control by an NPP operator are considered on the base of the Czechoslovakia NPP operating experience. The reliability level of NPP operators depends on objective factors (conditions and regime of labour) determining the labour productivity and on subjective ones (psychological morale, physical and mental abilities and occupational level of personnel). Problems of the effect of physical and mental abilities and professional level on the reliability of personnel are considered to be the most important ones. The effect of individual abilities and specific features of the human body on changes in his occupational abilities can be estimated only to a certain degree

Perspectives of NPP personnel training in the future?

International Nuclear Information System (INIS)

Khess, R.E.

1996-01-01

Problems of the NPP personnel education are discussed during radical reorganization of the state regulation of energy production and distribution when nuclear energetics will appears in the market conditions. Effective methods of the NPP personnel training developed by the corporation GPU Nuclear are given. Potentials of the application of simulators and computerized programs for increasing the NPP personnel education efficiency are considered

The monitoring of oxygen, hydrogen and carbon in the sodium circuits of the PFR

International Nuclear Information System (INIS)

Mason, L.; Morrison, N.S.; Robertson, C.M.; Trevillion, E.A.

1984-01-01

The paper reviews the instrumentation available for monitoring oxygen, hydrogen, tritium and carbon impurity levels on the primary and secondary circuits of PFR. Circuit oxygen levels measured using electrochemical oxygen meters are compared to estimates from circuit plugging meters. The data are interpreted in the light of information from cold trap temperatures. Measurements of secondary circuit hydrogen levels using both the sodium and gas phase hydrogen detection equipment are compared to estimates of circuit hydrogen levels from plugging meters and variations in sodium phase hydrogen levels during power operation are discussed. (author)

Integrated ageing management of Atucha NPP

International Nuclear Information System (INIS)

Ranalli, Juan M.; Marchena, Martin H.; Zorrilla, Jorge R.; Antonaccio, Elvio E.; Brenna, Pablo; Yllanez, Daniela; Cruz, Gerardo Vera de la; Luraschi, Carlos; Sabransky, Mario

2013-01-01

Atucha NPP is a two PHWR unit site located in Lima, Province of Buenos Aires, 120 km north of Buenos Aires, Argentina. Until recent, the site was split in Atucha I NPP, a 350 MW pressure vessel heavy water reactor in operation since 1974; and Atucha II, a similar design reactor, twice as big as Atucha I finishing a delayed construction. With the start-up of Atucha II and aiming to integrate the management of the plants, the Utility (Nucleolectrica Argentina Sociedad Anonima - NASA) has reorganized its operation units. Within this reorganization, an Ageing Management Department has been created to cope with all ageing issues of both Atucha I and II units. The Atomic Energy Commission of Argentina (Comision Nacional de Energia Atomica - CNEA) is a state-owned R and D organization that; among other functions such as designing and building research reactors, developing uranium mining and supplying radioisotopes to the medical market; is in charge of providing support and technological update to all Argentinean NPPs. The Ageing Management Department of Atucha NPP and the Ageing Management Division of CNEA has formed a joint working group in order to set up an Integrated Ageing Management Program for Atucha NPP following IAEA guidelines. In the present work a summary of the activities, documental structure and first outputs of the Integrated Ageing Management Program of Atucha NPP is presented. (author)

Integrated Ageing Management of Atucha NPP

International Nuclear Information System (INIS)

Ranalli, J.M.; Marchena, M.H.; Zorrilla, J.R.; Sabransky, M.

2012-01-01

Atucha NPP is a two PHWR unit site located in Lima, Province of Buenos Aires, 120 km north of Buenos Aires, Argentina. Until recent, the site was split in Atucha I NPP, a 350 MW pressure vessel heavy water reactor in operation since 1974; and Atucha II, a similar design reactor twice as big as Atucha I finishing a delayed construction . With the start-up of Atucha II and aiming to integrate the management of the plants, the Utility (Nucleolectrica Argentina Sociedad Anonima - NASA) has reorganized its operation units. Within this reorganization, an Ageing Management Department has been created to cope with all ageing issues of both Atucha I and II units. The Atomic Energy Commission of Argentina (Comision Nacional de Energia Atomica - CNEA) is a state-owned R and D organization that; among other functions such as designing and building research reactors, developing uranium mining and supplying radioisotopes to the medical market; is in charge of providing support and technological update to all Argentinean NPPs. The Ageing Management Department of Atucha NPP and the Ageing Management Division of CNEA has formed a joint working group in order to set up an Integrated Ageing Management Program for Atucha NPP following IAEA guidelines. In the present work a summary of the activities, documental structure and first outputs of the Integrated Ageing Management Program of Atucha NPP is presented. (author)

Integrated ageing management of Atucha NPP

Energy Technology Data Exchange (ETDEWEB)

Ranalli, Juan M.; Marchena, Martin H.; Zorrilla, Jorge R.; Antonaccio, Elvio E.; Brenna, Pablo; Yllanez, Daniela; Cruz, Gerardo Vera de la; Luraschi, Carlos, E-mail: ranalli@cnea.gov.ar [Gerencia Coordinacion Proyectos CNEA-NASA, Comision Nacional de Energia Atomica, Buenos Aires (Argentina); Sabransky, Mario, E-mail: msabransky@na-sa.com.ar [Departamento Gestion de Envejecimiento, Central Nuclear Atucha I-II Nucleoelectrica Argentina S.A., Provincia de Buenos Aires (Argentina)

2013-07-01

Atucha NPP is a two PHWR unit site located in Lima, Province of Buenos Aires, 120 km north of Buenos Aires, Argentina. Until recent, the site was split in Atucha I NPP, a 350 MW pressure vessel heavy water reactor in operation since 1974; and Atucha II, a similar design reactor, twice as big as Atucha I finishing a delayed construction. With the start-up of Atucha II and aiming to integrate the management of the plants, the Utility (Nucleolectrica Argentina Sociedad Anonima - NASA) has reorganized its operation units. Within this reorganization, an Ageing Management Department has been created to cope with all ageing issues of both Atucha I and II units. The Atomic Energy Commission of Argentina (Comision Nacional de Energia Atomica - CNEA) is a state-owned R and D organization that; among other functions such as designing and building research reactors, developing uranium mining and supplying radioisotopes to the medical market; is in charge of providing support and technological update to all Argentinean NPPs. The Ageing Management Department of Atucha NPP and the Ageing Management Division of CNEA has formed a joint working group in order to set up an Integrated Ageing Management Program for Atucha NPP following IAEA guidelines. In the present work a summary of the activities, documental structure and first outputs of the Integrated Ageing Management Program of Atucha NPP is presented. (author)

Project No. 10 - Partial restoration of Ignalina NPP territory

International Nuclear Information System (INIS)

2000-01-01

At present Ignalina NPP territory makes a total of 2544 ha of land. Due to termination of construction activity development and due to the decision taken to shutdown unit 1 the need in such a territory fell off. For normal and safe operation of Ignalina NPP 1440 ha is enough, including 1237 ha for of Ignalina NPP administrative area and 203 ha for auxiliary objects. Ignalina NPP will have to rearrange territory, forestry that was damaged during the construction activities of the plant and to restore the damaged farmlands and to pass the rearranged forestry that belonged to the Ignalina NPP to the Ministry of Forestry. The total estimated cost of the project is about 1.042 M EURO

Main principles of NPP project ecological expert investigation

International Nuclear Information System (INIS)

Dibobes, I.K.; Revina, S.K.; Glushkov, V.P.

1983-01-01

NPP project ecological expert investigation among the other objectives is to provide implementation of standards, rules and requirements as well as government decrees and international obligations of the USSR concerning the environment protection. The expert investigation takes into consideration both environment protection, regional, resources, ecological, demographic and economic aspects. The NPP siting and the local environment and resources state are estimated as well as the structure of utilization of the latter, the expected damage to the environment due to NPP construction and the measures directed towards the optimal using of natural resources. On the basis of the presented issues suggestions about NPP projects coordination with Goskomgidromet's institutions are given [ru

Regulatory approach to NPP ageing in Bulgaria

International Nuclear Information System (INIS)

Vassilev, D.

2000-01-01

In this contribution summary information of Kozloduy NPP units is presented. The nuclear legislation, regulatory approach for managing safety aspects on NPP ageing, short term programme, complex programme PRG'97 ant other aspects of ageing management are discussed

Automatic control system at the ''Loviisa'' NPP

International Nuclear Information System (INIS)

Kukhtevich, I.V.; Mal'tsev, B.K.; Sergievskaya, E.N.

1980-01-01

Automatic control system of the Loviisa-1 NPP (Finland) is described. According to operation conditions of Finland power system the Loviisa-1 NPP must operate in the mode of week and day control of loading schedule and participate in current control of power system frequency and capacity. With provision for these requirements NPP is equipped with the all-regime system for automatic control functioning during reactor start-up, shut-down, in normal and transient regimes and in emergency situations. The automatic control system includes: a data subsystem, an automatic control subsystem, a discrete control subsystem including remote, a subsystem for reactor control and protection and overall station system of protections: control and dosimetry inside the reactor. Structures of a data-computer complex, discrete control subsystems, reactor control and protection systems, neutron flux control system, inside-reactor control system, station protection system and system for control of fuel element tightness are presented in short. Two-year experience of the NPP operation confirmed advisability of the chosen volume of automatization. The Loviisa-1 NPP operates successfully in the mode of the week and day control of supervisor schedule and current control of frequency (short-term control)

Investigation of thermohydraulic parameter variations in operating conditions of Bilibino NPP CPS cooling circuit

International Nuclear Information System (INIS)

Baranaev, Yu.D.; Koz'menkova, V.V.; Parafilo, L.M.

2015-01-01

In consequence of activities on uncovering the reasons for through faults formation in cooling tubes of reactor control and protection system (CPS) channels of Bilibino-2 reactor the conclusion is made that corrosion failure development takes place against the backdrop of periodic increase of total moisture in reactor space at transient and standby modes at top of cooling tubes of CPS channels. Formation of corrosion defects in cooling tubes of four CPS channels of unit 2 in 2011-2012 is specific factor for this plant unit and do not effect on operation of other plant units. It is pointed out that ingress of moisture into gas system of the reactor is the critical factor providing integrity of structure elements of EhPG-6 reactor core cooling system. This fact agrees nicely with the results obtained during operation AM reactor of the First NPP [ru

Increasing of prediction reliability of calcium carbonate scale formation in heat exchanger of secondary coolant circuits of thermal and nuclear power plants

International Nuclear Information System (INIS)

Tret'yakov, O.V.; Kritskij, V.G.; Styazhkin, P.S.

1991-01-01

Calcium carbonate scale formation in the secondary circuit heat exchanger of thermal and nuclear power plants is investigated. A model of calcium-carbonate scale formation providing quite reliable prediction of process running and the possibility of its control affecting the parameters of hydrochemical regime (HCR) is developed. The results can be used when designing the automatic-control system of HCR

EMAS at Doel NPP

International Nuclear Information System (INIS)

Nolan, Peter; Thoelen, Els

1998-01-01

In October 1995, Doel NPP of Electrabel, Belgium opted to seek registration under the EC Eco-management and Audit Scheme (EMAS). A comprehensive environmental management system (EMS) has been introduced and implemented, encompassing all four PWRs and the supporting departments. A critical step was to seek certification from an accredited environmental auditing body against the International Standard ISO 14001. This provided the foundation for the publicly available environmental statement required by EMAS. The complications of achieving EMAS at a time when national and international standards were being re-formulated were successfully overcome and Doel NPP passed its EMAS audit in June 1997. (author)

On psichological problem of NPP operation and control

International Nuclear Information System (INIS)

Mashin, V.A.

1994-01-01

The role of psichological factor as a reserve for increasing NPP safety connected with human factor is discussed. It is emphasized that the process of NPP personnel professional training should not be restricted by formation of a certain set of knowledge, skills and experience. It is necessary to initiate ability for constant self-developing. Control for assurance of effective interaction of the whole NPP personnel is an important problem

Bohunice V1 NPP upgrading programme

International Nuclear Information System (INIS)

Kerak, J.

2001-01-01

The paper describes whole process of Bohunice V1 NPP nuclear safety and operational reliability level increase which has been performed since units commissioning (1. unit in 1978, 2. unit in 1980), continued Small Reconstruction (1991 -1993) and finished Gradual Upgrading(1994 -2000). The main purpose is to last stage -Gradual upgrading of Bohunice V1 NPP. (author)

A study on the development of an automatic fault diagnosis system for testing NPP digital electronic circuits

International Nuclear Information System (INIS)

Kim, Dae Sik

1993-02-01

This paper describes a study on the development of an automatic fault diagnosis system for testing digital electronic circuits of nuclear power plants. Compared with the other conventional fault diagnosis systems, the system described in this paper uses Artificial Intelligence technique of model based reasoning and corroboration, which makes fault diagnosis much more efficient. In order to reduce the testing time, an optimal testing set which means a minimal testing set to determine whether or not the circuit is fault-free and to locate the faulty gate was derived. Compared with the testing using an exhaustive testing set, the testing using the optimal testing set makes fault diagnosis much more fast. Since the system diagnoses the circuit boards bases only on input and output signals, it can be further developed for on-line testing. The system was implemented on a microprocessor and was applied for Universal Circuit board testing of the Solid State protection System in nuclear power plants

Investigation of primary-to-secondary leakage accident on the PSB-VVER integral test facility

Energy Technology Data Exchange (ETDEWEB)

Lipatov, I.A.; Dremin, G.I.; Galtchanskaya, S.A.; Chmal, I.I.; Moloshnikov, A.S.; Gorbunov, Y.S.; Antonova, A.I. [Electrogorsk Research and Engineering Center, EREC, Moscow (Russian Federation); Elkin, I.V. [RRC ' ' Kurchatov Institute, Moscow (Russian Federation)

2001-07-01

The full text follows. The paper presents the main results from the test on primary-to-secondary leakage of 100 mm in equivalent diameter. The test was performed on the PSB-VVER integral test facility. PSB-VVER is a 4-loops scaled down model of primary system of NPP with VVER-1000 Russian type reactor. Volume - power scale is about 1/300 while elevation scale is 1/1. All components of the primary system of the reference NPP are modeled on PSB-VVER. Both passive (accumulators) and active (high and low pressure) ECCSs, pressurizer spray and relief circuits, feed water system and atmospheric dumping system (ADS) as well as the primary circuit gas remove emergency system are also simulated. The primary-to-secondary leakage was simulated using an external break line which connects the upper part of the hot header to SG water volume. The break line included a break nozzle (a cylindrical channel d = 5.8 mm, l/d = 10 with sharp inlet edge), quick-acting valve and two-phase mass flow rate measurement system. In addition loss of off-site power at the moment when a scram-signal is generated was assumed in the experiment. Thus the accident is to be considered as a beyond-design-basic one. The loss of off-site power results in the following: -main circulation pump shutdown; -pressurizer heaters switching off; -HPIS water cooling flow rate and number of points of water injection are reduced The study focuses on the adequacy of the associated accident management (AM) procedure developed by EDO ''GIDROPRESS'' as a General Designer of VVER-type reactors. The AM-procedure was adopted to the PSB-VVER test facility conditions using CATHARE (France) and DINAMIKA (Russia) codes analysis. The AM-procedure in PSB-VVER is as follows: after about 30 min of the onset of the accident, when the accident type and the localization of the SG affected become evident for the operator, he closes all the main steam isolation valves, inhibits the ADS actuation in the affected SG

Psychology of NPP operation safety

International Nuclear Information System (INIS)

Tret'yakov, V.P.

1993-01-01

The book is devoted to psychologic investigations into different aspects of NPP operative personnel activities. The whole set of conditions on which successful and accident-free personnel operation depends, is analysed. Based on original engineering and socio-psychologic investigations complex psychologic support for NPP personnel and a system of training and upkeep of operative personnel skills are developed. The methods proposed have undergone a practical examination and proved their efficiency. 154 refs., 12 figs., 9 tabs

Regulatory aspects of NPP safety

International Nuclear Information System (INIS)

Kastchiev, G.

1999-01-01

Extensive review of the NPP Safety is presented including tasks of Ministry of Health, Ministry of Internal Affairs, Ministry of Environment and Waters, Ministry of Defense in the field of national system for monitoring the nuclear power. In the frame of national nuclear safety legislation Bulgaria is in the process of approximation of the national legislation to that of EC. Detailed analysis of the status of regulatory body, its functions, organisation structure, responsibilities and future tasks is included. Basis for establishing the system of regulatory inspections and safety enforcement as well as intensification of inspections is described. Assessment of safety modifications is concerned with complex program for reconstruction of Units 1-4 of Kozloduy NPP, as well as for modernisation of Units 5 and 6. Qualification and licensing of the NPP personnel, Year 2000 problem, priorities and the need of international assistance are mentioned

From the chronicle of training of Dukovany NPP staff

International Nuclear Information System (INIS)

2005-01-01

The long way the Dukovany NPP had to go before the plant staff was fully qualified and skilled is described. First the training concept was prepared, then the necessary training facilities were set up, lecturers and instructors were hired and trained, training programmes and training materials were developed, and ultimately the first training course was launched in 1979. A training NPP was constructed and a full-scope simulator of the Dukovany NPP was set up. The current status of organization of NPP staff training by the CEZ utility is highlighted. (author)

Training center of Rovenskaya NPP. The experience of creation

International Nuclear Information System (INIS)

Fedorov, O.M.; Aristov, B.N.

1991-01-01

Experience in creation of a teaching-training centre at the Rovno NPP, which uses means available at unified NPPs, at most is discussed. The centre hardware complex functions include the event filing and providing for user-friendly interface with NPP technical personnel under training. The system of personnel training at the Rovno NPP teaching-training centre gives an opportunity to analyze accidents and emergency conditions more completely and carefully. The taching analysis of failures and accidents by a NPP operators using the complex of the teaching-training centre hardware sufficiently improves knowledge of particular accidents

Some results of periodical analysis of the behavior of unit 4 at the Dukovany NPP - II

International Nuclear Information System (INIS)

Jirsa, P.

1993-01-01

The results of a detailed spectral analysis of noise signals recorded at the unit 4 reactor of the Dukovany NPP during and after the start-up stage are presented. The changes in the noise source signal spectra during the start-up and in normal operation were evaluated by multidimensional autoregression analysis. The temperature dependence of the signal spectra peaks from individual detectors is described. The sources of the peaks at 27.9 and 37 Hz during normal operation were identified as standing pressure waves in the primary circuit of the reactor. 3 tabs., 23 figs., 6 refs

Assessment of realization possibility of borate-lithium water chemical regime of the PGV-100 secondary circuit for NPP with WWER-1000 type reactor

International Nuclear Information System (INIS)

Smykov, V.B.; Ermolaev, N.P.; Borzov, I.A.

1994-01-01

The theoretical and experimental assessment of chemical equilibrium reactions resulting in the weak-alkaline boric buffering water chemistry of secondary side PGV-1000 has been performed out in the article. 18 refs

Observation and modeling of NPP for Pinus elliottii plantation in subtropical China

Institute of Scientific and Technical Information of China (English)

MA ZeQing; LIU QiJing; WANG HuiMin; LI XuanRan; ZENG HuiQing; XU WenJia

2008-01-01

Based on the stem analysis of 59 individuals of Pinus elliottii in combination with tree biomass models,we calculated annual biomass increment of forest plots at Qianyanzhou Ecological Station,Chinese Academy of Sciences in subtropical China. In addition,canopy layer and community NPP were calculated based on 12 years' litter fall data. NPP of the 21-year-old forest was estimated by using the BIOME BGC model; and both measured NPP and estimated NPP were compared with flux data. Community lation between annual litter fall and annual biomass increment; and the litter fall was 1.19 times the biomass increment of living trees. From 1985 to 2005,average NPP and GPP values based on BGC simulated tree layer NPP values. NPP accounted for 30.2% (25.6%-32.9%) of GPP,while NEP accounted for 57.5% (48.1%-66.5%) of tree-layer NPP and 41.74% (37%-52%) of stand NPP. Soil respiration accounted for 77.0% of measured tree NPP and 55.9% of the measured stand NPP. NEE based on eddy covariance method was 12.97% higher than the observed NEP.

International benchmark for coupled codes and uncertainty analysis in modelling: switching-Off of one of the four operating main circulation pumps at nominal reactor power at NPP Kalinin unit 3

International Nuclear Information System (INIS)

Tereshonok, V. A.; Nikonov, S. P.; Lizorkin, M. P.; Velkov, K; Pautz, A.; Ivanov, V.

2008-01-01

The paper briefly describes the Specification of an international NEA/OECD benchmark based on measured plant data. During the commissioning tests for nominal power at NPP Kalinin Unit 3 a lot of measurements of neutron and thermo-hydraulic parameters have been carried out in the reactor pressure vessel, primary and the secondary circuits. One of the measured data sets for the transient 'Switching-off of one Main Circulation Pump (MCP) at nominal power' has been chosen to be applied for validation of coupled thermal-hydraulic and neutron-kinetic system codes and additionally for performing of uncertainty analyses as a part of the NEA/OECD Uncertainty Analysis in Modeling Benchmark. The benchmark is opened for all countries and institutions. The experimental data and the final specification with the cross section libraries will be provided to the participants from NEA/OECD only after official declaration of real participation in the benchmark and delivery of the simulated results of the transient for comparison. (Author)

Stem secondary growth of tundra shrubs

DEFF Research Database (Denmark)

Campioli, Matteo; Leblans, Niki; Michelsen, Anders

2012-01-01

Our knowledge of stem secondary growth of arctic shrubs (a key component of tundra net primary production, NPP) is very limited. Here, we investigated the impact of the physical elements of the environment on shrub secondary growth by comparing annual growth rates of model species from similar...... growth (stem apical growth, stem length, and apical growth of stem plus leaves), in some cases even with opposite responses. Thus caution should be taken when estimating the impact of the environment on shrub growth from apical growth only. Integration of our data set with the (very limited) previously...

Investigation of interfacing NPP simulators with PSCAD software

International Nuclear Information System (INIS)

Zahedi, P.

2006-01-01

This paper demonstrates a new method of interfacing a NPP simulator with the PSCAD software so that the interaction between the plant dynamics and the grid dynamics can be studied. Through this method, data extracted from NPP simulator, as an object, will be communicated to a server running PSCAD software. This paper will illustrate the use of Remote Procedure Calls (RPC) as a distributed, client-server based application used to establish a connection between NPP simulator running on UNIX server and PSCAD running on a PC. Using this method, the called procedure need not exist in the same address space as the calling procedure. Communication protocols available in the NPP simulator are used to export data from the simulator. (author)

Lessons learned from the decommissioning process affected by an accident during operation. The case of A1 NPP in Slovakia

International Nuclear Information System (INIS)

Daniska, Vladimir; Timulak, Jan; Pekar, Anton; Niznansky, Vojtech; Konecny, Ladislav

2007-01-01

Decommissioning of NPP's with standard shutdown is currently well known process. The A1 NPP in Slovakia was shutdown in 1977 after the accident in the core which caused the damage of the fuel and contamination of systems. Long period from 1977 to 2008 was needed to manage issues resulting from affecting the systems and structures of A1 NPP and the environment by the accident. Management of the damaged spent fuel, decontamination of the primary circuit and other processes generated large amounts of alpha bearing waste, mostly liquid, having sludge phases with specific physical-chemical and radiological properties. Up to 1994, the approach for eliminating the consequences of the accident was based on safety priorities. The systematic approach, which includes also the rehabilitation of the affected environment, was implemented in the period 1994-2008. The process includes also establishing of the decommissioning infrastructure, legislative and funding system with the aim to implement the standard decommissioning procedures after 2008. However, the specific aspects, especially the level and radio-nuclide composition of contamination of systems and structures will remain. For final decommissioning 2008-2033, the approach was selected which foresees four licensed phases. This approach enables proper planning and performing of individual decommissioning phases. (authors)

Licensing of the Ignalina NPP

International Nuclear Information System (INIS)

Kutas, S.

1999-01-01

Since 1991 State Nuclear Power Safety Inspectorate (VATESI) has regulated Ignalina NPP operation by issuing annual operating permits. Those have been issued following submission of specified documents by the Ignalina NPP that have been reviewed by VATESI. However, according to to the procedures that are now established in the Law on Nuclear Energy and subordinate regulations the use of nuclear energy in the Republic of Lithuania is subject to strict licensing. Therefore a decision about the licence for continued operation of unit 1 should be taken. Licence would be granted by VATESI in cooperation with the Ministry of Health, Ministry of Environment and the institutions of local authorities. Ignalina NPP presented to the VATESI safety analysis report (SAR) with other documents. SAR was made mainly by foreign experts and financed by European Bank for Reconstruction and Development (EBRD). VATESI in this process is supported by western regulators. A special project LAP - Licensing Assistance Project was launched to help VATESI perform licensing according western practices

Relap5/Mod3.1 analysis of main steam header rupture in VVER- 440/213 NPP

Energy Technology Data Exchange (ETDEWEB)

Kral, P. [Nuclear Research Inst. Rez (Switzerland)

1995-12-31

The presentation is focused on two main topics. First the applied modelling of PGV-4 steam generator for RELAP5 code are described. The results of steady-state calculation under reference conditions are compared against measured data. The problem of longitudinal subdivision of SG tubes is analysed and evaluated. Secondly, a best-estimate analysis of main steam header (MSH) rupture accident in WWER-440/213 NPP is presented. The low reliability of initiation of ESFAS signal `MSH Rupture` leads in this accident to big loss of secondary coolant, full depressurization of main steam system, extremely fast cool-down of both secondary and primary system, opening of PRZ SV-bypass valve with later liquid outflow, potential reaching of secondary criticality by failure of HPIS. 7 refs.

Relap5/Mod3.1 analysis of main steam header rupture in VVER- 440/213 NPP

Energy Technology Data Exchange (ETDEWEB)

Kral, P [Nuclear Research Inst. Rez (Switzerland)

1996-12-31

The presentation is focused on two main topics. First the applied modelling of PGV-4 steam generator for RELAP5 code are described. The results of steady-state calculation under reference conditions are compared against measured data. The problem of longitudinal subdivision of SG tubes is analysed and evaluated. Secondly, a best-estimate analysis of main steam header (MSH) rupture accident in WWER-440/213 NPP is presented. The low reliability of initiation of ESFAS signal `MSH Rupture` leads in this accident to big loss of secondary coolant, full depressurization of main steam system, extremely fast cool-down of both secondary and primary system, opening of PRZ SV-bypass valve with later liquid outflow, potential reaching of secondary criticality by failure of HPIS. 7 refs.

Relap5/Mod3.1 analysis of main steam header rupture in VVER- 440/213 NPP

International Nuclear Information System (INIS)

Kral, P.

1995-01-01

The presentation is focused on two main topics. First the applied modelling of PGV-4 steam generator for RELAP5 code are described. The results of steady-state calculation under reference conditions are compared against measured data. The problem of longitudinal subdivision of SG tubes is analysed and evaluated. Secondly, a best-estimate analysis of main steam header (MSH) rupture accident in WWER-440/213 NPP is presented. The low reliability of initiation of ESFAS signal 'MSH Rupture' leads in this accident to big loss of secondary coolant, full depressurization of main steam system, extremely fast cool-down of both secondary and primary system, opening of PRZ SV-bypass valve with later liquid outflow, potential reaching of secondary criticality by failure of HPIS

Safety Analysis Report for Ignalina NPP

International Nuclear Information System (INIS)

Negrivoda, G.

1997-01-01

In December 1994 an agreement was signed between the European Bank for Reconstruction and Development and the Republic of Lithuania for the grant of 32.86 MECU for the safety Improvement at Ignalina NPP. One of the conditions for the provision of the grant, was a requirement for an in-depth analysis of the safety level at Ignalina NPP in the scope and according to the standards acceptable for a western nuclear power plant, and to publish a Safety Analysis Report (SAR). The report should investigate and analyze any factor that could limit a safe operation of the plant, and provide recommendations for actual safety improvements. According to the agreement, Lithuania had to finalize the SAR until 31 December, 1995. The bank has also organized and financed investigation of safety at Ignalina NPP and preparation of the SAR. EBRD made an agreement with Sweden's Vattenfall, which subcontracted well-known companies from Canada, USA, Germany, etc., and also the Russian Research and Development Institute of Power Engineering (NIKIET), reactor designer of Ignalina NPP. The SAR is a very comprehensive document and contains about 8000 pages of text, diagrams and tables. The main findings of the SAR are provided in the article. A large number of discrepancies with modern rules and western practices was detected, but they were not proved to be serious enough to require reactors shutdown. Based on the recommendations of the SAR Ignalina NPP has worked out Safety Improvement Program No. 2 (SIP-2), which is planned for three years and will cost 486 MLT. (author)

Aeroflex Single Board Computers and Instrument Circuit Cards for Nuclear Environments Measuring and Monitoring

International Nuclear Information System (INIS)

Stratton, Sam; Stevenson, Dave; Magnifico, Mateo

2013-06-01

A Single Board Computer (SBC) is an entire computer including all of the required components and I/O interfaces built on a single circuit board. SBC's are used across numerous industrial, military and space flight applications. In the case of military and space implementations, SBC's employ advanced high reliability processors designed for rugged thermal, mechanical and even radiation environments. These processors, in turn, rely on equally advanced support components such as memory, interface, and digital logic. When all of these components are put together on a printed circuit card, the result is a highly reliable Single Board Computer that can perform a wide variety of tasks in very harsh environments. In the area of instrumentation, peripheral circuit cards can be developed that directly interface to the SBC and various radiation measuring devices and systems. Designers use signal conditioning and high reliability Analog to Digital Converters (ADC's) to convert the measuring device signals to digital data suitable for a microprocessor. The data can then be sent to the SBC via high speed communication protocols such as Ethernet or similar type of serial bus. Data received by the SBC can then be manipulated and processed into a form readily available to users. Recent events are causing some in the NPP industry to consider devices and systems with better radiation and temperature performance capability. Systems designed for space application are designed for the harsh environment of space which under certain conditions would be similar to what the electronics will see during a severe nuclear reactor event. The NPP industry should be considering higher reliability electronics for certain critical applications. (authors)

Research on the NPP human factors engineering operating experience review

International Nuclear Information System (INIS)

Ren Xiangchen; Miao Hongxing; Ning Zhonghe

2006-01-01

This paper addresses the importance of the human factors engineering (HFE) for the design of nuclear power plant (NPP), especially for the design of human-machine interface in the NPP. It also summarizes the scope and content of the NPP HFE. The function, scope, content and process of the NPP human factors engineering operating experience review (OER) are mainly focused on, and significantly discussed. Finally, it briefly introduces the situation of the studies on the OER in China. (authors)

Reserves of labour content reduction in NPP construction

International Nuclear Information System (INIS)

Bekerman, R.E.

1986-01-01

Specific labour contents when constructing NPP with RBMK-1000 and WWER-1000 type reactors are presented. Factors affecting labour content of NPP construction are shown. Measures aimed at labour content decrease are suggested

Reactor plant for Belene NPP completion

International Nuclear Information System (INIS)

Dragunov, Yu. G.; Ryzhov, S. B.; Ermakov, D. N.; Repin, A. I.

2004-01-01

Construction of 'Belene' NPP was started at the end of 80-ties using project U-87 with V-320 reactor plant, general designer of this plant is OKB 'Gidropress'. At the beginning of 90-ties, on completing the considerable number of deliveries and performance of civil engineering work at the site the NPP construction was suspended. Nowadays, considering the state of affairs at the site and the work performed by Bulgarian Party on preservation of the equipment delivered, the most perspective is supposed to be implementation of the following versions in completing 'Belene' NPP: for completion of Unit 1 - reactor plant VVER-1000 on the basis of V-320 reactor with the maximum use of the delivered equipment (V-320M) having the extended service life and safety improvement; for Unit 2 - advanced reactor plant VVER-1000. For the upgraded reactor plant V-230M the basic solutions and characteristics are presented, as well as the calculated justification of strength and safety analyses, design of the reactor core and fuel cycle, instrumentation and control systems, application of the 'leak-before break' in the project and implementation of safety measures. For the modernised reactor plant V-392M the main characteristics and basic changes are presented, concerning reactor pressure vessel, steam generator, reactor coolant pump set. Design of NPP with the modernized reactor plant V-320M meets the up-to-date requirements and can be licensed for completion and operation. In the design of NPP with the advanced reactor plant the basic solutions and the equipment are used that are similar to those used in standard reactor plant V-320 and new one with VVER-1000 under construction and completion in Russia, and abroad. Compliance of reactor design with the up-to-date international requirements, considering the extended service life of the main equipment, shows its rather high potential for implementation during completion of 'Belene' NPP

Water chemistry and corrosion in water-steam circuits of nuclear power plants

International Nuclear Information System (INIS)

Gardent, R.; Menet, O.

1981-01-01

The water and steam circuits of steam generators in pressurized-water nuclear power plants are described together with the mechanism of denting, and the corrosion of spacer plates that leads to cracks in tubes by constriction. The different chemical specifications applicable to the water of the secondary circuit of the generators in normal operation and on first commissioning are listed. The results obtained and the measurements of chemical values taken in operation on the water in the secondary circuits of steam generators at Fessenheim and Bugey are presented [fr

Human Resources Training Requirement on NPP Operation and Maintenance

International Nuclear Information System (INIS)

Nurlaila; Yuliastuti

2009-01-01

This paper discussed the human resources requirement on Nuclear Power Plant (NPP) operation and maintenance (O&M) phase related with the training required for O&M personnel. In addition, this paper also briefly discussed the availability of training facilities domestically include with some suggestion to develop the training facilities intended for the near future time in Indonesia. This paper was developed under the assumptions that Indonesia will build twin unit of NPP with capacity 1000 MWe for each using the turnkey contract method. The total of NPP O&M personnel were predicted about 692 peoples which consists of 42 personnel located in the head quarter and the rest 650 people work at NPP site. Up until now, Indonesia had the experience on operating and maintaining the nonnuclear power plant and several research reactors namely Kartini Reactor Yogyakarta, Triga Mark II Reactor Bandung, and GA Siwabessy Reactor Serpong. Beside that, experience on operating and maintaining the NPP in other countries would act as one of the reference to Indonesia in formulating an appropriate strategy to develop NPP human resources particularly in O&M phases. Education and training development program could be done trough the cooperation with vendor candidates. (author)

Safety culture in Ignalina NPP, regulatory view

Energy Technology Data Exchange (ETDEWEB)

Maksimovas, G [VATESI (Lithuania)

1997-09-01

The presentation describes how success on the way to a high level Safety Culture in Ignalina NPP may be achieved by daily, well motivated activities with good attitude and proper management participation, ensuring the development and proper implementation of Safety Culture principles within the activities of Operational organization of Ignalina NPP.

