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Laboratory of Nuclear Installations Safety (17) - part_2
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Scientific Divisions / Laboratory of Nuclear Installation Safety (17)

Laboratory of nuclear installation safety (17)

Laboratory Chief

Dr. Habil. Eugenijus Ušpuras

Breslaujos 3, LT-44403 Kaunas

Phone +370 (37) 401 926
Fax     +370 (37) 351 271
Eugenijus.Uspuras


MAIN RESEARCH AREAS OF THE LABORATORY:
 
    safety assessment of nuclear power plants;
    safety analysis of thermonuclear fusion reactors;
    analysis of new generation nuclear power plants;
    analysis of thermal-hydraulic accident and transient processes;
    assessment of change of thermal-hydraulic parameters in NPP containments and other premises;
    simulation of transport of radionuclides and aerosols in premises;
    analysis of reactivity initiated accident processes of nuclear reactor and justification of modifications in reactor core;
    safety assessment of decommissioning and dismantling of nuclear installations;
    reliability estimation and control of energy systems;
    level 1 and level 2 probabilistic safety assessment of NPPs;
    strength analysis of structures, piping and components in complex technical systems;
    failure analysis and engineering assessment for complex technical systems;
    risk and hazard assessment of industrial objects;
    assessment of security of energy supply;
    modeling and reliability assessment of processes in energy supply networks;
    probabilistic modeling and analysis of unusual events;
    analysis of sensitivity and uncertainty of modeling results;
    fundamental research in thermal physics.
 
In 2016, researchers of the Laboratory together with other national and foreign partners were implementing 24 projects: three research projects funded by the state budget subsidy; one long-term institutional R&D program; 16 international projects (5 projects in FP7 and 6 projects in Horizon 2020); 4 projects ordered by Lithuanian economy subjects and state institutions.
 
 
1. LITHUANIAN REPUBLIC GOVERNMENT FUNDED PROJECTS
 
   LONG-TERM INSTITUTIONAL R&D PROGRAMS

In 2016, a five-year long-term institutional research and development program Scientific research of safety important processes in nuclear and nuclear fusion facilities, was completed. The objective of this program is to prepare a complex safety assessment methodology for deterministic and probabilistic analysis of nuclear fission and fusion installations with regard to uncertainties and severe accident scenarios. The performed work is complex; here, integrated deterministic and probabilistic analysis methodology is developed and applied for safety assessment encompassing the fields of neutron kinetics, thermal-hydraulics, strength analysis, material science, and mathematical modelling.

Investigation on suitability of tools used for deterministic accident analysis of new generation nuclear reactors and nuclear fusion facilities was summarised, application of computer code RELAP5 for modelling of boiling crisis in ABWR type reactor, application of computer codes RELAP/SCDAPSIM and ASTEC for modelling of severe accident in spent nuclear fuel pools, and application of computer codes RELAP5, ASTEC and COCOSYS for modelling of cooling of internal structures in cooling circuits and vacuum (plasma) vessels of fusion facilities are discussed. Analysis of fusion facilities were not limited to thermal-hydraulics only and there were performed analysis of structural material activation and the investigation of decay heat characteristics and the contact dose rate was determined. These parameters are determined for the materials (ferritic martensitic steel EUROFER, copper alloy CoCrZr and steel SS316L(N)-IG) that are planned to be used for the blanket and divertor. In 2016, the research of hydrogen mixing and combustion in nuclear power plant containments was continued, the uncertainty and sensitivity analysis of hydrogen combustion was performed. At the same time, the research of aerosol and radioactive nuclide transfer and deposition in the reactor cooling circuit and containment was conducted. Based on the experience accumulated during the entire period of the Long-term institutional R&D program and considering the developed simulation models in 2016 there was performed integrated investigation of PHEBUS FPT-1 test covering processes starting from overheating and melting of nuclear fuel, transport of radionuclides and chemical transformations in the cooling circuit, and finishing with aerosols’ deposition in containment. Performed investigations revealed that the numerical models of physical and, particularly, chemical processes need to be improved. In the field of strength analysis the structural integrity analysis methodology of the main cooling circuit of generation IV nuclear reactors was prepared, and modelling of fusion facility W7-X pipeline using finite element methods was continued. Also a methodology was prepared, which enables to solve a complex task of reinforced constructions’ structural integrity in case of airplane crash. In the field of material science, research of dependence of welding seams’ mechanical characteristics on fatigue and porosity of seams was investigated. The obtained results revealed that connection of welding would become more stable under bigger deformation values if thermal treatment time would be optimized taking into account the size of remaining strains. 

