Monitoring Liquid Radioactive Waste Discharges Released from Nuclear Power Plant

2014 ◽  
Vol 1059 ◽  
pp. 83-90 ◽  
Author(s):  
Marián Bujna ◽  
Miroslav Prístavka ◽  
Maroš Korenko ◽  
Petr Dostál
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Radioactive Waste ◽  
Nuclear Power ◽  
Power Plants ◽  
Negative Impact ◽  
Liquid Radioactive Waste ◽  
Nuclear Industry ◽  
Protective Measures ◽  
The Impact

The purpose of this paper is to monitor the amount of discharged radioactive liquid discharges from nuclear power plant and propose ways to reduce the amount given. The report consists of a literature review, objective and methodology proposed. The methodology and results consist of distribution of waste, originally liquid radioactive waste (LRW), a source of LRW, a year-round monitoring of liquid effluents of nuclear power plant and eventual adoption of protective measures. Tritium, as one of the LRW, is a radioactive substance having a negative impact on the environment. In the course of our research, we have found an increased dose of tritium over permitted annual limit. We investigated the impact of tritium on the environment and took protective measures to reduce the amount of tritium released in the environment. The report may serve as a basis for other nuclear power plants and the entire nuclear industry.

scholarly journals Comparison and Evaluation of Domestic and Foreign Radiation Environmental Standards for Nuclear Power Plants

2021 ◽  
Vol 2083 (2) ◽  
pp. 022020
Author(s):  
Jiahuan Yu ◽  
Xiaofeng Zhang
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
The United States ◽  
Discharge System ◽  
Radioactive Effluent ◽  
Effluent Discharge ◽  
The Impact

Abstract With the development of the nuclear energy industry and the increasing demand for environmental protection, the impact of nuclear power plant radiation on the environment has gradually entered the public view. This article combs the nuclear power plant radiation environmental management systems of several countries, takes the domestic and foreign management of radioactive effluent discharge from nuclear power plants as a starting point, analyses and compares the laws and standards related to radioactive effluents from nuclear power plants in France, the United States, China, and South Korea. In this paper, the management improvement of radioactive effluent discharge system of Chinese nuclear power plants has been discussed.

Root Cause of Thermal Sleeve Loosening in a Korean Standard Nuclear Power Plant

2006 ◽  
Author(s):  
Sang-Nyung Kim ◽  
Sang-Gyu Lim
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Measurement Data ◽  
Significant Loss ◽  
Design Modification ◽  
Root Cause ◽  
Explosive Expansion ◽  
The Impact

The safety injection (SI) nozzle of a 1000MWe-class Korean standard nuclear power plant (KSNP) is fitted with thermal sleeves (T/S) to alleviate thermal fatigue. Thermal sleeves in KSNP #3 & #4 in Yeonggwang (YG) & Ulchin (UC) are manufactured out of In-600 and fitted solidly without any problem, whereas KSNP #5 & #6 in the same nuclear power plants, also fitted with thermal sleeves made of In-690 for increased corrosion resistance, experienced a loosening of thermal sleeves in all reactors except KSNP YG #5-1A, resulting in significant loss of generation availability. An investigation into the cause of the loosening of the thermal sleeves only found out that the thermal sleeves were subject to severe vibration and rotation, failing to uncover the root cause and mechanism of the loosening. In an effort to identify the root cause of T/S loosening, three suspected causes were analyzed: (1) the impact force of flow on the T/S when the safety SI nozzle was in operation, (2) the differences between In-600 and In-690 in terms of physical and chemical properties (notably the thermal expansion coefficient), and (3) the positioning error after explosive expansion of the T/S as well as the asymmetric expansion of T/S. It was confirmed that none of the three suspected causes could be considered as the root cause. However, after reviewing design changes applied to the Palo Verde nuclear plant predating KSNP YG #3 & #4 to KSNP #5 & #6, it was realized that the second design modification (in terms of groove depth & material) had required an additional explosive energy by 150% in aggregate, but the amount of gunpowder and the explosive expansion method were the same as before, resulting in insufficient explosive force that led to poor thermal sleeve expansion. T/S measurement data and rubbing copies also support this conclusion. In addition, it is our judgment that the acceptance criteria applicable to T/S fitting was not strict enough, failing to single out thermal sleeves that were not expanded sufficiently. Furthermore, the T/S loosening was also attributable to lenient quality control before and after fitting the T/S that resulted in significant uncertainty. Lastly, in a flow-induced vibration test planned to account for the flow mechanism that had a direct impact upon the loosening of the thermal sleeves that were not fitted completely, it was discovered that the T/S loosening was attributable to RCS main flow. In addition, it was proven theoretically that the rotation of the T/S was induced by vibration.