Safety culture in Ignalina NPP, regulatory view

International Nuclear Information System (INIS)

Maksimovas, G.

1997-01-01

The presentation describes how success on the way to a high level Safety Culture in Ignalina NPP may be achieved by daily, well motivated activities with good attitude and proper management participation, ensuring the development and proper implementation of Safety Culture principles within the activities of Operational organization of Ignalina NPP

Conference: Nuclear Safety at the Ignalina NPP - Achievements and Challenges

International Nuclear Information System (INIS)

1999-01-01

Brief description of conference which took place in Vilnius on 8-9 April 1999 is presented. The aim of the international conference is to review the work carried out, to evaluate its influence on the nuclear safety, to get acquainted with the safety system of the Ignalina NPP. On December 31, the Ignalina NPP celebrated its 15 year anniversary. During that period the Ignalina NPP has produced more than 182 billion kWh of electricity. Nuclear power is not only immense economic benefit but also a syndrome of fear of an atomic bomb and the Chernobyl accident that has formed over the years. Numerous comprehensive international studies have been performed at the Ignalina NPP. After the Chernobyl accident many steps have been taken to improve the safety of the Ignalina NPP. The introduced changes guaranteed that the void coefficient remained negative in all possible circumstances. The Ignalina NPP is intensively preparing for licensing of unit 1

Replacement of the computerized control system at NPP under operation

International Nuclear Information System (INIS)

Ermolaev, A.D.; Rakitin, I.D.

1985-01-01

Reasons and preconditions for replacement of the computerized control systems (CCS) at NPP under operation are consi-- dered. Problems dealing with management of CCS replacement, maintenance of a new CCS as well as NPP personnel training for the new system maintenance are discussed. A necessity of NPP personnel participation in these works in order to adapt CCS to requirements of NPP operation personnel and to initiate the training process is underlined. Replacement of CCS at NPP under operation is associated, as a rule, with obsolescence of old systems not ensuring growing requirements to NPP workability and safety. Principles observed at CCS replacement are reduced, mainly, to the following; maximum utilizatian of existing equipment, metal strUctures, cables, instruments, power supplies, ventilation system minimum of construction works and new communications; the least change of acting panels and boxes; changes in control desks should be introduced on the basis of the analysis of operator actions '

Validation of MCNP NPP Activation Simulations for Decommissioning Studies by Analysis of NPP Neutron Activation Foil Measurement Campaigns

Directory of Open Access Journals (Sweden)

Volmert Ben

2016-01-01

Full Text Available In this paper, an overview of the Swiss Nuclear Power Plant (NPP activation methodology is presented and the work towards its validation by in-situ NPP foil irradiation campaigns is outlined. Nuclear Research and consultancy Group (NRG in The Netherlands has been given the task of performing the corresponding neutron metrology. For this purpose, small Aluminium boxes containing a set of circular-shaped neutron activation foils have been prepared. After being irradiated for one complete reactor cycle, the sets have been successfully retrieved, followed by gamma-spectrometric measurements of the individual foils at NRG. Along with the individual activities of the foils, the reaction rates and thermal, intermediate and fast neutron fluence rates at the foil locations have been determined. These determinations include appropriate corrections for gamma self-absorption and neutron self-shielding as well as corresponding measurement uncertainties. The comparison of the NPP Monte Carlo calculations with the results of the foil measurements is done by using an individual generic MCNP model functioning as an interface and allowing the simulation of individual foil activation by predetermined neutron spectra. To summarize, the comparison between calculation and measurement serve as a sound validation of the Swiss NPP activation methodology by demonstrating a satisfying agreement between measurement and calculation. Finally, the validation offers a chance for further improvements of the existing NPP models by ensuing calibration and/or modelling optimizations for key components and structures.

Principles of Defense-in-depth philosophy applied in NPP engineering management

International Nuclear Information System (INIS)

Wu Guangwei

2011-01-01

Based on the Defense-in-depth Concept in nuclear and radiation safety, Defense-in-depth Concept for design management of Nuclear Power Plant (NPP) is developed in this paper to analyze the feasibility and importance of the application of the basic principle: Defense-in-depth concept in NPP systems performed during the design control of NPP. This paper focuses on the NPP engineering management process, and according to the analysis of such process, 5 principles of Defense-in-depth Concept applied in NPP design management are raised: (1) preventing the non-conformities of design via effective design quality management system; (2) discovering and correcting non-conformities of design quality in time via design checkup and design review meeting; (3) carrying out timely analysis and treatment against design non-conformities which have been transferred to construction phase; (4) Assessing and judging the severe non-conformities in construction phase, putting forward treatment opinions and remedies accordingly so as to avoid the existence of such non-conformities in physical construction of NPP; (5) Paying 'return-visit' and performing 'post-assessment' for NPP design to assess the designed functions and safety of NPP comprehensively. (author)

Dissolved stable noble gas measurements from primary water of Paks NPP

International Nuclear Information System (INIS)

Palcsu, L.; Molnar, M.; Szanto, Zs.; Svingor, E.; Futo, I.; Pinter, T.

2001-01-01

A sampling and measuring method of noble gases from the primary water circuit of a VVER type NPP was developed to provide relevant information about the kilter of heating rods and detailed additional information about some working parameters. The helium concentrations and 3 He/ 4 He ratios was used to estimate the content of tritium and alpha emitting isotopes of the primary water. By argon content measurements the air penetration and the required hydrazine amount for the oxygen absorption could be estimated with high accuracy. Continuous monitoring of the concentration and isotope ratios of Xe and Kr in the dissolved gas is proved to be a good tool for high sensitivity detection of small leakage of fuel elements. In case of block-3 xenon surplus was detected. The results indicate possible leakage of fuel rods.(author)

Planning and management support for NPP personnel SAT-based training programmes

International Nuclear Information System (INIS)

Ziakova, M.

1998-01-01

This paper deals with planning and management support for NPP personnel SAT based training programmes based on IAEA TC Project SLR/0/003 on upgrading NPP personnel training, with the aim of upgrading NPP safety and reliability of NPP operation and maintenance. The costs needed include both Slovak and IAEA sources. Five stages of the Project are defined: planning; organizing; motivating; implementation; control, review and accountability

Current technological trends in development of NPP systems

International Nuclear Information System (INIS)

Florescu, Gheorghe; Panaitescu, Valeriu

2010-01-01

The recent nuclear research issues look for new technologies and continuous progress in finding different and efficient solutions for sustained and upraising energy demand. The trend of increasing energy consumption and occurring of new and large consumers, especially from Asian countries, imposes finding of new means for clean, large scale and sustained energy production. NPPs availability was continuously monitored and improved; at the same time the safety of the nuclear energy production was under surveillance. The present development of the new technologies, the discoveries of new materials and development of efficient technological processes offer the opportunities for their appropriate implementation and use in the NPP system configurations and functioning/operation. The new technologies and scientific discoveries, and also the international cooperation, offer the opportunities to mitigate the actual barriers in order to cumulate and use advanced energy production, to find new energy sources and to build improved, reliable and safe power plants. The monitoring systems, intelligent sensors and SSCs, nanotechnologies and new/intelligent materials constitute the main ways for improvement of the NPP systems configuration and processes. The paper presents: - The state of the art in the level of the currently applied technologies for nuclear power systems development; - The actual technological limits that need to be over passed for improving the NPP systems ; - The main systems that need improvement and reconfiguration for development of currently operating NPPs as well as raising the operation efficiency, availability and total safety; - The actual energy production issues; - The key arguments in sustaining the R and D new NPP systems development; - Future trends in NPP development; - The limitations in industrial processes knowledge and use. Appropriate R and D in the field of NPP systems have specific characteristics that were considered in paper completion

Effect of high-temperature filtration on impurity composition in the primary circuit coolant of power units with WWER-1000 reactors

International Nuclear Information System (INIS)

Efimov, A.A.; Moskvin, L.N.; Gusev, B.A.; Leont'ev, G.G.; Nekrest'yanov, S.N.

1992-01-01

The effects of high-temperature filtration on changes in dispersive, chemical, radioisotope and phase compositions of impurities in primary circuit coolant of NPP with the WWER-1000 reactor are studied. Special filters are used for the studies. The data obtained confirm the applicability of high-temperature filtration for purification of WWER reactor water and steam separators at NPPs with RBMK reactors

Summary of NPP personnel training in Czech Republic

International Nuclear Information System (INIS)

1996-01-01

The preparation of NPP personnel is one of the most important phases of the process of construction, commissioning, operation and maintenance of nuclear power facilities. The objective is to improve personnel abilities so that they would be able to assure reliable, safe and economic operation of these facilities with high investment costs. It is the purpose of Nuclear Training Centre Brno (NTC Brno) to provide training and services which are responsive to the technological demands and emerging educational standards and criteria of the NPP and the nuclear industry. Fulfilling this purpose is a challenging task. The staff of NTC Brno, in a joint effort with NPP Dukovany and NPP Temelin, has responded to the challenge with comprehensive programs aimed at meeting customers needs. The programs are broadly based, yet flexible so that they can incorporate specific customer requirements

To question of NPP power reactor choice for Kazakhstan

International Nuclear Information System (INIS)

Batyrbekov, G.A.; Makhanov, Y.M.; Reznikova, R.A.; Sidorenco, A.V.

2004-01-01

in the regions of Republic of Kazakhstan occurs. Southern and western regions import electric power and capacity because of undeveloped circuit of networks. Moreover, power intensity of an industrial-agrarian complex of the country is limited transmission capacity of lines is insufficient; plenty of small consumers are removed from power supply lines. Thus, nuclear stations of medium and low power are the most acceptable for construction in Kazakhstan. Recommendations for the choice of maximum safe, reliable and economically competitive reactors for Kazakhstan have been made in result of the carried out projects' comparison of the power reactors according to 15 criteria of safety and economic competitiveness, with respect to condition and perspectives of Kazakhstan power complex development: Recommended power reactors of medium capacity: - P-600 - passive PWR, developed of the Westinghouse company, USA; - CANDU-6, developed by Atomic Energy of Canada, Limited (AECL), Canada. - MS-600 - Mitsubishi Company, Japan. Recommended reactors of low power: - IRIS - reactor of IV generation developed by the international corporation of 13 organizations from 7 countries; - NPP 'UNITERM' - development NIKIET, Moscow, Russia; - MRX - the Project of sea reactor MRX for civil applications, is developed by the Japanese Research Institute of Atomic Energy (JAERI). The most important advantages of recommended medium and low power reactors are given

To question of NPP power reactor choice for Kazakhstan

International Nuclear Information System (INIS)

Batyrbekov, G.A.; Makhanov, Y.M.; Reznikova, R.A.; Sidorenco, A.V.

2004-01-01

regions of Republic of Kazakhstan occurs. Southern and western regions import electric power and capacity because of undeveloped circuit of networks. Moreover, power intensity of an industrial-agrarian complex of the country is limited transmission capacity of lines is insufficient; plenty of small consumers are removed from power supply lines. Thus, nuclear stations of medium and low power are the most acceptable for construction in Kazakhstan. Recommendations for the choice of maximum safe, reliable and economically competitive reactors for Kazakhstan have been made in result of the carried out projects' comparison of the power reactors according to 15 criteria of safety and economic competitiveness, with respect to condition and perspectives of Kazakhstan power complex development: Recommended power reactors of medium capacity: - P-600 - passive PWR, developed of the Westinghouse company, USA; - CANDU-6, developed by Atomic Energy of Canada, Limited (AECL), Canada. - MS-600 - Mitsubishi Company, Japan. Recommended reactors of low power: - IRIS - reactor of IV generation developed by the international corporation of 13 organizations from 7 countries; - NPP 'UNITERM' - development NIKIET, Moscow, Russia; - MRX - the Project of sea reactor MRX for civil applications, is developed by the Japanese Research Institute of Atomic Energy (JAERI). The most important advantages of recommended medium and low power reactors are given

Emergency preparedness at Barsebaeck NPP in Sweden

International Nuclear Information System (INIS)

Olsson, R.; Lindvall, C.

1998-01-01

On-site emergency preparedness plan at Barsebaeck NPP is presented. In an emergency the responsibility of the NPP is to alarm the emergency organizations, spend all efforts to restore safe operation, assess the potential source term as to size and time, protect their own personnel, inform personnel and public. Detailed emergency procedures overview is provided

Jose Cabrera NPP severe accident management activities

International Nuclear Information System (INIS)

Blanco, J.; Almeida, P.; Saiz, J.; Sastre, J.L.; Delgado, R.

1998-01-01

To prepare a common acting plan with respect to Severe Accident Management, in 1994 was founded the severe accident management ''ad-hoc'' working group from the Spanish Westinghouse PWR Nuclear Power Plant Owners Group. In this group actively collaborated the Jose Cabrera NPP Training Centre and the Department of Nuclear Engineering of UNION FENOSA. From this moment, Jose Cabrera NPP began the planning of its specific Severe Accident Management Program, which main point are Severe Accident Management Guidelines (SAMG). To elaborate this guidelines, the Spanish translation of Westinghouse Owners Group (WOG) Severe Accident Management Guidelines were considered the reference documents. The implementation of this Guidelines to Jose Cabrera NPP started on January 1997. Once the specific guidelines have been implemented to the plant, training activities for the personnel involved in severe accident issues will be developed. To prepare the training exercises MAAP4 code will be used, and with this intention, a specific Jose Cabrera NPP MAAP-GRAAPH screen has been developed. Furthermore, a wide selection of MAAP input files for the simulation of different scenarios and accidental events is available. (Author)

Electrochemical ion exchanger in the water circuit to measure cation conductivity

International Nuclear Information System (INIS)

Bengtsson, B.; Ingemarsson, R.; Settervik, G.; Velin, A.

2010-01-01

In Ringhals NPP, more than four years of successful operation with a full-scale EDI for the recycling of steam generator blow down (SGBD) gave the inspiration to modify and 'scale down' this EDI process. This with purpose to explore the possibilities to replace the cation exchanger columns used for cation conductivity analysis, with some small and integrated electrochemical ion-exchange cells. Monitoring the cation conductivity requires the use of a small cation resin column upstream of the conductivity probe and is one of the most important analyses at power plants. However, when operating with high alkaline treatment in the steam circuit, it's connected to the disadvantage of getting the resins rapidly exhausted, with needs to be frequently replaced or regenerated. This is causing interruptions in the monitoring and giving rise to high workload for the maintenance. This paper reports about some optimization and tests of two different two-compartment electrochemical cells for the possible replacements of cation resin columns when analyzing cation conductivity in the secondary steam circuit at Ringhals NPPs. Field tests during start up condition and more than four months of steady operation together with real and simulated test for impurity influences, indicates that a ELectrical Ion Echange process (ELIX) could be successfully used to replace the resin columns in Ringhals during operating with high pH-AVT (All Volatile Treatment), using hydrazine and ammonia. Installation of an ELIX-system downstream a particle filter and upstream of a small cation resin column, will introduce additional safety and further reduce the maintenance with possible interruptions. Performance of the ELIX-process together with other chemical additives (Morpholine, ETA, MPA, DMA) and dispersants, may be further evaluated to qualify the ELIX-process as well as SGBD-EDI for wider use in nuclear applications. (author)

Conditioning the radioactive oils released from the Cernavoda NPP operation

International Nuclear Information System (INIS)

Popescu, I.; Deneanu, N.; Dulama, M.; Baboiescu, E.

2001-01-01

The radioactive oils released during the Cernavoda NPP operation are lubricating oils used in the primary circuit pumps, hydraulic oils used in the reactor charging machine, as well as, waste turbine oils. The primary cooling circuit is the main way of contamination. This waste contain variable amounts of tritium of activities up to 10 8 Bq/l and relatively small amounts of β/γ emitting radionuclides. The radioactive oils resulting of the heat transport system may contain as much as 1.8 TBq/l of tritium. At INR Pitesti, Department of Radioactive Waste Processing, studies were done concerning the radioactive oils conditioning in concrete. It was found that the minimal compression level required for disposal, of 50 MPa, was exceeded. As consequence, the conditioned waste fulfils the conditions of acceptance provided by the Radioactive Waste National Repository at Baita-Bihor. The main stages of the process are: - dosing the radioactive oil, water and NOFOX9 and NOFOX4 emulsion additives for the 220 l or 80 l barrel; - mixing these ingredients up to reaching the emulsion state; - dosing the cement and lime; - adding the enhancing silicate and shaking the mixture to get a homogeneous matrix; - closing the barrel; - conditioning the 80 l barrel within the 220 l container. The production capacity is of 5 to 8 barrels/shift

Transition cycle fuel management problems of NPP Krsko

International Nuclear Information System (INIS)

Petrovic, B.; Pevec, D.; Smuc, T.; Urli, N.

1989-01-01

Transition cycle fuel management problems are described and illustrated using results and experience attained during core reload design of NPP Krsko. Improved version of computer code package PSU-LEOPARD/Mcrac is successfully applied to NPP Krsko loading pattern design. (author)

On the NPP structural reliability

International Nuclear Information System (INIS)

Klemin, A.I.; Polyakov, E.F.

1980-01-01

Reviewed are the main statements peculiarities and possibilities of the first branch guiding technical material (GTM) ''The methods of calculation of structural reliability of NPP and its systems at the stage of projecting''. It is stated, that in GTM presented are recomendations on the calculation of reliability of such specific systems, as the system of the reactor control and protection the system of measuring instruments and automatics and safe systems. GTM are based on analytical methods of modern theory of realibility with the Use of metodology of minimal cross sections of complex systems. It is stressed, that the calculations on the proposed methods permit to calculate a wide complex of reliability parameters, reflecting separately or together prorerties of NPP dependability and maintainability. For NPP, operating by a variable schedule of leading, aditionally considered are parameters, characterizing reliability with account of the proposed regime of power change, i.e. taking into account failures, caused by decrease of the obtained power lower, than the reguired or increase of the required power higher, than the obtained

Technical and economical problems of decommissioning nuclear power plants (NPP) in Russia

International Nuclear Information System (INIS)

Vaneev, M.

2001-01-01

The introduction per new century has brought to atomic Engineering many new problems. One of them, which has got a serious urgency, we now shall consider. It is a problem of decommissioning NPP in Russia. By 2014 all maintained nowadays NPP in Russian Federation will develop the regular service life. And all of them on idea should be removed from operation. But, as we understand, in today's difficult economic conditions, to it NPP the procedure of prolongation of service life will be applied, and where it is impossible by virtue of the various reasons, the procedure of translation NPP in nuclear - safe condition and in a mode of a long storage under supervision, before acceptance of the decision about a method and way of financing of a decommissioning will be applied. Possible the following variants will be: use platforms of the old NPP for construction new NPP, or using as burial place NPP. The variant of a decommissioning up to a condition 'green grass' is represented unprofitable because of its dearness. The similar decommissioning was carried out in Japan. Was removed from operation research reactor of a type WWR. The expenses for this method of a decommissioning considerably surpass expenses for a method of a burial place NPP basically because of high cost of dismantle and transportation in long-term storehouses of the 1 contour equipment. The most urgent problem of decommissioning NPP, which developed their regular service life - is financing this final stage of a exploitation cycle of the block. I shall remind, that the financing is carried out from uniform fund of decommissioning. The formation of this fund occurs by deduction 1.3 % of cost of the put electric power to the consumers by all maintained NPP of Russia. The expenditure of this fund is carried on time on some tens years. They are spent for 3 basic stages: preparation to decommissioning NPP, long endurance under supervision, dismantle and burial the NPP equipment. Nowadays on faculty NPP MPEI

Unit Commissioning of “Belene” NPP (Bulgaria)

International Nuclear Information System (INIS)

2009-01-01

This presentations gives detailed information about the following topics about commissioning: principles of NPP commissioning; phases of NPP commissioning; organization of commissioning activities; duties and responsibilities of the parties for carrying out unit commissioning activities; responsibility and obligations of the sides during commissioning of power unit; documentation required for power unit commissioning; quality assurance for commissioning activities

Constructive approaches to the space NPP designing

International Nuclear Information System (INIS)

Eremin, A.G.; Korobkov, L.S.; Matveev, A.V.; Trukhanov, Yu.L.; Pyshko, A.P.

2000-01-01

An example of designing a space NPP intended for power supply of telecommunication satellite is considered. It is shown that the designing approach based on the introduction of a leading criterion and dividing the design problems in two independent groups (reactor with radiation shield and equipment module) permits to develop the optimal design of a space NPP [ru

Chernobyl NPP accident. Overcoming experience. Acquired lessons

International Nuclear Information System (INIS)

Nosovskij, A.V.; Vasil'chenko, V.N.; Klyuchnikov, A.A.; Prister, B.S.

2006-01-01

This book is devoted to the 20 anniversary of accident on the Chernobyl NPP unit 4. History of construction, causes of the accident and its consequences, actions for its mitigation are described. Modern situation with Chernobyl NPP decommissioning and transferring of 'Ukryttya' shelter into ecologically safe system are mentioned. The future of Chernobyl site and exclusion zone was discussed

Considerations related to Cernavoda NPP lifetime management

International Nuclear Information System (INIS)

Cojan, Mihail

2007-01-01

Cernavoda NPP, the first CANDU in Europe, is one of the original CANDU 6 plants and the first CANDU 6 producing over 706 MWe. While the first series of CANDU 6 plants (which entered service in the early 1980 s) have now reached the 2/3 of their 30 years design life, the Cernavoda NPP was put into service on the 2nd December 1996. After 10 years of operation the Plant Life Management (PLiM) Program for Cernavoda should be an increasingly important program to Utility ('CNE - Prod') in order to protect the investment and the continued success of plant operation. The goal of the paper is to present some considerations related to Cernavoda NPP lifetime management. The Plant Life Management Program, known as PLiM Program is concerned with the analysis of technical limits of the safe operation - from the point of view of nuclear safety - in NPP units, aiming at attaining the planned 30 years life duration and its extension to 40 or even 50 years of safe and economical operation. For the CANDU reactors the so-called PLiM and PLEX Programs are just applied. These are applied research programs that approach with priority the current practices for assessing the capability of safe operation within the limits of nuclear safety (fitness-for-service assessment). These programs also approach inspection, monitoring are prevention of degrading due to the ageing of critical systems, structures and components (CSSCs). As each nuclear plant is somewhat different in its components and systems, materials composition, procurement, construction, and operational history, directed research and development programs into materials behavior, monitoring techniques, and methods to mitigate ageing are required to support the lifetime management. Over the past 6 years, INR Pitesti (Institute for Nuclear Research - Romania) has been working on R and D Programs to support a comprehensive and integrated Cernavoda NPP Life Management Program (PLiM) that will see the Cernavoda NPP successfully and

Radiation protection in Bohunice NPP. Description of present status

International Nuclear Information System (INIS)

Dobis, L.

2001-01-01

Radiation protection (RP) at Bohunice NPP has reached the high international standard. The fact was approved by several independent international missions (OSART , WANO, WENRA, ...). A lot of modifications have been done in order to improve the standard of radiation protection. All the BSS requirements have been implemented into the plant regulations before the State Law No 290/1996 and 470/2000 came into the force. Internal audits are regularly performed at NPP in order to reveal potential deficiencies. In 2001 there were 4 such audits focused on quality assurance, software operation, LBB concept and limits and condition of safe operation. State Health Institute, the regulatory body in the radiation protection, performs the inspection at least ones a month. Good relationship with the inspectors of State Health Institute also contributes to the safe operation of the NPP. There were not any radiation accident. All anomalies or radiation events are investigated at a plant level. The results of root cause analysis and proposal of corrective actions are provided to IAEA and WANO databases for the distribution. The Radiation protection department of Bohunice NPP cooperates with the other Czech and Slovak NPPs. Regular meetings on radiation protection and lately also on emergency preparedness are organized. The cooperation is excellent. Occupational exposure is reviewed also with respect of ISOE data. Bohunice NPP (even with high dose burden caused by reconstruction of V1 NPP) can be found in the first half of world PWR speaking about the collective exposure per reactor. V2 NPP itself reaches the lowest collective exposure in the world. All doses are below the limits and kept ALARA. ALARA system has been established already in 1997 at Bohunice NPP and its results are obvious for example looking at dose results during the reconstruction works at V1 NPP. The operation of Bohunice NPP has negligible influence to its surroundings. The values of gas and liquid effluents move

Sludge lancing and IBL: Results and experiences in the Spanish NPP

International Nuclear Information System (INIS)

Montoro, E.; Pozo, C. del

2013-01-01

During the cycle of operation of the PWR plants, oxides (sludge) tanks are generated in the secondary circuit by corrosion, chemical additives, etc which are deposited onto the tubular steam generators (GVs), limiting its efficiency and service life.

Uncertainty analysis of one Main Circulation Pump trip event at the Ignalina NPP

International Nuclear Information System (INIS)

Vileiniskis, V.; Kaliatka, A.; Uspuras, E.

2004-01-01

One Main Circulation Pump (MCP) trip event is an anticipated transient with expected frequency of approximately one event per year. There were a few events when one MCP was inadvertently tripped. The throughput of the rest running pumps in the affected Main Circulation Circuit loop increased, however, the total coolant flow through the affected loop decreased. The main question arises whether this coolant flow rate is sufficient for adequate core cooling. This paper presents an investigation of one MCP trip event at the Ignalina NPP. According to international practice, the transient analysis should consist of deterministic analysis by employing best-estimate codes and uncertainty analysis. For that purpose, the plant's RELAP5 model and the GRS (Germany) System for Uncertainty and Sensitivity Analysis package (SUSA) were employed. Uncertainty analysis of flow energy loss in different parts of the Main Circulation Circuit, initial conditions and code-selected models was performed. Such analysis allows to estimate the influence of separate parameters on calculation results and to find the modelling parameters that have the largest impact on the event studied. On the basis of this analysis, recommendations for the further improvement of the model have been developed. (author)

Plant level of automated control system at a NPP with RBMK reactor

International Nuclear Information System (INIS)

Vorob'ev, V.P.; Gorbunov, V.P.; Dmitriev, V.M.; Litvin, A.S.

1987-01-01

The functional structure of plant level automated control system (ACS) at NPP with RBMK-1000 reactors, its binding with the on-line control system of higher and lower levels, as well as engineering requirements to software and recommendations on composition of hardware components, are considered. NPP ACS is an organizational-engineering system consisting of computer facilities and binding aimed at solving management, economical, organizational and physical-engineering problems to control NPP more effectively. The system carries out data acquisition, preliminary processing, analysis, transmission and representation for users to accept solutions for NPP operation by operative and management personnel. The main aim of integrated NPP ACS is the control development and increase of NPP economical efficiency, the increase of electric and heat energy production, the optimization of the production distribution between units, the development of production and economic NPP control

Modernization and safety improvement project of the NPP V-2 Jaslovske Bohunice

International Nuclear Information System (INIS)

Michal, V.; Losonsky, B.; Magdolen, J.

2000-01-01

This contribution deals with the form, present state, and results of the Nuclear Power Plants Research Institute (the Slovak acronym is VUJE - Vyskumny Ustav Jadrovych Elektrarni) participation in the NPP V-2 Jaslovske Bohunice Modernization and Safety Improvement Project. A short description of VUJE history, activity, and results is also presented as well as NPPs Jaslovske Bohunice characterization. VUJE was established in 1977 and deals with scientific and research needs of nuclear power plants, such as design, construction, commissioning and operation. The next fields of VUJE activity are, NPP reconstruction, NPP personnel training, radioactive waste management technology, and NPP decommissioning. The nuclear power plant, Jaslovske Bohunice, is situated approximately 15 km from the district town of Trnava in the southwestern region of the Slovak Republic. The construction of the first Czechoslovak NPP A-1 began on this site in 1957 .The construction of the double-unit NPP V-1 with WWER-440 (type V-230) reactor began in 1972. The first unit of NPP V-1 began operation in 1978 and the second in 1980. NPPs construction on the Bohunice site continued with NPP V-2, which has two units with WWER-440 (type V-213) reactors. Unit 1 and Unit 2 of NPP V-2 were commissioned in 1984 and 1985, respectively. Slovak electric utility Slovenske elektrarne (SE) is the owner/commissioner of NPP V-2. This NPP is responsible for more than 20% of the total electrical energy production of SE, making it an essential supporter of the Slovak economy. (authors)

Using the digital reactor control systems at NPP

International Nuclear Information System (INIS)

Schirl, G.; Hertel, J.

2006-01-01

A conception of application of the digital reactor control systems (RCS) at NPP is presented. The digital RCS architecture and safety ensuring are considered. The strategy and algorithm of the operating NPP equipping with the new digital RCS are given too [ru

Radioactive wastes management of NPP

International Nuclear Information System (INIS)

Klyuchnikov, A.A.; Pazukhin, Eh.M.; Shigera, Yu. M.; Shigera, V.Yu.

2005-01-01

Modern knowledge in the field of radiation waste management on example of the most serious man-made accident at Chernobyl NPP are illuminated. This nuclear power plant that after accident in 1986 became in definite aspect an experimental scientific ground, includes all variety of problems which have to be solved by NPP personnel and specialists from scientific organizations. This book is aimed for large sphere of readers. It will be useful for students, engineers, specialists and those working in the field of nuclear power, ionizing source and radiation technology use for acquiring modern experience in nuclear material management

NPP construction cost in Canada

International Nuclear Information System (INIS)

Gorshkov, A.L.

1988-01-01

The structure of capital costs during NPP construction in Canada is considered. Capital costs comprise direct costs (cost of the ground and ground rights, infrastructure, reactor equipment, turbogenerators, electrotechnical equipment, auxiliary equipment), indirect costs (construction equipment and services, engineering works and management services, insurance payments, freight, training, operating expenditures), capital per cents for the period of construction and cost of heavy water storages. It proceeds from the analysis of the construction cost structure for a NPP with the CANDU reactor of unit power of 515, 740 and 880 MW, that direct costs make up on the average 62%

Heat delivery from Bohunice NPP, Slovakia

International Nuclear Information System (INIS)

Paley, I.

1998-01-01

Experience with nuclear district heating in the Slovak Republic is reported. The heating system of the town of Trnava is supplied by the Bohunice NPP and conventional sources. Construction of the hot water heating system from the Bohunice NPP began in 1983. Commercial operation began on 10 December 1987. Heat delivery has gradually increased from 478 TJ in 1988, to 1,104 TJ in 1995. The heat cost is low, resulting in an increasing number of consumers. (author)

Reliability improvement of potential transformer and secondary circuit of 6 kV 1E-class buses in Qinshan nuclear power plant

International Nuclear Information System (INIS)

Qian Houjun

2014-01-01

There are design defects in potential transformer (PT) and secondary circuit of 6 kV 1E-class buses in Qinshan Nuclear Power Plant Nuclear Island. During the operating period, there happened several serious operational events (loss of power) caused by PT resonance. The essay analyses the defects of original design, and put forward corresponding modification measures, which have been carried out by two steps between 2009 and 2010, and after the modification the same problems have not happened again. (author)

Thermal-hydraulic model of the primary coolant circuits for the full-scale training facility with WWER-1000

International Nuclear Information System (INIS)

Kroshilin, A.E.; Zhukavin, A.P.; Pryakhin, V.N.

1992-01-01

The mathematical model realized in the full-scale educational facility for NPP operator training is described. The RETACT computational complex providing real time process simulation for all regimes including the maximum credible accident is used for calculation of thermohydraulic parameters of the primary coolant circuits and steam generator under stationary and transient conditions. The two-velocity two-temperature model of one-dimensional steam-water flow containing uncondensed gases is realized in the program

Experimental lysimetric device NPP A-1

International Nuclear Information System (INIS)

Matusek, I.; Plsko, J.

2002-01-01

In the frame of decommissioning of the NPP A-1 in the locality Jaslovske Bohunice the problem of remedial measures in scope of radioactive contaminated soils is also studied. These soils have originated in the area of the NPP A-1 by different mechanisms as the result of leakages from technology and in the present time they represent the secondary source of contamination of underground waters. Contaminated soils represent the particularity, because we can characterize them as voluminous radioactive contaminated residues with low-level or very low-level activity. EKOSUR Company in the frame of active underground water protection suggested more remedial measures. Two basic tasks are solved in the field of the contaminated soils: rehabilitation of contaminated soils or temporary immobilisation of radionuclides in the contaminated volumes, deposition of rehabilitated soils in the storage of landfill type. In the frame of engineering solution of the landfill storage the question of technology of own deposition of contaminated soils into storage area is important from the safety viewpoint. Therefore the Experimental lysimetric device was built for half-operational test of suggested technologies. This device contains 6 pieces of lysimeters with 6 active volumes of approximately 1 cubic meter. The aim of suggested and in the present time realised experiments is the practical modelling of influence of filtering of waters into storage of contaminated soils in configurational and qualitative different conditions of deposition of soils (for example exploitation of sorption materials). Also the structure of un-rehabilitated soils by the influence of natural downfalls activity is modelled in one lysimeter. In this issue the authors deal with the construction of lysimetric device, proposed experiments as like as gained results of observations. (authors)

Ukrainian Nuclear Society International Conference 'Modernization of the NPP with VVER reactor' (abstracts)

International Nuclear Information System (INIS)

Bar'yakhtar, V.G.