All the above-mentioned works and numerical studies were combined and used to develop an umbrella complex (deterministic and probabilistic) safety analysis methodology.

During implementation of the program, the research was carried out and experience accumulated, important for improving the competence of Lithuanian researchers working in the field of nuclear energy, which is necessary seeking to estimate safety of nuclear power plants constructed or to be constructed both in Lithuania and neighbouring countries during all NPP lifetime stages: selection of NPP, design, construction, operation, its shutdown and management of radioactive waste. Participation in design and analysis activities of nuclear fusion facilities will enable the Laboratory to keep up with the most up-to-date technologies and retain a high-level scientific potential.


   STATE FUNDED RESEARCH

In 2016, a new three-year work Expansion of best-estimate method for research of heat and neutron transfer processes was launched. In this state funded work it is planned to continue with earlier initiated research and to analyse other aspects of best-estimate method application.  Activities are carried out in five working groups, which are united by best-estimate method application:
  • Analysis of accidents in BWR, ABWR reactors, covering severe accidents as well;
  • Analysis of accidents in spent nuclear fuel pools;
  • Analysis of accident processes in containments of nuclear and thermal-nuclear facilities;
  • Numerical modelling or processes in main heat supply network;
  • Numerical modelling of materials activation processes.
During the first working year, application of best-estimate method while modelling boiling crisis in BWR and ABWR reactors was revealed, and activities were initiated related with modelling  electricity complete loss analysis in ABWR reactor. Results of beyond-design accidents modelling in nuclear devices (particularly in spent nuclear fuel pools) are distinguished for very big uncertainties. Identification of the impact of calculation results uncertainties’ limits and uncertainty parameters on the results as well as recommendations for improving numerical models and numerical methods will be a new target activity in this field. In 2016, a BWR reactor spent fuel pool model was developed, the first analysis results of water discharge from the pool were obtained. The uncertainties and sensitivity analysis while conducting research of processes occurring in nuclear facilities will enable to tune up the models of distribution and transfer of hydrogen and radioactive isotopes in precipitation compartments and to estimate the uncertainties of calculation results. Conducted research revealed that uncertainties arising due to various parameter uncertainties in numerical model are similar to the uncertainties arising due to “user effect” (researcher’s freedom to choose physical and other models) and due to choice of software codes. Besides, after conducting research basic parameters were identified, that have the biggest impact on thermal-hydraulic parameters and hydrogen arrangement in the compartments of protective cask. Application of uncertainties and sensitivity analysis while performing analysis of city’s main heat supply network development is a new step in the application of best estimate method. The method would be applied for calibration of models as well as estimation of the analysis accuracy or for preparing recommendations for improvement of numerical models. During the first working years numerical hydraulic models of Kaunas and Utena cities were prepared and they were verified by comparing measured and calculated parameters of known hydraulic regimes. Then the primary flow analysis under different network loads was carried out. The uncertainties and sensitivity analysis has never been preformed in activation processes research of thermal-nuclear equipment construction materials. In 2016, radiation scenarios for thermal-nuclear devices divertor were analysed by emphasizing activation of cooling system functional materials and heat-carrier. Sensitivity and uncertainty analysis is to be performed for numerical research results.

Water flows distribution analysis in Kaunas city district heating network, standard heating season regime
Water flows distribution analysis in Kaunas city district heating network, standard heating season regime

In 2016, the implementation of research work Risk assessment of critical infrastructures, financed by the budget subsidies, was continued. Infrastructure assessment at a critical object is a constituent part of any state’s national safety. EU members are obliged to conduct risk assessment and ensure protection of critical infrastructure objects based on EC published green book European program on CI object protection and later adopted European Council Directive 2008/114/EC On the identification and designation of European Critical Infrastructures and the assessment of the need to improve their protection. Methodology of risk assessment of critical infrastructures, covering identification of hazards, assessment of critical infrastructure elements and probability of element functioning, was developed.

In 2016, budget-funded work Study of turbulence self excitation in the condensed two-phase flow was continued. For analysis of water flow transition from laminar to turbulent dependence on vapour velocity flowing over it, a graphic analysis of temperature field dynamics was applied. With this method after visualizing the turbulence it was determined that even though Re criteria identifies laminar flow, however, a factual water flow regime may be turbulent.