scholarly journals Blowout Accident Impact Analysis Method for the Siting of Offshore Floating Nuclear Power Plant in Offshore Oil Fields

2019 ◽  
Vol 2019 ◽  
pp. 1-7
Author(s):  
Zhigang Lan
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Impact Analysis ◽  
Oil Spills ◽  
Oil Field ◽  
Oil Fields ◽  
Offshore Oil ◽  
The Impact

Focused on the utilization of nuclear energy in offshore oil fields, the correspondence between various hazards caused by blowout accidents (including associated, secondary, and derivative hazards) and the initiating events that may lead to accidents of offshore floating nuclear power plant (OFNPP) is established. The risk source, risk characteristics, risk evolution, and risk action mode of blowout accidents in offshore oil fields are summarized and analyzed. The impacts of blowout accident in offshore oil field on OFNPP are comprehensively analyzed, including injection combustion and spilled oil combustion induced by well blowout, drifting and explosion of deflagration vapor clouds formed by well blowouts, seawater pollution caused by blowout oil spills, the toxic gas cloud caused by well blowout, and the impact of mobile fire source formed by a burning oil spill on OFNPP at sea. The preliminary analysis methods and corresponding procedures are established for the impact of blowout accidents on offshore floating nuclear power plants in offshore oil fields, and a calculation example is given in order to further illustrate the methods.

EDF Decommissioning Programme: A Global Commitment to a Sustainable Development

2003 ◽  
Author(s):  
Jean-Jacques Grenouillet
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Energy ◽  
Cost Effective ◽  
Eu Enlargement ◽  
Nuclear Industry ◽  
Successful Implementation ◽  
Early Closure

Nowadays, decommissioning of nuclear power plants has become a key issue for nuclear industry in Europe. The phasing out of nuclear energy in Germany, Belgium and Sweden, as well as the early closure of nuclear units in applicant countries in the frame of EU enlargement, has largely contributed to consider decommissioning as the next challenge to face. The situation is slightly different in France where nuclear energy is still considered as a safe, cost-effective and environment friendly energy source. Electricite´ de France (EDF) is working on the development of a new generation of reactor to replace the existing one and erection of a new nuclear power plant could start in the next few years. Nevertheless, to achieve this objective, it will be necessary to get the support of political decision-makers and the acceptance of public opinion. Due to the growing concern of these stakeholders for environmental issues, their support can only be obtained if it is possible to demonstrate that nuclear energy industry will not leave behind unsolved issues that will be a burden to the next generations. In this context decommissioning of the first generation of EDF NPPs constitutes a prerequisite for the erection of a new type of nuclear power plant. This paper will present the programme defined by EDF for the decommissioning of its nine already shutdown reactors (Fig. 1). The reasons of the recent evolution of EDF decommissioning strategy will be explained and the key issues that will contribute to the successful implementation of this programme will be addressed. Finally, what has been achieved on sites so far and major planned activities will be described.

Problems of Radioactive Waste Management at Chornobyl Nuclear Power Plant (ChNPP)

2003 ◽  
Author(s):  
Borys Ya. Oskolkov ◽  
Yuri A. Neretin ◽  
Valeryi P. Saliy ◽  
Valeryi A. Seyda ◽  
Vyascheslav V. Fomin
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Radioactive Waste ◽  
Nuclear Power ◽  
Wide Spectrum ◽  
Liquid Radioactive Waste ◽  
Chemical Properties ◽  
Building Structures ◽  
Exclusion Zone ◽  
Management Problems