1999-01-01

Abstracts of the papers presented at International conference of the Ukrainian Nuclear Society 'Modernization of the NPP with VVER reactor'. The following problems are considered: improving the NPP's safety and reliability; reactor modernization, the lifetime prolongation; increasing of the reactor operating characteristics; methods of capacity factor increasing: refueling control, maintenance control; technical and economical aspects of NPP modernization; modernization of the automated control system of the fuel process at the NPP's; technical features and methods for the continued radiation and technology control at the NPP's; training, increasing the staff qualification and NPP modernization

IAEA activities on NPP personnel training and qualification

International Nuclear Information System (INIS)

Kossilov, A.

1998-01-01

Activities of IAEA concerning training and qualification of NPP personnel consider the availability of sufficient number of competent personnel which is one of the most critical requirements for safe and reliable NPP operation and maintenance. Competence of personnel is essential for reducing the frequency of events connected to human errors and equipment failures. The IAEA Guidebook on Nuclear Power Plant Personnel Training and its Evaluation incorporates the experience gained worldwide and provides recommendations on the use of SAT being the best practice for attaining and maintaining the qualification and competence of NPP personnel and for quality assurance of training

NPP Krsko on-line low pressure containment tightness monitoring implementation

International Nuclear Information System (INIS)

Dudas, M.; Basic, I.

2004-01-01

Containment Integrated Leak Rate Test (CILRT) 1999 in NPP Krsko was completely performed following regulation of 10CFR50 Appendix J Option A and ANSI/ANS 56.8-1987 at a design pressure (3.15 kp/cm2). In 2001 NPP Krsko proposed to Slovenian Nuclear Safety Administration (SNSA) the Technical Specification (TS) and Updated Safety Analysis Report (USAR) changes that describe implementation of new test intervals for Type A, B and C tests according to 10CFR50, Appendix J, Option B. After the positive final independent review of proposed changes by Authorized Institution, NPP Krsko received the License Amendment requiring from NPP Krsko to define technical solution for surveillance of containment tightness between two 10-years CILRT. This paper intends to discuss proposed methods by NPP Krsko, test equipment, performed measurements in 2004, associated analyses and evaluation.(author)

Integrated NPP life cycle management - Agency's approach

International Nuclear Information System (INIS)

Gueorguiev, B.

2002-01-01

administrative - managerial or/and social - political activities aimed at the achievement of an optimised long term save and reliable operation of the plant including its decommissioning. Optimisation of the plant operational life is the most economical option equivalent to providing additional generating capacity. In its turn optimisation of operational or service life means extension of the operational license to the extent possible having in mind that the plant performance continues to maintain its safety and competitiveness on the market. To meet these requirements the need for an integrated NPP life management approach is becoming more and more evident. The IAEA in response to the needs of the Member states is implementing several programmes including the project on engineering and management practices for optimisation of nuclear power plant service life including decommissioning. The Project scope includes different possible modes of IAEA operations for the purposes of information exchange and technology transfer. It means arrangements for technical, advisory and consultant group meetings, development of databases and guidance documents on proven practices, co-ordinated research projects, technical co-operation projects, expert services, training activities, co-operation with other International organizations and some others. A number of issues are under consideration. They include economic analysis and considerations related to decision on continued operation versus decommissioning, optimisation of operation/maintenance/In-service inspection regimes to facilitate life management programmes, aging management and mitigation measures with regard to control and instrumentation, primary and secondary circuit equipment integrity, assessment of structural materials, creation and development of supporting databases, preservation of knowledge including aspects of training and qualification of NPP personnel, work force aging, pre-shut down and decommissioning activities

Rupture of DN 500 - design basic accident at units 3 and 4 of Kozloduy NPP

International Nuclear Information System (INIS)

Uruchev, V.; Vassilev, P.; Ivanova, A.; Sartmadjiev, A.

2005-01-01

The original design of Kozloduy NPP Units 3 and 4 assumes as Design Basis Accident (DBA) the rupture of DN 32 mm primary pipeline, while an initial event of double-sided guillotine break of primary pipeline with maximal diameter is not considered. In the course of units modernization it have been demonstrated once and again that both the emergency core cooling systems and the localization systems can cope with larger and larger primary circuit leaks. After the installation of a Jet-Vortex Condenser (JVC) at Units 3 and 4 it was substantiated that, the integrity of the hermetic rooms is ensured even in case of double-sided guillotine break of a primary circuit pipeline with maximal diameter (DEGB). The technical justification of the jet-vortex condenser, elaborated by VNIAEC, contains calculations determining both the source term and the doses obtained outside the NPP site after LOCA DN 500. LOCA DN 500 is considered in these analyses as a beyond design basis accident and it is so included in the SAR and approved by the Nuclear Regulatory Agency (NRA). The thermo-hydraulic calculations performed later on show that the emergency core cooling systems can cope with this initial event at conservative assumptions. In order to classify this initiating event as a design basis accident it is necessary to demonstrate that the core cooling criteria are fulfilled and the internal and external doses outside the NPP site are within the permissible limits fixed for design basis accident by the Bulgarian regulatory body (NRA), when using conservative assumptions. For this purpose two consecutive studies were performed - evaluation of the DEGB probability and categorization of the initial event according to the contemporary regulations acting in Republic of Bulgaria. The presented report summarizes the results of the performed conservative analyses of double-sided guillotine break accident of main circulation line taking into account the probability of rupture of large diameter

Spent fuel pool risk analysis for the Dukovany NPP

Energy Technology Data Exchange (ETDEWEB)

Hust' ak, S.; Jaros, M.; Kubicek, J. [UJV Rez, a.s., Husinec-Rez (Czech Republic)

2013-07-01

UJV Rez, a.s. maintains a Living Probabilistic Safety Assessment (Living PSA) program for Dukovany Nuclear Power Plant (NPP) in the Czech Republic. This project has been established as a framework for activities related to risk assessment and to support for risk-informed decision making at this plant. The most extensively used PSA application at Dukovany NPP is risk monitoring of instantaneous (point-in-time) risk during plant operation, especially for the purpose of configuration risk management during plant scheduled outages to avoid risk significant configurations. The scope of PSA for Dukovany NPP includes also determination of a risk contribution from spent fuel pool (SFP) operation to provide recommendations for the prevention and mitigation of SFP accidents and to be applicable for configuration risk management. This paper describes the analysis of internal initiating events (IEs) in PSA for Dukovany NPP, which can contribute to the risk from SFP operation. The analysis of those IEs was done more thoroughly in the PSA for Dukovany NPP in order to be used in instantaneous risk monitoring. (orig.)

Identification of flora and fauna biodiversity at Berau, East Kalimantan in NPP pre site survey

International Nuclear Information System (INIS)

June Mellawati; Fepriadi; Yarianto; Tajudin Laddade

2010-01-01

In pre survey activity of NPP site candidate, environmental aspect is a part of non safety aspect, but the existence as an important area is needed to consider. Pre survey activity of NPP site at Berau East Kalimantan is done for follow up result of agreement of Governor in Kalimantan. Purpose of study is to identify fauna and flora biodiversity in Berau Kalalimantn Timur to complete the data base of environmental aspect at survey activity of NPP site candidate The method used is to conduct an inventory and identification of flora-fauna through secondary data collection, making zoning area based on the type of endangered species, and analyze and evaluate the suitability. The survey location priority the coast area such as Sambaliung District, Derawan, Maratua, Tabalar, Biatan-Lempake, Talisayan, Batu Putih and Biduk-Biduk District, Berau Regency, East Kalimantan Province. Activity is done at June 2008 - June 2009. The results showed that there were various species of flora and fauna that are categorized protected under Law Decree no. 5 of 1990 in the study location. However, some areas such as Tanjung Pandan, Tanjung Bohe northern, southern of Tanjung Ulingan, District Derawan Island, and Batu Putih Talisayan District, and Teluk Sulaiman, Biduk-Biduk District need further study and consideration for zoning interest in nuclear power plants because they meet the existing criteria. (author)

A programming language for composable DNA circuits.

Science.gov (United States)

Phillips, Andrew; Cardelli, Luca

2009-08-06

Recently, a range of information-processing circuits have been implemented in DNA by using strand displacement as their main computational mechanism. Examples include digital logic circuits and catalytic signal amplification circuits that function as efficient molecular detectors. As new paradigms for DNA computation emerge, the development of corresponding languages and tools for these paradigms will help to facilitate the design of DNA circuits and their automatic compilation to nucleotide sequences. We present a programming language for designing and simulating DNA circuits in which strand displacement is the main computational mechanism. The language includes basic elements of sequence domains, toeholds and branch migration, and assumes that strands do not possess any secondary structure. The language is used to model and simulate a variety of circuits, including an entropy-driven catalytic gate, a simple gate motif for synthesizing large-scale circuits and a scheme for implementing an arbitrary system of chemical reactions. The language is a first step towards the design of modelling and simulation tools for DNA strand displacement, which complements the emergence of novel implementation strategies for DNA computing.

Current status of Chernobyl NPP decommissioning

International Nuclear Information System (INIS)

2009-01-01

Strategy of Chernobyl NPP decommissioning with the decommissioning license 2002-2064 is presented. The main activities at the stage of ChNPP units shutdown (2002 - 2012) are: units maintenance in safe state; decommissioning infrastructure construction; unloading of SNF – main activity determining the stage duration; systems and elements final shutdown; decommissioning life-support systems reconstruction; Comprehensive engineering and radiation survey (CERS); dismantling of the reactor facilities external equipment; removal of RAW from units; decommissioning documentation development. The decommissioning activities main results are presented

Meeting up-to-date safety requirements in the Russian NPP projects

International Nuclear Information System (INIS)

Tepkyan, G. O.; Yashkin, A. V.

2014-01-01

Safety features in Russian NPP designs are implemented by the combination of active and passive safety systems • Russian NPP designs are in compliance with up-to-date international and European safety requirements and refer to Generation III+ • Russian state-of-the-art designs have already implemented some design solutions, which take into account “post-Fukushima” requirements. Russian NPP design principles have been approved during the European discussions in spring 2012, including the IAEA extraordinary session addressed to Fukushima NPP accident

Results and development prospects for the Cernavoda NPP

International Nuclear Information System (INIS)

Rotaru, Ioan

2001-01-01

The new competitive market in the power sector offers favorable conditions for continual developing of Nuclear Power in Romania. The principal arguments in this respect are: the CANDU technology is a western technology recognized world wide both for its operation reliability and its economical performances. The results obtained by Cernavoda NPP Unit 1 over a period of four years and a half commercial operation confirms the validity of the CANDU project in Romania in the new conditions of competitive market. Accomplishing the Unit 2 of Cernavoda NPP represents for the time being one of the most cost-effective investment in the Romanian power sector. Also, the participation of the local industry to the project implementation is important as it ensures the initial heavy water and nuclear fuel charging, specific materials and equipment production, design and construction works, etc. Heaving in view all these favorable arguments, the construction of Unit 2 of Cernavoda NPP represents one of the highest priorities of the State Budget of the present administration in year 2001. The Nuclear Power Project in Romania, based on CANDU technology meets national as well as EU regulations concerning nuclear power and as such its development poses no significant problems both in the context of EU extension and in the frame of the developing competitive market in the power sector. For SNN SA the main objectives in view for the next stage are: operating Cernavoda NPP Unit 1 in conditions of highest nuclear safety and economical efficiency; finalizing the Cernavoda NPP Unit 2 and creation of an organisation for operating the two units; promoting of a functional system characteristic to the competitive market economy and open to privatization; creating opportunities for exporting electrical energy. The contribution contains the following sections: 1. General overlook; 2. Performance of the power production in the year 2000; 2.1. Unit 1 of Cernavoda NPP; 2.2. Nuclear Fuel Plant

Quantitative secondary electron detection

Science.gov (United States)

Agrawal, Jyoti; Joy, David C.; Nayak, Subuhadarshi

2018-05-08

Quantitative Secondary Electron Detection (QSED) using the array of solid state devices (SSD) based electron-counters enable critical dimension metrology measurements in materials such as semiconductors, nanomaterials, and biological samples (FIG. 3). Methods and devices effect a quantitative detection of secondary electrons with the array of solid state detectors comprising a number of solid state detectors. An array senses the number of secondary electrons with a plurality of solid state detectors, counting the number of secondary electrons with a time to digital converter circuit in counter mode.

The analysis of financial risk management application for NPP project in Indonesia

International Nuclear Information System (INIS)

Imam Bastori; Moch Djoko Birmano

2012-01-01

NPP Project is one of full dynamic, risky and challenging business. Application of financial risk management t in Nuclear Power Plant (NPP) project becomes one alternative to be considered carefully. This paper explains an analysis to make a decision in the risk management application so that it can be applied in the NPP's construction in Indonesia. As case study, is NPP of conventional PWR type of class 1150 MWe. To calculate the economics and financing of NPP is used Spreadsheet INOVASI, further the decision of financial risk management were analyzed using a Model of Cash Flow Adjustment, which developed by Richard Fairchild. The analysis showed that the Method of Cash Flow Adjustment developed by Richard Fairchild is better than the method of NPV Adjustment on a NPP project, because it have included the aspects of financial risk management. NPP project can only be executed if the NPV 2 0 and decision to execute the financial risk management should be based on NPVrm > NPV. The application of financial risk management in NPP project is not needed if an insurance premium more expensive than all costs of financial distress, unless the insurance company can give discount of at least 20%. (author)

Near Regional and Site Investigations of the Temelin NPP Site

International Nuclear Information System (INIS)

Prachar, Ivan; Vacek, Jiri; Heralecky, Pavel

2011-01-01

The Temelin NPP is worldwide through heated discussion with nuclear energetic opposition. In addition this discussion goes beyond a border of the Czech Republic. On the other side, results of several international supervisions shown that Temelin NPP is fully comparable with the safest nuclear power plants in the world regarding its technical design and safety functions. This presentation deals with the near regional and site investigations of the Temelin NPP Site. It must be noted that although the Temelin site is situated in the area with low seismicity, item of seismicity is a basic argument against Temelin NPP and therefore a detail seismic hazard assessment was performed

Knowledge Management and Organizational Proficiency with NPP

International Nuclear Information System (INIS)

Marler, M.

2016-01-01

Full text: The pace of new NPP construction, startup, and operation is straining the supply of proficient operators, technicians, and engineers. This technical brief explains an approach implemented by a US nuclear utility to capture and transfer knowledge possessed by proficient workers to new workers using the VISION learning content management system. This approach could also be used to accelerate worker proficiency in new NPP organizations. (author

Safeguards at Kozloduy NPP - Experience and expectations

International Nuclear Information System (INIS)

Elenkov, Todor

2001-01-01

Bulgaria is a party of Non Proliferation Treaty since 5 September 1969. The agreement between IAEA and Bulgaria - INFCIRC 178 - has been in force since 29 February 1972. At that time Bulgaria had one research reactor IRT-2000 in Sofia and two power reactors of WWER-440 type under construction. Now at Kozloduy NPP site there are 4 facilities, which consist of 4 WWER-440 and 2 WWER-1000 type power reactors, producing almost 50% of the electricity in Bulgaria and 1 wet away from reactor spent fuel storage. In 1991 under the green movements and social pressure, the research reactor in Sofia was closed and the construction of the second NPP in Belene with 2 WWER-1000 type reactors was halted. After the transfer in 1994 of the fresh fuel from the research reactor to Kozloduy due to security reasons practically NPP Kozloduy remains the only significant (from safeguards point of view) nuclear site in Bulgaria. In 1972 a 'Nuclear Fuel' group was formed at the Physicists Department in NPP Kozloduy with responsibilities to carry out for safeguards records and reports, fresh and spent fuel transport and control. In 1990 this group was transferred to the Safety Section and since 1992 it exists as 'Control and Accounting for of the Nuclear Materials' - a section in the Safety Department. Currently the section serves all four facilities in NPP Kozloduy and has four people: section head, chief inspector and two inspectors. The main activities of the section include: a) Control of the nuclear fuel location as well as meeting the storage and transport conditions regulations; b) Control of the conditions for normal operations of the installed IAEA surveillance systems; c) Preparation of documents for licensing of fresh and spent nuclear fuel transport; d) Preparation of the official information on nuclear materials location and quantity; e) Preparation of accounting records and the reports for IAEA (ICR, PIL, MBR); f) Co-ordination of the IAEA safeguards inspection activities at NPP

Status and objectives of the Bulgarian nuclear energy sector

International Nuclear Information System (INIS)

Kouzmanov, K.

1996-01-01

A brief overview of the current situation and problems to be solved in the Bulgarian nuclear energy is presented. The main task is to increase the availability of the Kozloduy NPP in terms of time and power. The following technical solutions for reconstruction of units 1-4 (WWER-440) are discussed: defence against external events; emergency cooling of the primary and secondary circuits; reliability analysis used in probabilistic safety assessment; management of beyond design basis accident conditions. The necessity of retrofitting of units 5-6 (WWER-1000) and completion of the Belyane NPP project is also stressed

Attitude of the population and students to further construction of NPP

International Nuclear Information System (INIS)

Machacek, Ladislav

1993-01-01

This presentation shows the public opinion poll young people on NPP in the Slovakia i.e. comparative research results on Attitude of the Slovak population (1991 - a sample 1104 respondents, and Slovak students 1992 - a sample 291 respondents) to the nuclear energy and NPP; Source of information about NE and NPP, motivation of apprehensions of young people concerning NE; what meaning for young people have the arguments FOR and AGAINST construction of NPP in Slovakia; whom students from Bratislava believe during discussions about NE

Some problems of NPP construction base improvement

International Nuclear Information System (INIS)

Movchan, S.V.

1984-01-01

NPP construction bases are characterized by high cost of construction and large area. Duration of base construction makes up 3-4 years, labour contents for their erection constitute 600-900 thousand man-days. Delays in organizing functional base services essentially decelerate construction rates of the main NPP buildings. Maximum joining of separate buildings by their functional assignment and structural peculiarities, wide application of container buildings, partial utilization of permanent buildings of production centre for construction needs; transition to new organizational form of construction based on industrial production of buildings; production of volumetric structural-technological cells with mounted equipment manufactured at specialized plants, mounting NPP components with stock produced cells, consideration of the problem of large power centre creation are necessary for reduction of construction centres, area reduction of cost and duration of their construction

Qinshan NPP large break LOCA safety analysis

International Nuclear Information System (INIS)

Shi Guobao; Tang Jiahuan; Zhou Quanfu; Wang Yangding

1997-01-01

Qinshan NPP is the first nuclear power plant in the mainland of China, a 300 MW(e) two-loop PWR. Large break LOCA is the design-basis accident of Qinshan NPP. Based on available computer codes, the own analysis method which complies with Appendix k of 10 CFR 50 has been established. The RELAP4/MOD7 code is employed for the calculations of blowdown, refill and reflood phase of the RCS respectively. The CONTEMPT-LT/028 code is used for the containment pressure and temperature analysis. The temperature transient in the hot rod is calculated using the FRAP-6T code. Conservative initial and functional assumptions were adopted during Qinshan NPP large break LOCA analysis. The results of the analysis show the applicable acceptance criteria for the loss-of-coolant accident are met

Construction of large-thickness sand cushions for NPP foundations

International Nuclear Information System (INIS)

Krantsfel'd, Ya.L.; Losievskaya, I.K.; Kovalenko, R.P.; Mutalipov, A.

1982-01-01

A study is made on some technological peculiarities of preparation of NPP foundations and control methods of foundation density. As an example the experience of cement-sand foundation construction for two 900 MW power-units at the Koeberg South Africa NPP is briefly described. The experience of artificial foundation construction at this NPP indicates both the possibility of obtaining the required quality of cement-sand cushions and commercial construction of large volume of such cushions by acceptable rates and the necessity of unification of work quality characteristics

Irradiation Embrittlement Monitoring Programs of RPV's in the Slovak Republic NPP's

International Nuclear Information System (INIS)

Kupca, Ludovik

2006-01-01

Four types of surveillance programs were (are) realized in Slovak NPP's: 'Standard Surveillance Specimen Program' (SSSP) was finished in Jaslovske Bohunice V-2 Nuclear Power Plant (NPP) Units 3 and 4, 'Extended Surveillance Specimen Program' (ESSP), was prepared for Jaslovske Bohunice NPP V-2 with aim to validate the SSSP results, For the Mochovce NPP Unit 1 and 2 was prepared completely new surveillance program 'Modern Surveillance Specimen Program' (MSSP), based on the philosophy that the results of MSSP must be available during all NPP service life, For the Bohunice V-1 NPP was finished 'New Surveillance Specimen Program' (NSSP) coordinated by IAEA, which gave arguments for prolongation of service life these units for minimum 20 years, New Advanced Surveillance Specimen Program (ASSP) for Bohunice V-2 NPP (units 3 and 4) and Mochovce NPP (units 1, 2) is approved now. ASSP is dealing with the irradiation embrittlement of heat affected zone (HAZ) and RPV's austenitic cladding, which were not evaluated till this time in surveillance programs. SSSP started in 1979 and was finished in 1990. ESSP program started in 1995 and will be finished in 2007, was prepared with aim of: increasing of neutron fluence measurement accuracy, substantial improvement the irradiation temperature measurement, fixed orientation of samples to the centre of the reactor core, minimum differences of neutron dose for all the Charpy-V notch and COD specimens, the dose rate effect evaluation. In the year 1996 was started the new surveillance specimen program for the Mochovce RPV's unit-1 and 2, based on the fundamental postulate - to provide the irradiation embrittlement monitoring till the end of units operation. The 'New Surveillance Specimen Program' (NSSP) prepared in the year 1999 for the Bohunice V-1 NPP was finished in the year 2004. Main goal of this program was to evaluate the weld material properties degradation due to the irradiation and recovery efficiency by annealing too. The

Project No. 7 - Decommissioning unit at Ignalina NPP. (Engineering and project management)

International Nuclear Information System (INIS)

2000-01-01

In order to manage decommissioning process at Ignalina NPP, a new unit should be established in the framework of the Ignalina NPP organizational structure. The on-site Engineering Project Management Unit (PMU) will adopt an integrated approach to project management , engineering design, planning, procurement, safety and licensing activities at Ignalina NPP site. The PMU will assist the Ignalina NPP management in the development of an integrated decommissioning and waste management strategy

Procedure for Application of Software Reliability Growth Models to NPP PSA

International Nuclear Information System (INIS)

Son, Han Seong; Kang, Hyun Gook; Chang, Seung Cheol

2009-01-01

As the use of software increases at nuclear power plants (NPPs), the necessity for including software reliability and/or safety into the NPP Probabilistic Safety Assessment (PSA) rises. This work proposes an application procedure of software reliability growth models (RGMs), which are most widely used to quantify software reliability, to NPP PSA. Through the proposed procedure, it can be determined if a software reliability growth model can be applied to the NPP PSA before its real application. The procedure proposed in this work is expected to be very helpful for incorporating software into NPP PSA

Radionuclide localization at the Chernobyl' NPP territory

International Nuclear Information System (INIS)

Mamaev, L.A.; Galkin, G.A.; Khrabrov, S.L.; Polyakov, A.S.; Mikhejkin, S.V.

1989-01-01

Experience is generalized of using different dust suppression (DS) compounds during Chernobyl' accident consequence elimination. Polymer DS compounds were used at the NPP operating site; the compounds kept dust-like radioactive contaminations during 1-2 months. DS at the country was realized by means of the compound on base of latex. The conclusion is made that the DS measures improved radiation situation in the NPP zone. 7 refs

Preparation of Long Term Operation in Dukovany NPP, Czech Republic

International Nuclear Information System (INIS)

Krivanek, R.; Sabata, M.

2012-01-01

Dukovany NPP in the south-east of the Czech Republic operates four VVER 440/213 type units. The first unit was commissioned in 1985 and the last one in 1987. The operational results of the whole NPP have been excellent and NPP permanently belongs between the first quartile of the best operated NPPs in the world in accordance with WANO factors. Large safety improvement programme have been implemented in last 15 years. The original design lifetime of main components is 30 years which means till 2015 and it is understandable that NPP is preparing for long-term operation (LTO). The paper is describing activities carried out and planned for safe and successful LTO. (author)

Safety analyses of the electrical systems on VVER NPP

International Nuclear Information System (INIS)

Andel, J.

2004-01-01

Energoprojekt Praha has been the main entity responsible for the section on 'Electrical Systems' in the safety reports of the Temelin, Dukovany and Mochovce nuclear power plants. The section comprises 2 main chapters, viz. Offsite Power System (issues of electrical energy production in main generators and the link to the offsite transmission grid) and Onsite Power Systems (AC and DC auxiliary system, both normal and safety related). In the chapter on the off-site system, attention is paid to the analysis of transmission capacity of the 400 kV lines, analysis of transient stability, multiple fault analyses, and probabilistic analyses of the grid and NPP power system reliability. In the chapter on the on-site system, attention is paid to the power balances of the electrical sources and switchboards set for various operational and accident modes, checks of loading and function of service and backup sources, short circuit current calculations, analyses of electrical protections, and analyses of the function and sizing of emergency sources (DG sets and UPS systems). (P.A.)

Low-water considerations for NPP sites

International Nuclear Information System (INIS)

Jensen, J.; Frank, T.; Wahl, T.

2009-01-01

In the frame of reactor safety considerations flood protection and the evaluation of low-water events are safety relevant issues. Therefore low-water statistics were performed for the coastal region Cuxhaven and the Elbe river estuary. The consideration of the longitudinal profile of water levels during low-tide in connection with surface water effects, morphodynamic changes of the river and anthropogenic modifications is of importance for conclusions concerning the NPP sites in some distance of the reference tide gauge. The authors performed a statistical low-tide analysis for the NPP sites Brunsbuettel and Brokdorf.

NPP Krsko natural circulation performance evaluation

International Nuclear Information System (INIS)

Segon, Velimir; Bajs, Tomislav; Frogheri, Monica

1999-01-01

The present document deals with an evaluation of the natural circulation performance of the Krsko nuclear power plant. Two calculation have been performed using the NPP Krsko nodalization (both similar to the LOBI A2-77 natural circulation experiment) - the first with the present steam generators at NPP Krsko (Westinghouse, 18% plugged), the second with the future steam generators (Siemens, 0% plugged). The results were evaluated using the natural circulation flow map derived in /1/, and were compared to evaluate the influence of the new steam generators on the natural circulation performance. (author)

33 CFR 183.435 - Conductors in circuits of 50 volts or more.

Science.gov (United States)

2010-07-01

... HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Electrical Systems Manufacturer... more. (c) This section does not apply to communication systems; electronic navigation equipment; resistance conductors that control circuit amperage; conductors in secondary circuits of ignition systems...

Training human resource for NPP in Vietnam

International Nuclear Information System (INIS)

Nguyen, Trung Tinh; Dam, Xuan Hiep

2008-01-01

Vietnam will establish the first NPP in the near future. With us the first important thing is the human resource, but now there is no university in Vietnam training nuclear engineers. In EPU (Electric Power University), now we are preparing for training nuclear engineers. In this paper, we review the nuclear man power and the way to train the high quality human resource for NPP and for other nuclear application in Vietnam. (author)

Russian normative approach to the question of management of NPP life time

International Nuclear Information System (INIS)

Karpunin, N.I.

2002-01-01

Full text: In Russia, the designated service life of a nuclear power plant (NPP) is 30 years. During the period 2001-2010, 15 Russian NPP units will reach the end of their service life. The 'Basic Provisions of NPP Safety Assurance', OPB-88/97, Item 5.1.14, provide for a possible extension of NPP operation beyond the designated service life. For such an extension, the NPP operating organization must apply for a license renewal to Gosatomnadzor, which needs to specify the relevant requirements. GAN is developing regulatory documents to provide a basis for NPP license renewal/extension of NPP operation, which would benefit from international experience. In accordance with 'The program of Atomic Energy Development in the Russian Federation for 1998-2005 and up to 2010' adopted by Decree No. 815 of the Government of the Russian Federation on 21 July 1998, priority is placed on the preparation of NPPs for extension of service life and on ensuring safety in the extended operating period. The length of the extension beyond the designated service life is to be determined on the basis of a range of technical and economic considerations, including: The ability to ensure and maintain operational safety; Sufficient residual service life of the unit's non-repairable components; The availability of temporary storage facilities for the additional spent nuclear fuel and radioactive waste, or the possibility of its transport off-site; The ability to ensure safe handling of the radioactive waste generated during the extension period; To extend the lifetime of an NPP unit, the plant Operator is required to perform the following tasks: Carry out a comprehensive survey of the NPP unit; Draw up a programme of preparation for lifetime extension; Prepare the NPP unit for operation in the extended period; Carry out the necessary tests. There are also some normative documents, which regulate management of NPP life time. (author)

Observation and modeling of NPP for Pinus elliottii plantation in subtropical China

Institute of Scientific and Technical Information of China (English)

2008-01-01

Based on the stem analysis of 59 individuals of Pinus elliottii in combination with tree biomass models, we calculated annual biomass increment of forest plots at Qianyanzhou Ecological Station, Chinese Academy of Sciences in subtropical China. In addition, canopy layer and community NPP were calcu- lated based on 12 years’ litter fall data. NPP of the 21-year-old forest was estimated by using the BIOME BGC model; and both measured NPP and estimated NPP were compared with flux data. Community biomass was 10574 g·m-2; its distribution patterns in tree layer, shrub layer, herbaceous layer, tree root, herbaceous and shrub roots and fine roots were 7542, 480, 239, 1810, 230, 274 and 239 g·m-2, respectively. From 1999 to 2004, the average annual growth rate and litter fall were 741 g·m-2·a-1 (381.31 gC·m-2·a-1) and 849 g·m?2·a?1 (463 gC·m-2·a-1), respectively. There was a significant corre- lation between annual litter fall and annual biomass increment; and the litter fall was 1.19 times the biomass increment of living trees. From 1985 to 2005, average NPP and GPP values based on BGC modeling were 630.88 (343.31 - 906.42 gC·m-2·a-1) and 1 800 gC·m-2·a-1 (1351.62 - 2318.26 gC·m-2·a-1). Regression analysis showed a linear relationship (R2=0.48) between the measured and simulated tree layer NPP values. NPP accounted for 30.2% (25.6%-32.9%) of GPP, while NEP ac- counted for 57.5% (48.1%-66.5%) of tree-layer NPP and 41.74% (37%-52%) of stand NPP. Soil respi- ration accounted for 77.0% of measured tree NPP and 55.9% of the measured stand NPP. NEE based on eddy covariance method was 12.97% higher than the observed NEP.

Actual status of project Mochovce NPP units 3 and 4 completion

International Nuclear Information System (INIS)

Niznan, S.

2005-01-01

In this presentation author deals with actual status of project Mochovce NPP units 3 and 4 completion. Present state of Mochovce NPP, Units 3 and 4 enables real assumption to completion. It is expected that such supplier companies can be used which are experienced in field of nuclear projects. Based on budget of 2002, it seems that completion costs of 45 billions SKK are real. These figures were confirmed by study performed by TRACTEBEL in 2004. Based on experience from Bohunice NPP completion as well as from Mochovce NPP, Units 1 and 2 completion and if decision milestone and project start up deadlines will be observed according to modified preliminary schedule of Mochovce NPP Units 3 and 4 completion, it seems as real that Unit 3 will be completed till 06/2011 and Unit 4 - till 12/2011.

High-Voltage MOSFET Switching Circuit

Science.gov (United States)

Jensen, Kenneth A.

1995-01-01

Circuit reliably switches power at supply potential of minus 1,500 V, with controlled frequency and duty cycle. Used in argon-plasma ion-bombardment equipment for texturing copper electrodes, as described in "Texturing Copper To Reduce Secondary Emission of Electrons" (LEW-15898), also adapted to use in powering gaseous flash lamps and stroboscopes.

Review of accident analyses performed at Mochovce NPP

International Nuclear Information System (INIS)

Siko, D.

2000-01-01

In this paper the review of accident analysis performed in NPP Mochovce V-1 is presented. The scope of these safety measures was defined and development in the T SSM for NPP Mochovce Nuclear Safety Improvements Report' issued in July 1995. The main objectives of these safety measures were the followings: (a) to establish the criteria for selection and classification of accidental events, as well as defining the list of initiating events to be analysed. Accident classification to the individual groups must be performed in accordance with RG 1.70 and IAEA recommendations 'Guidelines for Accidental Analysis of WWER NPP' (IAEA-EBR-WWER-01) to select boundary cases to be calculated from the scope of initiating events; (b ) to elaborate the accident analysis methodology that also includes acceptance criteria for their result evaluation, initial and boundary conditions, assumption related with the application of the single failure criteria, requirements on the analysis quality, used computer codes, as well as NPP models and input data for the accident analysis; (c) to perform the accident analysis for the Pre-operational Safety Report (POSAR); (d) to provide a synthetic report addressing the validity range of codes models and correlations, the assessment against relevant tests results, the evidence of the user qualification, the modernisation and nodding scheme for the plant and the justification of used computer codes. Analyses results showed that all acceptance criteria were met with satisfactory margin and design of the NPP Mochovce is accurate. (author)

The Bohunice NPP V-1 units nuclear safety upgrading

International Nuclear Information System (INIS)

Mlcuch, M.

2000-01-01

Safety upgrading and operational reliability improvement was carried out by the Bohunice NPP V-1 staff continuously since the plant commissioning. By now, more than 1200 minor or major modifications have been implemented, either by the NPP maintenance staff or by the contractors. Based on findings of safety assessment missions invited by Bohunice NPP in 1990 - 1991, the Czecho-slovak Nuclear Regulatory Authority (CSKAE) issued the decision No. 5/91 of 81 safety upgrading measures to be taken in different areas. These improvements are referred to as the 'Small Reconstruction of the Bohunice V-1 NPP'. Realization of measures during Small reconstruction of the Bohunice NPP V-1 became a power plant, which further operation is acceptable from safety point of view, but it is also necessary further safety improvement. During the period of the Small Reconstruction the development of a Safety Report for the Gradual reconstruction has been completed. Based on this report the SR Nuclear Regulatory Authority issued the Decision No. 1/94, in which requires 59 upgrading measures in different areas to be addressed. The development of Basic Engineering of the Gradual Reconstruction has been contracted to the Siemens AG. Implementation of safety measures are provided through contract with the consortium REKON (which consists of Siemens AG company and Nuclear Power Plants Research Institute Trnava) and other Czech, Russian and Slovak companies. The Gradual Reconstruction of Bohunice NPP V-1 will be finished in 2000. By implementation of the measures carried out during Gradual Reconstruction achievement of an internationally acceptable nuclear safety level will be reached. (author)

To the problem of reliability standardization in computer-aided manufacturing at NPP units

International Nuclear Information System (INIS)

Yastrebenetskij, M.A.; Shvyryaev, Yu.V.; Spektor, L.I.; Nikonenko, I.V.