Different intensity of turbulence generated by interphase interaction
Different intensity of turbulence generated by interphase interaction

In order to facilitate the interpretation of measurement results of temperature and velocity fields, two-phase flow model was further developed using ANSYS CFX computational hydrodynamics code. Separate two-phase velocity and temperature fields, and momentum transfer through the interphase surface were simulated. The development of the model aims to incorporate heat and mass transfer between phases.



2. HIGHEST LEVEL SCIENTIFIC RESEARCH FINANCED BY THE EUROPEAN COMMISSION

    EU PROGRAMME FOR RESEARCH AND INNOVATION HORIZON 2020

  Scientific research of nuclear fusion


In 2016, during implementation of EUROfusion project, researchers of the Institute were in charge of coordination and execution of several tasks. The project activity involved PhD students and young scientists. LEI contributes the most to works in WPSAE work package, devoted for safety assessment of nuclear fusion reactors. While implementing the work plan, the overview of computer codes for estimation of fusion facilities, was carried out as well as numerical investigation of one of the chosen accident scenarios. Numerical model for deterministic assessment of another accident scenario was initiated, together with partners from CIEMAT (Spain) the uncertainty assessment methodology was being prepared, also DEMO activation analysis was carried out.

The activation, nuclear decay heat and radiation dose rate are important parameters describing nuclear processes. In 2016, activation and decay heat calculations were carried out for DEMO Water Cooled Lithium-Lead (WCLL) blanket. Activation calculations were performed using a coupled transport and activation codes MCNP/FISPACT. In 2016, LEI got engaged in the activities of another work package (ENS – Early Neutron Source), which include neutron and activation analysis of the planned neutron source. It is planned that this source will be used to irradiate nuclear fusion reactor construction materials by 14 MeV neutrons.

In 2016, the laboratory further continued to participate in the campaigns related with the experiments implemented in the largest in Europe operated nuclear fusion reactor, Joint European Thorus (JET). LEI along with other partners analyses data by carrying out tomographic analysis of the analogous bolometer device signal by drafting a plasma power map in a tokamak vacuum vessel.

Plasma power distribution in JET tokomak vacuum vessel
Plasma power distribution in JET tokamak vacuum vessel


Scientific research of nuclear safety

  Baltic Region Initiative for Long Lasting InnovAtive Nuclear Technologies


In 2016, a joint Polish, Lithuanian, Latvian and Swedish organizations programme Horizon 2020 EURATOM project BRILLIANT was continued. The objective of the project is to determine the actual obstacles faced by nuclear energy development and try to overcome them. Universities, research institutes and a business partner JSC VAE SPB participate in the project, the aim of which is to prepare for the construction of Visaginas NPP in Lithuania. During the year 2016 project ideas and activities were presented for the interested institutions of Poland, Latvia and Estonia, in September, an introductory visit to Oskarshamn NPP, operated in Sweden, took place. During this visit, including representatives from Lithuanian Ministry of Foreign Affairs, the participants got acquainted with Swedish experience, also had a possibility to see how to successfully operate nuclear power plants and manage the radioactive waste, were introduced to present nuclear energy infrastructure. Oskarshamn is a good example on how organizations operating nuclear energy infrastructure and local residents can successfully cooperate.


  In-Vessel Melt Retention Severe Accident Management Strategy for Existing and Future NPPs

The activity of EU research and innovation program Horizon 2020 project IVMR has been officially launched in June 2015. In this four-year project, LEI participates together with 23 partner institutions from 14 European countries. Retention (stabilization) of the melted core in the nuclear reactor housing is recognized as a very important measure in order to stabilize the situation in the nuclear power plant in the case of severe accident. This measure reduces the amount of generated hydrogen, allows avoiding melt reaction with concrete and is very effective measure in reducing failure risk of the reactor containment. This measure has already been implemented in several VVER-type nuclear reactors and is included in some new nuclear power plant designs. The objective of the IVMR project is to evaluate the expediency of application of this measure to various operating and planned to build nuclear power plants in the European Union. In this project, researchers of the Laboratory of Nuclear Installation Safety participate in project work group for reactor modelling and IVMR strategy application to accident management. Together with experts from KTH (Sweden), GRS (Germany) and HZDR (Germany), it is foreseen to simulate severe accidents in BWR by applying numeric methods. In 2016, LEI specialists applying RELAP/SCDAPSIM Mod3.4 package developed a numerical model of the second generation boiling water reactor BWR-5 to simulate thermal-hydraulic processes.