According to the assessments the overall amount of radioactive waste (RAW) to be reprocessed and buried at the Chornobyl NPP site amounts to 1,696,738 m3 (without regard for reactor metal structures, dismantling of building structures and plan constructions, and the Unit Shelter building). The overall activity of radioactive waste are evaluated at 1,640,504.64 ΤBq. The RAW management activities are implemented at the Chornoby1 NPP within the frame of several programs of different hierarchy including the State Comprehensive Program for RAW Management in Ukraine, Integrated Program of RAW Management at the Chornoby1 NPP Shutdown Stage and Transformation of the Unit Shelter into an Ecologically Safe System. At the present time a number of key RAW management facilities are being constructed within the frame of the international aid to Ukraine. They are the Liquid Radioactive Waste Plant and Solid Radioactive Waste Reprocessing Complex. As of now, the issues concerning RAW utilization at the Unit Shelter are resolved at a conceptual level. There has not practical decision in relation to a geologic facility. The complexity and scale of ChNPP RAW management problems will require significant efforts of both Ukraine and the whole world community to solve these issues. The task related to removal and final burial of accumulated and generating radioactive waste is one of the main aspects of decommissioning activities at any nuclear power plant. RAW management work is the most important and complicated work performed at the Chornoby1 NPP. The specific features of ChNPP RAW management are as follows: • Variety of RAW generation sources, their types, physical and chemical properties. • Large amount of radioactive wastes which already exist and those generated in the decommissioning process. • Presence of disorganized RAW characterized by wide spatial distribution within the Unit Shelter and at the plant site. • Need to apply a very wide spectrum of various RAW management techniques depending on their location and type. • Need in developing unique techniques to manage special types of RAW located at the site (fuel containing masses of the Unit Shelter). • Large amount and variety of facilities required for RAW final storage. • Absence of reliable and serviceable instrumental procedures and necessary equipment to define RAW properties for RAW separation and classification. • Ecological peculiarities of RAW management within the Chornoby1 zone. • Multiphase decontamination and restoration processes resulting in RAW formation. • Need in integrating RAW management problems at the ChNPP and within the Chornoby1 Exclusion Zone taken as whole. • Long time period required for implementing the whole program of RAW management at the ChNPP. • Large quantity of people involved in RAW management process (local and foreign participants, different organization operated by various departments).

Grid-Connected Nuclear Power Plant Key Issues Summary

2014 ◽  
Vol 521 ◽  
pp. 530-535
Author(s):  
Meng Wang ◽  
Jian Ding ◽  
Tian Tang ◽  
Zhang Sui Lin ◽  
Zhen Da Hu ◽  
...  
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Large Scale ◽  
Power Modeling ◽  
Modeling Simulation ◽  
Load Following ◽  
Key Issues ◽  
The Impact

The current situation of nuclear power plants at home and abroad is described, and the impact of large-scale nuclear power accessing to the grid is analyzed, specifically in the aspects of nuclear power modeling, simulation, load following, reliability, fault diagnosis, etc. Nuclear power accessing to the grid will bring a series of problems, the causes of each problem, the main solutions and future development directions are summarized.

Analysis and Evaluation of the Setting Value Drift of SEBIM Relief Valve Used in Nuclear Power Plant

2013 ◽  
Author(s):  
Xiaochuan Yang ◽  
Chunlei Luo ◽  
Meng Qu ◽  
Rongfa Shen ◽  
Yinhui Che
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Industry ◽  
Relief Valve ◽  
Analysis And Evaluation ◽  
Operation Period ◽  
Pressure Pipeline ◽  
Important System

SEBIM relief valve is mainly used in safety important system of the nuclear power plant to provide the overpressure protection for the pressure vessel and pressure pipeline which related to the nuclear safety. It is probable that the system will lose the overpressure protection function and lead to a major security hidden danger in the nuclear power plant if the relief valve setting value happens drift. So the problem of the SEBIM relief valve setting value drift has becoming the focus of attention of the whole nuclear industry. It is of great significance to study the setting value drift condition of SEBIM relief valve in the practical application. This paper analyzes the structure and operating principle of the SEBIM valve, and studies the main failure mode of the setting value drift of SEBIM relief valve combining with the operating environment of the equipment. And this paper collects the setting value check data of the SEBIM valve used in two domestic nuclear power plants (These two power plants are named NPP A and NPP B in this paper) during its operation period, and carries on the analysis and evaluation.

Study on the Interaction Between Safety-Related and Non Safety-Related Items in the Component Cooling Water System Room of the Qinshan Nuclear Power Plant in the Earthquake Condition

2020 ◽  
Author(s):  
Liang Zhang ◽  
Gang Xu ◽  
Yue Wang ◽  
Li Chen ◽  
Shao Chong Zhou
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Water System ◽  
Cooling Water ◽  
Life Extension ◽  
Main Body ◽  
Cooling Water System ◽  
The Impact