1989-01-01

The problems of reliability standardization in computer-aided manufacturing of NPP units considering the following approaches: computer-aided manufacturing of NPP units as a part of automated technological complex; computer-aided manufacturing of NPP units as multi-functional system, are analyzed. Selection of the composition of reliability indeces for computer-aided manufacturing of NPP units for each of the approaches considered is substantiated

Revision of Krsko NPP Quality Assurance Plan

International Nuclear Information System (INIS)

Biscan, R.; Fifnja, I.; Kavsek, D.

2012-01-01

International standards from nuclear power plant operation area are being frequently upgraded and revised in accordance with the continuous improvement philosophy. This philosophy applies also to the area of Quality Assurance, which has also undergone significant improvement since the early 1950s. Besides just nuclear industry, there are also other international quality standards that are being continuously developed and revised, bringing needs for upgrades also in the nuclear application. Since the beginning of Krsko NPP construction, the overall Quality Assurance program and its applicable procedures were in place to assure that all planned and systematic actions necessary to provide adequate confidence that an item or service will satisfy given requirements to quality, are in place. The overall requirements for quality as one of the major objectives for Krsko NPP operation are also set forth in the Updated Safety Analyses Report, the document that serves as a base for operating license. During more than 30 years of Krsko NPP operation, the quality requirements and related documents were revised and upgraded in several attempts. The latest revision 6 of QD-1, Quality Assurance Plan was issued during the year 2011. The bases for the revision were: Changes of the Slovenian regulatory requirements (ZVISJV, JV5, JV9?), Changes of Krsko NPP licensing documents (USAR section 13?), SNSA inspection requirements, Changes of international standards (IAEA, ISO?), Conclusions of first PSR, Implementation of ISO standards in Krsko NPP (ISO14001, ISO17025), Changes of plant procedures, etc. One of the most obvious changes was the enlargement of the QA Plan scope to cover interdisciplinary areas defined in the plant management program MD-1, such as Safety culture, Self-assessment, Human performance, Industrial Safety etc. The attachment of the QA Plan defining relationships between certain standards was also updated to provide matrix for better correlation of requirements of

The final report of the state scientific programme 'Ignalina NPP and the Environment'

International Nuclear Information System (INIS)

1998-03-01

The final report of the State Scientific Programme 'Ignalina NPP and the Environment' includes the generalised research material on the after effects of Ignalina NPP operation upon natural environment and social processes. The data on changes of thermal state and water balance of lake Drukshiai; the effect of permanent thermal and chemical pollution on the water chemical composition and hydrochemical regime; the geochemical - contaminated state; the condition, dynamics and changes of hydrobiont communities in lake Drukshiai; the bio indication of ecological effects; the toxic and genotoxic influence of Ignalina NPP waste waters and lake Drukshiai water as well as bottom sediments; the state and dynamic of landscape ecosystem components of Ignalina NPP region; the radionuclides in Ignalina NPP area, the medical and biological studies in the Ignalina NPP influence population zone; the impact of Ignalina NPP on social territorial processes in the region are presented. Radioecological and ecotoxilogical state of Ignalina NPP region and lake Drukshiai is estimated as well as changes in lake Drukshiai and Ignalina NPP surrounding area ecosystems under the combine anthropogenic of the plant influence are elucidated. The final report contains the results of final report by the executors of the tasks and themes of the Programme which have been obtained since the beginning of the implementation of the Programme as well as generalising conclusions and recommendations. (author)

Fire hazard analysis at the first unit of the Ignalina nuclear power plant: 1. Analysis of fire prevention and ventilation systems and secondary effects

International Nuclear Information System (INIS)

Poskas, P.; Simonis, V.; Zujus, R. and others

2004-01-01

Evaluation of the fire prevention and ventilation systems and the secondary effects on safety at the Ignalina NPP from the point of view of fire hazard using computerized system is presented. Simplified screening algorithms for fire prevention, ventilation and the evaluation of secondary effects are developed, which allow accelerating fire hazard analysis at the Ignalina NPP. The analysis indicated that the fire prevention systems practically meet the national requirements and international recommendations for fire prevention. But it is necessary to introduce in separate rooms the measures improving fire prevention to guarantee the effective functioning of the ventilation systems and the reduction of the influence of secondary effects on safety. Computerized system of fire prevention and ventilation systems and evaluation of secondary effects on safety can be easily applied for fire hazard analysis at different big plants. (author)

Nuclear fuel operation at Balakovo NPP

International Nuclear Information System (INIS)

Morozov, A.

2015-01-01

The presentation addressed the positive experience of the TVS-2M assemblies implementation at Balakovo NPP in 18 month fuel cycles, at uprated power (104%) and the usage of the axial profiled Gd-rods in order to minimize the power peaking factors and linear heat rate in the upper part in some of the fuel rods. The results of the test operation of fuel rods with different claddings, made by E110M, E125 and E635M alloys at Balakovo NPP were also provided. The recently observed problem with the “white crust” on the cladding surfaces was also discussed

Lifetime evaluation of Bohunice NPP components

International Nuclear Information System (INIS)

Kupca, L.

2001-01-01

The paper discuss some aspects of the main primary components lifetime evaluation program in Bohunice NPP which is performed by Nuclear Power Plant Research Institute (NPPRI) Trnava in cooperation with Bohunice and other organizations involved. Facts presented here are based on the NPPRI research report which is regularly issued after each reactor fuel campaign under conditions of project resulted from the contract between NPPRI and Bohunice NPP. For the calculations, there has been used some computer codes adapted (or made) by NPPRI and the results are just the conclusive and very brief, presented here in Tables (Figures). (authors)

Safety upgrading program in NPP Mochovce

International Nuclear Information System (INIS)

Baumeister, P.

1999-01-01

EMO interest is to operate only nuclear power plants with high standards of nuclear safety. This aim EMO declare on preparation completion and commissioning of Mochovce Nuclear Power Plant. Wide co-operation of our company with International Atomic Energy Agency and west European Inst.ions and companies has been started with aim to fulfil the nuclear safety requirements for Mochovce NPP. Set of 87 safety measures was implemented at Mochovce Unit 1 and is under construction at Unit 2. Mochovce NPP approach to safety upgrading implementation is showed on chosen measures. This presentation is focused on the issues category III.(author)

Experience on implementing risk-oriented in-service inspection at NPP in USA

International Nuclear Information System (INIS)

Grebenyuk, Yu.P.; Zaritskij, N.S.; Kovyrshin, V.G.; Kostenko, S.P.

2001-01-01

Experience of implementing risk-oriented in-service inspection (RIISI) of pipelines at the US NPP analyzed. RIISI processes according to the methodologies developed by Westinghouse and EPRI are described and compared. The information is addressed concerning practical matters of RIISI implementing at NPP Beaver Valley and Arkansas Nuclear One. Regulatory activity of the US NRC while implementing NRC at the US NPP. It is shown that using RIISI at NPP is aimed at improvement of examination efficiency, decreasing costs and occupational dose loads while inspecting pipelines

Assistance in chemistry and chemical processes related to primary, secondary and ancillary systems of nuclear power plants

International Nuclear Information System (INIS)

Chocron, Mauricio A.; Becquart, Elena T.; Iglesias, Alberto M.; La Gamma, Ana M.; Villegas, Marina

2003-01-01

Argentina is currently running two nuclear power plants: Atucha I (CNA I) and Embalse (CNE) operated by Nucleoelectrica Argentina (NASA) whereas the National Atomic Energy Commission (CNEA), among other activities, is responsible for research and development in the nuclear field, operates research reactors and carries out projects related to them. In particular, the Reactor Chemistry Section personnel (currently part of the Chemistry Dept.) has been working on the field of reactor water chemistry for more than 25 years, on research and support to the NPPs chemistry department. Though the most relevant tasks have been connected to primary and secondary circuits chemistry, ancillary systems show along the time unexpected problems or feasible improvements originated in the undergoing operating time as well as in phenomena not foreseen by the constructors. In the present paper are presented the tasks performed in relation to the following systems of Embalse NPP: 1) Heavy water upgrade column preliminary water treatment; 2) Liquid waste system preliminary water treatment; and 3) Primary heat transport system coolant crud composition. (author)

Perspectives for utilization of the experience from the electrical equipment modernization of Kozloduy NPP units 5 and 6 in case of construction of new NPP

International Nuclear Information System (INIS)

Bogdanov, D.

2005-01-01

In 2005 a governmental decision for continue the project for construction of Belene NPP was adopted. In case of start of this significant project in short terms, a good option will be to utilize the already achieved experience by the modernization program of units 5 and 6 of Kozloduy NPP. The process of construction of new NPP is associated with significant amount of engineering, civil construction works, equipment order and delivery, installation works, testing and commissioning activities. It is vital necessity to have optimal technology, strict organization for project implementation and excellent documentation. From technical point of view the experience from the modernization of units 5 and 6 of Kozloduy NPP will be very important in case of utilization of similar types of WWER 1000 units. According to the 'Feasibility study for construction of Belene NPP', the most favorable option is to accomplish the already partially constructed Unit 1 on the basis of upgraded WWER B-320 design - WWER 1000 B-392, in order to fulfill IEC 331-3A, IEC 332-3A, and of US NRC Regulatory Guide 1.70 and to construct the second unit on the basis of ASE WWER/1000 B-466. However, for any type of unit selected, the achieved experience will be an important basis. This article is focused mostly on the modernization aspects of some electrical systems of Kozloduy NPP

Development of the automatic test pattern generation for NPP digital electronic circuits using the degree of freedom concept

International Nuclear Information System (INIS)

Kim, D.S.; Seong, P.H.

1995-01-01

In this paper, an improved algorithm for automatic test pattern generation (ATG) for nuclear power plant digital electronic circuits--the combinational type of logic circuits is presented. For accelerating and improving the ATG process for combinational circuits the presented ATG algorithm has the new concept--the degree of freedom (DF). The DF, directly computed from the system descriptions such as types of gates and their interconnections, is the criterion to decide which among several alternate lines' logic values required along each path promises to be the most effective in order to accelerate and improve the ATG process. Based on the DF the proposed ATG algorithm is implemented in the automatic fault diagnosis system (AFDS) which incorporates the advanced fault diagnosis method of artificial intelligence technique, it is shown that the AFDS using the ATG algorithm makes Universal Card (UV Card) testing much faster than the present testing practice or by using exhaustive testing sets

Evaluation of the atmospheric transport modeling tools used at the Ignalina NPP

International Nuclear Information System (INIS)

Jasiulionis, R.

2004-01-01

The atmospheric transport modeling system at the Ignalina NPP is part of the radionuclide monitoring system and is designed to help associate radionuclide network signals with possible source regions. The evaluation of the Atmospheric Transport Modeling Tools Used at the Ignalina NPP was based on results published in last years. The model based on semi-empirical formulae of turbulent diffusion in the air and local meteorological data were used for calculation of concentration of radionuclides emitted through the Ignalina NPP stack. Meteorological data (wind velocity and direction as well as temperature at a height of 2 and 30 meters) were obtained from the meteorological station of the Ignalina NPP at Visaginas. Using the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model, trajectories of air masses transport to the Ignalina NPP region (56.55 N, 26.57 E) during 95 hours at heights of 100, 500 and 1000 m were calculated. The dispersion in the ground-level air of emissions through the Ignalina NPP stack can also be calculated using the HYSPLIT model. The data on the radionuclide activity concentrations in the air at the measurements site and results of calculation can used for the establishment of their field in the Ignalina NPP region. (author)

The primary circuit materials properties results analysis performed on archive material used in NPP V-1 and Kola NPP Units 1 and 2

Energy Technology Data Exchange (ETDEWEB)

Kupca, L.; Beno, P. [Nuclear Power Plants Research Institute Inc., Trnava (Slovakia)

1997-04-01

A very brief summary is provided of a primary circuit piping material properties analysis. The analysis was performed for the Bohunice V-1 reactor and the Kola-1 and -2 reactors. Assessment was performed on Bohunice V-1 archive materials and primary piping material cut from the Kola units after 100,000 hours of operation. Main research program tasks included analysis of mechanical properties, corrosion stability, and microstructural properties. Analysis results are not provided.

NPP Krsko Containment Response Following Main Steam Line Break

International Nuclear Information System (INIS)

Spalj, S.; Grgic, D.; Cavlina, N.

2000-01-01

This paper presents the calculation of thermohydraulic environmental parameters (pressure and temperature) inside containment of Krsko NPP after postulated Main Steam Line Break (MSLB) accident. This analysis was done as a part of the ambient parameters specification in the frame of the NPP Krsko Equipment Qualification (EQ) project. The RELAP5/mod2 computer code was used for the determination of MSLB mass and energy release and computer code GOTHIC was used to calculate pressure and temperature profiles inside NPP Krsko containment. The analysis was performed for spectrum of break sizes to account for possible steam superheating during accidents with smaller break sizes. (author)

Prospects for the NPP Krsko Radioactive Waste Management

International Nuclear Information System (INIS)

Knapp, A.; Levanat, I.; Saponja-Milutinovic, D.

2016-01-01

Croatia adopted Strategy of radioactive waste, used sources and spent fuel management in 2014, and its Law on radiological and nuclear safety was accordingly modified in 2015. The Strategy foresees (though with some flexibility) and the Law declares decidedly that Croatia will establish a Center for radioactive waste management, in which all necessary facilities for storage and subsequent disposal of the Croatian share of the NPP Krsko radioactive waste and spent fuel will be developed. However, Slovenia and Croatia have recently agreed that a long-term dry storage for spent fuel will be established on the NPP premises by the year 2019. Therefore, only the issues of low and intermediate level waste (LILW) are addressed here. In Slovenia, the LILW repository site Vrbina in Krsko municipality was officially confirmed in 2009. Based on the 2013 investment program for a silo-type disposal facility, preparation of the repository project documentation was contracted with a national engineering company in 2014. Slovenian repository concept has been developed in two variants: one for the Slovenian LILW only, and the other intended to accept the Croatian share of LILW from the NPP as well. In the summer of 2015 Slovenia for the first time made an official offer to Croatia to use Vrbina repository for that purpose. However, the Croatian Strategy also does not preclude the option of management of all LILW from the NPP in Croatia. Therefore, present plan of activities for the third revision of the NPP radioactive waste and spent fuel management program outlines hypothetically symmetrical LILW management options: all in Slovenia, or all in Croatia, or one half in each country. So, what shall it be? This paper discusses the prospects for each of the three above mentioned options. The major problem of the Slovenian disposal plan is its high cost, mostly due to high compensations to the local community, which will be hard to finance without Croatian participation. The simplest

Assessment of NPP VIIRS Ocean Color Data Products: Hope and Risk

Science.gov (United States)

Turpie, Kevin R.; Meister, Gerhard; Eplee, Gene; Barnes, Robert A.; Franz, Bryan; Patt, Frederick S.; Robinson, Wayne d.; McClain, Charles R.

2010-01-01

For several years, the NASA/Goddard Space Flight Center (GSFC) NPP VIIRS Ocean Science Team (VOST) provided substantial scientific input to the NPP project regarding the use of Visible Infrared Imaging Radiometer Suite (VIIRS) to create science quality ocean color data products. This work has culminated into an assessment of the NPP project and the VIIRS instrument's capability to produce science quality Ocean Color data products. The VOST concluded that many characteristics were similar to earlier instruments, including SeaWiFS or MODIS Aqua. Though instrument performance and calibration risks do exist, it was concluded that programmatic and algorithm issues dominate concerns. Keywords: NPP, VIIRS, Ocean Color, satellite remote sensing, climate data record.

The Ignalina NPP and Y2K Problem

International Nuclear Information System (INIS)

Medeliene, D.

2000-01-01

Work on preparing the hardware and software of the Ignalina NPP for the year 2000 was started in December 1998. First of all, a Y2K project team was formed comprising 29 specialists. Some of these are the most experienced computer specialist, others co-ordinate work on the Y2K problem at the divisions of the NPP using computers or microprocessors. The project head was appointed and the schedule of work confirmed. In accordance with the schedule, the work was divided into twelve stages. The results showed that the preparations were adequate. On the New Year night the specialists of the Ignalina NPP Emergency Operation Centre worked together with the managers of the plant. Relation with other Lithuanian and international organisations was established. No any Y2K related event happened

The local impacts of Borssele NPP closing down

International Nuclear Information System (INIS)

Mandos, J.L.

2000-01-01

The municipal council of Borsele considers that the use of nuclear energy is a question of national policy, but considers itself responsible for town and country planning, safety and employment. The two latter aspects are especially significant if plans for shutdown are concerned. Confidence in safety of the NPP in Borsele has increased in recent years due to transparent information policy of the power plant itself as well as the local government and most of the employees living in the area. If considering the circumstances under which the decision about the closure of NPP one could sees this is a purely political decision. The local government will continue the close cooperation with the National government and the Parliament in solving the problem of employment and social impact of NPP shutdown

Technical innovations at NPP Dukovany - for safe and efficient operation

International Nuclear Information System (INIS)

Sabata, M.; Vasa, I.

2000-01-01

Inherent features of the NPP Dukovany design provide a significant confidence in its nuclear safety assurance; among these features should be emphasised the reactor core stability and its control and protection system capability to hold the reactor in safe state following scram or accident conditions. Nevertheless, NPP Dukovany was designed in the early seventies, and current requirements for nuclear safety assurance are more strict and/or specific as a result of the technical development and lessons learned from nuclear accidents. The paper compares the safety design base established at the time of NPP Dukovany project implementation and the current reference design base. The paper also presents procedures applied to implement technical and operational measures which are introduced to fulfil the current basic safety criteria. The scope of such measures applied at NPP Dukovany is compared with that of EU countries introduced for the same reason - to meet the updated safety related requirements. Examples of some innovations already implemented or under implementation give an idea how NPP Dukovany proceeds in reaching the goal of harmonising its safety with the requirements to be met before the Czech Republic becomes a member country of the European Union. (author)

Radiological impact on the surrounding area of Cernavoda NPP operation

International Nuclear Information System (INIS)

Busnita, M.; Penescu, M.; Neacsu, L.; Ion, M.; Moldoveanu, E.

1996-01-01

The objective of this paper is to present the protective measures provided to Cernavoda NPP for population and environment in case of normal operation and accidental situations. The paper describes the nuclear safety concept with the two aspects, the technical safety and the radiation protection, respectively, which represent the theoretical basis of the NPP design, construction and operation. The assessment of the potential radiological effects of Cernavoda NPP operation on the population and other environmental factors have been done by using the following input data: the natural and social characteristics of the site and the technical characteristics of the plant. The effects of Cernavoda NPP operation are also exposed in health risks which are compared with the daily risks of the population exposed of the natural phenomena or to the activities like transportation, domestics or industrial. (author). 1 tab., 6 refs

Current status of NPP generation IV

International Nuclear Information System (INIS)

Yohanes Dwi Anggoro; Dharu Dewi; Nurlaila; Arief Tris Yuliyanto

2013-01-01

Today development of nuclear technology has reached the stage of research and development of Generation IV nuclear power plants (advanced reactor systems) which is an innovative development from the previous generation of nuclear power plants. There are six types of power generation IV reactors, namely: Very High Temperature Reactor (VHTR), Sodium-cooled Fast Reactor (SFR), Gas-cooled Fast Reactor (GFR), Lead-cooled Fast Reactor (LFR), Molten Salt Reactor (MSR), and Super Critical Water-cooled Reactor (SCWR). The purpose of this study is to know the development of Generation IV nuclear power plants that have been done by the thirteen countries that are members of the Gen IV International Forum (GIF). The method used is review study and refers to various studies related to the current status of research and development of generation IV nuclear power. The result of this study showed that the systems and technology on Generation IV nuclear power plants offer significant advances in sustainability, safety and reliability, economics, and proliferation resistance and physical protection. In addition, based on the research and development experience is estimated that: SFR can be used optimally in 2015, VHTR in 2020, while NPP types GFR, LFR, MSR, and SCWR in 2025. Utilization of NPP generation IV said to be optimal if fulfill the goal of NPP generation IV, such as: capable to generate energy sustainability and promote long-term availability of nuclear fuel, minimize nuclear waste and reduce the long term stewardship burden, has an advantage in the field of safety and reliability compared to the previous generation of NPP and VHTR technology have a good prospects in Indonesia. (author)

A reliability evaluation method for NPP safety DCS application software

International Nuclear Information System (INIS)

Li Yunjian; Zhang Lei; Liu Yuan

2014-01-01

In the field of nuclear power plant (NPP) digital i and c application, reliability evaluation for safety DCS application software is a key obstacle to be removed. In order to quantitatively evaluate reliability of NPP safety DCS application software, this paper propose a reliability evaluating method based on software development life cycle every stage's v and v defects density characteristics, by which the operating reliability level of the software can be predicted before its delivery, and helps to improve the reliability of NPP safety important software. (authors)

Knowledge management in the NPP domain

International Nuclear Information System (INIS)

Nilsen, Svein; Bisio, Rossella; Ludvigsen, Jan Tore

2004-03-01

This report gives an outlook on Knowledge Management (KM) activities within NPP related establishments as of today. There may be less activity in the NPP world as compared to many other industrial sectors. Still there is an awakening within the NPP industry demanding that KM should be attended to at a larger scale. The most notable reason for this is maybe an imminent increase in the number of people going into retirement. The types of establishments involved cover the major kinds such as utilities, research institutes and worldwide nuclear organizations. The report sums up a few of those efforts that are presently being implemented. Moreover the report looks at general advancements within the field of knowledge management. Simply stated the endeavours belong to either one of two classes. The first class emphasize the use of technology to solve knowledge management problems. The second class regard knowledge management as a problem pertaining to human factors and organizational issues. This report maintain that knowledge management initiatives should make due considerations to both perspectives. This report also sums up the Halden Reactor Project short term KM initiative. (Author)

Medical consequences of NPP and TPP operation

International Nuclear Information System (INIS)

Bliznakov, V.

1996-01-01

Results from a comparative analysis of health conditions of the staff in the Kozloduy NPP and the Maritsa Iztok TPP are reported. It is found that the general disease incidence with temporary incapacity for work of Kozloduy workers is lower than those data for the workers at thermal power stations. The incidence of some social diseases like neoplasms, TBC, hypertension, ischemia etc. is also lower for the staff of NPP. No cases of radiation injuries have been registered for a period of 21 years

NPP Krsko analysis of the loss of the RHR system during mid-loop operation

International Nuclear Information System (INIS)

Bencik, V.; Feretic, D.; Debrecin, N.

2002-01-01

In the paper the results of the NPP Krsko analysis of the loss of the Residual Heat Removal (RHR) system at mid-loop conditions using RELAP5/MOD 3.2.2 Gamma and RELAP5/MOD 3.3 Beta code are presented. Both pressurizer and Steam Generator (SG) 1 manway were open. The facility was open to the containment atmosphere and filled with air above liquid level. Loss of the RHR system when Reactor Coolant System (RCS) is open causes quick boiling in the core and loss of the inventory available for the cooling of the core through the openings. Aims of the analysis were threefold. First, the consequences of the transient for NPP Krsko, i.e., the time to core uncovery was determined. Secondly, the influence of the applied RELAP5 code version (MOD 3.2.2 Gamma and MOD 3.3 Beta) in the analysis of that particular transient with noncondensable gases was assessed. Third, the analysis with SG secondary sides under wet lay-up conditions was performed in order to assess the influence of condensation in the SG U tubes on liquid inventory in the system and core cooling capability.(author)

International Conference of Ukrainian Nuclear Society ''NPP's safety and protection''(annotations)

International Nuclear Information System (INIS)

Barbashev, S.V.

1997-01-01

The abstracts of reports submitted to the Conference include: - New developments of the safe nuclear installations; - NPP ecological safety; - Methods of personnel and population protection; - Waste management safety (at transportation, processing and storage); - Spent nuclear fuel management; - NPP life extension and decommissioning; - Public opinion as an element of NPP safety; - Training of personnel, scientific support and safety culture; - Forecasting of nuclear power and industry safe development; - Development of international cooperation in nuclear power

NPP Krsko Living PSA Concept

International Nuclear Information System (INIS)

Vrbanic, I.; Spiler, J.

2000-01-01

NPP Krsko developed PSA model of internal and external initiators within the frame of the Individual Plant Examination (IPE) project. Within this project PSA model was used to examine the existing plant design features. In order to continue with use of this PSA model upon the completion of IPE in various risk-informed applications in support of plant operation and evaluations of design changes, an appropriate living PSA concept needed to be defined. The Living PSA concept is in NPP Krsko considered as being a set of activities pursued in order to update existing PSA model in a manner that it appropriately represents the plant design, operation practice and history. Only a PSA model which is being updated in this manner can serve as a platform for plant-specific risk informed applications. The NPP Krsko living PSA concept is based on the following major ponts. First, the baseline PSA model is defined, which is to be maintained and updated and which is to be reference point for any risk-informed application. Second, issues having a potential for impact on baseline PSA model are identified and procedure and responsibilities for their permanent monitoring and evaluation are established. Third, manner is defined in which consequential changes to baseline PSA model are implemented and controlled, together with associated responsibilities. Finally, the process is defined by which the existing version of baseline PSA model is superseded by a new one. Each time a new version of baseline PSA model is released, it would be re-quantified and the results evaluated and interpreted. By documenting these re-quantifications and evaluations of results in a sequence, the track is being kept of changes in long-term averaged risk perspective, represented by long-term averaged frequencies of core damage and pre-defined release categories. These major topics of NPP Krsko living PSA concept are presented and discussed in the paper. (author)

NPP Krsko small break LOCA analysis

International Nuclear Information System (INIS)

Mavko, B.; Petelin, S.; Peterlin, G.

1987-01-01

Parametric analysis of small break loss of coolant accident for the Krsko NPP was calculated by using RELAP5/MOD1 computer code. The model that was used in our calculations has been improved over several years and was previously tested in simulation (s) of start-up tests and known NPP Krsko transients. In our calculations we modelled automatic actions initiated by control, safety and protection systems. We also modelled the required operator actions as specified in emergency operating instructions. In small-break LOCA calculations, we varied break sizes in the cold leg. The influence of steam generator tube plugging on small break LOCA accidents was also analysed. (author)

Quantitative analysis of psychological personality for NPP operators

International Nuclear Information System (INIS)

Gao Jia; Huang Xiangrui

1998-01-01

The author introduces the relevant personality quantitative psychological research work carried out by 'Prognoz' Laboratory and Taiwan, and presents the primary results of the research for Chinese Nuclear Power Plant (NPP) operator's psychological personality assessment, which based on the survey of MMPI, and presents the main contents for the personality quantitative psychological research in NPP of China. And emphasizes the need to carry out psychological selection and training in nuclear industry

Grassland Npp Monitoring Based on Multi-Source Remote Sensing Data Fusion

Science.gov (United States)

Cai, Y. R.; Zheng, J. H.; Du, M. J.; Mu, C.; Peng, J.

2018-04-01

Vegetation is an important part of the terrestrial ecosystem. It plays an important role in the energy and material exchange of the ground-atmosphere system and is a key part of the global carbon cycle process.Climate change has an important influence on the carbon cycle of terrestrial ecosystems. Net Primary Productivity (Net Primary Productivity)is an important parameter for evaluating global terrestrial ecosystems. For the Xinjiang region, the study of grassland NPP has gradually become a hot issue in the ecological environment.Increasing the estimation accuracy of NPP is of great significance to the development of the ecosystem in Xinjiang. Based on the third-generation GIMMS AVHRR NDVI global vegetation dataset and the MODIS NDVI (MOD13A3) collected each month by the United States Atmospheric and Oceanic Administration (NOAA),combining the advantages of different remotely sensed datasets, this paper obtained the maximum synthesis fusion for New normalized vegetation index (NDVI) time series in 2006-2015.Analysis of Net Primary Productivity of Grassland Vegetation in Xinjiang Using Improved CASA Model The method described in this article proves the feasibility of applying data processing, and the accuracy of the NPP calculation using the fusion processed NDVI has been greatly improved. The results show that: (1) The NPP calculated from the new normalized vegetation index (NDVI) obtained from the fusion of GIMMS AVHRR NDVI and MODIS NDVI is significantly higher than the NPP calculated from these two raw data; (2) The grassland NPP in Xinjiang Interannual changes show an overall increase trend; interannual changes in NPP have a certain relationship with precipitation.

Dukovany NPP - Safely 16 TERA

International Nuclear Information System (INIS)

Vlcek, J.

2008-01-01

In this presentation increasing of power output of the Dukovany NPP is reviewed. To operate all Dukovany Units safely with the perspective of long-term operation (LTO) of 50 - 60 years it is proposed.

Software for the diagnostic system of the secondary circuit of the Temelin nuclear power plant

International Nuclear Information System (INIS)

Drab, J.

1990-01-01

The secondary circuit of unit 1 of the Temelin nuclear power plant will be fitted with an automated diagnostic system, whose objects include the turbine and generator; feedwater pumps and their turbines; separator-reheater; condensers; low-pressure and high-pressure heaters; feedwater tank; and steam lines. The automated diagnostic system is divided into 5 subsystems, each containing a measuring unit controlled by a PC 286 computer. These computers are included in a LAN network with a PC 386 master computer. The software consists of 3 components, viz. ONSPEC for controlling the measuring unit, data evaluation and organization and for intercommunication within the LAN; diagnostic software for the diagnostic tests, of which a total of 23 are included; and communication software for transmitting the diagnostic test results to the unit control room and also for transmitting data from accurate sensors to the information computer system for technico-economic calculations. The whole system is open to future supplementing with additional software, diagnostic tests or diagnostic subsystems. (P.A.). 1 fig., 3 refs

Retrofitting of NPP Computer systems

International Nuclear Information System (INIS)

Pettersen, G.

1994-01-01

Retrofitting of nuclear power plant control rooms is a continuing process for most utilities. This involves introducing and/or extending computer-based solutions for surveillance and control as well as improving the human-computer interface. The paper describes typical requirements when retrofitting NPP process computer systems, and focuses on the activities of Institute for energieteknikk, OECD Halden Reactor project with respect to such retrofitting, using examples from actual delivery projects. In particular, a project carried out for Forsmarksverket in Sweden comprising upgrade of the operator system in the control rooms of units 1 and 2 is described. As many of the problems of retrofitting NPP process computer systems are similar to such work in other kinds of process industries, an example from a non-nuclear application area is also given

The Chernobyl NPP decommissioning: Current status and alternatives

International Nuclear Information System (INIS)

Mikolaitchouk, H.; Steinberg, N.

1996-01-01

After the Chernobyl accident of April 26, 1986, many contradictory decisions were taken concerning the Chernobyl nuclear power plant (NPP) future. The principal source of contradictions was a deadline for a final shutdown of the Chernobyl NPP units. Alterations in a political and socioeconomic environment resulted in the latest decision of the Ukrainian Authorities about 2000 as a deadline for a beginning of the Chernobyl NPP decommissioning. The date seems a sound compromise among the parties concerned. However, in order to meet the data a lot of work should be done. First of all, a decommissioning strategy has to be established. The problem is complicated due to both site-specific aspects and an absence of proven solutions for the RBMK-type reactor decommissioning. In the paper the problem of decommissioning option selection is considered taking into account an influence of the following factors: relevant legislative and regulatory requirements; resources required to carry out decommissioning (man-power, equipment, technologies, waste management infrastructure, etc.); radiological and physical status of the plant, including structural integrity and predictable age and weather effects; impact of planned activities at the destroyed unit 4 and within the 30-km exclusion zone of the Chernobyl NPP; planed use of the site; socio-economic considerations

Programmes design for Bohunice NPP personnel other than control room operators

International Nuclear Information System (INIS)

Kalincik, L.

2002-01-01

This paper deals with project development of training programmes for non-licenced NPP personnel-masters, field operators, maintenance and technical supporting personnel. The programme development focuses on the part stage and on the job training at NPP. Bohunice NPP belongs to plants with higher specific number of personnel per installed power capacity. This factor also influenced the choice of programmes design. Undermentioned procedure is one of various approaches to SAT exploitation for training programmes design. (author)

Radioactive waste problems in the Kozloduy NPP

Energy Technology Data Exchange (ETDEWEB)

Videnov, N; Stanchev, V [Kombinat Atomna Energetika, Kozloduj (Bulgaria)

1996-12-31

An average volume of 1400 m{sup 3} a year of solid radioactive waste (RAW) is generated in the Kozloduy NPP. The adopted waste processing sequence is collection, sorting and compaction with a 1000 tons force providing decrease in volume by factor of 15. A temporary storage facility at the Kozloduy NPP is licensed by ISUAE and CPPUAE. The treatment of liquid wastes is performed by Westinghouse formula and a technology using an automated solidification system. Contaminated oils are burned using an oil incinerator. A special 2-year programme for RAW management is being developed.

Radioactive waste problems in the Kozloduy NPP

International Nuclear Information System (INIS)

Videnov, N.; Stanchev, V.

1995-01-01

An average volume of 1400 m 3 a year of solid radioactive waste (RAW) is generated in the Kozloduy NPP. The adopted waste processing sequence is collection, sorting and compaction with a 1000 tons force providing decrease in volume by factor of 15. A temporary storage facility at the Kozloduy NPP is licensed by ISUAE and CPPUAE. The treatment of liquid wastes is performed by Westinghouse formula and a technology using an automated solidification system. Contaminated oils are burned using an oil incinerator. A special 2-year programme for RAW management is being developed

Knowledge management during decommissioning of Chornobyl NPP

International Nuclear Information System (INIS)

Gora, A.D.; Kuchinskij, V.K.; Stel'makh, D.A.; Tsivun, T.A.