The accident due to large leak from the reactor cooling circuit and loss of power supply at the same time was modelled. As the consequence of such accident the core melt and the collapse of melt into the lower part of the reactor vessel is expected. The collapsed melt may heat up the lower part of reactor vessel. In this case was simulated the flooding of lower structural part of the vessel from outside by water and the possibility to cooldown the reactor vessel, protecting it from damage, was evaluated. In this way, the impact of IVMR strategy will be assessed.

RELAP/SCDAPSIM model of the lower part of BWR-5 reactor vessel, which is cooled form outside by water
RELAP/SCDAPSIM model of the lower part of BWR-5 reactor vessel, which is cooled form outside by water


  FAST Nuclear Emergency Tools

The activity of Horizon 2020 programme project FASTNET has been launched in October 2015. The objective of the project is to develop a methodology that would cover the assessment of release of fission products and emergency preparedness planning issues in case of an accident. All types of nuclear power plants operated or planned to be operated in Europe, such as pressurized water reactors PWR, EPR and VVER, boiling water reactors BWR, heavy water reactors CANDU and others will be investigated under this project. Moreover, possible release of fission products in case of an accident at the spent nuclear fuel pool will be considered. First, database of accident scenarios will be compiled, which will also include the assessment of possible release of fission products. This database will be compiled based on deterministic and probabilistic safety analysis results, which will be carried out by the organizations participating in the project. Later, also harmonized methods will be developed that will allow performing a fast prediction of the fission products release into the environment. The obtained results would help the responsible institutions in each country to have a tool, enabling to perform a fast prediction of the course of the emergency and to make necessary decisions notwithstanding in which world’s nuclear power plant the event took place. Moreover, the developed prediction tool will not only cover the events related to the nuclear reactor, but also the events in the spent fuel pools.

In 2016, several project meetings took place during which general project implementation issues were discussed as well as development of accident scenario data base. A preliminary list for accident scenarios was developed and a conception of future data base was discussed.


  INcreasing Safety in NPPs by Covering gaps in Environmental Fatigue Assessment

In 2016, EU programme Horizon 2020 project INCEFA-Plus was continued (the beginning 2015). Main objective of the project – to conduct fatigue damage research under reactor operation environment conditions to ensure safe operation of European nuclear power plants. LEI Laboratories of Material Research and Testing and Nuclear Installation Safety participate in it. Regulatory documents and references related to fatigue research were studied in 2016; in accordance with regulatory documents and  the fatigue test matrix as submitted by the coordinator of the 2nd working package (Test programme), LEI project fatigue test programme was prepared and coordinated. In September 4 samples of 304L steel were received for fatigue research. The experimental tests of fatigue will be carried out in 2017 at the laboratory of Materials research and testing. At the present moment 304 steel samples are being manufactured for pilot test and preparation of the facility for testing according project test matrix.


REEEM project logo  Role of technologies in an energy efficient economy – model-based analysis of policy measures and transformation pathways to a sustainable energy system  EU logo

In 2016, EU Research and Innovation programme Horizon 2020 project REEEM was launched. This a 42 month duration project, where 11 institutions from 9 European countries participate, including 2 LEI laboratories. The project is being coordinated by Swedish KTH Royal Institute of Technology.

REEEM aims to gain a clear and comprehensive understanding of the system-wide implications of energy strategies in support of transitions to a competitive low-carbon EU energy society, given the objectives and framework outlined in the Strategic Energy Technology Plan (SET-Plan). The provisions of the energy services in this society will be defined by their sustainability, affordability, efficiency, energy security and reliability.

Main objectives of the project is to develop an integrated assessment framework, to define pathways towards a low-carbon society and assess their potential implications by performing case studies for different European regions, to bridge the science-policy gap through a clear communication using decision support tools and to ensure transparency in the process.

The project is comprised of 7 core work packages  and supporting work package on project management, and covers the following issues: transformation strategies and pathways of energy system, development of energy technology and innovation, the economic impacts of energy development, society, consumers and behaviour, environment, health and resources, energy systems integration, stakeholder engagement and dissemination.

