Use of Level 1 PSA in the Frame of EPR Licensing

2014 ◽  
Author(s):  
Gabriel Georgescu ◽  
Patricia Dupuy ◽  
Francois Corenwinder
Keyword(s):  
Probabilistic Methods ◽  
Spent Fuel ◽  
Pressurized Water ◽  
Spent Fuel Pool ◽  
Level 1 ◽  
Water Reactors ◽  
High Level ◽  
Design Construction

The French “Technical Guidelines for the design and construction of the next generation of NPPs with Pressurized Water Reactors” specify that the safety demonstration has to be achieved in a deterministic way, supplemented by probabilistic methods. In this context, for the EPR reactor of Flamanville (EPR-FA3), the PSA has been used from the beginning of the design. In the frame of the application for commissioning of EPR-FA3, EdF has to provide an “as-build” full scope PSA for the reactor and for the spent fuel pool, covering the internal events, as well as the internal and external hazards of significant impact. Some of these probabilistic studies were developed and evolved during the EPR design (PSA for “internal events”, specific studies for practically eliminated sequences, long term accident sequences…) and were analysed by IRSN, as French Safety Authority (ASN) technical support, at different EPR project stages (initial design, detailed design, construction application….) leading to many design and studies improvements. Today, in order to make the analysis of the application for the commissioning of the EPR-FA3 reactor more effective, the “anticipated” analysis of this application is in progress in France. In this context, the updated versions of the level 1 probabilistic studies for internal events and hazards were analysed by IRSN in 2013. The results and conclusions of this analysis were presented by IRSN early 2014 during a dedicated meeting of French Standing Group of experts for Reactors safety (SGR). The paper presents the analysis performed by IRSN of EdF EPR-FA3 level 1 probabilistic studies, highlighting the role of PSA to the achievement of high level of safety of EPR reactor.

Research on the Radioactivity of Thorium Fuel in Different Reactors

2008 ◽  
Author(s):  
Ganglin Yu ◽  
Kan Wang
Keyword(s):  
Fuel Cycle ◽  
Research Work ◽  
Fission Products ◽  
Spent Fuel ◽  
Short Term ◽  
Pressurized Water ◽  
Actual Application ◽  
Water Reactors ◽  
The Difference

It’s very important to estimate the mass and radiotoxicity of isotopes in spent fuel of thorium fuel cycle, which will benefit the application of the thorium fuel. Much research work has been done on the spent fuel and radioactivity of thorium-based fuel before, yet the difference in usage is always ignored. This paper studies the raise of isotopes in spent fuel of thorium-based fuel cycle in pressurized water reactors and fast neutron reactors, focus on the radioactivity level of actinides and fission products, the important nuclides which have long term radiological impact or give the highest contribution to the total dose on short term after different decay periods. The paper discuss the important nuclides in the measurement of thorium fuel burnup, the conclusion will benefit the actual application of thorium fuel.

scholarly journals 14C Release in Various Chemical Forms With Gaseous Effluents From the Paks Nuclear Power Plant

Radiocarbon ◽  
1989 ◽  
Vol 31 (03) ◽  
pp. 754-761 ◽  
Author(s):  
Ede Hertelendi ◽  
György Uchrin ◽  
Peter Ormai
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Liquid Scintillation ◽  
Mean Value ◽  
Scintillation Counting ◽  
Pressurized Water ◽  
The Mean ◽  
Water Reactors

We present results of airborne 14C emission measurements from the Paks PWR nuclear power plant. Long-term release of 14C in the form of carbon dioxide or carbon monoxide and hydrocarbons were simultaneously measured. The results of internal gas-proportional and liquid scintillation counting agree well with theoretical assessments of 14C releases from pressurized water reactors. The mean value of the 14C concentration in discharged air is 130Bqm-3 and the normalized release is equal to 740GBq/GWe · yr. > 95% of 14C released is in the form of hydrocarbons, ca 4% is apportioned to CO2, and <1% to CO. Tree-ring measurements were also made and indicated a minute increase of 14C content in the vicinity of the nuclear power plant.

scholarly journals Criticality safety analysis of spent fuel pool for a PWR using UO2, MOX, (Th-U)O2 and (TRU-Th)O2 fuels