2010-01-01

The article deals with issues on knowledge management during decommissioning by the example of the Chornobyl NPP. This includes how the duration of decommissioning stage, change in organization goal and final state of the site influence on human resources and knowledge management system. The main attention is focused on human assets and intellectual strength of Chornobyl NPP. Mathematical dependencies are proposed to substantiate numerical values. An analysis is given for the current situation, and forecast estimates for values dynamics is performed. The conclusion gives solutions on providing experienced staff in the future.

Shock absorber in Ignalina NPP

International Nuclear Information System (INIS)

Bulavas, A.; Muralis, J.

1996-09-01

Theoretical calculation and experimental analysis of models of shock absorber in Ignalina NPP is presented. The results obtained from the investigation with model of shock absorber coincide with the theoretical calculation. (author). 2 figs., 3 refs

Framatome Contribution to Chinese NPP Development and Standardization

International Nuclear Information System (INIS)

Charbonneau, S.

1996-01-01

First discussions in 1978 between Framatome and Chinese authorities about the supply of an NPP were successfully concluded in 1986 by the signature of the supply contracts (nuclear islands, conventional islands, nuclear fuel assemblies, and project management assistance) for the Daya Bay NPP. Since then teams of engineers and technicians from Framatome and other French companies, and from relevant Chinese institutes and agencies have gotten to know each other better and have deepened their relationships

Computerized systems of NPP operators support. (Psychological problems)

International Nuclear Information System (INIS)

Mashin, V.A.

1995-01-01

Operator psychological problems arising in the work with NPP operators support computerized systems (OSCS) are considered. The conclusion is made that the OSCS intellectual application will bring the operator into dangerous dependence on his computerized assistant. To avoid this danger it is necessary by creation of the OSCS to divide specially the tasks areas of the operator and OSCS in order to assure the active role of the operator in the NPP control

Morbidity with temporary disability in Kozloduy NPP workers

International Nuclear Information System (INIS)

Dobreva, B.; Novkirishki, V.

1993-01-01

Changes with time in indicators of disease incidence with temporary disability in Kozloduy NPP personnel have been studied for the period 1974-1991. The data were compared with those for 'Sofia-Iztok' TPP. The causes contributing to formation of the indicators of frequency, severity, and average duration were examined. No temporary disability because of radiation exposure has been recorded. As a whole, less temporary disability has been found at NPP than at TPP. (author)

Detection and elimination of the electromagnetic interferences in the neutron flux measurement circuit, Source Range; Deteccion y eliminacion de interferencias electromagneticas en el circuito de medicion de flujo neutronico, rango de fuente

Energy Technology Data Exchange (ETDEWEB)

Acosta, J. M.; Esguivillas, L.; Valle, J. L.

2010-07-01

This paper compiles an experience in Asco I Nuclear Power Plant about electromagnetic interferences associated to the neutron flux measurement system, Source Range Asco I NPP. The circuit affected is the proportional detector (BF3) located outside the reactor vessel to measure the neutron leakage in shutdown and in start-up.

Operative modes of the primary circuit degasser of Atucha II N.P.P

International Nuclear Information System (INIS)

Rodriguez, Ivanna; Contino, Maximiliano; Chocron, Mauricio; Duca, Jorge

2012-09-01

Atucha II (N.A.S.A., Buenos Aires Province, Argentina) is a Pressurized Vessel Heavy Water Reactor designed by Siemens with a capacity of 740 MWe. After a long delay in construction the plant is close to the commissioning and among the many task that are carried out, chemistry and operation of devices related to it are under consideration [1]. As it is known, Hydrogen or Deuterium dosing has the purpose of both: limitation of the water radiolysis and to provide an appropriate reductive media for the structural materials, mainly stainless steel, A800 and Zr-4. Dealing with a heavy water plant, it is critical to determine whether it is necessary to add D 2 or if it is feasible to dose H 2 , by considering heavy water degradation and heavy water upgrading system capability. Those aspects have been previously analyzed and presented [2]. It is also necessary to consider blankets and venting locations that address to losses of the expensive D 2 . In the present work several alternatives of hydrogenation are presented and evaluated, considering the Degasser (D), the Volume Control Tank (TCV) and the special features of the purification and volume control system of a pressurized vessel heavy water plant where the primary circuit and moderator are partially mixed. Also the influence of venting through the pressurizer is analyzed. Conclusions are obtained in connection to (i) the maintenance of a permanent blanket of H 2 /He, 4%, in the TCV dome at a given initial pressure, (ii) The same but constant pressure to reach 0.6 ppm of H 2 in the Primary and Moderator water circuit, (iii) transients while reducing pressure in the Degasser and considering contribution of pressurizer venting, (iv) estimated contribution of the general corrosion of the system and (iv) differences if D 2 is used. (authors)

20 Years of Dukovany NPP Operation and Plans for Future

International Nuclear Information System (INIS)

Vlcek, J.

2006-01-01

NPP Dukovany (4x440MW), the first Czech nuclear power plant and a keystone of Czech Electricity Grid, in 2005 celebrated 20 years of successful operation. In my presentation I am going to speak about next areas. I will start about construction and commissioning history of Dukovany NPP, then I'll put forward what milestones of Dukovany NPP operation were accomplished, I'll say examples about our modernisation and investment activities (including replacement of IandC equipment, modifications for increasing of power and support grid services) and in the end our plans for future. (author)

NPP estimation and seasonal change research of Gansu province in northwest China

Science.gov (United States)

Han, Tao; Wang, Dawei; Hao, Xiaocui; Jiang, Youyan

2018-03-01

Based on GIS and remote sensing technology, this paper estimates the NPP of the 2015 year-round and every season of Gansu province in northwest China by using the CASA(Carnegie Ames Stanford Approach) light energy utilization model. The result shows that the total annual NPP of Gansu province gradually decline from southeast to northwest in the space, which is in accordance with the water and heat condition in Gansu province. The results show that the summer NPP in Gansu Province is the maximum in each season. The maximum value of summer NPP in Gansu Province reached 695 (gCm-2•season-1), and the maximum value was 473 in spring, and 288 in the autumn, and the NPP in the winter in Gansu province were under 60. The fluctuation range of NPP value is large, this is due to the diversity of ecosystem types in Gansu province, including desert, grassland, farmland and forest, among them, the grassland area is the largest, and the grassland type is very diverse, the grassland coverage is obviously different, especially the low coverage grassland growth is affected by precipitation and temperature and other meteorological factors obviously.

Development of NPP Safety Requirements into Kenya's Grid Codes

Energy Technology Data Exchange (ETDEWEB)

Ndirangu, Nguni James; Koo, Chang Choong [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

2015-10-15

As presently drafted, Kenya's grid codes do not contain any NPP requirements. Through case studies of selected grid codes, this paper will study frequency, voltage and fault ride through requirements for NPP connection and operation, and offer recommendation of how these requirements can be incorporated in the Kenya's grid codes. Voltage and frequency excursions in Kenya's grid are notably frequently outside the generic requirement and the values observed by the German and UK grid codes. Kenya's grid codes require continuous operation for ±10% of nominal voltage and 45.0 to 52Hz on the grid which poses safety issues for an NPP. Considering stringent NPP connection to grid and operational safety requirements, and the importance of the TSO to NPP safety, more elaborate requirements need to be documented in the Kenya's grid codes. UK and Germany have a history of meeting high standards of nuclear safety and it is therefore recommended that format like the one in Table 1 to 3 should be adopted. Kenya's Grid code considering NPP should have: • Strict rules for voltage variation, that is, -5% to +10% of the nominal voltage • Strict rules for frequency variation, that is, 48Hz to 52Hz of the nominal frequencyand.

Development of NPP Safety Requirements into Kenya's Grid Codes

International Nuclear Information System (INIS)

Ndirangu, Nguni James; Koo, Chang Choong

2015-01-01

As presently drafted, Kenya's grid codes do not contain any NPP requirements. Through case studies of selected grid codes, this paper will study frequency, voltage and fault ride through requirements for NPP connection and operation, and offer recommendation of how these requirements can be incorporated in the Kenya's grid codes. Voltage and frequency excursions in Kenya's grid are notably frequently outside the generic requirement and the values observed by the German and UK grid codes. Kenya's grid codes require continuous operation for ±10% of nominal voltage and 45.0 to 52Hz on the grid which poses safety issues for an NPP. Considering stringent NPP connection to grid and operational safety requirements, and the importance of the TSO to NPP safety, more elaborate requirements need to be documented in the Kenya's grid codes. UK and Germany have a history of meeting high standards of nuclear safety and it is therefore recommended that format like the one in Table 1 to 3 should be adopted. Kenya's Grid code considering NPP should have: • Strict rules for voltage variation, that is, -5% to +10% of the nominal voltage • Strict rules for frequency variation, that is, 48Hz to 52Hz of the nominal frequencyand

Upgrading NPP personnel. Competence and training through the systematic approach to training

International Nuclear Information System (INIS)

Mautner Markhof, F.

1998-01-01

This paper presents the reasons for acceptance of SAT (Systematic Approach to Training) as the best international practice in respect to training of NPP personnel and the differences in comparison to traditional approaches to training. The identification and evaluation of the new training needs, resources and other requirements for implementing SAT are discussed as well as new approaches and existing training capabilities and involvement of Regulatory body in training of NPP personnel. The IAEA Guidebook on NPP Personnel Training (TRS-380) was used a a basis for discussion of the mentioned topics with the emphasis on achieving the best possible training programmes for NPP personnel

Validation of S-NPP VIIRS Sea Surface Temperature Retrieved from NAVO

Directory of Open Access Journals (Sweden)

Qianguang Tu

2015-12-01

Full Text Available The validation of sea surface temperature (SST retrieved from the new sensor Visible Infrared Imaging Radiometer Suite (VIIRS onboard the Suomi National Polar-Orbiting Partnership (S-NPP Satellite is essential for the interpretation, use, and improvement of the new generation SST product. In this study, the magnitude and characteristics of uncertainties in S-NPP VIIRS SST produced by the Naval Oceanographic Office (NAVO are investigated. The NAVO S-NPP VIIRS SST and eight types of quality-controlled in situ SST from the National Oceanic and Atmospheric Administration in situ Quality Monitor (iQuam are condensed into a Taylor diagram. Considering these comparisons and their spatial coverage, the NAVO S-NPP VIIRS SST is then validated using collocated drifters measured SST via a three-way error analysis which also includes SST derived from Moderate Resolution Imaging Spectro-radiometer (MODIS onboard AQUA. The analysis shows that the NAVO S-NPP VIIRS SST is of high accuracy, which lies between the drifters measured SST and AQUA MODIS SST. The histogram of NAVO S-NPP VIIRS SST root-mean-square error (RMSE shows normality in the range of 0–0.6 °C with a median of ~0.31 °C. Global distribution of NAVO VIIRS SST shows pronounced warm biases up to 0.5 °C in the Southern Hemisphere at high latitudes with respect to the drifters measured SST, while near-zero biases are observed in AQUA MODIS. It means that these biases may be caused by the NAVO S-NPP VIIRS SST retrieval algorithm rather than the nature of the SST. The reasons and correction for this bias need to be further studied.

Influence of the CVCS Modelling on Results of the Loss of Offsite Power (LOOP) Safety Analysis for NPP Krsko

International Nuclear Information System (INIS)

Bencik, V.; Bajs, T.; Debrecin, N.

2006-01-01

A Loss of Offsite Power (LOOP) transient scenario is based on a complete loss of non-emergency AC power that results in the loss of all power to the plant auxiliaries, i.e., the Reactor Coolant Pumps (RCPs), condensate pumps, etc. An actual LOOP event would cause a loss of all feedwater, a loss of forced Reactor Coolant System (RCS) flow and a reactor trip within less than 2 seconds as a result of either loss of power to the rod cluster assembly gripper coils or any RCS flow trips. For safety analysis purposes the LOOP event is conservatively modelled as a Loss of Normal Feedwater (LONF) transient with a subsequent loss of offsite power as a result of a reactor trip. The reactor trip followed by RCP trip are delayed until a low-low Steam Generator (SG) level signal is reached. This is a more conservative scenario than the LOOP event because the least amount of SG secondary side water mass available for heat removal and the increased amount of the stored energy in the primary circuit at the time of the loss of RCS flow result. The standard LOOP safety analysis is aimed to demonstrate the natural circulation capability of the RCS to remove residual and decay heat from the core aided by Auxiliary Feedwater in the secondary system. In addition to this goal the presented work is aimed to resolve the potential safety issue resulting from the influence of the Chemical and Volume Control System (CVCS) operation during LOOP event for NPP Krsko. The potential safety concern for the LOOP analysis is that the loss of instrument air system may occur thus leading to the CVCS charging and letdown flow imbalance. A net RCS inventory addition may result with water solid pressurizer condition. Water discharge through the pressurizer relief and safety valves could lead to overpressurization of the Pressurizer Relief Tank (PRT) and rupture of the PRT rupture disks. Additional concern is that pressurizer relief and safety valves may fail to properly reseat when exposed to water relief

Public acceptance of nuclear energy in Indonesia. A traditional puppet show for NPP in Java

International Nuclear Information System (INIS)

Suyudi Soeliarno

1995-01-01

In Indonesia, activities on public relation have been carried out since the establishment of the agency responsible for research and development of atomic energy in 1958 (which later in the year 1964 became Batan, National Atomic Energy Agency), wile activities on public acceptance started 'at the end of 1985. After the Government indicated that it has to look seriously into the construction of the NPP, as from 1990, the public acceptance (PA) activities have been intensified in anticipation of the construction of the first NPP. An important part of the preparatory activities for the construction of the NPP is preparing the people, particularly those who live near the NPP site, to accept and to support the NPP program. The interdepartmental team has bee established in August 1990 consisting of representatives of several institutions, namely, Ministry of Information, Ministry of Domestic Affairs, Ministry of Defense, Land Utilization Agency, State Electricity Corporation, Office of the Minister for Population and Environment, and Batan. This team, called the 'Team on Public Acceptance of NPP', has the main task providing extensive information to the public concerning the government plan to construct nuclear power plants in Indonesia. From 1990 through the middle of 1994 the activity of the Team on Public Acceptance of NPP was focused on providing information on te NPP program to the local community leaders and the public, particularly in the districts of the NPP site in the Muria Peninsula region. Its main purpose was to precondition the people who live near the NPP site to accept the NPP in their neighbourhood without fear

NPP Boreal Forest: Consistent Worldwide Site Estimates, 1965-1995, R1

Data.gov (United States)

National Aeronautics and Space Administration — This data set provides estimates of above- and below-ground biomass, above- and below-ground NPP (ANPP and BNPP), and total NPP(TNPP) for selected North American and...

Use of NESTLE computer code for NPP transition process analysis

International Nuclear Information System (INIS)

Gal'chenko, V.V.

2001-01-01

A newly created WWER-440 reactor model with use NESTLE code is discussed. Results of 'fast' and 'slow' transition processes based on it are presented. This model was developed for Rovno NPP reactor and it can be used also for WWER-1000 reactor in Zaporozhe NPP

About choosing the power unit of NPP

International Nuclear Information System (INIS)

Alekseev, P.N.; Mordashev, V.M.; Proshkin, A.A.; Stukalov, V.A.; Subbotin, S.A.; Tsibul'skij, V.F.; Chernilin, Yu.F.

2008-01-01

The present-day domestic nuclear power industry faces the necessity to make both process and economy related decisions. The mentioned decisions should cover all the aspects of the nuclear power complex. In particular, as of now, no substantiation of the present-day and the future requirements for the power unit of the WWER and fast reactor NPPs is available. The choice of the unit power of an NPP should involve consideration of all factors and should not be boiled down to the efforts to ensure the minimization of the investment and the operation constituents of the electric power generation costs. The aim of the present paper was to ensure elaboration of the recommendations to substantiate the optimal unit power of NPP power units based on the analysis of various factors to design, to construct and to operate an NPP (investment, time of construction, the unscheduled shutdown losses, the unification, the fabrication quality, the accident damage, etc.), and the electrical network potentialities and the regional electric power demands [ru

Implementing the Environmental Management System ISO 14001 at the Cernavoda NPP Unit 1

International Nuclear Information System (INIS)

Jelev, Adrian

2003-01-01

An environmental management plan (EMP) has been developed for the Cernavoda NPP Unit 1. It contains the necessary components for identification and management of the environmental aspects of NPP. The environmental policy of the 'Nuclearelectrica' National Society and the associated EMP are the basis for the Environment Management System that will be implemented at Cernavoda NPP. The final step of this process will be the ISO 14001 certification. This paper points out to the main aspects concerning the implementation of the ISO 14001 system at Cernavoda NPP Unit 1. (author)

Temelin NPP commissioning experiences

International Nuclear Information System (INIS)

Hanus, V.

2002-01-01

The Building Permit for the Temelin NPP with four VVER units was issued in 1986, which is a long time ago. Since then, however, was taken a route that is very different from what anybody imagined. Described are the legislative and design changes and given is a current condition of the power plant

ASSET experience at Paks NPP

International Nuclear Information System (INIS)

Szabo, I.

1997-01-01

At Paks NPP special attention has been paid to international reviews since the very beginning of operation. Several international teams visited Paks in order to provide independent assessment of plant performance, conditions and safety. Paks NPP Management has the further intention to invite international reviews regularly (yearly) in the future as well. The experience gained during these reviews helped to establish a unified process of preparation for the reviews, performing them and handling the results. The Safety Department is in charge of organization of the whole process. All these reviews have their specific features and they are focused on different areas. The ASSET reviews provides the assessment of plant performance and safety through the analysis of safety significant events, which have occurred at the nuclear power plant. This approach makes this review specific and different from the other ones

ASSET experience at Paks NPP

Energy Technology Data Exchange (ETDEWEB)

Szabo, I [Operational Safety Dept., Paks NPP, Paks (Hungary)

1997-10-01

At Paks NPP special attention has been paid to international reviews since the very beginning of operation. Several international teams visited Paks in order to provide independent assessment of plant performance, conditions and safety. Paks NPP Management has the further intention to invite international reviews regularly (yearly) in the future as well. The experience gained during these reviews helped to establish a unified process of preparation for the reviews, performing them and handling the results. The Safety Department is in charge of organization of the whole process. All these reviews have their specific features and they are focused on different areas. The ASSET reviews provides the assessment of plant performance and safety through the analysis of safety significant events, which have occurred at the nuclear power plant. This approach makes this review specific and different from the other ones.

Analysis of an NPP Structure subjected to Vibrations Induced from Airplane Crashes

International Nuclear Information System (INIS)

Noh, Sang Hoon; Kim, Yong Soo; Kim, Chong Hak

2009-01-01

After the terrorists' attacks with civilian airplanes on September 11, 2001, special attention has been paid to the potential for an airplane crash into a Nuclear Power Plant (NPP) as a man-made hazard. An airplane crash (APC) into an NPP has the potential to damage the roofs and walls of these structures, as well as other systems and components such as pipelines, electric motors, power supplies, power cables of electricity transmission that are important for safety. Therefore, an evaluation of the structural response to an APC is important for the safety of NPPs to be confirmed. A structural integrity analysis was carried out focusing on the vibration effects of an APC on an NPP structure. The NPP structure under consideration has been conceptually redesigned based on APR1400 to have double containments for the purpose of a feasibility study to meet European requirements. The finite element method was used for the structural analysis of the NPP, and the computer code ABAQUS was employed for this analysis

A Radiological Survey Approach to Use Prior to Decommissioning: Results from a Technology Scanning and Assessment Project Focused on the Chornobyl NPP

Energy Technology Data Exchange (ETDEWEB)

Milchikov, A.; Hund, G.; Davidko, M.

1999-10-20

The primary objectives of this project are to learn how to plan and execute the Technology Scanning and Assessment (TSA) approach by conducting a project and to be able to provide the approach as a capability to the Chernobyl Nuclear Power Plant (ChNPP) and potentially elsewhere. A secondary objective is to learn specifics about decommissioning and in particular about radiological surveying to be performed prior to decommissioning to help ChNPP decision makers. TSA is a multi-faceted capability that monitors and analyzes scientific, technical, regulatory, and business factors and trends for decision makers and company leaders. It is a management tool where information is systematically gathered, analyzed, and used in business planning and decision making. It helps managers by organizing the flow of critical information and provides managers with information they can act upon. The focus of this TSA project is on radiological surveying with the target being ChNPP's Unit 1. This reactor was stopped on November 30, 1996. At this time, Ukraine failed to have a regulatory basis to provide guidelines for nuclear site decommissioning. This situation has not changed as of today. A number of documents have been prepared to become a basis for a combined study of the ChNPP Unit 1 from the engineering and radiological perspectives. The results of such a study are expected to be used when a detailed decommissioning plan is created.

A Radiological Survey Approach to Use Prior to Decommissioning: Results from a Technology Scanning and Assessment Project Focused on the Chernobyl NPP

International Nuclear Information System (INIS)

Milchikov, A.; Hund, G.; Davidko, M.

1999-01-01

The primary objectives of this project are to learn how to plan and execute the Technology Scanning and Assessment (TSA) approach by conducting a project and to be able to provide the approach as a capability to the Chernobyl Nuclear Power Plant (ChNPP) and potentially elsewhere. A secondary objective is to learn specifics about decommissioning and in particular about radiological surveying to be performed prior to decommissioning to help ChNPP decision makers. TSA is a multi-faceted capability that monitors and analyzes scientific, technical, regulatory, and business factors and trends for decision makers and company leaders. It is a management tool where information is systematically gathered, analyzed, and used in business planning and decision making. It helps managers by organizing the flow of critical information and provides managers with information they can act upon. The focus of this TSA project is on radiological surveying with the target being ChNPP's Unit 1. This reactor was stopped on November 30, 1996. At this time, Ukraine failed to have a regulatory basis to provide guidelines for nuclear site decommissioning. This situation has not changed as of today. A number of documents have been prepared to become a basis for a combined study of the ChNPP Unit 1 from the engineering and radiological perspectives. The results of such a study are expected to be used when a detailed decommissioning plan is created

Safety Culture Survey in Krsko NPP

International Nuclear Information System (INIS)

Strucic, M.; Bilic Zadric, T.

2008-01-01

The high level of nuclear safety, stability and competitiveness of electricity production, and public acceptability are the main objectives of Krsko Nuclear Power Plant. This is achievable only in environment where strong Safety Culture is taking dominant place in the way how employees communicate, perform tasks, share their ideas and attitudes, and demonstrate their concern in all aspects of work and coexistence. To achieve these objectives, behaviour of all employees as well as specific ethical values must become more transparent and that must arise from the heart of organization. Continuous ongoing and periodic self assessments of Safety Culture in Krsko NPP present major tools in implementation process of this approach. Benefits from Periodic interdisciplinary focused self assessment approach, which main intention is finding the strengths and potential areas for improvements, was used second time to assess the area of Safety Culture in Krsko NPP. Main objectives of self assessment, performed in 2006, were to increase the awareness of the present culture, to serve as a basis for improvement and to keep track of the effects of change or improvement over a longer period of time. For the purpose of effective self assessment, extensive questionnaire was used to obtain information that is representative for whole organization. Wide range of questions was chosen to cover five major characteristics of safety culture: Accountability for safety is clear, Safety is integrated into all activities, Safety culture is learning-driven, Leadership for safety is clear and Safety is a clearly recognized value. 484 Krsko NPP employees and 96 contractors were participated in survey. 70-question survey provided information that was quantified and results compared between groups. Anonymity of participant, as well as their willingness to contribute in this assessment implicates the high level of their openness in answering the questions. High number of participant made analysis of

Ecological radiation monotoring in NPP region, aims and tasks

International Nuclear Information System (INIS)

Egorov, Yu.A.

1986-01-01

Aims and tasks of ecological radiation monitoring in the NPP region are discussed. The aims of monitoring are: to determine possible sequences of NPP radioactive release effects on ecosystems, taking place on the background of chemical and thermal pollution to develop standard of radiation effect on ecosystems; the aims includes also obtaining of information for forecasting and evaluating long-term radiation effects, establishment of factors characterizing the ecosystem state, establishment of a combined effect of radioactive wastes with chemical and thermal ones. Finally, the aim of monitoring consists in providing the natural object conservation in the NPP region under optimal operation conditions. Thus it is necessary to solve the following problems: to observe systematically release, transport and transformation, when transporting radioactive and chemical contaminants in terrestial and aquatic biocenoses, as well as injection and transport in them of waste heat; to observe systematically the natural physico-chemical, chemico-biological processes affecting the injection and transport of contaminants in ecosystem components; to observe systematically the natural and, probably, antropogenic processes; to carry out systematically observations of the ecosystem state in the NPP region and eco-systems-monitors

Safety aspects of NPP ageing

International Nuclear Information System (INIS)

1995-01-01

Preparation of safety practices on assessment and management of aging of major NPP components important to safety, CRP on management of aging of concrete containment buildings, CRP on management of aging of in-containment instrumentation and control cables are outlined

Qualification of NPP operations personnel

International Nuclear Information System (INIS)

Wang Jiao.

1987-01-01

Competence of personnel is one of the important problems for safety operation of nuclear power plant. This paper gives a description of some aspects, such as the administration of NPP, posts, competence of personnel, training, assessing the competence and personnel management

Conceptual Design of a Combined Power Generation Unit at the NPP Seaside

International Nuclear Information System (INIS)

Cha, Kyung H.

2011-01-01

In order to improve operational performance, an undersea tunnel is being utilized for in-taking and out-taking seawater as coolant in Nuclear Power Plant (NPP). This paper describes a Combined solar-wind-wave Power Generation Unit (CPGU) to be specialized for in-taking and out-taking seawater as coolant in NPP. Accordingly, the purpose of the CPGU is twofold: one is to contain some tunnels to be maintained on the bottom of the CPGU body in order to in-take and out-take coolant water, and the other is to generate a combined power at the NPP seaside. Fig. 1 shows the conceptual CPGU to be configured at the NPP seaside

Algorithmization of problems on the personnel information support in the automatic chemical control systems at NPP

International Nuclear Information System (INIS)

Vilkov, N.Ya.; Kryukov, Yu.V.; Cheshun, A.V.

2001-01-01

When elaborating software for the standard algorithms of the information support of the efficient control (keeping) of water chemistry operation (WCO) at the NPP power units one introduces an approach when the systems of chemical control are realized as the systems of quality control of in-loop physical and chemical processes gathering force in the course of time. Elaboration of algorithms to proceed data of the operational chemical control seeks for elaboration of the statistic procedures to detect anomalies of the processes at the early stages of their development more efficient in contrast to the standard procedures of control. The introduced procedure is used in the demonstration model of the system for diagnostics of some typical reasons of violation of the first circuit WCO of WWER-1000 power units [ru

ICEMENERG technologies of water treatment applied at Cernavoda NPP Unit 1

International Nuclear Information System (INIS)

Stanca, Angela; Bolma, Aurelia; Serbanescu, Agnes; Raducanu, Alice

2002-01-01

The paper presents the ICEMENERG technologies for water treatment applied at Cernavoda Unit 1, the treatment of the additional water for power steam generators and the chemical treatment of cooling system water. The requirements for quality of water totally demineralized as imposed by the AECL-ANSALDO consortium are as following: electrical conductivity, < 0.2 mS/cm; total silicon, <0.02 mg/L; ionic silicon, <0.01 mg/L; sodium, < 0.05 mg/L; TOC, <0.300 mg/L. These requirements raise rather difficult problems to be solved because the raw water source in case of Cernavoda NPP is Danube River which presents a raising trend of organic and inorganic contamination. Accordingly, experiments at laboratory scale reproducing the entire technological flow were conducted. The following operations were studied: pretreatment with limewash, ferric chloride (with and without coagulation additives); demineralization with ion exchangers of Purolite and Amberlite types. The system consisted of a cationic stage, formed of an strongly acid step with countercurrent recovery and an anionic stage formed of two steps, namely, a weakly basic step and a strongly basic step with recovery inserted; finishing on mixed bed. The paper presents also the chemical treatment/conditioning of the cooling loop of turbine condenser. The Cernavoda NPP cooling system is an open system with a single flow of cooling water comprising two systems, namely, the circulation water system ensuring the steam condenser cooling and the servicing water system ensuring the cooling of heat exchangers in the recirculated water circuit (RCWS), the turbine oil coolants, the coolants of auxiliary steam as well as the emergency core cooling system. Studies were conducted to ensure the chemical conditioning of the raw water from Danube River, particularly, to destroy and remove the shells, the algae and other components. Finally, the following four steps of conditioning the water of the cooling system are summarized: 1

PTS assessment - The basis of life time evaluation at NPP Paks

International Nuclear Information System (INIS)

Elter, J.; Oszwald, F.; Ratkay, S.; Fekete, T.; Gillemot, F.; Marothy, L.

1997-01-01

Plant specific PTS analysis at NPP Paks was performed in the frame of the AGNES (Advanced General New Evaluation of Safety) project. NPP Paks belongs to the second generation of the WWER-440/213 NPP-s. To verify the safety during transient events and predict the lifetime of the RPV-s several transient cases have been analyzed. The paper summarizes: The general scheme elaborated for the assessment; the safety philosophy used; the applied and available codes and methods; the ongoing and planned developments. (author). 8 refs, 3 figs, 1 tab

PTS assessment - The basis of life time evaluation at NPP Paks

Energy Technology Data Exchange (ETDEWEB)

Elter, J; Oszwald, F; Ratkay, S [NPP Paks (Hungary); Fekete, T; Gillemot, F; Marothy, L [Atomic Energy Research Inst., Budapest (Hungary)

1997-09-01

Plant specific PTS analysis at NPP Paks was performed in the frame of the AGNES (Advanced General New Evaluation of Safety) project. NPP Paks belongs to the second generation of the WWER-440/213 NPP-s. To verify the safety during transient events and predict the lifetime of the RPV-s several transient cases have been analyzed. The paper summarizes: The general scheme elaborated for the assessment; the safety philosophy used; the applied and available codes and methods; the ongoing and planned developments. (author). 8 refs, 3 figs, 1 tab.

Top level risk study for units 1 to 4 at NPP Kozloduy

International Nuclear Information System (INIS)

Shishkova, I.

1997-01-01

The first Top Level Study of NPP Kozloduy Units 1/4 was started in 1991 and completed in March 1992 by BEQE. The Primary objective of the project was to provide in a short term a tool for quantified comparison of the relative risk benefits that various design or operational modifications would have if implemented on NPP Kozloduy Units 1/4. This original version of the Study was reviewed by the IAEA who agreed in general with the conclusions indicating that the report provides valuable insights which should be used in the decision making process. The IAEA made suggestion for some changes. These comments were taken into account in the subsequent version. In early 1994 the new version was issued. The objective of this second project, in addition to revising the original study to reflect the IAEA comments, was to address the potential benefits from further improvements at NPP Kozloduy. The work on the second version was going on in parallel with the activities carried out in the mainframe of several NPP Kozloduy Units 1/4 Upgrading Program (WANO Six-Month Program, Program for the NPP Kozloduy Units 1-4 Upgrading, Twinning Program, etc.). And at last, a Top-Level Probabilistic Safety Study was carried out by EQE - Bulgaria and completed early in 1995 at the request of NPP Kozloduy. The objective of the project was the contribution of the different activities performed in the mainframe of the Program for the NPP Kozloduy Units 1-4 Safety Upgrading in the overall safety improvement to be assessed. 3 figs, 1 tab

NPP operation and modern high technologies

International Nuclear Information System (INIS)

Kuznetsov, V.V.

1992-01-01

Examples are considered of modern high technology introduction into daily practice of NPP operation, namely: satellite communication systems, robots, non-destructive testing, optical-fiber techniques, laser measuring means and others

Design of NPP of new generation being constructed at the Novovoronezh NPP site

International Nuclear Information System (INIS)

Afrov, A.; Berkovich, V.; Generalov, V.; Dragunov, Yu.; Krushelnitsky, V.

1999-01-01

The design of a new generation NPP is described, underscoring advances in physical attributes and passive safety systems based on experiences with earlier designs at operating NPPs. This paper elaborates on systems for handling and storing radioactive wastes, on refinements in containment measures and on experimental and analytic validation of critical design factors. (author)

Equipment reliability improvement process; implementation in Almaraz NPP and Trillo NPP

International Nuclear Information System (INIS)

Risquez Bailon, Aranzazu; Gutierrez Fernandez, Eduardo

2010-01-01

The Equipment Reliability Improvement Process (INPO AP-913) is a non-regulatory process developed by the US Nuclear Industry for improving Plants Availability. This Process integrates and coordinates a broad range of equipment reliability activities into one process, performed by the Plant in a non-centralized way. The integration and coordination of these activities will allow plant personnel to evaluate the trends of important station equipment, develop and implement long-term equipment health plans, monitor equipment performance and condition, and make adjustments to preventive maintenance tasks and frequencies based on equipment operating experience, if necessary, arbitrating operational and design improvements, to reach a Failure-free Operation. This paper describes the methodology of Equipment Reliability Improvement Process, being focused on main aspects of the implementation process, relating to the scope and establishment of an Equipment Reliability Monitoring Plan, which should include and complement the existing mechanisms and organizations in the Plant to monitor the condition and performance of the equipments, with the common aim of achieving an operation free of failures. The paper will describe the tools that Iberdrola Ingenieria has developed to support the implementation and monitoring of the Equipment Reliability Improvement Process, as well as the results and lessons learned from its implementation in Almaraz NPP and Trillo NPP. (authors)

Dukovany NPP maintenance management

International Nuclear Information System (INIS)

Siegel, F.

2005-01-01

Maintenance planning and management for the technological equipment of the Dukovany NPP are described. A Maintenance Control and Evaluation System has been developed and is in use to help manage the complex maintenance issue. Practical examples of outputs of the System, with a comprehensive use of the cost, reliability and safety related data, are presented. (author)

Core design methodology and software for Temelin NPP

International Nuclear Information System (INIS)

Havluj, F; Hejzlar, J.; Klouzal, J.; Stary, V.; Vocka, R.