Laboratory researchers in this project mainly participate in the tasks related with formulation of pathways and pathway clusters, case studies on district heating and energy security. Main contribution of the laboratory researchers – development of the case study for assessment of regional energy security of the Baltic region and Finland within different scenarios by applying modelling techniques.

In 2016, the project kick-off meeting took place during which project participants along with EC representatives discussed work plans and project implementation issues.  On April and November of 2016, the project General Assemblies (workshops) took place, where project participants shared their experience, reviewed the progress of project implementation and discussed future activities.




EU 7th FRAMEWORK SCIENTIFIC RESEARCH, TECHNOLOGICAL DEVELOPMENT AND DEMONSTRATIONAL ACTIVITY PROGRAM



  Establishment of ASTEC software code as a means for management of severe accidents in Europe

EU FP7 programme project CESAM (Code for European Severe Accident Management) has been launched on April 1, 2013. Project objective is to establish ASTEC software code as a main mean for management of severe accidents in all II and III generation NPPs in Europe (PWR, BWR, CANDU). 18 institutions from EU states participate in the project. LEI researchers participate in EC Joint Research Center (JRC) coordinated work package Plant Applications and Severe Accident Management. Using ASTEC code, during the project, LEI together with partners will create a model of a nuclear power plant with GE BWR4-Mark I type reactor and will carry out comparative calculations of spent fuel pools at the chosen BWR type power plant using ASTEC and RELAP/SCDAPSIM codes.

In 2016, the creators of the software package submitted several updated versions of ASTEC code, therefore Laboratory specialists modified the earlier developed GE BWR4-Mark I type power plant model, taking into account the updates in ASTEC V2.1.0.5 version. Also the Laboratory researchers updated the earlier created BWR type spent fuel pool model. Using the improved GE BWR4-Mark I type power plant spent fuel pool model the water loss calculations were carried out, which were compared with the results obtained using RELAP/SCDAPSIM code.

Structure of ASTEC integral code
Structure of ASTEC integral code

Spent fuel pool behaviour in loss of cooling or loss of coolant accidents

EU FP7 programme project NUGENIA-PLUS, AIR-SFP “Preparing NUGENIA for H2020: Spent fuel pool behaviour in loss of cooling or loss of coolant accidents” has been launched on March 1, 2015. Project duration was 18 months. Project is managed by IRSN (France); 14 organizations from EU countries participate in it.

Benchmark calculations of heat removal disruptions and loss of coolant in Fukushima Daichi NPP Unit 4 spent fuel pool were conducted. These calculations were performed using ASTEC V2.1.0.5 and RELAP5 and RELAP/SCDAPSIM codes. After performing these calculations, the system criticality was assessed by analysing situations that might cause power increase. The laboratory specialists developed a numerical model using SCALE 6.1.3 code KENO-VI module. A 3D model of a spent fuel rack system in a spent fuel pool was developed, and criticality dependence from water density was investigated. Additionally, the effect of distance (pitch) between rack cells on criticality was investigated as well After conducting the benchmark calculations, a roadmap for further research and development on SFP accidents was prepared.

3D model of rack cell system with fuel assemblies for SCALE 6.1.3 code
3D model of rack cell system with fuel assemblies for SCALE 6.1.3 code


Justification of Risk Reduction through In-Service Inspection

A REDUCE part Justification of risk reduction by applying operational control of NUGENIA-PLUS project (preparing NUGENIA for H2020) of EU FP7 programme  with additional funding from the Agency for Science, Innovation and Technology, has been launched in the second part of 2015, the activities were continued in 2016. As it was planned, there were participation:
  • at the meetings of the project REDUCE part and at the meetings related to project activities and NUGENIA-PLUS;
  • in preparation of the report on benchmark calculations (including risk assessment);
  • in the preparation of guidelines for risk reduction applying inspection.
Various parameters of boiling water reactor (BWR) and pressurized water reactor (PWR) pipeline welds were chosen for research (in total 14 main cases, among which cracks resulting from the impact of intergranular corrosion and failure were considered).

In scope of the fourth work package (coordinated by LEI), the manual (guideline) of risk reduction assessment based on operational control, i.e. Guideline for assessment of risk reduction achieved by ISI was prepared. This guideline was prepared in accordance with the results obtained in other work packages and NUGENIA/ENIQ methodological document European Framework Document for Risk-Informed In-Service Inspection.
The project participants basic highlight of the activities was oriented towards the application of risk based inspection of not only pipeline but also other systems and components of nuclear objects. Participation in NUGENIA initiated projects and individual technical meetings as well as NUGENIA- PLUS project meetings enabled to be better engaged in safety research perspectives of nuclear power plants and provided possibilities to be involved in new scientific and applied works in the field of nuclear energy safety analysis and reliability assessment. Experience gained while implementing this project could be also applied in the activities not related to nuclear power plants.