Abstract Safety-related items in nuclear power plants are now generally placed separately from the non-safety-related items, but it was not strictly required before. Therefore, it is very important to study whether the non-safety-related items will affect the safety-related items when they are dropped down in an earthquake situation, which determines the safety of a nuclear power plant and its future life extension applications. This research was based on the cooling water system room with the safety and non-safety related items installed together, as an example to study whether the non-safety-related items such as vent pipes and DN50 fire fighting pipes arranged above will damage the DN300 pipes and valves arranged below when earthquakes occur. For the experiments, the relative positions of objects in the room was reproduced by 1: 1. The pressure-holding performance of the pipe was used as a criterion for the damage. The research results of the experiments show that when the 10-meter-long DN50 pipe was dropped from the position of 8 meters height and the 8-meter-long vent dropped from position of 3.6 meters height, they do not affect the integrity of the DN300 valve and pipe below. After the experiment, pressure drop in two hours for the pipe is less than 0.1%. The main body of the valve does not fail neither. The numerical simulation study also shows that there is no failure phenomenon in the simulation as well. Compared with the test results, the impact acceleration and the vent deformation both have the same trend.

Teaching of Nuclear Power Plant Safety at the National Technical University of Ukraine Within the New Course in Safety Culture

2012 ◽  
Author(s):  
Vasilij V. Begun ◽  
Sergij V. Begun ◽  
Olena O. Kilina
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Safety Culture ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Safety Analysis ◽  
Nuclear Industry ◽  
Educational Course ◽  
And Training

The necessity of safety analysis methods and probable scenarios of accidents teaching in the education of experts for nuclear industry in Ukraine has been realised only after the Chernobyl accident. We developed the content of the first educational course in probabilistic safety analysis in 1995 based on the experience of the countries having developed nuclear power, the USA first of all, and on the training course of the Idaho National Laboratory. After this in 1996 the new course in probabilistic safety analysis of nuclear power plant (NPP) was adopted at our university. The new educational course in safety for students was developed and adopted in 2009 educational year - “Safety culture at nuclear installations of Ukraine”. Education and training in safety culture in higher educational institutions and in the nuclear power plants is a part of the general modern process of maintenance of safety, it is recommended by IAEA standards. The principles of safety culture are taken as a basis of the modern concept of safety of nuclear power plants. This work has received a positive appreciation from the management of departments of safety and training of the personnel of operating organization National Nuclear Energy Generating Company Energoatom (NNEGC Energoatom) and from other leaders of nuclear industry. The content of this educational course was discussed at the international scientific conferences on safety culture in 2008 and 2010, and was preliminary printed in the professional journal «Nuclear and radiation safety». The purposes of education have been defined as a survey, generalizing course on safety of the NPP with an allocation of safety issues on the foreground. Practical questions of the equipment and NPP systems work, their interaction in emergencies and the role of the human-operator are studied. The procedure of failure analysis at NPP is studied. Students analyze equipment work, root and direct causes of incidents. Methods of estimation of safety conditions based on observable operational indicators are studied. Parameters, variables and indicators of safety culture are studied. As a result of gained experience we have come to the conclusion about high advisability of educational courses in safety for students. Specially formed knowledge and education in the field of safety from a student’s bench are the basis of safety culture of the future nuclear industry expert.

scholarly journals Analysis and Performance Evaluation of Casting Inclusions in the Reactor Coolant Pump Casing of Nuclear Power Plant

2021 ◽  
Vol 257 ◽  
pp. 01076
Author(s):  
Xiaohui Luo ◽  
Jie Yang ◽  
Li Song ◽  
Dezhong Xu
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Material Selection ◽  
Design And Technology ◽  
Coolant Pump ◽  
Impact Performance ◽  
The Impact

The casting quality of the coolant pump casing of the nuclear power plant reactor is directly related to the operational reliability and safety of the nuclear main pump, and plays a key role in the integrity of the pressure-bearing boundary of the reactor primary loop. In this paper, aiming at the low impact performance of the sample during the casting process of the main pump casing of a nuclear power plant, through using failure analysis tools like fishbone diagram from multiple dimensions such as material selection, design and technology, melting analysis, pouring process, riser design, and heat treatment process, and combining with metal macro-fracture analysis and micro-electron microscopy scanning methods for cause analysis, finally, it was found that the basic reason for the low impact performance of the pump shell is that the secondary inclusions appear on the fracture of the sample during the solidification of the molten steel. Using test-retest inspection and finite element mechanics simulation analysis, the comprehensive evaluation of the impact performance of the sample was obtain, which provides an effective solution for the analysis and evaluation of casting inclusions in water pumps of nuclear power plants, and also provides an important reference for the structural optimization and equipment research and development of water pump equipment of nuclear power plants.

Sign in / Sign up

Export Citation Format

Share Document