2011-01-01

In the frame of the process of fuel vendor change at Temelin NPP in the Czech Republic, where, starting since 2010, TVEL TVSA-T fuel is loaded instead of Westinghouse VVANTAGE-6 fuel, new methodologies for core design and core reload safety evaluation have been developed. These documents are based on the methodologies delivered by TVEL within the fuel contract, and they were further adapted according to Temelin NPP operational needs and according to the current practice at NPP. Along with the methodology development the 3D core analysis code ANDREA, licensed for core reload safety evaluation in 2010, have been upgraded in order to optimize the safety evaluation process. New sequences of calculations were implemented in order to simplify the evaluation of different limiting parameters and output visualization tools were developed to make the verification process user friendly. Interfaces to the fuel performance code TRANSURANUS and sub-channel analysis code SUBCAL were developed as well. (authors)

Main principles of the Chernobyl' NPP zone development

International Nuclear Information System (INIS)

Ignatenko, E.I.; Komarov, V.I.; Zverkov, V.V.; Proskuryakov, A.G.

1989-01-01

It is suggested to divide the Chernobyl' NPP zone into two parts, which are the alienation and evacuation (buffer) zones. The alienation zone includes the areas with greatest contamination around the Chernobyl' NPP. The population residence in this zone is forbidden. The watching method of working with short-time personnel residence is suggested to be used in this zone. The buffer zone is the territory out of the alienation zone boundaries including all settlements, from which the population is evacuated. Constant residence is permitted in the buffer zone for persons 50 and more years old with introduction of restrictions for diet and residence organization. The production activity in this zone includes operation of three units of the Chernobyl' NPP, works with the Ukrytie object and researches. Operations connected with radioactive waste processing and redisposal from places of storage is not recommended to be done. It is suggested to develop methods for local radioactive waste processing

NPP Temelin. Status of safety improvements

International Nuclear Information System (INIS)

1999-01-01

The WWER-1000 Temelin NPP under construction has been subjected as other NPPs of the same type to numerous project reviews resulting in quite a number of recommendations for design changes. Results of the IAEA mission to review the resolution of WWER-1000 safety issues at Temelin NPP are cited in this paper. The main conclusions emphasize that a combination of eastern and western technology and practices led to safety improvements in comparison with the international practices. Plant managers are clearly committed to implementation of operational programs which are consistent with effective western operational safety practices. Considerable effort remains to bring planned programs to successful implementation, in particular in meeting the need to foster strong safety culture among all personnel

A comparison of the Kozloduy NPP and Temelin NPP I and C projects

International Nuclear Information System (INIS)

Cook, B.M.

2004-01-01

Because Kozloduy NPP and Temelin NPP are both VVER 1000 plants of roughly the same vintage, they are very similar in design. However, from the viewpoint of their I and C modernization projects, there are significant differences between these plants. Some of these differences stem from the evolution of I and C technology over the relatively short period between the two projects. Other differences arise from the fact that the Kozloduy project is a phased upgrade of the I and C systems in an operating plant while the Temelin project was a 'one time' installation of the entire plant I and C system. This paper discusses these differences as well as trends in the nuclear I and C field that will shape the industry in the future. In addition to technology evolution, the comparative advantages or problems in phased upgrade versus 'one time' installations are discussed. Conclusions drawn provide insight for the planning of future I and C upgrades in VVERs and other types of nuclear power plants. (author)

The safety of Ignalina NPP and ecological danger in public opinion of inhabitants of Daugavpils region

International Nuclear Information System (INIS)

Peipinia, O.

1998-01-01

Inquest of Daugavpils' region pointed to a big anxiety for ecological danger of Ignalina NPP by inhabitants and experts. Absolute majority of respondents (73-78% inhabitants and 68-82% experts) apprehend the NPP as very dangerous and dangerous. More than half of respondents apprehend the dangerous increased during last two-three years. It is because no one has a good reference about situation, because tragic al Chernobyl NPP burst was on. The anxiety increases if the respondent lives nearer of NPP. Inhabitants of Daugavpils and it's region wants the better reference about situation, about future of Ignalina NPP after 2010 year, about securities means in case of NPP burst. (author)

Decommissioning of NPP A1 - HWGCR type

International Nuclear Information System (INIS)

Burclova, J.

1998-01-01

Prototype nuclear power plant A-1 located at Jaslovske Bohunice, was a HWGCR with channel type reactor KS 150 (refuelling during operation) and capacity of 143 MWe. Single unit has been constructed with reactor hall building containing reactor vessel, heavy water system and equipment for spent fuel handling. Another compartment of main building contents coolant system piping, six steam generators and six turbo compressors, the turbine hall was equipped by three turbines. Unit also shares liquid radwaste treatment and storage buildings and ventilation systems including chimney. It started operation in 1972 and was shutdown in 1977 after primary coolant system integrity accident. In 1979 a final decision was made to decommission this plant. The absence of waste treatment technologies and repository and not sufficient storage capacity affected the planning and realization of decommissioning for NPP A-1. The decommissioning policy for the first stage is for lack of regulations based on 'case by case' strategy. For these reasons and for not existence of Decommissioning Found until 1995 the preferred decommissioning option is based on differed decommissioning with safe enclosure of confinement. Transfer of undamaged spent fuel cooled in organic coolant to Russia was finished in 1990. It was necessary to develop new technology for the damaged fuel preparation for transport. The barriers check-up and dismantling of secondary circuit and cooling towers was performed during 1989/90. The complex plan for the first phase of A-1 decommissioning - the status with treated operational radwaste, removed contamination and restored treated waste and spent fuel (in case of interruption of transfer to Russia) was developed in 1993-1994. Under this project bituminization of all liquid operational radwaste (concentrates) was performed during 1995/96, vitrification of inorganic spent fuel coolant started at 1996, decontamination of spent fuel pool coolant occurs (under AEA Technology

Flow accelerated corrosion and its control measures for the secondary circuit pipelines in Indian nuclear power plants

International Nuclear Information System (INIS)

Kain, Vivekanand; Roychowdhury, S.; Mathew, Thomas; Bhandakkar, Atul

2008-01-01

A plain carbon steel feeder pipeline in the secondary circuit failed downstream of a flow measurement device (orifice meter) during operation at nuclear power plant. A detailed failure analysis done on the failed pipeline is described in this paper. The results established the fine surface pattern of 'Horseshoe pits' at the affected regions. X-ray diffraction analysis on the samples far from the failed regions showed presence of magnetite but on the sample from the failed region showed peaks due to base metal only, indicating dissolution of the oxide. Thickness profiling of the pipeline indicated reduction of thickness from the design 7.62 mm to a minimum of 0.4-1.4 mm at the location of the failure. These observations are characteristic of single phase flow accelerated corrosion. This paper details the extent of flow accelerated corrosion in various Indian power plants and the remedial measures for replacement and possible design and water chemistry changes to combat it

Safety improvement and results of commissioning of Mochovce NPP WWER 440/213

International Nuclear Information System (INIS)

Lipar, M.

1998-01-01

Mochovce NPP is the last one of this kind and compared to its predecessors, it is characterized by several modifications which contribute to the improvement of the safety level. In addition based on Nuclear Regulatory Authority requirements and based on documents: - IAEA - Safety Issues and their ranking for NPP WWER 440/213, - IAEA - Safety Improvement of Mochovce NPP Project Review Mission, - Riskaudit - Evaluation of the Mochovce NPP Safety Improvements. Additional safety measures have been implemented before commissioning. The consortium EUCOM (FRAMATOME - SIEMENS), SKODA Praha, ENERGOPROJEKT Praha, Russian organizations and VUJE Trnava Nuclear Power Plants research institute were selected for design and implementation of the safety measures. The papers summarized, safety requirements, safety measures implemented, results of commissioning and results of safety analysis report evaluation. (author)

Operation experience of the advanced fuel assemblies at Unit 1 of Volgodonsk NPP within four fuel cycles

International Nuclear Information System (INIS)

Vasilchenko, I.; Kobelev, S.; Kushmanov, S.

2006-01-01

The first commissioning of Volgodonsk NPP Unit 1 with standard reactor WWER-1000 (project V-320) was in 2001. The reactor core, starting from the first fuel charge, was arranged completely with Advanced Fuel Assemblies (AFAs). In this way, it is possible to obtain the experience in startup and operation of the core, completely arranged with AFAs, and also to get a possibility of performing the comprehensive check for justification of newly commissioned units and justification of design solutions accepted in the design of reactor core for Taiwan NPP, Bushehr NPP and Kudankulam NPP. The first fuel charge of the Volgodonsk NPP Unit 1 is a reference and unified for Tiawan NPP (V-428), Bushehr NPP (V-446), Kudankulam NPP(V-412) with small differences caused by design features of RP V-320. The first core charge of Unit 1 of Volgodonsk NPP was arranged of 163 AFAs, comprising 61 CPS ARs and 42 BAR bundles. The subsequent fuel charges were arranged of AFAs with gadolinium oxide integrated into fuel instead of BAR. By 2005 the results of operation of the core at Unit 1 of Volgodonsk NPP during four fuel cycles showed that AFA is sufficiently reliable and serviceable. The activity of the primary coolant of the Volgodonsk NPP is at stable low level. During the whole time of the core operation of the Volgodonsk NPP Unit 1 no leaky AFAs were revealed. The modifications of the internals, made during pre-operational work, are reasonable and effective to provide for fuel mechanical stability in the course of operation. The modifications, made in AFA structure during operation of the Volgodonsk NPP Unit 1, are aimed at improving the service and operational reliability of its components. Correctness of the solutions taken is confirmed by AFAs operation experience both at the Volgodonsk NPP, and at other operating Russian NPPs

Improving the ALUeS diagnostic system for determining the coolant leak place from the WWER-440 primary circuit

International Nuclear Information System (INIS)

Markosyan, G.R.; Petrosyan, V.G.; Shakhverdyan, S.V.; Aslanyan, M.A.

2000-01-01

The new algorithm for localizing the leakage from the WWER-440 primary circuit, intended for operation in the Siemens ALUeS system, is proposed. The results of the algorithm realization in the leakage control system (the ALUeS system copy), installed at the Armenian NPP power unit-2, are presented. The leakage localization algorithm proposed was tested in other experiments. The leakage position in the majority of cases is determined exactly. Small (up to 5 m) deviations, the cause whereof were incorrect readings of the transducers, were observed [ru

Conducting water chemistry of the secondary coolant circuit of VVER-based nuclear power plant units constructed without using copper containing alloys

Science.gov (United States)

Tyapkov, V. F.

2014-07-01

The secondary coolant circuit water chemistry with metering amines began to be put in use in Russia in 2005, and all nuclear power plant units equipped with VVER-1000 reactors have been shifted to operate with this water chemistry for the past seven years. Owing to the use of water chemistry with metering amines, the amount of products from corrosion of structural materials entering into the volume of steam generators has been reduced, and the flow-accelerated corrosion rate of pipelines and equipment has been slowed down. The article presents data on conducting water chemistry in nuclear power plant units with VVER-1000 reactors for the secondary coolant system equipment made without using copper-containing alloys. Statistical data are presented on conducting ammonia-morpholine and ammonia-ethanolamine water chemistries in new-generation operating power units with VVER-1000 reactors with an increased level of pH. The values of cooling water leaks in turbine condensers the tube system of which is made of stainless steel or titanium alloy are given.

Supercompaction of radioactive waste at NPP Krsko

International Nuclear Information System (INIS)

Fink, K.; Sirola, P.

1996-01-01

The problem of radioactive waste management is both scientifically and technically complex and also deeply emotional issue. In the last twenty years the first two aspects have been mostly resolved up to the point of safe implementation. In the Republic of Slovenia, certain fundamentalist approaches in politics and the use of radioactive waste problem as a political tool, brought the final radioactive repository siting effort to a stop. Although small amounts of radioactive waste are produced in research institutes, hospitals and industry, major source of radioactive waste in Slovenia is the Nuclear Power Plant Krsko. When Krsko NPP was originally built, plans were made to construct a permanent radioactive waste disposal facility. This facility was supposed to be available to receive waste from the plant long before the on site storage facility was full. However, the permanent disposal facility is not yet available, and it became necessary to retain the wastes produced at the plant in the on-site storage facility for an extended period of time. Temporary radioactive storage capacity at the plant site has limited capacity and having no other options available NPP Krsko is undertaking major efforts to reduce waste volume generated to allow normal operation. This article describes the Radioactive Waste Compaction Campaign performed from November, 1994 through November, 1995 at Krsko NPP, to enhance the efficiency and safety of storage of radioactive waste. The campaign involved the retrieval, segmented gamma-spectrum measurement, dose rate measurement, compaction, re-packaging, and systematic storage of radioactive wastes which had been stored in the NPP radioactive waste storage building since plant commissioning. (author)

Perspectives of Living PSA in NPP Krsko

International Nuclear Information System (INIS)

Vrbanic, I.; Kastelan, M.

1996-01-01

Nuclear power plant Krsko has completed the Level 1/Level 2 Probabilistic Safety Analysis (PSA) for internal initiating events and is in the process of completing the same for the external initiators. The analysis completed up to now has provided a valuable insight into a plant risk profile. In NPP Krsko there is a plan to use the PSA model as a permanent tool for the risk based applications and incorporate it into a decision making process. In order to achieve this there is a need to permanently maintain the PSA model in a manner that it reflects both the plan configuration/design at a time point and the operational experience up to the time point. All the activities aimed toward keeping the PSA model up-to-dated in this sense are usually referred to as a Living PSA (LPSA) program. NPP Krsko is in the process of defining and proceduralizing a LPSA program that would be plant specific and based on known world practices. Further, in order to be suitable for risk based applications the PSA model must be flexible in a sense that modifications to the base case model may be done easily and requantifications performed quickly as to evaluate various conditions imposed by real or hypothetical situations. NPP Krsko PSA model has been based on licensing type software. The requirements specified above dictate the transfer of the overall model to an application oriented software of newer generation with larger capabilities. The transfer becomes a part of a mentioned ongoing effort aimed at establishing LPSA model and concept. The paper present this effort and the perspectives of LPSA concept and risk based applications in NPP Krsko. (author)

Tritium liquid effluents from the Krsko NPP

International Nuclear Information System (INIS)

Savli, S.; Krizman, M.; Nemec, T.; Cindro, M.; Stritar, A.; Vokal Nemec, B.; Janzekovic, H.

2007-01-01

In the past, 12-months' fuel cycles in the Krsko NPP had not caused any problems regarding compliance with its Technical Specifications and license limits on liquid tritium releases (20 TBq/year, 8 TBq/three months). The first 18-months' fuel cycle, which was introduced in 2004, required fuel with higher enrichment, higher boron concentration in the primary coolant and more fuel rods with burnable poisons. In 2005, the NPP operated without refueling outage for the whole year and produced the highest amount of energy so far. Due to these facts and a few unplanned shutdowns and power reductions, production of tritium and releases increased strongly in 2005. As a result, the Krsko NPP hardly succeeded to stay within regulatory limits on tritium releases. However, the three-months' limit was exceeded in the first quarter of 2006. On the basis of conclusions acquired from the SNSA's study and practice of other European countries the SNSA considerably increased the annual limit of permitted liquid tritium releases (from 20 TBq to 45 TBq) and abolished the three-months' limit. At the same time, the SNSA reduced the limit of fission and activation products by halves. (author)

Variations and trends of terrestrial NPP and its relation to climate

Indian Academy of Sciences (India)

Considering global climate change, near surface temperature is the major factor affecting the terrestrial ecosystem, followed by the precipitation. This means terrestrial ecosystem NPP is more closely related to near surface temperature than precipitation. Between 1976 and 2005, NPP shows an obvious increasing temporal ...

New Emergency control center of Slovenske Elektrarne Bohunice NPP

International Nuclear Information System (INIS)

Pecko, E.

2012-01-01

Emergency preparedness of nuclear power plant and operation assurance in case of a possible emergency calls to have devices for emergency response with equipment for rapid detection and continuous evaluation of anticipated events. Chief executive body designated to manage a nuclear power plant during major events is the emergency committee (EC). Emergency Committee is a part of the Emergency Response Organization (ERO). The following centers are on alert to ensure the activities of the ERO - Emergency Response office: - control room (CR) and emergency control room (ECR); - emergency management center (EMC); - Monitoring Centre (MC); - emergency backup control center (EBCC); - congregations of civil protection (CP) and CP shelters; - communications with warning and notification system (VARVYR). From a historical and practical point of view in the vicinity of Jaslovske Bohunice has been set up a joint emergency control center. The center was located on the territory of the former already inoperative V1 NPP. V1 NPP is currently integrated into the organizational structure of JAVYS. Operating Bohunice V2 NPP plant is a designated part of the Slovenske Elektrarne, a. s., whose majority owner is an Italian operator ENEL. In terms of various relevant factors, it was decided to build a new emergency management center on the territory of operating V2 NPP, meet the current standards.

Improvement of waste release control in French NPP

International Nuclear Information System (INIS)

Samson, T.; Lucquin, E.; Dupin, M.; Florence, D.; Grisot, M.

2002-01-01

The new waste release control in French NPP is more restrictive than the old one and needs heavy investment to bring plants to compliance with it. The great evolutions are a chemical follow up on more chemicals with a higher measurement frequency and with lower maximum concentrations and a specific measurement of carbon 14. Regarding radioactive releases, a new counting has been settled and activity of carbon 14 release is now measured and no longer calculated. The evolution of the French regulation leads to develop specific procedures and analytical techniques in chemistry and in radiochemistry (UV spectrometric methods, carbon 14 measurements,..) EDF NPP operators have launched a voluntarist process to reduce their releases since the beginning and before the evolution of the regulation. EDF priorities in terms of environment care lead henceforth to implement a global optimisation of the impact for a better control of releases. The new regulation will help EDF to reach its goals because it covers all the aspects in one administrative document: it is seen as a real simplification and a clarification towards public. In addition, this new regulation fits in with international practices which will allow an easier comparison of results between EDF and foreign NPP. These big environmental concerns lead EDF to create a national dedicated laboratory (LAMEN) in charge of developing specific measurement procedures to be implemented either by NPP or by sub-contractor laboratories. (authors)

Disposal of spent nuclear fuel from NPP Krsko

International Nuclear Information System (INIS)

Mele, I.

2004-01-01

In order to get a clear view of the future liabilities of Slovenia and Croatia regarding the long term management of radioactive waste and spent nuclear fuel produced by the NPP Krsko, an estimation of disposal cost for low and intermediate level waste (LILW) as well as for spent nuclear fuel is needed. This cost estimation represents the basis for defining the target value for the financial resources to be accrued by the two national decommissioning and waste disposal funds, as determined in the agreement between Slovenia and Croatia on the ownership and exploitation of the NPP Krsko from March 2003, and for specifying their financial strategies. The one and only record of the NPP Krsko spent fuel disposal costs was made in the NPP Krsko Decommissioning Plan from 1996 [1]. As a result of incomplete input data, the above SF disposal cost estimate does not incorporate all cost elements. A new cost estimation was required in the process of preparation of the Joint Decommissioning and Waste Management Programme according to the provisions of the above mentioned agreement between Slovenia and Croatia. The basic presumptions and reference scenario for the disposal of spent nuclear fuel on which the cost estimation is based, as well as the applied methodology and results of cost estimation, are presented in this paper. Alternatives to the reference scenario and open questions which need to be resolved before the relevant final decision is taken, are also briefly discussed. (author)

Improvement of waste release control in French NPP

Energy Technology Data Exchange (ETDEWEB)

Samson, T.; Lucquin, E.; Dupin, M. [EDF/GDL (France); Florence, D. [EDF/GENV (France); Grisot, M. [EDF/CNPE Saint Laurent (France)

2002-07-01

The new waste release control in French NPP is more restrictive than the old one and needs heavy investment to bring plants to compliance with it. The great evolutions are a chemical follow up on more chemicals with a higher measurement frequency and with lower maximum concentrations and a specific measurement of carbon 14. Regarding radioactive releases, a new counting has been settled and activity of carbon 14 release is now measured and no longer calculated. The evolution of the French regulation leads to develop specific procedures and analytical techniques in chemistry and in radiochemistry (UV spectrometric methods, carbon 14 measurements,..) EDF NPP operators have launched a voluntarist process to reduce their releases since the beginning and before the evolution of the regulation. EDF priorities in terms of environment care lead henceforth to implement a global optimisation of the impact for a better control of releases. The new regulation will help EDF to reach its goals because it covers all the aspects in one administrative document: it is seen as a real simplification and a clarification towards public. In addition, this new regulation fits in with international practices which will allow an easier comparison of results between EDF and foreign NPP. These big environmental concerns lead EDF to create a national dedicated laboratory (LAMEN) in charge of developing specific measurement procedures to be implemented either by NPP or by sub-contractor laboratories. (authors)

Standard protocol for evaluation of environmental transfer factors around NPP sites

International Nuclear Information System (INIS)

Hegde, A.G.; Verma, P.C.; Rao, D.D.

2009-01-01

This document presents the standard procedures for evaluation of site specific environmental transfer factors around NPP sites. The scope of this document is to provide standard protocol to be followed for evaluation of environmental transfer factors around NPP sites. The studies on transfer factors are being carried out at various NPP sites under DAE-BRNS projects for evaluation of site specific transfer factors for radionuclides released from power plants. This document contains a common methodology in terms of sampling, processing, measurements and analysis of elemental/radionuclides, while keeping the site specific requirements also in place. (author)

Core Knowledge Preservation and Transfer System Establishment and Utilization for NPP

International Nuclear Information System (INIS)

Kim, Bae-Joo; Kim, Gwang-Bong

2008-01-01

Knowledge is the most important factor in the safe and reliable operation of NPP. One generation has passed since we began to operate NPP in Korea. And then it became time to retire much experienced personnel in NPP. Although we have many kinds of knowledge sharing systems inside KHNP, we don't have any systematic experience knowledge preservation and transfer systems that are important for the operation of NPP. So we have lost important experience knowledge since we started operating. Especially, KHNP has adopted an internal promotion system as the human resource management policy, which induced frequent job position changes of staff members because there were job positions for a good promotion. Additionally, KHNP doesn't overlap jobs for long enough periods between previous staff and new staff when staff changes occur. With these reasons KHNP could not accumulate experience knowledge inside the company system. Therefore, KHNP could not preserve and transfer to the next generation the experience related to NPP operations systematically. To resolve these issues KNPEI performed a research project from March 2006 to September 2007. The purpose of this report is to introduce the experience knowledge preservation and transfer system that KNPEI has established and the utilization of the system

Factors influencing the renal arterial Doppler waveform: a simulation study using an electrical circuit model (secondary publication)

Energy Technology Data Exchange (ETDEWEB)

Sung, Chang Kyu [Dept. of Radiology, SMG-SNU Boramae Medical Center, Seoul National University College of Medicine, Seoul (Korea, Republic of); Han, Bong Soo [Dept. of Radiological Science, College of Health Science, Yonsei University, Wonju (Korea, Republic of); Kim, Seung Hyup [Dept. of Radiology, Institute of Radiation Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of)

2016-01-15

The goal of this study was to evaluate the effect of vascular compliance, resistance, and pulse rate on the resistive index (RI) by using an electrical circuit model to simulate renal blood flow. In order to analyze the renal arterial Doppler waveform, we modeled the renal blood-flow circuit with an equivalent simple electrical circuit containing resistance, inductance, and capacitance. The relationships among the impedance, resistance, and compliance of the circuit were derived from well-known equations, including Kirchhoff’s current law for alternating current circuits. Simulated velocity-time profiles for pulsatile flow were generated using Mathematica (Wolfram Research) and the influence of resistance, compliance, and pulse rate on waveforms and the RI was evaluated. Resistance and compliance were found to alter the waveforms independently. The impedance of the circuit increased with increasing proximal compliance, proximal resistance, and distal resistance. The impedance decreased with increasing distal compliance. The RI of the circuit decreased with increasing proximal compliance and resistance. The RI increased with increasing distal compliance and resistance. No positive correlation between impedance and the RI was found. Pulse rate was found to be an extrinsic factor that also influenced the RI. This simulation study using an electrical circuit model led to a better understanding of the renal arterial Doppler waveform and the RI, which may be useful for interpreting Doppler findings in various clinical settings.

Factors influencing the renal arterial Doppler waveform: a simulation study using an electrical circuit model (secondary publication)

International Nuclear Information System (INIS)

Sung, Chang Kyu; Han, Bong Soo; Kim, Seung Hyup

2016-01-01

The goal of this study was to evaluate the effect of vascular compliance, resistance, and pulse rate on the resistive index (RI) by using an electrical circuit model to simulate renal blood flow. In order to analyze the renal arterial Doppler waveform, we modeled the renal blood-flow circuit with an equivalent simple electrical circuit containing resistance, inductance, and capacitance. The relationships among the impedance, resistance, and compliance of the circuit were derived from well-known equations, including Kirchhoff’s current law for alternating current circuits. Simulated velocity-time profiles for pulsatile flow were generated using Mathematica (Wolfram Research) and the influence of resistance, compliance, and pulse rate on waveforms and the RI was evaluated. Resistance and compliance were found to alter the waveforms independently. The impedance of the circuit increased with increasing proximal compliance, proximal resistance, and distal resistance. The impedance decreased with increasing distal compliance. The RI of the circuit decreased with increasing proximal compliance and resistance. The RI increased with increasing distal compliance and resistance. No positive correlation between impedance and the RI was found. Pulse rate was found to be an extrinsic factor that also influenced the RI. This simulation study using an electrical circuit model led to a better understanding of the renal arterial Doppler waveform and the RI, which may be useful for interpreting Doppler findings in various clinical settings

Feature extraction and sensor selection for NPP initiating event identification

International Nuclear Information System (INIS)

Lin, Ting-Han; Wu, Shun-Chi; Chen, Kuang-You; Chou, Hwai-Pwu

2017-01-01

Highlights: • A two-stage feature extraction scheme for NPP initiating event identification. • With stBP, interrelations among the sensors can be retained for identification. • With dSFS, sensors that are crucial for identification can be efficiently selected. • Efficacy of the scheme is illustrated with data from the Maanshan NPP simulator. - Abstract: Initiating event identification is essential in managing nuclear power plant (NPP) severe accidents. In this paper, a novel two-stage feature extraction scheme that incorporates the proposed sensor type-wise block projection (stBP) and deflatable sequential forward selection (dSFS) is used to elicit the discriminant information in the data obtained from various NPP sensors to facilitate event identification. With the stBP, the primal features can be extracted without eliminating the interrelations among the sensors of the same type. The extracted features are then subjected to a further dimensionality reduction by selecting the sensors that are most relevant to the events under consideration. This selection is not easy, and a combinatorial optimization technique is normally required. With the dSFS, an optimal sensor set can be found with less computational load. Moreover, its sensor deflation stage allows sensors in the preselected set to be iteratively refined to avoid being trapped into a local optimum. Results from detailed experiments containing data of 12 event categories and a total of 112 events generated with a Taiwan’s Maanshan NPP simulator are presented to illustrate the efficacy of the proposed scheme.

Nuclear Oversight Function at Krsko NPP

International Nuclear Information System (INIS)

Bozin, B.; Kavsek, D.

2010-01-01

The nuclear oversight function is used at the Krsko NPP constructively to strengthen safety and improve performance. Nuclear safety is kept under constant examination through a variety of monitoring techniques and activities, some of which provide an independent review. The nuclear oversight function at the Krsko NPP is accomplished by Quality and Nuclear Oversight Division (SKV). SKV has completed its mission through a combination of compliance, performance and effectiveness-based assessments. The performance-based assessment is an assessment using various techniques (observations, interviews, walk-downs, document reviews) to assure compliance with standards and regulations, obtain insight into performance, performance trends and also to identify opportunities to improve effectiveness of implementation. Generally, the performance-based approach to oversight function is based on some essential elements. The most important one which is developed and implemented is an oversight program (procedure). The program focuses on techniques, activities and objectives commensurate with their significance to plant operational safety. These techniques and activities are: self-assessments, assessments, audits, performance indicators, monitoring of corrective action program (CAP), industry independent reviews (such as IAEA's OSART and WANO Peer Review), industry benchmarking etc. Graded approach is an inherent product of a performance based program and ranking process. It is important not only to focus on the highest ranked performance based attributes but to lead to effective utilization of an oversight program. The attributes selected for oversight need to be based on plant specific experience, current industry operating experience, supplier's performance and quality issues. Collaboration within the industry and effective utility oversight of processes and design activities are essential for achieving good plant performance. So the oversight program must integrate relevant

Study on the risk-informed regulation of NPP

International Nuclear Information System (INIS)

Wang Chaogui

2007-01-01

The risk-informed regulation is a modern type of NPP safety management mode using both deterministic and probabilistic approaches. It is necessary to entirely and systematically study the associated regulations, standards and practices in order to promote the developments of risk-informed regulations in China. This paper introduces the risk-informed regulation, gives out the basic principles, method and acceptance risk criteria of risk-informed decision,making, discusses the PSA requirements for risk-informed decision-making and makes some suggestions about the application of risk-informed regulations in Chinese NPP. (authors)

Methodology transfer for the preparation of NPP decommissioning for leading personnel of the Ignalina NPP and for the representatives of Lithuanian authorities

International Nuclear Information System (INIS)

Ackermann, L.; Baecker, A.

2004-01-01

At request of the Lithuanian government to receive support for the preparation of the decommissioning of Ignalina NPP, a bilateral project was financed by the German federal government to transfer experience from the decommissioning of the Greifswald and Rheinsberg NPPs to the management staff of the Ignalina NPP and to the representatives of the Lithuanian authorities in charge of the decommissioning. The methodology transfer project was prepared and carried out under the leadership of the Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) mbH. The practical implementation was within the responsibility of Energiewerke Nord GmbH (EWN) in cooperation with other German subcontractors. The methodology transfer comprised the task fields of project management, project planning, licensing procedure and waste management as well as social aspects of the further development of the industrial site. Five intensive one-week seminars were conducted mainly at the Greifswald NPP site and the knowledge gained was then consolidated in two evaluation seminars at the Ignalina NPP. As the basis for the training realised in 2002 and 2003, EWN provided about 2000 power-point illustrations, more than 200 transparencies and four video films. The training handouts produced by EWN were delivered to the seminar participants in Russian and English language and documented in the database ''Technische Dokumentation Ost'' (DOKU OST) of GRS. (orig.)

NPP Krsko full scope simulator verification and qualification

International Nuclear Information System (INIS)

Krajnc, B.; Glaser, B.; Novsak, M.; Spiler, J.

1998-01-01

NPP Krsko (NEK) will, as a part of the Modernization plan, obtain also Krsko Full Scope Simulator (KFSS). Contract has been awarded to CAE Electronics for the design, construction and integration. KFSS will support in real time, the training for the complete range of operation, which can be performed from the main control room and some selected plant areas (remote shutdown panels, etc). Based on the lessons learned on development of NPP Krsko Basic Principle Simulator we decided for active approach. That means that NPP Krsko personnel will be heavily involved into all phases of KFSS development and testing. Since NPP Krsko is going to replace the existing steam generators, raise the nominal power and perform necessary modifications to support the power uprate, it was decided that the development of the KFSS will be conducted in two steps: 1. Development of the models as well as all the hardware interface in the MCR for the existing plant Cycle 15 and then, 2. Models and hardware will be modified, added or replaced as needed to take into account the steam generator replacement and plant uprate projects. In spite of the fact that the simulator will be used for the training of the plant operators for the uprated conditions and with new steam generators, the upper described approach was selected since we want to be sure that the models will at the beginning adequately simulate the existing plant. For the existing conditions we have available reference data for different plant conditions, as well as data for different plant transients. By verifying that simulator will be able adequately simulate the existing conditions the level of confidence for the uprated simulator will be much higher. This is of special importance since it will support initial training for modernized plant conditions. In this paper the plan for verification and qualification of KFSS as well as the amount of the work needed on NPP Krsko side to develop the test acceptance criteria will be presented.(author)

Selection of index complex for the NPP operator activity efficiency

Energy Technology Data Exchange (ETDEWEB)

Kolesnik, A I; Chertorizhskij, E A

1984-01-01

Preconditions for choice of NPP operator activity efficiency index are determined. Results of the choice are given and a method for determination of generalized and particular parameters by means of which NPP operator activity efficiency can be estimated is considered. An algorithm of diagnosis of reason for unsuccess of operator activity based on assessment of psychological factors of complicacy is suggested.

Joint probability safety assessment for NPP defense infrastructure against extreme external natural hazards

International Nuclear Information System (INIS)

Guilin, L.; Defu, L.; Huajun, L.; Fengqing, W.; Tao, Z.

2012-01-01

With the increasing tendency of natural hazards, the typhoon, hurricane and tropical Cyclone induced surge, wave, precipitation, flood and wind as extreme external loads menacing Nuclear Power Plants (NPP) in coastal and inland provinces of China. For all of planned, designed And constructed NPP the National Nuclear Safety Administration of China and IAEA recommended Probable Maximum Hurricane /Typhoon/(PMH/T), Probable Maximum Storm Surge (PMSS), Probable Maximum Flood (PMF), Design Basis Flood (DBF) as safety regulations for NPP defense infrastructures. This paper discusses the joint probability analysis of simultaneous occurrence typhoon induced extreme external hazards and compare with IAEA 2006-2009 recommended safety regulation design criteria for some NPP defense infrastructures along China coast. (authors)

Safety enhancement concept for NPP of new generation with VVER reactors

International Nuclear Information System (INIS)

Bezlepkin, V.; Kukhtevich, I.; Semashko, S.; Svetlov, S.; Solodovnikov, A.