2019 ◽  
Vol 7 (3A) ◽  
Author(s):  
Claubia Pereira ◽  
Jéssica P. Achilles ◽  
Fabiano Cardoso ◽  
Victor F. Castro ◽  
Maria Auxiliadora F. Veloso
Keyword(s):  
Normal Operation ◽  
Pressurized Water Reactor ◽  
Spent Fuel ◽  
Pressurized Water ◽  
Operation Conditions ◽  
Transport Code ◽  
Uranium Fuel ◽  
Fuel Assemblies ◽  
Spent Fuel Pool ◽  
Criticality Safety

A spent fuel pool of a typical Pressurized Water Reactor (PWR) was evaluated for criticality studies when it uses reprocessed fuels. PWR nuclear fuel assemblies with four types of fuels were considered: standard PWR fuel, MOX fuel, thorium-uranium fuel and reprocessed transuranic fuel spiked with thorium. The MOX and UO2 benchmark model was evaluated using SCALE 6.0 code with KENO-V transport code and then, adopted as a reference for other fuels compositions. The four fuel assemblies were submitted to irradiation at normal operation conditions. The burnup calculations were obtained using the TRITON sequence in the SCALE 6.0 code package. The fuel assemblies modeled use a benchmark 17x17 PWR fuel assembly dimensions. After irradiation, the fuels were inserted in the pool. The criticality safety limits were performed using the KENO-V transport code in the CSAS5 sequence. It was shown that mixing a quarter of reprocessed fuel withUO2 fuel in the pool, it would not need to be resized 

Investigating sponsor decision-making: the role of schema theory, agency conflicts, and signaling theory in the persistence of naming rights agreements

2020 ◽  
Vol 21 (3) ◽  
pp. 467-486 ◽  
Author(s):  
Jonathan A. Jensen ◽  
David Head ◽  
Christopher Mergy
Keyword(s):  
Decision Making ◽  
Schema Theory ◽  
Agency Conflicts ◽  
Data Set ◽  
Content Type ◽  
Naming Rights ◽  
High Level ◽  
Sport Facilities

PurposeNaming rights sponsorships of sport facilities are among the most highly visible marketing agreements in the world. However, factors that may lead one sponsorship to persist for decades, while others end after just a few years, have yet to be investigated. Thus, this study examines the decision-making of brand marketers by investigating the predictors of a sponsoring brand's decision to either continue or dissolve such agreements.Design/methodology/approachUtilizing a global data set of 219 naming rights agreements, an empirical approach is utilized to isolate whether a variety of factors increase or decrease the probability of sponsorship dissolution.FindingsResults indicate that agreements entered into with new, as of yet-unnamed facilities lead to a reduction in the probability of dissolution, with a high level of brand equity also reducing the probability of dissolution. Agency conflicts may also play a role, as the sponsoring firm being headquartered in the same metropolitan area as the facility also contributes to the persistence of such agreements.Originality/valueThese results are intended to assist both sides of what is ideally a long-term relationship in better understanding the factors that may either contribute to or inhibit longer-term partnerships.

On the Role of H2 as an Inhibitor of UO2 Matrix Dissolution

2007 ◽  
Author(s):  
Juan Merino ◽  
Xavier Gaona ◽  
Lara Duro ◽  
Jordi Bruno ◽  
Aurora Marti´nez-Esparza
Keyword(s):  
Chemical Composition ◽  
Partial Pressure ◽  
Water Radiolysis ◽  
Water Interface ◽  
Spent Fuel ◽  
Dissolution Rates ◽  
Term Stability ◽  
Long Term Stability

The study of spent fuel behaviour under disposal conditions is usually based on conservative approaches assuming oxidising conditions produced by water radiolysis at the fuel/water interface. However, the presence of H2 from container corrosion can inhibit the dissolution of the UO2 matrix and enhance its long-term stability. Several studies have confirmed the decrease in dissolution rates when H2 is present in the system, although the exact mechanisms of interaction have not been fully established. This paper deals with a radiolytic modelling exercise to explore the consequences of the interaction of H2 with radicals generated by radiolysis in the homogeneous phase. The main conclusion is that in all the modelled cases the presence of H2 in the system leads to a decrease in matrix dissolution. The extent of the inhibition, and the threshold partial pressure for the inhibition to take place, both depend in a complex way on the chemical composition of the water and the type of radiation present in the system.

What really happens to the “vanishing overpack”?

