Nuclear Power Plant Fires and Explosions: Part II — Hydrogen Ignition Overview

2017 ◽  
Author(s):  
Robert A. Leishear
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Water Hammer ◽  
Hydrogen Gas ◽  
Direct Result ◽  
Plant Safety ◽  
Hydrogen Ignition ◽  
Fukushima Daiichi

Major accidents that were affected by hydrogen fires and explosions included Chernobyl, Three Mile Island, and Fukushima Daiichi. Smaller piping explosions have occurred at Hamaoka and Brunsbüttel Nuclear Power Plants. An overview of pertinent topics is presented here to compare similarities and differences between these accidents. In particular, a hydrogen ignition mechanism is presented here, where fluid transients, or water hammer, may cause pressures to compress flammable hydrogen gas in reactor systems. As the gas compresses, it heats to temperatures sufficient to cause autoignition, or dieseling. Autoignition then leads to fires or explosions in nuclear power plant systems. To explain this evolving theory on hydrogen ignition during fires and explosions, various nuclear power plant hydrogen accidents require discussion. For example, Chernobyl explosions were unaffected by water hammer, while a Three Mile Island hydrogen fire was a direct result of water hammer following a reactor meltdown, and explosions that followed a meltdown at Fukushima Daiichi occurred during a water hammer event. Other piping damages also occurred during water hammer events. The primary purpose of this paper is to serve as a literature review of past accidents and to provide new insights into those accidents. In short, what is known versus what is unknown is discussed here with respect to the ignition sources of nuclear power plant fires and explosions. How can nuclear power plant safety be assured unless previous fire and explosion causes are understood? Prior to this work, they were not understood.

Explore the Self-Governance on Nuclear Safety Emergency - A Case Study of the 3rd Nuclear Power Plant

2012 ◽  
Vol 260-261 ◽  
pp. 103-106
Author(s):  
Yi Chun Lin ◽  
Yung Nane Yang
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Alternative Energy ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Nuclear Safety ◽  
Security Issue ◽  
Safety Issues ◽  
Plant Safety

The ripples of the tsunami crisis in Japan triggered introspections of nuclear plant safety issues in the worldwide. Many countries have claimed the suspension of nuclear power plants. However, some countries such as Taiwan, under nearly 99% energy is exported, the disasters force government and citizen to face the importance of nuclear safety, especially the neighborhoods nearby the nuclear power plants. We have to face the nuclear safety since there is no other alternative energy presently. The 3rd nuclear power plant located in the south of Taiwan, which has the same geographic features with Fukushima, Japan. Presently, there is no precedent in Taiwan of precaution and rescue team and civil supervised mechanic on nuclear security issue. This paper will review according to transparent information, public participation and cross-organization cooperation to propose the execution and work division principles, including information monitor, educational propagation, hide and evacuation, emergence aid and care, rear and refuge service. The ultimate target is to establish self-governance inside nearby neighborhood to confront nuclear disaster at the critical moment.

Nuclear Power Plant Emergency Preparedness: Results From an Evaluation of Michigan's Potassium Iodide Distribution Program

2012 ◽  
Vol 6 (3) ◽  
pp. 263-269 ◽  
Author(s):  
Laura R. Zwolinski ◽  
Martha Stanbury ◽  
Susan Manente
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Potassium Iodide ◽  
Emergency Preparedness ◽  
Nuclear Power ◽  
Power Plants ◽  
Body Part ◽  
Emergency Planning ◽  
Telephone Surveys ◽  
Fukushima Daiichi

ABSTRACTBackground: In 2009, the Michigan Department of Community Health (MDCH) made potassium iodide (KI), a nonprescription radio-protective drug, available by mailing vouchers redeemable at local pharmacies for KI tablets, at no cost to residents living within 10 miles of Michigan's 3 nuclear power plants (NPPs). MDCH conducted an evaluation of this program to determine Michigan's KI coverage and to assess general emergency preparedness among residents living near the NPPs.Methods: KI coverage was estimated based on redeemed voucher counts and the 2010 Census. Telephone surveys were administered to a random sample (N = 153) of residents living near Michigan's NPPs to evaluate general emergency preparedness, reasons for voucher use or nonuse, and KI knowledge.Results: Only 5.3% of eligible residences redeemed KI vouchers. Most surveyed residents (76.5%) were aware of living near an NPP, yet 42.5% reported doing “nothing” to plan for an emergency. Almost half of surveyed voucher users did not know when to take KI or which body part KI protects. Among voucher nonusers, 48.0% were either unaware of the program or did not remember receiving a voucher.Conclusions: Additional efforts are needed to ensure that all residents are aware of the availability of KI and that recipients of the drug understand when and why it should be taken. Minimal emergency planning among residents living near Michigan's NPPs emphasizes the need for increased emergency preparedness and awareness. Findings are particularly salient given the March 2011 Fukushima Daiichi Nuclear Power Plant emergency in Japan.(Disaster Med Public Health Preparedness. 2012;6:263–269)