2004-01-01

With the present day conditions, in order to successfully promote new NPP designs in the electric power markets, it is necessary to ensure enhanced technical/economic performances provided that international safety requirements are properly adhered to. When compared with high-powered nuclear power plants, NPP VVER-640 design (medium powered) possesses a number of advantages for the regions with undeveloped energy systems. Reduced specific energy intensity of the core adopted in this type of reactor allows to ensure the emergency cooldown of the reactor plant by passive means and to minimize the 'human factor' risk and external effects and provide sound substantiations as to how to retain corium inside RPV in case of severe accidents. At the same time, high-powered NPPs seem to be promising for regions with developed energy systems. Among such designs, NPP VVER-1000 and VVER-1500 designs are the most desirable. Configuration of new generation NPP with VVER-1500 is to be selected based on the gained experience in designing NPPs of previous generations considering the latest safety requirements and situation in the domestic and global energy markets for the time being and in the short run. Recent IAEA publications and latest EUR requirements insist that the following key safety indices should be established for new NPP designs: - aggregated frequency of core melting is 10 -6 (1/year); - frequency of maximum accident release is 10 -7 (1/year). To meet the aforementioned criteria, it is necessary to implement some safety assurance principles recommended by IAEA (in-depth defence, single failure, redundancy, diversity, etc.), application of deterministic and probabilistic methods for selection of safety assurance activities and means and use of reasonable combination of active and passive systems. Application of VVER-640 concept to high-powered NPPs seems to be a formidable task due to a number of reasons, namely, it is quite difficult to carry out cooldown process

Tritium monitoring at NPP and enviromental area under survey

International Nuclear Information System (INIS)

Nurislamov, I.R.; Kham'yanov, L.P.; Panichkin, V.F.

1983-01-01

Methods and devices for tritium monitoring at NPP with the WWER-type reactors and the environment are described. Aqueous solutions of inorganic and organic compounds, water vapours in the air of NPP rooms and the environment atmosphere, free and bound water in soils and vegetation were the objects for monitoring. Methods of tritium sampling from the atmosphere as well as determination of its content in samples are presented. Special attention is paid to sample enrichment with tritium

NPP Temelin safety analysis reports and PSA status

International Nuclear Information System (INIS)

Mlady, O.

1999-01-01

To enhance the safety level of Temelin NPP, recommendations of the international reviews were implemented into the design as well as into organization of the plant construction and preparation for operation. The safety assessment of these design changes has been integrated and reflected in the Safety Analysis Reports, which follow the internationally accepted guidelines. All safety analyses within Safety Analysis Reports were repeated carefully considering technical improvements and replacements to complement preliminary safety documentation. These analyses were performed by advanced western computer codes to the depth and in the structure required by western standards. The Temelin NPP followed a systematic approach in the functional design of the Reactor Protection System and related safety analyses. Modifications of reactor protection system increase defense in depth and facilitate demonstrating that LOCA and radiological limits are met for non-LOCA events. The rigorous safety analysis methodology provides assurance that LOCA and radiological limits are met. Established and accepted safety analysis methodology and accepted criteria were applied to Temelin NPP meeting US NRC and Czech Republic requirements. IAEA guidelines and recommendations

Low level radioactive waste disposal in Kozloduy NPP in Bulgaria

International Nuclear Information System (INIS)

Stanchev, V.

2001-01-01

Kozloduy NPP is the biggest power plant in the Republic of Bulgaria. It is in operation since 1974 and for the past 25 years it has generated over 263 billion kWh electric power. The NPP share in the total electric production in 1998 was about 50%. It has six units in operation - four WWER 440 B-230 and two WWER 1000 B-320. In the nuclear reactor operation the generation of radioactive waste (RAW) is an inevitable process. The waste must be conditioned, stored and disposed of in a safe manner. There are no national radioactive waste disposal facilities, for waste generated by an NPP, in Bulgaria to the moment. This situation necessitates the storage of operational RAW to be carried out on site for a long period of time (30 to 50 years). Following the principle for protection of human health and environment now and in the future, Kozloduy NPP adopted the concept for conditioning the RAW to a stable solid form and placing the waste in a package which should keep its features for a sufficiently long term so that the package can be safely transported to the disposal site. (author)

An Analysis of Cyber-Attack on NPP Considering Physical Impact

Energy Technology Data Exchange (ETDEWEB)

Lee, In Hyo; Kang, Hyun Gook [KAIST, Daejeon (Korea, Republic of); Son, Han Seong [Joonbu University, Geumsan (Korea, Republic of)

2016-05-15

Some research teams performed related works on cyber-physical system which is a system that cyber-attack can lead to serious consequences including product loss, damage, injury and death when it is attacked. They investigated the physical impact on cyber-physical system due to the cyber-attack. But it is hard to find the research about NPP cyber security considering the physical impact or safety. In this paper, to investigate the relationship between physical impact and cyber-attack, level 1 PSA results are utilized in chapter 2 and cyber-attack analysis is performed in chapter 3. The cyber security issue on NPP is inevitable issue. Unlike general cyber security, cyber-physical system like NPP can induce serious consequences such as core damage by cyber-attack. So in this paper, to find how hacker can attack the NPP, (1) PSA results were utilized to find the relationship between physical system and cyber-attack and (2) vulnerabilities on digital control systems were investigated to find how hacker can implement the possible attack. It is expected that these steps are utilized when establishing penetration test plans or cyber security drill plans.

Survey of public participation potential regarding the Muria NPP program

International Nuclear Information System (INIS)

Yarianto-SBS; Sri Hariani Syarif; Heni Susiati; Imam Hamzah; Fepriadi

2003-01-01

Socio-culture aspect is a part of site feasibility evaluation of Nuclear Power Plant (NPP)program. Indonesia is under going democratization, therefore the paradigm of development has also been changed where the people have freedom or liberty and they can express their opinion independently. The people are significant factor that involving in the decision making of regional development.Even the socio-culture, such as social riot can reject the site. Therefore socio-culture aspect should be considered in the NPP site evaluation. The first step of the study,mapping of public participation potential should be conducted by field survey. The method used in there search is quantitative approach with field survey guided by questioner without any treatment of object sampled. Qualitative approach was also conducted by in-depth interview technique to collect more detailed information. Information were collected from general public without any stratification in the 10 km radius from NPP site. Sampling method used was full random sampling technique. The results of survey show that the most of the people have significant potential for participating in the NPP Program. Conducive atmosphere should be maintained by social setting, therefore the present good momentum will not be lost. (author)

An Analysis of Cyber-Attack on NPP Considering Physical Impact

International Nuclear Information System (INIS)

Lee, In Hyo; Kang, Hyun Gook; Son, Han Seong

2016-01-01

Some research teams performed related works on cyber-physical system which is a system that cyber-attack can lead to serious consequences including product loss, damage, injury and death when it is attacked. They investigated the physical impact on cyber-physical system due to the cyber-attack. But it is hard to find the research about NPP cyber security considering the physical impact or safety. In this paper, to investigate the relationship between physical impact and cyber-attack, level 1 PSA results are utilized in chapter 2 and cyber-attack analysis is performed in chapter 3. The cyber security issue on NPP is inevitable issue. Unlike general cyber security, cyber-physical system like NPP can induce serious consequences such as core damage by cyber-attack. So in this paper, to find how hacker can attack the NPP, (1) PSA results were utilized to find the relationship between physical system and cyber-attack and (2) vulnerabilities on digital control systems were investigated to find how hacker can implement the possible attack. It is expected that these steps are utilized when establishing penetration test plans or cyber security drill plans

Implementation of the II. Stage decommissioning of A1 NPP

International Nuclear Information System (INIS)

Ficher, T.

2015-01-01

Presentation is focused on the implementation of the II. stage decommissioning of A1 NPP. Introductory part focuses on brief characteristics of the power plant with a history of operation, basic technical parameters and actions that were made after operation. The next section describes the basic schedule for decommissioning, structure of management and implementation of the II. stage decommissioning of the A1 NPP and objectives of the individual stages. The last and largest part of the presentation is devoted to detailed description of the II. stage decommissioning of the A1 NPP, its individual tasks and verbal and visual description of the activities that were performed. Presented is decommissioning of the technology and construction of external objects NPP A1 including storage tanks for liquid RAW, next are presented activities carried out in the Main Production Unit - decommissioning of non-operating technologies in various places/rooms, management of waste arising from these activities, treatment of case of A1 long-term spent fuel storage and long-term spent fuel storage. The subsequent section is devoted to the management and handling of contaminated soil, concrete and construction waste, including management of VLLW. (authors)

Planning and management support for NPP personnel SAT-based training programmes. IAEA regional workshop. Working material

International Nuclear Information System (INIS)

1998-01-01

Within the European regional TC Project a workshop on Planning and Management Support for NPP Personnel SAT Based Training programmes was held at the Paks NPP Maintenance Training Centre in June 1998. It was organized jointly by IAEA and the Paks NPP. The objective of the workshop was to present the important experience gained by successful implementation of the IAEA Model Project on Strengthening Training for Safe Operation at Paks NPP as well as international experience in developing and carrying out the projects to upgrade NPP personnel training in particular maintenance training, and competence based Systematic Approach to Training (SAT). Twenty five participants from Armenia, Bulgaria, China, Czech republic, Hungary, Romania, Russia, Slovak Republic and Ukraine attended the workshop presenting and exchanging experiences in implementing NPP SAT-based training programmes

Assessment of NPP safety taking into account seismic and engineering-geological factors

International Nuclear Information System (INIS)

Yakovlev, E.A.

1990-01-01

Consideration is given to the problem of probabilistic analysis of NPP safety with account of risk of destructive effect of earthquakes and the danger of accidental geological processes (diapirism, karst etc.) under NPP operation. It is shown that account of seismic and engineering-geological (engineering-seismological) risk factors in probabilistic analysis of safety enables to perform anticipatory analysis of behaviour of principle plant objects and to improve safety of their operation by revealing the most unstable elements of geotechnical system forming the main contribution to the total NPP risk

Cernavoda NPP impact study on terrestrial and aquatic biota. Preliminary results

International Nuclear Information System (INIS)

Bobric, Elena; Bucur, Cristina; Popescu, Ion; Simionov, Vasile; Titescu, Gheorghe; Varlam, Carmen

2010-01-01

Recently, the awareness of the vulnerability of the environment has increased and the need to protect it against industrial pollutants has been recognized. The concept of sustainable development, requires new and developing international policies for environmental protection. See 'Protection of the environment from the effects of ionizing radiation' IAEA-TECDOC-1091, International Atomic Energy Agency, Vienna. As it is recommended in 'Cernavoda Unit No. 2 NPP Environmental Impact Assessment CES-03702-IAD-006', it is Cernavoda NPP responsibility to conduct an Ecological Risk Assessment study, mainly to assess the impact of nuclear power plant operation on terrestrial and aquatic biota. Long records from normal operation of Cernavoda Unit 1, wind pattern, meteorological conditions, and source terms data were used to evaluate areas of interest for environmental impact, conducting to a circle of 20 km radius around mentioned nuclear objective. The screening campaign established tritium level (because Cernavoda NPP is a CANDU type reactor, and tritium is the most important radioisotope evacuated in the environment) in air, water, soil and vegetation, focusing the interest area on particular ecosystem. Using these primary data it was evaluated which are the monitored ecological receptors and which are the measurement endpoints.This paper presents the Ecological Risk Assessment at Cernavoda NPP technical requirements, and the preliminary results of evaluating criteria for representative ecosystem components at Cernavoda NPP. (authors)

Regulatory review of NPP Krsko Periodic Safety Review

International Nuclear Information System (INIS)

Lovincic, D.; Muehleisen, A.; Persic, A.

2004-01-01

At the request of the Slovenian Nuclear Safety Administration (SNSA), Krsko NPP prepared a Periodic Safety Review (PSR) program in January 2001. This is the first PSR of NPP Krsko, the only nuclear power plant in Slovenia. The program was reviewed by the IAEA mission in May 2001 and approved by SNSA in July 2001. The program is made in accordance with the IAEA Safety Guide 'Periodic Safety Review of Operational Nuclear Power Plants' No. 50-SG-012 and with European practice. It contains a systematic review of operation of the NPP Krsko, including the review of the changes as a result of the modernization of the facility. The main tasks of PSR are review of plant status for each safety factor, development of aging and life cycle management program, review of seismic design and PSHA analysis and update of regulatory compliance program. The prioritization process of findings and action plan are also important tasks of PSR. The basic safety factors of the PSR review are: Operational Experience, Safety Assessment and Analyses, Equipment Qualification and Ageing Management, Safety Culture, Emergency Planing, Environmental Impact and Radioactive Waste, Compliance with license requirements and Prioritization. It had been agreed that SNSA will have reviewed all PSR reports generated during the PSR process. At the end of 2003 the PSR Summary Report with selected recommendations for action plan was completed and delivered to SNSA for review. The paper presents regulatory review of NPP Krsko PSR with emphasis on the evaluation of the PSR issues ranking process. (author)

Nonlinear modal analysis in NPP dynamics: a proposal

International Nuclear Information System (INIS)

Suarez Antola, R.

2005-07-01

We propose and briefly suggest how to apply the analytical tools of nonlinear modal analysis (NMA) to problems of nuclear reactor kinetics, NPP dynamics, and NPP instrumentation and control. The proposed method is closely related with recent approaches by modal analysis using the reactivity matrix with feedbacks to couple neutron kinetics with thermal hydraulics in the reactors core. A nonlinear system of ordinary differential equations for mode amplitudes is obtained, projecting the dynamic equations of a model of NPP onto the eigenfunctions of a suitable adjoint operator. A steady state solution of the equations is taken as a reference, and the behaviour of transient solutions in some neighbourhood of the steady state solution is studied by an extension of Liapunov's First Method that enables to cope directly with the non-linear terms in the dynamics. In NPP dynamics these differential equations for the mode amplitudes are of polynomial type of low degree A few dominant modes can usually be identified. These mode amplitudes evolve almost independently of the other modes, more slowly and tending to slave the other mode amplitudes. Using asymptotic methods, it is possible to calculate a closed form analytical approximation to the response to finite amplitude perturbations from the given steady spatial pattern (the origin of the space of mode amplitudes).When there is finite amplitude instability, the method allows us to calculate the threshold amplitude as a well defined function of system's parameters. This is a most significant accomplishment that the other methods cannot afford

The main trends of work on lifetime management of NPP

International Nuclear Information System (INIS)

Dragunov, Yu.; Kurakov, Yu.

1995-01-01

The major trends of works on NPP lifetime management are discussed: Co-ordinating and organizational activities; studying the degradation processes and residual life; elaboration and implementation of the measures to maintain/enhance safety level of NPPs operating within design life; development of control principals of advanced NPPs aging and safe life; creation and development of regulations in the field of NPP aging and life management. 7 figs

Balancing preventive and corrective maintenance in Cernavoda Unit 1 NPP

International Nuclear Information System (INIS)

Riedel, M.; Marinescu, S.

2000-01-01

The paper presents a short reminder of Romania's Cernavoda NPP entering commercial operation and a brief description of the CANDU-6 project on which Unit 1 is based. The short term objectives of the maintenance management, the status of the existing maintenance programmes as well as future predictable maintenance programmes are outlined together with the Government plan to complete the balance of NPP. (author)

Monitoring of Persons at the Exit from Bohunice NPP

International Nuclear Information System (INIS)

Kaizer, J.; Svitek, J.

2001-01-01

Full text: IAEA defines the principal requirement 'defence in depth' as a multilayer system in its authorised document - International Basic Safety Standards for Protection against Ionising Radiation, Safety Series No. 115. The principle of the multilayer system is: a failure at one zone is compensated or corrected at subsequent zones. The main argument why Bohunice NPP modernised its monitoring system at the exit from NPP was the implementation of the principle 'defence in depth'. Several instruments PM7 (Eberline) equipped with the plastic scintillation detectors had been bought because of the modernisation. The instruments had to be integrated into overall security system NPP without any restriction to the number of passing people. The supplier had to modify the basic instrument operation. NPP required a 'dynamic' monitoring version, this means the operation without stopping of a person within the instrument. After the modification the value of the RDA (Reliable Detectable Activity) of the instruments PM7 was within the interval 9.25-10.4 kBq for 137 Cs (dotted source in the middle of the instrument). RDA for the mix of activation products was 2-3 times lower. In conclusion of our paper the results of the monitoring are presented within tree years as well as a discussion about these results. Maximum values of contaminations measured were very low (several kBq) that represented very low risk from potential exposure. (author)

Environmental impact assessment of NPP decommissioning

International Nuclear Information System (INIS)

Hinca, R.

2009-01-01

In this presentation the following potential impacts of decommissioning of NPP are discussed: - Impacts on population; Impacts on natural environment; Land impacts; Impacts on urban complex and land utilisation; Possible impacts on area as a result of failure.

Studies of Effect Analysis of Electromagnetic Pulses (EMP) in Operating Nuclear Power Plants (NPP)

Energy Technology Data Exchange (ETDEWEB)

Ye, Song Hae; Ryu, Ho Sun; Kim, Min Yi; Lee, Eui Jong [KHNP, Daejeon (Korea, Republic of)

2016-05-15

The effect analysis of electromagnetic pulses (EMPs) has been studied for the past year by the Central Research Institute of Korea Hydro Nuclear Power Co. (KHNP) in order to better establish safety measures in operating nuclear power plants. What is an electromagnetic pulse (EMP)? As a general term for high-power electromagnetic radiation, it refers to strong electromagnetic pulses that destroy only electronic equipment devices in a short period without loss of life. The effect analysis of EMPs in operating NPPs and their corresponding safety measures in terms of selecting target devices against EMP impact have been examined in this paper. In general, domestic nuclear power plants do apply the design of fail-safe concepts. For example, if key instruments of a system fail because of EMPs, the control rods of a nuclear reactor are dropped automatically in order to maintain safe conditions of the NPP. Reactor cooling presents no problem because the diesel generator will adopt the analog starting circuit least affected by the electromagnetic waves.

LTO License Application Project NPP Borssele

International Nuclear Information System (INIS)

Jong, A.E. de; Blom, F.J.; Leilich, J.

2012-01-01

Borssele NPP plans to extend its operating life with 20 years until 2034. Borssele has started the project LTO 'bewijsvoering' (LTO 'Justification') in order to meet the requirements of the Dutch regulator. The outline of the project is based on IAEA safety guide 57 'Safe Long Term Operation of Nuclear Power Plants'. This paper describes the contents and coherence of the different parts in the project and how these respond to the IAEA guidelines on LTO. The goal of the project LTO 'bewijsvoering' is to ensure that safety and safety relevant systems, structures and components continue to perform their intended functions during long term operation. The outcome of the project LTO 'bewijsvoering' will be used for a license change application and this will be submitted to the Dutch regulator KFD for approval of prolonged operation of Borssele NPP after 2013. (author)

Radiological characterization of the main circulation circuit of the 1st unit at Ignalina NPP

International Nuclear Information System (INIS)

Poskas, P.; Zujus, R.; Brazauskaite, A. and others

2003-01-01

A preliminary assessment of the main circulation circuit (MCC) equipment contamination at the reactor final shut-down and analysis of the contamination variation with time are presented. In order to perform this assessment, data on MCC element characteristics, the coolant characteristics, the system operational conditions, etc. were collected. The modified computer code LLWAA-DECOM (Belgium) was used to determine contamination of the system elements. As a result, nuclide vectors and surface dose rates of deposits for every MCC element were determined. The modeling results were compared to the measurement results of the dose rates. (author)

Structure study and design of Qinshan NPP PCCV

International Nuclear Information System (INIS)

Xia Zufeng; Xu Yongzhi; Wang Tianzhen; Wu Jibiao

1993-02-01

The design process of Qinshan NPP (nuclear power plant) PCCV (prestressed concrete containment vessel) is summarized. The tendon test, structural description, design bases and analysis method are introduced. The arrangement for preventing concrete from cracking and design features of post-tensioning system and steel liner are presented. The results of model test and non-linear analysis for ultimate load in Qinshan NPP PCCV are also given. Through the integrity test of PCCV, it shows that the test values are in agreement with predicted values, the structure is excellent and the performance of leak tightness conforms to the safety requirements

Corrosion strength monitoring of NPP component residual lifetime

International Nuclear Information System (INIS)

Denisov, V.G.; Belous, V.N.; Arzhaev, A.I.; Shuvalov, V.A.

1994-01-01

Importance of corrosion and fatigue monitoring; types of corrosion determine the NPP equipment life; why automated on-line corrosion and fatigue monitoring is preferable; major stages of lifetime monitoring system development; major groups of sensors for corrosion and strength monitoring system; high temperature on-line monitoring of water chemistry and corrosion; the RBMK-1000 NPP unit automatic water chemistry and corrosion monitoring scheme; examples of pitting, crevice and general corrosion forecast calculations on the basis of corrosion monitoring data; scheme of an experimental facility for water chemistry and corrosion monitoring sensor testing. 2 figs., 4 tabs

NPP life management program - status report for Slovenia

International Nuclear Information System (INIS)

Glumac, B.

1998-01-01

Status report on NPP life management in Slovenia is dealing with possible life extension of NPP Krsko which comprises: replacement of steam generator; power upgrade; exchange of plant process computer; snubber reduction program, additional forced ventilation cooling system. Fuel improvements are predicted as well as the problems of storing spent fuel, low and intermediate waste if the plant is to operate through 2023 and possibly beyond that date. Related research activities are concerned with radiation damage, modelling of reactor core parameters by Monte Carlo calculations and PSA and severe accidents studies. Most of the activities are performed in cooperation with foreign organisations

The main conditions ensured problemless implementation of 235U high enriched fuel in Kozloduy NPP (Bulgaria) - WWER-1000 Units

International Nuclear Information System (INIS)

Dobrevski, I.; Zaharieva, N.; Minkova, K.; Michaylov, G.; Penev, P.; Gerchev, N.

2009-01-01

The collected water chemistry and radiochemistry data during the operation of the Kozloduy NPP Unit 5 for the period 2006-2009 (12-th, 13-th 14-th and 15-th fuel cycles) undoubtedly indicate for WWER-1000 Units (whose specific features are: Steam generators with austenitic stainless steel 08Cr18N10T tubing; Steam generators are with horizontal straight tubing and Fuel elements cladding material is Zr-1%Nb (Zr1Nb) alloy), that one realistic way for problemless implementation of 235 U high enriched fuel have been found. The main feature characteristics of this way are: Implementation of solid neutron burnable absorbers together with the dissolved in coolant neutron absorber - natural boric acid; Application of fuel cladding materials with enough corrosion resistance by the specific fuel cladding environment created by presence of SNB; Keeping of suitable coolant water chemistry which ensures low corrosion rates of core- and out-of-core- materials and limits in core (cladding) depositions and restricts out-of-core radioactivity buildup. The realization of this way in WWER-1000 Units in Kozloduy NPP was practically carried out through: 1) Implementation of Russian fuel assemblies TVSA which have as fuel cladding material E-110 alloy (Zr1Nb) with enough high corrosion resistance by presence of sub-cooled nucleate boiling (SNB) and use burnable absorber (Gd) integrated in the uranium-gadolinium (U-Gd 2 O 3 ) fuel (fuel rod with 5.0% Gd 2 O 3 ); 2) Development and implementation of water chemistry primary circuit guidelines, which require the relation between boric acid concentration and total alkalising agent concentrations to ensure coolant pH 300 = 7.0 - 7.2 values during the whole operation period. The above mentioned conditions by the passing of WWER-1000 Units in NPP Kozloduy to uranium fuel with 4.4% 235 U (TVSA fuel assemblies) practically ensured avoidance of the creation of the necessary conditions for AOA onset. The operational experience (2006-2009) of the

Dukovany NPP operation

International Nuclear Information System (INIS)

Vlcek, Jaroslav

2010-01-01

The topics discussed include: Dukovany NPP among CEZ Group power plants; International missions at the plant; Plant operation results; and Strategic goals and challenges. Historical data are presented in the graphical form, such as the unit capacity factor, unplanned capability loss factor, unplanned automatic scrams, fuel reliability, industrial safety accident rate, collective radiation exposure, WANO index, power generation data, and maximum achievable power by the end of year. Also discussed were the company culture and human resources, maintenance, power uprate, and related phenomena. (P.A.)

Studying the sampling representativeness in the NPP ventilation ducts

International Nuclear Information System (INIS)

Sosnovskij, R.I.; Fedchenko, T.K.; Minin, S.A.

2000-01-01

Measurements of the gas and aerosol voluminous activity in the NPP ventilation ducts are an important source of information on the radiation contaminants ingress into the environmental medium. These measurements include sampling, samples transport and proper measurements. The work is devoted to calculation of metrological characteristics of the sampling systems for the NPP gas-aerosol releases by different parameters of these systems and ventilation ducts. The results obtained are intended for application by designing such systems and their metrological certification [ru

EOPs at NPP Temelin: Analytical support for EOPs verification

International Nuclear Information System (INIS)

Bica, M.

1999-01-01

The process of implementation of symptom-based emergency operating procedures (EOPs) started at the NPP Temelin in 1993. The process has the following phases: development of symptom-based EOPs; EOPs verification; EOPs validation; operating personnel training; EOPs control and experience feedback. The development of Temelin specific EOPs was based on technology and know-how transfer using the Emergency Response Guidelines Methodology developed by the Westinghouse Owner Group. In this lecture the implementation of symptom-based EOPs in the the NPP Temelin is described

Solution of multiple circuits of steam cycle HTR system

International Nuclear Information System (INIS)

Li, Fu; Wang, Dengying; Hao, Chen; Zheng, Yanhua

2014-01-01

In order to analyze the dynamic operation performance and safety characteristics of the steam cycle high temperature gas cooled reactor (HTR) systems, it is necessary to find the solution of the whole HTR systems with all coupled circuits, including the primary circuit, the secondary circuit, and the residual heat removal system (RHRS). Considering that those circuits have their own individual fluidity and characteristics, some existing code packages for independent circuits themselves have been developed, for example THEMRIX and TINTE code for the primary circuit of the pebble bed reactor, BLAST for once through steam generator. To solve the coupled steam cycle HTR systems, a feasible way is to develop coupling method to integrate these independent code packages. This paper presents several coupling methods, e.g. the equivalent component method between the primary circuit and steam generator which reflect the close coupling relationship, the overlapping domain decomposition method between the primary circuit and the passive RHRS which reflects the loose coupling relationship. Through this way, the whole steam cycle HTR system with multiple circuits can be easily and efficiently solved by integration of several existing code packages. Based on this methodology, a code package TINTE–BLAST–RHRS was developed. Using this code package, some operation performance of HTR–PM was analyzed, such as the start-up process of the plant, and the depressurized loss of forced cooling accident when different number of residual heat removal trains is operated

The changing of land use and land management in Ignalina NPP region

International Nuclear Information System (INIS)

Milius, J.; Ribokas, G.

1998-01-01

The investigated locality (Ignalina NPP) represents territory of NPP and Visaginas town as well as agrarian territories of three former environs Dukshtas and Rimshe (Ignalina district) and Turmantas (Zarasai district). The changes of land, started with the beginning of construction works of NPP (1974) and are still taking place, are analyzed. The data on the land fund and current data of land reform agrarian services were used. The changes of the plots of farming lands in agrarian territories were preconditioned by the same factors which operated in other territories of hilly agrarian landscape. In the drained terrains the plots of farming lands increased, whereas, in other territories re naturalization processes set in resulting in the increase of the areas covered with forests and bushes which were not used for agricultural purposes. Thus, we may assert that the impact of the NPP itself on the change of the structure of farming lands in agrarian territories was minimal. It manifested not as a permanent process but as a spontaneous fact - a mechanical allotment of a plots of land for building the NPP and town itself. The comparison of the structure of farming lands at the moment of allotment with the data of 1995 revealed that during the mentioned period the farming land were completely destroyed (1003 ha of ploughed lands, 168 ha - grasslands, 180 ha - pastures). The forest area was reduced by 625 ha. The destroyed farming lands were occupied by territories under buildings (719 ha), artificial ground cover (159 ha), and high tension current lines (over 800 ha) which are absolutely unfit neither for agriculture nor forestry. Though the NPP and Visaginas town exerted no appreciable influence on the structure of farming lands in the surrounding territories they substantially changed the territory of NPP and Visaginas. The former wooded - agrarian landscape was replaced by an untypical for these places technical - urbanized landscape. This should be taken into

The EC TACIS project 'Social impact of closing Chornobyl NPP' objectives, tasks and intended outcomes

International Nuclear Information System (INIS)

Schoen, A.

2001-01-01

Being part of the common activities of Slavutich and ChNPP, our EC TACIS project representatives already actively participated in the elaboration of the state programme aimed to ensure the social security of the ChNPP personnel and the population of Slavutich in the result of the final shut down of ChNPP

Polish media and public opinion on NPP Mochovce commissioning

International Nuclear Information System (INIS)

Latek, Stanislaw

1999-01-01

The so called 'Mochovce Problem' was one of the major topics in Polish media in the period from May to July 1998. The nuclear power plant commissioning caused an unexpectedly strong reaction, especially in the newspapers, slightly less so in electronic media. Faced with clearly hostile media reaction to Mochovce NPP, the National Atomic Energy Agency representatives, together with atomic and nuclear experts, undertook to change these attitudes. In numerous interviews, letters to the editors and talks with journalists, they attempted to correct the mistakes, explain the true safety situation in the nuclear power plant, by whom it was constructed, who supervised and tested the systems and so on. The completion of Mochovce NPP construction improved significantly the electricity balance in Slovakia, thus decreasing the pressure for continuing the operation of older Bohunice V1 units beyond their design lifetime. For this reason, as well as in view of striving for improvement in environmental factors beyond Polish southern border, especially after Kyoto/97 decisions on greenhouse gases emissions, the public opinion in Poland should support the Mochovce NPP construction. In 1996 Poland has signed with Slovakia a bilateral inter-governmental agreement on the prompt notification on nuclear accidents and on the cooperation in the nuclear safety and radiological protection matters. On the basis of this agreement the experts from Polish National Atomic Energy Agency are in perpetual contact with Slovakian Nuclear Regulatory Body and in each and every moment can obtain full and comprehensive information on the plant parameters iportant for nuclear safety. The experts explanations, together with the NAEA top management visit to the plant itself, brought some results. The media became less aggressive, and Polish public and authorities - contrary to the Austrians - do not protest loudly against the commissioning of this newest European NPP. Now, in December 1998, the tune of

Distinct characteristics of NPP HRD and establishment of KINGS in Korea

International Nuclear Information System (INIS)

Namgung, Ihn

2013-01-01

Full text:Korean government set-up nuclear energy department within the ministry of education in 1956 and joined IAEA in 1957 and set up nuclear energy agency in 1959, and installed the first research reactor in 1962. The Korean Government started constructing NPP in 1971 that had started commercial operation in 1978. The first oil shock in 1973 had devastated Korean economy and that made Korean Government to accelerate the construction of NPPs. Since then Korea steadily constructed NPP as well as invested in the development of indigenized NPP technology. During 1990s, Korea developed KSNP PWR 600 MWe NPP and in the last decade Korea developed APR1400 MWe NPP. Through the time, the engineers and operators involved in every field of nuclear industry is getting old and started to retire. Someone freshly out from the university with bachelor or post graduate degree will take many years to be able to understand how things running and operating in nuclear industry. Even in many years of job assignment, one cannot experience and understand all aspect of nuclear industry. It is this reason to establish a special educational system to teach people already in the field and to be able to see the whole picture by systematically teaching most of the related subject. In order to prevent any influence from existing university system, it was determined to establish KINGS (KEPCO International Nuclear Graduate School) as separate and independent institution and as a post-graduate institution. The curriculum of KINGS was set up along this philosophy, and has only one academic department, for example NPP Engineering Department, to make more interactions among faculty and students. Also the curriculum is set up to teach practical experience; hence the graduates can bridge between industry and academia as well as fill in the large gap of technical experience of older generation. Also another aim is to make KINGS international institution to share experience of Korean NPP development

Start-up of NPP Krsko; Pokusno obratovanje NE Krsko

Energy Technology Data Exchange (ETDEWEB)

Spiler, J; Aralica, J [Nuklearna elektrana Krsko, Krsko (Yugoslavia)

1984-07-01

The report describes a review of start-up program and its realisation. There are also described some more significant start-up results with their evaluation. The most significant operation criteria are compared between NPP Krsko and other similar plants in the world. The comparison shows that after the first contractors and operation personnel efforts have been accomplished, our first nuclear power plant is a safe and reliable source of electric power. At the end there are listed NPP Krsko start-up recommendations and experience. (author)

SAT for NPP personnel training in USA

International Nuclear Information System (INIS)

Spinney, R.

1995-01-01

This discussion addressed the experience with the application of SAT at USA NPPs. In particular, the transition of NPP training processes, staff composition, and reporting structure from the TMI accident to present. As well, oversight and guidance activities of the INPO and more intensive inspection by the NRC began during this period. The average NPP training staff grew to 30-40 per unit, along with a change in reporting line from plant to corporate management. With the reduction of resources occurring in the late 1980s, overall training staff size decreased, the composition changed, and reporting line reverted to plant management. The overall lessons-learned for application of the SAT consisted of the need for simplification, management involvement, and exploitation of the technology

Temporal variability of the NPP-GPP ratio at seasonal and interannual time scales in a temperate beech forest

Directory of Open Access Journals (Sweden)

M. Campioli

2011-09-01

Full Text Available The allocation of carbon (C taken up by the tree canopy for respiration and production of tree organs with different construction and maintenance costs, life span and decomposition rate, crucially affects the residence time of C in forests and their C cycling rate. The carbon-use efficiency, or ratio between net primary production (NPP and gross primary production (GPP, represents a convenient way to analyse the C allocation at the stand level. In this study, we extend the current knowledge on the NPP-GPP ratio in forests by assessing the temporal variability of the NPP-GPP ratio at interannual (for 8 years and seasonal (for 1 year scales for a young temperate beech stand, reporting dynamics for both leaves and woody organs, in particular stems. NPP was determined with biometric methods/litter traps, whereas the GPP was estimated via the eddy covariance micrometeorological technique.