2012 ◽  
Vol 1475 ◽  
Author(s):  
I. G. McKinley ◽  
F. B. Neall ◽  
E. M. Scourse ◽  
H. Kawamura
Keyword(s):  
Radionuclide Transport ◽  
Spent Fuel ◽  
Geological Disposal ◽  
Failure Times ◽  
Bentonite Buffer ◽  
Physical Barriers ◽  
Safety Assessments ◽  
High Level ◽  
Radionuclide Release

ABSTRACTConcepts for the disposal of high-level radioactive waste (HLW) and spent fuel (SF) in several countries include a massive steel overpack within a bentonite buffer. In past conservative safety assessments to demonstrate feasibility of geological disposal, overpacks are assumed to provide complete containment for a given lifetime, after which all fail simultaneously. After failure, they are ignored as physical barriers to radionuclide transport. In order to compare different repository designs for specific sites, however, a more realistic treatment of overpack failure and its subsequent behaviour is needed. In addition to arguing for much longer lifetimes before mechanical failure and a distribution of overpack failure times, such assessment indicates that the presence of the failed overpack greatly constrains radionuclide release from the waste matrix and subsequent migration through the engineered barrier system. It also emphasises the key role of the bentonite buffer and the need to be able to assure its performance over relevant timescales.

An Introduction to RCC-C: An AFCEN Code for Design and Construction of PWR Fuel Assemblies

2013 ◽  
Author(s):  
Christine Vauglin ◽  
Marc Ton-That ◽  
Morello Sperandio ◽  
Denis Buisine
Keyword(s):  
French Society ◽  
Pressurized Water ◽  
Technical Content ◽  
Fuel Assemblies ◽  
Core Components ◽  
Mechanical Components ◽  
Water Reactors ◽  
Design Characteristics ◽  
Service Inspection ◽  
Design Construction

AFCEN is the French society which publishes codes for design, construction and in-service inspection rules for Pressurized Water Reactors. The fields covered by theses codes are: mechanical components, in-service surveillance of mechanical components, electrical equipments, nuclear fuel, and more recently, civil works and fire protection. After a brief global presentation of AFCEN history and current position, we set out the technical content of one of these codes: RCC-C. This code is dedicated to fuel assemblies and associated core components. It sets forth minimum generic requirements to be met by the supplier and by the manufacturer for the design justifications and for the manufacturing and inspection operations of PWR fuel assemblies and rod cluster control assemblies. We go over the different chapters of RCC-C: product and part characteristics; manufacturing and inspection processes and methods and associated qualifications; inspection requirements for the different items; design characteristics and requirements which the design justification shall meet; methods for demonstrating that design requirements are met.

scholarly journals The prevalence of risk factors of cardiovascular diseases in persons with arterial hypertension exposed to occupational stress

2017 ◽  
Vol 95 (6) ◽  
pp. 535-544
Author(s):  
A. I. Telegina ◽  
R. A. Liferov ◽  
A. Ya. Fisun ◽  
R. G. Makiev ◽  
V. V. Gornov ◽  
...  
Keyword(s):  
Risk Factors ◽  
Occupational Stress ◽  
Emotional Stress ◽  
Cardiovascular Complications ◽  
Leading Role ◽  
High Prevalence ◽  
Atherosclerotic Process ◽  
High Level

Based on the literature data and the results of their own research, the authors emphasize the importance of studying adverse effects of high emotional load during stress-induced hypertension and draw attention to the high prevalence of modifiable risk factors of cardiovascular disease among servicemen exposed to occupational stress. It has been shown that lifestyle of hypertensive subjects under heavy stress is characterized by irrational changes in eating behavior, high prevalence of smoking, increased alcohol consumption, and low physical activity. The leading role of long-term emotional stress was demonstrated as an independent risk factor of hypertension in servicemen exposed to long-term occupational psycho-emotional stress. Analysis of the intima-media complex thickness in brachiocephalic arteries, depending on the level of psychosocial stress demonstrated that the group of the examined servicemen with hypertension showed changes that might be due to the development of atherosclerotic process, the response to increased flow, and arterial wall tension at a high level of stress. These changes are unidirectional regardless of the duration of hypertension history. Results of evaluation of the overall risk of developing cardiovascular complications based on the SCORE scale in the servicemen with established and newly diagnosed hypertension under heavy stress suggest its enhancement in the next 10 years which makes necessary implementation of a system of measures for preventing and correcting pathological conditions caused by stressful loads. Stratification of risk factors is essential for early diagnosis of hypertension and the choice of adequate therapy in subjects undergoing high psycho-emotional stress.

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