scholarly journals Nuclear Power Plant Maintenance Optimization with Heuristic Algorithm

2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Andrija Volkanovski ◽  
Leon Cizelj
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Objective Function ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Risk Measure ◽  
Plant Safety ◽  
Maintenance Activities ◽  
Probabilistic Safety

The test and maintenance activities are conducted in the nuclear power plants in order to prevent or limit failures resulting from the ageing or deterioration. The components and systems are partially or fully unavailable during the maintenance activities. This is especially important for the safety systems and corresponding equipment because they are important contributors to the overall nuclear power plant safety. A novel method for optimization of the maintenance activities in the nuclear power plant considering the plant safety is developed and presented. The objective function of the optimization is the mean value of the selected risk measure. The risk measure is assessed from the minimal cut sets identified in the Probabilistic Safety Assessment. The optimal solution of the objective function is estimated with genetic algorithm. The proposed method is applied on probabilistic safety analysis model of the selected safety system of the reference nuclear power plant. Obtained results show that optimization of maintenance decreases the risk and thus improves the plant safety. The implications of the consideration of different constraints on the obtained results are investigated and presented. The future prospects for the optimization of the maintenance activities in the nuclear power plants with the presented method are discussed.

scholarly journals Application of soft computing techniques in WWER nuclear power plant safety

2019 ◽  
Vol 5 (2) ◽  
pp. 177-182
Author(s):  
Akbar Abbasi ◽  
Fahreddin Sadikoglu
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Soft Computing ◽  
Nuclear Power ◽  
Power Plants ◽  
Electricity Production ◽  
Plant Safety ◽  
Soft Computing Techniques ◽  
The World ◽  
Nuclear Power Plant Safety

Nowadays, Nuclear Power Plant (NPP) is one of the intended energy resources for the world requirement energy in future, and nuclear power plants provided 11 percent of the world’s electricity production in 2014. Meanwhile, nuclear power plant safety has always been one of the most critical issues in the world. In this paper, the nuclear power plant safety improvement using Soft Computing Techniques were analyzed. For this purpose, the support system based on Neuro-Fuzzy Diagnosis System (NFDs) method and Genetic Algorithms (GAs) approach were used. The obtained result showed that the first symptom is P3 (pressurizer pressure) and second order symptom is P2 (core coolant average temperature) in both approaches. The comparison between the NFDs method and the GAs approaches indicated that the GAs in data test results was faster than the NFDs results.

Calculation of Bounding Pressures Due to Condensation-Induced Water Hammer at the Davis-Besse Nuclear Power Plant in Response to Generic Letter 96-06

2003 ◽  
Author(s):  
G. Thomas Elicson ◽  
James P. Burelbach ◽  
Theodore A. Lang
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Water Flow ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Cooling Water ◽  
Water Hammer ◽  
Service Water ◽  
Water Columns