The interannual variability of the proportion of C allocated to leaf NPP, wood NPP and leaf plus wood NPP (on average 11% yr⁻¹, 29% yr⁻¹ and 39% yr⁻¹, respectively was significant among years with up to 12% yr⁻¹ variation in NPP-GPP ratio. Studies focusing on the comparison of NPP-GPP ratio among forests and models using fixed allocation schemes should take into account the possibility of such relevant interannual variability. Multiple linear regressions indicated that the NPP-GPP ratio of leaves and wood significantly correlated with environmental conditions. Previous year drought and air temperature explained about half of the NPP-GPP variability of leaves and wood, respectively, whereas the NPP-GPP ratio was not decreased by severe drought, with large NPP-GPP ratio on 2003 due mainly to low GPP. During the period between early May and mid June, the majority of GPP was allocated to leaf and stem NPP, whereas these sinks were of little importance later on. Improved estimation of seasonal GPP and of the

Advances in safety countermeasures at the Tomari NPP of Hokkaido Electric Power on the basis of Fukushima Daiichi NPP accident. Fire protection and other advances

International Nuclear Information System (INIS)

Shibata, Taku; Dasai, Katsumi

2014-01-01

Fire protections for the nuclear power plants have been based on the fire laws and the conventional guide. After Fukushima Daiichi NPP accident, many safety countermeasures - also about Fire Protection - have been discussed in the Japanese authorities. This paper shows our present activities in the Tomari NPP about the fire protections from the view points of Fire Prevention, Fire Detection/Suppression Systems and Fire Protection, and other advances. (author)

Formulation of chemically reactive foams for the dissolution of oxides polluting the secondary circuits of steam generators

International Nuclear Information System (INIS)

Provens, Helene

1999-01-01

The fouling of the Steam Generators (SG) secondary circuits, due to oxides deposits like magnetite (Fe 3 O 4 ), induces the degradation of the internal SG equipment, the reduction of the plant power, implying to clean these circuits. This operation made in liquid phase generates an important volume of effluents with an expensive cost of treatment. The use of a reactive foam allows the reduction of this volume by ten. Among the reactive tested, oxalic acid is the most efficient to dissolve a magnetite quantity of 10 g.l -1 , at ambient temperature for 24 hours, as imposed by the industrial wishes. The dissolution is not complete in our experimental conditions and is a complex reaction of autocatalytic type, composed of an acid attack, a reductive step, both followed by a slow diffusion. The surfactants generating the foam, which transport the reactive, are adsorbed on the magnetite but this affects weakly the dissolution. Its effectiveness is evaluated varying the experimental conditions. The wetting properties and the stability of the foam induce erosion and undissolved particles transport capacities, during its circulation into the SG. These particles trapped in the inter-bubble liquid films or carried by the piston effect of the foam bed, can be recovered on filters placed out of the SG. To quantify the transport, the influence of different parameters is studied: the more stable the foam is, the more important the transport is. Innocuousness tests showed that oxalic acid was not harmful for constitutive SG materials, either they were isolated or coupled. The cleaning by oxalic acid causes ferrous oxalates precipitation, representing 10 to 15 pc of the total iron quantity depending on the sample. A rinsing out with a foam containing 1 pc oxalic acid and 5 pc hydrogen peroxide allows the dissolution of these precipitates without corrosion problems. (author) [fr

Sludge Lancing IBL: results and experiences in the Spanish NPP's

International Nuclear Information System (INIS)

Montoro, E.; Pozo, C. del

2014-01-01

During the operation cycle of the PWR plants, oxides deposits (sludge) generated in the secondary circuit by erosion corrosion, chemical additives, etc. Which are deposited on the tube plate of GVs, limiting their efficiency and lifespan. To reduce them, Iberdrola Engineering and Construction, together with SRA SAVAC cleaned by high-pressure water means and tele visual inspection between tubes of the GVs. After Sludge Lancing cleanings performed by 250 bar from the center line, an area of solidified sludge remaining on the tubular plate was identified. Late 2010, Iberdrola Engineering and Construction, together with SRA SAVAC developed the Inner Bundle Lancing (IBL) system, which is based on a jet of water of high pressure>500 bar directly impacting areas of hard sludge within the tube bundle to detach and break the deposits into small pieces that can be extracted from GV through a closed circuit suction. (Author)

System for ecological monitoring and assessment for NPP site environment

International Nuclear Information System (INIS)

Vorob'ev, E.I.; Olejnikov, N.F.; Reznichenko, V.Yu.

1987-01-01

On the basis of the Leningrad NPP named after V.I. Lenin the development of a system for ecological monitoring and assessment (EMA) of the environment state and health of personnel and population has started in the EMA program framework. The program of ecological monitoring and assessment coordinates the works on the study of NPP effect on the nature and people, effect of separate factors and their combination, methods and models for the description of the effects, forecasting and evaluation, selection of the optimal protection strategies. Scientific foundations, structure and content of the EMA program are given to coordinate the works carried out according to the program with other works carried out in the country in this direction. The paper deals with the composition of monitoring parameters of the standard system of ecological monitoring of the environment for NPP

Reduction transport of corrosion products through the secondary circuit by increasing the dosage of ammonia; Reduccion del transporte de productos de corrosion a traves del circuito secundario mediante el aumento de la dosificacion de amoniaco

Energy Technology Data Exchange (ETDEWEB)

Espanol, J.; Boronat, M.

2015-07-01

Reduce transport of corrosion products through the Secondary Circuit, mainly magnetite, by increasing the dosage of ammonia in order to reduce oxides accumulation in the Steam Generators top of tube sheet where become hard sludge, as one of the TTS denting mitigation actions. (Author)

NPP Krsko Lifetime Extension - Business Impact for Hrvatska Elektroprivreda

International Nuclear Information System (INIS)

Vrankic, K.; Krejci, M.; Lebegner, J.

2006-01-01

This paper deals with the analysis of possible business impacts for HEP in the case of NPP Krsko life extension. Due to numerous reasons nuclear power plant life extension of ten to twenty years is a common procedure abroad. Having this practise in mind as well as other circumstances in Croatian and Slovenian electric power system, the extension of NPP Krsko lifetime is considered to be a possible scenario. Foreseeable impacts of this decision are evaluated primarily with consideration of its effect on HEPs projected cash flows, though other aspects will be addressed as well. Preserving a well maintained production facility with an extraordinary operational record and stable, or possibly falling overall production costs seems as a very rational choice. This is particularly true having in mind expected rise of electricity demand and energy prices in the region. Having NPP Krsko in operation beyond 2023 implies that no replacement source for NPP Krsko capacity needs to be built. This means avoiding all costs connected with the construction and operation of the replacement plant, assuming it will be fossil fuelled. Due to the high uncertainty of the future fossil fuel prices, the avoidance of replacement plant operational cost is likely to prove as highly rewarding. It should be kept in mind that avoided costs also include the replacement plant greenhouse gases emission costs, thus further enlarging the list of value adding impacts. The latter is valid anticipating the ratification of the Kyoto protocol and joining the European emission trading scheme. In addition to that, the extension of NPP Krsko lifetime would mean that the majority of costs connected with the decommissioning and final waste disposal can be postponed further down the time line. This will have very positive financial and possibly technological impact. Other value creating effects for HEP that are foreseeable as a consequence of the plant lifetime extension include: maintaining the knowledge of

Modernization of the oldest Swedish NPP

International Nuclear Information System (INIS)

Hagberth, Ronald

1998-01-01

OKG operates three BWR units of ABB design: Oskarshamn 1 with a net capacity of 440' MW, Oskarshamn 2 of 600 MW and Oskarshamn 3 of 1160 MW. Oskarshamn 1 NPP was commissioned in 1972 as the first commercial nuclear unit in Sweden. After more than twenty years of successful operation, the unit is now also the first reactor in Sweden to undergo a large safety modernization program. In the year 2000 the Oskarshamn 1 NPP will be modernized to a high level of safety standard and ready for operation for another period of at least 20 years. Experience gained can be used when modernizing other NPPs. The investment program for life extension is reasonable and shows that NPPs can be operated with an expected life span of more than 40 years at an ever-increasing safety level and still be very competitive in a deregulated market. (author)

Factors contribution to the reduction of occupational exposures at Dukovany NPP

International Nuclear Information System (INIS)

Petrova, K.; Urbancik, L.; Fuchsova, D.; Kulich, V.

2008-01-01

This paper describes the causes of achieving such low collective doses and the ways used for a further optimization process reducing occupational exposure at the Dukovany NPP from the beginning of operation up to now. The objective of this contribution is to explain the approaches leading to reduced occupational radiation exposure, measures which have been implemented and what is needed for the maintenance of excellent results in the future. It is possible to identify three main areas and eight main sources affecting collective dose values. There are one objective and two specific causes for low exposures: 1. Objective cause: - General arrangement; - Structural materials; - Fuel integrity. 2. Specific cause influenced by the state regulation: - Legislative support; - Operational safety culture; - Well-though tout system of radiological monitoring; - Effective radiological event feedback; - Effective education and training. 3. Specific cause uninfluenced by the state regulation: - Modified water chemistry of the primary circuit adopted by the licensee; - Licensee's system of radiation work debriefing. All the items specified above contribute to a unique concurrence of circumstances leading to the constantly low occupational exposures at the Czech nuclear power plants. The paper discusses all factors involved in these good results. (authors)

Integrated tool for NPP lifetime management in Spain

Energy Technology Data Exchange (ETDEWEB)

Francia, L. [UNESA, Madrid (Spain); Lopez de Santa Maria, J. [ASCO-Vandellos 2 NPPs l' Hospitalet de l' Infant, Tarragona (Spain); Cardoso, A. [Tecnatom SA, Madrid (Spain)

2001-07-01

The project for the Integrated Nuclear Power Plant Lifetime Management System SIGEVI (Sistema Integrado de GEstion de VIda de Centrales Nucleares) was initiated in April 1998 and finalized in December 2000, the main objective of the project being to develop a computer application facilitating the assessment of the condition and lifetime of nuclear power plant components. This constituted the second phase of a further-reaching project on NPP Lifetime Management. During the first phase of this project, carried out between 1992 and 1995, the methodology and strategy for the lifetime management of the Spanish NPP's were developed. Among others, degradation phenomena were assessed and the most adequate methods for their monitoring were defined. The SIGEVI Project has been performed under the management of UNESA (Spanish Electricity Association) and with the collaboration of different engineering firms and research institutes (Tecnatom, Empresarios Agrupados, Ufisa, Initec and IIT), with Vandellos II as the pilot plant. The rest of the Spanish NPP's have also actively participated through the Project Steering Committee. The following sections describe the scope, the structure and the main functionalities of the system SIGEVI. (authors)

Integrated tool for NPP lifetime management in Spain

International Nuclear Information System (INIS)

Francia, L.; Lopez de Santa Maria, J.; Cardoso, A.

2001-01-01

The project for the Integrated Nuclear Power Plant Lifetime Management System SIGEVI (Sistema Integrado de GEstion de VIda de Centrales Nucleares) was initiated in April 1998 and finalized in December 2000, the main objective of the project being to develop a computer application facilitating the assessment of the condition and lifetime of nuclear power plant components. This constituted the second phase of a further-reaching project on NPP Lifetime Management. During the first phase of this project, carried out between 1992 and 1995, the methodology and strategy for the lifetime management of the Spanish NPP's were developed. Among others, degradation phenomena were assessed and the most adequate methods for their monitoring were defined. The SIGEVI Project has been performed under the management of UNESA (Spanish Electricity Association) and with the collaboration of different engineering firms and research institutes (Tecnatom, Empresarios Agrupados, Ufisa, Initec and IIT), with Vandellos II as the pilot plant. The rest of the Spanish NPP's have also actively participated through the Project Steering Committee. The following sections describe the scope, the structure and the main functionalities of the system SIGEVI. (authors)

Preparation for Early Termination of Ignalina NPP Operation

International Nuclear Information System (INIS)

Poskas, P.; Poskas, R.

2003-01-01

Seimas (Parliament of Lithuania) approved updated National Energy strategy where it is indicated that first Unit will be shutdown before the year 2005 and second Unit in 2009 if funding for decommissioning is available from EU and other donors. In accordance to Ignalina NPP Unit 1 Closure Law the Government of Lithuania approved the Ignalina NPP Unit 1 Decommissioning Program until year 2005. For enforcement of this program, the plan of measures for implementation of the program was prepared and approved by the Minister of Economy. The plan consists of two parts, namely technical- environmental and social-economic. Technical-environmental measures are mostly oriented to the safe management of spent nuclear fuel and operational radioactive waste stored at the plant and preparation of licensing documents for Unit 1 decommissioning. Social-economic measures are oriented to mitigate negative social and economic impact on Lithuania, inhabitants of the region, and, particularly, o n the staff of Ignalina NPP by means of creating favorable conditions for a balanced social and economic development of the region. In this paper analysis of planned activities, licensing requirements for decommissioning, progress in preparation of the Final Decommissioning Plan is discussed

Short- circuit tests of circuit breakers

OpenAIRE

Chorovský, P.

2015-01-01

This paper deals with short-circuit tests of low voltage electrical devices. In the first part of this paper, there are described basic types of short- circuit tests and their principles. Direct and indirect (synthetic) tests with more details are described in the second part. Each test and principles are explained separately. Oscilogram is obtained from short-circuit tests of circuit breakers at laboratory. The aim of this research work is to propose a test circuit for performing indirect test.

Electrical equivalent circuit of an ion-exchange membrane system

Energy Technology Data Exchange (ETDEWEB)

Nikonenko, Victor V., E-mail: v_nikonenko@mail.r [Membrane Institute, Kuban State University, Krasnodar (Russian Federation); Kozmai, Anton E. [Membrane Institute, Kuban State University, Krasnodar (Russian Federation)

2011-01-01

Usually, the current flowing through an electrochemical cell is divided into the faradaic current going to an electrochemical interface reaction, and the current charging electric double layer (EDL). This division leads to the Randles-Ershler equivalent circuit with an EDL capacitance in one branch, and the faradaic impedance in the other, specific for each particular system. However, the physics of the separation of the impedance into faradaic and capacitive components for different electrochemical systems is not sufficiently clear. The most of derivations resulting in the formal construction of the Randles-Ershler or similar equivalent circuits are based on the a priori separation of the electroneutral and the double-layer regions. In this paper, we derive an equation for the impedance of a three-layer system consisted of an ion-exchange membrane and two adjoining diffusion boundary layers (DBL) starting from the Poisson equation. The system is polarized by a constant electric current over which a small sinusoidal signal is applied. The equation shows that the impedance of the considered system can be formally interpreted via an equivalent circuit with a frequency dependent capacitance in one branch and a finite-length Warburg-type impedance in the other. To take into account this dependence, the impedance of the system may be presented as a series connection of five circuits. Three of them are consisted of a geometric capacitance connected in parallel with an ohmic resistance, respectively, for both diffusion layers and for the membrane bulk; the two others being the double-layer capacitance in parallel with the finite-length Warburg impedance for the left and the right interfaces, respectively. The comparison of the impedance spectra calculated within our analytical approach with those obtained by the full numerical solution of the Nernst-Planck-Poisson (NPP) equations shows a good agreement. Different possible situations, which might arise in real systems

Assessment of financial expenditure for Rivne NPP power units decommissioning

International Nuclear Information System (INIS)

Nosovskij, A.V.; Salij, L.M.

2007-01-01

The article covers some financial aspects of developing a decommissioning concept for Rivne NPP power units with reactor VVER-440 and VVER-1000. Possible methodological approaches to costs estimate have been analyzed. Preliminary results of cost estimation are presented for two decommissioning options: deferred and immediate dismantling. Principally possible options for accumulating assets have been analyzed to finance measures related to Rivne NPP decommissioning. A mathematical model has been proposed for creating decommissioning financial reserve

The negative differential resistance characteristics of an RC-IGBT and its equivalent circuit model

International Nuclear Information System (INIS)

Zhang Wenliang; Zhu Yangjun; Tian Xiaoli; Lu Shuojin

2014-01-01

A simple equivalent circuit model is proposed according to the device structure of reverse conducting insulated gate bipolar transistors (RC-IGBT). Mathematical derivation and circuit simulations indicate that this model can explain the snap-back effect (including primary snap-back effect, secondary snap-back effect, and reverse snap-back effect) and hysteresis effect perfectly. (semiconductor devices)

On improving the NPP construction long-term planning

International Nuclear Information System (INIS)

Solov'ev, M.M.

1980-01-01

General approaches to solving the problems of long-term planning of the construction-mounting work volume and introduction of power capacities at different paces of power unit commission and norms of construction time are considered. Problems associated with location and development of subsidiary industries providing NPP construction are discussed. It is shown that decrease of WWER-1000 reactor type NPP construction time from 24 to 12 months results in reduction of required high-skilled engineers, managerial staff, unique construction mechanisms and engines as well as in improvement of conditions for conducting measures on work arrangement during preparation of construction industry and mounting of the first assemblies

Tendencies of ecological changes in the region of Ignalina NPP and in Lake Drukshiai

International Nuclear Information System (INIS)

Pashkauskas, R.; Mazeika, J.; Baubinas, R.

1999-01-01

Since 1979, when the construction of the Ignalina Nuclear Power Plant started, a group of specialists from Lithuania research and academic institutions began to investigate both Lake Drukshiai - the cooler of the Ignalina NPP and the neighbouring area. The investigations were aimed not only at monitoring the environmental consequences of the Ignalina NPP impact but also at forecasting changes of the ecosystems. The State Scientific Program 'Ignalina Nuclear Power Plant and the Environment' was the result of final stage of complex investigations. This conference paper contains data on the changes of thermal state and water balance of Lake Drukshiai, the effect of permanent thermal and chemical pollution on the chemical composition and hydrochemical regime, the pollution of the lake water, the geochemical-contaminated state, the condition, dynamics and the changes of hydrobiont communities in Lake Drukshiai. Radioecological and eco toxicological state of Ignalina NPP region and Lake Drukshiai is estimated as well as changes in Lake Drukshiai and Ignalina NPP surrounding area ecosystems under the combine anthropogenic impact of the plant influence are elucidated. The findings on medical and biological studies in the Ignalina NPP influence population zone and the evidence of impact of Ignalina NPP on social-territorial processes in the region are presented as well

Calculation model for 16N transit time in the secondary side of steam generators

International Nuclear Information System (INIS)

Liu Songyu; Xu Jijun; Xu Ming

1998-01-01

The 16 N transit time is essential to determine the leak-rate of steam generator tubes leaks with 16 N monitoring system, which is a new technique. A model was developed for calculation 16 N transit time in the secondary side of steam generators. According to the flow characters of secondary side fluid, the transit times divide into four sectors from tube sheet to the sensor on steam line. The model assumes that 16 N is moving as vapor phase in the secondary-side. So the model for vapor velocity distribution in tube bundle is presented in detail. The 16 N transit time calculation results of this model compare with these of EDF on steam generator of Qinshan NPP

Development of circuit model for arcing on solar panels

International Nuclear Information System (INIS)

Mehta, Bhoomi K; Deshpande, S P; Mukherjee, S; Gupta, S B; Ranjan, M; Rane, R; Vaghela, N; Acharya, V; Sudhakar, M; Sankaran, M; Suresh, E P

2010-01-01

The increased requirements of payload capacity of the satellites have resulted in much higher power requirements of the satellites. In order to minimize the energy loss during power transmission due to cable loss, use of high voltage solar panels becomes necessary. When a satellite encounters space plasma it floats negatively with respect to the surrounding space plasma environment. At high voltage, charging and discharging on solar panels causes the power system breakdown. Once a solar panel surface is charged and potential difference between surface insulator and conductor exceeds certain value, electrostatic discharge (ESD) may occur. This ESD may trigger a secondary arc that can destroy the solar panel circuit. ESD is also called as primary or minor arc and secondary is called major arc. The energy of minor arc is supplied by the charge stored in the coverglass of solar array and is a pulse of typically several 100 ns to several 100 μs duration. The damage caused by minor arc is less compared to major arcs, but it is observed that the minor arc is cause of major arc. Therefore it is important to develop an understanding of minor arc and mitigation techniques. In this paper we present a linear circuit analysis for minor arcs on solar panels. To study arcing event, a ground experimental facility to simulate space plasma environment has been developed at Facilitation Centre for Industrial Plasma Technologies (Institute for Plasma Research) in collaboration with Indian Space Research Organization's ISRO Satellite Technology Centre (ISAC). A linear circuit model has been developed to explain the experimental results by representing the coverglass, solar cell interconnect and wiring by an LCR circuit and the primary arc by an equivalent LR circuit. The aim of the circuit analysis is to predict the arc current which flows through the arc plasma. It is established from the model that the current depends on various parameters like potential difference between insulator

Problems of complex automation of process at a NPP

International Nuclear Information System (INIS)

Naumov, A.V.

1981-01-01

The importance of theoretical investigation in determining the level and quality of NPP automation is discussed. Achievements gained in this direction are briefly reviewed on the example of domestic NPPs. Two models of the problem solution on function distribution between the operator and technical means are outlined. The processes subjected to automation are enumerated. Development of the optimal methods of power automatic control of power units is one of the most important problems of NPP automation. Automation of discrete operations especially during the start-up, shut-down or in imergency situations becomes important [ru

The NPP Isar comprehensive Aging Management Program

International Nuclear Information System (INIS)

Zander, Andre; Ertl, Stefan

2012-01-01

The majority of System, Structure and Components (SSC) in a nuclear power plants are designed to experience a service life, which is far above the intended design life. In most cases, only a small percentage of SSCs are subject to significant aging effects, which may affect the integrity or the function of the component. The process of aging management (AM) has the objective to monitor and control degradation effects which may compromise safety functions of the plant. And furthermore, to ensure, that testing and maintenance programs sufficiently provide preventive measures to control degradation effects. Safety-related aspects and the targeted high availability of the power plant as well as the requirements stipulated by German regulatory authorities prompted the operator of NPP ISAR to introduce an aging surveillance program. The NPP Isar as well as the German NPPs has to be following in the scope of aging management the KTA 1403 guideline. The NPP Isar surveillance program based on the KTA 1403 guideline covers the following aspects: - Scoping and screening of safety relevant Systems, Structures and Components (SSC); - Identification of possible degradation mechanisms for safety relevant SSC; - Ensure, that testing and maintenance programs sufficiently provide preventive measures to control degradation effects; - Transferability check of industry experience (internal and external events); - Annual preparation of an AM status report. (author)

European cooperation under the modernization program of the Kozloduy NPP units 5 and 6 and its evolution during the Belene NPP construction

International Nuclear Information System (INIS)

Hoch, G.

2005-01-01

The major part of the modernization program for the Kozloduy NPP units 5 and 6 is being performed by the European Consortium Kozloduy (ECK), consisting of AREVA - FRAMATOME ANP (Germany and France) and Atomenergoexport (Russia). The ECK main project, consisting of 76 separate measures, shall be finished in the first half of 2006. One of the major tasks was to form the different teams on contractors and employers side such that the works can be executed effectively in a timely manner and as per the technical and quality requirements. Different actions were undertaken on both sides in order to assure the main target, namely to implement the complete scope of work within the contractual time schedule. So far it can be reported that the teams have successfully worked and as a matter of fact at present more than 100 outage days have been saved compared to the initial contractual time schedule. This important result is based on different success factors in the field of planning, engineering and design, outage organization, implementation including testing and commissioning, quality assurance. After the decision of Bulgaria to continue the erection of Belene NPP, a bidding consortium has been founded by the ECK Consortium members, in order to provide a joint offer for this project. The good reputation, expertise and the experience gained from the Kozloduy NPP units 5 and 6 modernization project together with a reliable network with Bulgarian industrial partners may contribute the utmost to a successful finalization of the Belene NPP. (author)

Probabilistic assessment of the Juragua NPP response under Station Blackout conditions

International Nuclear Information System (INIS)

Valhuerdi Debesa, C.; Vilaragut Llanes, J.J.

1996-01-01

Assessment of the NPP response under SBO (station Blackout) conditions is a current safety issue of special interest, In the case of Juragua NPP, the safety assessment related to this topic is very important, taking into account the peculiarities of the Cuban Electro energetic System: small and long island, without possibilities of conexion beyond its borders and under the incidence of tropical phenomena In this papers a preliminary evaluation is presented of the potential incidence of Station Blackout conditions for Juragua NPP. the importance of this sort of events for the safety of the plant is evaluated, the factors which condition it are identified and measures for its prevention or recovering the normal situation if such an event takes place are proposed

Modernization of tritium in air monitoring system for CANDU type NPP

International Nuclear Information System (INIS)

Purghel, L.; Iancu, R.; Popescu, M.

2009-01-01

Nuclear energy provides at present one third of Europe's electricity with nearly no greenhouse-gas emissions. Sustained efforts are now being conducted to harmonize regulations all over Europe through WENRA and to converge on technical nuclear safety practices within the TSO network ETSON (European Technical Safety Organizations Network). In order to achieve this goals of safety function, IFIN-HH together with CITON developed a new solution to improve the Tritium Monitoring System (TMS) of Cernavoda NPP and the new generation of CANDU type reactors, using Tritium in air Intelligent Monitors (TIM) developed and patented by IFIN-HH. The paper presents a comparative analysis between the technical characteristics of traditional solutions implemented in CANDU type NPP, particularly in Cernavoda NPP Unit 2 and the newly proposed solution. (authors)

Turkish Students' Conceptions about the Simple Electric Circuits

Science.gov (United States)

Cepni, Salih; Keles, Esra

2006-01-01

In this study, the Turkish students' understanding level of electric circuits consisting of two bulbs and one battery was investigated by using open-ended questions. Two-hundred fifty students, whose ages range from 11 to 22, were chosen from five different groups at primary, secondary and university levels in Trabzon in Turkey. In analyzing…

Test research and analysis for ultimate capacity of Qinshan NPP PCCV

International Nuclear Information System (INIS)

Zufeng, X.

1994-01-01

This paper introduces design and research for containment of Qinshan NPP which is the first PWR in CHINA designed and constructed by ourselves. The PCCV design is basically in conformity to ASME code. To verify the structural integrity capacity of Qinshan NPP containment, we fulfilled SIT and ILRT successfully in June, 1991. The special attention of the paper is focused on the ultimate capacity of the PCCV under severe accidents and earthquake. A study comprised of five different independent parts has been performed for the development of containment model test and corresponding nonlinear analysis. There are two prestressed concrete containment models with equipment hatch. One is 1/15 scale with steel liner tested on shake table and then moved out loaded with atmospheric pressure. The other is 1/10 scale without steel liner loaded with water pressure until destruction. From different methods including model test and nonlinear analysis, all obtained unanimous conclusion. The capacity under internal pressure and earthquake is reliable. The safety margin is enough. Consequently, in the second phase of Qinshan NPP and other PWR NPP under design, PCCV should be a better selection in China since it's more economic, rational and safe. (author)

Contribution of the Slovak University of Technology Bratislava to the Education of NPP Operation Staff in Slovakia

International Nuclear Information System (INIS)

Hascik, J.; Slugen, V.; Hinca, R.; Miglierini, M.

2006-01-01

Paper is focused on the preparation of NPP VVER -440 staff in Slovak conditions. The realisation is managed via special technical courses, seminars, workshops, and trainings on selected experimental facilities at domestic as well as international level. Post-gradual re-qualification study: Safety aspects of NPP operation is discussed in detail. Six-year experience with NPP operating staff education can be shared and recommended also at international level. Based on these courses, special training for optimal preparation of NPP supervising physicists was started in 2002. In addition to all our activities, the international course: Safety aspects of NPP operation for subcontractors was prepared and realised in 2005.(author)

Seismic site evaluation practice and seismic design guide for NPP in Continent of China

Energy Technology Data Exchange (ETDEWEB)

Yuxian, Hu [State Seismological Bureau, Beijing, BJ (China). Inst. of Geophysics

1997-03-01

Energy resources, seismicity, NPP and related regulations of the Continent of China are briefly introduced in the beginning and two codes related to the seismic design of NPP, one on siting and another on design, are discussed in some detail. The one on siting is an official code of the State Seismological Bureau, which specifies the seismic safety evaluation requirements of various kinds of structures, from the most critic and important structures such as NPP to ordinary buildings, and including also engineering works in big cities. The one on seismic design of NPP is a draft subjected to publication now, which will be an official national code. The first one is somewhat unique but the second one is quite similar to those in the world. (author)

Seismic site evaluation practice and seismic design guide for NPP in Continent of China

International Nuclear Information System (INIS)

Hu Yuxian

1997-01-01

Energy resources, seismicity, NPP and related regulations of the Continent of China are briefly introduced in the beginning and two codes related to the seismic design of NPP, one on siting and another on design, are discussed in some detail. The one on siting is an official code of the State Seismological Bureau, which specifies the seismic safety evaluation requirements of various kinds of structures, from the most critic and important structures such as NPP to ordinary buildings, and including also engineering works in big cities. The one on seismic design of NPP is a draft subjected to publication now, which will be an official national code. The first one is somewhat unique but the second one is quite similar to those in the world. (author)

Situation analysis of physical independence of the equipment and safety circuits of Almaraz NPP regarding R.G. 1.75 rev.3 (2005)

International Nuclear Information System (INIS)

Seijas Portela, S.

2010-01-01

Situation analysis of physical independence of the electrical equipment and circuits CN safety Almaraz about R.G. 1.75 rev. 3. (2005) The aim of this paper is to present the work done in the analysis of the physical separation of redundant safety electrical equipment (emergency diesel generators, medium voltage, electrical cabinets, etc.) and physical separation of circuits and electrical conduits.

Financing Nuclear Projects. Case Study: Unit 2 Cernavoda NPP

International Nuclear Information System (INIS)

Chirica, Teodor; Constantin, Carmencita; Dobrin, Marian

2003-01-01

The implementation of a Nuclear Power Plant (NPP) is a major undertaking for all entities involved, due to the necessity of planning work and coordination of the implementation process of the different fields of interest, starting with the governmental authorities and ending with the public. Having in view the specific investment costs (relatively high) for a NPP, finding an adequate financing structure is possible through an iterative process that involves first an assessment of the technical performances of the project and secondly, the mathematical modelling of the financing structure effects on the projects. In this respect, the paper will be focused on the main steps needed in order to promote an investment project in nuclear field, starting with the decision phase, providing the documentation requested by the local and international authorities to promote the project and ending with the negotiation of the contracts (commercial contract, financing contract, purchase contract, etc). The case study will be focused on the phases achieved in order to promote the Unit 2 NPP Cernavoda completion works project. (authors)

Financing nuclear projects. Case study: Unit 2 Cernavoda NPP

International Nuclear Information System (INIS)

Chirica, T.; Pall, S.; Lebedev, A.; Dobrin, M.

2003-01-01

The implementation of a Nuclear Power Plant (NPP) in a country is a major undertaking for all entities involved, due to the necessity of planning work and co-ordination of the implementation process of the different fields of interest, starting with the governmental authorities and ending with the people. Having in view the specific investment cost (relatively high) for a NPP, to find an adequate financing structure is possible through an iterative process that involves first an assessment of the technical performances of the project and second, the mathematical modelling of the financing structure effects on the project. In this respect, the paper proposed will be focused on the main steps needed in order to promote an investment project in nuclear field, starting with the decision phase, providing the documentations requested by the local and international authorities to promote the project and ending with the negotiation of the contracts (commercial contract, financing contract, power purchase contract, etc.) The case study will be focused on the phases achieved in order to promote the Unit 2 Cernavoda NPP completion works project. (author)

Fiddle at financing of Mochovce NPP

International Nuclear Information System (INIS)

Beer, G.

2003-01-01

Slovak police found out and documented racket in financing of third and fourth block of Mochovce NPP. Damage should be 144 millions Slovak crowns. Investigator consequently accused twenty-three Slovaks from foundation, trump up and supporting of criminal group and deception. Two persons are suggested to be taken to custody. Skoda Praha, which was general supplier of construction for 1,5 billions Slovak crowns, in 2001 allowed to create a connection to let the finances between Slovenske elektrarne, a.s., Bratislava as investor and Skoda as subcontractor to be paid through three mediator companies. Companies got authorization to balance the relationship among all interested subjects. Confused network of 118 treaties was created. They invoiced reward from money current based on these treaties. Reward represented up to 70 per cent of transferred resources in some cases. According to Minister of Domestic Affairs Vladimir Palko it will be necessary to find out where is actually the money. For the time being nobody from NPP is among accused. (Author)

The installation of a modern training facility for the Kalinin NPP

International Nuclear Information System (INIS)

Parfenov, A.; Gronau, D.; Birnie, S.

1996-01-01

Kalinin NPP Management has initiated an ambitious programme of improvements to its overall training commitment. With the assistance of the consultancy services provided by Siemens, it is planned to realize this programme in terms of training and training premises conforming to the stated goal of the NPP Management, on a timescale only made possible by adopting a pragmatic approach to the systematic approach to training. 1 ref

NPP safety and personnel training. XII International conference. Abstracts. Volume 2

International Nuclear Information System (INIS)

2011-01-01

The XII International conference NPP Safety and Personnel Training took place in Obninsk, October 4-7 2011. The problems of personnel training for nuclear industry are discussed. The innovation nuclear systems and fuel cycle are considered. The much attention has been given to NPP radiation safety and radioecology issues. The recent high-speed computation and simulation methods used in reactor technology are presented [ru

Remote technology in RBMK-1000 spent fuel management at NPP site

International Nuclear Information System (INIS)

Makarchuk, T.F.; Kozlov, Y.V.; Tikhonov, N.S.; Tokarenko, A.I.; Spichev, V.V.; Kaljazin, N.N.

1999-01-01

The report describes the remote technologies employed in the nuclear power plant with RBMK-1000 type. Spent fuel transfer and handling operations at reactor (AR) and away from reactor (AFR) on reactor site (RS) facilities are illustrated by the example of the Leningradskaya NPP and are typical for all NPPs with RBMK-1000. The current approach to spent fuel management at NPP sites is also presented. (author)

The main trends of work on ageing and lifetime management of NPP

International Nuclear Information System (INIS)