  Advanced Safety Assessment Methodologies: Extended PSA

Since 2013, LEI participates in the Consortium, managed by the Institut de Radioprotection et de Sûreté Nucléaire (IRSN), by implementing new EU FP7 programme project Advanced Safety Assessment Methodology: Extended PSA. The project activity began on July 1, 2013; the duration of the project is 36 months. 28 organizations from 18 European countries are partners of the project; several associate members from the USA and Japan also take part in the project: US-NRC, JANSI, and TEPCO. EC confirmed that the project is continued till year 2017.

The project particularly focuses on probabilistic safety analysis of various extreme external hazards (meteorological, human induced and other events). LEI specialists most significantly contributed in developing methodologies of external events selection and their analysis, sharing the available research experience, publications and updating/supplementing the project reports. 24 reports were prepared by the final seminar of the project in September, major part of which is public. In 2016, a great deal of attention was further devoted to the analysis of various extreme external hazards (meteorological, human induced and other events), whereas in working meetings took place a detailed discussion of various reports from separate project work packages:
  • WP10: Relationship with End-Users;
  • WP21: Initiating events (internal and external hazards) modelling;
  • WP22: How to introduce hazards in L1 PSA and all possibilities of events combination?
  • WP30: General issues regarding extended PSA scope and applications;
  • WP40: 2 Specific issues related to L2 PSA
Laboratory researchers, by participating in the activities of all project work packages, in 2016 mostly focused on the activities related to identification and analysis of the initial events (internal and external hazards). Besides, a lot of attention was given to the needs of End-Users while conducting analyses of safety and with it related reports/methodologies. The largest contribution of LEI is to WP21/WP22 work packages. In them, LEI coordinated preparation of the report related to meteorological hazards and their impact (emphasizing extreme winds, including tornadoes, extreme temperatures and snow covering hazards).
Earlier in the corresponding work package the material for Link between external initiating events of PSA and NPP design basis conditions was presented.

Participation in such international projects as ASAMPSA_E allowed immediate access to the latest ideas on risk assessment and probabilistic analysis performance and application, also allowed contributing to new theoretical and applied research in the field of safety analysis. Future plans are to actively develop bilateral cooperation with ASAMPSA_E project participants.


Assessment of Regional CApabilities for new reactors Development through an Integrated Approach

In 2016, the works of EU FP7 ARCADIA project were completed. This project covered two nuclear energy implementation areas foreseen in the Strategic research and innovation plan of SNETP technological platform:

1) ESNII through support of construction of Generation IV liquid lead-cooled nuclear fast reactor in Romania, and

2) NUGENIA through support in dealing with the remaining safety issues of Generation III nuclear reactors.

The final Project event (conference) took place in September 2016, in Pitesti (Romania). A number of Romanian science, business and politics representatives participated in the conference. Local society is waiting for ALFRED reactor project to be launched since they see good perspectives for science innovations.




3. SCIENTIFIC RESEARCH CARRIED OUT FOLLOWING AGREEMENTS WITH EU AND LITHUANIAN ECONOMIC SUBJECTS

  Modifications or replacement of auxiliary maintenance systems for spent nuclear fuel casks at Ignalina NPP spent fuel pool halls

In 2016, works under the contract with GNS (Gesselshaft für Nuklear-Service mbH, Germany) Modification or replacement of auxiliary maintenance systems for spent nuclear fuel casks at Ignalina NPP spent fuel pool halls were continued. The work is performed under cooperation with SC TECOS and machinery plant SC ASTRA. During implementation of the project it is planned to manufacture and install six absorbers at the INPP fuel storage pool halls (three different absorbers at each Ignalina NPP Unit) and other equipment for maintenance of spent nuclear fuel casks. The designation of the main components of this equipment, i.e. absorbers, is to absorb energy in case of accidental drop of casks loaded with spent nuclear fuel or an earthquake, and ensure that the loads on the building and cask structures will not exceed the permitted limits. Warranty works, as foreseen in the agreement, were continued in 2016.