The U.S. NRC is currently evaluating nuclear plant responses to Generic Letter (GL) 96-06, “Assurance of Equipment Operability and Containment Integrity During Design-Basis Accident Conditions” [1]. GL 96-06 is concerned with potential two-phase flow and water hammer conditions that could be present in the cooling water systems of nuclear power plants during design-basis accidents. Nuclear power plants rely on large capacity service water pumps to supply cooling water flow, via an extensive pipe network, to heat exchangers such as room coolers, pump lube oil coolers, and containment air coolers (CACs), for normal and abnormal plant operation. Following a postulated a loss of offsite power (LOOP) event, the normal electrical power supply to the service water pump would be lost resulting in a 20 to 30 second cooling water flow interruption while a diesel generator is started and the service water pump load is sequenced onto the diesel generator. In power plants, such as the Davis-Besse Nuclear Power Plant with open service water systems that draw from a lake or a river and supply safety-related CAC heat exchangers located 30 to 40 feet above the pump outlet, this could lead to cold water column separation in the heat exchanger supply and return piping. If a loss of coolant accident (LOCA) occurs coincident with the LOOP, then boiling in the CAC heat exchanger tubes could occur, as well. Upon restoration of the cooling water flow, dynamic loading could be expected as steam condenses and water columns rejoin. The TREMOLO computer program [2,3] has been used to calculate dynamic thermal hydraulic response and reaction forces in service water piping systems for several nuclear power plants in response to GL 96-06. A consistent result obtained in each of these GL 96-06 analyses is that the LOOP + LOCA scenario produces the bounding loads rather than the LOOP-only scenario. This result seemingly contradicts current industry thinking which suggests that because the water columns are colder and the void fraction lower during LOOP-only scenarios, the LOOP-only loads should be bounding [4,5,6]. While the physics supports the conclusion that the rejoining of colder water columns will generally yield the largest water hammer pressure rise, when actual plant geometry and credible accident scenarios are analyzed, a different picture emerges. This paper couples insights obtained from the GL 96-06 TREMOLO analysis of the Davis-Besse Nuclear Power Plant with independent hand calculations and experimental evidence to support the conclusion that the LOCA+LOOP scenario will produce the bounding loads in service water piping systems.

Risk Analysis of Water Intake Structure Blockage in a Nuclear Power Plant

2017 ◽  
Author(s):  
Jinkai Wang ◽  
Feng Duan
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Risk Analysis ◽  
Nuclear Power ◽  
Power Plants ◽  
Probabilistic Method ◽  
Engineering Practice ◽  
Plant Safety ◽  
External Events ◽  
Intake Structure

With the increasing human activities and natural environment changes in the vicinity of nuclear power plants, intake structure blockage has become a major risk to challenge the nuclear power plant operation safety. This risk has been ignored for long time. There are a lot of external events that may cause intake structure blockage, such as biological events, floating objects, sand sedimentation, oil spilling, etc. The root causes to form these events are very complex and they are also very site-specific. As these external events occurrence frequencies are very difficult to be predicted due to very limited acknowledgement, current practice seldom uses detailed quantitative method to evaluate the intake structure blockage risk. This study proposed a probabilistic method in this risk analysis. The process includes external events identification and screening, plant response and quantification. A nuclear power plant was selected in this analysis as a case study. This method took a systematic process and identified some external events that were dominant contributors to the intake structure blockage. The result indicated that intake structure blockage caused by external events could be dominant risk contributors to the plant and their risk should not be ignored. Some recommendations were provided to reduce the risk. Engineering practice proves that this method is very useful to identify the plant weak points for the external events and can help to improve the plant safety.

Fuzzy multi-objective decision making approach for nuclear power plant installation

2020 ◽  
Vol 39 (5) ◽  
pp. 6339-6350
Author(s):  
Esra Çakır ◽  
Ziya Ulukan
Keyword(s):  
Linear Programming ◽  
Power Plant ◽  
Nuclear Power Plant ◽  
Energy Supply ◽  
Energy Demand ◽  
Nuclear Power ◽  
Power Plants ◽  
Total Duration ◽  
Objective Functions ◽  
Multi Objective

Due to the increase in energy demand, many countries suffer from energy poverty because of insufficient and expensive energy supply. Plans to use alternative power like nuclear power for electricity generation are being revived among developing countries. Decisions for installation of power plants need to be based on careful assessment of future energy supply and demand, economic and financial implications and requirements for technology transfer. Since the problem involves many vague parameters, a fuzzy model should be an appropriate approach for dealing with this problem. This study develops a Fuzzy Multi-Objective Linear Programming (FMOLP) model for solving the nuclear power plant installation problem in fuzzy environment. FMOLP approach is recommended for cases where the objective functions are imprecise and can only be stated within a certain threshold level. The proposed model attempts to minimize total duration time, total cost and maximize the total crash time of the installation project. By using FMOLP, the weighted additive technique can also be applied in order to transform the model into Fuzzy Multiple Weighted-Objective Linear Programming (FMWOLP) to control the objective values such that all decision makers target on each criterion can be met. The optimum solution with the achievement level for both of the models (FMOLP and FMWOLP) are compared with each other. FMWOLP results in better performance as the overall degree of satisfaction depends on the weight given to the objective functions. A numerical example demonstrates the feasibility of applying the proposed models to nuclear power plant installation problem.

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