Absorbers in the spent nuclear fuel pool at Ignalina NPP Unit 1
Absorbers in the spent nuclear fuel pool at Ignalina NPP Unit 1


Support for Iraq’s nuclear energy regulator upon implementing disposal of radioactive materials, decommissioning of nuclear objects and handling of contaminated sites

In 2016, agreement was signed with French State Enterprise Radioactive Waste Management Agency, during which implementation is foreseen to contribute by providing support to Iraq’s nuclear energy regulator by conducting radioactive materials disposal, decommissioning of nuclear objects as well as handling of contaminated sites.
During the project the activities are divided into the following tasks:

1. to review regulatory documents, which are in force at the moment in Iraq, regulating radioactive waste disposal, decommissioning of nuclear objects and handling of contaminated environment;
2. to compare the existing regulatory documents with international standards and best EU applicable practice;
3. to prepare recommendations for improvement of existing regulatory documents;
4. to prepare security manuals/recommendations for specific fields;
5. to prepare recommendations for the assessment of radioactive repositories’ projects;
6. to review and estimate Contractor’s submitted safety reports related with design of new landfill repository;
7. to transfer gained experience in the field of radioactive waste repositories’ surveillance;
8. to prepare material and organize trainings for Contractor’s personnel in the field of radioactive waste disposal, decommissioning of nuclear objects and environment handling.

Laboratory researchers participate in all the above stated tasks. In 2016, regulatory documents existing in Iraq were reviewed, the comparison with international standards and best practice in EU countries  was carried out.


  Valid safety reports and internal emergency plans of AB “Klaipedos nafta“ oil terminal and liquefied natural gas terminal updating and approval services purchasing

In 2016, agreement was signed with The Coastal Research and Planning Institute regarding updating and adjustment of valid AB „Klaipedos nafta“ documents. During the project it is foreseen to perform update of oil terminal and liquefied natural gas terminal safety reports and internal emergency plans, including quantitative assessment of processes evoked risks. The objective of this updating covers:
  1. Quantitative assessment of planned to be used and store chemical materials, their amounts and technological processes, working measures, processes evoked risk, update and approval of safety report with the competent institution;  
  2. Integrated quantitative risk assessment for current oil terminal economy activities and future economy activities, by identifying probable accident/incident scenarios, taking into account frequency and consequences of these incidents, social risk evoked by incidents (submitting data in F-N curve) and individual risk (risk contour mapping).
Updating of oil terminal safety report and internal emergency plan will evaluate development plans of planned oil terminal economy activity, i.e. development of light oil products park and optimization of liquid fuel mixtures management, introducing new heavy fuel oil storages, oil products’ unload trestles, construction and operation of railway loop and new oil products storage tanks, stage II of light oil products’ park development, construction and operation of liquefied natural gas distribution station. Updating of safety report and internal emergency plan of liquefied natural gas terminal is carried out after taking into account planned reload of liquefied natural gas from Floating storage and regasification unit to gas carriers.


Safety assessment of Maisiagala radioactive waste storage facility

In 2016, in cooperation with the Institute of Physics of the Center for Physical and Technological Sciences, the Periodical Safety Assessment Report for Maisiagala radioactive waste storage facility was prepared. The changes of legal regulations, the storage facility site and environmental conditions, aging of structures, systems and components and other factors that may influence the safety of the storage facility were considered. During implementation of the project one of the physical barrier (geomembrane) used for storage facility containment was excavated. It was buried in the past nearby storage facility with the objective later to be tested whether its properties haven’t degraded. Geomembrane was installed during reconstruction of the storage facility containment in 2006, its purpose – to limit water entrance into storage facility. Physical and mechanical properties of geomembrane were investigated at LEI laboratories. Testing results confirmed that geomembrane properties had not changed. Scenarios for radionuclide migration through soil were simulated using RESRAD-OFFSITE numerical model, whereas scenarios of radionuclides transfer through air were estimated also. The long-term radionuclides analysis results confirmed that the storage facility does not meet the requirements for such type of repository and in the nearest future it is planned all radioactive materials from the repository to transfer to the disposal facilities present nearby Ignalina NPP.

 
Maisiagala radioactive waste storage facility


Continue to Part 2 of laboratory description >>>

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4. Transfer of knowledge on Nuclear Safety and training organization
5. Participation in EU research organizations and competence networks
6. Training of scientists and publication of scientific results

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